Other Biomedical Engineering and Bioengineering Commons^™

An Experimental Study Of The Morphology Of Dna-Carbon Nanotube Hybrid Structures In Direct Dna Sequencing, Avery P. Davis

Biomedical Engineering Undergraduate Honors Theses

Hybrid structures formed between single-stranded DNA (ssDNA) and single-walled carbon nanotubes (SWCNT) have emerged as promising components in future direct DNA sequencing technologies due to their unique morphological and electronic properties. The nanoscale configuration of these hybrids, including the DNA wrapping angle, pitch, and contour behavior, directly influences their potential for stable electronic readout. This thesis presents an experimental study of DNA-SWCNT hybrid morphology using a fixed, reproducible wrapping protocol designed to minimize environmental variability and isolate the influence of DNA nucleotide sequence on hybrid structure. As described in prior work, this protocol produces well-dispersed hybrids suitable for high-resolution imaging. …

Recreating Fiber Recruitment With Fiber Recruitment Using Additive Manufacturing, Natalia D. Mciver

Biomedical Engineering ETDs

Injured ligaments are often repaired with tendon grafts which may over or under constrain the joint; there is a need for an artificial graft option with the mechanical properties of a native ligament. Crimped fibers within ligaments allow for recruitment which means the viscoelastic properties of stress relaxation and creep are not inversely related. A feasibility study using ACLs and large-scale crimp models to study viscoelasticity, led to an in-depth analysis of the scapholunate interosseous ligament. Using the Modified Kelvin spring-dashpot model, for describing viscoelasticity with a variable stiffness property (time dependent fiber recruitment), we defined the relationship between creep …

Muscle Force Analysis In Patients With Forefoot Amputees And Healthy Subjects During Walking, Anthony Melgar, Dumitru Caruntu, Javier La Fontaine, Luis Venegas, Hafizur Rahman

Research Symposium

Forefoot amputation, a type of partial foot amputation, involves the surgical disarticulation of either the interphalangeal or metatarsophalangeal joints. This procedure not only removes critical joint structures but also alters the positioning of associated muscles. Forefoot amputations significantly affect gait patterns and redistribute plantar pressure maps across the plantar surface of the foot. The phalanges are crucial in absorbing and redistributing plantar pressure during the gait cycle. The absence of phalanges and the loss of metatarsophalangeal joints alter the normal pressure distribution maps, possibly shifting peak pressure from one local foot region to another region of the foot. This research …

Foot And Ankle Exoskeleton, Janet M. Velasquez Cabral, Kathryn C. Hamilton, Grant R. Lautze

Biomedical Engineering

This paper presents a non-motorized foot and ankle exoskeleton to assist persons who have no lower limb or abdominal function. Exoskeletons are defined as “an artificial external supporting structure” [1], they are wearable devices that can be used to assist the capabilities of the human body. Although the exoskeleton must be used with crutches, plantarflexion and dorsiflexion will be implemented within the ankle joint to alleviate strain on the foot and ankle, strategically designed in a way that supports the user so their walking performance is as ideal as possible. Additionally, safety straps will be integrated into the foot portion …

Histological Evidence For The Therapeutic Effect Of Chitosan Nanofibrous Dressing On Acute Skin Wounds In A Rat Model, Mahboubeh Ghanbari, Sayed Ahmadreza Razian, Sara Cartwright, Yury Salkovskiy, Jason Mactaggart, Mark A. Carlson

UNO Student Research and Creative Activity Fair

Introduction: Large-area skin traumas, such as thermal burns, are among the most severe health issues that decrease patients’ quality of life and burden healthcare systems. The CDC estimates that there are 1.1 million burns requiring medical attention each year, with more than 20,000 cases involving at least 25% of the body surface, resulting in 4,500 deaths. In addition, about 10,000 people die from burn-related infections. A promising solution to alleviate this problem is using wound dressings based on biopolymers with inherent wound healing properties and biodegradability. One of these biopolymers is chitosan, which is derived from arthropod shells and exhibits …

The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Background: Disease of the lower extremity arteries (Peripheral Arterial Disease, PAD) is associated with high morbidity and mortality. During disease development, the arteries adapt by changing their diameter, wall thickness, and residual deformations, but the effects of demographics and risk factors on this process are not clear.

