Biomedical Engineering and Bioengineering Commons^™

Human Cardiovascular Responses To Simulated Partial Gravity And A Short Hypergravity Exposure, Qingguang Zhang

Theses and Dissertations--Biomedical Engineering

Orthostatic intolerance (OI), i.e., the inability to maintain stable arterial pressure during upright posture, is a major problem for astronauts after spaceflight. Therefore, one important goal of spaceflight-related research is the development of countermeasures to prevent post flight OI. Given the rarity and expense of spaceflight, countermeasure development requires ground-based simulations of partial gravity to induce appropriate orthostatic effects on the human body, and to test the efficacy of potential countermeasures.

To test the efficacy of upright lower body positive pressure (LBPP) as a model for simulating cardiovascular responses to lunar and Martian gravities on Earth, cardiovascular responses to upright …

Long Term Blood Oxygenation Membranes, Joseph V. Alexander

Theses and Dissertations--Biomedical Engineering

Hollow fiber membranes are widely used in blood oxygenators to remove carbon dioxide and add oxygen during cardiopulmonary bypass operations. These devices are now widely used off-label by physicians to perform extracorporeal blood oxygenation for patients with lung failure. Unfortunately, the hollow fiber membranes used in these devices fail prematurely due to blood plasma leakage and gas emboli formation.

This project formed ultrathin (~100nm) polymer coatings on polymer hollow fiber membranes. The coatings were intended to “block” existing pores on the exterior surfaces while permitting high gas fluxes. This coating is synthesized using surface imitated control radical polymerization.

The coating …

Body Armor Induced Changes In The Trunk Mechancial And Neuromuscular Behavior, Rebecca Leigh Tromp

Theses and Dissertations--Biomedical Engineering

While military body armor is used among warfighters for protection on and off the battlefield, it has been suggested to impede performance and act as a risk factor for the development of musculoskeletal disorders, especially low back pain. Apart from personal suffering, low back pain in soldiers is a great economic burden on the US economy. The objective of this study was to quantify the changes in trunk mechanical and neuromuscular behavior following prolonged exposure to body armor compared to exposure without. A crossover study design was used where 12 sex-balanced participants completed a series of tests before and after …

Inhalable Nanocomposites And Anticancer Agents For Cancer Therapy, Nathanael A. Stocke

Theses and Dissertations--Chemical and Materials Engineering

Cancer is designated as the leading cause of mortality worldwide and lung cancer is responsible for nearly 30% of all cancer related deaths. Over the last few decades mortality rates have only marginally increased and rates of recurrence remain high. These factors, among others, suggest the need for more innovative treatment modalities in lung cancer therapy. Targeted pulmonary delivery is well established for treating pulmonary diseases such as asthma and provides a promising platform for lung cancer therapy. Increasing local deposition of anticancer agents (ACAs) and reducing systemic exposure of these toxic moieties could lead to better therapeutic outcomes and …

Investigation Of Phanerochaete Chrysosporium And Clostridium Thermocellum For Improved Saccharification Of Lignocellulose Under Nonsterile Conditions, William E. Simon

Theses and Dissertations--Biosystems and Agricultural Engineering

Current research efforts are directed at developing competitive processes that can utilize lignocellulose as a feedstock for biorefineries. The purpose of this study was to investigate methods of processing lignocellulosic material so that its monosacharides can be more easily accessed for fermentation, the lack of which is hindering the economics and widescale adoption of lignocellulosic biorefining. The monosaccharides are of interest because they can be used by Clostridium beijerinckii downstream of P. chrysosporium and C. thermocellum in a sequential bioprocess to produce butanol. Butanol is an attractive biofuel because it can be utilized without modifying current transportation infrastructure. Butanol is …

Up Regulation Of Heat Shock Protein 70b (Hsp70b) And Ssa1 In Chlamydomonas Reinhardtii Via Hsp70a-Rbcs2 And Psad Promoter, B. Kirtley Amos

Theses and Dissertations--Biosystems and Agricultural Engineering

Fabrication of effective algae cultivation systems adjacent to coal-fired power plants to fixate waste CO₂ would represent a sizable step towards achieving a carbon neutral energy cycle. However, emission gas would elevate the algal cultivation system temperature and decreases its pH without expensive preprocessing. Increased temperature and acidity constitutes a profound stress on the algae. Although stressed algae produce heat shock proteins (HSPs) that promote protein folding and protect against stress, the ordinary biological response is insufficient to protect against coal flue gas. Experimental upregulation of HSPs could make algae respond to the stress caused by high temperatures and …

Target-Directed Biosynthetic Evolution: Redirecting Plant Evolution To Genomically Optimize A Plant’S Pharmacological Profile, Dustin Paul Brown

