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Chinese Physics B 2013年第10期22卷 112-118页

作者： s.arbabi moghadam H.Mehraban M.Eshghi Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Physics Department Faculty of SciencesSemnan UniversitySemnanIran Physics Department Imam Hossein Comprehensive UniversityTehranIran

We approximately solve the Dirac equation for attractive radial potential including a Coulomb-like tensor interaction under pseudospin and the spin symmetry limit for any arbitrary spin-orbit quantum number, by employing the supersymmetric （sUsY） quantum mechanics and supersymmetric shape invariance technique. We obtain the energy eigenvalue equation under the pseudospin and spin conditions. some numerical results are compared with those obtained by the Nikiforove-Uvarov （NU） method.

关键词： Dirac equation attractive radial sUsY Coulomb-like tensor potential

At-will chromatic dispersion by prescribing light trajectories with cascaded metasurfaces

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Light(science & Applications) 2020年第1期9卷 1108-1116页

作者： Andrew McClung Mahdad Mansouree Amir arbabi Department of Electrical and Computer Engineering University of Massachusetts Amherst151 Holdsworth WayAmherstMA 01003USA

Chromatic dispersion spatially separates white light into colours,producing rainbows and similar *** to imaging but essential to spectroscopy,chromatic dispersion is the result of material properties in refractive optics and is considered an inherent characteristic of diffractive devices such as gratings and flat ***,we present a fundamental relation connecting an optical system’s dispersion to the trajectories light takes through it and show that arbitrary control over dispersion may be achieved by prescribing specific trajectories,even in diffractive *** cascaded metasurfaces(2D arrays of sub-micron scatterers)to direct light along predetermined trajectories,we present an achromatic twisted metalens and experimentally demonstrate beam deflectors with arbitrary *** new insight and design approach usher in a new class of optical systems with wide-ranging applications.

关键词： dispersion light trajectories

Probabilistic safety assessment of self-centering steel braced frame

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Frontiers of structural and Civil Engineering 2018年第1期12卷 163-182页

作者： Navid RAHGOZAR Nima RAHGOZAR Abdolreza s. moghadam Department of structural Engineering Science and Research Branch Islamic Azad University Tehran Iran structural Engineering Research Center International Institute of Earthquake Engineering and Seismology (IIEES) Tehran Iran

The main drawback of conventional braced frames is implicitly accepting structural damage under the design earthquake load, which leads to considerable economic losses. Controlled rocking self-centering system as a modem low-damage system is capable of minimizing the drawbacks of conventional braced frames. This paper quantifies main limit states and investigates the seismic performance of self-centering braced frame using a Probabilistic safety Assessment procedure. Margin of safety, confidence level, and mean annual frequency of the self-centering archetypes for their main limit states, including PT yield, fuse fracture, and global collapse, are established and are compared with their acceptance criteria. Considering incorporating aleatory examined. Results of the investigation indicate that the provide the adequate margin of safety against exceeding and epistemic uncertainties, the efficiency of the system is design of low- and mid-rise self-centering archetypes could the undesirable limit-states.

关键词： self-centering steel braced frame mean annual frequency safety assessment confidence level margin of safety

Exact solutions of Five Complex Nonlinear schr¨odinger Equations by semi-Inverse Variational Principle

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Communications in Theoretical Physics 2014年第9期61卷 301-307页

作者： Mohammad Najafi somayeh arbabi Medical Biology Research Center Kermanshah University of Medical SciencesKermanshah Iran

In this paper, we establish exact solutions for five complex nonlinear schr¨odinger equations. The semiinverse variational principle(sVP) is used to construct exact soliton solutions of five complex nonlinear schr¨odinger equations. Many new families of exact soliton solutions of five complex nonlinear schr¨odinger equations are successfully obtained.

关键词： two-dimensional schr¨odinger equation three-dimensional schr¨odinger equation unstable schr¨odinger equation

Revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

PML solution of longitudinal wave propagation in heterogeneous media

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 357-368页

作者： Farzanian M. arbabi Freydoon Pak Ronald International Institute of Earthquake Engineering and seismology 26 Arghavan St. North Dibajee Farmanieh Tehran Iran Department of Civi Environmental & Architectural Engineering University of Colorado Boulder CO 80309-0428 United States

This paper describes the development of a model for unbounded heterogeneous domains with radiation damping produced by an unphysical wave absorbing layer. The Perfectly Matched Layer（PML） approach is used along with a displacement-based finite element. The heterogeneous model is validated using the closed-form solution of a benchmark problem： a free rod with two-part modulus subjected to a specified time history. Both elastically supported and unsupported semi-infinite rods with different degrees of inhomogeneity and loading are considered. Numerical results illustrate the effects of inhomogeneity on the response and are compared with those for equivalent homogeneous domains. The effects of characteristic features of the inhomogeneous problem, presence of local maxima and cut-off frequency are determined. A degenerate case of a homogeneous semi-infinite rod on elastic foundations is produced by tending the magnitude of the foundation stiffness to zero. The response of the latter is compared with that of a free rod. The importance of proper selection of the PML parameters to highly accurate and efficient results is demonstrated by example problems.

关键词： heterogeneous latter benchmark illustrate validated modulus coordinates inhomogeneous maxima infinite

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

Deciphering the mechanobiology of microglia in traumatic brain injury with advanced microsystems

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Neural Regeneration Research 2025年第8期20卷 2304-2306页

作者： Anthony Procès sylvain Gabriele Univ.Grenoble Alpes InsermU1216Grenoble Institut des NeurosciencesGrenobleFrance Mechanobiology&Biomaterials Group CIRMAPResearch Institute for BiosciencesUniversity of MonsMonsBelgium

Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary *** minutes ... 详细信息

关键词： traumatic injury damage

Optimization of design parameters for controlled rocking steel braced dual-frames

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Earthquake Engineering and Engineering Vibration 2022年第4期21卷 1053-1068页

作者： sobhan Ghasemi M.Firoozi Nezamabadi Abdolreza s.moghadam Mahmood Hosseini Department of Civil Engineering South Tehran BranchIslamic Azad UniversityTehranIran structural Engineering Research Center International Institute of Earthquake Engineering and Seismology(IIEES)TehranIran

A controlled rocking concentrically steel braced frame(CR-CsBF)is introduced as an alternative to conventional methods to prevent major structural damage during large *** is equipped with elastic post-tensioned(PT)cables and replaceable devices or fuses to provide overturning resistance and dissipate energy,*** CR-CsBFs are not officially legalized in globally valid codes for new buildings,it is expected to be presented in them in the near *** main goal of this study is to determine the optimal design parameters consist of the yield strength and modulus of elasticity of the fuse,the initial force of the PT cable,and the gravity load on the rocking column,considering different heights of the frame,spanning ratios and ground motion types for dual-configuration *** time-history analyses are performed in *** study aims to define the optimal input variables as effective design parameters of CR-CsBFs by comparing four seismic responses consisting of story drift,roof displacement,roof acceleration and base shear,and also using the Euclidean metric optimization *** the previous research,this study is innovative and first of its *** results demonstrate that the optimal design parameters are variable for various conditions.

关键词： self-centering rocking steel braced frame design parameters optimization low damage

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch