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Theses/Dissertations

Theses and Dissertations

2011

Articles 1 - 8 of 8

Full-Text Articles in Biomedical Engineering and Bioengineering

Tissue Engineering An Acellular Bioresorbable Vascular Graft To Promote Regeneration, Patricia Wolfe Nov 2011

Tissue Engineering An Acellular Bioresorbable Vascular Graft To Promote Regeneration, Patricia Wolfe

Theses and Dissertations

Tissue engineering is an interdisciplinary field that aims to restore, maintain, or improve diseased or damaged tissues. Electrospinning has become one of the most popular means to fabricate a scaffold for various tissue engineering applications as the process is extremely versatile and inexpensive. The ability for electrospinning to consistently create nanofibrous structures capable of mimicking the native extracellular matrix (ECM) is the basis behind why this technique is so successful in tissue engineering. Cardiovascular disease has been the leading cause of death in the United States for over 100 years, and because of this, the need for coronary artery replacements …

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Silk Fibroin-Based Scaffolds For Tissue Engineering Applications, Jennifer Mccool Jul 2011

Silk Fibroin-Based Scaffolds For Tissue Engineering Applications, Jennifer Mccool

Theses and Dissertations

This study focused on the comparison of the electrospun silk scaffolds to the electrospun silk fibroin gel scaffolds. Moreover, this study examined the differences in cross-linking effects of genipin and methanol as well as solvents on the mechanical properties and cell compatibility of the scaffolds. Silk scaffolds were electrospun from an aqueous solution or 1,1,1,3,3-hexafluoro-2-propanol (HFIP) without genipin, immediately after 8 % (wt) genipin was added to the solution, and 18 hours after genipin blended with the solution. Uniaxial tensile testing determined that the silk scaffolds electrospun from water exhibit a higher modulus and peak stress than that of the …

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Optimization Of A Tri-Layered Vascular Graft: The Influence Of Cellular And Mechanical Properties, Michael Mcclure Jun 2011

Optimization Of A Tri-Layered Vascular Graft: The Influence Of Cellular And Mechanical Properties, Michael Mcclure

Theses and Dissertations

Electrospinning is a polymer processing technique which allows for the production of nano to micro size fibers and scaffolds which can be composed of numerous synthetic biodegradable materials and natural biopolymers. Natively, elastin and collagen are the main components of vascular tissue. Arranged in a tri-layered structure, they create a specific mechanical environment that can withstand the rigors of circulation. The goal of this study was to develop a mechanically ‘biomimicking’ vascular graft composed of three distinct layers through the process of electrospinning. We hypothesize that the use of bioactive agents such as elastin, collagen, and silk to supplement poly(caprolactone) …

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The Presentation And Perception Of Virtual Textures Through A Haptic Matrix Display Device, Patrick Headley May 2011

The Presentation And Perception Of Virtual Textures Through A Haptic Matrix Display Device, Patrick Headley

Theses and Dissertations

Dynamic, refreshable tactile displays offer a method of displaying graphical information to people who are blind or visually impaired. Texture, which is already used as an effective method to present graphical information in physical tactile diagrams, conceivably constitutes the best way to present graphics through a tactile display. This thesis presents the design of a new low-cost haptic matrix display device capable of displaying graphical information through virtual textures. The perception of virtual textures through the display is examined through three main experiments. The first two experiments examine the perception of square wave gratings through the device. The final experiment …

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Development Of Physiologic Contact Models For Articular Surfaces, John Owen May 2011

Development Of Physiologic Contact Models For Articular Surfaces, John Owen

Theses and Dissertations

The superficial tangential zone (STZ) plays a significant role in normal articular cartilage’s ability to support loads and retain fluids. To date, tissue engineering efforts have not replicated normal STZ function in cartilage repairs. Finite element models were developed to examine the STZ’s role in normal and repaired articular surfaces under different contact conditions. Models were developed by incrementally adding improvements which culminated in contact loading of curved models by permeable and impermeable rigid surfaces and a normal cartilage layer. In the normal STZ, permeability was strain-dependent on volumetric strain; tension-compression nonlinearity modeled collagen behavior. Nonlinear geometry accounted for finite …

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A Novel P300 Speller With Motor Imagery Embedded In A Traditional Oddball Paradigm., Vaishnavi Karnad May 2011

A Novel P300 Speller With Motor Imagery Embedded In A Traditional Oddball Paradigm., Vaishnavi Karnad

Theses and Dissertations

A Brain Computer Interface (BCI) provides a means, to control external devices, through the electrical activity of the brain, bypassing motor movement. Recent years have seen an increase in the application of P300 cognitive potential as a control and/or communication signal for the motor restoration in paralyzed patients, such as those in the later stages of ALS (Amyotrophic lateral sclerosis). Although many of these patients are in locked-in state i.e. where motor control is not possible, their cognition is known to remain intact. The P300 speller paradigm explored in this study relying on this cognition represented by the P300 peak …

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Design And Implementation Of An Eye Blink Controlled Human Computer Interface, Poonam Gwalani Apr 2011

Design And Implementation Of An Eye Blink Controlled Human Computer Interface, Poonam Gwalani

Theses and Dissertations

Advances in Human Computer Interface (HCI) have made this area of research important for improving the standard of living for people with disabilities. An eye blink system is presented to allow people with disabilities to control a standard computer mouse. This system is designed for people who are paralytic with no control over their arms, speech, and anyone who is restricted to only the control of eye and head movements. This system is based on infrared reflectivity to capture and analyze real time eye blink signal of the user. It uses simple economical hardware electronics to emulate the functionality of …

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3d Functional Modeling Of Dbs Efficacy And Development Of Analytical Tools To Explore Functional Stn, Deepak Kumbhare Apr 2011

3d Functional Modeling Of Dbs Efficacy And Development Of Analytical Tools To Explore Functional Stn, Deepak Kumbhare

Theses and Dissertations

Introduction: Exploring the brain for optimal locations for deep brain stimulation (DBS) therapy is a challenging task, which can be facilitated by analysis of DBS efficacy in a large number of patients with Parkinson’s disease (PD). The Unified Parkinson's Disease Rating Scale (UPDRS) scores indicate the DBS efficacy of the corresponding stimulation location in a particular patient. The spatial distribution of these clinical scores can be used to construct a functional model which closely models the expected efficacy of stimulation in the region. Designs and Methods: In this study, different interpolation techniques were investigated that can appropriately model the DBS …

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