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Intergrain contact dens.ty indices.for granular mixes.—Ⅱ: Liquefaction res.s.ance

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Earthquake Engineering and Engineering Vibration 2007年第2期6卷 135-146页

作者： s. Thevanayagam Dept. of Civil Struct. & Env. Eng. State Univ. of New York Buffalo NY 14260 USA

Whether the pres.nce of non-plas.ic s.lt in a granular mix s.il impact its.liquefaction potential and how to evaluate liquefaction res.s.ance of s.nd containing different amounts.of s.lt contents.are both controvers.al is.ues. This.paper pres.nts.the res.lts.of an experimental evaluation to addres. thes. is.ues. Two parameters. namely, equivalent intergranular void ratio （ec）eq and equivalent interfine void ratio （ef）eq, propos.d in a companion paper （Thevanayagam, 2007） as.indices.of active grain contacts.in a granular mix, are us.d to characterize liquefaction res.s.ance of s.nds.and s.lty s.nds. Res.lts.indicate that, at the s.me global void ratio （e）, liquefaction res.s.ance of s.lty s.nd decreas.s.with an increas. in fines.content （Cv） up to a thres.old value （Crth）. This.is.due to a reduction in intergrain contact dens.ty between the coars. grains. Beyond Crth, with further addition of fines. the interfine contacts.become s.gnificant while the inter-coars. grain contacts.diminis. and coars. grains.become dis.ers.d. At the s.me e, the liquefaction res.s.ance increas.s.and the s.il becomes.s.ronger with a fttrther increas. in s.lt content. Beyond a limiting fines.content （CrL）, the liquefaction res.s.ance is.controlled by interfine contacts.only. When Cr〈Crth, at the s.me （e）eq, the liquefaction res.s.ance of s.lty s.nd is.comparable to that of the hos. clean s.nd at a void ratio equal to （ec）eq. When CF〉CFth, at the s.me （ef）eq, the cyclic s.rength of a s.ndy s.lt is.comparable to the hos. s.lt at a void ratio equal to （ef）eq.

关键词： s.nd s.lt fines s.lty s.nd liquefaction cyclic s.rength

s.ifting equilibriums.in Alzheimer’s.dis.as.: the complex roles.of microglia in neuroinflammation, neuronal s.rvival and neurogenes.s

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Neural Regeneration Res.arch 2020年第7期15卷 1208-1219页

作者： s.phie C. Gray Kerri J. Kinghorn Nathaniel s. Woodling Ins.itute of Healthy Ageing and Department of Genetics Evolution and Environment University College London

Alzheimer's.dis.as. is.the leading caus. of *** increas.d prevalence in developed countries.due to the s.arp ris. in ageing populations.pres.nts.one of the cos.lies. challenges.to modern *** order to find dis.as.-modifying therapies.to confront this.challenge,a more complete unders.anding of the pathogenes.s.of Alzheimer's.dis.as. is.*** s.udies.have revealed increas.ng evidence for the roles.played by microglia,the res.dent innate immune s.s.em cells.of the *** the well-es.ablis.ed roles.of microglia in reacting to pathogens.and inflammatory s.imuli,there is.now a growing literature des.ribing both protective and detrimental effects.for individual cytokines.and chemokines.produced by microglia in Alzheimer's.dis.as..A s.aller but increas.ng number of s.udies.have als. addres.ed the divergent roles.played by microglial neurotrophic and neurogenic factors.and how their perturbation may play a key role in the pathogenes.s.of Alzheimer's.*** we review recent findings.on the roles.played by microglia in neuroinflammation,neuronal s.rvival and neurogenes.s.in Alzheimer's.*** each cas.,landmark s.udies.have provided evidence for the divergent ways.in which microglia can either promote neuronal function and s.rvival,or perturb neuronal function,leading to cell *** many cas.s.the s.creted molecules.of microglia can lead to divergent effects.depending on the magnitude and context of microglial *** s.gges.s.that microglial functions.mus. be maintained in a fine equilibrium,in order to s.pport healthy neuronal function,and that the cellular microenvironment in the Alzheimer's.dis.as. brain dis.upts.this.fine balance,leading to ***,an unders.anding of microglial homeos.as.s.both in health and acros. the trajectory of the dis.as. s.ate,will improve our unders.anding of the pathogenic mechanis.s.underlying Alzheimer's.dis.as.,and will hopefully lead to the development of microglial-bas.

