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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 903-915页

作者： Meysam Ramezani Akbar Bathaei amir k.ghorbani-tanha School of Civil Engineering College of Engineering University of Tehran

High-rise buildings are usually considered as flexible structures with low inherent damping. Therefore, these kinds of buildings are susceptible to wind-induced vibration. Tuned Mass Damper（TMD） can be used as an effective device to mitigate excessive vibrations. In this study, Artificial Neural Networks is used to find optimal mechanical properties of TMD for high-rise buildings subjected to wind load. The patterns obtained from structural analysis of different multi degree of freedom（MDF） systems are used for training neural networks. In order to obtain these patterns, structural models of some systems with 10 to 80 degrees-of-freedoms are built in MATLAB/SIMULINk program. Finally, the optimal properties of TMD are determined based on the objective of maximum displacement response reduction. The Auto-Regressive model is used to simulate the wind load. In this way, the uncertainties related to wind loading can be taken into account in neural network’s outputs. After training the neural network, it becomes possible to set the frequency and TMD mass ratio as inputs and get the optimal TMD frequency and damping ratio as outputs. As a case study, a benchmark 76-story office building is considered and the presented procedure is used to obtain optimal characteristics of the TMD for the building.

关键词： artificial neural networks tuned mass damper wind load auto-regressive model optimal frequency anddamping

Optimum placement and characteristics of velocity-dependent dampers under seismic excitation

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 403-414页

作者： Seyed Amin Mousavi amir k.ghorbani-tanha R&D Department Sabok Sazan Sarie Engineering Company School of Civil Engineering College of EngineeringUniversity of Tehran

In this study, through novel drift-based equations of motion in the frequency domain, optimum placement and characteristics of linear velocity-dependent dampers are investigated. In this study, the sum of the square of the absolute values of transfer matrix elements for interstory drifts is considered as the optimization index. Optimum placement and characteristics of dampers are simultaneously obtained by minimizing the optimization index through an incremental procedure. In each step of the procedure, a predefined value is considered as the damper characteristic. The optimum story for this increment is selected such that it leads to a minimum value for the optimization index. The procedure is repeated for the next increments until the optimization index meets its target value, which is obtained according to the desired damping ratio for the overall structure. In other words, the desired overall damping ratio is the input to the proposed procedure, and the optimal placement and characteristics of the dampers are its output. It is observed that the optimal placement of a velocitydependent damper depends on the damping coefficient of the added damper, frequency of the excitation, and distribution of the mass, stiffness, and inherent damping of the main structure.

关键词： passive control velocity-dependent damper optimum placement optimum damping transfer matrix storydamping coefficient

Closure to“Discussion on‘Optimum placement and characteristics of velocity-dependent dampers under seismic excitation' by SA Mousavi and Ak.ghorbani-tanha”by Izuru Takewaki

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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 681-682页

作者： Seyed Amin Mousavi amir k.ghorbani-tanha School of Civil Engineering College of EngineeringUniversity of Tehran

The authors would like to thank the discusser for his considerations and comments. The discusser believes that some of the derived formulations need to be referred to his previously published works and also some relat... 详细信息

关键词： Optimum placement and characteristics of velocity-dependent dampers under seismic excitation by SA Mousavi and Ak.ghorbani-tanha Closure to

Semi-active fuzzy control of Lali Cable-Stayed Bridge using MR dampers under seismic excitation

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 706-721页

作者： Sajad JAVADINASAB HORMOZABAD amir k.ghorbani-tanha School of Civil Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Seismic control of cable-stayed bridges is of paramount importance due to their complex dynamic behavior,high flexibility,and low structural damping.In the present study,several semi-active Fuzzy Control Algorithms(FCAs)for vibration mitigation of Lali Cable-Stayed Bridge are devised.To demonstrate the efficiency of the algorithms,a comprehensive nonlinear 3-D model of the bridge is created using OpenSees.An efficient method for connecting MATLAB and OpenSees is devised for applying FCAs to the structural model of the bridge.Two innovative fuzzy rulebases are introduced.A total of six different fiuzzy rule-bases are utilized.The efficiency of the FCAs is evaluated in a comparative manner.The performance of fuzzy control systems is also compared with a sky-hook and a passive-on system.Moreover,the sensitivity of efficiency of control systems to the peak ground acceleration is evaluated qualitatively.In addition,the effect of time lag is also investigated.This study thoroughly examines the efficiency of the FCAs in different aspects.Therefore,the results can be regarded as a general guide to design semi-active fuzzy control systems for vibration mitigation of cable-stayed bridges.

