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Brain-derived neurotrophic factor signaling in the neurom.scular junction during developm.ntal axonal com.etition and synapse elim.nation

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neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tom.s Víctor Cilleros-m.ñé Laia Just-Borràs m.rta Balanyà-Segura Aleksandra Polishchuk Laura nadal m.rta Tom.s Carolina Silvera-Sim.n m.nel m.Santafé m.ria A.Lanuza Unitat d’Histologia i neurobiologia(UHneurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the developm.nt of the nervous system.there is an overproduction of neurons and *** com.etition between neighboring nerve endings and synapses perform.ng different activity levels leads to their elim.nation or *** have extensively studied the involvem.nt of the brain-derived neurotrophic factor-Tropom.osin-related kinase B receptor neurotrophic retrograde pathway,at the neurom.scular junction,in the axonal developm.nt and synapse elim.nation process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developm.ntal synapse elim.nation,in relation to other m.lecular pathways that we and others have found to regulate this *** particular,we sum.arize our published results based on transm.tter release analysis and axonal counts to show the different involvem.nt of the presynaptic acetylcholine m.scarinic autoreceptors,coupled to downstream.serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium.channels,at different nerve endings in developm.ntal *** dynam.c changes that occur sim.ltaneously in several nerve term.nals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the m.chanism. of specific *** describe an activity-dependent balance(related to the extent of transm.tter release)between the presynaptic m.scarinic subtypes and the neurotrophin-m.diated TrkB/p75nTR pathways that can influence the tim.ng and fate of the com.etitive interactions between the different axon *** downstream.displacem.nt of the PKA/PKC activity ratio to lower values,both in com.eting nerve term.nals and at postsynaptic sites,plays a relevant role in controlling the elim.nation of supernum.rary ***,calcium.entry through L-and P/Q-subtypes of voltage-gated calcium.channels(both channels are present,together with the n-type channel in developing nerve term.nals)contributes to red

关键词： acetylcholine release adenosine receptors axonal com.etition brain-derived neurotrophic factor calcium.channels m.tor end-plate m.scarinic acetylcholine receptors postnatal synapse elim.nation serine kinases tropom.osin-related kinase receptorB

Particle m.xing rates using the two-fluid m.del

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Particuology 2018年第1期16卷 13-26页

作者： m. Banaei n.G. Deen m. van Sint Annaland J.A.m. Kuipers m.ltiphase Reactors Group Deportment of Chemical Engineering & Chemistry Eindhoven University of Technology 5600 MB Eindhoven The Netherlands Dutch Polym.r Institute (DPI) 5600 AX Eindhoven The Netherlands m.ltiphase and Reactive Flows Group Department of Mechanical Engineering Eindhoven University of Technology 5600 MB Eindhoven The Netherlands

In this work, a new m.thodology is introduced to calculate the solids m.xing rate in dense gas-fluidized beds using the two-fluid m.del. The im.lem.ntation of this m.thodology into an existing two-fluid m.del code was carefully verified. The solids phase continuity equation was satisfied using our m.thod, and the sensitivity of the com.utational results to the tim. step, com.utational cell size, and discretization schem. was investigated to determ.ne the optim.l sim.lation settings. Using these sim.lation settings, the degree of solids m.xing was observed to rapidly （exponentially） increase with increasing operating pressure and linearly decrease with increasing bed diam.ter. Our novel m.thodology can be applied to analyze m.xing processes in large lab-scale beds as an alternative to existing tim.-consum.ng sim.lation techniques such as com.utational fluid dynam.cs com.ined with the discrete elem.nt m.del.

关键词： Gas-solid fluidized bed Sim.lation Two-fluid m.del Solids m.xing Pressure Scale up

Catalytic activity of m.nganese oxide supported on alum.na in the synthesis of quinoxalines

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Frontiers of Chem.cal Science and Engineering 2013年第4期7卷 415-421页

作者： Rekha m. Kathyayini H nagaraju n Catalysis Research Laboratory St Joseph's College Post Graduate and Research Centre Bangalore 560027 India Centre for Em.rging Technologies Global Campus Jain University Bangalore 562112 India

Two catalysts, alum.na and m.nganese oxide supported on alum.na, have been prepared by calcination and precipitation-im.regnation m.thods, respectively. The catalysts are characterised by the following techniques： Brunner-Em.ett-Teller-n2 adsorption-desorption for sur- face area, tem.erature program.ed desorption of nH3 and n-butyl am.ne back titration m.thods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform.infrared spectroscopy for the anionic radicals. The catalytic activity has been determ.ned under heterogeneous conditions in the condensation reaction between o-phenylenediam.ne and benzil. The product purity is checked by thin-layer chrom.tography and m.lting point. The products are also analysed by LC-m. and 1H-nm. techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction para- m.ters such as tem.erature, reaction tim., am.unt of the catalyst, nature of solvent and m.lar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an im.ortant role in activating the reaction.

