Engineering Commons^™

Assessment Of Material Properties In Bone Surrounding Microdamage, Niovi Dollas

Dissertations and Theses

Bisphosphonates [BPs] are the mainstay for osteoporosis treatment. They suppress bone resorption/remodeling, preventing bone loss. However, BPs also suppress the beneficial bone remodeling that replaces microscopically damaged bone that occurs from normal mechanical wear-and-tear or fatigue, leading to impaired tissue material properties and in some instances atypical femoral fractures.

In these studies, we assessed the effects of acute fatigue, fatigue induced remodeling, and fatigue microdamage with remodeling suppression using the clinical BP, alendronate [ALN], on local bone material properties. Studies were performed on cortical bone sections from rat ulnae into which fatigue damage had been introduced in vivo. Rat …

Use Of Bioheat Modeling To Characterize And Optimize Implantable Medical Devices And Neuromodulation Technologies, Adantchede Louis Zannou

Dissertations and Theses

Medical device development includes prototyping, benchtop characterization, preclinical studies, and clinical trials. Understanding the limitations and potential adverse effects of medical devices prior to their administration in humans is a crucial first step. Optimizing medical devices is essential to employing technology and improving patients care. Computational modeling is widely adopted as a powerful tool to predict stimulation/recording parameter optimization, rapid electrode/device prototyping, investigating novel mechanism of action, and testing working principles of any medical devices. Many implantable neuromodulation technologies including Spinal Cord Stimulation (SCS), which provide substantial therapeutic benefit for patient population with lower back pain, produces heat via the …

Tdcs Effects On Synaptic Plasticity And Motor Skill Learning, Forouzan Vasheghani Farahani

Dissertations and Theses

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that involves the application of low-intensity constant current to the brain through electrodes placed on the scalp. Its potential to enhance brain function and treat brain-related disorders has led to its increasing popularity due to its safety, simplicity, and affordability. However, its effectiveness remains a topic of debate.

Mechanically Driven In Vivo Osteocyte Ca2+ Signaling: Aging And Pharmacologic Effects, James Padgett

Dissertations and Theses

Bone’s ability to respond and adapt to mechanical loading declines significantly with age which is a major contributor to bone fragility. It is widely accepted that osteocytes are the key cells responsible for orchestrating the development of the “ideal” skeleton. This ability is attributed to osteocyte’s role as the primary mechanosensing cell that is responsible for maintaining the skeleton’s integrity throughout life. Recent work from our laboratory has shed light into how osteocytes respond to mechanical loading in vivo. The breakthrough approaches that enabled these discoveries were development of: (1) the first ever reporter mouse model with a genetically encoded …

Optimization Of Optical Nanosensor Response For The Detection Of Anthracyclines Using A Binary Machine Learning Classifier, Myesha Thahsin

Dissertations and Theses

Pharmacokinetic variables such as interindividual variation in metabolizing and eliminating drugs makes dose selection of chemotherapeutic anthracyclines difficult. One potential solution to determining dosing levels of an anthracycline is the development of non-invasive sensors to monitor their pharmacology in vivo. Single-walled carbon nanotubes (SWCNT) have substantial potential for in vivo sensor development, as they exhibit near-infrared fluorescence in the tissue-transparent window and a robust response to their local environment. An emerging method for evaluating and optimizing SWCNT sensor response is through machine learning. In this study, anthracyclines Daunorubicin, Doxorubicin, Epirubicin, Mitoxantrone and Idarubicin, were used to interrogate 12 SWCNT preparations …

Ultra-High Field Mri Methods For Precise Anatomical And Spectroscopic Measurements In The Brain And Application To Neurological And Neuropsychiatric Diseases, Judy Alper

Dissertations and Theses

Neurological and neuropsychiatric diseases and disorders are a major burden on society, impairing the health and functioning of millions of people every year. There is a need to define the biological bases of these diseases and identify potential biomarkers to improve diagnosis, monitoring, and treatment efficacy across multiple diseases.

