Biomedical Engineering and Bioengineering Commons^™

Modulated Properties Of Fully Absorbable Bicomponent Meshes, Shawn Peniston

All Dissertations

Current meshes used for soft-tissue repair are mostly composed of single component, nonabsorbable yarn constructions, limiting the ability to modulate their properties. This situation has left the majority of soft tissue repair load-bearing applications to suffer distinctly from undesirable features associated, in part, with mesh inability to (1) possess short-term stiffness to facilitate tissue stability during the development of wound strength; (2) gradually transfer the perceived mechanical load as the wound builds mechanical integrity; and (3) provide compliance with load transfer to the remodeling and maturing mesh/tissue complex. The likelihood of long-term complications is reduced for fully absorbable systems with …

Novel Vascular Grafts Based On Polyphenol-Stabilized Acellular Tissue Scaffolds, Ting-Hsien Chuang

All Dissertations

The Cardiovascular diseases (CVDs) continue to be the leading cause of morbidity and mortality worldwide. The most common form of CVDs is occlusion of blood flow thus limiting blood supply to specific tissues or organs. Atherosclerosis is a leading cause of coronary heart disease and stroke, which were responsible for more than 25% of deaths in 2004.
The demand for vascular graft is huge. In United States alone, approximately 500,000 coronary artery bypass graft surgeries are performed annually. Synthetic polymers such as Dacron and ePTFE have been successfully applied in large diameter blood vessel prosthesis; however, for small diameter (inner …

Evaluation Of Factors That Modulate Cellular Adipogenesis For Breast Tissue Engineering Strategies, Cheryl Gomillion

All Dissertations

It is estimated that this year more than 200,000 women in the United States will be diagnosed with breast cancer. Treatment for most occurrences of breast cancer will often include surgical removal of the tumorigenic tissue, resulting in a soft tissue defect within the subcutaneous tissue of the skin. Post-surgical reconstruction methods are often sought by patients to restore the aesthetic function of the breast via cellular or non-cellular methods; however, because of complications associated with currently used methods for breast reconstruction, researchers are investigating tissue engineering methods to produce viable autologous adipose tissue for breast reconstruction.
Previous research in …

Development Of Software To Estimate Pressures On The Residual Limbs Of Amputees By Means Of A Pylon Mounted Transducer, Malli K. Yalamanchili

UNLV Theses, Dissertations, Professional Papers, and Capstones

The alignment of prosthesis has been recognized as one of the main factors that determine successful prosthetic outcomes for trans-tibial amputees. Alignment is defined as the relative position and orientation of the prosthetic components. Misalignment can result in changes in the position and orientation of the joints of the leg and moments experienced by them during gait, increases in energy use, and discomfort or even tissue breakdown at the socket/stump interface. Hence it is very important to align the prosthesis in correct manner. Gait analysis can be used to examine the effects of incorrect alignment of the prosthesis during gait. …

An Investigation Of Process Parameters To Optimize The Fiber Diameter Of Electrospun Vascular Scaffolds Through Experimental Design, Steffi Wong

Biomedical Engineering

No abstract provided.

Characterization And Analysis Techniques Of A Dynamic In Vitro Blood-Brain Barrier Model, Ryan Everett Woodhouse

Biomedical Engineering

The blood-brain barrier (BBB) is responsible for maintaining the sensitive environment required by the brain. Although the BBB is necessary for proper functioning of the brain, it acts as an obstacle for doctors attempting to treat neurological disease. For a drug to act upon the brain, it must first pass through the discriminating BBB. For this reason, much research has been performed in recent years in order to create an in vitro model of the BBB on which drugs targeted for the central nervous system may be tested. The main goal of this project is to create an in vitro …

The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., Scott J. Sylliaasen

Master's Theses

Studies are currently being performed to determine the effects of bisphosphonate treatments on the structure and density of bone tissue. One of the pathways for gaining a better understanding of the effects of this and other treatments involves creating a computer simulation. Theory suggests that bone tissue structure and density are directly related to the manner in which the tissue is loaded. Remodeling is the process in which bone tissue is resorbed in areas of low stress distributions, and generated in areas of high stress distributions. Previous studies have utilized numerical methods and finite element methods to predict bone structure …

