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Mixed-Mode Fracture Analysis Of Additively Manufactured Periodic Orthotropic Functionally Graded Microcellular Materials, Behnam Shahbazian

Theses and Dissertations

The quest for safety, efficiency, and innovation in aerospace engineering demands a relentless focus on understanding how materials and structures behave under extreme and complicated loading conditions. Among the many challenges faced by engineers in this field, predicting and preventing structural failure stands out as both a fundamental necessity and a complex problem. Fracture mechanics, the science of how materials fail under stress, is a cornerstone of this effort. Whether it is the fuselage of an aircraft enduring cyclic loading or the lightweight components of a spacecraft resisting impact, the ability to accurately predict fracture behavior directly influences the reliability …

An Msbe–Driven Advanced Air Mobility Post–Disaster Response System, Olabode A. Olanipekun

Graduate Theses and Dissertations (2019 - present)

In this work, an overarching conceptual design model towards the realization of a proposed Advanced Air Mobility Post–Disaster Response System (AAMPDR system) was explored through the focal lenses of systems thinking (ST), socio–technical systems (STS) and model–based systems engineering (MBSE) paradigms. Initially aimed at providing intervention for casualties and aerial support to emergency rescue workers on the ground in the event of a hurricane disaster around the Gulf shore of the Mobile bay area, Mobile city, AL., the scope of this research subsequently expanded to include a global outlook. Thereafter, culminating in the development of a generalized AAMPDR system model …

The Augmentation Of A Solar Panel Lab For The Chemical Engineering Curriculum To Introduce Sustainability Principles, Lane A. Wilkins

Chemical Engineering Undergraduate Honors Theses

Photovoltaic solar cells are utilized in solar panels to convert sunlight into usable electricity. Since the energy derived from solar panels produces far less greenhouse gas than typical fuels such as coal and natural gas do, it is considered a clean source of energy and is vital to sustainability efforts. Sustainability is often defined by three pillars: environmental, social, and economical. Solar energy incorporates each of these pillars into its process, allowing it to be an effective tool to teach sustainability to students. A previously written lab that employs solar panels focused on the efficiency of converting light into electricity. …

Engaging Future Engineers: Utilizing Ai-Generated Video To Promote The Chemical Engineering Profession, Madeline G. Mondebello

Chemical Engineering Undergraduate Honors Theses

The expected incline of the chemical engineering profession faces a growing need to attract the next generation of prospective students. This research explores the use of artificial intelligence (AI) software to create an innovative form of media fit for secondary school and early college outreach. The pre- and post-video questionnaires were taken by a voluntary population comprised of high school students, college students, and parents. Overall, the feedback received was generally positive but indicated that the AI avatars and the lip-sync discrepancies may disrupt the video more than enhance it. In the future, a larger population will be surveyed to …

Assessing The Fate Of Antibiotic Resistance Genes In Wastewater Treatment Processes, Gunter A. Campbell

Civil Engineering Undergraduate Honors Theses

The increasing need for clean water has paved the way for the creation of systems for reusing water, such as wastewater treatment plants (“WWTPs”), to provide potable water. But in recent years, such systems have raised concerns about the distribution of antibiotic resistance genes (“ARGs”). Bacteria are adapting to antibiotics by the evolution of resistance mechanisms, such as high mutation rates and horizontal transfer. The presence of ARGs, particularly tetracycline ("tetA") resistance genes, in wastewater effluents is of concern, as they can survive treatment, spread to bodies of water, and pose a threat to human health. In this study, the …

A Heuristic Approach To Portrait Segmentation And Its Application To Synthetic Bokeh Generation, Charles J. Snead

Master's Theses

Segmentation of portrait images is an important technique used to separate the foreground and background of an image. This separation of layers is useful for selectively applying post-processing techniques to enhance the quality of the image, such as blurring the background. Automatic portrait segmentation is a complex process that can be completed with a high degree of accuracy using deep learning with neural networks, but training and inference are often very computationally expensive. This thesis aims to take a heuristic approach to portrait segmentation by combining classical image processing and computer vision techniques into a solution that can be run …