Magnetic resonance imaging (MRI) is a noninvasive imaging technique which facilitates detection of brain lesions and visualization of the brain overall. However, limitations in contrast and resolution at clinical field strengths may hinder investigation of the underlying biological mechanisms of these diseases. Ultra-high field MRI scanners, such as those at 7-Tesla, …

Material Characterization Of Thermoplastic Polyurethane (Tpu) And Thermoplastic Elastomers (Tpe) For Development Of 3d-Printed Surrogate Organs For Medical Training, Anastasia Elizabeth Lucci

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cadaveric specimens are a necessary, albeit limited, resource for training medical students on basic surgical skills. The availability of surrogate 3D-printed organs would readily allow access to resources that could reduce or potentially eliminate the need for cadaveric specimens or, at a minimum, provide students the opportunity to practice with 3D-printed surrogates before transitioning to those specimens. This research focuses on determining which thermoplastic material most closely mimics mechanical properties such as hardness and stiffness of human organs and allows 3D printing surrogate organs to be used as safe, educational tools. Relatively “soft” materials such as thermoplastic polyurethanes (TPU) and …

Breast Density Classification Using Deep Learning, Conrad Thomas Testagrose

UNF Graduate Theses and Dissertations

Breast density screenings are an accepted means to determine a patient's predisposed risk of breast cancer development. Although the direct correlation is not fully understood, breast cancer risk increases with higher levels of mammographic breast density. Radiologists visually assess a patient's breast density using mammogram images and assign a density score based on four breast density categories outlined by the Breast Imaging and Reporting Data Systems (BI-RADS). There have been efforts to develop automated tools that assist radiologists with increasing workloads and to help reduce the intra- and inter-rater variability between radiologists. In this thesis, I explored two deep-learning-based approaches …

Modeling The Production Of Microalgal Biomass In Large Water Resource Recovery Facilities And Its Processing Into Various Commodity Bioproducts, James Pierson, Gopi Raju Makkena, Sandeep Kumar, Vinod Kumar, Vivekanand Vivekanand, Hasan Husain, Muhammad Ayser, Venkatesh Balan

Civil & Environmental Engineering Faculty Publications

Algae are capable of sequestering nutrients such as nitrates and phosphates from wastewater in the presence of sunlight and carbon dioxide (CO₂) to build up their body mass and help combat climate change. In the current study, we carried out different case studies to estimate the volume of algal biomass that could be produced annually using the rotating algal biofilm (RAB) method in three large-scale water resource recovery facilities (WRRFs) in Texas: Fort Worth, Dallas, and Houston. We calculated the total amount of lipids, carbohydrates, and proteins that could be fractionated from the algal biomass while using the …

Analyzing Physiological Signals During The Menstrual Cycle: Introducing An Application Of Circular Statistics, Krystal D. Sides

UNF Graduate Theses and Dissertations

Physiological signals are used in engineering and the sciences to determine the state of functionality of certain physiological systems such as the human endometrium. Many women use the basal body temperature method to track ovulation, or their fertile window. However, temperature tracking alone is subject to environmental factors. Non-invasive wearable devices can be tools in recording cycle-related physiological features relevant to women’s health research. This research uses the Empatica E4 wristband to track changes in the physiological features during sleep across the menstrual cycle of ovulating and non-ovulating females. Due to the cyclic nature of menstrual cycles, analytic solutions to …

Mechanical Design Of A Microwave Imaging Device For Breast Cancer Detection In Mri Scanners, Grace M. Player

Dartmouth College Master’s Theses

This project seeks to develop an updated version of a microwave imaging device for use in conjunction with breast MRI, improving upon existing technology and developing novel concepts for the device. It posits three primary redesign targets for updating the previous system: resizing the system height, making the device more iteration- friendly, and improving the overall manufacturability of the device by replacing custom components with commercially available alternatives. All three of these redesign targets are met in the new design, V2.0. The height is reduced by reducing antenna travel and height, embedding some components, and shortening the tank wall, resulting …

Leveraging Cell-Substrate Adhesion And Cell Migratory Properties In Skeletal Muscle Constructs And Cancer Metastasis Assays, Lauren E. Mehanna

