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Malnutrition And Frailty Risk Among Community Dwelling Older Adults In Northeast Tennessee, Shreeyesha Pradhan May 2026

Malnutrition And Frailty Risk Among Community Dwelling Older Adults In Northeast Tennessee, Shreeyesha Pradhan

Electronic Theses and Dissertations

Frailty and malnutrition are prevalent conditions among community-dwelling older adults, affecting approximately 10% and 25% of this population, respectively. Despite overlapping symptoms such as functional decline, their relationship remains underexplored in community dwelling older adults. This cross-sectional feasibility study examined the association between frailty and nutritional status among 47 older adults in the East Tennessee Tri-Cities area using the Fried’s Frailty Phenotype (FFP) and the Mini Nutritional Assessment-Long Form (MNA-LF®). Results indicated 13% were pre-frail, 24% were frail, 21% were at risk for malnutrition, and 2% were malnourished. Regression analyses revealed that self-perceived nutritional status (37.6%), daily meal frequency (29.0%), …


Extreme Precipitation Events And Population Exposure: Site Recommendations For The Future Tennessee Mesonet, Victoria G. Redlund May 2026

Extreme Precipitation Events And Population Exposure: Site Recommendations For The Future Tennessee Mesonet, Victoria G. Redlund

Electronic Theses and Dissertations

This study examines frequency of and population exposure to extreme rainfall events in Tennessee to guide the placement of future mesonet weather stations. Using 1991-2021 daily nClimGrid precipitation records, extreme events were defined as events of rainfall ≥50 mm. These events were collated on an annual scale and normalized alongside square-root-scaled population densities derived from Landscan to develop extreme rainfall vulnerability maps. Results highlight where extreme rainfall is most frequent relative to population densities in each county. The findings were compared with models of mesonet suitability and feasibility to determine how meteorological needs correlate with siting needs such as land …


Ontogeny And The Effects Of Perinatal Stress In The First Immature Skeleton Of Teleoceras Aepysoma (Perissodactyla, Rhinocerotidae), Joe Gajewski May 2026

Ontogeny And The Effects Of Perinatal Stress In The First Immature Skeleton Of Teleoceras Aepysoma (Perissodactyla, Rhinocerotidae), Joe Gajewski

Electronic Theses and Dissertations

Recovery of an immature fossil rhinoceros (Teleoceras aepysoma) skeleton (ETMNH 32999) from the Gray Fossil Site in Tennessee offers the first insights into the ontogeny of the species. ETMNH 32999 is interpreted to be a subadult male in an age class equivalent to ~17-20% of potential lifespan. Comparative analyses support the hypothesis that subadults of related taxa are typically ~91% of average adult size in most dimensions. However, certain cranial dimensions are substantially lower than expected in ETMNH 32999, averaging only ~74% of the average conspecific adult. Such departure from typical growth rates is suggested to be attributable …


Utilizing Physics Informed Neural Networks For Disrupted Signal Dynamics, Nicholas J. Joyner May 2026

Utilizing Physics Informed Neural Networks For Disrupted Signal Dynamics, Nicholas J. Joyner

Electronic Theses and Dissertations

Physics-informed neural networks (PINNs) have been used in many applications including engineering and physical sciences. PINNs allow the incorporation of a priori understanding of a process’ structure into the modeling. We attempt to leverage the PINN structure toward the evaluation of disruptions to classical dynamical models by combining elements of ordinary differential equations into our loss function with sigmoidal gating to balance the penalties for deviations from the data with those for structural deviations. This enables the identification of the signal structure and the limits of disruption influence. As a use case, we consider stock value from 2019-2021, which expresses …


Machine-Learning Landslide Susceptibility And Runout Modeling In The Nolichucky River Gorge After Hurricane Helene, Grace Braver May 2026

Machine-Learning Landslide Susceptibility And Runout Modeling In The Nolichucky River Gorge After Hurricane Helene, Grace Braver

Electronic Theses and Dissertations

Extreme rainfall from Hurricane Helene (September 2024) triggered widespread landslides across the southern Appalachian region, highlighting the need for rapid landslide susceptibility assessments that capture both landslide initiation and downstream runout. Traditional susceptibility models often focus solely on initiation zones, limiting their ability to identify which slopes will generate destructive landslides or where material will travel. This study addresses that gap by (1) integrating Geographic Information System (GIS)-based machine learning susceptibility modeling using ArcGIS Pro: Maximum Entropy (MaxEnt) and Random Forest-Based and Boosted Classification and Regression (FBBC) and (2) the U.S. Geological Survey (USGS) Grfin (Growth, Flow, and Inundation) runout …


