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温度对氨基苯甲酸在粗糙银表面上行为的影响

光谱学与光谱分析 2000年第3期20卷 315-317页

作者：瞿金蓉 pmfredericks 湖北工学院化工系武汉430068 CenterforInstrumentalandDevelopmentalChemistry QueenslandUniversityofTechnologyQLD4001Australia

本文同时测定了当温度从 - 190℃上升到 30℃和从 30℃下降到 - 190℃对氨基苯甲酸 (p -Aminobenzoic Acid,pABA)和邻氨基苯甲酸 (o- Aminobenzoic Acid,OABA)在粗糙的银表面上的表面增强拉曼光谱的变化。结果表明 ,若吸附质表面拉曼光... 详细信息

本文同时测定了当温度从 - 190℃上升到 30℃和从 30℃下降到 - 190℃对氨基苯甲酸 (p -Aminobenzoic Acid,pABA)和邻氨基苯甲酸 (o- Aminobenzoic Acid,OABA)在粗糙的银表面上的表面增强拉曼光谱的变化。结果表明 ,若吸附质表面拉曼光谱的增强主要表现为化学机理 ,且整个分子平躺在表面 ,则分子在表面上的取向不会随温度的变化而改变。而温度的变化会引起基于电磁场增强机理的振动频率移动。

关键词：表面增强拉曼散射氨基苯甲酸温度取向银表面

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural Regeneration Research 2025年第5期20卷 1336-1349页

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

mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Samuel E.Ocasio Rivera Dina p.Bracho-Rincon Luis H.pagan Rivera Jorge D.miranda Department of physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

几种水溶性porphyrin在电化学处理的银表面上的表面增强拉曼光谱(英文)

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华中师范大学学报（自然科学版） 2000年第1期34卷 70-73页

作者：瞿金蓉朱传方王贤明 fredericks p m 湖北工学院化工系武汉430068 华中师范大学化学系武汉430079 Center for Instrumental and Developmental Chemistry Queensland University of Technology

利用波长为632．8nm激光激发的拉曼光谱仪，测定了三种水溶性porphyrin在电化学粗糙银表面上的表面增强拉曼光谱（SERS）．这些光谱非常相似，但也有一些重要的差别．实验还表明：当Sn（Ⅳ）Tmpyp（4）吸附在Ag表面上时，Sn-N键仍稳定... 详细信息

利用波长为632．8nm激光激发的拉曼光谱仪，测定了三种水溶性porphyrin在电化学粗糙银表面上的表面增强拉曼光谱（SERS）．这些光谱非常相似，但也有一些重要的差别．实验还表明：当Sn（Ⅳ）Tmpyp（4）吸附在Ag表面上时，Sn-N键仍稳定存在，而且吸附分子的表面浓度不同，其在表面的取向也不同．

关键词：表面增强拉曼散射电化学处理 porphyrin 银表面

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

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Neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto Doncel-pérez Gabriel Guízar-Sahagún Israel Grijalva-Otero Hospital Nacional de parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain medical Research Unit for Neurological Diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Surface plasmon oscillations in a semi-bounded semiconductor plasma

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plasma Science and Technology 2018年第2期20卷 76-81页

作者： m SHAHmANSOURI A p mISRA Department of physics Faculty of ScienceArak University Department of mathematics Siksha BhavanaVisva-Bharati University

We study the dispersion properties of surface plasmon（Sp） oscillations in a semi-bounded semiconductor plasma with the effects of the Coulomb exchange（CE） force associated with the spin polarization of electrons and holes as well as the effects of the Fermi degenerate pressure and the quantum Bohm *** from a quantum hydrodynamic model coupled to the poisson equation,we derive the general dispersion relation for surface plasma *** results in this context are *** dispersion properties of the surface waves are analyzed in some particular cases of interest and the relative influence of the quantum forces on these waves are also studied for a nano-sized Ga As semiconductor *** is found that the CE effects significantly modify the behaviors of the Sp *** present results are applicable to understand the propagation characteristics of surface waves in solid density plasmas.

