Digital Commons Network^™

Detecting Flowering Coverage In North Dakota Right-Of-Ways For Supporting Pollinators: A Road Survey Approach, Yeqian Xu

Theses and Dissertations

Establishing and maintaining high-quality grasslands and conservation lands for pollinators can be difficult and costly. As an alternative, roadsides can provide additional forage resources. This study aims to examine the potential of roadside, road ditch, and right-of-way (ROW) land in North Dakota (ND) as alternative habitats for pollinators by quantifying the yellow flowering observed in these sites. The project encompasses a multifaceted approach to assess the viability of roadside ditches in supporting pollinator ecosystems. The research incorporates two essential components: 1) an extensive road survey through the Prairie Pothole Region (PPR) of ND in two consecutive summer seasons and 2) …

Exploring Graph Neural Networks In Reinforcement Learning: A Comparative Study On Architectures For Locomotion Tasks, Gaukhar Nurbek

Theses and Dissertations

Deep Reinforcement learning (DRL) has gained importance in optimizing control policies, while Graph Neural Networks (GNNs) offer a robust approach for modeling complex relationships within systems represented as graphs. This thesis investigates the integration of DRL and GNNs to optimize control policies for robotic tasks, with a focus on locomotion. It compares static and dynamic GNN architectures for control policy predictions, revealing their strengths and limitations in adapting to locomotion predictions. The study assesses the impact of model structure complexity on GNNs' predictive capabilities, showcasing how intricate model structure can maximize GNNs' potential in capturing spatial and relational dependencies when …

Examining Time Spent On Social Media And Its Effects On Mental Health In Terms Of Body Image Concerns, Self Esteem And Overall Quality Of Life Among U.S. Adults, Rigel Macarena Pinon

Theses and Dissertations

Daily exposure and dependence on computer-based technologies (smartphones) allows for 24/7 constant access to social media (i.e., Facebook, Instagram, Twitter, YouTube, TikTok, and other sites) and has empirically shown to have a positive and negative impact on the mental health of individuals across cultures in our society. Depending on user intent, exposure, and interests, social media platforms can create a sense of community; however, some of the platforms and what users post about themselves has led to cyberbullying, low self-esteem, user addiction, suicide, self-harm behaviors such as eating disorders, sexual dysfunction, and other mental health issues such as depression and …

An Exploratory Case Study Of Students’ Blended Learning Experiences During Post Emergency Learning, Heidy M. Garcia Moreno

Theses and Dissertations

The COVID-19 pandemic has accelerated the integration of technology in classrooms. This has highlighted the need for a deeper understanding of how students experience these learning environments. In response, this case study explored how students experience blended learning in post emergency learning through a digital equity lens. The analysis of interview data revealed six major themes, which yielded three key findings. These findings emphasize the need to embrace a simplified approach to technology integration, refine instructional practices to effectively use technology as a supplement rather than a replacement for traditional tactile elements, while also advancing digital literacy that builds high …

Photo-Carbon Monoxide Releasing Molecules For Antibacterial Benefits In Vascular Grafts, Beste Caner

Theses and Dissertations

Globally, the annual hemodialysis procedures surpass 1.5 million, emphasizing the vital role of reliable vascular access methods. However, common challenges like access infections and clot-induced blood flow reduction necessitate innovative solutions. This study delved into the potential therapeutic role of carbon monoxide (CO) and its effects on both endothelialization and non-pathogenic bacteria causing infections. The primary focus was evaluating the impact of loading different concentrations of carbon monoxide-releasing molecules (CORMs), specifically CORM diketone 4 (DK4), within 2D spin-coated films on cultured E. coli and endothelial cells. Initial assessments of CO release kinetics from DK4-loaded films demonstrated that the 10% condition …

Modelling Terrestrial And Potential Extraterrestrial Photopigments Via Density Functional Theory, Dorothea Illner

Theses and Dissertations

In the search for extraterrestrial life, biosignatures play a crucial role in identifying its putative traces. A commonly known and robust biosignature is the Vegetation Red Edge (VRE), which can be described as a sharp increase of reflectance observed from a planet and stems from the light absorption of photopigments in specific regions in the electromagnetic spectrum. For Earth, this VRE is known to occur around 700 nm, however, if the photopigments absorb light in different regions and have different structures the VRE could experience a wavelenght shift.

