Biomedical Engineering and Bioengineering Commons^™

Improving The Monitoring Of Post-Operative Patient Mobility, Owen T. Lacey, Alexandria Magyar-Averin, Elena Ewing, Samuel Elliott, Cameron Lazor

Williams Honors College, Honors Research Projects

Patient post-operative care is essential in attaining positive patient outcomes. To ensure proper blood circulation for recovery and healing is achieved, a patient's mobility is monitored. However, medical professionals aren't always available to continuously monitor patient progress. The clinical need for a medical device to monitor and quantify patient movement automatically is derived and addressed here. By designing a novel device and associated code, an engineering solution to this clinical need can be developed to monitor and improve patient post-operative outcomes in the absence of a medical professional. After completing research on the clinical need and gathering information from stakeholders …

Pandemic Healthcare: Face Shield Modification, Nathan Giunto, Sefra Manos, Brandon Ross, Catherine Seno, Catherine Howell

Williams Honors College, Honors Research Projects

Current face shields used in home and institutional healthcare settings create hardships for their wearers, which makes normal work routines more difficult. Recent mandates require healthcare workers to wear both surgical masks as well as plastic face shields when tending to patients. Unfortunately, the majority of face shields have been designed for hospital settings, which does not address the specific requirements for in-home therapist use. Some of the issues include their restrictive size, tendency to fog, susceptibility to glare, and sterilization and re-use issues. Our team proposes to design a face shield for homecare occupational therapists that addresses their unique …

Augmenting Structure/Function Relationship Analysis With Deep Learning For The Classification Of Psychoactive Drug Activity At Class A G Protein-Coupled Receptors, Hannah Willow Shows

Browse all Theses and Dissertations

G protein-coupled receptors (GPCRs) initiate intracellular signaling pathways via interaction with external stimuli. [1-5] Despite sharing similar structure and cellular mechanism, GPCRs participate in a uniquely broad range of physiological functions. [6] Due to the size and functional diversity of the GPCR family, these receptors are a major focus for pharmacological applications. [1,7] Current state-of-the-art pharmacology and toxicology research strategies rely on computational methods to efficiently design highly selective, low toxicity compounds. [9], [10] GPCR-targeting therapeutics are associated with low selectivity resulting in increased risk of adverse effects and toxicity. Psychoactive drugs that are active at Class A GPCRs used …

The Regulation Of Small Gtpase Rac1 Phosphorylation, Activation And Subcellular Localization By Δnp63Α, Amjad Ahmed Aljagthmi

Browse all Theses and Dissertations

ΔNp63α, a member of the p53 family of transcription factors, plays a critical role in normal development and human disease. Loss of ΔNp63α expression is associated with increased cancer invasiveness and metastasis. The small GTPase Rac1 is a master regulator of cell motility, and increased Rac1 activity upregulates cell invasion in multiple human cancers. Increased cancer cell invasion associated with ΔNp63α knockdown and Rac1 activation suggests a novel mechanism by which ΔNp63α regulates tumor invasiveness through Rac1. Accordingly, we sought to delineate the effects of ΔNp63α on Rac1 phosphorylation, activation and subcellular localization. We identified a novel ΔNp63α/miR-320a/PKCᵧ signaling pathway …

Minimally Invasive Repair Of Elongated Chordae Tendineae In The Mitral Valve, Walid Abuhashim, Diana Albaba, Austin Ghiates, Rebecca Leiter, Mary Robakowski

Williams Honors College, Honors Research Projects

In the United States, about 4 million people have been estimated to suffer from severe mitral valve regurgitation [5]. Due to the high risks involved, about half of those patients are ineligible for surgery to repair the valve, because of their poor health [6]. Elongation of the chordae tendineae has been found to be one of the significant causes of regurgitation. To address this, the team has developed a device called “Chord Fastener”, which will restore proper function to the valve via shortening of the chordae tendineae [1]. Via this shortening mechanism, the device will reduce mitral valve regurgitation and …

