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Asian Pacific Journal of Tropical Medicine 2015年第1期8卷 24-28页

作者： Mohammad Kargar maryam homayoon Department of Microbiology Islamic Azad University Young Reseasrchers and Elite Club Marvdasht BranchIslamic Azad University

Objective:To survey the prevalence severe diarrhea arising from these bacteria in children under 5 years old in Marvdasht.Methods:In this study faecal sample from 615 children aged <5years old who were hospitalized lor gastroenteritis in Fars hospitals in Iran were collected and then enriched in Escherichia coli(E.coli) broth and modified tryplone soy broth with novobiocin media,fermentation of sorbitol,lactose and β— glucoronidase activity of isolated strains was examined by CT—SMAC,VRBA and chromogenic media respectively.Then isolation of E.coli O157:H7 have been confirmed with the use of specific antisera and with multiplex PCR method presence of virulence genes including:xtx_1.stx_2,eae.A.hly has been analyzed.Results:E.coli O157:H7 was detected in 7(1.14%) stool specimens.A significanl difference was seen between detection rale of isolated bacteria from age groups 18-23 months and other age groups(P=0.004).Out of considered virulence genes.only 1 of the isolated strains(0.16%)he stx,and eaeA genes were seen and also all isolated hacleria had resistance to penicillin,ampicillin and erythromycin antibiotics.Conclusions:We found thai children < 2 years of age were at highest risk of infection with E.coli O157:H7.Regarding severity of E.coli O157:H7 pathogenesis,low infectious dose and lack of routine assay for detection ol these bacleria in clinical laboratory,further and completed studies on diagnosis and genolyping of this E.coli O157:H7 strain has been recommended.

关键词： Escherichia coli O157:H7 Acute gastroenteritis Virulence genes Multiplex PCR

Adjuvant activity of Pasteurella multocida A strain,Pasteurella multocida B strain and Salmonella typhimurium bacterial DNA on cellular and humoral immunity responses against Pasteurella multocida specific strain infections in Balb/c mice

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Asian Pacific Journal of Tropical Medicine 2018年第5期11卷 336-341页

作者： maryam homayoon Yahya Tahamtan Mohammad Kargar Seyed Mohammad Hossein Hosseini Abbas Akhavan Sepahy Department of Biology Science and Research BranchIslamic Azad University Department of Microbiology Shiraz BranchRazi Vaccine and Serum Research InstituteAgriculture ResearchEducation and Extension Organization Department of Microbiology Jahrom Branch Islamic Azad University Department of Microbiology Tehran North BranchIslamic Azad University

Objective: To evaluate the effects of Pasteurella multocida(P. multocida) vaccines on the expression and release of antibodies, interleukin(IL)-6 and IL-12 by serum. Methods: Balb/c mice were immunized with two formalin and iron inactivated vaccine doses within 2 weeks. The vaccines were adjuvant with P. multocida A strain, P. multocida B strain and Salmonella typhimurium bacterial DNA(AbDNA, BbDNA and SbDNA for short, respectively). The animals were challenged 4 weeks after immunization. Blood of mice was collected to detect the change of specific antibody, IL-6, and IL-12 using ELISA. Results: The specific antibody and interleukins in the immunized group increased significantly compared to the control mice after vaccination and challenge(P<0.05). The highest release of these cytokines was obtained by P.multocida inactivated with iron and adjuvant with AbDNA at a concentration of 25 μg/mL. The antibody titer peak was 0.447 in mice vaccinated with iron-killed whole-cell antigen adjunct with AbDNA. The time-courses of release showed that bacterial DNA was able to stimulate IL-6 and IL-12 production more than alum(P<0.05). Conclusions: Our findings introduce that bacterial DNA is capable of releasing an immunological response with several cytokines.These indicate that bacterial DNA entrapped with killed P. multocida antigen is a new and effective adjuvant to enhance specific immunity and resistance of animal against the infectious pathogen, which could simplify the development of highly promising strong adjuvant.