Aortic Coarctation: Recent Developments In Experimental And Computational Methods To Assess Treatments For This Simple Condition, John F. Ladisa, Charles A. Taylor, Jeffrey A. Feinstein

Biomedical Engineering Faculty Research and Publications

Coarctation of the aorta (CoA) is often considered a relatively simple disease, but long-term outcomes suggest otherwise as life expectancies are decades less than in the average population and substantial morbidity often exists. What follows is an expanded version of collective work conducted by the authors' and numerous collaborators that was presented at the 1st International Conference on Computational Simulation in Congenital Heart Disease pertaining to recent advances for CoA. The work begins by focusing on what is known about blood flow, pressure and indices of wall shear stress (WSS) in patients with normal vascular anatomy from both clinical imaging …

Correction To Mitochondrial Free [Ca2+] Increases During Atp/Adp Antiport And Adp Phosphorylation: Exploration Of Mechanisms, Johan Haumann, Ranjan K. Dash, David F. Stowe, Age D. Boelens, Daniel A. Beard, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Quantification Of Functional Near Infrared Spectroscopy To Assess Cortical Reorganization In Children With Cerebral Palsy, Fenghua Tian, Mauricio R. Delgado, Bilal Khan, Sameer C. Dhamne, George Alexandrakis, Mario I. Romero, Linsley Smith, Dahlia Reid, Hanli Liu, Nancy J. Clegg

Bioengineering Faculty Publications - Archive

No abstract provided.

Importance Of Phase Unwrapping For The Reconstruction Of Microwave Tomographic Images, Tomasz M. Grzegorczyk, Paul M. Meaney, Soon Ik Jeon, Shireen D. Geimer, Keith D. Paulsen

Dartmouth Scholarship

Microwave image reconstruction is typically based on a regularized least-square minimization of either the complex-valued field difference between recorded and modeled data or the logarithmic transformation of these field differences. Prior work has shown anecdotally that the latter outperforms the former in limited surveys of simulated and experimental phantom results. In this paper, we provide a theoretical explanation of these empirical findings by developing closed form solutions for the fie

The Conversion Of Low-Grade Heat Into Power Using Supercritical Rankine Cycles, Huijuan Chen

USF Tampa Graduate Theses and Dissertations

Low-grade heat sources, here defined as below 300 ºC, are abundantly available as industrial waste heat, solar thermal, and geothermal, to name a few. However, they are under-exploited for conversion to power because of the low efficiency of conversion. The utilization of low-grade heat is advantageous for many reasons. Technologies that allow the efficient conversion of low-grade heat into mechanical or electrical power are very important to develop.

This work investigates the potential of supercritical Rankine cycles in the conversion of low-grade heat into power. The performance of supercritical Rankine cycles is studied using ChemCAD linked with customized excel macros …

Time Dependent Fixation And Implantation Forces For A Femoral Knee Component: An In Vitro Study, Travis A. Burgers, Jim Mason, Matthew Squire, Heidi-Lynn Ploeg

Mechanical Engineering Faculty Publications

Implant survival rate is a primary concern for individuals receiving a primary total knee arthroplasty. Loosening is the primary reason for revision surgery and was therefore the focus of the current study. To better understand the mechanics of implant fixation, the time-dependent fixation of a femoral knee component was measured in vitro on three cadaveric femurs. The fixation of each femoral knee component was measured with strain gauged implants for at least 10 minutes on each femoral component. Additionally, impaction forces were measured during the implantation of each component. These forces were 2–6 times less than previously reported. The implantation …

Development Of A Physical Windkessel Module To Re-Create In Vivo Vascular Flow Impedance For In Vitro Experiments, Ethan Kung, Charles A. Taylor

Publications

To create and characterize a physical Windkessel module that can provide realistic and predictable vascular impedances for in vitro flow experiments used for computational fluid dynamics validation, and other investigations of the cardiovascular system and medical devices. We developed practical design and manufacturing methods for constructing flow resistance and capacitance units. Using these units we assembled a Windkessel impedance module and defined its corresponding analytical model incorporating an inductance to account for fluid momentum. We tested various resistance units and Windkessel modules using a flow system, and compared experimental measurements to analytical predictions of pressure, flow, and impedance. The resistance …

