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Flow Field Surrounding Bluegill (Lepomis Macrochirus) During Suction-Feeding, Jensine Caroline Coggin

Electronic Theses and Dissertations

Suction-feeding is a common method for capturing prey by aquatic organisms and contributed to the diversification of fishes by enabling them to consume a wide range of prey. Suction-feeding is a complex fish-fluid interaction governed by various hydrodynamic forces: inertia, unsteady, viscous, and pressure gradients. These forces are described by the coupling between the flow physics equations (Navier-Stokes) and the dynamic behavior of the fish (motion and forces). However, the distribution of the pressure field that drives this process, and the extent to which suction-feeding is three-dimensional, remain underexplored. I estimated the pressure within the flow field surrounding the mouth …

Ediacaran Paleocommunity Structure, Body Size Evolution, And The Rise Of Complex Animals, Matthew Philip Craffey

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Ediacaran period (635-538ma) is a key interval in the evolution of life as it records the first macroscopic animal communities. Major extinction pulses appear to have altered the composition of the global marine biosphere between each sub-interval of the Ediacaran Period: the Avalon, White Sea, and Nama assemblage Zones. While considerable attention has been paid to the causes of these extinction pulses, less has been afforded to the consequences of Ediacaran biotic turnover for community organization and function. Moreover, it is unclear how body size - the defining trait of macrofauna - affected the transition between animal groups across …

Spatial Ecology And Predator–Prey Interactions Of Mountain Lions In California's San Francisco North Bay, Jacob A. Harvey

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding spatial ecology and predator-prey interactions are central to wildlife ecology and conservation. We tracked mountain lions with GPS telemetry to evaluate space use, predator-prey interactions, and resource selection in California’s San Francisco North Bay, USA. In Chapter 1, we evaluated the influence of human disturbance on home range size, prey composition, and kill rates on black-tailed deer (Odocoileus hemionus columbianus) across an urban-rural gradient. Both males and females increased home range size with increasing development at low to moderate levels of development, but female home range size stabilized across greater proportions of development while male home range …

Maggot Mass Effect On The Development And Survival Of Forensic Blow Flies, Akomavo Fabrice Gbenonsi

School of Natural Resources: Dissertations, Theses, and Student Research

Forensic entomology scientists use blow flies' developing patterns to estimate the postmortem interval (PMI). However, larval aggregations produce metabolic heat, resulting in complex microclimates that may change growth timetables. This study investigates how larval density and associated temperature changes affect the development and survival of two forensically essential blow fly species, Lucilia sericata and Calliphora vicina.

This study examined how larval density and associated thermal profiles affect the development of both blow fly species. Using a split-plot design, we tested four larval densities at 25°C and 30°C, with temperature gradients measured via thermocouple at four mass positions three times …

Assessment Of Sampling Gears For Bigheaded Carp In Mid-Order Prairie Rivers In Nebraska, Brett M. Anderson

School of Natural Resources: Dissertations, Theses, and Student Research

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis (collectively bigheaded carp) have invaded tributaries to the Missouri River and Platte River in Nebraska, USA. Information pertaining to efficient sampling protocols for assessing bigheaded carp populations as well as benefiting removal efforts is needed. Herding is a method used to increase the capture efficiency and detection probability of adult bigheaded carp by simultaneously using active and passive sampling gears. During June-July 2023, four herding techniques were assessed regarding their ability to elicit directional movement past an enclosure gate. The combination of sound and electrofishing resulted in the highest mean …

Radar Precursors To Severe Weather Reports In Left-Moving Supercells, Eric A. Carothers

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

While much research has examined dual-polarimetric signatures of right-moving supercells, very little has been done with left-moving supercells. Given that left-moving supercells are thought to be disproportionate producers of large hail, understanding their internal dynamics is vitally important. This study examines differences and trends in the dual-polarimetric signatures of left-moving supercells to identify precursors to severe weather reports. A dataset of left-moving supercells associated with severe weather reports was created. These storms are processed with an automated analysis algorithm that identifies and quantifies the polarimetric signatures in each storm. A method for analysis of differences and trends in their dual-polarization …

Rectifying The Tephrostratigraphic Record Of The Pacific Northwest, Casey J. Crawford

Boise State University Theses and Dissertations

The Mid-Miocene Climatic Optimum (~17-14Ma) marks the last time that Earth’s atmospheric CO₂ concentrations were as high as modern levels, correlating to a peak of significant warming during an otherwise cooling trend through the Cenozoic. To understand how modern ecological systems may respond to CO₂ -induced climate change, paleontologists are studying how plant type and diversity changed with the rise and fall of CO₂ concentrations over the ~3Ma interval, and utilize intercalated tephras amenable to radioisotope geochronology to bracket fossiliferous horizons in time. The legacy model for tephrostratigraphy in the Pacific Northwest utilized Fe and Ca concentrations …

