Biomedical Engineering and Bioengineering Commons^™

Growth Plate Cartilage: Understanding The Contribution Of Adhesion To Column Formation And Matrix Structure, Sydney E. Greer

Theses & Dissertations

Throughout fetal and adolescent development, bone growth is regulated by fine-tuned and controlled maturation of chondrocytes through a cartilaginous template called the growth plate. Bone growth rate is controlled through cell enlargement and extracellular matrix deposition, while the polarized arrangement of proliferative chondrocytes into columns aligned with the long axis of the bone potentiate growth. Chondrocytes are surrounded by a complex three-dimensional arrangement of matrix molecules, all of which are secreted by chondrocytes and assembled/remodeled to support the biological functions of the cell. Adhesion receptors found on the cell membrane of chondrocytes are crucial to the organization of matrix proteins …

To Hear Or Not To Hear: How “Best Interest” Determinations Can Help In The Cochlear Implant Debate, Tessa Wright

Minnesota Journal of Law, Science & Technology

No abstract provided.

The Future Is Now In Twisted Coil Polymer Actuators (Tcpa), Ryan Ronquillo

Electronic Theses and Dissertations

This thesis aimed to fabricate and test twisted coiled polymer actuators (TCPA) to understand the mechanical and thermal aspects of this artificial muscle fiber. The purpose of this thesis was to find a linear relationship using the LVDT sensor, fabricating TCPA fibers, and interpreting the data. The project tested whether nylon/polymer could be used as a better artificial muscle fiber.

This research accomplished three goals: (1) designing and fabricating a system capable of creating supercoiled muscle fibers consistently, (2) calibrating the Linear Variable Differential Transformer (LVDT) and Core, and (3) analyzing/interpreting the data of the Twisted Coiled Polymer Actuators (TCPA) …

Multichannel Modulation Of Depolarizing And Repolarizing Ion Currents Increases The Positive Rate-Dependent Action Potential Prolongation, Candido Cabo

Publications and Research

Prolongation of the action potential duration (APD) could prevent reentrant arrhythmias if prolongation occurs at the fast excitation rates of tachycardia with minimal prolongation at slow excitation rates (i.e., if prolongation is positive rate-dependent). APD prolongation by current anti-arrhythmic agents is either reverse (larger APD prolongation at slow rates than at fast rates) or neutral (similar APD prolongation at slow and fast rates), which may not result in an effective anti-arrhythmic action. In this report we show that, in computer models of the human ventricular action potential, the combined modulation of both depolarizing and repolarizing ion currents results in a …

Breast Tissue Tumor Detection Using Microstrip Patch Antenna With Defected Ground Structure, Nihal F. F. Areed, Hamdi Ahmed El Mikati, Laila T. Rakha

Mansoura Engineering Journal

This work proposes a slotted microstrip patch antenna with an inset feed and defective ground structure (DGS). The proposed antenna is built with Roger-RT/5880 (Ԑr=2.2) as the substrate material for X-band application with a resonant frequency of 10 GHz. The proposed design has been simulated using Finite Element Method (FEM) and the results of bandwidth and gain read about 700MHz and 8dB; respectively. The suggested design is compared with previously published equivalent designs in light of the most recent research. The comparison reveal that that the suggested design with tuned dimensions offers higher gain and wider bandwidth than what has …

Redesigning Nasogastric Feeding Tubes To Prevent Dislodgement, Sydney Ruth Rester, Shelby Lynn Berry

Honors Theses

Seniors at the University of Mississippi studying biomedical engineering complete a senior project that seeks to solve a problem in healthcare. Our team, composed of Sydney Rester, Shelby Berry, Andrew Ulmer, and Alex Bromley, sought to improve care associated with nasogastric feeding tubes. We identified two major problems: clogging and tube dislodgement. To address the problem of dislodgement, the team crafted a new feeding tube design with a balloon attachment. The attachment prevents a patient from pulling the feeding tube out and keeps the tube from dislodging due to normal patient movement. We further determined that our tube should be …

Redesigning Nasogastric Feeding Tubes To Prevent Dislodgement, Shelby Lynn Berry, Sydney Ruth Rester

Honors Theses

Seniors at the University of Mississippi studying biomedical engineering complete a senior project that seeks to solve a problem in healthcare. Our team, composed of Sydney Rester, Shelby Berry, Andrew Ulmer, and Alex Bromley, sought to improve care associated with nasogastric feeding tubes. We identified two major problems: clogging and tube dislodgement. To address the problem of dislodgement, the team crafted a new feeding tube design with a balloon attachment. The attachment prevents a patient from pulling the feeding tube out and keeps the tube from dislodging due to normal patient movement. We further determined that our tube should be …

Implementation Of Methods For Cell Therapy Research And Assessment Of The Impact Of Cryopreservation, Samantha Lynes

Master's Theses

Cell therapy is the administration of living cells into a patient to prevent or treat a variety of diseases and illnesses. The cell therapy industry is rapidly expanding, and continued research is necessary for manufacturing safe and effective therapies. Although cell therapy manufacturing generally involves cryopreservation processes for storage, there are limited standards for cryopreservation processes and assays required to evaluate cell therapies post-thaw, and limited understanding exists about how a recovery period post-thaw could impact cell health. The overall goal of this thesis was to evaluate the effect of cryopreservation and potential subsequent recovery time on cell viability.

