Particle deposition on the lung cell
Particulates inhaled by a human during normal breathing sometimes affect the lung cells. This project will develop a novel modelling framework capable of accurately representing the deposition zones and the slow clearance zone of the real bifurcation. The framework integrates models for CT Scans/MRI images, particles flow and mucus layer movement and accounts for particle deposition and clearance by multi-scale approach. It will provide a powerful tool to gain new insight and deepened understanding of the mechanisms of particle deposition and subsequent clearance through mucus movement. Therefore, it will significantly improve the drug delivery for asthma and cancer patients as well as other related diseases.
Modelling of Gold nanoparticle penetration into lung surfactant: Unravelling its mechanisms at the molecular scale
With the dawn of nanosciences, the use of nanomaterials has become widespread in various scientific fields from cosmetics and electronics to medicines and their increasing use has led to the release of nanoparticles (NPs) in the environment. While NPs featuring gold cores (AuNPs) have been in use for decades for targeted drug delivery of cancer drugs, one important problem is that exposure to AuNPs from the environment is a potential health hazard. The lungs are easily exposed to these particles present in the atmosphere, making contact with the inner surface of the alveolus called the lung surfactant (LS). LS monolayer which consists of lipids, four types of proteins and other molecules, is the first barrier that these NPs encounters in order to enter the circulatory system. Despite exhaustive experimental studies, the molecular-level mechanism behind the translocation and permeation of environmental and engineered AuNPs into the LS is still poorly understood. Coarse-grained (CG) molecular dynamics (MD) will be carried out to study a model pulmonary surfactant (PS) film interacting with AuNPs of different sizes, shapes and concentration. Additionally, similar simulations will be carried out in the presence of cholesterol and proteins SP-B and SP-C to investigate their effect on interactions with AuNPs at the air-water interface. A series of molecular-scale structural and dynamical properties of the surfactant film in the absence and presence of nanoparticle will be analysed, including phase behaviour, order parameter, pressure area isotherm, surface charge density, and area per lipid. Our preliminary results of CG system consisting DPPC: POPG lipids (7:3) and 3nm AuNPs show that AuNPs quickly interact with the lipid monolayer and create a rupture in the monolayer. The nano-bio interactions impede the surface activity of the surfactant system during the normal breathing process is in agreement with previously published experimental data. Our results will bring to the forefront the concern of the inhalation toxicity of AuNPs and their role in pulmonary disease. This PhD project will also provide guidelines for the future design of inhaled NPs with minimized side effects.
One of the key challenges for Australia lies in monitoring and managing rivers and estuaries effectively over large geographical areas. Traditionally, instrumentation at stationary points has been used for such monitoring, with the simplifying assumption that a single point adequately represents a very large region of water. This project will develop a novel moving (Lagrangian) drifter system Real-Time Flow Logging of Water (RT-FLOW) which takes flow and water quality measurements along the pathlines of the drifters over large regions of the waterway. The RT- FLOW system will directly enable stakeholders to better manage issues including storm surge, erosion, impacts of dredging and provide improved validation of hydrodynamic models.
Mucociliary Transport in Patients with Chronic Respiratory Diseases using an Advanced Numerical Method
Aerosols are solid or liquid particles suspended in air, which are naturally present in the form of dust, smoke, etc. From the toxicologic point of view, these particles have the potential of being biologically active in susceptible individuals. Therefore, it is vital to understand how these deposited particles are being cleared out of the respiratory system. Mucociliary clearance, the transport of foreign particles deposited on the lung airway surfaces by a blanket of mucus, is recognized as the principle as well as the fastest clearance mechanism in the trachea-bronchial region where the array
of cilia beat rapidly and propel the mucus, together with entrapped particulate materials (that might damage the lungs), from the airways towards the larynx. This research project aims to develop an advanced numerical model which can simulate the mucociliary clearance in a more realistic manner by considering a flexible structure for cilia beating on the lung epithelial cells and transporting airway surface liquid in normal functioning and disease.
Advances in real-time satellite monitoring of flow in rivers and estuaries (ARC Linkage Project)
A new biomechanical model for understanding aging of stored Red Blood Cells (ARC Linkage Project)
Stored red blood cells (RBCs) suffer aging-related deformability changes, which will impede RBC functions. This project will develop a novel modelling framework capable of accurately representing the biomechanical properties of RBCs overtime under stored conditions. The framework integrates models for RBC membrane, inside haemoglobin and outside storage solution, and accounts for aging effects by embedding time-dependent correlations. It will provide a powerful tool to gain new insight and deepened understanding of the mechanisms of deformability changes of RBCs during the stored lifespan. Therefore, it will significantly improve blood storage industry practices in terms of improving RBC storage protocols with preventative aging strategies.
Deformation of RBC in the capillary network
A healthy red blood cell (RBC) presents a good mechanical deformation property. The change of the mechanical property of RBC will lead to serious diseases. Hence, it is critical to understand the deformation mechanism of RBC. This project aims to thoroughly investigate the mechanical deformation properties of red blood cells into the capillary network. A novel meshfree particle model will be proposed for the purpose. This project will increase the knowledge and understanding of the deformation mechanics of red blood cells as a result of several key factors including environment, aging, and infection. The output obtained from this project will help in-depth understanding not only of prevention of cell infection and red blood cell-related diseases but also of the aging issues of RBC.
Heat transfer in attic space
This project deals with the numerical simulations of fluid flow and heat transfer inside an attic space for both hot and cold climate or day and night weather conditions. Different shapes of the attic space for both 2D and 3D will be investigated. Enhancement or suppression of heat transfer will be modelled by altering the geometry or putting several fins or partitions inside the enclosure. Ambient wind flow also affects the heat transfer through the inclined walls of the attic space.
© Copyright – Dr. Suvash C. Saha