In this work, Chlorophyll a and a potential photopigment precursor called Phot0 …

Investigating Endothelial Damage During Ischemic Stroke Treatment Using In Vitro And Computational Models, Zackary Lorton

Theses and Dissertations

Large vessel occlusion during acute ischemic strokes requires mechanical thrombectomy (MT) procedures using stent retrievers (SR). However, complete clot removal typically takes several attempts, which can amplify endothelial cell injury (EI). This project aims to characterize the extent of EI during MT using an in vitro vascular platform and a finite-element model (FEM). Impact of SR diameter and characterization of SR mechanical forces are assessed and correlated with human umbilical vein endothelial cell (HUVEC) response. HUVECs were seeded on fibronectin (4 µg/cm²) coated true-scale PDMS arterial phantoms with 2.5 mm luminal diameter. Test groups (n=6) either …

Development Of A Model To Predict Maximum Crack Width And Spacing In Reinforced Concrete Beams Under Flexural Stress, Saeed Alghamdi

Theses and Dissertations

Cracking in reinforced concrete structures is unavoidable due to the low tensile strength of concrete. Even though minimizing cracks on exposed concrete surfaces is significantly important from the aesthetics point of view, it is also very important for the durability and overall performance of the structure.

Flexural members must be designed to minimize cracking that may occur during the structure's service life. Even though there has been a lot of experimental work on crack width over the last several decades, a literature review reveals that researchers still can't agree on which variables are most important. Part of the reason for …

High Intraspecific Diversity Of Pocillopora Damicornis In Southeast Asia Reflects Adaptive Potential To Climate Change, Maria Lucille Carr

Theses and Dissertations

Marine heatwaves are increasing in intensity and frequency because of increased emissions of greenhouse gases. On coral reefs, warmer temperatures cause coral bleaching, mortality, and shifts in benthic composition. However, coral bleaching responses and survival vary geographically. Several hypotheses may explain such geographical differences in thermal tolerance, including the possibility that some localities may support higher intraspecific diversity than other localities, increasing the likelihood of survival of some individuals through heatwaves. Here we assessed geographic patterns of intraspecific genetic diversity in the ubiquitous coral Pocillopora damicornis. Intraspecific genetic diversity was assessed for 428 sequences across 44 sites in the Pacific …

Representation Learning For Generative Models With Applications To Healthcare, Astronautics, And Aviation, Van Minh Nguyen

Theses and Dissertations

This dissertation explores applications of representation learning and generative models to challenges in healthcare, astronautics, and aviation.

The first part investigates the use of Generative Adversarial Networks (GANs) to synthesize realistic electronic health record (EHR) data. An initial attempt at training a GAN on the MIMIC-IV dataset encountered stability and convergence issues, motivating a deeper study of 1-Lipschitz regularization techniques for Auxiliary Classifier GANs (AC-GANs). An extensive ablation study on the CIFAR-10 dataset found that Spectral Normalization is key for AC-GAN stability and performance, while Weight Clipping fails to converge without Spectral Normalization. Analysis of the training dynamics provided further …

Development Of Chiral Lewis Base Catalysts For Chlorosilane-Mediated Asymmetric C-C Bond Formations, Changgong Xu

Theses and Dissertations

The chiral hydrazine is a crucial structural motif that serves as pivotal structural elements in numerous natural products and biologically significant molecules. We are particularly interested in the catalytic asymmetric reduction of hydrazones, as well as the catalytic asymmetric propargylation and allenylation of hydrazones, because they provide direct pathways to these enantio-enriched chiral building blocks. In this work, we will explore the potential of two different categories of chiral Lewis base catalysts in the said transformations.

Developed by another student in our group, axial-chiral 3,3’-triazolyl biisoquinoline N,N’-dioxides derived catalysts are tested and demonstrated its capability in activating various hydrazone …

Denoising Diffusion Probabilistic Models Based Accelerated Mri, Alexander Francis Bugielski

Theses and Dissertations

Magnetic Resonance Imaging (MRI) is a cornerstone in obtaining intricate visualizations of anatomy and physiological processes within the human body. However, its extensive scan duration not only causes patient discomfort but also increases the likelihood of motion-induced artifacts in the images. To address such a challenge, this study investigates deep neural network models for reconstructing high-resolution MRI images from noisy and significantly undersampled data in a supervised learning manner. Specifically, it compares three models: a conventional U-Net, a self-attentive U-Net, and an innovative probabilistic diffusion model that builds upon the self-attentive U-Net architecture. These models are evaluated on their ability …