Bpa Adsorption On Microplastics In Different Chemical Conditions, Addison Zehren

University Honors Program Senior Projects

Microplastics (plastic particles < 5 mm in size) are increasingly seen as a health and environmental issue, both for their direct effects when ingested by living organisms and for their ability to adsorb and concentrate other pollutants. Current water treatment processes do not adequately remove microplastics from municipal water supplies, so a thorough understanding of how microplastics affect water quality is needed. The objective of this study is to evaluate the effects of certain water quality parameters on the ability of polystyrene microplastics (PS MPs) to adsorb Bisphenol A (BPA). BPA is an endocrine disruptor (chemically like estrogen) used in plastics which can be released into the environment and act as a water pollutant. Water quality chemical parameters investigated were chloride, nitrate, phosphate, and copper ions. Concentrations of each solute were selected based upon Environmental Protection Agency (EPA) guidelines and previous results obtained from testing Chicago River water samples. A constant amount of PS MPs and BPA were added to each sample and the mixtures were shaken for 5 days to allow time for the BPA to adsorb. The samples were then filtered and the amount of BPA left in the water was determined by measuring its UV absorbance on a UV-vis spectrophotometer. BPA concentrations decreased in the water indicating that it had been adsorbed onto the microplastic surface, with the highest adsorption present with copper, which reduced BPA concentrations from 6.7 mg/L to 3.9 mg/L. Statistical analyses showed differences between copper, phosphate, nitrate, and chloride (df = 9, p = 0.002). Future work can apply these results to investigate the implications of pollutant transportation in urban waterways like the Chicago River.

Assessment Of Lake Salvador Shoreline Dynamics To Support Restoration Of Submerged Aquatic Vegetation In Jean Lafitte National Historical Park And Preserve, Louisiana, Lydia V. Dipaola

LSU New Orleans Theses and Dissertations

High wave energy degrades shoreline habitat between Lake Salvador and Jean Lafitte National Historical Park and Preserve (JELA), Louisiana. JELA constructed a northern breakwater in 2004, and a southern breakwater in 2024 to protect the shoreline and promote restoration of submerged aquatic vegetation (SAV). This study analyzes Sentinel-2 imagery to quantify coastal loss along the JELA-Lake Salvador using the Change Polygon Approach, assessing annual, cumulative and major storm event-associated shoreline changes for January 2017-2025. SAV cover, nekton diversity, wave energy, and turbidity were measured before-and-after southern breakwater construction to monitor ecological and environmental outcomes. The JELA-Lake Salvador shoreline has lost …

Potamogeton Crispus Invasion: Impacts On Native Aquatic Plants And Associated Faunal Habitat, Meghan-Grace Slocombe

All Graduate Theses and Dissertations, Fall 2023 to Present

Aquatic invasive plants are non-native plants that invade a water body and displace native aquatic plants. Invasion depletes the native plant community's ability to provide ecosystem services, including improved water quality, decreased problematic algae, and increased animal habitat. The loss of these ecosystem services reduces the value of fishing, boating, and swimming opportunities in aquatic ecosystems. The potential changes in plant communities and services are particularly important at sites targeted for restoration because project goals typically include increasing ecosystem services, including wildlife habitat. Curly-leaf pondweed (Potamogeton crispus L.) is a problematic invasive species in North America. To better manage …

Managing For Disturbance: Trade-Offs Associated With Population Resilience And Ecosystem Size, Ellie Wallace

All Graduate Theses and Dissertations, Fall 2023 to Present

Populations can recover from and withstand disturbance through characteristics such as reproduction and maintaining large abundances. While these traits are beneficial to native species conservation, they can simultaneously challenge effective invasive species management. Effective invasive species control requires sufficient efforts to overcome a population's ability to recover from disturbance, such as harvest. My dissertation aimed to address how the size of an invasive population and its ability to recover from disturbance impact a suite of invasive species control methods, including those that (1) target mainly larger and older individuals (i.e., mechanical removal), (2) target all sizes of individuals (i.e., targeted …

Functional Data Analysis Of Weekly Confirmed Covid-19 Cases Per Million In Relation To Unemployment Rates And Emergency Declaration Responses, Elaina Kay Mcgovern

