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Decoding molecular mechanisms:brain aging and Alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay Ali Syed Hammad Qaiser Mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid bashir Atta-ur-Rahman School of Applied Biosciences(ASAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological Sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

关键词： Alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Thermodynamic Stability, Half-Metallic and Optical Properties of Sc_(2)CoSi [001] Film:a DFT Study

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Communications in Theoretical Physics 2019年第4期71卷 455-462页

作者： Maliheh Amiri Hossein Akbari bashir Nedaee-shakarab Arash Boochani Amin Aminian Yousof Zangeneh Sirvan naderi Department of Physics Kermanshah Branch Islamic Azad University Department of Physics Ardabil Branch Islamic Azad University Department of physics university of Guilan Young Researchers and Elite Club Kermanshah Branch Islamic Azad University

The electronic and optical characteristics of the Sc2 CoSi Heusler with L21 structure and also the surface effect on electronic and optical properties, and the ?lms thermodynamic stability of the [001] direction in four cases including:Sc-Sc, Sc-Co, Sc-Si and Co-Si terminations are studied using the ?rst principles calculations(FPLAPW) within the framework of the density functional theory(DFT). The band structure calculations represent the ferromagnetic halfmetallic properties with 100% spin polarization and 0.54 e V indirect gap in spin down for Sc2 CoSi bulk with optimized lattice parameters of 6.25 A?. The total magnetic moment obtained for this compound is-1.0 μB, which is in accordance with Slater-Pauling rule. The half-metallic(HM) behavior by 100% spin polarization at Fermi level is occurred in the Sc-Si termination with a 0.32 eV gap in down spin. The optical responses have been calculated for the bulk and ScSi termination by a red shift in these parameters and the metallic treatments have been increased. According to the thermodynamic phase diagrams, it is shown the Sc-Si and Sc-Sc terminations are more stable than other terminations.

关键词： half-metalicity DFT thermodynamic stability thin films Heusler alloy first-principles calculations

A method for improving graph queries processing using positional inverted index (P.I.I) idea in search engines and parallelization techniques

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Journal of Central South University 2016年第1期23卷 150-159页

作者： Hamed Dinari Hassan naderi Web and Search Engines Laboratory School of Computer EngineeringIran University of Science and Technology

The idea of positional inverted index is exploited for indexing of graph database. The main idea is the use of hashing tables in order to prune a considerable portion of graph database that cannot contain the answer set. These tables are implemented using column-based techniques and are used to store graphs of database, frequent sub-graphs and the neighborhood of nodes. In order to exact checking of remaining graphs, the vertex invariant is used for isomorphism test which can be parallel implemented. The results of evaluation indicate that proposed method outperforms existing methods.

关键词： graph query processing frequent subgraph graph mining data mining positional inverted index

Influence of Welding Parameters on Microstructure and Mechanical Performance of Resistance Spot Welded High Strength Steels

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 635-640页

作者： H.Ghazanfari M.naderi Department of Mining and Metallurgical Engineering Amirkabir University of Technology (Tehran Polytechnic)

This paper presents an experimental study on physical and mechanical properties of high strength steel plates（AISI 4130） joined by resistance spot welding by means of hardness mapping technique. Welding current and electrode force were selected as experimental parameters. The welded joints were exposed to tensile-shearing tests in order to determine the strength of the welded zones. Hardness and microstructural examinations were carried out in order to examine the influence of welding parameters on the welded joints. Hardness mapping test was conducted on the large area of weld zone, including the heat afected zone and base plate. Hardness map was used to investigate the efects of current on hardness and microstructure in diferent regions of weld. Low electrode force and high welding current, used during the welding, increased the expulsion. An optimum weld quality was obtained by using 6.5 kA weld current. It was found that mechanical performance of resistance spot welded samples is controlled by nugget diameter and expulsion. Results revealed that hardness mapping technique provides one of the best methods for the physical and mechanical understanding of heterogeneous microstructures using hardness criterion.

关键词： Welding current Microstructure Hardness map Expulsion Martensite

SBR COMPOSITES REINFORCED WITH N-ISOPROPYL-N'PHENYL-P-PHENYLENEDIAMINE-MODIFIED CLAY

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Chinese Journal of Polymer Science 2011年第2期29卷 191-196页

作者： Habibollah Baharvand Ghasem naderi Sedigheh Soltani Iran Polymer & Petrochemical Institute TehranP.O.Box 14965/115Iran

SBR compounds including the N-isopropyl-N＇-phenyl-p-phenylenediamine-modified clay（organoclay） were *** of modified clay and antioxidant（IPPD） contents on mechanical and rheological properties of SBR composites were *** results confirmed that the clay was chemically modified by IPPD and changed into an organoclay.X-ray diffraction（XRD） results confirmed the increase in interlayer distance of the clay due to the insertion of *** and cure characteristics of SBR compounds were determined using RPA（Rubber Process Analyzer） and *** time and cure time of SBR compounds decreased with introduction of the *** properties and heat aging resistance of the SBR composites were improved significantly by incorporation of the organoclay.