Modeling Of Excitation In Skeletal Muscle, Sabrina Kinzie Metzger

Browse all Theses and Dissertations

Recent experimental findings in the Rich lab suggest there are important gaps in our understanding of muscle excitability in various disease states. To generate and test hypotheses as well as to determine whether our current understanding of various aspects of muscle excitation can fully explain experimental findings, an accurate model of muscle excitation was needed. Previous studies have modeled excitation of muscle, but in each case, important aspects were omitted. One reason for this is that little effort has been made to accurately simulate muscle action potentials. In this thesis I present progress made towards generation of a model of …

Quantifying Mafenide Release From 3d Printed Phenylalanine-Coumarin Copolyester Scaffolds, Jacob Seeh

Williams Honors College, Honors Research Projects

This project addressed burn wound healing through controlled release of the antibacterial drug mafenide encapsulated by a copolyster into 3D printed scaffolds. Scaffolds were printed at 25^oC and 0.77-1 bar in a cross-hatch pattern with uniform thickness, distance between parallel layers, and diameter then photo-crosslinked. The number of scaffolds available for testing was limited by the amount of polymer that could be synthesized. A high-performance liquid chromatography method was developed specifically for this experiment and used to determine daily release of mafenide from the scaffold into a 2-mL phosphate buffer solution. During the first 24 hours a large …

Feasibility Study To Measure The Impact Of A Specialized Core Exercise On Metabolic Efficiency And Stability During Walking For Above Knee Amputees, Shaye M. Tiell, Sabrina R. Segretario, Serena M. Myers, Emily G. Tully

Williams Honors College, Honors Research Projects

The objective of this study is to determine the feasibility of improving the gait of above-knee (AK) amputees by performing daily core exercises aimed to provide an efficient and stable walking pattern. The goal of the exercise is to strengthen core muscles and form temporary neural connections in the brain aimed at improving metabolic efficiency and stability. We will be implementing the Wright Balance Core 360 Exercise Technique for completion by our subjects. Motion capture technology will be utilized in conjunction with a metabolic oxygen consumption analyzer to collect stability and metabolic efficiency data while amputees walk on a treadmill. …

Regulation Of Osseous Healing By Macrophage-Derived Wnt Ligands, Jefferson Overlin Abaricia

Theses and Dissertations

Osseous healing is regulated by various classes of cells and signaling mechanisms. Of these, Wnt signaling has long been known to be critically important in directing the differentiation of mesenchymal stem cells (MSCs) into osteoblasts during bone healing. However, the source of these Wnt ligands is not known. Recently, a body of literature has arisen finding both beneficial and detrimental effects of macrophage-derived Wnt ligands on the regeneration of other tissues (liver, kidney, heart, and intestine), often by regulating inflammatory activation and stem cell behavior. As macrophages have been well-characterized as orchestrators of healing, their use of Wnt signaling to …

Silk Hydrogels Incorporated With Melanin, Anne Lutz

Browse all Theses and Dissertations

Melanin is a naturally produced pigment found within the human body. Melanin is known for its ability to protect against Ultra Violet light, but also its ability to allow for mechanical protection. Making melanin a good addition to biomedical devices such as hydrogels. Silk hydrogels are weak in their load bearing capabilities but are known for their biocompatibility, biodegradability, and porosity. This makes the silk hydrogel a good material to incorporate melanin into in order to improve the mechanical properties. For the silk solution to form a solid, there must be a presence of both a catalyst and an oxidizer …

Alterations In Cardiac Motions Of The Failing Heart During Direct Mechanical Ventricular Actuation, Benjamin Allyn Schmitt

Browse all Theses and Dissertations

Objectives: Heart failure (HF) refractory to medical management can be effectively treated with mechanical support. However, available devices are frequently associated with complications due to blood contact. Direct cardiac compression (DCC) devices augment LV systolic pump function by externally compressing the heart surface. Direct Mechanical Ventricular Actuation (DMVA) is a unique DCC method providing not only systolic but, importantly, diastolic support. However, DCC in general remains a relatively poorly understood modality. The purpose of this study was to examine DMVA’s effect on restoration of physiologic function in the failing heart. Methods: Global ischemic HF was induced with 5 mins of …

Altered Skeletal Muscle Excitation-Contraction Coupling In The R6/2 Transgenic Mouse Model For Huntington's Disease, Daniel R. Miranda

