Biomedical Devices and Instrumentation Commons^™

Construction And Performance Optimization Of Bioconjugated Nanosensors For Early Detection Of Breast Cancer And Pro-Inflammatory Diseases, Pooja Gaikwad

Dissertations, Theses, and Capstone Projects

In recent years, nanosensors have emerged as a tool with strong potential in medical diagnostics. Single-walled carbon nanotube (SWCNT) based optical nanosensors have notably garnered interest due to the unique characteristics of their near-infrared fluorescence emission, including tissue transparency, photostability, and various chiralities with discrete absorption and fluorescence emission bands. Additionally, the optoelectronic properties of SWCNT are sensitive to the surrounding environment, which makes them suitable for in vitro and in vivo biosensing. Single-stranded (ss) DNA-wrapped SWCNTs have been reported as optical nanosensors for cancers and metabolic diseases. Breast cancer and cardiovascular diseases are the most common causes of death …

Characterization And Estimation Of Musculoskeletal Pain Using Machine Learning, Boluwatife Faremi

Master's Theses

Traditional scales utilized for recording pain are known to be highly subjective and biased due to inaccuracies in recollecting actual pain intensities. As a result, machine learning (ML) models that are trained using these scores as ground truth are reported to have low performance for objective pain classification because of the huge disparity between what was felt in moments of pain and the scores recorded afterward.

In the present study, two devices were designed for gathering real-time, continuous in-session subjective pain scores and the recording of the autonomic nervous system (ANS) altered endodermal (EDA) activity. 24 participants were recruited to …

Artificial Scaffold And Neural Stem Cell For Neural Regeneration In Rats With Spinal Cord Injury, Krishna Deo Sharma

Student Theses and Dissertations

Spinal cord injury (SCI) is a devastating condition that often leads to permanent loss of sensory and motor function. Unfortunately, current treatments only manage symptoms and do not provide a complete cure. In this study, we investigated the effectiveness of 3D printed scaffolds and nanomaterials (gold nanorods substrate, nanocellulose-lysine, and TEMPO cellulose) in supporting the growth and differentiation of neural stem cells (NSCs) in vitro. We found that these materials were biocompatible, non-toxic, and able to promote the growth and differentiation of NSCs. Additionally, the unique mechanical properties of these nanomaterials make them a promising candidate for use in neuroregeneration …

Validity Of Fitbit And Garmin Devices While Ascending And Descending Flights Of Stairs, Alan Garcia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Two popular wearable fitness device brands are Fitbit and Garmin. The validity of Fitbit and Garmin’s wrist-worn devices in measuring step counts in various settings, such as walking up and down a staircase, is unclear. PURPOSE: To determine if four devices, the Fitbit Charge 2, Fitbit Versa 2, Garmin Fēnix 5 and Garmin Vívosmart HR+ record valid measures of step count when ascending and descending flights of stairs at three different speeds. METHODS: Twenty-eight participants (n=28) were tested individually. Two devices were randomly selected to be placed on each wrist. Participants climbed up and then down one, two, and three …

A Proof Of Concept For Detection Of Palato-Lingual Contact Without Intraoral Electrodes In A Human Participant, Amitava Biswas

Master's Theses

The author of this thesis conceived and investigated an unexpected electrical signal that may not be noticed during regular electroglottography (EGG) when electrodes are conventionally placed on the anterior surface of the throat. It appears that there is a measurable electrical signal from the EGG equipment when electrodes are placed over the frontal cheek (belly of zygomatic muscle), and the tongue is elevated to contact the hard palate, or the tongue is lowered to break the contact. Therefore, this phenomenon is designated as unconventional electroglottography (UEGG, Dr. Steven Cloud, private communication, July 17, 2022).