Propasafe: A Bert-Based Offline Tool For Propaganda Detection, Vivek Sharma, Mohammad Mahdi Shokri, Shweta Jain, Sarah Ita Levitan, Elena Filatova

Publications and Research

In an era marked by the rapid consumption of digital news, the proliferation of propaganda poses significant threats to democratic values and informed decision-making. We propose a novel framework that prioritizes user privacy while assisting in the automatic detection of propaganda in news articles, allowing users to sift through the rhetoric to read the relevant objective news. As a demonstration of this framework, we present Propasafe, a BERT-based browser extension designed to alert users to propagandist tones in news articles. By highlighting instances of propaganda-like language in real-time, Propasafe empowers users to critically engage with news content, promoting objective understanding …

The Evolution Of Nanoparticles In Nanoparticle Doped Optical Fibers, Mary Cahoon

All Dissertations

Optical fiber and fiber laser technologies based on silica glass are critical to many technologies today. One method to improve the optical performance of laser fibers is engineer the local environment around the active elements in the glass. To that end, this Dissertation focused on the fabrication and characterization of fibers made with nanoparticles incorporated into the glass to control the local composition. First, the nanoparticle composition and structure was analyzed as it evolved from from the initially-synthesized form to incorporation into the dense aluminum-silicate glass. The aluminum oxide in the glass was found to be important not only to …

Development Of Translational Microscale Systems To Interrogate How Biophysical And Biochemical Cues Alter The Phenotype Of Hormone Positive Breast Cancer, Braulio Ortega Quesada

All Dissertations

Cancer is a complicated disease and one in every three diagnoses are women with breast cancer. Recent research shows that the progression of cancer depends strongly on interactions with other non-cancerous cells and non-cellular components. Metastasis, the spread of cancer to other parts of the body, is a key step in cancer progression and makes treatment harder, leading to poor response to treatments culminating in death in ~90% of patients. This dissertation focused on creating a series of microdevices as novel pre-clinical models of breast cancer. Two different devices were fabricated to (1) study how exposing cancer cells to the …

Learning Through Online Participation: From Breakout Rooms To Discord, Makayla Moster

All Dissertations

For software development teams, teamwork is an essential part of their day-to-day lives. However, due to the aftermath of the COVID-19 pandemic, more companies have allowed employees to have more hybrid and remote work options than before. As more companies are adopting hybrid and remote workstyles, we need to ensure that we are preparing the next batch of young software developers to conduct teamwork in remote and hybrid settings. In this dissertation, I address the tools students use for teamwork and how to improve their teamwork inside and outside of the classroom. I present my research on improving student experiences …

Ex Vivo Multiplex Knockdown Of Angptl3 And Cypor In Hepatocytes As A Novel Cell Therapy For Familial Hypercholesterolemia, Callie D. Clark

All Dissertations

Inherited metabolic diseases (IMDs) affect approximately 1 in 800 individuals. The only curative treatment for IMDs is liver transplantation. However, transplantation carries significant risks, including organ rejection and a lifelong need for immunosuppression. Therefore, gene editing has emerged as a promising alternative to liver transplantation for treating IMDs.

Familial hypercholesterolemia (FH) is and IMD characterized by elevated LDL-C levels resulting in premature cardiovascular disease. CRISPR-Cas9-mediated gene editing to disrupt the gene encoding angiopoietin-like 3 (ANGPTL3) in the liver represents a novel therapeutic approach for FH. Nonviral delivery performed ex vivo is safer than systemic delivery because gene editing is in …

Engineering Planktonic And Biofilm Microalgae Systems For Productivity, Power Requirements, Cost, And Scalability, Dallin Chugg

All Graduate Reports and Creative Projects, Fall 2023 to Present

Microalgae cultivation offers dual benefits as an effective wastewater treatment method and a sustainable source of valuable bioproducts, such as biofuels, bioplastics, and feedstocks. This approach supports sustainability by transforming waste into high-value products while minimizing environmental impact. However, scaling microalgae cultivation to industrial levels presents significant challenges, particularly in optimizing harvesting efficiency, reducing mixing and transport costs, and managing large water requirements.