Theses and Dissertations--Neuroscience

The dissertation describes a novel method for plant drug discovery based on mutation and selection of plant cells. Despite the industry focus on chemical synthesis, plants remain a source of potent and complex bioactive metabolites. Many of these have evolved as defensive compounds targeted on key proteins in the CNS of herbivorous insects, for example the insect dopamine transporter (DAT). Because of homology with the human DAT protein some of these metabolites have high abuse potential, but others may be valuable in treating drug dependence. This dissertation redirects the evolution of a native Lobelia species toward metabolites with greater activity …

Computational Modeling Of Cardiac Biomechanics, Amir Nikou

Theses and Dissertations--Mechanical and Aerospace Engineering

The goal of this dissertation was to develop a realistic and patient-specific computational model of the heart that ultimately would help medical scientists to better diagnose and treat heart diseases. In order to achieve this goal, a three dimensional finite element model of the heart was created using magnetic resonance images of the beating pig heart. This model was loaded by the pressure of blood inside the left ventricle which was measured by synchronous catheterization. A recently developed structurally based constitutive model of the myocardium was incorporated in the finite element solver to model passive left ventricular myocardium. Additionally, an …

Diffuse, Non-Polar Electropermeabilization And Reduced Propidium Uptake Distinguish The Effect Of Nanosecond Electric Pulses, Iurii Semenov, Christian W. Zemlin, Olga N. Pakhomova, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Ca²⁺ activation and membrane electroporation by 10-ns and 4-ms electric pulses (nsEP and msEP) were compared in rat embryonic cardiomyocytes. The lowest electric field which triggered Ca²⁺ transients was expectedly higher for nsEP (36 kV/cm)than forms EP (0.09 kV/cm) but the respective doses were similar (190 and460 mJ/g). At higher intensities, both stimuli triggered prolonged firing in quiescent cells. An increase of basal Ca²⁺ level by N10 nM in cells with blocked voltage-gated Ca²⁺ channels and depleted Ca²⁺ depot occurred at 63 kV/cm (nsEP) or 0.14 kV/cm (msEP) and was regarded as electroporation threshold. These …

Transcranial Near Infrared Spectroscopy And Stimulation Of Prefrontal Cognitive Functions In Young Adults, Snehal Niwrutti Hase

Bioengineering Theses - Archive

Transcranial near infrared stimulation or Low Level Laser Therapy (LLLT) is an innovative technique shown to control neuronal function in cell cultures, animal models and clinical conditions. The aim of this study was to use near infrared spectroscopy (NIRS) to evaluate the physiological and functional effects of LLLT on prefrontal cognitive functions in young healthy adults. This study was divided into two parts: the first part investigated the physiological effects of LLLT and the second investigated the functional effects.The aim of the first part of this study was to explore how a single session of LLLT altered the hemodynamic status …

Measurement Of Cerebral Blood Flow Using Arterial Spin Labeling Method Across Lifespan, Ciwen Wang

Bioengineering Theses - Archive

Arterial Spin Labeling (ASL) is one family of perfusion-weighted contrast imaging techniques of Magnetic Resonance Imaging (MRI) that measures cerebral blood flow by labeling spins in arterial blood with inversion and then waiting for a certain period of time for the labeled arterial blood to enter the imaging plane, and then acquiring MR image at the image plane. In compare with PET, ASL is a noninvasive new technology. But as a new technology, it is not very commonly used because of the relatively low signal to noise ratio, less robust mechanism, and more important, there is no standard for clinical …

Formulation Of Benzoxaborole Drugs In Plla: From Materials Preparation To In Vitro Release Kinetics And Cellular Assays, Saad Sene, Joshua Mclane, Nicholas Schaub, Sylvie Bégu, P. Hubert Mutin, Lee Ligon, Ryan J. Gilbert, Danielle Laurencin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Benzoxaboroles are a family of organoboron molecules, which have been finding over the past few years an increasing number of biological applications, notably for the design of new drugs. Given that these molecules are still relatively new in the biomedical context, very few investigations regarding their formulation have been reported to date. Here, a complete study on the formulation of benzoxaboroles in a biopolymer, poly-l-lactic acid (PLLA), is reported. The incorporation of two small benzoxaboroles, namely the simplest benzoxaborole molecule (BBzx) and the antifungal drug tavaborole (AN2690), inside PLLA films was investigated. Different variations in the film composition and texture …

Astrocytes Increase Atp Exocytosis Mediated Calcium Signaling In Response To Microgroove Structures, Ajay V. Singh, Michael Raymond, Fabiano Pace, Anthony Certo, Jonathan M. Zuidema, Christopher A. Mckay, Ryan J. Gilbert, X. Lucas Lu, Leo Q. Wan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Following central nervous system (CNS) injury, activated astrocytes form glial scars, which inhibit axonal regeneration, leading to long-term functional deficits. Engineered nanoscale scaffolds guide cell growth and enhance regeneration within models of spinal cord injury. However, the effects of micro-/nano size scaffolds on astrocyte function are not well characterized. In this study, a high throughput (HTP) microscale platform was developed to study astrocyte cell behavior on micropatterned surfaces containing 11/4m spacing grooves with a depth of 250 or 500â €...nm. Significant changes in cell and nuclear elongation and alignment on patterned surfaces were observed, compared to on flat surfaces. The …