Boise State University Theses and Dissertations

At the onset of the COVID-19 pandemic, U.S. states implemented policies that attempted to mitigate the spread and effects of the disease, such as a state of emergency declaration. This study explores the application of functional data analysis (FDA) as a means to investigate the impact of U.S. state-level emergency declarations on weekly confirmed COVID-19 cases per million during the first year of the pandemic. We focus on the duration and extent to which proactive states showed significantly different patterns of COVID-19 spread than those that implemented policies reactively. Additionally, we examine patterns in monthly state-level unemployment rates over the …

Determining The Structure And Function Of Type Iv-A Anti-Crisprs, Olivine Redman

All Graduate Theses and Dissertations, Fall 2023 to Present

Bacteria face a constant existential threat in the form of infection by viruses along with other forms of mobile genetic elements, such as bacteriophage and transposable elements. To survive, bacteria and other prokaryotes have evolved various immune systems to evade these would-be invaders. One such immune system is the CRISPR-Cas system, an adaptive immune system able to record the genetic signature of invading viruses in order to recognize and destroy them should they be encountered again in the future. In this thesis I present data that sheds light on the mechanism of one particular subtype of CRISPR-Cas systems: the type …

A Survey Of Master's Qualifying Exam Practices And Content In Real Analysis, Zachary M. Coverstone

All Graduate Theses and Dissertations, Fall 2023 to Present

Graduate programs in mathematics are intended to develop experts in mathematics. As part of a graduate program, many students are expected to engage in a qualifying examination that can serve myriad purposes. This dissertation investigates real analysis qualifying examinations at the master's level through a nation-wide survey of institutions in the Association of Public and Land-Grant Universities (APLU). This study reveals the practices in administration of real analysis qualifying exams, institutions reported offering traditional, pencil-and-paper exams and generally asked students to prepare individually using previously administered exams. The survey results show that approximately two in three APLU institutions offering master's …

Enhancing Product Image Classification: Utilizing Machine Learning Models For Retail Applications, Avery A. Thompson

Data Science Undergraduate Honors Theses

The expansion of e-commerce has continued at a blinding pace since the COVID-19 pandemic, and retailers are constantly looking for new ways to retain customers. Ensuring that diverse and well-classified images are on product pages has been a paramount method for retailers to ensure retention as they increase product engagement and sales and enhance user experience. Managing and labeling these vast catalogs of images by hand is becoming increasingly infeasible, so some online retailers have started to turn to automated classification models to assist them. Accuracy in these classification models is integral, as a good image classification model can improve …

A Comparative Analysis Of Nf-Κb1 Gene Regulatory Sequence Methylation In Normotensive And Hypertensive Kenyans, Aaryan Barlas Piracha

Honors Theses

Accounting for the majority of deaths worldwide, non-communicable diseases (NCDs) present the greatest health challenge of the twenty-first century. Specifically, cardiovascular diseases (CVDs) exceed all other NCDs in annual deaths and especially affect low- and middle-income countries (LMICs). Hypertension, being the primary risk factor for CVD, affects over 75% of adults in LMICs due to inadequate health care and preventative measures. Additionally, epigenetic modifications of DNA are important mechanisms that regulate gene expression; DNA methylation, in particular, affects cytosine residues in cytosine-phosphate-guanine (CpG) islands on regulatory sequences. Previous research in our laboratory analyzed percent methylation at 8 different CpG islands …

Toxicity And Biodegradability Of Novel Boronium Vs Conventional Ammonium-Based Antimicrobial Compounds In Wastewater Treatment Systems, Noor Shalan

Honors Theses

Quaternary ammonium compounds (QACs) are highly effective as disinfectants, herbicides, and pesticides; thus, overuse causes elevated levels of residual toxicity in domestic and industrial wastewater. QACs can be toxic to essential bacteria breaking down pollutants in wastewater treatment plants (WWTPs) and can remain untreated in effluent, harming the environment, and contributing to antibiotic resistance, posing risks to human health. Novel boronium-based antimicrobial compounds have demonstrated efficacy in eliminating bacteria, fungi, and viruses. If the boronium compounds exhibit lower residual toxicity, they could offer a promising alternative to QACs. Because these compounds are still in development, their potential toxicity to the …

Ghosts In Glass: Ghost Crabs As Judges Of Glass Sand For Coastal Restoration, Emily Parrish