This report compares the productivity, scalability, cost, and energy requirements of two primary cultivation systems: planktonic and biofilm. Planktonic systems, such as open raceway ponds (ORPs), excel in light distribution and nutrient uptake due to continuous mixing, …

Fibrin-Polycaprolactone Scaffolds For The Differentiation Of Human Neural Progenitor Cells Into Dopaminergic Neurons, Salma Paulina Ramirez

Open Access Theses & Dissertations

This project aimed to develop a tissue-on-a-chip platform for studying Parkinson's Disease (PD) using dopaminergic (DA) neurons. PD is a neurodegenerative disorder characterized by progressive loss of DA neurons, leading to involuntary movements and other symptoms. Early diagnosis and deeper understanding of PD pathogenesis are crucial for improving disease management and patient outcomes. To model PD in vitro, this research utilized human-induced pluripotent stem cell (hiPSC)-derived neural progenitor cells (NPCs) cultured on electrospun (ES) polycaprolactone (PCL) scaffolds. Given PCL's hydrophobicity, ECM-based biomaterial coatings, including Cell Basement Membrane (CBM) proteins, Matrigel, and Fibrin, were explored to enhance NPC adhesion, differentiation, and …

Electrodeposition Of Gallium Nitride_Unraveling The Role Of Precursors, Deposition Conditions, And Substrate Effects For Semiconductor Applications, Mauricio Azier Leyva Aranzabal

Open Access Theses & Dissertations

Gallium nitride (GaN) is a wide-bandgap semiconductor noted for its remarkable optoelectronic and structural characteristics, rendering it a potential material for high-power, high-frequency, and optoelectronic device applications. This dissertation investigates the electrochemical synthesis of GaN thin films by potentiostatic and galvanostatic electrodeposition techniques using aqueous solutions of gallium nitrate (Ga(NO3)3), ammonium nitrate (NH4NO3), and auxiliary agents like potassium nitrate and urea. The main aim is to examine the essential elements affecting nitrogen incorporation and film shape while assessing electrochemical performance on various conductive substrates.A thorough investigation was performed to evaluate the impacts of electrodeposition duration, electrolyte pH, precursor molar concentrations, …

Tailoring Functional And Sensing Properties Of Polymer-Ceramic Composites Via 3d Printing, Alexis Lopez

Open Access Theses & Dissertations

Section 1.1. Abstract This chapter investigates the use of direct ink write (DIW) additive manufacturing to control grain orientation in non-toxic barium titanate (BTO) ceramics by blending spherical and platelet-shaped particles in the ink. A series of inks containing 0–40 wt.% BTO platelets were formulated with poly(vinyl alcohol), polyethylene glycol, poly(acrylic acid-co-maleic acid), and ammonium hydroxide to ensure printability and homogeneous dispersion. Cylindrical specimens (20 mm × 3 mm) were printed using a Hyrel 30M DIW system and subjected to de-binding (650 °C, 2 h) followed by a two-step sintering schedule (T₁: 1200–1350 °C; T₂: 700–850 °C; 24 h dwell). …

Involvement Of Long Non-Coding Rna (Lncrna) Malat1 In Shear Stress Regulated Adipocyte Differentiation, Justin Caron, Marjan Ghanbariabdolmaleki, Madison Marino, Chong Qiu, Bo Wang, Michael Mak, Shue Wang

