Biomedical Engineering and Bioengineering Commons^™

Development Of A Muscle Force Optimization Algorithm To Improve Center Of Pressure During Simulated Walking, Lawrence Dean Noble

ETD Archive

The Universal Musculoskeletal Simulator (UMS) was developed at the Cleveland Clinic to facilitate general purpose orthopaedic research that allows investigators to study the in vitro forces applied to bones, tendons and ligaments during simulated exercise of cadaver joint systems. In its original state, the UMS hardware consisted of a rotopod (a specialized hexapod robot), a single rotary tendon actuator and custom LabVIEW software for coordinated control and operation of the system. The focus of this work was to 1) enhance the UMS with a multi-tendon actuator system, 2) develop a muscle force optimization algorithm and evaluate it with a static …

Quantification Of Scenedesmus Dimorphus Growth And Substrate Kinetics For Continuous Photobioreactor Design, Daniela Ribita

ETD Archive

Increasing gas prices, limited fossil fuel resources and U.S. dependence on foreign oil make research in alternative fuels a priority. The feasibility of producing fuels from microalgae is economically dependent on improvements in lipid productivity by the algae. The research presented here focuses on the development of a mathematical model to describe the biomass and lipid productivity in a continuously-operated photobioreactor (PBR) system. Five different cell lysing methods were evaluated for the purpose of improving the methods of analysis of lipid synthesis. The two most promising methods were found to be mortar and pestle and organic solvent cell fractionation methods. …

Algea Suspension Dewatering With An Inclined Gravity Settler, Jing Hou

ETD Archive

Biofuel has been studied for several decades as a feasible substitute for petroleum, which may solve the energy crisis. Having a high oil content and growth rate, algae biofuels have received lots of attention recently, and have been considered as one of the most promising technologies to reduce the dependence of fossil fuels. In the process of producing algae biofuel, the dewatering process constitutes a significant part of the cost of the algae biofuel, impeding progress towards large-scale commercial use. An inclined settler utilizes gravity to separate algae cells from the fluid, with little energy consumption. The separation ability of …

Investigations Of Anatomical Connectivity In The Internal Capsule Of Macaques With Diffusion Magnetic Resonance Imaging, Kyle Andrew Ignatius Taljan

ETD Archive

Understanding anatomical connectivity is crucial for improving outcomes of deep brain stimulation surgery. Tractography is a promising method for noninvasively investigating anatomical connectivity, but connections between subcortical regions have not been closely examined by this method. As many connections to subcortical regions converge at the internal capsule (IC), we investigate the connectivity through the IC to three subcortical nuclei (caudate, lentiform nucleus, and thalamus) in 6 macaques. We show that a statistical correction for a known distance-related artifact in tractography results in large changes in connectivity patterns. Our results suggest that care should be taken in using tractography to assess …

A Left Ventricular Motion Phantom For Cardiac Magnetic Resonance Imaging, Mehmet Ersoy

ETD Archive

The mammalian left ventricle (LV) has two distinct motion patterns: wall thickening and rotation. The purpose of this study was to design and build a low-cost, non-ferromagnetic LV motion phantom, for use with cardiac magnetic resonance imaging (MRI), that is able to produce physiologically realistic LV wall thickening and rotation. Cardiac MRI is continuously expanding its range of techniques with new pulse sequences, including new tissue tagging techniques which allow intra-myocardial deformation to be visualized. An essential step in the development of new cardiac MRI techniques is validating their performance in the presence of motion. MRI-compatible dynamic motion phantoms are …

Assessment Of Circumferential Myocardial Function Using Radial Tagged Mri, Yujaung Kim

ETD Archive

The extent of myocardial abnormalities is related to cardiac disease. The assessment of myocardial function of the left ventricular (LV) described by the LV myocardial deformation plays an important role to understand the effects of cardiovascular disease and therapeutic interventions on LV motion. Cardiac magnetic resonance imaging (CMR) is widely agreed as the most accurate noninvasive imaging modality for the assessment of left ventricular (LV) function. In addition, myocardial-tagging technique can track the myocardial deformation by labeling specific regions. Although the grid tagging is popular in cardiac research use, it has not been adopted into routine clinical examination with unreliable …

A Concept For Direct Control Of Rotary Blood Pump Speed By Inlet Pressure, Ibrahim Seven

ETD Archive

Heart failure remains a major health problem for the world. Heart transplantation is the most effective treatment for end stage heart failure. A major problem with heart transplantation is finding adequate numbers of appropriate donors. The lack of donor numbers in the world creates a significant clinical need for blood pumping devices. The ability of ventricular assist devices to relieve the consequences of less than terminal heart failure further creates a need for assist therapy. Current new ventricular assist devices are built around continuous flow technology. These nonpulsatile assist devices have had major clinical success in relieving symptoms and increasing …

Effect Of Step Change In Growth Speed During Directional Solidification On Array Morphology Of Al-7 Wt Si Alloy, Swapna Pakiru

ETD Archive

No abstract provided.

