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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

Electro-spray of high viscous liquids for producing mono-sized spherical alginate beads

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Particuology 2008年第4期6卷 271-275页

作者： Hamid moghadam Mohsen samimi abdolreza samimi Mohamad Khorram Chemical Engineering Department University of Sistan and Baluchestan

Alginate beads, often used for controlled release of enzymes and drugs, are usually produced by spraying sodium alginate liquid into a gelling agent using mechanical vibration nozzle or air jet. In this work an alternative method of electro-spray was employed to form droplets with desired size from a highly viscous sodium alginate solution using constant DC voltage. The droplets were then cured in a calcium chloride solution. The main objective was to produce mono-sized beads from such a highly viscous and non-Newtonian liquid (1000–5000 mPa s). The effects of nozzle diameter, flow rate and concentration of liquid on the size of the beads were investigated. Among the parameters studied, voltage had a pronounced effect on the size of beads as compared to flow rate, nozzle diameter and concentration of alginate liquid. The size of beads was reduced to a minimum value with increasing the voltage in the range of 0–10 kV. At the early stages of voltage increase (i.e. up to about 4 kV), the rate of size reduction was relatively low, while the dripping mode dominated. However, in the middle part of the range of applied voltage, where the rate of size reduction was high (i.e. about 4–7 kV), an unstable transition occurred between dripping and jetting. At the end part of the range (i.e. 7–10 kV) jet mode of spray was observed. Increasing the height of fall of the droplets was found to improve the sphericity of the beads, because of the increased time of flight for the droplets. This was especially identifiable at higher concentrations of the alginate liquid (i.e. 3 w/v%).

关键词： Electro-spray Highly viscous liquid Constant DC electric field Alginate beads

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

Modeling and simulation of induction motor drive system to investigate and mitigate of PWM inverter’s adverse effects

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Journal of Harbin Institute of Technology(New series) 2007年第1期14卷 83-88页

作者： EsMAELI abdolreza 孙力 Dept. of National Radiation Protection Iranian Nuclear Regulatory Authority

Modeling and simulation of induction motor drive system to investigate and mitigate the adverse effects of PWM inverter based on analysis, modeling and simulation are presented. The estimation of conducted disturbances and other adverse effects of PWM inverter by simulation offer a considerable gain from the economic point of view. For an accurate model of the motor drive system including mains, rectifier, inverter, motor and its long cables, the high frequency parasitic current paths are taken into account. The novel model and its parasitic values for three-phase induction motor system are presented. Finally a new solution for suppressing EMI, common mode voltage, leakage current, bearing current and shaft voltages is proposed and the results show the excellent performances of proposed solution including active and passive filters.

关键词： induction motor PWM inverter adverse effects EMC high frequency model

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

Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2917-2918页

作者： Leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating

The Maastrichtian-Danian in the sW Zagros Fold-Thrust Belt(s. Iran):An Integration of Planktonic Foraminiferal Biostratigraphy and Gamma-Ray spectrometry

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Acta Geologica sinica(English Edition) 2020年第5期94卷 1339-1363页

作者： abdolreza MOGHADDAsI Hossein VAZIRI-MOGHADDAM Ali sEYRAFIAN Department of Geology Faculty of SciencesUniversity of IsfahanIsfahanIran

In this study, the Maastrichtian-Danian boundary was measured and sampled in two stratigraphic sections, the north and south flanks of the Dehnow anticline in Coastal Fars, southern Iran. This boundary was also investigated in the drilled exploratory well-1 in the same region. The lithology of the Maastrichtian-Danian deposits consists of glauconitic, phosphatic argillaceous limestones and marlstones. 30 genera and 77 species of planktonic foraminifera have been determined. The recognized biozones are the Gansserina gansseri Interval Zone, and the Contusotruncana contusa Interval Zone, which indicates latest Campanian to middle Maastrichtian age for the upper part of the Gurpi Formation. In addition, the Eoglobigerina edita(P1) Partial Range Zone, Praemurica uncinata(P2) Lowest Occurrence Zone, Morozovella angulata(P3) Lowest Occurrence Zone and Globanomalina psudomenardii(P4) Taxon Range Zone represent a Danian to Thanetian age for the lower part of the Pabdeh Formation. From the absence of the Abathomphalus mayaroensis Interval Zone, Pseudoguembelina hariaensis Interval Zone, Pseudotextularia elegans Interval Zone, Plummerita hantkeninoides Interval Zone, Guembelitria cretacea(P0) Partial Range Zone and Parvularugoglobigerina eugubina(Pα) Total Range Zone, it can be deduced that there is a paraconformity across the Maastrichtian–Danian boundary in the studied area, this hiatus encompassing the late Maastrichtian and the earliest Danian. Danian deposits from the study area contain reworked glauconitized macrofossils, planktonic and benthic foraminifera of the Cretaceous. The obtained surface gamma-ray spectrometry logs resemble the exploratory well-1 gamma-ray wireline log.

关键词： biostratigraphy planktonic foraminifera gamma-ray spectrometry Maastrichtian-Danian Zagros Iran

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

Eigen-spectra in the Dirac-attractive radial problem plus a tensor interaction under pseudospin and spin symmetry with the sUsY approach

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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