Browse all Theses and Dissertations

Huntington’s disease (HD) has classically been categorized as a neurodegenerative disorder. However, the expression of the disease-causing mutated huntingtin gene in skeletal muscle may contribute to the symptoms of HD, namely those that involve involuntary muscle contraction. In the R6/2 transgenic mouse model of HD, we previously observed ion channel defects that could contribute to involuntary muscle contraction. Here, in R6/2 muscle we investigated the consequence of these ion channel defects on action potentials (APs), the first step in excitation-contraction (EC) coupling. We found that the ion channel defects were associated with depolarizing the baseline membrane potential during AP trains. …

Augmenting Structure/Function Relationship Analysis With Deep Learning For The Classification Of Psychoactive Drug Activity At Class A G Protein-Coupled Receptors, Hannah Willow Shows

Browse all Theses and Dissertations

G protein-coupled receptors (GPCRs) initiate intracellular signaling pathways via interaction with external stimuli. [1-5] Despite sharing similar structure and cellular mechanism, GPCRs participate in a uniquely broad range of physiological functions. [6] Due to the size and functional diversity of the GPCR family, these receptors are a major focus for pharmacological applications. [1,7] Current state-of-the-art pharmacology and toxicology research strategies rely on computational methods to efficiently design highly selective, low toxicity compounds. [9], [10] GPCR-targeting therapeutics are associated with low selectivity resulting in increased risk of adverse effects and toxicity. Psychoactive drugs that are active at Class A GPCRs used …

Acute Oxygen-Sensing By The Carotid Bodies : The Thermal Microdomain Model, Ryan Joseph Rakoczy

Browse all Theses and Dissertations

The carotid bodies (CB) are peripheral chemoreceptors that detect changes in arterial oxygenation and, via afferent inputs to the brainstem, correct the pattern of breathing to restore blood gas homeostasis. Elucidating the “signal” that couples carotid body sensory type I cell (CBSC) hypoxic mitochondrial inhibition with potassium channel closure has proven to be an arduous task; to date, a multitude of oxygen-sensing chemotransduction mechanisms have been described and altercated (Varas, Wyatt & Buckler, 2007; Gao et al, 2017; Rakoczy & Wyatt, 2018). Herein, we provide preliminary evidence supporting a novel oxygen-sensing hypothesis suggesting CBSC hypoxic chemotransductive signaling may in part …

Exploring Rapid Solidification And Equal Channel Angular Pressing In The Fabrication Of Mg-Based Alloys For Medical Applications, Emily Tom

Dissertations, Master's Theses and Master's Reports

The development of magnesium bioresorbable implants has become increasingly popular due to the increased need for temporary implants and magnesium’s excellent biocompatibility and suitable elastic modulus. Even though magnesium is an excellent candidate, when alloyed with other metals magnesium’s corrosion rate becomes too rapid for bioresorbable medical applications. The investigation into novel processing techniques to control the formation of precipitates to improve mechanical strength and ductility as well as corrosion rates has become of interest. This work investigates the combination of two nonequilibrium processing techniques, rapid solidification (RS) and equal channel angular pressing (ECAP), and the effects it has on …

Biomechanically Inspired Assistive Technology To Restore Movement Of The Upper Limbs After Stroke, Ariel Thomas

Graduate Theses, Dissertations, and Problem Reports (ETD)

A stroke often damages the neural structures responsible for movement. Stroke is a heterogeneous disease, affecting each survivor differently. There are common motor features of a stroke, but even these features vary across time as an individual proceeds through different stages of recovery. The different ways in which stroke motor impairment can present itself are often overlooked, but these differences are fundamental to the understanding of the disease and its recovery. When motor assessments are capable of acquiring information necessary to parse out a detailed profile of each stroke case, this will lead to an improved neuromechanical understanding of the …

Machine Learning Approach For Vigilance State Classification In Mice, Anik Muhury

Theses and Dissertations--Electrical and Computer Engineering

Sleep has a significant impact on cognitive abilities such as memory, reaction time, productivity, and creative thinking; however, there are many aspects of this important activity that are not clearly understood. Over the last century, researchers have developed technology and animal models to assist in the study of sleep. Manual sleep scoring is time consuming, reduces productivity, and is impacted by human scorer subjectivity. On the other hand, automatic sleep stage categorization can enhance consistency and reliability, aiding professionals in identifying sleep related health problems.