Mechanism Of Formation Of Guanine-Guanine Crosslinks As Products Of One-Electron Oxidation Of 1-Methylguanosine In Acidic Medium, Ibrahim Braimah Mr May 2026

Mechanism Of Formation Of Guanine-Guanine Crosslinks As Products Of One-Electron Oxidation Of 1-Methylguanosine In Acidic Medium, Ibrahim Braimah Mr

Electronic Theses and Dissertations

Reactive oxygen species (ROS) from normal metabolism and environmental exposure may cause oxidative DNA damage. Guanine (G) is the most oxidizable nucleobase. One-electron oxidation (OEO) of G in produces guanine radical cation (G•⁺), which deprotonates to form guanyl radical G(-H)•.This radical exists in two tautomeric forms: G(N1-H)• and G(N2-H)•. Dimerization of guanyl radical yields G-G cross-links (D1/D2); a tautomeric form for dimer formation remains elusive. This study presents the first characterization of G• dimerization products from the OEO of 1-MeGuo in acidic medium. Photolysis at 470 nm in the presence of S₂O₈²⁻ and Ru(II)(bpy)₃²⁺ generates two major stereoisomers (D1AW* and …


Academic And Demographic Predictors Of Retention And Persistence In Business Programs: Post-Covid Cohorts Of Traditional And Ncccs Transfer Students, Matthew K. Crump May 2026

Academic And Demographic Predictors Of Retention And Persistence In Business Programs: Post-Covid Cohorts Of Traditional And Ncccs Transfer Students, Matthew K. Crump

Electronic Theses and Dissertations

This quantitative study examined academic and demographic predictors of first-year retention and major persistence among traditional first-year and North Carolina community college transfer students enrolled in undergraduate business programs. Guided by Tinto’s 1993 Model of Student Retention and Astin’s 1984 Theory of Student Involvement, the research focused on students who entered two AACSB-accredited institutions within the UNC System during Fall 2021, Fall 2022, and Fall 2023 as traditional first-year students or as transfer students from North Carolina community colleges.

Institutional data from the Banner Student Information System provided the basis for logistic regression analyses that examined predictors including high school …


Durable, Distributed Llm Inference On Cots Devices, Brycen E. Dunn May 2026

Durable, Distributed Llm Inference On Cots Devices, Brycen E. Dunn

Electronic Theses and Dissertations

The advancement of Large Language Models (LLMs) has fundamentally changed the nature of natural language processing. The substantial memory requirements of frontier models creates a significant barrier to entry, centralizing inference. This thesis presents the design and implementation of a distributed inference framework designed to democratize LLMs by leveraging commodity devices. The framework combines the resources of heterogeneous COTS devices into a unified compute pool, enabling the inference of models exceeding a single device's memory capacity. A novel Task Partitioning Engine (TPE) analyzes model architectures, profiles node capabilities, and supports pipeline and expert parallelism strategies. The primary contribution is a …


A Machine Learning Framework For Early-Stage Cost Estimation Of Transportation Projects, Pritom Paul May 2026

A Machine Learning Framework For Early-Stage Cost Estimation Of Transportation Projects, Pritom Paul

Electronic Theses and Dissertations

To address the limitations of traditional planning-level cost estimating methods, such as reliance on statewide averages, heavy reliance on engineering judgment, and high levels of inaccuracy, this study developed two data-driven frameworks and corresponding tools. The first framework focused on resurfacing projects and used treatment-specific simple linear regression based on lane miles and geographic location. The second addressed a broader group of construction projects and used multiple linear regression with project length, route type, and right-of-way cost as key predictors. In both frameworks, the final estimates are computed by aggregating multiple estimates produced by county-, region-, and state-level models. The …


Discrete-Event Simulation: A Leslie System Model For Transportation Demography, Md Zobaer Ahammad May 2026

Discrete-Event Simulation: A Leslie System Model For Transportation Demography, Md Zobaer Ahammad

