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Inertial Dynamics Of Non-Spherical Particles In Fluid Flows, Takashi Yashiro

Theses, Dissertations and Culminating Projects

We investigate the dynamics of small inertial spherical and non-spherical particles in fluid flows. We consider the Maxey-Riley-Gatignol (MRG) equation, which models well the motion of spherical inertial particles in low Reynolds number flows. To study how shape affects the dynamics, we implement a corrective factor on the Stokes drag term in the MRG equation. This corrective factor, or shape factor, is based on the geometric properties of the particles. The Basset-Boussinesq history term in the MRG equation is often neglected to simplify analytical and computational studies involving the equation. We include this history term and implement a multi-step integration …

Implementation Of A Droplet Interface Lipid Bilayer System For Electrical Characterization, Olivia J. Ziemer

Honors Theses

Lipid bilayers are the fundamental structural framework of cell membranes, providing cells with both protection from the environment and interaction with the surrounding environment. Experimental investigation of lipid bilayers and embedded protein channels often involves the formation of an artificial membrane within an electrical circuit. The focus of this project is to implement and verify the functionality of a lipid bilayer characterization technique known as the droplet interface bilayer (DIB), with emphasis on cost-effective system design. To achieve this, the amplifier and software from the ELEMENTS black lipid membrane (BLM) kit were repurposed to reduce the cost of implementing a …

Community Resilience And Response To Salinity Gradients In Streams Flowing Into Biscayne Bay, Florida, Sebastian M. Jimenez

Honors Theses

Salinity is a shaping force of aquatic biodiversity, and ongoing climate change and unsustainable water-management practices are causing salinity-induced stress across coastal ecosystems. Meiofauna are small (45-1000 μm), taxonomically diverse aquatic invertebrates that are vital to ecosystems and highly responsive to environmental disturbances, making them ideal for assessing the effects of changing salinities on community structure. This study investigated how meiofaunal biodiversity (ASV richness, Faith’s phylogenetic diversity, and community composition) responded to natural salinity gradients along streams flowing into Biscayne Bay, South Florida, which is a region particularly vulnerable to salinization due to sea-level rise, altered hydrology, and watershed modification. …

Bottles, Butterflies, And Biomass: Recycled Glass Sand, Microbial Additions, And Herbivory Effects On Milkweed Growth, Kealey Skinner

Honors Theses

Plant-soil-microbe interactions are integral components of ecological networks and drive ecosystem function from the bottom-up. Whereas herbivores regulate ecosystem function from the top-down, having opposing and potentially complementary effects on ecosystem function. My thesis sought to understand how below-ground microbial communities contribute to herbivore preference and plant biomass across varied soil substrates. My thesis asked: how do substrate and soil microbial communities influence herbivore preference and plant biomass accumulation on swamp milkweed (Asclepias incarnata)? To address this question, seedlings of A. incarnata were sown in 2.5 cm wide × 10 cm deep pots filled with either natural beach sand or …

Grazed Pasture Effects On Greenhouse Gas Emissions In The Ozark Highlands, Tyler Buchanan

Graduate Theses and Dissertations

In the United States (US), grazinglands serve as the main foundation for the livestock industry, and, in Arkansas specifically, pastures are essential for rotational grazing and dairy operations. Climate change is increasingly becoming a concern in the agriculture industry, largely caused by anthropogenic activities increasing greenhouse gas (GHG) concentrations in the atmosphere, at least partly due to the nutrient recycling that occurs from animal manure additions in grazinglands. Therefore, quantifying GHG emissions from pastures is essential to better understanding the impacts of grazing on the environment. The objective of this study was to quantify and evaluate the potential effects of …

Enhancing Food Security In Stann Creek. Belize Using Meat Rabbits, Lindsey Garretson