关键词： semi-active control Fuzzy Control Algorithm cable-stayed bridge MR damper Lali Bridge

amplitude modulation;high-frequency modulation;autoresonance;ion acoustic wave

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High Power Laser Science and Engineering 2024年第1期12卷 74-83页

作者： Michael Valdman amir Hen Gilad Marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave

Synergistic effect of adsorption and photocatalytic degradation of oilfield-produced water by electrospun photocatalytic fibers of Polystyrene/Nanorod-Graphitic carbon nitride

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Journal of Environmental Sciences 2024年第7期141卷 287-303页

作者： Parisa Azmoon Mehrdad Farhadian Alireza Pendashteh amir H.Navarchian Department of Chemical Engineering Faculty of EngineeringUniversity of IsfahanIsfahanIran Department of Chemical Engineering Faculty of EngineeringUniversity of GuilanRashtIran Department of Water and Environmental Engineering Caspian Sea Basin Research CenterUniversity of GuilanRashtIran

Graphitic carbon nitride with nanorod structure(Nr-GCN)was synthesized using melamine as a precursor without any other reagents by hydrothermal pretreatment method.XRD,FTIR,SEM,N_(2)adsorption-desorption from BET,UV-Vis DRS spectroscopy,and photoluminescence were used to characterize the prepared samples.Also,the photoelectrochemical behavior of nanoparticles was studied by photocurrent transient response and cyclic voltammetry analysis.Polystyrene(PS)fibrous mat was fabricated by electrospinning technique and used as a support for the stabilization of the nanoparticles.The performance of the synthesized nanoparticles and photocatalytic fibers(PS/Nr-GCN)was evaluated in oilfield-produced water treatment under visible light irradiation.During this process,oil contaminants were adsorbed by hydrophobic polystyrene fibers and simultaneously degraded by Nr-GCN.The removal efficiency of chemical oxygen demand(COD)has been obtained 96.6%and 98.4%by Nr-GCN and PS/Nr-GCN,respectively,at the optimum conditions of pH4,photocatalyst dosage 0.5 g/L,COD initial concentration 550 mg/L,and illumination time 150 min.The gas chromatography-mass spectroscopy analysis results showed 99.3%removal of total petroleum hydrocarbons using photocatalytic fibers of PS/Nr-GCN.The results demonstrated that the GCN has outstanding features like controllable morphology,visible-light-driven,and showing high potential in oily wastewater remediation.Moreover,the synergistic effect of adsorption and photocatalytic degradation is an effective technique in oilfield-produced water treatment.

关键词： Graphitic carbon nitride(GCN) Nanorod structure Polystyrene fibrous mat Photocatalytic fibers Oilfield-produced water(OPW)

CRISPR,CAR-T,and Nk:Current applications and future perspectives

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Genes & Diseases 2024年第4期11卷 246-257页

作者： Mohadeseh khoshandam Hossein Soltaninejad amir Ali Hamidieh Saman Hosseinkhani Department of Reproductive Biology Academic Center for EducationCultureand Research(ACECR)Qom branch***Iran National Institute of Genetic Engineering and Biotechnology(NIGEB) Tehran 14965/161Iran Department of stem cells technology and Tissue Regeneration Faculty of Interdisciplinary Science and TechnologiesTarbiat Modares UniversityTehran 15614Iran Pediatric Cell Therapy and Gene Therapy Research Center GeneCell&Tissue Research InstituteTehran University of Medical SciencesTehran ***Iran Department of Biochemistry Faculty of Biological SciencesTarbiat Modares UniversityTehran 15614Iran

Chimeric antigen receptor T(CAR-T)cell therapy represents a breakthrough in personalized cancer treatments.In this regard,synthetic receptors comprised of antigen recognition domains,signaling,and stimulatory domains are used to reprogram T-cells to target tum or cells and destroy them.Despite the success of this approach in refractory B-cell malignancies,the optimal potency of CAR T-cell therapy for many other cancers,particularly solid tumors,has not been validated.Natural killer cells are powerful cytotoxic lymphocytes specialized in recognizing and dispensing the tumor cells in coordination with other anti-tumor immunity cells.Based on these studies,many investigations are focused on the accurate designing of CAR T-cells with clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system or other novel gene editing tools that can induce hereditary changes with or without the presence of a double-stranded break into the genome.These methodologies can be specifically focused on negative controllers of T-cells,induce modifications to a particular gene,and produce reproducible,safe,and powerful allogeneic CAR T-cells for on-demand cancer immunotherapy.The improvement of the CRISPR/Cas9 innovation offers an adaptable and proficient gene-editing capability in activating different pathways to help natural killer cells interact with novel CARs to particularly target tumor cells.Novel achievements and future challenges of combining next-generation CRISPR-Cas9 gene editing tools to optimize CAR T-cell and natural killer cell treatment for future clinical trials toward the foundation of modern cancer treatments have been assessed inthis review.

