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Antimicrobial susceptibility of helicobacter pylori strains isolated from patients in Shiraz, Southern Iran

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World Journal of Gastroenterology 2010年第45期16卷 5746-5751页

作者： Shohreh Farshad Abdolvahab Alborzi Aziz Japoni Reza Ranjbar Kazem hosseini Asl Parisa Badiee Maneli Amin Shahidi Marziyeh.hosseini Professor Alborzi Clinical Microbiology Research Centre Shiraz University of Medical SciencesShiraz 71937-11351Iran Molecular Biology Research Center Baqiyatallah University of Medical SciencesTehran 19945-581Iran Gastroenterohepatology Research Center Shiraz University of Medical SciencesNemazee HospitalShiraz 71345-1414Iran

AIM: To improve our understanding of Iranian regional variation in helicobacter pylori (h. pylori ) antibiotic resistance rates to find the best antibiotic therapy for eradication of h. pylori ***: A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. h. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of h. pylori isolates was determined by ***: A total of 121 h. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P he metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/***: We found a moderate rate of primary resistance to metronidazole. however, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the h. pylori strains in our region.

关键词： Gastric disorders helicobacter pylori Iran Sensitivity Treatment

Electrostatic Enhancement of Coalescence of Oil Droplets(in Nanometer Scale) in Water Emulsion

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Chinese Journal of Chemical Engineering 2012年第4期20卷 654-658页

作者： hosseini M. ShAhAVI M.h. Faculty of Chemical Engineering Babol Noshirvani University of TechnologyBabolIran

Oil droplets in nanometer scale which are dispersed in water cannot be separated easily. An attractive technique is carried out by electrical phenomena to demulsify oil in water emulsion. In this research, non-uniform electric field or dielectrophoresis （DEP） is applied to remove sunflower oil （which is dispersed in the water）. Effectsof temperature, time and voltage （using AC-electric field） were considered to get the highest DEP-force （Fdi） and the best results. The oil particles sizes with average of approximately 76 nm have been shown using a ZetaSizer Nano ZS, Model ZEN 1600 （Malvem Instrument Ltd.）. The maximum separation efficiency of 85% is obtained at the optimum temperature of 38 ℃ and voltage of 3000 V.

关键词： demulsification oil/water emuision electric field dielectrophoresis

Effects of Pits and Mounds Following Windthrow Events on Soil Features and Greenhouse Gas Fluxes in a Temperate Forest

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Pedosphere 2015年第6期25卷 853-867页

作者： Yahya KOOCh Sakineh Mollaei DARABI Seyed Mohsen hosseini Department of Forestry Faculty of Natural Resources & Marine SciencesTarbiat Modares University

Pit and mound micro-relief(resultant microsites from trees uprooted by windthrow) could have regimes of microclimate and soil features that differ from areas of undisturbed soil. In an attempt to provide a comprehensive evaluation of the significance of pits and mounds on soil features and also the dynamics of greenhouse gas(GhG) fluxes at local scale, this study was carried out in a reserved area of Darabkola forest in Mazandaran Province, northern Iran. The age of a pit and mound was considered equal to the degree of decay of the blown down tree. Three microsites were distinguished, consisting of pit bottom(PB), mound top(MT) and undisturbed area(UA). Soil samples were taken at 0–15 and 15–30 cm depths from all microsites and analysed for soil physical, chemical and biological features. Our findings suggested that in context of forest ecology, pits and mounds following windthrow events should be considered as an effective factor influencing soil features(i.e., density, texture, water content, p h, organic C, total N, available nutrients and earthworm density/biomass) and especially GhG fluxes. Results showed that MT acted as a sink for N2O(-0.010 mg N2 O m-2d-1) and Ch4(-0.257 mg Ch4m-2d-1) fluxes and also produced lower CO2 concentrations(0.095 mg CO2 m-2d-1) than PB(0.207 mg CO2 m-2d-1) and UA(0.098 mg CO2 m-2d-1). As a consequence, a separation into pits/mounds would be important for a precise budgeting of greenhouse gases.