Electronic Theses and Dissertations

Transportation systems are influenced by demographic change, household formation,and patterns of vehicle ownership. These factors affect long-run transportation demand and congestion levels within urban infrastructure. Understanding how demographic dynamics interact with transportation behavior is therefore important for analyzing the long-term evolution of transportation systems. This thesis develops a modeling framework that integrates discrete-event simulation with a Leslie-type matrix model to study transportation–demography interactions.Simulation outputs are aggregated to construct a transition matrix describing changes in transportation states. This matrix acts as a linear (or affine) transformation on the transportation state vector, allowing the system to be analyzed as a discrete linear …


Post-Vote Tampering In Nigerian Elections And The Role Of Blockchain-Enabled Electoral Systems, Ransome Chukwubuikem Enechukwu May 2026

Post-Vote Tampering In Nigerian Elections And The Role Of Blockchain-Enabled Electoral Systems, Ransome Chukwubuikem Enechukwu

Electronic Theses and Dissertations

Post-vote tampering during the collation and transmission of election results remains a persistent challenge in Nigerian elections, enabling manipulation of already-cast votes and weakening public trust in electoral outcomes. Existing technological interventions, including biometric voter accreditation and digital result transmission systems, improve voter authentication but do not adequately secure the post-vote result collation process. This thesis proposes a blockchain-enabled framework designed to protect the integrity of election results during the collation and transmission stages. Using a Design Science Research methodology, the study develops a permissioned blockchain framework based on Hyperledger Fabric that records polling-unit results as immutable ledger entries and …


Integrated Geophysical, Geotechnical, And Mineralogical Characterization Of Expansive Weches Formation Soils In East Texas: Implications For Infrastructure Design, Samuel Annobil May 2026

Integrated Geophysical, Geotechnical, And Mineralogical Characterization Of Expansive Weches Formation Soils In East Texas: Implications For Infrastructure Design, Samuel Annobil

Electronic Theses and Dissertations

This study investigates the geotechnical, geophysical, and mineralogical characteristics of soils derived from the Weches Formation in Nacogdoches County, East Texas, with emphasis on the relationships among electrical resistivity, moisture condition, compaction state, and mineralogical composition. The Weches Formation is well known for producing clay-rich, moisture-sensitive soils that pose challenges to subgrade performance because of their plasticity and swelling behavior. Representative soil samples were collected and subjected to laboratory testing, including particle size analysis, Atterberg limits, Standard Proctor compaction, free swell tests, electrical resistivity measurements, and X-ray diffraction (XRD) mineralogical analysis. The soils are predominantly fine-grained and clay-rich, with USCS …


The Perceived Barriers Of A One-To-One Technology Implementation: A Post-Covid Case Study, Adam Howard Creasy Apr 2026

The Perceived Barriers Of A One-To-One Technology Implementation: A Post-Covid Case Study, Adam Howard Creasy

Electronic Theses and Dissertations

This qualitative dominant, exploratory sequential case study aimed to identify stakeholder perceptions of technology within a one-to-one technology initiative and outline any possible barriers. The study examined the perceptions of teachers, parents, and administrators within a rural K-12 public school district in Pennsylvania. The study provided school district stakeholders with data they can use to improve existing and future initiatives by early intervention within areas of concern identified by the study. Data were collected using a two round approach which includes focus groups and targeted surveys utilizing research-backed electronic survey tools. The research questions addressed in the study were the …


Staying Power: A Case Study Of Teacher Retention In A Rural District, Amanda F. Mclellan, Amanda F. Mclellan Apr 2026

Staying Power: A Case Study Of Teacher Retention In A Rural District, Amanda F. Mclellan, Amanda F. Mclellan

Electronic Theses and Dissertations

Teacher attrition continues to be a significant challenge in K-12 education, particularly in rural school districts where limited resources and geographic isolation can intensify staffing instability. While much research has focused on teacher attrition, little research examines why tenured teachers choose to remain in rural districts. The purpose of this qualitative, single-case study was to examine the experiences and insights of tenured teachers regarding their decision to continue teaching in a small, rural Texas school district. Guided by Mason and Matas’s fourcapital framework for teacher retention, this study examined how human, social, structural, and positive psychological capital influenced teachers’ decisions …


Architecture As Frozen Music: An Original Wind Ensemble Work Exploring Architectural Metaphors In Contemporary Music, Leighannah J. Turner Apr 2026

Architecture As Frozen Music: An Original Wind Ensemble Work Exploring Architectural Metaphors In Contemporary Music, Leighannah J. Turner