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

In recent years, food insecurity and the prevalence of hunger have rapidly grown throughout the world, but especially within Latin America and the Caribbean. Along with growing rates of food insecurity and hunger there are increases in medical conditions including negative impacts the functioning of every major organ system, increased rates of mental illness, both overweight and underweight children, wasting in both children and adults, and anemia. Availability and access to healthy, nutritional food options can help lower the risk of these conditions. With these considerations, the goal of this project was to create an all-encompassing manual and construction guide …

Herbivory Of Phragmites Australis Along A Salinity Gradient In Connecticut Wetlands, Sydney H. Kolz

Honors Scholar Theses

Invasive Phragmites australis (common reed) is widely distributed in New England wetlands, where it often outcompetes native plants and decreases biodiversity throughout the food web. Controlling its invasion is a priority, especially in salt marsh habitat, but current management techniques are inefficient. Leveraging natural processes may improve control strategies, but in order to do so, we must first better understand how abiotic and biotic stressors interact and affect Phragmites. This study focuses on herbivory and salinity, two factors limiting Phragmites’ fitness. I measured soil salinity and quantified the damage of three herbivore guilds (i.e. gall-formers and stem-borers, leaf-chewers, and …

Investigating The Taxonomic Uncertainties Of Potentilla Rupincola, Natalie Elizabeth Hieber

Master's Theses

Landscape stewardship is an integral role for land managers that becomes more important when rare or endangered species occur within managed areas. Conservation across the landscape is a primary concern for land managers, but resources allocated for conservation can be limited due to many competing goals. Taxonomic uncertainty surrounding rare and endangered taxa, particularly plant taxa, that have historically been classified solely using morphological features further complicates conservation planning. One such taxon is Potentilla rupincola, a rare plant endemic to the eastern Rocky Mountains in Colorado. For over a century, botanists have debated whether P. rupincola is a distinct species …

The Effects Of Impervious Land Cover And Red Tide (Karenia Brevis) On The Florida Manatee (Trichechus Manatus Latirostris) In The Gulf Coast Of Florida, Anna Compton

Honors College Theses

Red tide, caused by the dinoflagellate Karenia brevis, is an algal bloom event that occurs annually in the West Florida Continental Shelf. The algae releases brevetoxin, a toxin that can be fatal to wildlife in high concentrations. These algal bloom events are thought to be exacerbated by warming ocean temperatures and increased nutrient runoff from urbanization. Red tide is responsible for the mass mortality of various marine organisms like the Florida manatee (Trichechus manatus latirostris). This study analyzes the changes in nutrient runoff and sea surface temperatures, and how these factors affected red tide cell concentrations and Florida manatee mortalities …

2026 Workshop On Bridging The Gaps: Tackling Microplastics And Nanoplastics Challenges In Coastal Ecosystems, Shenghua Wu, Kaushik Venkiteshwaran, Melike Dizbay-Onat, Alexandra Stenson, Jinhui Wang, Tina Miller-Way, Ebenezer Nyadjro, Bhuvnesh Bharti, John Weinstein, Yi Bao, Shihui Shen, Valerie Longa, Shenghua Zha, John Cleary, Marty Lind

Workshops

This report presents the findings from the 2026 Workshop on Tackling Microplastics and Nanoplastics (MNPs) in Coastal Ecosystems, which took place in Mobile, Alabama. More than 140 experts from universities, government, industry, and community organizations gathered to address the increasing issue of MNPs in coastal regions.

Can Methanogens Grow On Asteroids?, Isabella N. Reimer

Biological Sciences Undergraduate Honors Theses

Because of asteroids’ chemical features, they may serve as potential environments for life and are of interest in astrobiology. Dr. Kral’s laboratory studies methanogens, microorganisms in the domain Archaea, as possible life forms on extraterrestrial bodies. Since some methanogens can withstand harsh environmental conditions and produce methane as a waste product, methane production can be used as an indicator of potential microbial activity.  In this study, three methanogen species, Methanothermobacter wolfeii, Methanobacterium formicicum, and Methanosarcina barkeri were tested for growth on asteroid simulants based on the Orgueil (CIE-1) and Murchison (CME-1) meteorites. First, methanogen growth was assessed in the …