Personal Navigation Via High-Resolution Gait-Corrected Inertial Measurement Units, Özkan Bebek, Michael A. Suster, Srihari Rajgopal, Michael J. Fu, Xuemei Huang, M. Cenk Çavu¸So˘Glu,, Darrin J. Young, Mehran Mehregany, Antonie J. Van Den Bogert, Carlos H. Mastrangelo

Mechanical Engineering Faculty Publications

In this paper, a personal micronavigation system that uses high-resolution gait-corrected inertial measurement units is presented. The goal of this paper is to develop a navigation system that uses secondary inertial variables, such as velocity, to enable long-term precise navigation in the absence of Global Positioning System (GPS) and beacon signals. In this scheme, measured zerovelocity duration from the ground reaction sensors is used to reset the accumulated integration errors from accelerometers and gyroscopes in position calculation. With the described system, an average position error of 4 m is achieved at the end of half-hour walks.

Production Of Anatomical Models From Ct Scan Data, John Brennan

Other resources

Rapid Prototyping (RP) technology was conceived in the mid 1980s as a method of manufacturing models, particularly to support the design of new motor vehicles. However as early as 1995 the potential to take data from medical scanners and generate models of patient anatomy to assist clinicians plan complex surgical procedures had been recognised, albeit by researchers rather than the mainstream medical industry. Over the last 15 years the production of preoperative planning models has increased dramatically and moreover, the potential to produce customised implants recognised.

Although RP technology is now established in the medical field work is still on …

Can Spr Be Used To Interrogate The Double Layer Of Nacl, Brandon Kawula

Biomedical Engineering

Solutions of reagent grade salt .1, .01, .001, .0001, .00001M were run through a SPR to see if SPR had enough resolution to detect the formation of the electric double layer. We found that NaCl did in fact return a detectable signal. The signal shape seems to depend on concentration. While more study may need to be done to get definite information it looks like SPR can interrogate the double layer.

Removal Of Low Density Sediments By Vegetative Filters, Brent M. Hall

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The use of vegetative filter strips (VFS) is a longstanding best management practice for the removal of sediment and other pollutants from overland flow. Many attempts have been made to model the effectiveness of a VFS based upon soil, vegetation, and sediment properties, and also upon flow conditions, but little work has been done to investigate the reliability of the existing models when considering sediments, such as microbial pathogens, that have a lower density than the mineral sediments used for development of the models. The objectives of this study were to: 1) quantify the ability of a VFS to remove …

Distribution Of Capillary Transit Times In Isolated Lungs Of Oxygen-Tolerant Rats, Madhavi Ramakrishna, Zhuohui Gan, Anne V. Clough, Robert C. Molthen, David L. Roerig, Said H. Audi

Biomedical Engineering Faculty Research and Publications

Rats pre-exposed to 85% O₂ for 5–7 days tolerate the otherwise lethal effects of 100% O₂. The objective was to evaluate the effect of rat exposure to 85% O₂ for 7 days on lung capillary mean transit time (t¯c) and distribution of capillary transit times (h _c(t)). This information is important for subsequent evaluation of the effect of this hyperoxia model on the redox metabolic functions of the pulmonary capillary endothelium. The venous concentration vs. time outflow curves of fluorescein isothiocyanate labeled dextran (FITC-dex), an intravascular indicator, and coenzyme Q₁ hydroquinone …

Plasma Mediated Molecular Delivery, Richard J. Connolly

USF Tampa Graduate Theses and Dissertations

Non-viral delivery of plasmid DNA has traditionally relied upon physical forces applied directly to target tissues. These physical methods typically involve contact between an applicator and the target tissue and often cause transient patient discomfort. To overcome the contact-dependent limitations of such delivery methodologies, an atmospheric direct current plasma source was developed to deposit ionized gas molecules onto localized treatment sites. The deposition of charged species onto a treatment site can lead to the establishment of an electric field with strengths similar to those used for traditional electroporation. In vitro experiments proved that this technology could transiently permeabilize cell membranes …