Preethi Gopalan

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Neutrophil emigration through endothelial cells under shear flow involves several adhesion processes including cell rolling, arrest, and transmigration. Rolling is mediated by selectins, while arrest and transmigration both require activated CD18 integrins. One mode of CD18 activation is via selectins expressed on neutrophils and endothelial cells. We have(More)
Ex situ experiments were conducted to study water droplet dynamics in Proton Exchange Membrane Fuel Cell (PEMFC) gas channels with different trapezoid channel open angles and GDL materials under controlled air velocities (0.48e7.23 m s 1). High speed videos revealed that the droplets interacted with the channel walls at lower air velocities (0.48e4 m s 1)(More)
Emigration of leukocytes at sites of inflammation is initiated by the selectin family of carbohydrate-binding adhesion molecules. Molecular crossbridges initiate rolling of cells along the vascular endothelium where chemokines such as IL-8 and platelet activating factor (PAF) may be presented to their receptors on the leukocyte surface resulting in cell(More)
E-selectin is an inducible cell adhesion molecule which mediates rolling of neutrophils on the endothelium, an early event in the development of an inflammatory response. Inhibition of selectin-mediated rolling is a possible means for controlling inflammation-induced diseases, and several classes of compounds have been tested for this use. We describe here(More)
Understanding the effect of two-phase flow in the components of proton exchange membrane fuel cells (PEMFCs) is crucial to water management and subsequently to their performance. The local water saturation in the gas diffusion layer (GDL) and reactant channels influences the hydration of the membrane which has a direct effect on the PEMFC performance. Mass(More)
Water appears as a byproduct during normal operation of Proton Exchange Membrane Fuel Cell (PEMFC), and stagnates on the gas diffusion layer (GDL) affecting its performance under certain operating conditions. The primary goal of this study was to develop an ex-situ experimental setup to analyze the sidewall interactions and droplet dynamics under controlled(More)
Neutrophils form CD18-dependent adhesions to endothelial cells at sites of inflammation. This phenomenon was investigated under conditions of flow in vitro using isolated human neutrophils and monolayers of HUVEC. The efficiency of conversion of neutrophil rolling to stable adhesion in this model was >95%. Neither anti-CD11a nor anti-CD11b antibodies(More)
Surface wetting is an important phenomenon in many industrial processes including microand nanofluidics. The wetting characteristics depend on the surface tension forces at the three-phase contact line and can be altered by introducing patterned groove structures. This study investigates the effect of the grooves on the transition in the wetting behavior(More)
This unit describes a hydrodynamic assay to study the relative importance of various receptor/ligand interactions in cell-cell and cell-substrate adhesion and to quantitate the strength of their binding. The basic protocol describes how to assemble the single-chamber flow system with the substrate, add the cells in suspension, and record the experiment on(More)