In recent times various studies reported significant achievements for automatic vigilance detection and overcome the …

Ogt Glycosylation Of Histones In T Cells May Participate In Systemic Lupus Erythematosus, Jared Luke Ridgeway

Honors Theses

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease that primarily affects women. The etiology is not known yet, but genetics and environmental factors trigger the disease. These epigenetic changes modify gene expression and contribute to the development of the disease. It is known that T cells from patients with lupus overexpress genes that may contribute to the onset and progression of the disease. Dr. Gorelik has shown that OGT (O-linked N-acetyl-Glucosamine Transferase), which is an X-linked gene, is overexpressed in women with SLE. OGT adds b-N-acetylglucosamine (O-GlcNAc) to serine and threonine residues of proteins. …

A Mechanism Behind The Mechanotransduction Of Surface Characteristics In Osteoblasts, Otto J. Juhl Iv

Theses and Dissertations

Biomaterials for use in bone regeneration and healing range from metal and metal alloy implants to hydrogel-based solutions. These materials can be optimized to increase bone healing and integration by improving the mechanical and biological properties. Regardless of the material itself, the cell-substrate interaction is key to the success of the biomaterial once implanted. Substrate surface characteristics such as roughness, wettability, and particle density are well-known contributors to a substrate’s overall osteogenic potential, and therefore the substrate's overall success. Unfortunately, it is still unknown how these substrate surface characteristics are transduced into intracellular signals by cells, preventing specific tailoring of …

Nature-Inspired Material Strategies Towards Functional Devices, Sayantan Pradhan

Theses and Dissertations

Naturally sourced, renewable biomaterials possess outstanding advantages for a multitude of biomedical applications owing to their biodegradability, biocompatibility, and excellent mechanical properties. Of interest in this dissertation are silk (protein) and chitin (polysaccharide) biopolymers for the fabrication of functional biodevices. One of the major challenges restricting these materials beyond their traditional usage as passive substrate materials is the ability to combine them with high-resolution fabrication techniques. Initial research work is directed towards the fabrication of micropatterned, flexible 2D substrates of silk fibroin and chitin using bench-top photolithographic techniques. Research is focused on imparting electrochemical properties to silk proteins using conducting …

Improving Patient-Specific Assessments Of Regional Aortic Mechanics Via Quantitative Magnetic Resonance Imaging With Early Applications In Patients At Elevated Risk For Thoracic Aortopathy, Patrick A. Jones

Theses and Dissertations

Unstable aortic aneurysms and dissections are serious cardiovascular conditions associated with high mortality. The current gold standards for assessment of stability, however, rely on simple geometric measurements, like cross-sectional area or increased diameter between follow-up scans, and fail to incorporate information about underlying aortic mechanics. Displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI) has been used previously to determine heterogeneous circumferential strain patterns in the aortas of healthy volunteers. Here, I introduce technical improvements to DENSE aortic analysis and early pilot application in patients at higher risk for the development of aortopathies. Modifications to the DENSE aortic postprocessing …

Evaluating Neuromuscular Function Of The Biceps Brachii After Spinal Cord Injury: Assessment Of Voluntary Activation And Motor Evoked Potential Input-Output Curves Using Transcranial Magnetic Stimulation, Thibault Roumengous

Theses and Dissertations

Activation of upper limb muscles is important for independent living after cervical spinal cord injury (SCI) that results in tetraplegia. An emerging, non-invasive approach to address post-SCI muscle weakness is modulation of the nervous system. A long-term goal is to develop neuromodulation techniques to reinnervate (i.e. resupply nerve to) muscle fiber and thereby increase muscle function in individuals with tetraplegia. Towards this goal, developing monitoring techniques to quantify neuromuscular function is needed to better direct neurorehabilitation. Assessment of voluntary activation (VA) is a promising approach because the location of the stimulus can be applied cortically using transcranial magnetic stimulation (TMS) …

