5 research outputs found
Investigation of Particles Statistics in large Eddy Simulated Turbulent Channel Flow using Generalized lattice Boltzmann Method
The interaction of spherical solid particles with turbulent eddies in a 3-D turbulent channel flow with friction Reynolds number was studied. A generalized lattice Boltzmann equation (GLBE) was used for computation of instantaneous turbulent flow field for which large eddy simulation (LES) was employed. The sub-grid-scale (SGS) turbulence effects were simulated through a shear-improved Smagorinsky model (SISM), which can predict turbulent near wall region without any wall function. Statistical properties of particles behavior such as root mean square (RMS) velocities were studied as a function of dimensionless particle relaxation time ( ) by using a Lagrangian approach. Combination of SISM in GLBE with particle tracking analysis in turbulent channel flow is novelty of the present work. Both GLBE and SISM solve the flow field equations locally. This is an advantage of this method and makes it easy implementing. Comparison of the present results with previous available data indicated that SISM in GLBE is a reliable method for simulation of turbulent flows which is a key point to predict particles behavior correctly
Optimization of Main Public Transport Paths Based on Accessibility — Case Study: Mashhad, Iran
Transport planning is an important aspect of urban planning. In this regard, enhancement of public transport systems and guiding urban travels towards them has found a crucial role in traffic improvement, preventing capital waste, and achieving sustainable cities. Mashhad, Iran, the second largest city in Iran, with a population of three million, has two main systems of public transport, light rail transit (LRT) and bus rapid transit (BRT). In designing these lines, not enough attention was paid to urban sustainability principles and maximizing access. The aim of this study was to redesign the main public transport lines using the approach of accessibility enhancement. The meta-heuristic method of Ant Colony Optimization was applied for this purpose. To compare the redesigned paths with the current paths, access indicators were defined and computed in the case of two alternatives. The results show that the access indicator in the modified alternative is significantly higher than the current one
Association between SGLT2 (sodium-glucose cotransporter-2) inhibitors and bladder cancer in individuals with type 2 diabetes; a systematic review and meta-analysis
Introduction: Sodium-glucose cotransporter-2 (SGLT2) inhibitors are the most recent pharmaceutical group for type 2 diabetes (T2D) treatment. Evidence indicates contradictory relationships between sodium-glucose cotransporter-2 inhibitors and bladder cancer (BC). Hence, this study aims to investigate the relationship between SGLT2 inhibitors and BC in patients with T2D. Materials and Methods: This study is a systematic review and meta-analysis based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). International databases including Cochrane, Web of Science, Scopus, PubMed, and Google Scholar were conducted for searching with keywords and without time and language limitations. The reference searching stage continued upgrading until November, 2022. Data analysis was performed with STATA 14 software. The tests with P values lower than 0.05 were considered statistically significant. Results: The four reviewed studies with a sample size comprising 497 755 individuals indicated the impact of SGLT2 inhibitors on BC of patients with T2D (OR: 0.68; 95% CI: 0.37, 1.2). The effect of dapagliflozin, canagliflozin and empagliflozin administration on the incidence of BC among the T2D patients were (OR: 0.72; 95% CI: 0.39, 1.30), (OR: 0.53; 95% CI: 0.23, 1.20), and (OR: 0.51; 95% CI: 0.20, 1.28), respectively. Conclusion: The general conclusion of this study revealed that SGLT2 inhibitors did not increase the risk of BC in T2D patients. The analysis of subgroups also indicated that the administration of dapagliflozin, canagliflozin, and empagliflozin also did not increase the risk of BC in T2D patients. Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO website (ID=CRD42023389014)