关键词： surface plasmon oscillations semiconductor plasma semi-bounded plasma

Hunting down the ohmic contact of organic field-effect transistor

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Chinese physics B 2019年第11期28卷 382-387页

作者： m micjan m Novota p Telek m Donoval m Weis Institute of Electronics and photonics Slovak University of Technology

We report properties of contact resistances observed on pentacene organic field-effect transistors(OFET) with four different source/drain electrodes, namely, copper(Cu), gold(Au), silver(Ag), and germanium(Ge). The metals were selected to provide a wide range of energy barriers for charge injection, from blocking contact to smooth injection. All OFETs exhibited strong voltage dependence of the contact resistance, even for devices with smooth injection, which is in strong disagreement with the definition of ohmic contacts. A comparison with current crowding, resistive network, Fowler–Nordheim tunneling, and electric field enhanced thermionic injection(Schottky emission) pointed to importance of local electric fields and/or electrostatic field charges.

关键词： organic field-effect transistors contact resistance charge injection

Non-Newtonian effect on natural convection flow over cylinder of elliptic cross section

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Applied mathematics and mechanics(English Edition) 2020年第2期41卷 361-382页

作者： p.NAG m.m.mOLLA m.A.HOSSAIN Department of mathematics and physics North South UniversityDhaka 1229Bangladesh Center for Applied Scientific Computing(CASC) North South UniversityDhaka 1229Bangladesh Department of mathematics University of DhakaDhaka 1000Bangladesh

The non-Newtonian effect in the boundary layer flow over a horizontal elliptical cylinder is investigated numerically. A modified power-law viscosity model is used to correlate the non-Newtonian characteristics of the fluid flow. For natural convectionflows, the surface of the cylinder is maintained by the uniform surface temperature(UST)or the uniform heat flux(UHF) condition. The governing equations corresponding to theflow are first transformed into a dimensionless non-similar form using suitable transformations. The resulting equations are solved numerically by an efficient finite difference scheme. The numerical results are presented for the skin friction coefficient and the local Nusselt number with the eccentric angle for different values of the power-law index n. The local skin friction coefficient and the local Nusselt number are found to be higher and lower, respectively, for the shear thickening fluids(n > 1) than the other fluids(n≤1).The effects of different elliptical configurations on the average Nusselt number are also presented and discussed for both conditions of the surface temperature.

关键词： non-Newtonian fluid free convection boundary layer elliptical cylinder

Entropy generation analysis from the time-dependent quadratic combined convective flow with multiple diffusions and nonlinear thermal radiation

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Chinese Journal of Chemical Engineering 2023年第1期53卷 46-55页

作者： p.m.patil Bharath Goudar Department of mathematics Karnatak UniversityPavate NagarDharwad 580003India Wrangler Dr.D.C.pavate Institute of mathematical Sciences Karnatak UniversityDharwad 580003India

Diffusions of multiple components have numerous applications such as underground water flow, pollutant movement, stratospheric warming, and food processing. particularly, liquid hydrogen is used in the cooling process of the aeroplane. Further, liquid nitrogen can find applications in cooling equipment or electronic devices, i.e., high temperature superconducting(HTS) cables. So, herein, we have analysed the entropy generation(EG), nonlinear thermal radiation and unsteady(time-dependent) nature of the flow on quadratic combined convective flow over a permeable slender cylinder with diffusions of liquid hydrogen and nitrogen. The governing equations for flow and heat transfer characteristics are expressed in terms of nonlinear coupled partial differential equations. The solutions of these equations are attempted numerically by employing the quasilinearization technique with the implicit finite difference approximation. It is found that EG is minimum for double diffusion(liquid hydrogen and heat diffusion)than triple diffusion(diffusion of liquid hydrogen, nitrogen and heat). The enhancing values of the radiation parameter R_(d) and temperature ratio θ_(w) augment the fluid temperature for steady and unsteady cases as well as the local Nusselt number. Because, the fluid absorbs the heat energy released due to radiation, and in turn releases the heat energy from the cylinder to the surrounding surface.

关键词： Unsteady flow Entropy Radiation Quasilinearization technique Numerical analysis Quadratic combined convection