Many studies of the human vascular tree have shown that atherosclerosis develops at an early age, with areas of the posterior aorta and branch sites showing the earliest fatty streaks. Closer analysis of the branch points showed that the flow dividers, regions of high shear stress with laminar flow, were relatively protected from fatty streak formation. In contrast, there was a predilection for...

Hemodynamic forces play an important role in the non-uniform distribution of atherosclerotic lesions. Endothelial cells are exposed simultaneously to fluid wall shear stress (WSS) and solid circumferential stress (CS). Due to variations in impedance (global factors) and geometric complexities (local factors) in the arterial circulation a time lag arises between these two forces that can be char...

INTRODUCTION With the 3100B high-frequency oscillatory ventilator (SensorMedics, Yorba Linda, CA, USA), patients' spontaneous breathing efforts result in a high level of imposed work of breathing (WOB). Therefore, spontaneous breathing often has to be suppressed during high-frequency oscillatory ventilation (HFOV). A demand-flow system was designed to reduce imposed WOB. METHODS An external g...

Title of dissertation: SEDIMENT SUSPENSION EVENTS FROM RIPPLE BEDS IN OSCILLATORY FLOW: EXPERIMENTS Philip Leland Knowles Doctor of Philosophy, 2009 Dissertation directed by: Associate Professor Kenneth T. Kiger Department of Mechanical Engineering An experimental sediment flume is used to investigate sediment transport mechanics within an oscillatory turbulent boundary layer over a mobile sedi...

We introduce oscillatory segmented flow as a compact microfluidic format that accommodates slow chemical reactions for the solution-phase processing of colloidal nanomaterials. The strategy allows the reaction progress to be monitored at a dynamic range of up to 80 decibels (i.e., residence times of up to one day, equivalent to 720-14,400 times the mixing time) from only one sensing location. A...

For successful scramjet engine operations, it is important to understand the mechanism of inlet unstart phenomenon. Among various unstarted flow patterns in hypersonic inlets, low-amplitude oscillatory still unclear. Therefore, present study, characteristics non-oscillatory a inlet-isolator model are studied by using numerical analysis with RANS-based OpenFOAM solver. In results, amplitude pres...

OBJECTIVE Atherosclerosis-prone regions of arteries are characterized by complex flow patterns where the magnitude of shear stress is low and direction rapidly changes, termed disturbed flow. How endothelial cells sense flow direction and how it impacts inflammatory effects of disturbed flow are unknown. We therefore aimed to understand how endothelial cells respond to changes in flow direction...