Electronic Theses and Dissertations

Architecture has long served as a source of inspiration for Western art music composers from the Early Renaissance through the Neoclassical period. While the relationship between music and architecture has been widely studied, much of the existing research focuses on traditional mediums such as the symphony orchestra. This project explores the concept of music as “frozen architecture” – introduced by Friedrich Schelling – and the metaphorical correlations as described by Vitruvius and Lupishko, applying these concepts to the contemporary medium of the wind ensemble through my original composition. My work integrates the architectural principles proposed by Vitruvius and Lupishko while …


Addressing The Problems Of Data Variations, Quality, And Scarcity In Training Deep Neural Networks, Jian Sun Mar 2026

Addressing The Problems Of Data Variations, Quality, And Scarcity In Training Deep Neural Networks, Jian Sun

Electronic Theses and Dissertations

The performance of deep neural networks (DNNs) is strongly influenced by the characteristics and quality of the underlying datasets. This Ph.D. dissertation addresses three pervasive data challenges-imbalance, quality degradation, and scarcity-that commonly hinder the effectiveness of DNNs in computer vision (CV) and natural language processing (NLP) applications.

Class imbalance remains one of the most frequent causes of degraded model generalization. While Focal Loss effectively mitigates inter-class imbalance by assigning higher weights to minority classes, it struggles with intra-class imbalance, particularly in video datasets where longer clips dominate feature representation. To address this, I implement and utilize …


Contribution Of G4 Structure To Alzheimer’S Disease And Tau Pathology, Lena Michaela Kallweit Mar 2026

Contribution Of G4 Structure To Alzheimer’S Disease And Tau Pathology, Lena Michaela Kallweit

Electronic Theses and Dissertations

The occurrence of Alzheimer’s Disease (AD) is rapidly increasing as our global population ages. With the majority of therapeutic drugs in the last couple of decades failing clinical trials, new molecular targets are needed to combat the expected influx of new AD cases. AD pathogenesis is associated with abnormal protein aggregation, characterized in part by intracellular accumulation of hyperphosphorylated tau (p-tau) in neurofibrillary tangles (NFTs). RNA has been identified as a major non-proteinaceous component of NFTs and has been implicated as an active cofactor in tau aggregation and spread. Recent work has shown that aggregates from AD brains contain almost …


A Narrative Study On The Resilience Of Women In Technology Careers, Gina J. Baldridge Mar 2026

A Narrative Study On The Resilience Of Women In Technology Careers, Gina J. Baldridge

Electronic Theses and Dissertations

In spite of the promotion of science, technology, engineering, and mathematics (STEM) education and careers, there is a lack of women entering the STEM workforce and majoring in STEM subjects. Women can experience gender bias and workplace marginalization in STEM careers, but have learned coping strategies that have contributed to their technology career resilience. The purpose of this narrative qualitative study was to explore how women working as individual performers and leaders in technology companies told their career stories of resilience through the perspective of change acceptance, confidence, and communication, three factors in Kumar’s CR8 model of resilience. The model …


Exploring The Lived Experiences Of Black Women In Undergraduate Stem Core Expansion Pathways, Lizzie L. Evans Martinez Alvarez Mar 2026

Exploring The Lived Experiences Of Black Women In Undergraduate Stem Core Expansion Pathways, Lizzie L. Evans Martinez Alvarez

Electronic Theses and Dissertations

The use of social incongruence in the film Hidden Figures, which juxtaposed with STEM education as the most powerful in contrast with Black women as the least powerful, supported the argument for the specific problem of practice to examine the unmet need for socially and ethnically diverse student populations in U.S. STEM higher education and careers. The purpose of this hermeneutic phenomenological research study was to identify and analyze the lived experiences of Black women regarding barriers they perceive in the STEM educational and career decision-making processes, while exploring transformational pathways to STEM academic success. The study specifically analyzed …


A Taxonomy-Driven Modular Defense Against Non-Canonical Language In Vision-Language-Action Models, Viraj Samson Jan 2026

A Taxonomy-Driven Modular Defense Against Non-Canonical Language In Vision-Language-Action Models, Viraj Samson

Electronic Theses and Dissertations

Vision-Language-Action (VLA) models have recently achieved strong performance across manipulation benchmarks, but these benchmarks rely on highly templated instructions on which the models are typically fine-tuned, leaving their behavior under realistic language-side perturbation unclear. It remains an open question whether the linguistic flexibility inherited from vision-language pretraining survives this fine-tuning, or whether the resulting policies become narrowly tuned to benchmark phrasing and brittle to the intent-preserving language variation that real users naturally produce. We address this gap with a systematic study of VLA robustness under non-canonical instructions, comprising three components: a structured taxonomy of intent-preserving variations spanning linguistic, orthographic, and …