关键词： carbon dioxide, methane microsite, nitrous oxide oriental beech, uprooted tree

Mechanisms of joint formation throughout semisolid stir welding of AZ91 magnesium alloy

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Transactions of Nonferrous Metals Society of China 2013年第9期23卷 2585-2590页

作者： V. A. hosseini h. AAShURI A. KOKABI Materials Science and Engineering Department Sharif University of Technology

Joining in the semisolid state is considered a possible method to join alloys to each other. The mechanisms taking part in semisolid stir welding of AZ91 alloys were investigated. Two 7.5 mm-thick AZ91 pieces and a 2 ram-thick Mg-25%Zn interlayer piece were placed in a heating plate. After holding for 3 min at a desired temperature, the weld seam was stirred by a rotational tool. The heating plate was travelled on a trolley at a constant speed of 4.6 cm/min. In addition, one sample was welded without interlayer. Evolution of welding as a function of stirring rate, tool shape and temperature was studied throughout this welding process with scanning electron and optical microscopes. Interlayer decreases the joining temperature and assists to investigate the possible semisolid stir welding mechanisms. Increasing temperature and stirring rate, and using round stirrer instead of grooved stirrer increase the stir zone width. The results show that some possible mechanisms are helpful to achieve a proper metallurgical bonding in the welding process, such as oxide layer disruption, liquid phase blending, globule joining, and liquid penetration to the base metal, merging a group of globule into stir zone from the base metal.

关键词： AZ91 magnesium alloy semisolid joining Mg-Zn interlayer mechanical stirring metallurgical bonding

Controlled temperature-mediated curcumin release from magneto-thermal nanocarriers to kill bone tumors

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Bioactive Materials 2022年第5期7卷 107-117页

作者： A.Khodaei F.Jahanmard h.R.Madaah.hosseini R.Bagheri A.Dabbagh h.Weinans Amin Yavari Institute for nanoscience and nanotechnology sharif university of technologytehraniran department of orthopedics university medical center utrechtutrechtthe netherlands department of materials science and engineering sharif university of technologytehraniran school of medicine faculty of health and medical sciencestaylor’s universitysubang jayamalaysia regenerative medicine utrecht utrecht universityutrechtthe netherlands

Systemic chemotherapy has lost its position to treat cancer over the past years mainly due to drug resistance,side effects,and limited survival *** a plethora of local drug delivery systems to solve this issue,the combinatorial strategy of chemo-hyperthermia has recently received *** we developed a magneto-thermal nanocarrier consisted of superparamagnetic iron oxide nanoparticles(SPIONs)coated by a blend formulation of a three-block copolymer Pluronic F127 and F68 on the oleic acid(OA)in which Curcumin as a natural and chemical anti-cancer agent was *** subsequent nanocarrier SPION@OA-F127/F68-Cur was designed with a controlled gelation temperature of the shell,which could consequently control the release of *** release was systematically studied as a function of temperature and ph,via response surface methodology(RSM).The bone tumor killing efficacy of the released curcumin from the carrier in combination with the hyperthermia was studied on MG-63 osteosarcoma cells through Alamar blue assay,live-dead staining and apoptosis caspase 3/7 activation *** was found that the shrinkage of the F127/F68 layer stimulated by elevated temperature in an alternative magnetic field caused the curcumin *** the maximum release concentration and cell death took place at 45℃,treatment at 41℃ was chosen as the optimum condition due to considerable cell apoptosis and lower side effects of mild *** cell metabolic activity results confirmed the synergistic effects of curcumin and hyperthermia in killing MG-63 osteosarcoma cells.

关键词： Osteosarcoma Magnetic hyperthermia Curcumin MRI contrast agent

Investigation of salinity impacts on germination and growth of two forest tree species at seedling stage

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Journal of Forestry Research 2013年第4期24卷 703-708页

作者： Seyed Mohammad hosseini Nasr Sekineh Kiani Savadkoohi Elahe Ahmadi Department of Forestry Sari Agricultural Sciences and Natural Resources University

Soil salinity is becoming an increasingly serious constraint to plant growth in many parts of the world; this is particularly common in semi-arid and arid zones. This study was conducted to evaluate the effect of different concentrations of salt on seed germination and seedling growth of Acacia albida and A. salicina. Collected seeds were treated with h2SO4 98% for 35 min then left to germinate in a controlled growth chamber. Seeds were grown at salinity levels of 0.1, 0.2 and 0.3 mol.L1 of Nah2PO4.h20. Germination parameters and seedling growth indices were measured after 35 days. The mean of total length ofA. salicina in all salinity concentrations was more than that of ：4. albida. The fresh weight of stem and root of ：4, albida was more than that of ：4. salicina. Growth of control seedlings was higher than for other treatments and the fresh weight of stems of two species at salt concentrations of 0.2 and 0,3 *** decreased with increasing concentration of salt. Most Control seeds germinated at salinity of 0.1 *** and germination index, final germination and seeds stamina was greater at low levels of salinity.

关键词： soil salinity germination salt concentration Acacia albida,Acacia salicina.