Methods: Superficial femoral arteries from 736 subjects (505 male, 231 female, 12 to 99 years old, average age 51±17.8 years) and the associated demographic and risk factor variables were used to construct machine learning (ML) regression models that predicted morphological characteristics (diameter, wall thickness, and longitudinal opening angle resulting from the …

Restoring An Iso:5840-Compliant Pulse Duplicator Device For Hydrodynamic Performance Characterization Of Artificial Cardiac Valves, Denver Eagar

Biomedical Engineering Undergraduate Honors Theses

During the summer of 2021, I was employed as an intern at Dynatek Labs, an implantable prosthetics testing company located in southern Missouri. My primary project was to modernize an abandoned pulse duplicator device and protocol to allow the company to re-enter a market area which they left nearly 15 years prior: heart valve testing. The company halted this initiative due to changes in international testing standards in previous years. The International Standards Organization Cardiac Valves Working Group released the latest version of standards concerning artificial heart valve testing (ISO 5840) in January of 2021. Accordingly, my project required that …

Surface Laser Texturing Of Cocrmo Alloys, Gabriel Dharwadker

Biomedical Engineering Undergraduate Honors Theses

Artificial orthopedic implants such as hip joints suffer from excessive wear due to excess friction between the polyethylene and cobalt-chromium-molybdenum surfaces of the device. This increase in friction causes a fraction of them to give out within ten years. Therefore, to minimize the probability of this happening, recent research has been conducted regarding laser surface texturing of the cobalt-chromium-molybdenum alloy components of artificial joints. These surface textures serve to mimic the native lubrication mechanisms of cartilage in natural joints, which, in a natural joint, lowers the friction. However, the production of these laser surface textures is still a field of …

Breaks In Longitudinal Elastic Fibers Of Human Femoropopliteal Arteries, Elham Zamani

UNO Student Research and Creative Activity Fair

Breaks in Longitudinal Elastic Fibers of Human Femoropopliteal Arteries

Elham Zamani1, Majid Jadidi1

1 Department of Biomechanics, University of Nebraska Omaha, Omaha, NE

Introduction: Elastin is a major protein in the body with half-life >50 years. It is thought that elastic fibers are formed before the postnatal period. In the femoropopliteal artery (FPA), the main artery in the leg, longitudinal elastic fibers are present in External Elastic Lamina (EEL). Our team has studied more than 1000 cadaveric human FPA and has noticed that there are big breaks in their longitudinal elastic fibers in some subjects. Our goal in this work …

Bone And Cartilage Compression Simulator, Karoline M. Wucherer, Benjamin A. Parmentier, Thomasina E. Hinkle

Biomedical Engineering

A device was developed that delivers mechanical loads to bone and soft tissue samples under physiological conditions to aid in the research of tissue engineering bone and cartilage. To begin the design process, a Network Diagram and Gantt Chart were produced to create a general timeline for the project to follow. This allowed us to measure our progress and determine what effects (if any) delays could have on our project.

Improving The Early Detection Of Cardiovascular Toxicity Secondary To Radiotherapy For Lung Cancer Via Patient-Specific Quantitative Magnetic Resonance Imaging, Alireza Omidi

Theses and Dissertations

Purpose: To assess the cardiopulmonary-induced dose variation on the left ventricle (LV) and evaluate the spatiotemporal evolution of cardiac/aortic function following radiotherapy (RT).

Methods: 8 lung cancer patients who were scheduled to receive RT were recruited for this study. Each patient underwent one 4D-CT at baseline. MRI scans including cine GRE, T1/T2, LGE, and 4D-flow were acquired at baseline, 3-months and 6-months post-RT to evaluate the cardiac/aortic function. Finally, image registration was used to assess the cardiopulmonary-induced dose variation on the LV.

