Time filter

Source Type

Eslami R.,Allame Tabatabaee University | Sorkhkamanzadeh G.,Islamic Azad University at Kerman | Kazemi A.-R.,ValiAsr University of Rafsanjan | Gharakhanlou R.,University of Tehran | Banaifar A.-A.,Islamic Azad University at South Tehran
Journal of Mazandaran University of Medical Sciences

Background and purpose: Etiology of diabetic neuropathy is unclear, however, the accumulation of final products of glycation, vascular dysfunction, oxidative stress, and changes in neurotrophic support are considered as important factors in the genesis of this disease. The aim of this study was to investigate the effect of a 6-week endurance training program on gene expression of Brain Derived Neurotrophic Factor (BDNF) in the Sciatic nerve motor roots of rats with diabetic neuropathy. Materials and methods: Twenty eight adult male Wistar rats in the body mass range of 271±11.2 gr, were randomly assigned into four groups: diabetic control, diabetic training, healthy control, and healthy training. For inducing diabetic neuropathy, Streptozotocin (45 mg/kg, ip body wt.) was injected after twelve hours of food deprivation. Two weeks later, the endurance training protocol was performed for six weeks and 24hr after the last training session, the rats were sacrificed and spinal cords were processed for histological examination. Real-Time PCR was used for BDNF expression. For data Analysis, two-way ANOVA and LSD post hoc test were applied. Results: Data indicate that diabetes decreased BDNF expression in Sciatic nerve motor roots (P=0.05). However, 6 weeks of endurance training could partly compensate the BDNF expression decrease induced by diabetic neuropathy (P=0.05). However, this intervention could not return the BDNF expression level to that of the healthy control group (P=0.01). Conclusion: This study showed that diabetes can decrease BDNF expression in Sciatic nerve motor roots. But this decrease could somewhat be improved by endurance training. Our study supports the hypothesis that neurotrophic support decreases in diabetic neuropathy. © 2015, Mazandaran University of Medical Sciences. All rights reserved. Source

Mirzaei M.,ValiAsr University of Rafsanjan | Gishin M.J.,Kar Higher Education institute | Abbaspour M.,Shiraz University of Technology
Advanced Materials Research

In this study, the effect of solid-liquid volumetric ratio in laminar flow of nano-fluid has been investigated numerically. The conservation equations are utilized in three dimensional elliptical forms for laminar and steady flow, and the effects of adding aluminum oxide nano-particles to water based-fluid are studied. First, the influence of solid-liquid volumetric ratio on the secondary flow vortices, non-dimensional temperature is investigated for a flow with a fixed low Reynolds number and different Grashof numbers in a horizontal pipe. Then, the effect of variation in solid-liquid volumetric ratio on Nusselt number and convective heat transfer coefficient along the pipe is studied. The results of this study are in good agreement with the current literatures. © (2014) Trans Tech Publications, Switzerland. Source

Hajabdollahi H.,ValiAsr University of Rafsanjan | Ahmadi P.,University of Ontario Institute of Technology | Dincer I.,University of Ontario Institute of Technology
International Journal of Refrigeration

This paper presents a thermoeconomic optimization of a shell and tube condenser, based on two new optimization methods, namely genetic and particle swarm (PS) algorithms. The procedure is selected to find the optimal total cost including investment and operation cost of the condenser. Initial cost includes condenser surface area and operational cost includes pump output power to overcome the pressure loss. Design parameters are tube number, number of tube pass, inlet and outlet tube diameters, tube pitch ratio and tube arrangements (30, 45, 60 and 90°). Therefore, shell diameter should be selected less than 7 m, tube length should be less than 15 m, and ratio of diameter to tube length should be in the range of 1/12 to 1/3. In addition, it is found that GA provides better results for computer CPU running time, compared to PS algorithm. Finally, a sensitivity analysis of design parameters at the optimal point is conducted. Results show that an increase in the tube number leads to decrease in the objective function first then it leads to a considerable increment in objective function. © 2010 Elsevier Ltd and IIR. All rights reserved. Source

Farbod M.,Shahid Chamran University | Matin M.M.H.,ValiAsr University of Rafsanjan
Current Nanoscience

Carbon nanotubes (CNTs) were produced by arc method and effect of magnetic field on the purity of carbon nanotubes was investigated. In order to control arc discharging, a magnetic field was applied around the arc plasma. The samples were characterized by SEM, XRD and Raman spectroscopy measurements. The SEM images showed, the CNTs produced in the presence of magnetic field have much more purity and regularity than those produced in the absence of magnetic field. The results were confirmed by reduction of D Raman active mode intensity which is an indication of impurities in the CNTs. © 2011 Bentham Science Publishers. Source

4 3 2 1 11 10 9 8 7 6 5 18 17 16 15 14 13 12 25 24 23 22 21 20 19 31 30 29 28 27 26

Discover hidden collaborations