Biomedical Engineering Faculty Research and Publications

Adipocyte differentiation plays an important role in bone remodeling due to secretory factors that can directly modulate osteoblast and osteoclast, thus affecting overall bone mass and skeletal integrity. Excessive adipocyte differentiation within the bone marrow microenvironment can lead to decreased bone mass, eventually causing osteoporosis. The mechanical microenvironment of bone marrow, including fluid shear, maintains the balance of adipocyte and osteoblast differentiation during bone remodeling. However, how mechanical cues interact with long noncoding RNA (lncRNA) and regulate adipocyte differentiation remains unexplored. In this study, we investigated the mechanosensitive role of lncRNA MALAT1 during mesenchymal stem cells (MSCs) adipocyte differentiation. By …

In Vitro Investigation Of Macrophage Functional And Metabolic Modulation, Shelby Nicole Bess

Graduate Theses and Dissertations

Macrophages are a subset of immune cells with a variety of functions that are abundant in numerous tumor types such as colorectal and breast cancer. It has been suggested that macrophages may serve an important function as immune mediators in tumor behavior; however, macrophage activity is complex and remains not completely understood. The overall goal of this dissertation was to explore and exploit tumor-associated macrophage phagocytic function and the changes in their interactions with cancer cells in an in vitro mouse model and in 2D and 3D in vitro culture models. First, we wanted to better understand macrophage behavior under …

Vision-Based Multimodal Frameworks For Human Behavioral Analysis: Applications In Group Activity Understanding And Public Health, Naga Venkata Sai Raviteja Chappa

Graduate Theses and Dissertations

Group Activity Recognition (GAR) has emerged as a crucial problem in computer vision, with wide-ranging applications in sports analysis, video surveillance, and social scene understanding. Unlike traditional action recognition focused on individuals, GAR requires understanding complex spatiotemporal relationships between multiple actors, their interactions, and the broader context in which these activities occur. This complexity introduces unique challenges, including the need for accurate actor localization, modeling of inter-actor dependencies, and understanding of temporal evolution in group behaviors. While recent advances have shown promise, existing approaches often rely heavily on extensive annotations such as ground-truth bounding boxes and action labels, creating significant …

Investigating The Effects Of Hepatocyte Growth Factor On Primary Myoblast Proliferation, Grace Heller

Biomedical Engineering

Peripheral artery occlusive disease (PAOD) is a progressive vascular condition that affects over 200 million people worldwide and approximately 8 million in the United States. It is characterized by atherosclerotic narrowing of peripheral arteries, leading to reduced blood flow, ischemia, and, in severe cases, tissue loss and limb amputation. Although surgical revascularization is the gold standard, many patients—particularly those with comorbidities like diabetes— continue to experience poor outcomes, emphasizing the need for alternative therapies. One promising strategy is to enhance collateral arteriogenesis, the remodeling and enlargement of collateral arterioles that naturally bypass occluded vessels. Satellite cells (SCs), which give rise …

The Effects Of Cigarette Smoke Extract On Osteoarthritis In A Primary Joint Tissue Explant Model, Emily Sawvell

All Dissertations

Osteoarthritis (OA) is the most common degenerative joint disease in the world with an economic burden of nearly $140 billion annually. Factors identified to increase the risk of developing OA include age, obesity, sex, race, genetics, and previous joint injury. However, one risk factor that has been scarcely studied in OA etiology is cigarette smoking. While some studies have reported smoking to protect against OA, increasing evidence suggests that cigarette smoking results in more severe and painful OA, increases the rate of developing OA, and reduces the efficacy of pain medications and arthritis-targeting therapies. Despite this, the impact of cigarette …

Understanding Dimensional Stability Of Polymer Surgical Mesh, Simeon J. Mckelvey

All Dissertations

Polymer surgical mesh is a biomedical implant that has revolutionized the repair of the abdominal wall and pelvic floor. Each year, over 1.6 million Americans undergo surgical procedures using polymer surgical mesh to treat conditions where internal organs protrude through weakened tissues. This material is used in approximately 90% of hernia repairs, 80% of stress urinary incontinence procedures, and 30% of pelvic organ prolapse surgeries.