Results: Mean RT-dose was minimum during inspiration and systole (at expiration). No significant differences were found in the …

Impact Of Percutaneous Transluminal Intervention On Vascular Hypoxia And The Role Of Micro-Calcifications On Atherosclerotic Plaque Rupture, Andrea Corti

Dissertations and Theses

Atherosclerotic disease is initiated by cholesterol build-up beneath the endothelium, which evolves into a fibroatheroma, a lipid-rich plaque covered by a fibrous cap. Many of these plaques are considered as vulnerable, as they grow to occlude the luminal section of the artery (chronically stenotic) or become mechanically unstable with a higher chance of rupturing (rupture-prone). On one hand, chronically stenotic vulnerable plaques are symptomatic lesions that are often treated with Percutaneous Transluminal Intervention (PTI). Unfortunately, approximately 10% of PTI procedures are followed by severe Neointima Hyperplasia (NH), which causes a new occlusion and failure of the implant. A significant precursor …

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …

Impact Of Hemodynamic Vortex Spatial And Temporal Characteristics On Analysis Of Intracranial Aneurysms, Kevin W. Sunderland

Dissertations, Master's Theses and Master's Reports

Subarachnoid hemorrhage is a potentially devastating pathological condition in which bleeding occurs into the space surrounding the brain. One of the prominent sources of subarachnoid hemorrhage are intracranial aneurysms (IA): degenerative, irregular expansions of area(s) of the cerebral vasculature. In the event of IA rupture, the resultant subarachnoid hemorrhage ends in patient mortality occurring in ~50% of cases, with survivors enduring significant neurological damage with physical or cognitive impairment. The seriousness of IA rupture drives a degree of clinical interest in understanding these conditions that promote both the development and possible rupture of the vascular malformations. Current metrics for the …

Solostand, Hau Nhat Doan, Sydney Gray, Celina Dioso

Biomedical Engineering

The purpose of this scope of work is to highlight the progress and development of SoloStand sponsored by Derek Herrera, chief technical officer and founder of SpinalSingularity. SoloStand is an attachment to a wheelchair that will benefit paraplegics that use wheelchairs. A portable and customizable attachment to a wheelchair will allow the user to do everyday tasks without transferring into a separate standing wheelchair and travel more easily. This document outlines everything that has been done in fulfillment of our senior project requirements.

Finite Element Simulation Of Head Impacts In Mixed Martial Arts, Stephen Tiernan, Aidan Meagher, David O'Sullivan Dr, Eoin O'Kelly Dr

Articles

This study determined brain stress and strain in an unhelmeted sport and correlated this with concussive injuries. Thirteen MMA athletes were fitted with the MiG2.0 Stanford instrumented mouthguard. The mouthguard records linear acceleration and angular velocity in 6 degrees of freedom. Angular acceleration was calculated by differentiation. All events were video recorded, time stamped and reported impacts confirmed. 298 impacts above 10g were recorded during sparring sessions and 153 impacts in competitive events. The competitive events resulted in five concussions which were diagnosed by a medical doctor. The impact with the highest angular acceleration from each sparring session and competitive …

The Tera Multi Terrain Mobility Aid Chassis, Colton Kemp, Daniel Nicoll, Ibrahim Suleiman, Mohammad Alyami

Williams Honors College, Honors Research Projects

The natural environment poses a significant number of obstacles and dynamic settings that makes mobility difficult for those with physical and mobility impairments. To approach this problem, a suspension was designed using inspiration from the early Mars rovers developed by NASA for traversing the varied Martian landscape. The course of the project followed the direction of a start-up through problem identification, early design generation and review, and final design production. The project outcome, through client request and proven market research, aimed to produce a multi-terrain wheelchair. The final product is a kinematic body with mobile front “legs” and a rotational …

Development Of A Clinical Marker-Less Motion Capture System For Patient Monitoring, Abigail Eustace

Electronic Theses and Dissertations

The ability to understand human movement is beneficial for deciding surgical procedures, tracking disease progression over time and helping with patient rehabilitation. The current gold-standard for collecting human movement is the use of 3-dimensional marker-based systems. Several studies have presented the many limitations to the current gold-standard that reduces the number of people who are able to benefit from a gait analysis. Those limitations in the current gold-standard include the requirements of large laboratory space, costly equipment, long instrumentation and collection time, and the potential for motion artifact from markers being placed on the skin. The purpose of this study …

Development Of A Torque-Based Device For The Quantification Of Arm Rigidity In Patients With Parkinson’S Disease, Georgina O. Miller