关键词： Cancer CAR T-cell CRISPR Gene editing Immunotherapy Nk cell

Clinical applications of the CRISPR/Cas9 genome-editing system: Delivery options and challenges in precision medicine

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Genes & Diseases 2024年第1期11卷 268-282页

作者： Mohadeseh khoshandam Hossein Soltaninejad Marziyeh Mousazadeh amir Ali Hamidieh Saman Hosseinkhani Department of Reproductive Biology Academic Center for EducationCultureand Research(ACECR)Qom BranchQom ***Iran National Institute of Genetic Engineering and Biotechnology(NIGEB) Tehran 14155-6463Iran Faculty of Interdisciplinary Science and Technology Tarbiat Modares UniversityTehran 14117-13116Iran Pediatric Cell and Gene Therapy Research Center GeneCell&Tissue Research InstituteTehran UniversityofMedical SciencesTehran14155-6559Iran Department of Nanobiotechnology Faculty of Biological SciencesTarbiat Modares UniversityTehran 14117-13116Iran Department of Biochemistry Faculty of Biological SciencesTarbiat Modares UniversityTehran 14117-13116Iran

CRISPR/Cas9 is an effective gene editing tool with broad applications for the pre-vention or treatment of numerous diseases.It depends on CRiSPR(clustered regularly inter-spaced short palindromic repeats)as a bacterial immune system and plays as a gene editing tool.Due to the higher specificity and efficiency of CRISPR/Cas9 compared to other editing ap-proaches,it has been broadly investigated to treat numerous hereditary and acquired ill-nesses,including cancers,hemolytic diseases,immunodeficiency disorders,cardiovascular diseases,visual maladies,neurodegenerative conditions,and a few X-linked disorders.CRISPR/Cas9 system has been used to treat cancers through a variety of approaches,with sta-ble gene editing techniques.Here,the applications and clinical trials of CRisPR/Cas9 in various illnesses are described.Due to its high precision and efficiency,CRISPR/Cas9 strategies may treat gene-related illnesses by deleting,inserting,modifying,or blocking the expression of specific genes.The most challenging barrier to the in vivo use of CRISPR/Cas9 like off-target effects will be discussed.The use of transfection vehicles for CRISPR/Cas9,including viral vectors(such as an Adeno-associated virus(AAV),and the development of non-viral vectors is also considered.

关键词： Clinical trials CRISPR/Cas9 Gene therapy Non-viral vectors Viral vectors

Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs

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Petroleum Science 2024年第2期21卷 951-961页

作者： amir Mohammad Zamani Ashkan Moslemi kamran Hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate reservoirs.Thermal gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth gum.Subsequently,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay particles.In various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,respectively.The entire experiment was conducted at 25,50,and 75℃,respectively.According to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio improvement.Among clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all temperatures.Considerable wettability alteration was also observed in the case of natural polymer and illite NPs.Illite in combination with natural polymer showed an ability in reducing IFT.Finally,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

A rare complication of measles infection presented with subacute sclerosing panencephalitis: Report of two cases in India

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Asian Pacific Journal of Tropical Medicine 2024年第4期17卷 184-187页

作者： Razeen Fatima amir Husain Iram Tabish Department of Medicine JN Medical CollegeAMUAligarhIndia

Rationale:Subacute sclerosing panencephalitis(SSPE)is a progressive neurological disorder caused by persistent measles virus infection.SSPE predominantly affects children and adolescents.The symptoms usually develop 6-15 years after measles infection and ultimately leading to death in many cases.Patient concerns:Patient 1 presented with cognitive decline and myoclonus and the Patient 2 presented with diminution of vision with myoclonic jerks.Diagnosis:Based on the clinical features with a characteristic electroencephalogram pattern and the presence of a high titer of anti-measles IgG in serum and cerebrospinal fluid,these patients were diagnosed as SSPE.Interventions:Antiepileptics were started for controlling myoclonus along with supportive treatment.Outcomes:Both patients were discharged on antiepileptics and supportive care.Lessons:Whenever there are unusual clinical manifestations with unknown vaccination status,SSPE can be suspected and the cerebrospinal fluid should be examined for anti-measles antibodies.Our case study also highlights the importance of universal coverage of measles vaccination.To reduce the incidence of measles and associated deaths,it is important to maintain a high level of immunization coverage for the measles vaccine and to strengthen all the integral components of the national immunization program.

关键词： Subacute sclerosing panencephalitis Measles Myoclonus Electroencephalogram Cerebrospinal fluid