Despite this widespread use of polymer surgical mesh, post-implantation complications have prompted regulatory investigation and scrutiny. These complications stem from the mesh's behavior within the human body, including wrinkling, contraction, and loss of fixation, which …

Ceramic Membrane Evaluation Via Automated Filtration Systems For Water Treatment And Resource Recovery, Weiming Qi

All Dissertations

Membranes are an advanced and mature water and wastewater treatment technology. Membrane fouling is a key difficulty for all membrane filtration processes, leading to significant attention in the literature over the years. A common problem in laboratory-scale membrane research is that the testing methods in the laboratory are often quite different than industrial applications due to the limitations of manual experimental setups. An automated membrane filtration apparatus was built in the lab to solve this problem by allowing long-term filtration, frequent backwash and CIP, and high-accuracy operation. The filtration system achieves different cleaning strategies for both theoretical research and practical …

Computationally Guided Liquid Crystal-Based Competitive Binding Sensing Platform For Optical Detection Of Spike Protein, Homa Ghaiedi, Shubham Pandey, Sophia Ezendu, Tibor Szilvasi, Karthik Nayani

Chemical Engineering Faculty Publications and Presentations

A liquid crystal (LC)-based sensing platform for the rapid optical detection of SARS-CoV-2 ' s spike protein's receptor binding domain (RBD) domain is introduced. This platform utilizes a thermotropic LC, hosted on metal-cation decorated substrates, onto which the spike protein can competitively bind. Density functional theory (DFT) calculations guide the experiments that reveal a homeotropic-to-planar transition in the LCs upon exposure to SARS-CoV-2 spike-decorated yeast, providing a basis for sensitive virus detection. The sensor's reversibility/specificity is confirmed through antibody-induced orientation recovery of the LCs initial orientation. Strikingly, the sensor can detect approximate to 2000 copies of the spike protein per …

Towards Explainable And Robust Nlp: Neutrosophic Probability Augmentation In Text Classification, Nabil M. Abdel-Aziz, Mahmoud Ibrahim, Khalid A. Eldrandaly

Neutrosophic Systems with Applications

The rapid growth of textual data necessitates advanced text classification models. However, traditional methods struggle with ambiguity and uncertainty in natural language, reducing classification reliability. To address this, we integrate neutrosophic logic, which explicitly models truth, indeterminacy, and falsity, into a DistilBERT-based text classification framework. Additionally, we employ data augmentation using synonym replacement to enhance generalization. Our approach is evaluated on the AG News dataset, classifying articles into four categories: World, Sports, Business, and Science/Technology. By incorporating neutrosophic attributes, the proposed framework assesses text quality, mitigates uncertainty, and improves robustness against ambiguous inputs. Experimental results demonstrate an accuracy of 94.10%, …

Locked Dimerized Cxcl12 Exerts Radiosensitizing Effects In Head And Neck Cancer, Oscar Villarreal Espinosa, Musaddiq Awan, Abdullah A. Memon, Anne Frei, Jamie Foeckler, Rachel Kuehn, Jennifer Bruening, Becky Massey, Stuart J. Wong, Monica Shukla, Julia Kasprzak, Amit Joshi, Michael B. Dwinell, Heather A. Himburg, Joseph Zenga

Biomedical Engineering Faculty Research and Publications

Background

Head and neck squamous cell carcinoma (HNSCC) presents significant treatment challenges, particularly in cases unrelated to human papillomavirus (HPV). The chemokine receptor CXCR4, interacting with its ligand CXCL12, plays a crucial role in tumor proliferation, metastasis, and treatment resistance. This study explores the therapeutic potential of engineered monomeric and dimerized CXCL12 variants (CXCL121 and CXCL122, respectively) in HNSCC and evaluates potential additive effects when combined with radiation therapy.