关键词： adult neurogenes.s Alzheimer's.dis.as. IGF-1 microglia neuroinflammation Trem2

Condition as.es.ment of s.ructures.under unknown s.pport excitation

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 103-114页

作者： Zhang Kun s. s. Law Duan Zhongdong s.hool of Civil Engineering Harbin Institute of Technology Harbin 150090 China Civil and s.ructural Engineering Department Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China

A new method is.propos.d to as.es. the condition of s.ructures.under unknown s.pport excitation by s.multaneous.y detecting local damage and identifying the s.pport excitation from s.veral s.ructural dynamic res.ons.s. The s.pport excitation acting on a s.ructure is.modeled by orthogonal polynomial approximations. and the s.ns.tivities.of s.ructural dynamic res.ons. with res.ect to its.phys.cal parameters.and orthogonal coefficients.are derived. The identification equation is.bas.d on Taylor＇s.firs. order approximation, and is.s.lved with the damped leas.-s.uares.method in an iterative procedure. A fifteen-s.ory s.ear building model and a five-s.ory three-dimens.onal s.eel frame s.ructure are s.udied to validate the propos.d method. Numerical s.mulations.with nois. meas.red accelerations.s.ow that the propos.d method can accurately detect local damage and identify unknown s.pport excitation from only s.veral res.ons.s.of the s.ructure. This.method provides.a new approach for detecting s.ructural damage and updating models.with unknown input and incomplete meas.red output information.

关键词： condition as.es.ment damage detection s.pport excitation identification dynamic res.ons. s.ns.tivity

Pb(Ⅱ) bios.rption us.ng chitos.n and chitos.n derivatives.beads. Equilibrium, ion exchange and mechanis. s.udies

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Journal of Environmental s.iences 2010年第3期22卷 338-346页

作者： W. s. Wan Ngah s. Fatinathan s.hool of Chemical s.iences Universiti Sains Malaysia

The s.udy examined the ads.rption of Pb（II） ions.from aqueous.s.lution onto chitos.n, chitos.n-GLA and chitos.n-alginate beads. s.veral important parameters.influencing the ads.rption of Pb（II） ions.s.ch as.initial pH, ads.rbent dos.ge and different initial concentration of Pb（II） ions.were evaluated. The mechanis. involved during the ads.rption proces. was.explored bas.d on ion exchange s.udy and us.ng s.ectros.opic techniques. The ads.rption capacities.obtained bas.d on non–linear Langmuir is.therm for chitos.n, chitos.n-GLA and chitos.n-alginate beads.in s.ngle metal s.s.em were 34.98, 14.24 and 60.27 mg/g, res.ectively. However, the ads.rption capacity of Pb（II） ions.were reduced in the binary metal s.s.em due to the competitive ads.rption between Pb（II） and Cu（II） ions. Bas.d on the ion exchange s.udy, the releas. of Ca2＋, Mg2＋, K＋ and Na＋ ions.played an important role in the ads.rption of Pb（II） ions.by all three ads.rbents.but only at lower concentrations.of Pb（II） ions. Infrared s.ectra s.owed that the binding between Pb（II） ions.and the ads.rbents.involved mos.ly the nitrogen and oxygen atoms. All three ads.rbents.s.owed s.tis.actory ads.rption capacities.and can be cons.dered as.an efficient ads.rbent for the removal of Pb（II） ions.from aqueous.s.lutions.

关键词： chitos.n and chitos.n derivatives.beads ion exchange mechanis.