Molecular Insights Of Paraoxonase 2 In Advanced Glycation End Product Induced Endothelial Dysfunction, Ramya R

Theses and Dissertations

Diabetes mellitus (DM) is a metabolic disorder associated with various vascular complications and affects the function of the endothelial cells. Elevated blood glucose levels accelerate the formation of advanced glycation end products (AGEs) by Amadori rearrangement and bind to their Receptor for the advanced glycation end product (RAGE) and evoke release of key pro-inflammatory cytokine proteins leading to endothelial dysfunction. Paraoxonase 2 (PON2) is an endogenous intracellular enzyme, localised in mitochondria, endoplasmic reticulum (ER), and nuclear membrane with numerous properties, like anti-inflammatory, anti-apoptotic and anti-oxidant.

Our present study aims to ascertain the effect of AGEs on PON2 activity and expression, …

“You Have To First Recognize That There’S A Problem Before You Can Enact Change”: A Mixed-Methods Study Of General And Special Education Co-Teachers’ Critical Consciousness And Agency In Enacting Socially Just Inclusive Practices, Latifa Sebti

Theses and Dissertations

Inclusive education transcends the physical integration of students with disabilities in inclusive classrooms, demanding a commitment toward socially just inclusive practices. The purpose of this exploratory mixed-methods study is to investigate inclusive co-teachers' critical consciousness and agency in socially just inclusive practices, specifically for students of color with disabilities. The quantitative phase, with a survey of 241 teachers, revealed a structural equation model showing relationships between critical awareness about intersectionality, attitudes toward inclusion, self-efficacy in inclusive teaching, agency, and critical action. The open-ended responses indicated two teacher profiles based on their level of critical consciousness. The qualitative phase included interviews …

Sleep It Off? Exploring Sleep Duration And Bedtime Regularity As Potential Protective Moderators Of Early Adversity's Impact On Mental Health In Infancy, Childhood, And Adolescence, Sarah Lindsey Hipwell Kamhout

Theses and Dissertations

Introduction: Adverse Childhood Experiences (ACEs) are known to increase risk of mental health challenges throughout development, and sleep is known to decrease risk of mental health challenges. These have not been studied in tandem in younger cohorts. We investigated whether interactions between sleep duration and sleep regularity would moderate the impact of ACE exposure on risk for the development of mental health disorders. Methods: We conducted secondary cross-sectional analyses on the 2020-2021 waves of the National Survey of Children's Health (NSCH) (n = 92,669). We used logistic and ordinal regression to replicate known main effects of ACEs (total, household, community, …

The Effects Of Adverse And Positive Childhood Experiences On Childhood Mental Health And Behavior Problems, Jane Grace Smith

Theses and Dissertations

Adverse childhood experiences (ACEs) are traumatic childhood events with enduring repercussions on child well-being, while positive childhood experiences (PCEs) have been identified in emerging research as capable of offsetting the effects of ACEs. However, little research investigates the combined impact of ACEs and PCEs on child outcomes, which can inform better aid for children exposed to ACEs. The purpose of this study is to address these important gaps in existing ACE literature. Using data from the National Survey of Child Health (NSCH) 2020-2021 (N = 60,809), I examine the individual and interactive effects of ACE, PCEs, and gender on childhood …

Lessening Lacunas: A Genetic Critique And Literary Analysis Of Female Indigenous Characters In Maria Firmina Dos Reis's Gupeva, Xana Furtado

Theses and Dissertations

One year after publishing Úrsula (1860), Maria Firmina dos Reis (Brazil’s first female novelist) published Gupeva, a novella that acts as a continuation of José de Santa Rita Durão’s Caramurú: Poema épico do descubrimento da Bahia (1781). Gupeva depicts the ultimately tragic love between Épica, an indigenous woman, and Gastão, a French sailor. The novella was published twice more during Reis’s lifetime—once in 1863, with minimal orthographic changes, and again in 1865, this time with quite drastic modifications. The editors of Echo da Juventude, where the 1865 version was published, acknowledged these changes by asking readers to be "indulgentes para …

Conservation And Management Of Greater Sage-Grouse In Strawberry Valley: Quantifying Influences On A Traditional Capture Method And Long-Term Trends In Clutch Size, Janae Radke