Methods

Clinical HNSCC biopsies were evaluated for CXCR4 expression in both previously untreated and radiorecurrent disease. HNSCC cell lines were then treated with combinations of CXCL12 variants and radiotherapy and interrogated …

Air And Missile Defense Threat Scenario Variation To Reduce Pretest Sensitization, Video Games As A Case Study, Julie Renee Szekerczes

All-Inclusive List of Electronic Theses and Dissertations

This study uses fixed and variable video game types to measure pretest sensitization as a proxy for repeated and varied threat test scenarios in system performance testing of air and missile defense systems. The pretest sensitization phenomenon exists when repeated exposure to a test condition influences the participant's response. Research shows air and missile defense development correlates with video games, resulting in similar interfaces and computer operating environments. Department of Defense acquisition test and evaluation results must reflect system performance without prior knowledge of the threat scenarios confounding the results. System performance results inform acquisition decisions, such as further funding …

Effects Of Different Blue Light Conditions On Saos-2 Cell Viability, Differentiation, And Mineralization, Jamielyn Alcantara Jarvis

Theses and Dissertations

Photobiomodulation (PBM) is a low-intensity light therapy that uses non-ionizing forms of energy to induce a directed cellular response. Prior work has investigated the effects of blue light exposure at energy densities ranging from 1 J/cm2 to 10 J/cm2 on osteogenic differentiation of human gingival mesenchymal stem cells (hGMSCs), human dental pulp stem cells (hDPSCs), and stem cells from the apical papilla (SCAPs) and shown promising outcomes at 4 J/cm2 and then having a detrimental impact at higher energy densities. One key caveat in prior studies is that the blue light energy density was modulated by changing the light exposure …

Experimental And Theoretical Fracture Analysis Of Rift Manufactured Carbon Fiber-Vinyl Ester Lamina, Daniel Joseph Longo

Theses and Dissertations

This thesis investigates the fracture behavior of unidirectional carbon fiber-vinyl ester (CFVE) laminates manufactured using the Resin Infusion with Flexible Tooling (RIFT) process, a cost-effective alternative to autoclave-based fabrication methods. Composite materials like CFVE are increasingly adopted in high-performance applications due to their high strength-to-weight ratio and corrosion resistance; however, their anisotropic nature presents challenges in predicting crack initiation and propagation. To address this, a comprehensive approach combining experimental testing, finite element modeling (FEM), and classical fracture mechanics was employed. Orthotropic mechanical properties were first determined through tensile and shear tests, providing critical properties for FEM simulations. A series of …

Cross-Dataset Fairness Evaluation Of Transformer-Based Sentiment Models, Sara Zuiran

Theses and Dissertations

With the growing exploration of Natural Language Processing (NLP) systems in decision-making environments, it is essential to evaluate technical and ethical aspects of the dataset and the NLP model to improve fairness. To assess fairness, the thesis examines demographic imbalances in sentiment classification models by evaluating transformer-based models fine-tuned on the Stanford Sentiment Treebank version 2 dataset (SST-2) against the demographically annotated Comprehensive Assessment of Language Model dataset (CALM). This work identifies performance disparities in sentiment prediction across demographic groups by examining sensitive attributes such as gender and race. The study evaluates both the RoBERTa and MentalBERT transformer models using …

The Effect Of A Peptide Targeting Ligand On Transfection Efficiency Of Polymeric Nanoparticles To Dendritic Cells, Anthony Radka

Honors Theses

Autoimmune diseases affect approximately 5-8% of the global population, leading to chronic symptoms, long-term treatment, and reduced quality of life. Current therapies primarily rely on lifelong administration of immunosuppressants, which are associated with severe side effects and heightened susceptibility to infections. This has spurred interest in cellular therapies that manipulate dendritic cells (DCs) effectively and can selectively treat these diseases. This work aims to improve the efficacy of dendritic cell-based therapies using cationic polymers that can electrostatically complex with nucleic acids, forming nanoparticles referred to as polyplexes, that can deliver therapeutic nucleic acid cargo. These particles are a favorable alternative …