Two distinctive patterns of waveforms were …

Mitral Valve Imaging And Biomechanics: A Workflow Towards Computational Modeling And Validation, Sam Stephens

Graduate Theses and Dissertations

The mitral valve serves a critical role in healthy cardiac function by ensuring the unidirectional flow of oxygenated blood from the left atrium into the left ventricle. It experiences the highest pressures found within the heart and its closure is the result of a complex interaction of several different structures that, furthermore, are unique to each individual. Despite the valve’s vital role however, the specific function of these constituent structures is not fully understood. This, confounded by its asymmetric, personalized nature, make surgical interventions for the mitral valve far less effective than for its neighboring aortic valve. Efforts to overcome …

Seeing The Big Picture: System Architecture Trends In Endoscopy And Led-Based Hyperspectral Subsystem Intergration, Craig M. Browning

Graduate Theses and Dissertations (2019 - present)

Early-stage colorectal lesions remain difficult to detect. Early development of neoplasia tends to be small (less than 10 mm) and flat and difficult to distinguish from surrounding mucosa. Additionally, optical diagnosis of neoplasia as benign or malignant is problematic. Low rates of detection of these lesions allow for continued growth in the colorectum and increased risk of cancer formation. Therefore, it is crucial to detect neoplasia and other non-neoplastic lesions to determine risk and guide future treatment. Technology for detection needs to enhance contrast of subtle tissue differences in the colorectum and track multiple biomarkers simultaneously. This work implements one …

Sequential Illumination In A Tomographic Microendoscopic Probe For Imaging Tumor Microvasculature, Zachariah Neumeier

Biomedical Engineering Undergraduate Honors Theses

Knowledge of colorectal cancer biology is improving how we approach cancer treatment. Specifically, the tumor microenvironment and abnormal angiogenesis are of particular interest. Optical methods are a prime candidate for research of the tumor microenvironment due to their ability to quantitively assess tissue structure and perfusion in real time. Particularly, the “transport scattering regime” has been identified as a method of obtaining high-resolution images and reflectance spectroscopy data; this light scattering regime has been demonstrated compatible with endoscopic imaging systems. In this study, a proof-of-concept optical imaging system is presented, capable of resolving absorbers within scattering turbid media using a …

Predicting The Progression Of Diabetes Mellitus Using Dynamic Plantar Pressure Parameters, Mathew Sunil Varre

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Diabetic peripheral neuropathy is one of the common complications of type-2 diabetes mellitus (DM). Changes in the intrinsic plantar tissue coupled with repetitive mechanical loads and loss of sensation may lead to foot related complications (skin break down, ulcerations, and amputations) in persons with neuropathy if left untreated. The purpose of this dissertation was to stratify individuals with pre-diabetes, diabetes with and without neuropathy using dynamic plantar pressure parameters during walking, using machine learning algorithms.Methods: Plantar pressure data was collected from one hundred participants during walking with pressure measuring insoles fixed between the feet and thin socks. Simultaneously high-definition …

Development Of A Long-Read Sequencing Protocol To Assess The Precision And Efficacy Of Gene Editing For Duchenne Muscular Dystrophy, Landon Andrew Burcham

Graduate Theses and Dissertations

This work establishes a method for assessing on-target precision due to CRISPR-Cas9 gene editing, especially within the context of exon skipping therapy for Duchenne Muscular Dystrophy. The proposed method utilizes an Oxford nanopore long-read sequencing approach to sequence amplified regions of DNA that have been edited using CRISPR-Cas9. NIH3T3 and C2C12 cell lines were treated with a dual-guide CRISPR-Cas9 system, that targets and deletes exon 23 from the DMD gene in mouse samples. Deletion PCR revealed deletion of exon 23 in both DNA and cDNA samples. Additionally, sequencing using Oxford Nanopore revealed targeted exon 23 deletion as the most prevalent …

Synthesis Of Thiol-Acrylate Hydrogels For 3d Cell Culture And Microfluidic Applications, Anowar Hossain Khan