Foraging Plasticity And Mercury Contamination In Red-Legged Kittiwakes: A Multiple Stressor Perspective, Sam E. Clay

All-Inclusive List of Electronic Theses and Dissertations

Arctic seabirds are facing increasing stress from climate change, yet the interactive effects of multiple stressors on behavior remain poorly understood. Adopting a multiple stressor perspective promises to advance understanding of avian behavioral responses to climate change, as climate change is exposing Arctic and subarctic animals to a complex set of stressors rather than a single stressor in isolation. Using the red-legged kittiwake (Rissa brevirostris) as a model, I examined how multiple stressors, including mercury (Hg) exposure, shifting wind conditions, and varying foraging conditions linked to sea surface temperature (SST) may interact to constrain behavioral plasticity and energetically expensive behavior …

Dendroclimatic Response Of The Wet Miombo Woodland Species: A Case Study Of Mufulira District, Copperbelt Province, Zambia, Collins Chibuye Malubeni

All-Inclusive List of Electronic Theses and Dissertations

Zambia is a tropical, landlocked country that lies in the South-Central part of Africa. The climate in Zambia includes distinct dry and rainy seasons, mainly influenced by the north-south movement of the Intertropical Convergence Zone (ITCZ), which shifts seasonally. This research is focused on understanding the relationship between tree growth and climate using dendrochronology. Forty-nine tropical species, including Julbernardia paniculata, Brachystegia longifolia, and Pericopsis angolensis, were analysed for dendroclimatic potential, and 70% showed clear ring formation, indicating that trees in this locality produce distinct annual ring boundaries. For the single species chronology, thirteen cores from eight trees that were initially …

Analysis Of Volumetric Reconstruction Methods In Archaeology, Cade O'Fallon

All-Inclusive List of Electronic Theses and Dissertations

The use of Structure from Motion (SfM) photogrammetry in archaeological projects is entering a period of transition; a method of producing 3D data that is traditionally embraced as tool for documentation is being explored for its analytic potential. One such way SfM photogrammetry can be used analytically is through the calculation of volumes using photogrammetric data. The tools exist for archaeologists to be able to create and quantify volumetric models; however, the discourse on these methods is still so new there is no consensus on the best method for conducting volumetric work. Different methods of creating and isolating volumetric space …

Microplastic Composition And Exposure Pathways In Freshwater Systems: A Multi-Matrix Comparison Between Streams And Retention Ponds In Hamilton County, In, Mya Whaley

All-Inclusive List of Electronic Theses and Dissertations

Since the early 1900s, the use of plastics has increased exponentially. The breakdown of plastic materials has exposed all ecosystems to microplastics (small particles of plastic < 5 mm), which are now ubiquitous in natural settings. Microplastics have a relatively large surface area, and many chemicals adsorb to these small particles, impacting their fate and transport of pollution. While microplastics have been found in virtually every setting on Earth, research is necessary to understand their impact on freshwater ecosystems and biogeochemical cycles. The focus of this research was to investigate microplastic compositions in crayfish, sediments, and water samples collected in streams and retention ponds. We analyzed trends in microplastic counts across different land-cover classes, waterbody types, and species, and compared concentrations among matrices to improve our understanding of microplastic exposure pathways in freshwater ecosystems. As a secondary objective, lead and arsenic concentrations were analyzed from sediment samples to investigate metal burdens and compare them to microplastic concentrations. Our findings revealed that, in general, urban streams had the highest microplastic concentrations within land cover categories, and retention ponds had higher microplastic counts than streams. Crayfish, such as F. rusticus had higher microplastic concentrations than F. virilis and F. propinquus, although these results may be influenced by study design. The most common microplastic type was fibers, and most common color was transparent. There was no significant correlation between microplastic and metal concentrations in sediments. We found crayfish to be adequate bioindicators of microplastic pollution, because they were less impacted by environmental variability than sediment and water samples. This research presents the first evidence of microplastics in our study species, F. propinquus, F. rusticus, and F. virlis. This work presents new evidence of microplastic accumulation in crayfish, sediments, and water from freshwater systems in the Midwestern United States. Microplastics were found in every sample type—crayfish, water, and sediment—across urban, rural, and forested landscapes, highlighting their pervasive distribution. The findings provide foundational data for assessing emerging ecological and human-health risks and emphasize the importance of sustained monitoring and research on MP contamination in freshwater environments.

