Biomedical Engineering and Bioengineering Commons^™

Assessment Of The Biocompatibilty, Stability, And Suitability Of Natural And Synthetic Polymers And Drugs In The Fda Approval Process, Phuong Anh Hoang Nguyen

Biomedical Engineering ETDs

Regulation of the development, production, marketing, and sales of medical pharmaceuticals and devices in the United States fall under the regulatory functions of the Food and Drug Administration (FDA). The current FDA approval process takes an average of 10 years from start to completion, and costs over $100 million. As a result, companies use many different methods to find additional use of their drugs through marketing directly to the physician, or recycling of previously approved drug moieties. In this work, an evaluation of the in vitro and ex vivo biocompatibility of polymers and drugs in different phases of FDA approval …

Detection And Remodeling Of Toxic Amyloid Aggregates By Novel Conjugated Polyelectrolytes, Adeline Marianne Fanni

Biomedical Engineering ETDs

The abnormal misfolding and aggregation of intrinsically disordered proteins into ordered fibrillar amyloid aggregates is recognized as a common pathological event in neurodegenerative disorders (ND) such as Alzheimer’s and Parkinson’s diseases. The key role of fibrillar and pre-fibrillar aggregates in ND makes them ideal biomarkers to better understand disease progression but also for early disease detection and therapeutic intervention. The work described herein was conducted to gain a better understanding of amyloid interaction to lipid membrane and its role in peptide toxicity. This research was also focused on evaluating the fluorescent probe, oligomeric p-phenylene ethynylene (OPE), as an amyloid …

Computational Investigation Of The Interactions Between Bioactive Compounds And Biological Assemblies, Tye D. Martin

Biomedical Engineering ETDs

Small, biologically active molecules with unique properties and applications are potential solutions to a wide range of threats to global health including infectious agents and neurodegenerative disease. Experimental studies on a class of oligomeric p-phenylene ethynylenes (OPEs) have shown potential both as bioactive antimicrobials and fluorescent sensing agents for tracking amyloid-β (Aβ) aggregates found in Alzheimer’s Disease (AD). A second type of small molecule with potential applications in AD therapy, curcumin, has been found to interfere with Aβ fibril growth. Curcumin also attenuates Aβ-membrane interactions and Aβ toxicity. Our goal has been to use computational techniques to better understand the …

A Microfluidics-Based Cross-Flow Filtration Platform For Rapid Processing Of Amphiphilic Biomarkers From Blood, Kiersten D. Lenz

Biomedical Engineering ETDs

Early and accurate detection of bacterial infections can help save lives, prevent the spread of disease, and decrease the overuse of antibiotics. Our team at the Los Alamos National Laboratory has developed novel assays to detect bacterial biomarkers from patient blood at the point-of-care in order to facilitate a universal diagnostic platform. However, these biomarkers are amphiphilic in nature, and this biochemical property causes them to be sequestered by high-density and low-density lipoproteins (HDL and LDL) in the host’s blood. Extraction of the bacterial biomarkers from the lipoprotein complexes is thereby required for the development and deployment of a diagnostic …

Simulation Of A Continuum Tumor Model Using Distributed Computing., Dylan A Goodin

Electronic Theses and Dissertations

Mathematical modeling aims to provide a theoretical framework for understanding tissue dynamics and for establishing treatment response for diseased tissues, such as tumors. Previously published continuum models have successfully represented idealized two-dimensional and three-dimensional tissue for short periods of time. A recently published continuum model of cancer increases model complexity and describes three-dimensional tissue that, due to the required complexity of the geometric multigrid solver, can only be feasibly applied to millimeter-scale simulations. Furthermore, the computational cost for such models has hindered their application in the laboratory and in the clinic. With computational demands greatly outpacing current openMP-based approaches on …

The Effect Of Radial Head Hemiarthroplasty Stem Fit On Radiocapitellar Contact Mechanics: Is Loose Fit Better Than Rigidly Fixed?, Jakub Szmit, Graham J.W. King, James A. Johnson, G. Daniel G. Langohr

Western Research Forum

Background/Methods: Radial head hemiarthroplasty is commonly employed to manage comminuted displaced fractures. With regards to implant fixation, current designs vary with some prostheses aiming to achieve a tight 'fixed' fit, and others utilizing a smooth stem with an over reamed 'loose' fit. The purpose of the present study was to evaluate the effect of radial head hemiarthroplasty stem fit on radiocapitellar contact using a finite element model which simulated both fixed (size-for-size) and loose (1, 2 & 3mm over reamed) stem fits.