LSU Doctoral Dissertations

Globally cell culture is an $18.98 billion industry as of 2020, with an 11.6 percent annual growth rate. Drug discovery has an estimated worth of $69.8 billion in 2020 and is predicted to grow to $110.4 billion by 2025. Three-dimensional (3D) cell culture of cancer cells is one of the rapidly growing felids since it better recapitulates in vivo conditions compared to two-dimensional (2D) models. However, it is challenging to grow 3D tumor spheroids outside the body, and some of the existing technology can generate these spheroids outside the human body but poorly mimic in vivo tumor models. Therefore, there …

Creating Reel Designs: Reflecting On Arthrogryposis Multiplex Congenita In The Community, Iris Layadi

Purdue Journal of Service-Learning and International Engagement

Because of its extreme rarity, the genetic disease arthrogryposis multiplex congenita (AMC) and the needs of individuals with the diagnosis are often overlooked. AMC refers to the development of nonprogressive contractures in disparate areas of the body and is characterized by decreased flexibility in joints, muscle atrophy, and developmental delays. Colton Darst, a seven-year-old boy from Indianapolis, Indiana, was born with the disorder, and since then, he has undergone numerous surgical interventions and continues to receive orthopedic therapy to reduce his physical limitations. His parents, Michael and Amber Darst, have hopes for him to regain his limbic motion and are …

Blood–Brain Barrier Breakdown And Astrocyte Reactivity Evident In The Absence Of Behavioral Changes After Repeated Traumatic Brain Injury, Celeste Dunn, Nasya Sturdivant, Sara Venier, Syed Ali, Jeffery Wolchok, Kartik Balachandran

Biomedical Engineering Faculty Publications and Presentations

Repeated traumatic brain injuries (TBIs) cause debilitating effects. Without understanding the acute effects of repeated TBIs, treatment options to halt further degeneration and damage cannot be developed. This study sought to examine the acute effects of blood–brain barrier (BBB) dysfunction, edema, inflammation and behavioral changes after either a single or double TBI using a C57BL/6 mouse model. We examined the effects of one or two TBIs, of either a mild or moderate severity. Double injuries were spaced 7 days apart, and all analysis was performed 24 h post-injury. To examine edema and inflammation, protein levels of glial fibrillary acidic protein …

Experimental And Analysis Of Electromagnetic Characterization Of Biological And Non-Biological Materials In Microwave, Millimeter-Wave, And Terahertz Frequency Bands, Nagma Vohra

Graduate Theses and Dissertations

The goal of this research is to characterize the electromagnetic properties of biological and non-biological materials at terahertz (THz), millimeter-wave, and microwave frequency bands. The biological specimens are measured using the THz imaging and spectroscopy system, whereas the non-biological materials are measured using the microwave and millimeter-wave free-space system. These facilities are located in the Engineering Research Center at the University of Arkansas. The THz imaging system (TPS 3000) uses a Ti-Sapphire laser directed on the photoconductive antennas to generate a THz time domain pulse. Upon using the Fourier Transform, the spectrum of the pulsed THz signal includes frequencies from …

Flash Radiotherapy: Skin Pigmentation As A Non-Invasive Indicator For Radiation-Induced Damage, Brady Mccallister

ENGS 88 Honors Thesis (AB Students)

FLASH ultra-high dose rate radiotherapy (RT) is one of the most rapidly growing subfields of radiation oncology today due to its potential to increase the limits of the therapeutic ratio. The FLASH effect, which includes heightened normal tissue sparing paired with iso-effective tumor cell killing, has been literature documented, in a limited manner, in rodent models, a few large animals, and one clinical patients.