关键词： Pasteurella multocida Bacterial DNA Adjuvant activity Vaccine Immunity Balb/c mice

A Novel Metaheuristic Algorithm: The Team Competition and Cooperation Optimization Algorithm

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Computers, Materials & Continua 2022年第11期73卷 2879-2896页

作者： Tao Wu Xinyu Wu Jingjue Chen Xi Chen Amir homayoon Ashrafzadeh School of Computer Science Chengdu University of Information TechnologyChengdu610225China School of Computer Science and Engineering Southwest Minzu UniversityChengdu610041China CSIT Department School of ScienceRMIT UniversityMelbourne3058Australia

Metaheuristic algorithm is a generalization of heuristic algorithm that can be applied to almost all optimization problems.For optimization problems,metaheuristic algorithm is one of the methods to find its optimal solution or approximate solution under limited conditions.Most of the existing metaheuristic algorithms are designed for serial systems.Meanwhile,existing algorithms still have a lot of room for improvement in convergence speed,robustness,and performance.To address these issues,this paper proposes an easily parallelizable metaheuristic optimization algorithm called team competition and cooperation optimization(TCCO)inspired by the process of human team cooperation and competition.The proposed algorithm attempts to mathematically model human team cooperation and competition to promote the optimization process and find an approximate solution as close as possible to the optimal solution under limited conditions.In order to evaluate the performance of the proposed algorithm,this paper compares the solution accuracy and convergence speed of the TCCO algorithm with the Grasshopper Optimization Algorithm(GOA),Seagull Optimization Algorithm(SOA),Whale Optimization Algorithm(WOA)and Sparrow Search Algorithm(SSA).Experiment results of 30 test functions commonly used in the optimization field indicate that,compared with these current advanced metaheuristic algorithms,TCCO has strong competitiveness in both solution accuracy and convergence speed.

关键词： Optimization metaheuristic algorithm

Detailed seismic risk analysis of electrical substation equipment using a reliability based approach

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 495-511页

作者： Amir Ghahremani Baghmisheh Milad Khodaei Ali Zare Feiz Abadi homayoon E.Estekanchi Department of Civil Engineering University of British ColumbiaVancouver V6T 2B8Canada Department of Civil Engineering University of TabrizTabriz 51666Iran Department of Civil Engineering Sharif University of TechnologyTehran 11155-9313Iran

This paper proposes a risk analysis framework for substation structures based on reliability methods.Even though several risk assessment approaches have been developed for buildings,detailed risk analysis procedures for infrastructure components have been lacking in prior studies.The proposed framework is showcased by its application to a system of interconnected structures at a power substation in Tehran.Finite element models of structures are developed and validated in accordance with previous experiments.The uncertainties in the material,mass,and geometric properties of structures are described by random variables that are input to the finite element model.An artificial ground motion model is employed to comprehensively consider uncertainty in ground motion.Monte Carlo sampling is subsequently conducted on the library of probabilistic models.The analysis resulted in the loss distribution in the life cycle of structures.Additionally,the loss associated with six earthquake scenarios having specific magnitudes and return periods is computed.The application provides insight into the most vulnerable equipment in the considered system.Furthermore,introduced risk measures can guide stakeholders to make risk-based decisions to optimize design or prioritize a retrofit of infrastructure components under conditions of uncertainty.

关键词： seismic risk reliability analysis infrastructure components loss estimation uncertainty

New empirical model to evaluate groundwater flow into circular tunnel using multiple regression analysis

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International Journal of Mining Science and Technology 2017年第3期27卷 415-421页

作者： Farhadian Hadi Katibeh homayoon Departmen of Mining Engineering Faculty of Engineering University of Birjand Birjand Iran Department of Mining and Metallurgical Engineering Amirkabir University of Technology (Tehran Polytechnic) Tehran Iran

