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Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

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Chinese Optics Letters 2009年第5期7卷 435-436页

作者： Hassan Kaatuzian seyed Iman taghavi Photonics Research Laboratory Electrical Engineering DepartmentAmirkabir University of Technology

An optical bandwidth analysis of a quantum-well （16 nm） transistor laser with 150-μm cavity length using a charge control model is reported in order to modify the quantum-well location through the base region. At constant bias current, the simulation shows significant enhancement in optical bandwidth due to moving the quantum well in the direction of collector-base junction. No remarkable resonance peak, limiting factor in laser diodes, is observed during this modification in transistor laser structure. The method can be utilized for transistor laser structure design.

关键词： well Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

Preparation and Characterization of Novel Thermostable Polyamides Bearing Different Photoactive Pendent Architectures with Antibacterial Properties

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Chinese Journal of Polymer Science 2016年第6期34卷 766-776页

作者： seyed Mojtaba Amininasab Azad Rashidi Mehdi taghavi Zahed Shami Department of Chemistry University of KurdistanSanandaj 66177-15175Iran Polymer Chemistry Research Laboratory Faculty of ScienceShahid Chamran University of Ahvaz 61357-43337Iran

Three diamine monomers with different derivatives of imidazole heterocyclic ring, aryl ethers and electron withdrawing trifluoromethyl groups in the backbone were synthesized and used in polycodensation reaction with various aliphatic and aromatic dicarboxylic acids for preparation of a series of novel polyamides （PAs）. The PAs were obtained in high yields and possessed inherent viscosities in the range of 0.26-0.75 dL/g. All of the polymers were amorphous in nature, showed outstanding solubility and could be easily dissolved in amide-type polar aprotic solvents. They showed good thermal stability with glass transition temperatures between 162-302 ℃. Thermogravimetric analysis showed that all polymers were stable, with 10% weight loss recorded above 421 ℃in N2 atmospheres. All the PAs presented fluorescence upon irradiation with ultraviolet light and thus showed promise for applications in electroluminescent devices. The monomers and PAs were also screened for antibacterial activity against Gram positive and Gram negative bacteria.

关键词： Photoactive polyamides Anthracene Fluorene Carbazole Antibacterial activity.

A QUICK AND GREEN IONIC LIQUID-MEDIATED APPROACH FOR THE SYNTHESIS OF HIGH-PERFORMANCE, ORGANOSOLUBLE AND THERMALLY STABLE POLYIMIDES

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Chinese Journal of Polymer Science 2013年第4期31卷 679-690页

作者： Mehdi taghavi Mousa Ghaemy Marjan Hassanzadeh seyed Mojtaba Amini Nasab Polymer Chemistry Research Laboratory Department of ChemistryUniversity of MazandaranBabolsar 47416-95447Iran

Three diamine monomers with different derivatives of imidazole heterocyclic ring and meta-linked aryl ethers were synthesized and used in polycodensation reaction with various commercial dianhydrides for preparation of a series of novel poly（ether-imide）（PEI）s. The polycodensation reactions were carried out by using conventional method and in a green medium of ionic liquid （IL） without using NMP-pyridine-acetic anhydride. The PEIs were obtained in good yields （80%-96%） with moderate viscosity （0.48-0.66 dL/g） in a shorter reaction time （10 h） in IL as compared with the conventional method （36 h）. All of the polymers were amorphous in nature, showed excellent solubility in amide-type polar aprotic solvents with ability to form tough and flexible films, and excellent thermal stability with Tgs in the range of 212-340℃ and 10% weight loss temperature （T10） up to 570℃ in N2 and 528 ℃ in air.

关键词： Ionic liquids Poly(ether-imide) Polycodensation Green media Thermal properties.

Successful interferon desensitization in a patient with chronic hepatitis C infection

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World Journal of Gastroenterology 2009年第33期15卷 4196-4198页

作者： seyed Alireza taghavi Ahad Eshraghian Gastroentero-hepatology Research Center of Shiraz University of Medical Science Nemazee Hospital

Treatment of hepatitis C, even when absolutely necessary, is almost impossible when interferon cannot be administered for any reason. We report a 65-year-old patient with chronic hepatitis C virus (HCV) infection and fibrosis, who was unable to receive interferon because of systemic hypersensitivity. The patient was desensitized successfully through gradual incremental exposure to interferon, and HCV infection was eradicated after a complete course of treatment, with no further allergic reactions. This case report that describes successful eradication of hepatitis C in a patient with advanced liver disease after desensitization to interferon revealed that desensitization may not necessarily damage the therapeutic efficacy of the drug.

