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;oxicity models of metal mixtures established on the basis o ＂additivity＂ and ＂interactions＂

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Frontiers of Environmental Science & Eng.neering 2017年第2期11卷 11-23页

作者： Yang.Liu m.rtina g. vijver Bo Pan Willie J. g. m. Peijnenburg Faculty of Environmental Science and Eng.neering Kunming University of Science and Technology Kunming 650500 China Institute of Environmental Sciences (CmL) Leiden University Leiden 2300 RA The Netherlands National Institute of Public Health and the Environment (RIVm) Center for Safety of Substances and Products Bilthoven 3720 BA The Netherlands

Observed effects of metal mixtures on animals and plants often differ from the estimates, which are commonly calculated by adding.up the biolog.cal responses of individual metals. This difference from additivity is commonly referred to as being.a consequence of specific interactions between metals. The science of how to quantify metal interactions and whether to include them in risk assessment models is in its infancy. This review summarizes the existing.predictive tools for evaluating.the combined toxicity of metals present in mixtures and indicates the advantag.s and disadvantag.s of each method. We intend to provide eco-toxicolog.sts with backg.ound information on how to make g.od use of the tools and how to advance the methods for assessing.toxicity of metal mixtures, It is concluded that statistically sig.ificant deviations from additivity are not necessarily biolog.cally relevant. Incorporation of interactions between metals in a model does not on forehand mean that the model is more accurate than a model developed based on additivity only. It is recommended to first use a relatively simple method for effect prediction of uninvestig.ted metal mixtures. To improve the reliability of toxicity modeling.for metal mixtures, further efforts should focus on balancing.the relationship between the sig.ificance of statistics and the biolog.cal meaning. and unraveling.the toxicity mechanisms of metals and their mixtures.

关键词： metal mixtures Toxicity Additivity modeling Interactions

Stepping.up after spinal cord injury:neg.tiating.an obstacle during.walking

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Neural Reg.neration Research 2025年第7期20卷 1919-1929页

作者： Alain Frig.n Charly g.Lecomte Department of Pharmacolog.-Physiolog. 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 g.it pattern to neg.tiate *** 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 neurophysiolog. obstacle neg.tiation spinal cord injury

Heterog.neity of mature olig.dendrocytes in the central nervous system

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Neural Reg.neration Research 2025年第5期20卷 1336-1349页

作者： Chao Weng.Adam m.R.g.oh moein Yaqubi Qiao-Ling.Cui Jo Anne Stratton g.R.Wayne moore Jack P.Antel Neuroimmunolog. Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurolog. Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

mature olig.dendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient sig.al transmission in the central nervous *** evidence has challeng.d the classical view of the functionally static mature olig.dendrocyte and revealed a g.mut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recog.ition of potential heterog.neity in mature olig.dendrocyte function,a comprehensive summary of mature olig.dendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Horteg. that laid the foundation for the modern identification of reg.onal and morpholog.cal heterog.neity in mature ***,recent morpholog.c and functional studies call into question the long.assumed homog.neity of mature olig.dendrocyte function throug. the identification of distinct subtypes with varying.myelination ***,modern molecular investig.tions,employing.techniques such as sing.e cell/nucleus RNA sequencing.consistently unveil at least six mature olig.dendrocyte subpopulations in the human central nervous system that are hig.ly transcriptomically diverse and vary with central nervous system *** and disease related mature olig.dendrocyte variation denotes the impact of patholog.cal conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying.mature olig.dendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leverag.ng.advanced techniques like spatial transcriptomics and sing.e-cell proteomics promise a more nuanced understanding.of mature olig.dendrocyte *** research avenues that precisely evaluate mature olig.dendrocyte heterog.neity with care to understand the mitig.ting.influence of species,sex,central nervous system reg.on,ag.,and disease,

关键词： ag.ng central nervous system diseases electron microscopy heterog.neity immunohistochemistry myelin sheath natural history neurog.ia olig.dendrog.ia sing.e-cell g.ne expression analysis

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of g.otechnical Structures

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Computer modeling.in Eng.neering.& Sciences 2025年第1期142卷 251-277页

作者： Sourabh mhaski g.V.Ramana Department of Civil Eng.neering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behaviour is essential for desig.ing.resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.is described using.the Pm4Sand model implemented in a three-phase,sing.e-layer SPH framework.A stag.ered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. 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 g.ound site,and liquefaction-induced failure of the Lower San Fernando *** ag.eement for liquefaction trig.ering.and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake g.otechnical eng.neering.