The Environment, Health, And Vector Nexus: Evaluating The Spatiotemporal Variability And Societal Impact Of Ticks In Arkansas, Dalton Williams

Graduate Theses and Dissertations

Tick-borne diseases (TBDs) are a surging public health and veterinary concern in the United States. In states like Arkansas, climate change and shifting land use have recalibrated the ecological niches of vector species. This research utilizes species distribution and ecological niche modeling to assess the spatiotemporal suitability of ixodid tick habitats, specifically where environmental and socioeconomic factors intersect. By integrating spatial science with public health frameworks, this study identifies priority intervention areas in underserved rural regions where healthcare resources are often constrained. This study provides a comprehensive methodological framework, leveraging remote sensing datasets and historic disease data to delineate exposure …

Urea-Based Boronium Salts As Antimicrobial Agents, Gabriel Allen Merchant

Honors Theses

Quaternary ammonium compounds (QACs) are widely used in disinfectants due to their ability to inhibit the growth of and eliminate microbes. The potency, broad-spectrum activity, and low cost of QACs have made them a cornerstone of modem hygiene. In recent years, QACs have garnered many health and safety concerns due to their overuse and subsequent accumulation in the environment. The increased use of QACs has further led to an increase in antimicrobial-resistant bacteria, making the synthesis of novel antibacterial compounds vital to combat this growing threat. Recent advances in boronium salts offer a unique alternative to address these adverse effects. …

Assessment Of Mississippi Landfill Capacity In Relation To Waste Generation And Land-Use Constraints, Jason C. Anderson

Master's Theses

Municipal solid waste (MSW) management presents a growing challenge in Mississippi as population trends, socioeconomic change and regional development continue to place pressure on existing landfill capacity. This thesis examines waste generation and disposal patterns from 2000 through 2022 across Mississippi counties, with projections extending to 2050. Historical landfill tonnage data was gathered and compiled from the Mississippi Department of Environmental Quality (MDEQ) and analyzed using regression models in Excel and RStudio, with forecasts generated for both in-state and out-of-state waste flow. Results highlight significant variations among landfills, including differing closure timelines, changing county service areas and notable shifts in …

Quantifying Discard Mortality Of Undersized And Ovigerous Crabs In The Gulf Of Mexico Blue Crab Fishery, Micayla Cochran

Master's Theses

Blue crabs support a valuable commercial fishery in the Gulf of Mexico. Most states require the release of undersized and ovigerous blue crabs, yet mortality of these discarded crabs is an understudied component of total mortality. The first objective of this project was to quantify discard mortality of non-target crabs using bycatch surveys across the Lake Pontchartrain–Mississippi Sound coastal system. Ovigerous crabs were most common at high salinities and temperatures, whereas undersized crab presence was inversely correlated with soak time, temperature, and the number of crabs per trap, and also varied among geographic locations. A reflex action mortality prediction assessment …

Redeveloping Mississippi: A Case Study On Brownfields In Central & Southern Mississippi, Sahrah R. Yeroozedek

Master's Theses

Brownfields, or properties that are or possibly are contaminated with dangerous materials, represent a common obstacle for communities in Mississippi. The real or potential presence of contaminants at these sites often deters investors due to costly cleanup requirements (EPA, n.d. -b). The Environmental Protection Agency (EPA), through its Brownfield Revitalization Program, implemented guidelines for covering the costs and labor associated with the remediation of these properties. The EPA is not, however, responsible for redevelopment that supports long-term environmental and economic sustainability. Although the EPA maintains inventories of all Brownfields, there is also no comprehensive database of Brownfields and their current …