Measurement Of White Matter Structure Changes In Amyotrophic Lateral Sclerosis Using Fractal Analysis, Zao Liu

ETD Archive

Amyotrophic lateral sclerosis (ALS) is recognized as a motor neuron disorder affecting the structure and function of the brain and neuromuscular system. Very little is known, however, that the nervous system degeneration is dependent on disease phenotypes of ALS. The purpose of this study was to determine the degree of brain white matter (WM) structure degeneration in four ALS patient groups characterized by their clinical signs and neuroimaging measurements. Fractal dimension (FD) of three-dimensional (3D) brain WM images was quantitatively analyzed to evaluate the WM structural complexity, including complexity levels of the WM skeleton, surface and general structures in ALS …

An Assessment Of The Accuracy Of Magnetic Resonance Phase Velocity Mapping In Turbulent Flow Through Orifices, Sahitya Pidaparthi

ETD Archive

Magnetic resonance phase velocity mapping (MRPVM) is an established clinical technique to measure blood flow. The acquired information can be used to diagnose a variety of cardiovascular disease. One of the main limitations of MRPVM is that it cannot quantify the flow under turbulent flow conditions. Such conditions develop in certain cases such as in heart valve stenosis and arterial stenosis. Specifically, heart valve stenosis is a serious disease in which the valve does not open as much as necessary for blood to pass through. As a result, the heart has to overwork to overcome the increased resistance. If untreated, …

Reinforced Chitosan-Based Heart Valve Scaffold And Utility Of Bone Marrow-Derived Mesenchymal Stem Cells For Cardiovascular Tissue Engineering, Mohammad Z. Albanna

Wayne State University Dissertations

Recent research has demonstrated a strong correlation between the differentiation profile of mesenchymal stem cells (MSCs) and scaffold stiffness. Chitosan is being widely studied for tissue engineering applications due to its biocompatibility and biodegradability. However, its use in load-bearing applications is limited due to moderate to low mechanical properties. In this study, we investigated the effectiveness of a fiber reinforcement method for enhancing the mechanical properties of chitosan scaffolds. Chitosan fibers were fabricated using a solution extrusion and neutralization method and incorporated into porous chitosan scaffolds. The effects of different fiber/scaffold mass ratios, fiber mechanical properties and fiber lengths on …

An Investigation Of The Biomechanical Response From Shock Wave Loading To The Head, Alessandra Dal Cengio Leonardi

Wayne State University Dissertations

There is a pressing need for a comprehensive explanation of the mechanism of brain injury after exposure to blast and several hypotheses have been suggested. The focus of this research was to investigate one of the hypotheses for primary brain injury due to blast: multimodal skull flexure. The significance of this research is twofold. First, resolution of the mode of energy transfer and of the induced stresses within the skull-brain system will allow for creations of mitigation/protective techniques/equipment, as well as design of experiments investigating live-cell response using more reliable physical models. Second, the data obtained experimentally will be available …

Finite Element Reconstruction Of Real World Aortic Injury In Near-Side Lateral Automotive Crashes With Conceptual Countermeasures, Aditya Neelakanta Belwadi

Wayne State University Dissertations

Traumatic rupture of the aorta (TRA) remains the second most common cause of death associated with motor vehicle crashes after brain injury. On an average, nearly 8,000 people die annually in the United States due to blunt injury to the aorta. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest. With the advent of more accurate and established human body finite element (FE) models, FE crash reconstruction methods may become a valuable tool when assessing crash scenarios and occupant injury mechanisms.

The current study is …

Differences Between Adult And Pediatric Neck Muscle Stress Due Muscle Recruitment Patterns, Renee Dawson

Wayne State University Dissertations

In 2000 and 2001 an estimated 150,000 children between the ages of 0 and 8 years old were injured or killed in a motor vehicle accident. Despite advances in child safety restraints and vehicle restraints, automobile accidents remain the primary cause of death for children in the 0-8 year old age group. In 1982, in an attempt to reduce the number of deaths and injuries of children, the first child crash test dummy was developed. The responses of this dummy were scaled from the adult response data based on the assumption that children were similar to adults both anatomically and …

Effect Of Distillers Grains Moisture And Inclusion Level In Livestock Diets On Greenhouse Gas Emissions In The Corn-Ethanol-Livestock Life Cycle, Virgil R. Bremer, Andrea K. Watson, Adam J. Liska, Galen Erickson, Kenneth Cassman, Kathryn J. Hanford, Terry Klopfenstein