A porcine-based experiment was conducted to test the effects of FLASH RT on normal tissue compared to conventional (CONV) RT. A clinical linear accelerator (LINAC) was reversibly converted to be capable of FLASH RT. A female …

Patient-Specific Finite Element Analysis For Mandibular Fracture Fixation, Ethan Snyder

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis proposes an approach for Finite Element Analysis (FEA) of mandibular fracture fixation. Using a Computerized Tomography (CT) scan of mandible obtained from a specific person, the material characteristics, density and modulus of elasticity, were determined from a set of discrete points within the mandible that are 1mm spaced based on the Hounsfield Units of these points. The mandible geometry was sectioned to simulate a fracture. Muscle and mastication forces were added to replicate post-surgery loading. Using a standard linear miniplate, this material model was compared with two commonly used mandibular cortical shell bone models: isotropic and orthotropic. A …

Surface-Eroding Drug Delivery Films For Sequential And/Or Intermittent Release Of Psychoactive Drugs, Jason Price

Honors Theses

ABSTRACT JASON BLAKE PRICE: Surface-Eroding Drug Delivery Films for Sequential and/or

Intermittent Release of Psychoactive Drugs For patients with psychiatric diseases, adherence to medication schedules, medication

errors, and abuse are common issues. Promising new forms of therapy for these patients, such as micro-dosed lysergic acid diethylamide (LSD), where patients receive 10-20% of a full dose every third day, present further drug delivery challenges. Sequential or intermittent release of drugs from an implanted device could ensure long-term drug compliance, automate drug dosing during the life of the implant, and eliminate potential for abuse and medication errors. To this end, we generated …

Primer Payload System For Higher-Order Multiplex Lamp: Design And Development Of Unit Processes, Tochukwu Dubem Anyaduba

KGI Theses and Dissertations

Design and Development of Platforms for the Application of Loop-mediated Isothermal Nucleic Acid Amplification, LAMP, in the Diagnosis of Polymicrobial Diseases

Tochukwu Dubem Anyaduba, Travis Schlappi (PI)

For the past two decades, several isothermal nucleic acid amplification technologies have emerged. These are mostly in response to the need for robust molecular diagnostic tools amenable to point-of-care and limited-resource settings. Of these, loop-mediated isothermal amplification, LAMP, stands out as a highly specific and rapid alternative to the polymerase chain reaction, PCR. One of LAMP's significant characteristics involves using four essential and two loop (rate increasing) primers to recognize six to eight …

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 …

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 …

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) …

Technology Aiding In Neonatal Lung Developmental Care, Megan Kirk

Undergraduate Honors Theses

In this paper, old as well as new technological findings to decrease premature infant mortality are reviewed. This paper discusses fetal development throughout pregnancy from conception to full-term status as well as fetal lung development specifically from conception until full-term status. Several ideas to rapidly develop and mature fetal lungs are discussed such as mothers ingesting artificial surfactant supplements, either independently or coupled with antenatal corticosteroids, as well as intra-amniotic instillation prior to 28 weeks gestational. Drawbacks regarding these two are mentioned as well such as the fetus’s lungs not being mature enough to use the artificial surfactant leading into …

Machine Learning Approaches For Fracture Risk Assessment: A Comparative Analysis Of Genomic And Phenotypic Data In 5130 Older Men, Qing Wu, Fatma Nasoz, Jongyun Jung, Bibek Bhattarai, Mira V. Han

School of Public Health Faculty Research

The study aims were to develop fracture prediction models by using machine learning approaches and genomic data, as well as to identify the best modeling approach for fracture prediction. The genomic data of Osteoporotic Fractures in Men, cohort Study (n = 5130), were analyzed. After a comprehensive genotype imputation, genetic risk score (GRS) was calculated from 1103 associated Single Nucleotide Polymorphisms for each participant. Data were normalized and split into a training set (80%) and a validation set (20%) for analysis. Random forest, gradient boosting, neural network, and logistic regression were used to develop prediction models for major osteoporotic fractures …

Rapid Antibiotic Susceptibility Testing Platform For Direct Clinical Samples, Terrance Zhang

Honors Scholar Theses

Infectious diseases and septicemia are two of the major causes of death in the U.S., necessitating rapid treatment of septic patients with proper, efficacious antibiotics. Unfortunately, the emergence and spread of multidrug-resistant bacteria are continuously being aggravated by an abuse in antibiotic prescription at a clinical and agricultural level. It is known that antibiotic resistance evolves through the sequential accumulation of multiple mutations in bacteria, which is accentuated by prolonged exposure of bacteria to ineffective antibiotics when implementing traditional septicemia treatment. The goal of this project is to develop a novel, easy-to-use AST platform for rapid antimicrobial susceptibility profiling to …