Hypothesis: It was hypothesized that a loose stem fit would improve radiocapitellar contact mechanics, with increased contact area …

Fibrinogen, Factor Xiii And Fibronectin: A Biophysical And Kinetic Characterization Of Their Interactions, Frank Fabian

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

The development of recombinant-based liquid fibrin tissue sealants having enhanced hemostatic and wound healing properties will involve understanding as yet not well characterized interactions between fibrinogen, fibrin (Fbn) factor XIII, thrombin and fibronectin. We study these phenomena in the context of comparing plasma derived fibrinogen to recombinant fibrinogen (rFI) produced in the milk of transgenic cows. An abundance of purified γγ and γγ’ FI subspecies enables detailed study of γγ or γγ’ biomonomer and their respective Fbn biopolymer formation as having different substrate behaviors of activated plasma derived factor XIII (pFXIIIa₂b₂). High pressure size exclusion (HPSEC) …

Cooking Hand Multi-Tool, Amanda D. Meares, Amy H. Wilson, Ethan G. Littlejohn, Duania A. Evans

Biomedical Engineering

The purpose of this project was to devise a solution for Jorge Segura, a US Marine who was wounded in Afghanistan and had to have his non-dominant arm amputated above the elbow. His current prosthetic attachments are not suited to cooking tasks, so he needed a way to cook more effectively with either prosthetic attachments or accessibility devices. The main tasks that he needed help with was holding down food on cutting boards and stabilizing pots, pans, and bowls especially when stirring. After background research, exploring commercially available devices, and talking with our challenger, our solution was to design three …

A 3-Dimensional In Silico Test Bed For Radiofrequency Ablation Catheter Design Evaluation And Optimization, Carolyn Teng

Master's Theses

Atrial fibrillation (AF) is the disordered activation of the atrial myocardium, which is a major cause of stroke. Currently, the most effective, minimally traumatic treatment for AF is percutaneous catheter ablation to isolate arrhythmogenic areas from the rest of the atrium. The standard in vitro evaluation of ablation catheters through lesion studies is a resource intensive effort due to tissue variability and visual measurement methods, necessitating large sample sizes and multiple prototype builds. A computational test bed for ablation catheter evaluation was built in SolidWorks® using the morphology and dimensions of the left atrium adjacent structures. From this geometry, the …

Age Dependent Regulation Of Cardiac Sodium Channel Gain Of Function, Madison Nowak, David Ryan King, Steven Poelzing, Seth Weinberg

Biology and Medicine Through Mathematics Conference

No abstract provided.

Identification And Analysis Of Behavioral Phenotypes In Autism Spectrum Disorder Via Unsupervised Machine Learning, Elizabeth Stevens, Dennis R. Dixon, Marlena N. Novack, Doreen Granpeesheh, Tristram Smith, Erik Linstead

Engineering Faculty Articles and Research

Background and objective: Autism spectrum disorder (ASD) is a heterogeneous disorder. Research has explored potential ASD subgroups with preliminary evidence supporting the existence of behaviorally and genetically distinct subgroups; however, research has yet to leverage machine learning to identify phenotypes on a scale large enough to robustly examine treatment response across such subgroups. The purpose of the present study was to apply Gaussian Mixture Models and Hierarchical Clustering to identify behavioral phenotypes of ASD and examine treatment response across the learned phenotypes.

Materials and methods: The present study included a sample of children with ASD (N = 2400), …

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel

University Scholar Projects

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi Patel

Honors Scholar Theses

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …

Seeing Eye To Eye: A Machine Learning Approach To Automated Saccade Analysis, Maigh Attre

Honors Scholar Theses

Abnormal ocular motility is a common manifestation of many underlying pathologies particularly those that are neurological. Dynamics of saccades, when the eye rapidly changes its point of fixation, have been characterized for many neurological disorders including concussions, traumatic brain injuries (TBI), and Parkinson’s disease. However, widespread saccade analysis for diagnostic and research purposes requires the recognition of certain eye movement parameters. Key information such as velocity and duration must be determined from data based on a wide set of patients’ characteristics that may range in eye shapes and iris, hair and skin pigmentation [36]. Previous work on saccade analysis has …

Comparing The Effects Of Fibroblast Growth Factors On Growth Rate Of Human Fibroblast Cell Lines, Tasha Repella