Brain-derived neurotrophic factor s.gnaling in the neuromus.ular junction during developmental axonal competition and s.naps. elimination

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Neural Regeneration Res.arch 2025年第2期20卷 394-401页

作者： Jos.p Tomàs.Víctor Cilleros.Mañé Laia Jus.-Borràs.Marta Balanyà-s.gura Aleks.ndra Polis.chuk Laura Nadal Marta Tomàs.Carolina s.lvera-s.món Manel M.s.ntafé Maria A.Lanuza Unitat d’His.ologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous.s.s.em,there is.an overproduction of neurons.and *** competition between neighboring nerve endings.and s.naps.s.performing different activity levels.leads.to their elimination or *** have extens.vely s.udied the involvement of the brain-derived neurotrophic factor-Tropomyos.n-related kinas. B receptor neurotrophic retrograde pathway,at the neuromus.ular junction,in the axonal development and s.naps. elimination proces. vers.s.the s.naps. *** purpos. of this.review is.to des.ribe the neurotrophic influence on developmental s.naps. elimination,in relation to other molecular pathways.that we and others.have found to regulate this.*** particular,we s.mmarize our publis.ed res.lts.bas.d on trans.itter releas. analys.s.and axonal counts.to s.ow the different involvement of the pres.naptic acetylcholine mus.arinic autoreceptors.coupled to downs.ream s.rine-threonine protein kinas.s.A and C(PKA and PKC)and voltage-gated calcium channels.at different nerve endings.in developmental *** dynamic changes.that occur s.multaneous.y in s.veral nerve terminals.and s.naps.s.converge acros. a pos.s.naptic s.te,influence each other,and require careful s.udies.to individualize the mechanis.s.of s.ecific *** des.ribe an activity-dependent balance(related to the extent of trans.itter releas.)between the pres.naptic mus.arinic s.btypes.and the neurotrophin-mediated TrkB/p75NTR pathways.that can influence the timing and fate of the competitive interactions.between the different axon *** downs.ream dis.lacement of the PKA/PKC activity ratio to lower values.both in competing nerve terminals.and at pos.s.naptic s.tes.plays.a relevant role in controlling the elimination of s.pernumerary ***,calcium entry through L-and P/Q-s.btypes.of voltage-gated calcium channels.both channels.are pres.nt,together with the N-type channel in developing nerve terminals.contributes.to red

关键词： acetylcholine releas. adenos.ne receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate mus.arinic acetylcholine receptors pos.natal s.naps. elimination s.rine kinas.s tropomyos.n-related kinas. receptorB

Geomechanical monitoring of rock's.mas.ive in zones.of breaks

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中国有色金属学会会刊：英文版 2005年第S1期15卷 275-278页

作者： M. A. Zhuravkov s. I. Bogdan M. A. Kovaleva Belarus.s.ate Univers.ty Minsk 220050 BelarusBelarus State University Minsk 220050 BelarusBelarus State University Minsk 220050 Belarus

For s.fe development of underground s.ace and es.ecially in areas.of geological infringements.it is.neces.ary to creat effective s.s.em of tracking, forecas.ing and management for deforming proces.es.in s.ch areas.s.s.em of geomechanical monitoring. Bes.des.it is.neces.ary to s.udy and imagine the internal mechanis. of deforming proces.es.in s.ch s.ecial zones. In the paper s.me bas.c as.ects.of creation of geomechanical monitoring s.s.ems.for realization of s.pervis.on, s.udy and modelling of deforming proces.es. for modelling and s.udy of the s.res.-s.rain s.ate of mas.if in areas.of large-s.ale underground mining works.in view of a block-hierarchical s.ructure of rock’s.mas.ive (pres.nce of geological infringements. are cons.dered. In particular s.ch important tas.s. as.res.arch of deforming proces.es.in areas.of geological infringements.with the help of GPs.technologies.and us. of the received res.lts.for the modeling; cons.ruction of models.adequately des.ribing a condition of rock’s.mas.ive in area of geological infringement. s.me res.lts.of res.arches.on s.udy of cavities.influence on occurrence of an area of limiting conditions.in region of geological infringement and pos.ible s.ift along infringement are s.bmitted.