Theses and Dissertations

The greater sage-grouse (Centrocercus urophasianus) is a species of conservation concern that has undergone serious declines in the last century. The Strawberry Valley sage grouse population in Utah underwent such a decline from an estimated 3,500 sage grouse in the 1930s to 150 sage grouse in the early 2000s. This decline initiated a long-term conservation and monitoring project in Strawberry Valley with the goal of preserving the sage grouse population. As part of this ongoing conservation project, we investigated factors that impact the success of capturing sage grouse using the night-lighting method (Chapter 1). We found that capture success is …

Trip - Transformer Interatomic Potential Predicts Realistic Energy Surface Using Physical Bias, Bryce Eric Hedelius

Theses and Dissertations

Accurate interatomic energies and forces enable high-quality molecular dynamics simulations, torsion scans, potential energy surface mapping, and geometry optimization. Machine learning algorithms have enabled rapid estimates of energies and forces with high accuracy. Further development of machine learning algorithms holds promise for producing general potentials that support dozens of atomic species. I present my own Transformer Interatomic Potential (TrIP): a chemically sound potential based on the SE(3)-Transformer. TrIP's species-agnostic architecture--using continuous atomic representation and homogenous graph convolutions--encourages parameter sharing between atomic species for more general representations of chemical environments, keeps a reasonable number of parameters, serves as a form of …

Sagefire: An Agent-Based Model Of Heat Dynamics In Sagebrush Steppe Ecosystems During A Fire Event, Samuel Joseph Knuth

Theses and Dissertations

Context: The Great Basin in the western US features arid to semi-arid climates and sagebrush steppe ecosystems. Increased fire frequency can negatively impact these ecosystems by promoting invasive species. Agent-based modeling is a valuable tool to study fire dynamics in sagebrush steppe ecosystems, offering insights in management strategies and ecosystem resilience. Objectives: We developed SageFire, an agent-based model, to simulate heat dynamics influenced by shrub cover during fires in the Great Basin. Our objectives were to accurately classify ground cover types, incorporate classified imagery into a simulation model, and accurately visualize fire intensity based on the spatial arrangement of the …

Spatial Distribution Of Soil Nutrients And Properties As A Function Of Vegetation Distribution, Fire, And Rodent Activity, Nathan O. Jones

Theses and Dissertations

Fires are becoming larger and more frequent in the deserts of North America, driven largely by the expansion of invasive annual grasses. Rodent consumers can curb invasive grass expansion through plant herbivory, but the top-down effects of this pressure on soil resources are understudied. In shrub dominated deserts, islands of fertility under shrub canopies are surrounded by nutrient poor interspace soils that dictate patterns of vegetative growth. Little is known of how top-down controls from rodents and fire may interact with fertile island topography. These studies explore the effects of fire, rodent activity, and fertile island topography on plant available …

Andromedus: A Novel, Ariel Renae Hochstrasser

Theses and Dissertations

Andromedus "Midas" Hellebore is a half-fae necromancer living in Portland, Oregon. When he was a child, he grew up in a brothel on a fae territory near the Pacific coast on an island called Duckwell. The matron of said brothel tried to sell him to be a blood pet for a man named Mr. White, both to be a sex slave and to consistently produce fae blood, which consumed by humans could give them the magic fae folk are born with. However, a few of the escorts at the brothel - including Orla, the one who chose to raise him …

E Afua Mai Mauga Manuia O Nu'u: Conservation From Mountains To Reefs In Tropical Pacific Islands, Tavailau T. Segi

Theses and Dissertations

Soil erosion is the main exacerbating threat to climate change impacts in tropical Pacific islands, particularly to steep and mountainous volcanic islands. The morphological features (steep and mountainous), short distance from ridge to reef, frequent storm events, extended raining season, and accelerating developments from growing populations pose serious threats to terrestrial and marine resources. Perhaps the most threatening part is the high dependency of their human populations on the land and ocean for food supplies, supporting national economies, and sustaining culture and human well-being. Locals, governments, and non-governmental organization projects are underway to improve protection and management of natural resources …

Acceptable Things, Janaya Lucile Tanner

Theses and Dissertations

My thesis is a collection of short stories which explore motherhood through the lens of science fiction. The stories take place in various settings and landscapes in imagined future for humanity and are set within the frame of a sentient space station speaking to her daughter. The stories explore ideas of pregnancy, access to maternal care, and relationships between mothers and daughters. Environmental concerns and the link between maternal bodies and natural landscapes are prominent throughout the collection. Ultimately, these stories ask and seek to explore the question of what motherhood can mean, how our relationships to our parents and …