Biomedical Engineering Undergraduate Honors Theses

Numerous studies have demonstrated the usefulness of growth factors in medium formulations to promote proliferation and viability of human fibroblasts in laboratory settings. However, due to the differences in the source and age of fibroblasts, the ability of growth factors like hFGF1 to promote proliferation varies. Equally difficult is the ability of hFGF1 to promote proliferation of diseased fibroblasts due to complexities associated with specific mitochondrial diseases. In this context, we decided to evaluate the potential for novel hyper stable growth factors super hFGF and hFGF1 (shFGF and hFGF1 respectively), to contribute to proliferation of different normal and diseased fibroblasts. …

Methods To Remotely Eliminate Biofilm From Medical Implants Using 2.4 Ghz Microwaves, Brett Glenn

Mechanical Engineering Undergraduate Honors Theses

Infections associated with biofilm growth are usually challenging to eradicate due to their high tolerance toward antibiotics [11, 12]. Biofilms often form on the inert surfaces of medically implanted devices [13]. No matter the sophistication, microbial infections can develop on all medical devices and tissue engineering constructs [12]. Related infections lead to 2 million cases annually in the U.S., costing the healthcare system over $5 billion in additional healthcare expenses [12].

Novel solutions to biofilm’s microbial colonization span the spectrum of engineering and science disciplines. Yet a practical solution still does not exist. The research presented here will explore a …

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 …

The Role Of Gene Expression Noise In Mammalian Cell Survival, Kevin Farquhar

Dissertations and Theses (Open Access)

Drug resistance and metastasis remain obstacles to effective cancer treatment. A major challenge contributing to this problem is cellular heterogeneity. Even in the same environment, cells with identical genomes can display cell-to-cell differences in gene expression, also known as gene expression noise. Gene expression noise can vary in magnitude in a population or in fluctuation time scales, which is influenced by gene regulatory networks.

Currently, it is unclear how gene expression noise from gene regulatory networks contributes to drug survival outcomes in mammalian cells. An isogenic cell line with a noise-modulating genetic system tuned to the same mean is required. …

Deswelling Induced Morphological Changes In Dual Ph And Temperature Responsive Ultra-Low Crosslinked Poly (N-Isopropyl Acrylamide)-Co-Acrylic Acid Microgels, Molla R. Islam, Maddie Tumbarello, L. Andrew Lyon

Engineering Faculty Articles and Research

Poly(N-isopropylacrylamide) microgels prepared without exogenous cross-linker are extremely “soft” as a result of their very low cross-linking density, with network connectivity arising only from the self-crosslinking of pNIPAm chains. As a result of this extreme softness, our group and others have taken interest in using these materials in a variety of bioengineering applications, while also pursuing studies of their fundamental properties. Here, we report deswelling triggered structural changes in poly(N-isopropylacrylamide-co-acrylic acid) (ULC10AAc) microgels prepared by precipitation polymerization. Dynamic light scattering suggests that the deswelling of these particles not only depends on the collapse of …

Analysis Of The Effect Of Corrosion On The Surface Chemistry Of Mild Steel Exposed To Biofuel, Timothy D. Plourde

Theses and Dissertations

The use of biofuels in society is steadily becoming more prevalent. Through this proliferation a concern regarding the role of the fungus Byssochlamys nivea in microbially induced corrosion has surfaced. Through the use of X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscope (SEM) technology, this thesis focused on attempting to determine what effect, if any, Byssochlamys nivea has on the corrosion of mild steel. For this analysis, samples were placed in environments that simulated the conditions of fuel tanks containing the biofuel B20, water, and spores of Byssochlamys nivea for varying lengths of time. However, due to a variety of …

Mobility-Based Models For Advancing Diagnostic/Predictive Healthcare, Elham Rastegari

UNO Student Research and Creative Activity Fair

Functional ability has been always considered as one of the important determining factors of individuals’ health and quality of life. Traditional movement analysis systems require expensive facilities and frequent visits for patients to specialized laboratories. Portability and affordability of wearable sensors along with their improved accuracy and capability of monitoring movement during daily activities make them a potential alternative for analyzing mobility patterns for clinical and health assessment purposes. Wearable-based movement data, when combined with other relevant clinical or laboratory data, could enhance evidence-based healthcare and data-driven Clinical Decision Support Systems (CDSS). Utilizing the data from wearable devices, many researchers …