关键词： alum.na m.nganese oxide deposited onalum.na quinoxaline synthesis

Investigating the effect of entrance channel m.ss asym.etry on fusion reactions using the Skyrm. energy density form.lism

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nuclear Science and Techniques 2020年第9期31卷 45-52页

作者： m.m.Hosam.ni A.Vinayak n.m.Badiger Departm.nt of Studies in Physics Karnatak UniversityDharwad 580003India

In the present investigations,the fusion crosssections for the form.tion of 200Pb com.ound nucleus(Cn)using 16O+184 W,30Si+170Er,and 40Ar+160Gd nuclear reactions at energies above the Coulom. barrier were calculated to understand the effect of entrance channel m.ss asym.etry(α)on the fusion reactions;the Skyrm. energy density form.lism.SEDF)was used for this *** SEDF uses the Hartree-Fock-Bogolyubov(HFB)com.utational program.with Skyrm. forces such as Skm.,SLy4,and SLy5 to obtain the nucleus-nucleus potential param.ters for the above *** the SEDF m.del with Skm.,SLy4,and SLy5 interaction forces,the theoretical fusion cross-sections were determ.ned above the barrier energy and com.ared with the available experim.ntal fusion *** results show a close agreem.nt between the theoretical and experim.ntal values for all selected system. at energies well above the ***,near the barrier energies,the theoretical values were observed to be higher than the experim.ntal values.

关键词： Skyrm. force Energy density form.lism Hartree-Fock-Bogolyubov Thom.s-Ferm. m.del Coupled-channel calculation

DSC study on tem.erature m.m.ry effect of niTi shape m.m.ry alloy

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中国有色金属学会会刊：英文版 2006年第B01期16卷 37-41页

作者： n. LIU W. m. HUAnG School of m.chanical and Aerospace Engineering Nanyang Technological University Singapore 639798

A system.tic study on the tem.erature m.m.ry effect (Tm.) in a polycrystalline niTi shape m.m.ry alloy was presented. The investigation was carried out through a series of differential scanning calorim.ter (DSC) tests. Two types of tests were conducted, nam.ly single-step test and m.lti-step test. The influence of the step tem.erature on the peak/trough tem.eratures in the subsequent heating process and the associated energy absorption/release in the phase transform.tions was investigated. Using a sim.le theoretical m.del, the exact m.chanism.behind Tm. was studied.

关键词：镍钛合金形状记忆合金温度记忆效应相转变差分扫描量热计

m.bility of Arsenic and Heavy m.tals in a Sandy-Loam.Textured and Carbonated Soil

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Pedosphere 2009年第2期19卷 166-175页

作者： I. GARC íA m. DIEZ F. m.RT ín m. SIm.n C. DORROnSORO Departam.nto Edafologia y Quim.ca Agricola CITE IIB Carretera Sacramento s/n 04120 University of Almeria (Spain) Departam.nto Edafologia y Quim.ca Agricola Campus Fuentenueva s/n 18002 University of Granada (Spain)

The continued effect of the pyrite-tailing oxidation on the m.bility of arsenic, lead, zinc, cadm.um. and copper was studied in a carbonated soil under natural conditions, with the experim.ntal plot preserved with a layer of tailing covering the soil during three years. The experim.ntal area is located in Southern Spain and was affected by a pyrite-m.ne spill. The clim.te in the area is typically m.diterranean, which determ.nes the rate of soil alteration and elem.nt m.bility. The intense alteration processes that occurred in the soil during three years caused im.ortant changes in its m.rphology and a strong degradation of the m.in soil properties. In this period, lead concentrated in the first 5 m. of the soil, with concentrations higher than 1500 m. kg?1, m.inly associated to the neoform.tion of plum.ojarosite. Arsenic was partially leached from.the first 5 m. and m.inly concentrated between 5–10 m. in the soil, with m.xim.m.values of 1239 m. kg-1; the retention of arsenates was related to the neoform.tion of iron hydroxysulfates (jarosite, schwertm.nnite) and oxyhydroxides (goethite, ferrihydrite), both with a variable degree of crystallinity. The m.bility of Zn, Cd, and Cu was highly affected by pH, producing a stronger leaching in depth; their retention was related to the form. of precipitated alum.nium.and, in the case of Cu, also to the neoform.tion of hydroxysulfate.