关键词： SBR Organoclay Mechanical properties Cure characteristics Antioxidant

Improvement in the protective performance and adhesion of polypyrrole coating on AZ31 Mg alloys

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Progress in Natural Science:Materials International 2015年第5期25卷 478-485页

作者： Maryam Hatami Mohsen Saremi Reza naderi School of Metallurgy and Materials Engineering Faculty of Engineering University of Tehran

The electrochemical synthesis of polypyrrole(Ppy) coating on AZ31 magnesium alloy was successfully achieved in a solution containing sodium salicylate and monomer of pyrrole through cyclic voltammetry *** effect of potential range,passivation pretreatment and number of cycles of polymerization on the quality and protective performance of the coatings was evaluated using surface analysis and electrochemical *** taking the advantage of charge transfer resistance,current density,corrosion potential,optical microscopy images and SEM micrographs,the optimum condition of synthesis of a Ppy coating with the best adhesion and corrosion protection was *** optimal PPy coating synthesized over AZ31 increases the polarization resistance and decreases the corrosion current more than one order of magnitude and shift the corrosion potential about 200 mV toward nobler *** SEM studies showed that Ppy coating have cauliflower morphology of Ppy grains with a diameter ranging from 20 nm to 60 nm.

关键词： PolyPyrrole AZ31 Mg Cyclic voltammetry Electropolymerization Corrosion protection

Composition, environment, and economic value of the Permian to Cretaceous coated grains from Zagros and the Persian Gulf

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International Journal of Sediment Research 2023年第3期38卷 316-334页

作者： Mehrangiz naderi-Khujin Vahid Tavakoli Pars Oil and Gas Company School of Geology College of Science University of Tehran

Ooid grainstone/packstone carbonate facies of the Dalan, Kangan, and Arab formations are the main hydrocarbon reservoirs in the Persian Gulf. Based on detailed petrographic and petrophysical analyses,sedimentological and mineralogical features of the Permian to Late Cretaceous carbonate and iron-rich coated grains from Zagros and the Persian Gulf were investigated. Frequent ooids in these formations indicate a high-energy environment and a wave-dominated shallow carbonate platform. Because of wide-spread Permian-Triassic epiric seas and long-lasting periods of arid and hot climate, Permian-Triassic carbonate ooids have more vertical and lateral distribution in comparison with Late Jurassic carbonate ooids. Dolomite, calcite, and anhydrite are the major minerals of carbonate ooid grains. Early Cretaceous iron-rich ooids have been deposited above a major Late Aptian disconformity during the highstand systems tract. Ooid ironstone bulk sample X-ray diffraction(XRD) analysis shows that goethite,siderite, fluorapatite, calcite, quartz, and pyrite are the major phases of ooid ironstone deposits. This layer of iron bearing ooids could have economic importance in its outcrops in the Zagros area. Late Cretaceous iron-rich coated grains(pisoid-oncoids) were deposited above the Sarvak exposure surface during the Late Cretaceous, long-lasting sea-level fall on the Arabian Plate. Boehmite, diaspore, hematite, and goethite are the main minerals of these kind of iron-rich deposits. Late Cretaceous karst-type bauxite deposits have also been reported from different sections of the Zagros area and have economic value for mining.

关键词： Coated grains Depositional conditions Permian Cretaceous Bauxite

Expulsion characterization in resistance spot welding by means of a hardness mapping technique

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International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 894-897页

作者： H.Ghazanfari M.naderi Department of Mining and Metallurgy AmirKabir University of Technology424 Hafez AveTehran 15875-4413 Iran

Expulsion is an undesired event during resistance spot welding because the weld quality deteriorates. It is the ejection of molten metal from the weld nugget which usually occurs due to applying a high current for a short welding time. Expulsion has a significant impact on the final yield strength of the weld, thus the detection and characterization of expulsion events is significant for the quality assurance of resistance spot welds. In this study, hardness mapping, using a scanning hardness machine, was used as a quality assurance technique for re- sistance spot welding. Hardness tests were conducted on a resistance spot welded sample to prepare a hardness map. The test results showed good correlation between the hardness map and metallographic cross sections. The technique also provided further fundamental understand- ing of the resistance spot welding process, especially regarding the occurrence of expulsion in the nugget.

关键词： alloy steel spot welding heat-affected zone hardness mapping

Graphite versus graphene:plasmonic nanopore DNA sequencing

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Optoelectronics Letters 2023年第6期19卷 353-358页

作者： bashir Fotouhi Faculty of Electrical and Computer Engineering University of KurdistanKurdistanIran

The plasmonic-based graphite-and graphene-nanopores have been investigated by employing the hybrid quantum/classical scheme(HQCS).Transverse,longitudinal,and total absorption spectra obtained from HQCS are analyzed for the graphite and graphene *** were examined for each structure in the presence of deoxyribonucleic acid(DNA) *** simple excitation of the total mode in graphene nanopore shows the best selectivity for DNA sequencing.A novel method based on the transverse and longitudinal modes in a time-series approach has been proposed for selectivity *** the proposed time-series method,the outstanding results show that graphite nanopore is more sensitive than and as selective as graphene *** paper suggests that time-step analysis of the plasmonic absorption in the graphite nanopore is a promising method for DNA sequencing.

关键词： graphene method absorption