Because …

Assesment Of Structure, Function, And Microevolutionary Dynamics Of Extrachromosomal Circular Dna In Chinese Hamster Ovary Cells, Dylan Chitwood

All Dissertations

Chinese hamster ovary (CHO) cell lines are among the most popular expression hosts used in biopharmaceutical manufacturing due to relative ease of culture, capacity to perform human-like post-translational modifications, and non-susceptibility to viruses. However, the intrinsic plasticity of the CHO genome can lead to undesired genetic rearrangements, phenotypic shifts, reduced product quality, and early culture termination that prevents continuous biomanufacturing. A characteristic of plastic and unstable genomes that is poorly understood in CHO cells is extrachromosomal circular DNA (eccDNA). EccDNAs are focal amplifications of the genome that reside in the extranuclear space. These plasmid-like entities are structurally complex and are …

Investigating The Effect Of Pancreatic Cancer Tumor-Derived Extracellular Vesicles On Schwann Cell Activation, Isabel Powers

Biomedical Engineering Undergraduate Honors Theses

Pancreatic cancer is one of the deadliest diseases because it is hard to identify in its early stages, has high chemoresistance, and early metastasis. Because of these traits, it is often associated with perineural invasion (PNI), where the cancer travels to the nervous system. Schwann cells (SC) are associated with both metastasis and PNI when activated. The purpose of this study was to determine if and how pancreatic tumor-derived extracellular vesicles (TEVs) can activate SC in PNI. This experiment was performed by embedding Schwann cells in a hydrogel to model the tumor microenvironment and treating them with isolated extracellular vesicles …

Development Of 3d Ovarian Cancer Spheroids In Vitro And Investigation Of Their Physiological Relevance As Models Of Inherent Chemoresistance, Amanda Murray

Honors College Theses

Ovarian cancer is the sixth leading cause of death among women worldwide, with an average 5-year survival rate of less than 48%. Current clinical treatment methods for this disease are often deemed ineffective because of the innate chemoresistance of tumors due to their microenvironment and architecture. Accurately mimicking chemoresistance with traditional 2D cultures is difficult; therefore, recent years have seen an increase in 3D culturing methods that create cellular spheroids. These spheroids can serve as models of in vivo tumor characteristics due to their hypoxic core, acidic microenvironment, and increased cell-to-cell interactions. This research aims to (1) refine a 3D …

Motion Analysis Of Feeding Tasks: Brachial Plexus Versus Control Subjects, Madison M. Lovette

ETD Archive

Brachial plexus birth injuries (BPBI) occur in about 0.4 to 4.6 of every 1000 live births due to stretching or tearing of the nerves. Children with BPBI often struggle to perform daily living activities without assistance, including feeding themselves. Upper extremity function is commonly assessed in children with BPBI using the modified Mallet classification, a set of positions representing activities of daily living that are scored according to ability. The hand to mouth position is a Mallet position and is often used to represent feeding tasks in the BPBI population. Establishing this normative data will provide a baseline for comparison …

Investigating The Impact Of International Education On Cultural Understanding, Health Disparities And Collaboration Through Project-Based Learning, Breanna Kilgore

Biomedical Engineering Undergraduate Honors Theses

Global health is an interdisciplinary field emphasizing international health issues, causes, and solutions based on cultural and global understanding. We have all witnessed how crucial global health is with the global COVID-19 crisis that has affected everyone. To effectively work to solve global health issues, people from different backgrounds must work together to complete a common goal. Before problem solving begins, gaining a basic understanding of cultural differences and collaborating with different people is an essential skill to have. Previous studies have demonstrated the usefulness of study abroad experiences and international service-learning opportunities in promoting collaborations, cultural competency and personal …

Optimizing Three-Dimensional Bioengineered Co-Cultures For The Study Of Fibrotic Spinal Cord Injury, Sarah Aly