Data-Driven Optimization Of Memory Effects And Critical Components In Cascading Failure Interaction Networks, Md Farhan Tanvir Jan 2026

Data-Driven Optimization Of Memory Effects And Critical Components In Cascading Failure Interaction Networks, Md Farhan Tanvir

Electronic Theses and Dissertations

Cascading failures are a major concern for modern power systems‚ where a small failure can cascade through the network to create a large blackout. Because such an event could have catastrophic economic and social costs it is important to understand cascading failures‚ how to model them‚ and the possibility of reducing them. In this thesis‚ we develop a data-driven framework based on actual utility outage data to model and reduce cascading failures. The proposed methodology is based on generation-dependent interaction models and in this study interaction matrices obtained from historical outage events are used to describe the interaction between generations. …


Computational Modeling Of Biophysical Transport: Respiratory Drug Delivery And Tissue-Level Physics, Md Tariqul Hossain Jan 2026

Computational Modeling Of Biophysical Transport: Respiratory Drug Delivery And Tissue-Level Physics, Md Tariqul Hossain

Electronic Theses and Dissertations

The nasopharynx, the upper part of the pharynx located at the back of the nose serves as a critical hotspot for initial respiratory infections via inhaled transmission, largely due to the presence of specific surface receptors that pathogens can exploit for cell invasion, combined with a relatively sparse local mucociliary substrate. To enhance the therapeutic efficacy against certain pathogens, such as the SARS and Influenza viruses, it is therefore essential to improve the targeted delivery of drugs to the nasopharynx. This study explores the use of intranasal sprays as a method for drug administration and models the transport of sprayed …


Floodwater Salinity And Flood Duration Regulate Greenhouse Gas Production In High- Latitude Coastal Wetland And Tundra Soils, Mia J. Dicianna Jan 2026

Floodwater Salinity And Flood Duration Regulate Greenhouse Gas Production In High- Latitude Coastal Wetland And Tundra Soils, Mia J. Dicianna

Electronic Theses and Dissertations

Coastal high-latitude ecosystems are increasingly flooded from storm surges associated with climate change, exposing soils that were historically infrequently inundated to higher-salinity waters for longer durations. Sub-Arctic wetlands and tundra store large amounts of carbon, yet how flooding characteristics, particularly flood duration, influence microbial mineralization and, consequently, greenhouse gas (GHG) production in these soils remains poorly understood. We conducted a full-factorial microcosm incubation experiment in which coastal wetland and tundra soils were subjected to simulated flooding with three durations (1, 3, and 10 days) and four salinity treatments (unflooded, freshwater, 3 ppt, and 12 ppt) and measured carbon dioxide (CO2) …


Winter-Feeding High Forage Vs. High Concentrate Diets To Beef Cows: Effects On Placental Transcriptomics, Lactation Capacity, And Enteric Methane Emissions, Megan Ann Wehrbein Jan 2026

Winter-Feeding High Forage Vs. High Concentrate Diets To Beef Cows: Effects On Placental Transcriptomics, Lactation Capacity, And Enteric Methane Emissions, Megan Ann Wehrbein

Electronic Theses and Dissertations

Nutritional management and lactation performance are critical factors influencing productivity in cattle. This research includes two complementary studies. The first study was a meta-analysis to develop a lactation curve for Bos taurus cattle in North America using data from machine or hand milked cows. Data from 7 studies were used resulting in 1340 cow-day observations. Milk yield was analyzed by parity (primiparous or multiparous) and feeding management (non-nutrient restricted or nutrient restricted), revealing that primiparous cattle peaked earlier and at lower yields than multiparous cattle, and nutrient restriction reduced peak milk yield. Overall, Bos taurus cattle followed lactation trends similar …


Semantic Discovery Of Genomic Datasets With Ai, Lawrence Allibah Jan 2026

Semantic Discovery Of Genomic Datasets With Ai, Lawrence Allibah

Electronic Theses and Dissertations

Traditional keyword-based search in genomic databases often fails to capture the latent semantic context of biological studies, leading to a ``Lexical Gap" in research discovery. This thesis presents a high-performance dual-engine discovery system built upon 10,000 studies. By utilizing 1,536-dimensional vector embeddings, with large language models (LLMs) we implement a search engine coupled with a novel Hybrid Boosting layer that integrates semantic intent with factual metadata. Furthermore, we apply a high-dimensional K-Means clustering algorithm for unsupervised topic discovery. Empirical benchmarking demonstrates that the Hybrid Boosting engine achieves a 38.1% gain in precision and a 41.2% increase in Mean Reciprocal Rank …


