mohamadjavad ebrahimi

The study and investigation of the currents passing through non-concentric annular cylinders is of great importance due to its application in many fields such as oil and petrochemical industries. Oil well drilling is an example of this application. In the current research, non-Newtonian fluid is considered between two non-concentric cylinders rotating. The changes in the speed of the rotating cylinder and as a result the changes in the radial speed, axial speed, and tangential speed of the fluids were investigated along the selected planes. Turbulence kinetic energy and shear stress on the cylinder walls, which are effective factors in fluid flow, were also analyzed and investigated. Also, in this research, a study was conducted on several non-Newtonian fluids, such as bentonite, carboxyl methyl cellulose, and xanthan gum dissolved in water, in comparison with water. Two fluids, XG and CMC, had the most similarities with the rheological properties of water, while the XG fluid kept its rheological properties at high speeds. The simulations were compared with the experimental results available in the literature, and a good agreement was observed between the results..

Background and Acute kidney failure is one of the major problems around the world. It increases the rate of morbidity and mortality, and also leads to increased hospitalization time and health care costs. This study aimed at investigating the prevalence of acute kidney failure following coronary artery bypass grafting (CABG).
In a descriptive study, 400 medical records of CABG cases in Mazandaran Herat Center (2013-2016) were studied using random sampling. Creatinine levels of 24 hours before and after the surgery were recorded in a checklist. Data were analyzed in SPSS V20 applying Logistic Regression Analysis.
The patients studied included 59% males and 41% females. The mean age of patients was 61±9.05 years. The prevalence of acute renal failure was 13.5% following CABG. Based on univariate regression, gender (OR = 5.71, P In this study, age, sex, smoking, BUN levels and BMI were associated with the incidence of acute kidney failure after CABG.