Biomedical Engineering Undergraduate Honors Theses

Spinal cord injuries (SCIs) have major physical implications on those affected^[1]. There are two main types of scarring that occur after injury; they are known as the glial and fibrotic scar. The injured site causes an altered micro-environment which transforms astrocytes from their normal to reactive state, thus inhibiting axonal regeneration. The effect of reactive astrocytes on fibrotic scarring is not fully understood due to limited study^[2,3]. Using Three-Dimensional (3D) bioengineered co-cultures of astrocytes and neuroblasts the pathological environment can be replicated and manipulated to further the study of fibrotic scarring. Temperature casted co-cultures were successfully …

Physiological Analyses Of Broadband Near-Infrared Spectroscopy And Electrophysiological Measurements In Vivo For Biomedical Applications, Haylea Renguul

Bioengineering Theses - Archive

My thesis concerns analysis of data from optical and electrophysiological measurement tools for calculate potential biomarkers in three biomedical applications: (1) the gastrointestinal immaturity of infants of different ages, (2) prefrontal connectivity in healthy older adults, and (3) hemodynamic-metabolic coherence during vascular occlusion. The first application relied on electrogastrogram (EGG) measurements taken on 81 newborns in a neonatal intensive care unit. Of the 81 babies, 77 were born prematurely. By separating these babies into different gestational age groups and analyzing their EGG data, I was able to find population differences in common EGG analysis parameters. In particular, we found that …

3d Printing With Photopolymerizable Polyester Resins For Resorbable Medical Device Applications, Mathew Murphy Stanford

All Dissertations

In the past decade, the healthcare industry has seen a significant increase in the use of additive manufacturing (AM or “3D printing”) with subsequent improvement in clinical outcomes.As an exceptional AM technology, vat-photopolymerization (VP), often called stereolithography, can create complex structures and has thus been adopted for a range of biomedical applications including surgical guides, temporary implants, and resorbable tissue scaffolds.However, limitations remain in the availability of photopolymerizable resin materials with appropriate mechanical performance, biodegradability, and biocompatibility for application to resorbable medical devices.

The objective of this work was to employ novel photopolymerizable polyester-based macromers in the development of resorbable …

A Comparative Biomechanical Investigation Of Porcine Neonatal And Adult Left Ventricular Tissues, Timothy R. Eastep

Bioengineering Theses - Archive

A current trend in cardiac muscle regeneration and repair is to recreate the biophysical and biomechanical environment of the neonatal hearts, which has been shown to promote cardiac regeneration. This translational need requires thorough understanding of the biomechanical properties of the neonatal hearts. In this study, we aim to (i) characterize the dynamic viscoelastic properties of the neonatal porcine left ventricular (LV) muscle and compare with the adult tissue behavior using a rheometer; (ii) perform histological assessment to identify the cellular and extracellular (ECM) microstructures that contribute to the observed biomechanical differences, and (iii) develop a light sheet imaging protocol …

Exploring The Effects Of Microarchitecture On Astrocyte Behavior And Vascular Remodeling In Spinal Cord Injury, Devin Gerber

Biomedical Engineering Undergraduate Honors Theses

Spinal cord injury (SCI) is a common condition and is characterized by traumatic and progressive damage that results in limited neuron regeneration and thus a restricted recovery. In SCI, the vasculature is also severely damaged, which exacerbates inflammation at the injury site. Specifically, insufficient angiogenesis occurs at the site of injury due to the fibrotic pathological microenvironment1 . SCI also leads to the formation of a fluid-filled cavity and thus gliosis and fibrosis, forming a dense glial and fibrotic scar around the cavity. The microenvironment at the injury site plays a significant role in astrocyte behavior, promoting the transformation of …

Rattus Norvegicus As A Biological Detector Of Clandestine Remains And The Use Of Ultrasonic Vocalizations As A Locating Mechanism, Gabrielle M. Johnston

Master's Theses

In investigations, locating missing persons and clandestine remains are imperative. One way that first responder and police agencies can search for the remains is by using cadaver dogs as biological detectors. Cadaver dogs are typically used due to their olfactory sensitivity and ability to detect low concentrations of volatile organic compounds produced by biological remains. Cadaver dogs are typically chosen for their stamina, agility, and olfactory sensitivity. However, what is not taken into account often is the size of the animal and the expense of maintaining and training the animal. Cadaver dogs are typically large breeds that cannot fit in …

Trace Dna Detection Using Diamond Dye: A Recovery Technique To Yield More Dna, Leah Davis

Master's Theses

This study aspires to find a new screening approach to trace DNA recovery techniques to yield a higher quantity of trace DNA from larger items of evidence. It takes the path of visualizing trace DNA on items of evidence with potential DNA so analysts can swab a more localized area rather than attempting to recover trace DNA through the general swabbing technique currently used for trace DNA recovery. The first and second parts consisted of observing trace DNA interaction with Diamond Dye on porous and non-porous surfaces.

The third part involved applying the Diamond Dye solution by spraying it onto …