关键词： Chronic hepatitis C Desensitization Drug hypersensitivity Interferon a2b Ribavirin

Zoning of Nitrite and Nitrate Concentration in Groundwater Using Geografic Information System (GIS), Case Study: Drinking Water Wells in Yazd City

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Journal of Geoscience and Environment Protection 2016年第3期4卷 91-96页

作者： reza Ali Fallahzadeh seyed Ali Almodaresi Mohamad Mehdi Dashti Ahmad Fattahi Mojtaba Sadeghnia Hadi Eslami Rasoul Khosravi Roya Peirovi Minaee Mahmoud taghavi Department of Environmental Health Engineering Faculty of Public Health Shahid Sadoughi University of Medical Sciences Yazd Iran Department of GIS & RS Engineering College Yazd Branch Islamic Azad University Yazd Iran Department of Occupational Health Engineering School of Public Health Shahid Sadoughi University of Medical Sciences Yazd Iran Department of Environmental Health Engineering Zabol University of Medical Sciences Zabol Iran

Studies have demonstrated that the presence of nitrate and nitrite in drinking water can cause some disease such as cancer and blu baby in the infant. The Environmental Protection Agency (EPA) has since adopted the 10 mg/L standard as the maximum contaminant level (MCL) for nitrate-nitrogen and 1 mg/L for nitrite-nitrogen for regulated public water systems. Given the importance of nitrate and nitrite in drinking water as well as GIS ability in spatial analysis of various factors in the groundwater, this study aimed to evaluate concentration of nitrate and nitrite in the drinking water wells of Yazd using two IDW (Inverse Distance Weighting) and Kriging models. In this descriptive study, the applied data on the water quality of underground water of Yazd Environmental Health Office and the average annual nitrate and nitrite in 2015 were related to 24 wells in the studied area. The nitrate and nitrite rate in groundwater in wells was compared to the standard amount of Institute of Standard and Industrial Researches and then was analyzed via Arc GIS software using IDW and Kriging interpolation methods. The mean concentration of nitrate was 17.62 ± 3.08 mg/l and for nitrite was 0.011 ± 0.003 mg/l in the wells. In the all studied zone, the nitrate and nitrite rate was in the standard range according to the National Standard of Iran (No. 1053). In this study, Kriging interpolation method was more efficient than IDW method.

关键词： Drinking Water Nitrite and Nitrate Concentration Geographic Information Systems Interpolation

Occult hepatitis B virus infection and cryptogenic chronic hepatitis in an area with intermediate prevalence of HBV infection

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World Journal of Gastroenterology 2006年第31期12卷 5048-5050页

作者： Mohammad Javad Kaviani Behzad Behbahani Mohammad Jafar Mosallaii Fatemeh Sari-Aslani seyed Alireza taghavi Gastroenterohepatology research centerDepartment of Internal medicine Namazee HospitalShiraz University of medical sciencesShirazIran Professor Abdolvahhab Alborzi's pediatric clinical microbiology research centerNamazee Hospital Shiraz University of medical sciencesShirazIran Department of pathologyShiraz University of medical sciences ShirazIran

AIM： To assess the possible role of occult HBV infection in the pathogenesis of chronic hepatitis in Iranian patients. METHODS： After exclusion of autoimmune, metabolic and viral etiologies, 104 consecutive adult patients with histologic and biochemical features of chronic hepatitis and negative HBsAg were enrolled in the study. Qualitative PCR with a sensitivity of 150 × 10^3 copies/L, using two primers for Pre-S and core regions was applied to measure presence of HBV DNA in serum of the patients. RESULTS： All 104 patients completed the study Qualitative HBV DNA was positive in two patients （1.9%） CONCLUSION： Occult HBV infection has negligible role in the pathogenesis of cryptogenic chronic hepatitis in Iranian patients.

关键词： Hepatitis B Cryptogenic chronic hepatitis PCR

Analysis of the glucokinase gene in Iranian families with maturity onset diabetes of the young

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Journal of Diabetes Mellitus 2013年第4期3卷 192-198页

作者： Meisam Javadi Houshang Rafatpanah seyed Morteza taghavi Jalil Tavakolafshari Rashin Ganjali Narges Valizadeh seyedeh Seddigheh Fatemi Bu-Ali Research Center Mashhad University of Medical Sciences Mashhad Iran Immunogenetics Department Immunology Research Center Bu-Ali Research Center Mashhad University of Medical Sciences Mashhad Iran Internal Medicine Department Ghaem Hospital and Endocrine Research Center Mashhad University of Medical Sciences Mashhad Iran Mashhad University of Medical Sciences Mashhad Iran

Non insulin dependent diabetes mellitus (NIDDM) as a most common form of diabetes is a major public health problem;there is a subgroup of NIDDM patients who develop the disease at an early age and show a dominant mode of inheritance. This type is nominates Maturity onset diabetes of the young (MODY). The prevalence of MODY is difficult to access, and patients with MODY genes mutations are often identified during routine screening for other purposes. MODY2 was linked to glucokinase gene (GCK) mutations, and accounted for 8% to 56% of MODY, with the highest prevalence found in the southern Europe. The aim of this study was to examine the prevalence and nature of mutations in GCK gene in Iranian paients. We have screened GCK mutations by polymerase chain reaction (PCR);single stranded conformation polymorphism (SSCP) technique in 12 Iranian families with clinical diagnosis of MODY, included 30 patients (8 males and 22 females) and their 21 family members. PCR products with abnormal mobility in denaturing gradient gel electrophoresis (DGGE) were directly sequenced. We identified 6 novel mutations in GCK gene in Iranian families (corresponding to 36.6% prevalence). Our findings and the last study on MODY1 highlight that in addition to GCK, other MODY genes such as MODY3 and MODYX may play a significant role in diabetes characterized by monogenic autosomal dominant transmission. There is an important point that the genetic recognation can be used to pre-symptomatically identify family members at risk for developing MODY.

关键词： Maturity Onset Diabetes of the Young 2 (MODY2) Glucokinase (GCK) Mutation SSCP PCR