Minia University

About: Minia University is a education organization based out in Minya, Egypt. It is known for research contribution in the topics: Population & Medicine. The organization has 4967 authors who have published 8986 publications receiving 108384 citations.

Simulation of global MPPT based on teaching–learning-based optimization technique for partially shaded PV system

Abstract: The power against voltage curve for PV power system during shadow condition contains number of local maximum power points (MPPs) and only one global. The classical maximum power point tracking (MPPT) algorithms are designed to follow the global MPP, but they stuck around local MPPs such as fuzzy logic controller (FLC). Therefore, A global MPPT based on teaching–learning-based optimization (TLBO) algorithm has been presented in this paper. The performance of PV system under abnormal conditions such as partial shading has been improved. TLBO algorithm is simple computational steps and faster convergence to optimal solution. A comprehensive assessment of TLBO-based tracker is carried out against FLC and particle swarm optimization (PSO) techniques for same conditions. Six different partial shading patterns have been employed to investigate TLBO performance using MATLAB/Simulink. The parameters of comparison include the tracking speed and overall tracking efficiency. The results confirm that TLBO-based tracker exactly convergence to global MPP under different studied cases. TLBO has best performance compared to the other studied techniques. The tracking speed is increased using TLBO-based tracker; the average tracking time of global MPP is reduced by more than 23.8 % compared with PSO in all studied different partial shading patterns.

Effect of exposure and withdrawal of 900-MHz-electromagnetic waves on brain, kidney and liver oxidative stress and some biochemical parameters in male rats.

Abstract: Increasing use of mobile phones in daily life with increasing adverse effects of electromagnetic radiation (EMR), emitted from mobile on some physiological processes, cause many concerns about thei...

Nickel nanoparticles-decorated graphene as highly effective and stable electrocatalyst for urea electrooxidation

Abstract: Among the various carbonaceous materials, graphene is highly considered to provide the optimum support for the electrocatalytic materials due to its excellent electrical conductivity and extremely large surface area. In literature, based on our best knowledge, few studies have been reported to introduce effective electrocatalysts for urea oxidation. In this study, Ni-decorated graphene sheets are introduced as effective and stable electrocatalyst for urea oxidation. The introduced composite was prepared by reflux of graphene oxide with nickel acetate at 120 °C for 10 h followed by calcination in argon atmosphere at 850 °C for 2 h. X-ray diffractometer (XRD), transmission electron microscope (TEM) and Raman spectroscopy techniques confirmed formation of graphene sheets decorated by nickel nanoparticles. The synthesized Ni-decorate graphene shows distinct electrocatalytic activity toward urea oxidation. Numerically, using 2 M urea solution (in 1 M KOH) the corresponding current density was 150 mAcm −2 (2100 mAcm −2 g −1 ) with clear urea oxidation peaks in the forward and reverse scans. Study the influence of metal loading indicated that the amount of nickel nanoparticles should be optimized as the best performance has been observed when equal amounts of nickel acetate and graphene oxides were utilized during the preparation process. The introduced decorated graphene reveals good stability at various applied voltages. Overall, the study emphasizes the advantage of using graphene as support to distinctly enhancing urea electrooxidation.

Molecular characterization of the grape seeds extract's effect against chemically induced liver cancer: In vivo and in vitro analyses.

Abstract: The purpose of this study was to investigate the anti-cancer property of grape seed extract (GSE) during early stages of developing liver cancer using a two-stage carcinogenic model combining diethylnitrosamine (DEN) and 2-Acetyl Aminofluorene (2-AAF). Administration of GSE at doses 25, 50 and 100 mg/kg per day started at the beginning of promotion periods and continued for 14 weeks. GSE dramatically inhibited pre-neoplastic foci formation as well as significantly decreased the number and the area of placental glutathione-S-transferase in livers of DEN-2AAF-treated rats by approximately 4 & 10 fold deductions, respectively. GSE’s effects were associated with induced apoptosis, reduced cell proliferation, decreased oxidative stress and down regulation of histone deacetylase activity and inflammation makers, such as cyclooxygenase 2, inducible nitric oxide synthase, nuclear factor-kappa B-p65 and p- phosphorylated tumor necrosis factor receptor expressions in liver. GSE treatment also decreased the viability of HepG2 cells and induced early and late apoptosis through activating caspase-3 and Bax. Furthermore, GSE induced G2/M and G1/S cell cycle arrest. The present study provides evidence that the GSE’s anticancer effect is mediated through the inhibition of cell proliferation, induction of apoptosis, modulating oxidative damage and suppressing inflammatory response.