Development Of A Molten Salt Reactor Design And Design Framework For Overall Reactor Performance Prediction And Optimization, Andrew William Larsen

Theses and Dissertations

This dissertation introduces a novel approach to nuclear reactor design, emphasizing molten salt reactors (MSRs) to address the global need for safer, more efficient, and sustainable energy sources. It confronts the inherent challenges of nuclear fission reactors--proliferation risks, cost efficiency, waste management, and passive accident prevention--by developing an innovative MSR model and a machine learning (ML)-based optimization framework. The molten salt microreactor (MSMR), devised by researchers at Brigham Young University, utilizes thermally conductive plates for efficient heat dissipation during operational anomalies, ensuring safety within operational limits. This design was rigorously tested using STARCCM+ for fluid dynamics modeling and RELAP5-3D for …

Transferable User-Friendly Machine Learning For Normal Boiling Point Prediction, Frank Tafadzwa Mtetwa

Theses and Dissertations

The estimation of thermophysical properties of chemical compounds holds considerable importance across a multitude of fields, ranging from material science to process design. Among these properties, the normal boiling point (NBP) stands out as a pivotal parameter in scientific and engineering contexts, as it elucidates the state of a substance under standard conditions commonly encountered in nature. Additionally, NBP is extensively documented in various reference materials and databases. Given its paramount importance and widespread availability, prediction methodologies for other properties such as critical temperature, liquid density, vapor pressure, surface tension, liquid viscosity, liquid thermal conductivity, and flash point often rely …

"The First Fruits Of A Woman's Wit": Reclaiming The Childbirth Metaphor In Aemilia Lanyer's Salve Deus Rex Judaeorum, Carolyn Mae Shakespear

Theses and Dissertations

The childbirth metaphor adopts imagery from female bodies carrying and delivering children to describe the effort and relationship of a poet to his/her poem. This was a commonly used trope in the renaissance, particularly by male authors. This thesis examines the way early modern woman poet, Aemilia Lanyer uses the childbirth metaphor in her poem, Salve Deus Rex Judaeorum. Lanyer ultimately considers not only the physical realities of childbirth in her use of the metaphor, but also the emotional, social, and theological consequences. By doing so, I argue that Lanyer reclaims the metaphor from her male contemporaries in order to …

The Role Of Caloric Intake On Achilles Tendon Health In Pre-Professional Ballet Dancers, Annie G. Smedley

Theses and Dissertations

Background: Achilles tendinopathy is a common and debilitating condition among female ballet dancers due to the large repetitive loading forces placed on their Achilles tendons during rehearsals and performances. Tendon health problems in females are exacerbated by a lack of understanding about how energy availability influences tendons. Ballet dancers, as aesthetic athletes, are vulnerable to low energy availability and can enter a spectrum disorder, relative energy deficiency in sport, that consists of low energy availability (with or without disordered eating), menstrual cycle dysfunction, and low bone mineral density (BMD). Aims: 1) To investigate the relationship between insufficient caloric intake and …

Catchment Water Storage Mediates River Flow Sensitivity To Climate Change, Brian Charles Brown

Theses and Dissertations

As patterns of precipitation and evapotranspiration change, human water security and aquatic ecosystem health depend on understanding how catchment characteristics interact with climate to control river flow. We tested factors that mediate sensitivity of river flow to fluctuations in climate using a set of 1,148 data-rich, climate diverse catchments in various parts of the world from 2001-2020. We extrapolated these results to an additional 2,012 catchments with sparser data. Using features such as vegetation, land use, hydrology, and local climate, we found that catchments with high aridity to runoff ratios (Fuh's parameter) had 380% higher runoff sensitivity to fluctuations in …

A Study Of Art Education Strategies For Remote Learning During The Pandemic, Stephanie Cook

Theses and Dissertations

In the wake of COVID-19, educators had to adjust their curriculum and pedagogies to create an environment of learning while their students couldn't come into the classroom. As teachers and students alike adapted to this new distance learning, they encountered many obstacles which made it difficult to teach and to learn compared to what they were used to in a traditional in-person classroom setting. This thesis document compiles my research about the advantages and disadvantages of remote learning before, during, and post-pandemic. The research component of this project consists of the commentary of four art educators who share what they …