Biomedical Engineering and Bioengineering Commons^™

Impact Of Percutaneous Transluminal Intervention On Vascular Hypoxia And The Role Of Micro-Calcifications On Atherosclerotic Plaque Rupture, Andrea Corti

Dissertations and Theses

Atherosclerotic disease is initiated by cholesterol build-up beneath the endothelium, which evolves into a fibroatheroma, a lipid-rich plaque covered by a fibrous cap. Many of these plaques are considered as vulnerable, as they grow to occlude the luminal section of the artery (chronically stenotic) or become mechanically unstable with a higher chance of rupturing (rupture-prone). On one hand, chronically stenotic vulnerable plaques are symptomatic lesions that are often treated with Percutaneous Transluminal Intervention (PTI). Unfortunately, approximately 10% of PTI procedures are followed by severe Neointima Hyperplasia (NH), which causes a new occlusion and failure of the implant. A significant precursor …

Low-Intensity Ultrasonic Neuromodulation Of The Rat Hippocampus, Duc Nguyen

Dissertations and Theses

Techniques to non-invasively modulate brain activity are important for mapping human brain circuits, and also for the treatment of a host of neurological and psychiatric disorders marked by aberrant brain activity. Though a wide range of techniques for non-invasive neuromodulation have been proposed, the conventional approaches suffer from significant limitations. Most notably, focal stimulation of deep brain regions is presently only possible with invasive optogenetic and chemogenetic approaches that require craniotomies and genetic access to the brain.

Transcranial focused ultrasound stimulation (tFUS) possesses many of the characteristics desirable from a neuromodulation approach: non-invasiveness, a spatial resolution in the order of …

Development Of A Biaxial Testing System For Research Of Soft Tissue Biomechanics Using Laboratory Models, Tariq Shameen

Dissertations and Theses

The rupture of the cap tissue layer of a fibroatheroma in human coronary vessels is considered the key event leading to the formation of a thrombus and myocardial infarction, resulting in more than half a million deaths in the US every year. In this study, we are interested in investigating the biomechanics of different elastomer materials that can be used as laboratory models to replicate coronary arteries’ ultimate tensile stress (0.2 - 2.08 MPa). To this end, we developed a biomechanical testing system that allows us to characterize the material properties of small samples with high accuracy and precision. We …

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …

Collective Chemotaxis Of Retinal Neural Cells From Drosophila Melanogaster In Controlled Microenvironments, Stephanie Zhang

Dissertations and Theses

More than 172 million people are influenced by a retinal disorder that stems from either age-related or developmental causes. Of those, 1.5 million people endure a developmental retinal disorder. In the developing retina, neural cells undergo a series of highly complicated differentiation and migration process. A main cause of these diseases is abnormal collective migration of neural progenitors hindering the retinogenesis process. However, our grasp of collective migration and signaling molecules, critical to the developing retina, is incompletely understood. Understanding the molecular mechanisms, such as the fibroblast growth factor pathway, that regulate glial and neuronal migration provides decisive insights in …

Design Development And Performance Study Of A Novel Assistive Device For Mobility Of Toddlers And Children With Visual Impairments, Joowon Jun

Dissertations and Theses

Being able to see allows mankind tremendous access to learn about the world, and because so much learning comes visually, children with visual impairments are delayed in developing range of skills: learning own languages, doing activities, socializing with peers, and etc. While children with vision can do virtually all the activities and tasks for granted, children with visual impairment require different types of tools or materials to do same tasks most of time. Amongst all the disadvantages that children with visual impairment have, one of the most critical disadvantageous area that visual impairment brings to toddler is learning to walk. …