Artifact Identification For Blood Pressure And Photoplethysmography Signals In An Unsupervised Environment, Pooi Khoon Lim

Student Works (2020-2029)

Physiological signals play a significant role in clinical diagnosis, it always acts as a major input of a decision support system. However, the physiological signal is easily corrupted by different factors especially motion artifacts. Several research works have been tried to recover the underlying physiological signal by suppressing the artifact. However, not much attention has been paid to situation where the artifact is too extreme and the artifact suppression is not possible. In this situation, physiological signal quality must be evaluated before any further assessment. In this study, an automated artifact detection algorithm was developed for Blood Pressure and PPG …

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 …

Diffuse Reflectance Spectroscopy To Quantify In Vivo Tissue Optical Properties: Applications In Human Epithelium And Subcutaneous Murine Colon Cancer, Gage Joseph Greening

Graduate Theses and Dissertations

Colorectal cancer is the 4th most common and 2nd deadliest cancer. Problems exist with predicting which patients will respond best to certain therapy regimens. Diffuse reflectance spectroscopy has been suggested as a candidate to optically monitor a patient’s early response to therapy and has been received favorably in experimentally managing other cancers such as breast and skin. In this dissertation, two diffuse reflectance spectroscopy probes were designed: one with a combined high-resolution microendoscopy modality, and one that was optimized for acquiring data from subcutaneous murine tumors. For both probes, percent errors for estimating tissue optical properties (reduced scattering coefficient and …

The Time Of Slip Onset During Stance Influences The Characteristics Of The Unconstrained Perturbation, Corbin Rasmussen, Nathaniel Hunt

UNO Student Research and Creative Activity Fair

Falls pose a significant health hazard, resulting in devastating injuries like broken wrists, fractured hips, and traumatic brain injuries that exceed $50 billion in U.S. medical costs. To address these risks, biomechanists have subjected individuals to simulated slips in order to study the factors that lead to falls. These studies have focused on slips that happen immediately after heel-strike and are unnaturally restricted by the methods used to cause the slip. Therefore, the effects of unconstrained slips that occur throughout stance phase are unknown. To address this knowledge gap, we examined the relationship between the timing of slip onset and …

Microfluidic Electrical Impedance Spectroscopy, John J. Foley

Master's Theses

The goal of this study is to design and manufacture a microfluidic device capable of measuring changes in impedance valuesof microfluidic cell cultures. Tocharacterize this, an interdigitated array of electrodes was patterned over glass, where it was then bonded to a series of fluidic networks created in PDMS via soft lithography. The device measured ethanol impedance initially to show that values remain consistent over time. Impedance values of water and 1% wt. saltwater were compared to show that the device is able to detect changes in impedance, with up to a 60% reduction in electrical impedance in saltwater. Cells were …

Cost-Effective Paper-Based Diagnostic Using Split Proteins To Detect Yeast Infections, Zachary R. Berglund, Kevin V. Solomon, Mohit S. Verma, Moiz Rasheed, Zachary Hartley, Kevin Fitzgerald, Kok Zhi Lee, Janice Chan, Julianne Dejoie, Makayla Schacht, Alex Zavala

The Summer Undergraduate Research Fellowship (SURF) Symposium

The common yeast infection, vulvovaginal candidiasis, affects three out of four women throughout their lifetime and can be spread to their child in the form of oral candidiasis (thrush). This disease is caused by the fungal pathogen Candida albicans, which is also a major cause of systemic candidiasis, a rarer but deadly disease with up to a 49% lethality rate. Current widely-used diagnostic methods include cell cultures, pH tests, and antibody detection, to assist effective treatment. Despite availability of various diagnostic methods, there is no inexpensive, rapid, and accurate way to detect C. albicans infection. This project aims to …