There are various analytical, empirical and numerical methods to calculate groundwater inflow into tunnels excavated in rocky media. Analytical methods have been widely applied in prediction of groundwater inflow to tunnels due to their simplicity and practical base theory. Investigations show that the real amount of water infiltrating into jointed tunnels is much less than calculated amount using analytical methods and obtained results are very dependent on tunnel‘s geometry and environmental situations.In this study, using multiple regression analysis, a new empirical model for estimation of groundwater seepage into circular tunnels was introduced. Our data was acquired from field surveys and laboratory analysis of core samples. New regression variables were defined after perusing single and two variables relationship between groundwater seepage and other variables. Finally, an appropriate model for estimation of leakage was obtained using the stepwise algorithm. Statistics like R, R^2, R_P^2 and the histogram of residual values in the model represent a good reputation and fitness for this model to estimate the groundwater seepage into tunnels. The new experimental model was used for the test data and results were satisfactory. Therefore, multiple regression analysis is an effective and efficient way to estimate the groundwater seepage into tunnels.

关键词：多元回归分析法圆形隧道地下水流经验模型多元回归分析方法数值计算方法地下水渗流评价

Estimating seismic demand parameters using the endurance time method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 616-626页

作者： Ramin MADARSHAHIAN homayoon ESTEKANCHI Akbar MAHVASHMOHAMMADI Department of Civil Engineering Sharif University of Technology ATLSS Center Department of Civil and Environmental EngineeringLehigh University

The endurance time (ET) method is a time history based dynamic analysis in which structures are subjected to gradually intensifying excitations and their performances are judged based on their responses at various excitation levels. Using this method, the computational effort required for estimating probable seismic demand parameters can be reduced by an order of magnitude. Calculation of the maximum displacement or target displacement is a basic requirement for estimating performance based on structural design. The purpose of this paper is to compare the results of the nonlinear ET method with the nonlinear static pushover (NSP) method of FEMA 356 by evaluating performances and target displacements of steel frames. This study will lead to a deeper insight into the capabilities and limitations of the ET method. The results are further compared with those of the standard nonlinear response history analysis. We conclude that results from the ET analysis are in proper agreement with those from standard procedures.

关键词： Endurance time(ET) method Nonlinear static pushover(NSP) Nonlinear dynamic analysis(NDA) Target displacement

Design of a heterosubtypic epitope-based peptide vaccine fused with hemokinin-1 against influenza viruses

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Virologica Sinica 2015年第3期30卷 200-207页

作者： Shahla Shahsavandi Mohammad Majid Ebrahimi Kaveh Sadeghi homayoon Mahravani Razi Vaccine & Serum Research Institute Karaj 31975 Iran

Influenza viruses continue to emerge and re-emerge, posing new threats for public health. Control and treatment of influenza depends mainly on vaccination and chemoprophylaxis with approved antiviral drugs. Identification of specific epitopes derived from influenza viruses has significantly advanced the development of epitope-based vaccines. Here, we explore the idea of using HLA binding data to design an epitope-based vaccine that can elicit heterosubtypic T-cell responses against circulating H7N9, H5N1, and H9N2 subtypes. The hemokinin-1(HK-1) peptide sequence was used to induce immune responses against the influenza viruses. Five conserved high score cytotoxic T lymphocyte(CTL) epitopes restricted to HLA-A*0201-binding peptides within the hemagglutinin(HA) protein of the viruses were chosen, and two HA CTL/HK-1 chimera protein models designed. Using in silico analysis, which involves interferon epitope scanning, protein structure prediction, antigenic epitope determination, and model quality evaluation, chimeric proteins were designed. The applicability of one of these proteins as a heterosubtypic epitopebased vaccine candidate was analyzed.

关键词： epitope-based vaccine hemokinin-1 heterosubtypic immunity influenza virus

A method for matching response spectra of endurance time excitations via the Fourier transform

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Earthquake Engineering and Engineering Vibration 2020年第3期19卷 637-648页

作者： Mohammadreza Mashayekhi homayoon EEstekanchi Hassan Vafai Department of Civil Engineering Sharif University of TechnologyTehranIran

