The turbulent mixing of a two-dimensional jet of foreign gas with a moving air stream

Imperial Users onl

Computational fluid dynamic characterization of carotid bifurcation stenosis in patient-based geometries

Hemodynamic forces play a role in determining endothelial cell (EC) phenotype and influence vascular remodeling. We present a lesion-based computational fluid dynamic (CFD) pilot analysis to understand the complex spatial and temporal hemodynamic changes that prevail in patients with high-grade carotid artery stenosis (CS). High-resolution three-dimensional (3D) rotational angiography datasets were acquired in eight patients, and used to generate computational meshes. CFD analysis was carried out implementing realistic shear-dependent viscosity for blood. The mean wall shear stress (WSS) within the stenosis region was 107 ± 73 dyn/cm2 rapidly followed by direction reversal and lower oscillating values in the recirculation zone at a mean of 19 ± 14 dyn/cm2. WSS vectors exhibited complex dynamic directional and amplitude oscillations not seen in healthy segments, along with time-dependent convergence and divergence strips during the cardiac cycle. The spatial gradient of WSS revealed an elevated average magnitude at the throat of the stenosis of 1425 ± 1012 dyn/cm3. In conclusion, patient-based CFD analysis of CS predicts a complex hemodynamic environment with large spatial WSS variations that occur very rapidly over short distances. Our results improve estimates of the flow changes and forces at the vessel wall in CS and the link between hemodynamic changes and stenosis pathophysiology

Functional and molecular characterization of the vascular endothelial response to fluid shear stress

Thesis (Ph. D.)--Massachusetts Institute of Technology, Whitaker College of Health Sciences and Technology, 1994.Four reprints in pocket following text.Includes bibliographical references (leaves 217-236).by Adel Moussa Malek.Ph.D

The Role Of Leadership Styles On Staffs Job Satisfaction In Public Organizations

 Job satisfaction is a very important factor among the employees of Public Universities. Job satisfaction is considered an internal principle created by various elements found within a work environment. Due to the influence of various items on job satisfaction, educational organizations should be conscious of implementing the right leadership styles. However, the lack of attention given to this organizational behavior has led to the rise of abnormal reactions among employees. Thus, the current paper focused on the essential role of leadership styles in improving job satisfaction among the employees of Public Universities. Substantial attention should be dedicated to the precise leadership style practiced in an organization. In the same way, specific leadership styles, as external factors, have an important impact on the job satisfaction of employees at Public Universities, because these styles can improve the employees' commitment to the organizations. This initiative involves enhancing satisfaction among employees and finding an effective leadership style, which is one of the main components of improving educational organizations

O inferno em Eneida: mito e poesia

O presente artigo objetiva apresentar uma análise gradual da construção do mito do Inferno, através de elementos poéticos e míticos que se convertem em uma perspectiva imagética. No decorrer do artigo foi possível averiguar a complexidade em torno da criação mítica do Inferno, assim como os vários aspectos referentes a poeticidade que os mitos proporcionaram durante a construção do Mito Inferno, na obra Eneida. Assim, este estudo pode ser visto como um estudo complexo de mitos que interagem entre si, formando um mito maior mediante a poeticidade destes engendramentos: o Mito e a Poesia, na peregrinação de Enéias ao Reino dos Mortos