Engineering Commons^™

Mitral Valve Imaging And Biomechanics: A Workflow Towards Computational Modeling And Validation, Sam Stephens

Graduate Theses and Dissertations

The mitral valve serves a critical role in healthy cardiac function by ensuring the unidirectional flow of oxygenated blood from the left atrium into the left ventricle. It experiences the highest pressures found within the heart and its closure is the result of a complex interaction of several different structures that, furthermore, are unique to each individual. Despite the valve’s vital role however, the specific function of these constituent structures is not fully understood. This, confounded by its asymmetric, personalized nature, make surgical interventions for the mitral valve far less effective than for its neighboring aortic valve. Efforts to overcome …

Role Of Angiotensin I And Ii On The Tissue Mechanics Of The Aortic Heart Valve Via Receptor Binding And Converting Enzymes, Josh Fahy

Biomedical Engineering Undergraduate Honors Theses

The renin-angiotensin system (RAS) plays a crucial role in the regulation of renal, cardiac, and vascular physiology. This system regulates in vivo blood pressure and fluid balance. As renal blood flow decreases, the kidneys convert prorenin into renin and secrete it into the circulatory system. Renin then converts angiotensinogen into angiotensin I (ang-I). The ang-I is then converted into angiotensin II (ang-II) by the angiotensin-converting enzyme (ACE). Ang-II, a vasoconstrictor, increases blood pressure by causing the blood vessels to narrow. Recent evidence suggests that RAS may be involved in the progression of valve disease, most notably, aortic stenosis.

The first …

Investigation Of The Inherent Chemical, Structural, And Mechanical Attributes Of Bio-Engineered Composites Found In Nature: Alligator Gar’S Exoskeleton Fish Scales, Wayne Derald Hodo

Graduate Theses and Dissertations

The U.S. Army has determined a huge cost savings of up to 51% can be accomplished by reducing the gross vehicle weight, for their personnel carrier, by 33%. To cut cost, composite materials are needed. Man-made composites can have superior material properties (high-strength, high-fracture toughness, and lightweight), but they are prone to delamination at the glued-layered interface. In contrast, fish scale is a natural composite that has the same material properties and, additionally, tend not to delaminate.

The focus of this study was to learn how nature integrates hard and soft materials at each length scale to form a layered …