The endurance time(ET)method is a dynamic analysis in which structures are subjected to intensifying excitations,also known as ET excitation functions(ETEF).The ET method is a tool for structural response prediction.The main advantage of the ET method over conventional approaches is its much lower demand for computational efforts.The concept of acceleration spectra is used in generating existing ETEFs.It is expected that ETEF acceleration spectra increase consistently with time and remain proportional to a target spectrum.Nonlinear unconstrained optimization is commonly used to generate ETEFs.Generating new ETEFs is a complicated time-consuming mathematical problem.If the target acceleration spectrum changes,new ETEFs must be generated.This study intends to modify existing ETEFs to be compatible with a desired acceleration spectrum.This process,called spectral matching,obviates the need for using the complicated generating procedure in simulating new ETEFs.ETEFs spectral matching is introduced in this paper for the first time.A Fourier-based method for ETEFs spectral matching is proposed.This algorithm is then applied in a case study.Results are presented to prove the efficiency of the algorithm.

关键词： spectrum. excitation acceleration

Omeprazole-based triple therapy with low-versus high-dose of clarithromycin plus amoxicillin for H pylori eradication in Iranian population

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World Journal of Gastroenterology 2007年第6期13卷 930-933页

作者： Ali Asghar Keshavarz homayoon Bashiri Mahtab Rahbar Department of Gastroenterology and Hepatology Emam Reza Hospital Kermanshah University of Medical Sciences Kermanshah Iran Department of Internal Medicine Emam Reza Hospital Kermanshah Iran Department of Pathology Emam Reza Hospital Kermanshah Iran

AIM: To investigate the efficacy and tolerability of H pylori eradication in an omeprazole-based triple therapy with high-and low-dose of clarithromycin and amoxicillin. METHODS: One hundred and sixty H pylori positive patients were randomly assigned to two groups based on the following 2 wk investigation; (1) group A or low-dose regimen received omeprazole 20 mg b.i.d, clarithromycin 250 mg b.i.d and amoxicillin 500 mg b.i.d; and (2) group B or high-dose regimen received omeprazole 20 mg b.i.d, clarithromycin 500 mg b.i.d and amoxicillin 1000 mg b.i.d. During the study H pylori status was assessed by histology and rapid urease test prior and by 13C-urea breath test 6 wk after the therapy. Standard questionnaires were administered to determine the compliance to treatment and possible adverse events of therapy. Data were subject to χ2 to compare the eradication rates in the two groups. The significant level of 95% (P ≤ 0.05) was considered statistically different. RESULTS: We found that the per-protocol eradication rate was 88% (68/77) in group A, and 89% (67/75) in group B. The intension-to-treat eradication rate was 85% (68/80) in group A and 83.75% (67/80) in group B. Overall adverse events were 26% in group A and 31% in group B. The adverse events were generally mild in nature and tolerated well in both groups with a compliance of 98% in group A vs 96% in group B. CONCLUSION: The omeprazole-based low dose regimen of clarithromycin and amoxicillin for two weeks in H pylori eradication is as effective as high dose regimen in Iranian population.

关键词：伊朗人群幽门螺杆菌根除术三重治疗奥美拉唑克拉霉素药物剂量阿莫西林

Tunable graphene-based mid-infrared band-pass planar filter and its application

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Chinese Physics B 2018年第8期27卷 290-296页

作者： Somayyeh Asgari Hossein Rajabloo Nosrat Granpayeh homayoon Oraizi Center of Excellence in Electromagnetics Optical Communication Laboratory Faculty of Electrical EngineeringK N Toosi University of Technology Young Researchers and Elite Club Azadshahr Branch Islamic Azad University Department of Electrical Engineering Iran University of Science and Technology

We have designed and proposed the edge modes supported by graphene ribbons and the planar band-pass filter consist- ing of graphene ribbons coupled to a graphene ring resonator by using the finite-difference time-domain numerical method. Simulation results show that the edge modes improve the electromagnetic coupling between devices. This structure works as a novel, tunable mid-infrared band-pass filter. Our studies will benefit the fabrication of planar, ultra-compact nano-scale devices in the mid-infrared region. A power splitter consisting of two output ribbons that is useful in photonic integrated devices and circuits is also designed and simulated. These devices are useful for designing ultra-compact planar devices in photonic integrated circuits.

关键词： band-pass filter graphene surface plasmons power splitter