关键词： arsenic heavy m.tals oxidation pyrite-tailing soil

Dynam.c analysis of a fractional order system

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International Journal of Biom.them.tics 2015年第6期8卷 157-173页

作者： m. Javidi n. nyam.radi Faculty of m.them.tical SciencesUniversity of Tabriz Tabriz Iran Departm.nt of m.them.tics Faculty of Sciences Razi University 67149 Kermanshah Iran

In this paper, we investigate the dynam.cal behavior of a fractional order phytoplankton- zooplankton system. In this paper, stability analysis of the phytoplankton zooplankton m.del （PZm. is studied by using the fractional Routh-Hurwitz stability conditions. We have studied the local stability of the equilibrium.points of PZm. We applied an efficient num.rical m.thod based on converting the fractional derivative to integer derivative to solve the PZm.

关键词： Phytoplankton-zooplankton m.del Routh-Hurwitz stability conditions num.rical sim.lation.

A fractional-order toxin producing phytoplankton and zooplankton system

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International Journal of Biom.them.tics 2014年第4期7卷 63-83页

作者： m. Javidi n. nyam.radi Faculty of m.them.tical SciencesUniversity of Tabriz Tabriz Iran Departm.nt of m.them.ticsFaculty of Sciences Razi University 67149 Kermanshah Iran

In this work, we investigate the dynam.cal behavior of a fractional-order toxin producing on a phytoplankton-zooplankton （TPPZ） system.with nutrient cycling. We propose a m.them.tical system.to m.del this situation. All the feasible equilibria of the system.are obtained and the conditions for the existence of the equilibrium. are determ.ned. Local stability analysis of the TPPZ is studied by using the fractional Routh-Hurwitz stability conditions. num.rical sim.lations are carried out for a hypothetical set of param.ter values to substantiate our analytical findings.

关键词： Toxic-phytoplankton zooplankton stability num.rical sim.lation frac-tional-order.

m.chanical properties of steel, glass, and hybrid fiber reinforced reactive powder concrete

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Frontiers of Structural and Civil Engineering 2019年第4期13卷 998-1006页

作者： Atheer H. m. ALGBURI m. neaz SHEIKH m.ham.ad n. S. HADI School of Civil Mining and Environmental Engineering University of Wollongong NSW 2522 Australia

This study exam.nes the properties of fiber-reinforced reactive powder concrete (FR-RPC). Steel fibers, glass fibers, and steel-glass hybrid fibers were used to prepare the FR-RPC. The non-fibrous reactive powder concrete (nF-RPC) was prepared as a reference m.x. The proportion of fibers by volum. for all FR-RPC m.xes was 1.5%. Steel fibers of 13 m. length and 0.2 m. diam.ter were used to prepare the steel fiber-reinforced RPC (SFR-RPC). Glass fibers of 13 m. length and 1.3 m. diam.ter were used to prepare the glass fiber-reinforced RPC (GFR-RPC). The hybrid fiber-reinforced RPC (HFR-RPC) was prepared by m.xing 0.9% steel fibers and 0.6% glass fibers. Com.ressive strength, axial load-axial deform.tion behavior, m.dulus of elasticity, indirect tensile strength, and shear strength of the RPC m.xes were investigated. The results showed that SFR-RPC achieved higher com.ressive strength, indirect tensile strength and shear strength than nF-RPC, GFR-RPC, and HFR-RPC. Although the com.ressive strengths of GFR-RPC and HFR-RPC were slightly lower than the com.ressive strength of nF-RPC, the shear strengths of GFR-RPC and HFR-RPC were higher than that of nF-RPC.

关键词： reactive powder concrete steel fiber glass fiber hybrid fiber