Understanding The Role Of Colloidal Particles In Electroporation Mediated Delivery, Alisha Peterson

USF Tampa Graduate Theses and Dissertations

Electroporation (EP) is a physical non-viral technique used to deliver therapeutic molecules across the cell membrane. During electroporation an external electric field is applied across a cell membrane and it causes pores to form. These pores then allow the surrounding media containing the therapeutics to diffuse across the membrane. This technique has been specifically studied as a promising gene and drug delivery system. Colloidal particles have also proven to be promising for a variety of biological applications including molecular delivery, imaging, and tumor ablation, due to their large surface area and tunable properties. In more recent years researchers have explored …

Impedance Measurements As A Means To Improve The Biological Response Of Gene Electrotransfer, Lina Fajardo Gomez

USF Tampa Graduate Theses and Dissertations

When an electric field is locally applied to tissues in vivo the uptake of exogenous DNA can be greatly increased. This approach to gene transfer, called electroporation (EP) or gene electro transfer (GET), has potential applications in the treatment of skin disorders, vaccinations, some types of cancer and metabolic diseases. The eect of electric elds on cells and tissues has been studied and related to the uptake of DNA. Tissue impedance changes have been measured as a result of electroporation. The aim of this study is to explore the predictive accuracy of impedance spectroscopy for the success of GET. Mice …

Quantitative Spatial Frequency Fluorescence Imaging In The Sub-Diffusive Domain For Image-Guided Glioma Resection, Mira Sibai, Israel Veilleux, Jonathan T. Elliott, Frederic Leblond, Brian Wilson

Dartmouth Scholarship

Intraoperative 5- aminolevulinic acid induced-Protoporphyrin IX (PpIX) fluorescence guidance enables maximum safe resection of glioblastomas by providing surgeons with real-time tumor optical contrast. However, visual assessment of PpIX fluorescence is subjective and limited by the distorting effects of light attenuation and tissue autofluorescence. We have previously shown that non-invasive point measurements of absolute PpIX concentration identifies residual tumor that is otherwise non-detectable. Here, we extend this approach to wide-field quantitative fluorescence imaging by implementing spatial frequency domain imaging to recover tissue optical properties across the field-of-view in phantoms and ex vivo tissue.

Mechanical Impedance Of Ankle As A Function Of Electromyography Signals Of Lower Leg Muscles Using Artificial Neural Network, Chen Jia

Dissertations, Master's Theses and Master's Reports - Open

This paper reports on the feasibility of developing a model to describe the nonlinear relationship between the mechanical impedance of the human ankle within a specified range of frequency and the root mean square (RMS) value of the Electromyography (EMG) signals of the muscles of human ankle using Artificial Neural Network (ANN). A lower extremity rehabilitation robot — Anklebot was used to apply pseudo-random mechanical perturbations to the ankle and measure the angular displacement of the ankle to estimate the data of ankle mechanical impedance. Meanwhile, the surface EMG signals from the selected muscles were monitored and recorded using a …

Multi-Scale Visualization Of Molecular Architecture Using Real-Time Ambient Occlusion In Sculptor, Manuel Wahle, Willy Wriggers

Mechanical & Aerospace Engineering Faculty Publications

The modeling of large biomolecular assemblies relies on an efficient rendering of their hierarchical architecture across a wide range of spatial level of detail. We describe a paradigm shift currently under way in computer graphics towards the use of more realistic global illumination models, and we apply the so-called ambient occlusion approach to our opensource multi-scale modeling program, Sculptor. While there are many other higher quality global illumination approaches going all the way up to full GPU-accelerated ray tracing, they do not provide size-specificity of the features they shade. Ambient occlusion is an aspect of global lighting that offers great …

Sports Innovations Track Jack, Kyle Kvasnicka

Williams Honors College, Honors Research Projects

Working with Adaptive Sports Ohio we set out to help individuals with handicaps the ability to play and compete in sports and other athletic activities. Our goal was to create a device that will lift a track wheel chair off the ground so that the athlete in the chair is able to practice without movement. Our design had to be economical, stable, transportable, and allow rotation of the rear tires without causing translational movement of the chair. To accomplish this our group modified a screw jack for a car to support the rear axle of the track wheelchair. We then …

Nasa Limited Inflight Lab Sensor, Gregory P. Howard, James C. Hanreck

Williams Honors College, Honors Research Projects

The National Aeronautics and Space Administration (NASA) is currently developing the capabilities needed to send humans to Mars in 2030 for a three year mission. Astronaut health must be monitored monthly during such a lengthy mission. The UA Enterprise Senior Design Team worked to design a reusable, novel blood panel cartridge system to monitor astronaut health and to minimize waste production. Most current cartridges are composed of polydimethylsiloxane (PDMS). PDMS microchannels were fabricated to conduct simple proof of concept experiments for the design of a novel cartridge. To determine an ideal blood cleaning solution, bovine blood will be injected into …