College Of Natural Sciences Spring Newsletter, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

[Page 1] Dean's Message
[Page] 2 Awards & Recognitions // Student Spotlights
[Page] 3 Zhang Named to Landsat Science Team // The Power of Teaching
[Page] 4 “Science as Art” Competition Welcomes High School Artists
[Page] 5 Testing for “Forever Chemicals” in Surface Water // New Faculty Spotlight
[Page] 6 Ambassador Initiated Outreach
[Page] 7 57th Annual Geography Convention
[Page] 8 Twice the Impact on On Call with the Prairie Doc
[Page] 9 Making Staple Foods Healthier // Halaweish & Cole-Dai Retire
[Page] 10 Drone Day 2026
[Page] 11 Student Research, Scholarship, and Creative Activity Day (SRSCAD)
[Page] 12 Ceremony …

Comparative Development Of Mof‑Based And Mof‑Free Agnp Functionalized Zno Nanorod–Cotton Fabric Composites For Photocatalytic Applications, Md Al Mamun

Master's Theses

Photocatalysis offers a cost‑effective and environmentally friendly strategy for degrading organic pollutants and addressing energy and environmental challenges. This study initially explored MOF‑based cotton‑fabric‑supported ZnO nanorod composites but found that the MOF component primarily acted as an adsorbent rather than an effective photocatalyst. Consequently, MOF‑free composites were developed by directly growing ZnO nanorods on cotton fabric and functionalizing them with silver nanoparticles. Photocatalytic testing revealed that AgNP‑modified ZnO nanorods, particularly at 10 mM AgNP, exhibited superior dye degradation efficiency, thereby demonstrating a scalable and effective photocatalytic platform.

Synthesis Of Novel 1,2,3-Triarylnaphthalenes Via Intermolecular Dehydro-Diels-Alder Reaction, Ethan C. Dailey

Honors Theses

The photo-dehydro-Diels–Alder (PDDA) reaction is a useful method for the construction of substituted naphthalene derivatives from acyclic precursors. While intramolecular variants of this transformation are well established, intermolecular PDDA reactions remain rare due to challenges associated with controlling reactivity under photochemical conditions. Previous studies suggest that electron-withdrawing substituents can promote intermolecular cycloaddition by increasing alkyne polarization and stabilizing reactive intermediates. In this work, the effect of enhanced electron-withdrawing character on intermolecular PDDA reactivity was investigated through the incorporation of a 2,3,5,6-tetrafluoropyridinyl substituent. Corresponding alkyne substrates were synthesized and subjected to photochemical conditions, resulting in the formation of 1,2,3-triarylnaphthalene products. The …

Evaluating The Effects Of Urbanization On Meiofauna Biodiversity In Chattanooga’S Lentic Ecosystems Through Gis Applications, Keyle M. Bryant

Honors Theses

Urbanization is a leading driver of biodiversity loss in freshwater ecosystems, yet its effects on meiofauna—microscopic invertebrates that serve as key bioindicators of ecosystem health—remain poorly understood in lentic environments. This study evaluated the effects of urbanization on meiofaunal biodiversity in ten lentic waterbodies across Hamilton County, Chattanooga, Tennessee, by integrating environmental DNA (eDNA) metabarcoding, in-situ abiotic measurements, and Geographic Information Systems (GIS)-based land use analysis. Water samples were collected between January and April 2023 and processed using 18S rRNA amplicon sequencing to assess biodiversity as richness (amplicon sequence variants or ASVs, phylogenetic diversity or PD, and community composition). Land …

Environmental Awareness And Community Sentiments In A Superfund Site: A Study Of South Chattanooga, Mia Dial