Theses and Dissertations

Parkinsonian rigidity is caused by the inability of the muscles to relax and extend properly, due to reduced dopamine levels and often begins on one side of the body before spreading contralaterally. The current standard for determining joint rigidity in a clinical setting is a test completed by the clinician based on the feel of the relaxed wrist and elbow joints as they are passively flexed and extended and a series of ordinal rating scales, the Movement Disorder Society’s – Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Hoehn and Yahr Scale (H&Y), and Parkinson’s Disease Questionnaire-39 (PDQ-39). These methods are used …

The Impact Of Aging And Mechanical Injury On Alveolar Epithelial And Macrophage Responses In Acute Lung Injury And Inflammation, Michael S. Valentine

Theses and Dissertations

Patients with severe lung pathologies, such as Acute Respiratory Distress Syndrome (ARDS), often require mechanical ventilation as a clinical intervention; however, this procedure frequently exacerbates the original pulmonary issue and produces an exaggerated inflammatory response that potentially leads to sepsis, multisystem organ failure, and mortality. This acute lung injury (ALI) condition has been termed Ventilator-Induced Lung Injury (VILI). Alveolar overdistension, cyclic atelectasis, and biotrauma are the primary injury mechanisms in VILI that lead to the loss of alveolar barrier integrity and pulmonary inflammation. Stress and strains during mechanical ventilation are believed to initiate alveolar epithelial mechanotransduction signaling mechanisms that contribute …

Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue

Biomedical Engineering Undergraduate Honors Theses

In the field of bedside cardiac diagnostic imaging, Doppler Ultrasound (DU) is the gold standard for diagnosing heart conditions. The largest benefit of DU is its ability to noninvasively image cardiac flow and allow the estimation of blood velocity and quantification of anatomical disease. However, to get correct velocity estimation, the position of the transducer in relation to the flow field needs to be known. This is the problem of angle/direction dependency and limits DUs accuracy when imaging in areas where perfect alignment or exact position of the transducer in relation to flow field is not possible or known, such …

Distribution And Localization Of Novel Iodine Nanoparticles In The Human Glioma 1242 Growing In The Brains Of Mice, Benjamin Billings

Honors Scholar Theses

Observing and designing the in vivo distribution and localization of therapeutic nanoparticles is an essential aspect of developing and understanding novel nanoparticle- based medical treatments. This study investigates novel PEGylated Iodine-based nanoparticles (INPs), an alternate composition to the more widely researched gold nanoparticles (AuNPs), which may help avoid adverse effects associated with AuNPs, such as potential toxicity and skin discoloration, when used in similar applications. Determining the localization of the novel INPs within murine brains containing human glioma U-1242MG cells is critical in assisting the development of radiation dose enhancement therapy for this aggressive cancer. Radiation dose enhancement utilizes the …

Extraction And Analysis Of Vector Flow Imaging Data In A Pediatric Population, Bailey Stinnett

Biomedical Engineering Undergraduate Honors Theses

Vector flow imaging (VFI) is a new ultrasound technology that provides real time, angle-independent visualization of flow velocities in the heart and great vessels. Thus far, VFI has been used for superficial applications due to the limited penetration depth of available transducer probes; however, this depth in smaller pediatric patients enables adequate aortic views. In this project, VFI was used to study pediatric aortic stenosis (PAS)—a congenital heart defect that results in the narrowing of the aorta and/or aortic valve. The decision to refer PAS patients for surgical or catheter-based intervention is initially based on Doppler ultrasound. VFI is potentially …

Eigenstrain As A Mechanical Set-Point Of Cells, Shengmao Lin, Marsha C. Lampi, Cynthia A. Reinhart-King, Gary C.P. Tsui, Jian Wang, Carl A. Nelson, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Cell contraction regulates how cells sense their mechanical environment. We sought to identify the set-point of cell contraction, also referred to as tensional homeostasis. In this work, bovine aortic endothelial cells (BAECs), cultured on substrates with different stiffness, were characterized using traction force microscopy (TFM). Numerical models were developed to provide insights into the mechanics of cell–substrate interactions. Cell contraction was modeled as eigenstrain which could induce isometric cell contraction without external forces. The predicted traction stresses matched well with TFM measurements. Furthermore, our numerical model provided cell stress and displacement maps for inspecting the fundamental regulating mechanism of cell …