Applied Machine Learning In Extrusion-Based Bioprinting, Shuyu Tian

Theses and Dissertations

Optimization of extrusion-based bioprinting (EBB) parameters have been systematically conducted through experimentation. However, the process is time and resource-intensive and not easily translatable across different laboratories. A machine learning (ML) approach to EBB parameter optimization can accelerate this process for laboratories across the field through training using data collected from published literature. In this work, regression-based and classification-based ML models were investigated for their abilities to predict printing outcomes of cell viability and filament diameter for cell-containing alginate and gelatin composite hydrogels. Regression-based models were investigated for their ability to predict suitable extrusion pressure given desired cell viability when keeping …

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …

Biocybersecurity: A Converging Threat As An Auxiliary To War, Lucas Potter, Orlando Ayala, Xavier-Lewis Palmer

Engineering Technology Faculty Publications

Biodefense is the discipline of ensuring biosecurity with respect to select groups of organisms and limiting their spread. This field has increasingly been challenged by novel threats from nature that have been weaponized such as SARS, Anthrax, and similar pathogens, but has emerged victorious through collaboration of national and world health groups. However, it may come under additional stress in the 21st century as the field intersects with the cyberworld-- a world where governments have already been struggling to keep up with cyber attacks from small to state-level actors as cyberthreats have been relied on to level the playing field …

Osteocyte Activity And Skeletal Muscle Relative Gene Expression Profiling After Short-Term Muscle Paralysis, Michelle Gelbs

Dissertations and Theses

Mechanical loading is essential for maintaining bone tissue. Reduced mechanical loading has been shown to have a negative effect on bone, and can result in the development of disuse osteoporosis. Disuse models of muscle inactivity and immobilization, like the Botox model used in this study, result in changes in the bone microarchitecture, the mechanisms behind which are not fully understood. In a previous four-week Botox disuse study, skeletally mature 20- week-old rats experienced degradation of intracortical bone, increased vascular porosity, and decreased osteocyte lacunar density in the tibiae. The focus of this study was to explicate a potential source of …

Development Of An Injectable Methylcellulose Hydrogel System For Nucleus Pulposus Repair And Regeneration, Nada A. Haq-Siddiqi

Dissertations and Theses

Low back pain is the most common cause of disability in the world and is often caused by degeneration or injury of the intervertebral disc (IVD). The IVD is a complex, fibrocartilaginous tissue that allows for the wide range of spinal mobility. Disc degeneration is a progressive condition believed to begin in the central, gelatinous nucleus pulposus (NP) region of the tissue, for which there are few preventative therapies. Current therapeutic strategies include pain management and exercise, or surgical intervention such as spinal fusion, none of which address the underlying cause of degeneration. With an increasingly aging population, the socioeconomic …

Development Of A Biaxial Testing System For Research Of Soft Tissue Biomechanics Using Laboratory Models, Tariq Shameen

Dissertations and Theses

The rupture of the cap tissue layer of a fibroatheroma in human coronary vessels is considered the key event leading to the formation of a thrombus and myocardial infarction, resulting in more than half a million deaths in the US every year. In this study, we are interested in investigating the biomechanics of different elastomer materials that can be used as laboratory models to replicate coronary arteries’ ultimate tensile stress (0.2 - 2.08 MPa). To this end, we developed a biomechanical testing system that allows us to characterize the material properties of small samples with high accuracy and precision. We …

Optimization Of Gelatin-Based Cellular Coating Of Msc For Myocardial Infarction Therapy, Kara Amelle Davis

Theses and Dissertations--Chemical and Materials Engineering

Cardiovascular disease remains the number one threat to American lives. During an acute myocardial infarction (AMI), blood flow is blocked and results in the formation of scar tissue. As the body’s immune system responds, inflammatory signaling causes an increase in both scar tissue size and the patient’s risk for further chronic heart failure. In order to reduce the risk of continued heart disease inflammatory signaling must be reduced. Stem cell therapies have the ability to alter the immune system’s pro-inflammatory signal. However, stem cell retention is limited due to blood flow shear. Gelatin methacrylate (GelMA) based coatings have been shown …

Biom 3710: Physiological Systems And Modeling (Syllabus), Aaryani Sajja

Biomedical Engineering Syllabi Archive

Course Description: Fundamentals of control theory and mathematical modeling and analysis as applied to physiological systems.