Honors Theses

The concept of environmental injustice refers to the disproportionate exposure of marginalized communities to environmental hazards, often resulting from the placement of industrial sites, waste facilities, or other environmentally harmful infrastructure in areas with limited political and economic power. Alton Park, a historically underserved neighborhood in Chattanooga, Tennessee, faces elevated environmental risks due to its proximity to the South Chattanooga Lead Superfund Site and legacy industrial contamination. This study used semi-structured individual interviews to assess community awareness, perceptions, and behaviors related to environmental hazards in Alton Park. Residents generally reported some awareness of the Superfund site, though knowledge was often …

Resilience By Living With The Land And Community: A Case Study Of A Local Food Forest, Olivia Beck

Honors Theses

Imagine a public space where food, leisure, outdoor activity, and community engagement occur in one place, all in an urban forest ecosystem. For many, this is a hopeful vision of the future, and that is exactly what the idea of an urban food forest provides. In agroecology, a food forest or forest garden consists of planting diverse edible plants and mimicking the patterns of natural ecosystems. The intricate planning and design ensure the forest is self-sustaining, much like a natural forest, making it very resilient once established. However, they face many challenges and take time to grow and develop to …

Growing Change: A Gis Spatial Analysis To Plan Urban Gardens In Chattanooga, Carson A. Chalk

Honors Theses

Food insecurity and limited access to fresh nutritious food in Chattanooga is a prevalent issue, primarily among lower socioeconomic households, and can put strain on overall well-being. This study aimed to identify suitable vacant parcels in Chattanooga where urban gardens could be developed using a GIS-based spatial analysis. Spatial data involving vacant parcels, slope, zoning, and proximity to grocery stores was cross referenced with socioeconomic data focused on poverty rates, vehicle ownership, and mean household income to identify the most suitable sites in areas of greatest need. Sites identified as suitable through GIS were then visited to verify their suitability. …

Aircraft Fault Detection Via Weight And Bias Analysis Of A Custom First Neural Network Layer, George Harrison Chen

Theses and Dissertations

Fault detection in aircraft is traditionally handled through redundant hardware and comparison algorithms to detect failures. Alternatives like model-based residual generation and data-driven approaches such as supervised fault classification and unsupervised anomaly detection have been explored, but they suffer from practical limitations; model-based methods require accurate system models, and data-driven methods have large constraints on the data limiting scalability and adaptability. This work presents a purely data-driven neural network architecture featuring a custom first layer designed for real-time fault detection where the weights and biases of this layer are used to detect faults. The network requires zero supervision and complements …

Insights Into Androgen Receptor Allosteric Modulation By P,P'-Dichlorodiphenyldichloroethylene Binding At The Binding Function-3 Site And Site-Specific Binding Function-3 Mutations, Emanuel Aggeo Flores

Theses and Dissertations

One of DDT’s metabolites, p,p’-dichlorodiphenyldichloroethylene (DDE), has been classified as an endocrine disrupting chemical (EDC) due to its ability to interfere with hormone signaling by binding to nuclear receptors (NR) such as the androgen receptor (AR).

Structurally, the AR contains a ligand-binding domain (LBD) where endogenous steroids bind. Furthermore, the LBD contains a surface binding site known as binding function-3 (BF-3), which studies suggest exerts an allosteric effect on bound DHT when small, hydrophobic molecules bind.

Here, we present a study that examines how specific BF-3 site mutations and DDE binding affect steroid stability within the LBP utilizing computational methods. …

Geospatial Science And The Changing Environment: Applied Methods For Sustainable Agriculture And Landscape Management, Harrison Wakefield Smith

Graduate Theses and Dissertations

Rapid environmental change is disrupting agricultural productivity, ecological function, and the long-term resilience of managed landscapes. At the same time, the rapid growth of geospatial data science has improved our understanding of environmental change and increasingly is being used to improve sustainability in agricultural and environmental management. However, critical gaps remain that limit the applicability of data-driven insights in landscape management. This dissertation investigates the potential of geospatial analytics for sustainable agriculture and landscape management, with a focus on applied methods that operate across spatial and temporal scales. Using field, landscape, regional, and national datasets, it explores the capabilities and …