Effect Of Corn Processing Methods On Growth Performance, Carcass Characteristics, And Gastrointestinal Health In Ruminants Fed Finishing Diets, Reanna Rae Byrnes-Schoen Jan 2026

Effect Of Corn Processing Methods On Growth Performance, Carcass Characteristics, And Gastrointestinal Health In Ruminants Fed Finishing Diets, Reanna Rae Byrnes-Schoen

Electronic Theses and Dissertations

The objective of this work was to evaluate different feed processing techniques and their impacts on growth performance, carcass traits, and gastrointestinal health in ruminant animals fed in confinement during the finishing phase. Two studies were conducted. The first study evaluated the effect of kernel processing high moisture ear corn (HMEC) on growth performance and carcass characteristics of finishing beef steers. The second study used feeder lambs to evaluate the effect of steam-flaking corn in a finishing diet on growth performance, carcass characteristics, and gastrointestinal tract (GIT) health. The results from the first study using steers demonstrated that feeding kernel …


Impacts Of Management Practices And Soil Properties On Free-Living Nitrogen Fixation In Eastern South Dakota, Laura Galvan Nuevo Jan 2026

Impacts Of Management Practices And Soil Properties On Free-Living Nitrogen Fixation In Eastern South Dakota, Laura Galvan Nuevo

Electronic Theses and Dissertations

Free-living nitrogen (N) fixation (FLNF) may represent a sustainable pathway to supplement crop N demand in agroecosystems, yet edaphic and management factors regulating this process under field conditions remain poorly understood in the Northern Great Plains. Using 15N2 direct method to quantify potential FLNF (pFLNF) and baseline FLNF (bFLNF), this thesis investigates how crop rotations (2-, 3-, and 4-year systems), tillage management (conventional vs. no-till), cover cropping, and soil properties affect the potential of free-living diazotrophs to supply N via FLNF in a long-term no-till corn-based system in Southeastern South Dakota. A two-year field study evaluated pFLNF across four growing …


Some Applications Of Derivatives In The Theory Of Equations, Commodore C. Dearman Jr Jan 2026

Some Applications Of Derivatives In The Theory Of Equations, Commodore C. Dearman Jr

Electronic Theses and Dissertations

No abstract provided.


Towards Optimal And Resilient Ac/Dc Microgrids: Control Design, Analysis, And Implementation, Jun Zhang Jan 2026

Towards Optimal And Resilient Ac/Dc Microgrids: Control Design, Analysis, And Implementation, Jun Zhang

Electronic Theses and Dissertations

Microgrids serve as a small-scale power grid for utilizing renewable energy to enhance energy reliability, sustainability, and resilience. As an autonomous system, an islanded microgrid can disconnect from the utility grid and operate independently by maintaining system voltage and frequency. However, this new feature introduces coordination problems among distributed generators (DGs), such as 1) how to make sure the voltage profile and current sharing in DC microgrid with different types of converters; 2) how to reduce the impact of cyberattack when the system coordination is performed based on communication, and 3) how to calculate the steady state under a droop …


Development And Application Of Lc-Ms/Ms Methods For The Determination Of Environmental Contaminants, Mawuli Wilson-Cee Macdonald Jan 2026

Development And Application Of Lc-Ms/Ms Methods For The Determination Of Environmental Contaminants, Mawuli Wilson-Cee Macdonald

Electronic Theses and Dissertations

Environmental contaminants such as neonicotinoids and bisphenols are increasingly detected at ultratrace concentrations in environmental and consumer matrices, necessitating sensitive and efficient analytical methodologies. This dissertation presents the development, validation, and application of liquid chromatography–tandem mass spectrometry (LC–MS/MS) methods coupled with simplified sample preparation techniques. In Chapter 2, a direct aqueous injection (DAI) LC–MS/MS method was developed for the analysis of five neonicotinoids in surface water, eliminating extensive sample preparation. The method demonstrated strong linearity (R² = 0.993–0.998), with limits of detection (LOD) ranging from 0.5 to 4 ng/L and lower limits of quantification (LLOQ) of 10–50 ng/L. Accuracy (80–120%) …