Feasibility Of Using An Equilibrium Point Strategy To Control Reaching Movements Of Paralyzed Arms With Functional Electrical Stimulation, Matthew Huffman

ETD Archive

Functional electrical stimulation (FES) is a technology capable of improving the quality of life for those with the loss of limb movement related to spinal cord injuries. Individuals with high-level tetraplegia, in particular, have lost all movement capabilities below the neck. FES has shown promise in bypassing spinal cord damage by sending electrical impulses directly to a nerve or muscle to trigger a desired function. Despite advancements in FES, full-arm reaching motions have not been achieved, leaving patients unable to perform fundamental tasks such as eating and grooming. To overcome the inability in current FES models to achieve multi-joint coordination, …

Mimicking Blood Rheology For More Accurate Modeling In Benchtop Research, Lindsey Webb

Honors Undergraduate Theses

To confirm computer simulations and Computational Fluid Dynamics (CFD) analysis, benchtop experiments are needed with a fluid that mimics blood and its viscoelastic properties. Blood is challenging to use as a working fluid in a laboratory setting because of health and safety concerns. Therefore, a blood analogue is necessary to perform benchtop experiments. Viscosity is an important property of fluids for modeling and experiments. Blood is a shear thinning fluid, so it has a decreasing viscosity with higher shear rates. This project seeks to create a blood mimicking fluid for benchtop laboratory use. Numerous fluids with different combinations of water, …

Wearable Hearing Accessory Technology, Tyler Cindea, Jaime Alcorn, Brooke Draper, Kyle Glascott, Ben Hanna, Robert Thoerner

Williams Honors College, Honors Research Projects

We set out in August 2017 to develop an active noise suppressing device that would be usable both in military and civilian activities. Due to constraints in knowledge and time, we decided our best course of action was to divide the project into two equal projects with the hope to be able to combine them into a single project at the end of the allotted time. This consisted of an active noise suppression device and a passive noise suppression device. The passive device would have no electronic components and the active device would be pure circuitry with no housing. This …

A Novel Approach To Increase Upper Extremity Active Range Of Motion For Individuals With Duchenne Muscular Dystrophy Using Admittance Control, Madeline Catherine Corrigan

Dissertations

Duchenne muscular dystrophy (DMD), a neuromuscular disease with a prevalence of 1 in 3,500-5,000 male births, results in progressive muscle weakness causing loss of independence and imposing the demands of costly and intrusive assistive support and personal care for daily living tasks. Upper extremity function begins to decline while ambulation is still possible and gradually progresses with time, playing a prominent role in loss of independence. Importantly, upper extremity functional limitations exist despite residual muscle strength that is insufficient to lift the arms against gravity. Presently, there exist a number of commercially available assistive devices aimed at augmenting upper extremity …

Chemical And Physical Priming Of Human Mesenchymal Stem Cells To Alter Nonviral Gene Delivery Outcomes, Tyler Kozisek, Andrew Hamann, Amy Mantz, Mathias Schubert, Eva Schubert, Angela K. Pannier

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

Human Mesenchymal Stem Cells: Human mesenchymal stem cells (hMSCs) are a multipotent cell, meaning they are able to differentiate into a more mature cell type, such as osteocytes, chondrocytes, and adipocytes, that are found in numerous tissues in the human body, such as bone marrow, fat, and muscle. Since hMSCs can be derived from adult human tissues, they do not have the same ethical concern associated with them as other stem cells, such as embryonic stem cells. Due to hMSCs multipotency and ease of obtaining, they have become one of the most widely researched stem cell types in areas such …

Acl Reconstruction Results In Alterations For Force Control Variability During Multidirectional Force Production, Amelia S. Lanier

UNO Student Research and Creative Activity Fair

After anterior cruciate ligament (ACL) rupture most will undergo reconstructive surgery. Within the first year after surgery 25% of patients will re-tear their ACL. Most of those injured attempt to return to sports which include running and cutting. The ability to produce appropriate ground reaction forces may be crucial for the successful return to sports without re-injury. Understanding stability of multidirectional ground reaction force (mGRF) production in healthy and ACL reconstructed (ACL-r) patients can lend insight to the high instance of re-injury. Typically, stability has been measured using linear analyses, but these analyses cannot capture the subtle time varying changes …