报告人：Dr Suvash Saha
题目及摘要：Particulates Matter Transport, Deposition, Interaction with Lung Surfactant, and Mucociliary Clearance in Realistic CT-Based Lung Airways
To understand how to assess optimally the risks of inhaled particles on respiratory health, it is necessary to comprehend the uptake of particulates matter by inhalation and exhalation during the complex transport process through a non-dichotomously bifurcating network of conduit airways. The highly toxic ultrafine particles damage the respiratory epithelium in the terminal bronchioles. The wide range of in silico available and the limited realistic model for the extrathoracic region of the lung have improved understanding of the particulates matter transport and deposition (TD) in the upper airways. However, comprehensive, particulates TD, interaction with the surfactant monolayer and mucociliary clearance data for the real and entire lung model are still lacking. Therefore, this study is aimed at providing an understanding of the particulates matter TD, interaction with lung surfactant, and mucociliary clearance in the terminal bronchioles for the development of future therapeutics. The Euler-Lagrange (E-L) approach, Molecular Dynamics (MD) approach and Lattice Boltzman Method (LBM) with Immersed Boundary Method (IBM) were used to investigate particulates transportation and deposition, surfactant layer interaction and mucociliary clearance respectively. The physical conditions of sleeping, resting, and light activity were considered in particle TD. A comprehensive pressure-drop along five selected path lines in different lobes was calculated. The non-linear behaviour of pressure-drops is observed, which could aid the health risk assessment system for patients with respiratory diseases. Numerical results illustrates that the micro-particle DE in the right lung is significantly higher than in the left lung during different breathing patterns. For polydisperse particle, the larger the particle diameter is (dp>5μm), the higher the DE at the bifurcation area of the upper airways, whereas for the smaller diameter particle (dp<5μm), the DE is higher at the bifurcation wall. Numerical results also showed that ultrafine particle-deposition efficiency (DE) in different lobes is unlike conditions for various physical activities. Moreover, the numerical results showed hot spots in various locations among the different lobes for different flow rates, which could be helpful for targeted therapeutical aerosol transport to terminal bronchioles and the alveolar region.
Dr. Suvash C. Saha is working at QUT as a Postdoctoral Research Fellow since 2011. His current research interests are: Computational biomechanical engineering, Solar thermal energy technology, Natural convection heat transfer in buildings and other confined geometries, Scale analysis for the transient flow etc. He received his PhD in Computational Fluid Dynamics from the School of Engineering and Physical Sciences of James Cook University in 2009. He received his BSc in Mathematics and MSc in Applied Mathematics with thesis group from the Department of Mathematics, University of Dhaka, Bangladesh. After obtaining his degree, Dr. Saha joined at IBAIS University, Bangladesh as a lecturer of Mathematics. He has more than 100 publications including more than 70 journal papers, 6 book chapters and 40 conference papers.