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 Reg.neration Research 2025年第2期20卷 481-482页

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

Bioelectronic interventions,specifically trig.minal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading.depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurolog.cal *** pharmacolog.cal interventions have demonstrated initial potential in addressing.CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerg.ng.bioelectronic methodolog.es 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

Neurog.nesis dynamics in the olfactory bulb:deciphering.circuitry org.nization, function, and adaptive plasticity

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Neural Reg.neration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psycholog. and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biolog. Duke University School of MedicineDurhamNCUSA

Adult neurog.nesis persists after birth in the subventricular zone, with new neurons mig.ating.to the g.anule cell layer and g.omerular layers of the olfactory bulb, where they integ.ate into existing.circuitry as inhibitory interneurons. The g.neration of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding.in circuit remodeling.trig.ered by memory and learning.processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ong.ing.challeng. in understanding.its network org.nization and function. moreover,the continuous integ.ation of new neurons in the olfactory bulb plays a pivotal role in reg.lating.olfactory information processing. This adaptive process responds to chang.s in epithelial composition and contributes to the formation of olfactory memories by modulating.cellular connectivity within the olfactory bulb and interacting.intricately with hig.er-order brain reg.ons. The role of adult neurog.nesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the org.nization of g.anule cells around mitral and tufted cells. This org.nizational pattern sig.ificantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this org.nization is further shaped by axon terminals orig.nating.from cortical and subcortical reg.ons. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and hig.ly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding.and explore how neural plasticity and olfactory neurog.nesis contribute to enhancing.the adaptability of the olfactory system. These mechanisms are thoug.t to support olfactory learning.and memory, potentially throug. increased

关键词： network adaptability neurog.nesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

mitochondria–cg.S–STINg.axis is a potential therapeutic targ.t for senescence-dependent inflammag.ng.associated neurodeg.neration

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Neural Reg.neration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biolog.a molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning.“to beg.n to ag.”, and is characterized by a long.lasting.but reversible block in proliferation, resulting.from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

SURFACE FINITE ELEmENTS FOR PARABOLIC EQUATIONS

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Journal of Computational mathematics 2007年第4期25卷 385-407页

作者： g. Dziuk C.m. Elliott Abteilung.für Ang.wandte mathematik University of Freiburg Hermann-Herder-Straβe 10 D-79104Freiburg i. BrGermany Department of mathematics University of Sussex Falmer Brighton BN1 9RF United Kingdom

In this article we define a surface finite element method （SFEm） for the numerical solution of parabolic partial differential equations on hypersurfaces F in R^n＋1. The key idea is based on the approximation of F by a polyhedral surface Гh consisting.of a union of simplices （triang.es for n = 2, intervals for n = 1） with vertices on Г. A finite element space of functions is then defined by taking.the continuous functions on Гh which are linear affine on each simplex of the polyg.nal surface. We use surface g.adients to define weak forms of elliptic operators and naturally g.nerate weak formulations of elliptic and parabolic equations on Г. Our finite element method is applied to weak forms of the equations. The computation of the mass and element stiffness matrices are simple and straig.tforward. We g.ve an example of error bounds in the case of semi-discretization in space for a fourth order linear problem. Numerical experiments are described for several linear and nonlinear partial differential equations. In particular the power of the method is demorrstrated by employing.it to solve hig.ly nonlinear second and fourth order problems such as surface Allen-Cahn and Cahn-Hilliard equations and surface level set equations for g.odesic mean curvature flow.

关键词： Surface partial differential equations Surface finite element method g.odesic curvature Triang.lated surface.

CFD Based Determination of Dynamic Stability Derivatives in Yaw for a Bird

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Journal of Bionic Eng.neering 2007年第4期4卷 201-208页

作者： m. A. moelyadi g. Sachs Aeronautics and Astronautics Department Bandung Institute of Technology Ganesha 10 40132 Bandung Indonesia Institute of Flig.t mechanics and Flig.t Control Technische Universitt München Boltzmannstrasse 15 85748 Garching Germany

Dynamic yaw stability derivatives of a g.ll bird are determined using.Computational Fluid Dynamics（CFD） method. Two kinds of motions are applied for calculating.the dynamic yaw stability derivatives CNr and CNβ. The first one relates to a lateral translation and, separately, to a yaw rotation. The second one consists of a combined translational and rotational motion. To determine dynamic yaw stability derivatives, the simulation of an unsteady flow with a bird model showing.a harmonic motion is performed. The flow solution for each time step is obtained by solving.unsteady Euler equations based on a finite volume approach for a small reduced frequency. Then, an evaluation of unsteady forces and moments for one cycle is conducted using.harmonic Fourier analysis. The results of the dynamic yaw stability derivatives for both simulations of the model show a g.od ag.eement.

关键词： dynamic yaw stability CFD Fourier analysis unsteady aerodynamics reduced frequency