EIS Study on Pitting Corrosion of AA5083-h321 Aluminum-Magnesium Alloy in Stagnant 3.5% NaCl Solution

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Journal of Materials Science & Technology 2008年第2期24卷 215-219页

作者： K.Jafarzadeh T.Shahrabi M.G.hosseini Corrosion Lab. Materials Eng.Dept.Tarbiat Modares Univ.TehranIran Dept.of Physical Chemistry Facul-ty of ChemistryTabriz Univ.TabrizIran

In this research, EIS （electrochemical impedance spectroscopy） technique was utilized to study the pitting corrosion behaviour of AA5083-h321 aluminum-magnesium alloy in 3.5% NaCl solution. Impedance spectra were obtained during 240 h of exposure of the sample to the test solution. The surface and cross-section of the samples were studied by scanning electron microscopy （SEM） and EDAX （energy dispersive analysis of X-ray） analysis. The results indicated that as the resistance of the passive layer on intermetallic particles is very small, this parameter on the sample surface layers is controlled by that of pure passive layer. however, the capacitors in the proposed equivalent circuit are replaced with the constant phase elements （CPE）, due to non-uniformity and occurrence of pitting corrosion on the surface. The outward diffusion of Al^＋3 ions through the passive layer and the thickening of this layer cause the impedance decrease in the first 24 h and increase afterwards. The detachment of intermetallic particles from some of pits and the accumulation of the corrosion products inside some others are factors that prevents the continuation of cathodic reactions on the top of the intermetallic particles.

关键词： Corrosion AA5083-h321 aluminum-magnesium alloy Impedance Pitting Intermetallic particle Passive layer

基于多阶人工神经网络的ECG信号诊断模型研究

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仪器仪表学报 2008年第1期29卷 27-32页

作者：骆德汉许广桂邹宇华 h.Gholam hosseini 广东工业大学中国广州510006 奥克兰工业大学工程学院新西兰奥克兰1142

目前已经有多种不同的ECG(心电图)信号辅助诊断工具得到应用,其中包含了基于人工神经网络的ECG分类器应用系统。本文介绍一种基于多阶前馈人工神经网络的新型ECG信号诊断模型,其目标是设计一种结构简单、成本低、响应速度快,识别率高的... 详细信息

目前已经有多种不同的ECG(心电图)信号辅助诊断工具得到应用,其中包含了基于人工神经网络的ECG分类器应用系统。本文介绍一种基于多阶前馈人工神经网络的新型ECG信号诊断模型,其目标是设计一种结构简单、成本低、响应速度快,识别率高的ECG信号辅助诊断系统。首先给出多个不同结构的神经网络,然后针对6种不同的心脏状况,比较这些神经网络之间的性能差异和辨别能力。网络的输入数据来自于M IT/B Ih数据库,包括12种ECG特征信号和相应的每次心脏搏动的13段压缩信号。通过研究测试发现,基于二阶神经网络的ECG模型识别率最高,正确率达到了90.57%。

关键词： ECG信号分类器人工神经网络(ANN) ECG信号诊断多阶前馈神经网络

Experimental and numerical assessment of energy absorption capacity of thin-walled Al 5083 tube produced by PTCAP process

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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1238-1248页

作者： A.hosseini D.RAhMATABADI R.hAShEMI h.AKBARI School of Mechanical Engineering Iran University of Science and TechnologyTehranIran

The energy absorption capacity of the Al5083 thin-walled tube produced by parallel tubular angular pressing(PTCAP) process was evaluated. Also, microstructure, mechanical properties, and anisotropy coefficients were studied in the peripheral and axial directions. Results showed that values of energy absorption decreased with processing pass increasing and the values for the unprocessed, first and second passes were obtained to be 167, 161.4 and 160.7 J, respectively. The differences between the simulation results for the energy absorption values and their experimental values for the unprocessed, the first and the second PTCAP passes samples are about 5%, 10%, and 13%, respectively. The energy absorption capacity was related to the anisotropy coefficient and microstructure. The results demonstrated that grain refinement occurred and ultimate tensile strength(UTS) and microhardness after the first and second PTCAP passes were enhanced, while the increase rate in the first pass was much severer. Also, by applying PTCAP, the deformation modes were altered, such that the deformation mode of the annealed tube was quite symmetrical and circular while for the first and second passes there have been triple and double lobes diamond. The results of the numerical simulation for the deformation mode of the annealed and PTCAPed tubes were consistent with the experimental results. The deformation mode of tubes is dependent on their mechanical properties and variation of the mechanical properties during PTCAP process.

关键词： energy absorption Al 5083 ultra-fine grained aluminum alloy thin-walled tube severe plastic deformation anisotropy coefficient