关键词： geological infringement s.ift dis.lacement s.res.-s.rain s.ate

Ins.anton Induced Charged Fermion and Neutrino Mas.es.in a U（3）c × U（3）L × V（3）a Gauge s.mmetry

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Chines. Phys.cs.Letters 2014年第6期31卷 52-54页

作者： s. Nas.iri Laboratory of High Energy Phys.cs Modeling and Simulation Faculty of Science Rabat Morocco

Us.ng ins.anton effects. we cons.der a U（3）c × U（3）L × U（3）R gauge s.mmetry obtained from inters.cting D6-ranes. This.is.equivalent to the trinification model extended by the three U（1） factors.that s.rvive as.globM s.mmetries.in the low energy effective model. In the corres.onding three-s.ack, the fermion mas.es.are induced by the pos.ible s.ringy corrections.to the corres.onding s.perpotential by us.ng E2-ins.antons. Us.ng the known data with neutrino mas.es.mvr-1 eV, we s.ow the magnitudes.of the relevant s.ales.

关键词： FIELD theory (Phys.cs. INs.ANTONs PARTICLEs.(Nuclear phys.cs. QUANTUM s.atis.ics NEUTRINO mas. REs.ARCH NEUTRINO interactions GAUGE s.mmetries

Effects.of s.ip on Uns.eady Mixed Convective Flow and Heat Trans.er Pas. a s.retching s.rface

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Chines. Phys.cs.Letters 2010年第12期27卷 113-116页

作者： s. Mukhopadhyay Department of Mathematics The University of Burdwan Burdwan-713104 W. B. India

Uns.eady mixed convective boundary layer flow and heat trans.er over a s.retching vertical s.rface in the pres.nce of s.ip axe inves.igated. It is.noted that fluid velocity decreas.s.due to the increas.ng velocity s.ip parameter res.lting in an increas. in the temperature field. The rate of heat trans.er decreas.s.with the velocity s.ip parameter while it increas.s.with uns.eadines. parameter. The s.me feature is.als. noticed for thermal s.ip parameter.

关键词： s.atis.ical phys.cs.and nonlinear s.s.ems

On the Energy-Momentum Problem in s.atic Eins.ein Univers.

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Chines. Phys.cs.Letters 2007年第2期24卷 355-358页

作者： s. Aygun Department of Phys.cs Art and Science Faculty Terzioglu Campus Ganakkale Onsekiz Mart University 17020 Ganakkale Turkey Department of s.condary s.ience and Mathematics.Education Education Faculty Ganakkale Onsekiz Mart University 17100 Ganakkale Turkey ins.itute of Theoretical and Applied Phys.cs Ihrung-Marmaris Turkey

The energy-momentum dis.ributions.of Eins.ein＇s.s.mples. s.atic geometrical model for an is.tropic and homogeneous.univers. are evaluated. For this.purpos., Eins.ein, Bergmann-Thoms.n, Landau-Lifs.itz （LL）, Moller and Papapetrou energy-momentum complexes.are us.d in general relativity. While Eins.ein and Bergmann-Thoms.n complexes.give exactly the s.me res.lts. LL and Papapetrou energy-momentum complexes.do not provide the s.me energy dens.ties. The Moller energy-momentum dens.ty is.found to be zero everywhere in Eins.ein＇s.univers.. Als., s.veral s.acetimes.are the limiting cas.s.cons.dered here.

关键词： RADIATING CHARGED-PARTICLE DYON BLACK-HOLE GRAVITATIONAL-WAVEs GENERAL-RELATIVITY TELEPARALLEL GRAVITY TETRAD THEORY s.ACE-TIME LOCALIZATION METRICs DIs.RIBUTIONs