Theses and Dissertations--Chemical and Materials Engineering

Volumetric muscle loss (VML) remains one of the few skeletal muscle injuries without a reliable and repeatable treatment. In large volume muscle injuries, muscle fibers as well as the surrounding connective tissue are damaged, preventing therapeutic muscle stem cells, called myogenic progenitor cells (MPCs), from reaching the injury site and initiating repair. There is a clinical need to rapidly fabricate in vitro muscle tissue constructs that mimic the native tissue organization, with aligned myotubes, for insertion and integration at the patient’s injury site. In this dissertation, we utilize the MPC’s natural propensity to close gaps across an injury site to …

Identification Of Proteins Involved In Cell Membrane Permeabilization By Nanosecond Electric Pulses (Nsep), Giedre Silkuniene, Uma Mangalanathan, Alessandra Rossi, Peter A. Mollica, Andrei G. Pakhomov, Olga N. Pakhomova

Bioelectrics Publications

The study was aimed at identifying endogenous proteins which assist or impede the permeabilized state in the cell membrane disrupted by nsEP (20 or 40 pulses, 300 ns width, 7 kV/cm). We employed a LentiArray CRISPR library to generate knockouts (KOs) of 316 genes encoding for membrane proteins in U937 human monocytes stably expressing Cas9 nuclease. The extent of membrane permeabilization by nsEP was measured by the uptake of Yo-Pro-1 (YP) dye and compared to sham-exposed KOs and control cells transduced with a non-targeting (scrambled) gRNA. Only two KOs, for SCNN1A and CLCA1 genes, showed a statistically significant reduction in …

Biom 4760: Biomedical Engineering Design Principles (Syllabus), Carl D. Herickhoff

Biomedical Engineering Syllabi Archive

Course Description: Practical design methods emphasizing the front-end or concept development stage of engineering design; design a system, component, or process to meet desired needs within realistic constraints with functioning on multi-disciplinary teams.

Biom 3110(Honors): Medical Physiology (Syllabus), Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Basic principles of human physiology and how these are applied in medicine and biomedical engineering problem and devices; physiological principles using appropriate mathematical and engineering models to construct an understanding of how the body works as an integrated system.

Biom 1720: Introduction To Biomedical Engineering Tools (Syllabus), Stephen Strain

Biomedical Engineering Syllabi Archive

Course Description: Use of computer tools for data analysis, presentation, documentation; introduction to programming; individual and group design projects.

Biom 2720: Experimental Design And Analysis For Biomedical Engineering (Syllabus), Stephen Strain

Biomedical Engineering Syllabi Archive

Course Description: Application of probability, statistics, error analysis, uncertainty in design and performance of biomedical engineering experimentation; discussion and evaluation of common experimental designs for medical device development.

Engr 1009: Preparation For Engineering Problem Solving (Syllabus), Stephen Strain

Biomedical Engineering Syllabi Archive

Course Description: Applications of algebra and trigonometry to engineering problems. Accelerated preparation for an engineering or technology major.

The Wound Healing And Antibacterial Properties Of Mesenchymal Stromal Cell Extracellular Matrix Nanoparticles, Emily N. Wandling

Theses and Dissertations

Treatments for acute respiratory distress syndrome (ARDS) are still unavailable and the prevalence of the disease has only increased due to the Covid-19 pandemic. Mechanical ventilation regiments are still utilized to support declining lung function, but they also contribute to lung damage and increase the risk of bacterial infection. The anti-inflammatory and pro-regenerative abilities of mesenchymal stromal cells (MSCs) have shown to be a promising therapy for ARDS. We propose to utilize the regenerative effects of MSC secretome and the extracellular matrix (ECM) into a nanoparticle. Our mouse MSC (MMSC) ECM nanoparticles were characterized using size, zeta-potential, and mass spectrometry …

Investigating Tgf-Β1 And Fibronectin Signaling In Low Oxygen Environments, Caitlin E. Williams

Theses and Dissertations

Breast cancer is the second leading cause of death in women, second to lung cancer. It’s one of the most well-known cancers, with almost 300,000 new cases estimated to be diagnosed in 2023. Breast cancer often begins in ductal epithelial cells, and these cells will typically undergo a cellular transformation process known as epithelial-mesenchymal transition (EMT) in early stages. Breast cancer becomes deadly when it reaches a metastatic stage. As a part of the metastatic process, transformed cells will conduct remodeling of the extracellular matrix (ECM) to allow for migration of an otherwise non-migratory cell type.