Honors Theses

Over 60% of the Gulf of Mexico coastline is actively eroding, which has resulted in thousands of miles of lost coastline over the last 100 years. This drastic loss of coastal land highlights the dire need for coastal restoration across the entirety of the Gulf Coast. A vital aspect of restoring these eroded areas is replenishing eroded substrate, traditionally conducted through offshore dredging of substrates which comes with high economic and ecological costs. Recycled glass sand may be able to fill this role and reduce our reliance on dredging while lowering the amount of glass waste entering landfills each year. …

Chemistry Education At The University Of Southern Mississippi Through Computation And Active Learning Methods, Sadie Pitre

Honors Theses

Education is one of the pillars of society. It evolves alongside scientific progress, shaping how students learn and engage with complex topics. The incorporation of new educational standards at The University of Southern Mississippi (USM) was implemented in two parts: through computational chemistry laboratory exercises for teaching laboratories and through the synthesis of organic molecules for research projects in an upper-level spectroscopy class. The goal of these projects is to improve learning of abstract and/or complex topics beyond the teaching methods traditionally utilized in the undergraduate laboratory and in the classroom.

Computational chemistry, which uses theoretical calculations to model molecular …

Elucidating The Mechanisms Of Collagenase H From Hathewaya (Clostridium) Histolytica In Collagen Degradation And Developing A Cross-Linked Platform For Efficient Capture And Release Of Adeno-Associated Virus Serotype 2 (Aav2), Adjoa Otubea Bonsu

Graduate Theses and Dissertations

In biological systems, Hathewaya (Clostridium) histolytica secretes collagenases that degrade structural collagen in host tissues and cause tissue necrosis. Despite their detrimental effects, these enzymes have significant therapeutic potential by effectively digesting various collagen subtypes to treat connective tissue disorders. The bacterium produces two homologous collagenases, ColG and ColH, with a catalytic module crucial for hydrolyzing collagen and binding domains, including collagen-binding domains (CBDs) and polycystic kidney disease-like domains (PKDs), for substrate interaction.

Although the crystal structure of the catalytic module of collagenase G (ColG) has been determined, shedding light on its chew-and-digest mechanism, the structure of collagenase H (ColH) …

Conservation Agriculture Practice Effects On Greenhouse Gas Emissions From Fine-Textured Soils In Arkansas, Lauren Gwaltney

Graduate Theses and Dissertations

Biochar application and reduced tillage (RT) are both practices within the conservation agriculture framework, but specific impacts of these practices on direct greenhouse gas (GHG) emissions still require investigation in varied agricultural systems. This research aimed to evaluate the effects of biochar source (i.e., powder- and pellet-sized) and application rate (i.e., 0, 2.5, and 5 Mg ha^-1) on GHG production in simulated furrow-irrigated rice (Oryza sativa) in a greenhouse experiment, and to evaluate the effects of RT relative to conventional tillage (CT) on GHG production in soybean (Glycine max) in southeast Arkansas. Both studies …

Controls On Nutrient And Sediment Export In A Non-Perennial Agricultural Stream, Kathleen Cutting

Graduate Theses and Dissertations

Climate change is expected to increase flow variability and intermittency in streams, changing the magnitude and timing nutrient and sediment delivery. This may exacerbate water quality issues in agricultural landscapes, where nutrient and sediment inputs are often elevated. Elevated nutrients can drive eutrophication in downstream waterways, and excess sediment loss can decrease primary productivity. Non-perennial headwater streams are particularly vulnerable to the impacts of climate change and agriculture as they serve as key sites for nutrient cycling at the terrestrial-aquatic interface. Despite their importance, the interactive effects of agriculture and stream intermittency, as well as unpaved roads in rural watersheds …

Nonparametric Methods For Bayesian Community Detection In Complex Networks, Kedran Young

Graduate Theses and Dissertations

Network analysis is becoming an increasingly popular interdisciplinary area of study, with emerging interest in fields like sociology, biology, economics, and ecology. Within the niche of network analysis, capturing the community structure of a network is one important achievement that many statisticians have been working toward over recent decades. The most popular modeling technique for latent community detection is the Stochastic Block Model (SBM), which falls into the category of latent variable models and will serve as the baseline model throughout this thesis. SBM is widely regarded as the most effective community detection method as it detects latent community membership …

Application Of Ordinal Regression Models To Acquired Stress Resistance In Wild Strains Of Saccharomyces Cerevisiae, Carson Stacy

Graduate Theses and Dissertations

This thesis explores the application of ordinal regression to the analysis of semi-quantitative growth assays often used when comparing fitness for different strains of the model yeast Saccharomyces cerevisiae. For stress survival assays, yeast stress resistance is measured using an ordered survival score that ranges from 0 (no growth) to 4 (confluent growth). Traditional approaches to analyze this type of data either treats data as a nominal categorical variable or as a continuous numerical variable. These approaches risk loss of information or violation of testing assumptions. In contrast, cumulative logit ordinal regression uses the information contained in the order …