Adam Liska Papers

A model was previously developed (Biofuel Energy Systems Simulator; www. bess.unl.edu) to predict greenhouse gas (GHG) emissions and net energy yield when ethanol is produced from corn. The model also predicts feedlot cattle, dairy cattle, and swine performance and feed replacement value of ethanol coproducts. Updated equations that predict performance of feedlot cattle fed 0 to 40% of dietary DM as corn wet (WDGS), modified (MDGS), or dry (DDGS) distillers grains plus solubles replacing dry-rolled and high-moisture corn were developed and incorporated into the model. Equations were derived from pen-level performance for 20 finishing studies evaluating WDGS, 4 evaluating MDGS, …

Micromotion And Scarring Do Not Contribute To Failure Of Regenerative Peripheral Neural Interfacing, Nivedita Khobragade

Bioengineering Theses - Archive

Neuroprosthetics facilitate amputees with motor function restoration by interfacing nervous system with artificial limb and enabling control of the prosthetic device by volitional thought. Though such neurointerfacing provides dexterity nearly mimicking natural limb agility, the clinical viability of such prosthetics is limited by the lack of long-term reliability. In central nervous system, these implants fail due to foreign body reaction and glial scar formation around the implant. The cause of decrease in active sites of interfacing in peripheral nervous system, which is less invasive than central nervous system implantation, has not been established. Recently an open architecture, regenerative peripheral neural …

Methodology Of Citrate-Based Biomaterial Development And Application, M. Richard Tran

Bioengineering Dissertations - Archive

Biomaterials play central roles in modern strategies of regenerative medicine and tissue engineering. Attempts to find tissue-engineered solutions to cure various injuries or diseases have led to an enormous increase in the number of polymeric biomaterials over the past decade. The breadth of new materials arises from the multiplicity of anatomical locations, cell types, and mode of application, which all place application-specific requirements on the biomaterial. Unfortunately, many of the currently available biodegradable polymers are limited in their versatility to meet the wide range of requirements for tissue engineering. Therefore, a methodology of biomaterial development, which is able to address …

Investigation Of Neural Correlates Between Perception Of Pain And Hemodynamic Response Measured In The Pre-Frontal Cortex Using Functional Near Infra-Red Spectroscopy, Venkatagiri Krishnamurthy

Bioengineering Dissertations - Archive

Perception of pain is multi-dimensional, comprising three major psychological dimensions: sensory-discriminative, motivational-affective and cognitive-evaluative. This dissertation study investigates the cognitive evaluation of pain, by acquiring functional Near Infra-Red Spectroscopic (fNIRS) measurements from the prefrontal cortex (PFC) areas, during mechanical and thermal pain stimulation induced on the subject's volar forearm. Clustered-wise analysis on the oxy-hemoglobin (HbO) response from specific PFC areas was followed by categorizing the resulting HbO response into early (0.1-12sec) and late (12.1-25sec) phases. For each respective phase, regression analysis was carried between the HbO-derived parameters and behaviorally measured pain rating. The major findings of this study include: (1) …

Novel Applications Of Compressed Sensing To Magnetic Resonance Imaging And Spectroscopy, Sairam Geethanath

Bioengineering Dissertations - Archive

In this work, three novel applications of compressed sensing to MRI have been developed and implemented which accomplish reduction in acquisition time, thereby also enabling increased spatial and/or temporal resolution. The first application is for reducing the acquisition time of conventional 1H magnetic resonance spectroscopic imaging (MRSI), which requires alongeracquisition time than conventional MRI. The implementation involved exploiting the inherent sparsity of the MRSI data in the wavelet domain by the use of Daubechies wavelet. This was demonstrated on an in vitro phantom, 6 healthy human brain MRSI data sets, 2 brain and prostate cancer data sets. The reconstructions were …

Novel ¹H Mr Probes To Interrogate The Tumor Microenvironment, Praveen Kumar Gulaka

Bioengineering Dissertations - Archive

The term "tumor microenvironment" usually refers to the description of the physiological and metabolic conditions within solid tumors (primary or metastatic), and is significantly different from that of normal tissues. Assessment of factors like pH, tissue oxygen tension (pO2) and gene expression in the tumor microenvironment and the ability to image them in vivo can provide useful prognostic information. For example, hypoxia (low pO2), typically distributed heterogeneously in solid tumors, is known to affect both radiation sensitivity and the development of metastases thereby influencing the response to treatment. This dissertation research focuses on the evaluation of novel probes to interrogate …