As dense tumors form, …

Experimental Evaluation Of Micro-Epidermal Actuators On Flexible Substrates, Courtney D. Bradley

Graduate Research Theses & Dissertations

Does embedding actuators in a flexible substrate increase their performance in hearing aids? What are the differences in damping experienced by actuators of different diameters and at different locations? At what frequency is peak acceleration achieved and what role does the size of the actuator and embedding it in a flexible substrate play? These questions will form the basis of this thesis. This work was done to develop a small non-invasive Band-Aid-©-like hearing aid. The novelty of this device requires a detailed analysis of piezoelectric actuators. This is a continuation of past students’ work on the topic. The main parameters …

Surface Modified Titanium And Doxycycline Loaded Pcl/Plga Nanofibers For Improved Cellular Interaction And Biocompatability, Dexter D. Kling

Graduate Research Theses & Dissertations

Biomaterials play an important role in modern medicine through their complexfunctionalities, as implants, grafts, and drug delivery systems. The addition of dopants and biomolecules in biomaterials offers unique solutions to common issues and provides new methods of improving overall health. In our work, we examined osteoblast cell interactions with titanium (Ti) after alkali treatment and deposition of magnesium (Mg) and iron (Fe). We also studied the antibacterial properties of doxycycline loaded polymeric nanofibers produced via electrospinning. To study the biological properties of surface-modified Ti, we first prepared commercially pure titanium samples by grinding and polishing, then performed alkali treatment in …

Reconfigurable Microfluidic Circuits Through Modular Surface Driven Microfluidic Diode Valves, Selina Cervantes

Graduate Research Theses & Dissertations

In this thesis, we explore the rapidly evolving landscape of healthcare and diagnostics, shaped by the transformative impact of the COVID-19 pandemic. The focus of Point-of-care showcases innovative breakthroughs in microfluidics, capillary action, and lateral flow technology that are revolutionizing medical diagnostics. We delve into the mechanics of current assays, particularly in resource-limited settings. We then unveiled the introduction of a novel fluidic diode valve, designed to enhance lateral flow assays (LFAs) for point-of-care diagnostics. This diode design boasts a unidirectional flow mechanism, and our proof-of-concept experiments validate its potential for scalability, precise flow control, and applications in complex lateral …

Studying And Troubleshooting Lubricity Test On Pressure Wire X Proximal And Distal Coatings, Usama A. Khan

All Graduate Theses, Dissertations, and Other Capstone Projects

Coatings of guidewires used in medical device manufacturing industry are one of the most important element aspects. It defines its efficiency to penetrate through tightest of canals and curves. Guidewires are put through controlled environment to accelerate its age and tested for its mechanical features. Pressure Wire X failed the lubricity testing after being tested by multiple operators and at alternate sites. A cause-and-effect diagram shows all potential causes of test failure. The human factor involved in the test failure was investigated through multiple Gage R&R and training records. Calibration error with the lubricity tester DL1000 was identified and solved …

Finite Element Analysis Of 3d-Printed Pcl Scaffolds, Ireolu K. Orenuga, Joao Soares, Phillip D. Glass, Daeha Joung Ph.D.

UROP Posters

Finite Element Analysis of 3D-printed PCL Scaffolds for Synergizing Cellular Micro-Environment and Mechanical Stimuli to Enhance Engineered Tissue Growth in Vitro

Ireolu Orenuga,1 Phillip Glass,2 Daeha Joung,2 Joao S. Soares1

1. Department of Mechanical and Nuclear Engineering, College of Engineering, Virginia Commonwealth University
2. Department of Physics, College of Humanities & Sciences, Virginia Commonwealth University

Introduction: Tissue engineering aims to create viable and functional engineered tissues via biodegradable scaffolds and autologous cells. Scaffolds play an essential part in organizing the architecture of developing tissues and aid in the proper function of implants acutely by serving as mechanical support and long-term by …

