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Background: Carotid angioplasty and stenting (CAS) is an accepted treatment to prevent stroke in patients with carotid artery stenosis. The purpose of this study is to identify risk factors for major complications after carotid angioplasty and stenting.Methods and Material: This is a prospective study conducted at Shiraz University of Medical Sciences in southern Iran from March 2011 to June 2014. Consecutive patients undergoing carotid angioplasty and stenting were enrolled. Both standard risk and high risk patients for endarterectomy were enrolled. Demographic data, atherosclerotic risk factors, site of stenosis, degree of stenosis, and data regarding technical factors were recorded. 30-day stroke, myocardial infarction, and/or death were considered as the composite primary outcome of the study.Results: two hundred and fifty one patients were recruited (mean age: 71.1+ 9.6 years, male: 65.3%). One hundred and seventy eight (70.9%) patients were symptomatic; 73 (29.1%), 129 (51.4%), 165 (65.7%) and 62 (24.7%) patients were diabetic, hyperlipidemic, hypertensive and smoker respectively. CAS performed for left ICA in 113 (45.4%) patients. 14 (5.6%) patients had Sequential bilateral stenting. Mean stenosis of operated ICA was 80.2 +13.8 %. Embolic protection device was used in 203 (96.2%) patients. Predilation and post-dilation were performed in 39 (18.5%) and 182 (86.3%) patients respectively. Composite outcome was observed in 3.6% (3.2% stroke, 0% myocardial infarction and 1.2% death). Left sided lesions and presence of DM was significantly associated with poor short term outcome. (P value: 0.025 and 0.020, respectively)Conclusion: There was a higher risk of short term major complications in diabetic patients and left carotid artery intervention.

It is well known that injection strategies including the injection timing and pressure play the most important role in determining engine performance, especially in pollutant emissions. However, the injection timing and pressure quantitatively affect the performance of diesel engine with a turbo charger are not well understood. In this paper, the fire computational fluid dynamics (CFD) code with an improved spray model has been used to simulate the spray and combustion processes of diesel with early and late injection timings and six different injection pressure (from 275 bar to 1000 bar). It has been concluded that the use of early injection provides lower soot and higher NO x emissions than the late injection. In this study, it has been tried using the change of fuel injection time at these two next steps: before top dead center (BTDC) and after top dead center (ATDC) in order to achieving optimum emission and power in a specific point.

In this study, maintaining a constant fuel rate, injection pressure of 275 bar to 1000 bar (275×10 2 kPa to 1000×10 2 kPa), has been changed. Effect of injection pressure, the pressure inside the cylinder on the free energy, power, engine indicators, particularly indicators of fuel consumption, pollutants and their effects on parameters affecting the output of the engine combustion chamber have been studied in droplet diameter. Finally, the effects of fuel mixture equivalence, Cantor temperature, soot and NO x due to the increase of injection pressure, engine efficiency and emissions have been examined.

Background: Carotid angioplasty and stenting (CAS) is an accepted treatment to prevent stroke in patients with carotid artery stenosis. The purpose of this study is to identify risk factors for major complications after CAS. Materials and Methods: This is a prospective study that was conducted at Shiraz University of Medical Sciences in southern Iran from March 2011 to June 2014. Consecutive patients undergoing CAS were enrolled. Both standard- and high-risk patients for endarterectomy were enrolled. Demographic data, atherosclerotic risk factors, site of stenosis, degree of stenosis, and data regarding technical factors were recorded. Thirty-day stroke, myocardial infarction, and/or death were considered as the composite primary outcomes of the study. Results: A total of 251 patients were recruited (mean age: 71.1 ± 9.6 years; male: 65.3%). Of these, 178 (70.9%) were symptomatic, 73 (29.1%) were diabetic, 129 (51.4%) were hyperlipidemic, 165 (65.7%) were hypertensive, and 62 (24.7%) patients were smokers. CAS was performed for left internal carotid artery (ICA) in 113 (45.4%) patients. Fourteen (5.6%) patients had sequential bilateral stenting. Mean stenosis of operated ICA was 80.2 ± 13.8%. An embolic protection device was used in 203 (96.2%) patients. Pre- and postdilation were performed in 39 (18.5%) and 182 (86.3%) patients, respectively. Composite outcomes were observed in 3.6% of patients (3.2% stroke, 0% myocardial infarction, and 1.2% death). Left-sided lesions and the presence of diabetes mellitus were significantly associated with poor short-term outcome (p = 0.025 and p = 0.020, respectively). Conclusion: There was a higher risk of short-term major complications in diabetic patients and for left carotid artery intervention.

Slab method of analysis has been used for solving metal forming problems for a long time. However it has been restricted to plane strain and axisymmetric problems due to limitations in its formulations. In this paper a new formulation has been proposed so that it could be applied to three dimensional problems in metal forming. A parametric slab has been considered in this analysis and the force balance on the slab was carried out to obtain equilibrium equations in terms of these parameters. The parameters in fact are related to the geometry of the final extruded shape, the die and the material flow regime assumed in the formulation. In this way most of the limitations encountered in previous formulations were surpassed. In fact the parametric slab considered in this formulation is a very general element that could be adjusted to any changes made in the process. As an example the forward extrusion of a square cross section was analyzed using the new formulation. The effect of reduction of area, frictional conditions and other process parameters on the extrusion pressure was investigated. The theoretical results obtained in this paper were compared with similar results of previous work from other methods and good agreement was observed. Dies were designed and manufactured based on this analysis for several reductions of area. Tests were done using above dies and the experimental data were found to verify the theoretical results. It was concluded that the new slab method of analysis gave reasonable results for the problem analyzed and that it could be applied to other bulk metal forming processes such as rolling, wire drawing and forging.Copyright © 2010 by ASME