A Multi-Scale Compartmental Model For Glucose Regulation And Diabetes Treatment, Andrew M. Watts

Honors Theses

Glucose is a fundamental energy source for cellular function, and its regulation is critical for maintaining metabolic stability in the human body. Glucose homeostasis is governed by a network of biochemical processes involving multiple organ systems that coordinate glucose production, storage, and uptake. Disruptions in this regulation contribute to metabolic disorders such as diabetes mellitus, underscoring the need for mathematical models that provide a mechanistic understanding of systemic glucose dynamics. Herein, we report a multi-time scale discrete-time dynamical systems model using compartmental difference equations to describe glucose concentrations across key physiological compartments. By quantitatively modeling glucose transport and metabolism, this …

Biomimetic Design Of Mechanochromic Single-Chain Nanoparticle Polymer Networks, Samuel Robinson

Honors Theses

Hydrogels are a class of polymer networks that show promise in many biomedical applications but are typically limited in use due to their brittle nature. Synthesizing hydrogel networks that are comparable to biological materials has long been an area of interest. In this study, we are working to create a polymer network inspired by the muscular protein, titin. Titin can unfold under mechanical tension, releasing stored length, making the muscle material extensible and durable. To mimic this behavior, we propose creating a polymer network with similar stored length using single chain nanoparticles (SCNPs) cross-linked with phenolphthalein (PP) and β-cyclodextrin (β-CD). …

Comparison Of Rt-Qpcr And Rt-Ddpcr On Assessing Model Virus In Wastewater, Wafa Youssfi

Graduate Theses and Dissertations

There is an increasing demand for quantifying viral loads in diverse wastewater systems using polymerase chain reaction (PCR). This study evaluates the performance of two commonly used workflows: reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR) in wastewater. We compared the two methods by measuring the viral ribonucleic acid (RNA) of a model virus Phi6 in samples collected from various treatment stages at the Westside Wastewater Treatment Facility in Fayetteville, AR. RNA was extracted from real and synthetic wastewater samples and analyzed in parallel using both RT-qPCR and RT-ddPCR. Findings reveal that both methods demonstrated similar …

Finer Resolution Paleoclimatological Network Analysis Of Hydrological Extremes And Tree-Growth Response For Kentucky, U.S.A., Jordan Sharp

Electronic Theses and Dissertations

As climate change accelerates, southeastern states like Kentucky face increasing environmental and economic challenges. To improve future climate predictions, this study enhances paleoclimate reconstructions with a high-resolution tree-ring network for Kentucky, combining data from both living trees and dendroarchaeological sources. I evaluated the climate sensitivity of tree growth using superposed epoch analysis, static correlations, and spatial field correlations in KNMI Climate Explorer, along with moving correlations against seasonal temperature and moisture variables. Findings reveal that white oak and tulip poplar exhibit significant drought sensitivity across both live and archeological sites. However, I observed a weakening relationship between tree-ring growth and …

Setting Up Students For Success: Analysis Of Effectiveness For Mathematics Placement, Jeff Carvell, Jason N.E. Ho, Dave Klanderman, Sarah Klanderman

Faculty Work Comprehensive List

How do we effectively and equitably place students into math classes in a way that provides them the best chance of success? As many higher education institutions veer away from placement based on standardized testing, many departments are seeking placement alternatives that will properly support students. Additionally, math placement determines not only a student’s mathematics courses but also influences their progress in related fields, including physics, chemistry, engineering, and more. This paper will describe three different existing placement systems at each of our liberal arts institutions as well as the affordances and constraints of each approach. Further, we analyze data …

Synthetic Efforts Towards An Analog Of Ly426965, Macy Sproles

Honors Theses

The 5-hydroxytryptamine_1A (5-HT_1A) receptor is a key target in the treatment of various neuropsychiatric conditions, and the development of selective antagonists offers promising therapeutic potential.²⁴ This study aimed to develop a synthetic analog of LY426965, a selective 5-HT_1A receptor antagonist. The synthetic route was initiated from dimethyl-2-phenylmalonate, employing pig liver esterase (PLE) as an enantioselective biocatalyst to achieve regioselective hydrolysis of one ester moiety in the malonic diester intermediate.¹⁷ Through a series of stereochemically controlled transformations, a new intermediate was successfully synthesized. Although the target molecule was not obtained, a new compound was synthesized …