Differential Gene Expression Analysis Of Rodent Mammary Tissue Reveals Dysregulation Of Greb1 And An Age-Dependent Response To Spaceflight, Cleoma Arnold

Master's Projects

Life aboard spacecraft poses a danger to astronaut health, with hazards including microgravity, radiation, and enclosed spaces. Research into mitigating these health issues includes analysis of the transcriptome of rodents sent to the International Space Station. This project investigates the effects of spaceflight on the mammary tissue of female mice of two age groups, 10-12 and 32 weeks, in order to assess the impact of age and spaceflight on gene expression in a tissue relevant to female health. Analysis of the OSD-511 dataset from NASA’s Open Science Data Repository utilized a containerized implementation of their RNA-Seq pipeline on the San …

Ultrasensitive Tapered Optical Fiber Refractive Index, Erem Ujah, Meimei Lai, Gymama Slaughter

Electrical & Computer Engineering Faculty Publications

Refractive index (RI) sensors are of great interest for label-free optical biosensing. A tapered optical fiber (TOF) RI sensor with micron-sized waist diameters can dramatically enhance sensor sensitivity by reducing the mode volume over a long distance. Here, a simple and fast method is used to fabricate highly sensitive refractive index sensors based on localized surface plasmon resonance (LSPR). Two TOFs (l = 5 mm) with waist diameters of 5 µm and 12 µm demonstrated sensitivity enhancement at λ = 1559 nm for glucose sensing (5-45 wt%) at room temperature. The optical power transmission decreased with increasing glucose concentration due …

Integrated Multi-Omics Analysis Of Gut Microbiome And Host Transcriptome To Identify Novel Biomarkers For Hepatocellular Carcinoma, Jakkrit Khamjerm

Chulalongkorn University Theses and Dissertations (Chula ETD)

An imbalance in gut microbiome is strongly linked to liver inflammation disease and hepatocellular carcinoma (HCC) via the gut-liver axis. However, the understanding of how gut microbiota interacts with the host gene expression is still limited. In this study, we aim to investigate the relationship between gut microbiome profile and transcriptomic profile in patients with HCC. In this study, 17 patients with viral-related HCC, 13 non-viral-related HCC, and 10 healthy controls were recruited. We investigated gut microbiome profile from fecal samples using 16S rRNA sequencing and host transcriptomic profile from the peripheral blood mononuclear cells (PBMCs) using RNA sequencing method. …

Radiomics-Based Prediction Of Radiation-Induced Hypothyroidism In Nasopharyngeal Cancer Patients, Napat Ritlumlert

Chulalongkorn University Theses and Dissertations (Chula ETD)

When planning radiation therapy, late-effect complications due to radiotherapy should be considered. One of the most common complications of head and neck radiotherapy is hypothyroidism. Although clinical and dosimetry data are usually used to assess the risk of hypothyroidism after radiation for nasopharyngeal cancer, the outcome is still unsatisfactory. Medical imaging can provide additional information and increase prediction accuracy. The aim of this study was to predict hypothyroidism in patients with nasopharyngeal cancer using CT radiomics combined with clinical and dosimetric data. The study included 220 participants who were diagnosed with hypothyroidism within 2 years after radiotherapy. Manual segmentation covered …

Development Of Molecular Imprinted Polymer Coated Single Mode-Multi Mode-Single Mode Optical Fiber Sensor For Diabetes Voc Biomarker Detection, Pannathorn Jitpratak

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work demonstrates a molecular imprinted polymer (MIP) coated optical fiber sensor for volatile organic compounds (VOCs) which is a biomarker for non-invasive diabetes diagnosis by using patient’s breath as a sample. MIP template is acetone, ethanol, and isopropanol on purpose to target these VOCs for the detection due to the ability of specific binding site in the cavity of polymer matrix achieved from template removal. A MIP coated multi-mode fiber (MMF) connected to single mode fiber (SMF) at both ends to achieve MIP coated SMS structure on purpose to enhance sensitivity due to the evanescent field emitting from MMF …