Concussion Indication Device, Taylor O'Donoghue, Isabel Jellen, Eric Shechter

Biomedical Engineering

In this document we summarize our intent to design and manufacture a device that will be used in conjunction with a football helmet, will detect impact forces to the head, and notify the user to seek out further medical attention when subjected to forces large enough to cause concussions. We describe the large market including all levels of football players and the need for improved technology that will not only be effective in elucidating risks but encouraging players to use the device over the alternatives. To design the device, we have researched the problem of concussions in football and have …

Accelerated Wear Reactor Testing, Tristan Frisella, Daniel Alanis, Kian Ashoubi

Biomedical Engineering

Carbon dioxide accounts for a large amount of global greenhouse gases released into the environment. Because plastic degradation emits carbon dioxide, there has been interest to investigate how much carbon dioxide various plastics generate as they degrade. We have been tasked to create a dehumidifier and carbon dioxide sensor assembly for an accelerated wear testing apparatus that degrades plastic. Several products and literature currently exist that share similarity with our assembly but have not been manufactured to achieve the same combination of measurements we are expecting of our accelerated wear testing device. The following report shall introduce these products and …

Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler

Master's Theses

Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems …

Foot Support Taping Device For Off-Loading Wounds, Andres Fojaco Gomez, Mikaela Williams, Josh Pelegrin

Biomedical Engineering

No abstract provided.

Slit Lamp Ophthalmoscope Redesign, Michael Hostetler, Austin Mattmiller, Alexis Brewer

Biomedical Engineering

The slit lamp ophthalmoscope is used by ophthalmologists for diagnosis of pathologies in the eye. The device is used for identifying ocular diseases or indications of other possible systemic diseases to treat them before the diseases progress. Redesign of the ergonomics and adjustment mechanisms of the slit lamp ophthalmoscope will attempt to improve the compatibility of the device across a greater variety of patients. The wider headrest tower of 12.75 inches, the wider table cutout of 12 inches, and the 12 inches of extension of the headrest tower creates a better ergonomic fit for the patient and doctor. The wider …

Ideomotion Gait Training Thigh Prompt, Kristin Schmidt, Elizabeth Peterson, Dalton Jennings

Biomedical Engineering

This document serves as our project report at its completion for developing thigh prompts to be used with the LiftWalker. In this document we outline our project from its beginning to end. We describe our process from understanding the background and our customer requirements, transforming these customer requirements into engineering specifications, performing the stage gate process, developing and evolving the design, testing the design, and finally drawing conclusions and making recommendations for the future.

Development Of An Astrocyte/Glioma Co-Culture System For Measuring Cellular Dynamics, Urna Kansakar

Doctoral Dissertations

Gliomas are brain tumors that primarily arise from glial cells. Gliomas account for 70% of the brain tumors and they are more prevalent in older adults. About 60% of the people with gliomas experience at least one seizure. Brain tumors can grow and metastasize to neighboring areas, thereby destroying normal brain cells. In a brain tumor microenvironment, both malignant cancer cells and healthy brain cells are present. Studies have shown that astrocytes may have a role in tumor growth in the brain. Monocultures cannot evaluate interactions between two cell types and does not accurately represent in vivo conditions. Thus, a …

Development Of A Counter-Flow Thermal Gradient Microfluidic Device, Shayan Davani

Doctoral Dissertations

This work presents a novel counter-flow design for thermal stabilization of microfluidic thermal reactors. In these reactors, precise control of temperature of the liquid sample is achieved by moving the liquid sample through the thermal zones established ideally through the conduction in the solid material of the device. The goal here is to establish a linear thermal distribution when there is no flow and to minimize the temperature change at flow condition. External convection as well as internal flowinduced effects influence the prescribed thermal distribution. The counter-flow thermal gradient device developed in this study is capable of both stabilizing the …

Aptamer Functionalized Zinc Oxide Field Effect Transistors For Odor Detection, Michael D. Aldridge

Graduate Theses, Dissertations, and Problem Reports (ETD)

Odor detection and identification are complex processes, and tasks that currently only animals do well. There is a pressing need for an electronic nose, or eNose, with good sensitivity, selectivity, and speed that mimics that ability. Food quality control operations, environmental sensing, occupational safety, and the defense sectors all require systems that can rapidly and reliably detect trace levels of volatile organic compounds. The goal of this work is to create a biologically inspired device which can accurately detect and identify odors at concentrations consistent with the most sensitive biological systems.

In order to mimic a natural olfactory system, we …