Digital Commons Network^™

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%) …

Impact Of Water Level Fluctuations On Fish Populations In Eastern South Dakota Rivers, Benjamin Schall

Electronic Theses and Dissertations

Riverine systems are highly dynamic, and changes in flow conditions can impact the population dynamics of fishes. Increased flows from historical averages in eastern South Dakota rivers have likely impacted fish populations. The goals of this study were to 1) better understand the changes in resource use by Blue Suckers Cycleptus elongatus through retrospective eye lens stable isotope analysis, 2) determine the effects of record flooding in the James River on complex woody habitat and Flathead Catfish Pylodictis olivaris population structure, and 3) assess the influence of river discharge and temperature on Channel Catfish Ictalurus punctatus and Flathead Catfish condition …

Modeling Heterogeneous Trajectories Of Chronic Kidney Disease Progression With Finite Mixture Models Using The All Of Us Dataset, Yahaya Mumuni Musah

Electronic Theses and Dissertations

Background: Chronic kidney disease (CKD) does not progress uniformly across patients, and a single average trajectory often fails to capture this heterogeneity. Understanding variation in disease progression is important for improving risk stratification and clinical management. 
Objectives: This study aims to characterize the heterogeneity of chronic kidney disease (CKD) progression using longitudinal estimated glomerular filtration rate (eGFR) data and to identify factors associated with distinct progression trajectory patterns. 
Methods: A longitudinal cohort study was conducted using data from the All of Us} Research Program collected between April 23, 2002, and October 1, 2023. Adult participants with repeated eGFR measurements were …

Enzyme Susceptibility And Functionality Of High Protein Retentates And Reconstituted Ingredients, Khushi Dubey

Electronic Theses and Dissertations

This thesis explores the effects of processing history on the enzymatic susceptibility and functional properties of high-protein dairy ingredients, with a specific focus on ultrafiltered (UF) and microfiltered (MF) retentates and spray-dried powders. While retentates and powders are often used interchangeably in industrial applications, processing steps, such as drying, can induce structural and physicochemical changes that affect protein functionality and enzyme accessibility. Milk protein concentrates (MPC) and micellar casein concentrates (MCC) were standardized to 10% protein and subjected to enzymatic treatments, including proteolysis (Alcalase and rennet) and crosslinking (transglutaminase and laccase). Structural modifications were evaluated using capillary gel electrophoresis, non-protein …

Butting Heads With Respiratory Disease: Post-Epizootic Demography And Movement-Driven Spillover Risk In A Badland’S Bighorn Sheep (Ovis Canadensis) Meta-Population, Sean P. Ryder

Electronic Theses and Dissertations

Respiratory disease caused by Mycoplasma ovipneumoniae is among the most significant threats to bighorn sheep (Ovis canadensis) conservation in North America. In July 2021, contact between bighorn sheep rams and domestic sheep north of Badlands National Park (BADL), South Dakota, USA introduced M. ovipneumoniae into the Badlands bighorn sheep meta-population, triggering an epizootic that reduced the population by approximately 80%. I evaluated the post-outbreak status of this population through two complementary studies conducted from 2023 to 2025. In Chapter 1, I quantified disease prevalence, adult survival, lamb recruitment, and population growth rate (λ) using serial quantitative polymerase chain reaction (qPCR) …

Improving Human Dimensions Of Conservation Planning: Challenges And Opportunities For Sustainable Conservation Outcomes, Vivian Hulugh

Electronic Theses and Dissertations

Conservation planning is important to ensure both ecological and social benefits of natural resources, including the maintenance of functional ecosystems and stable wildlife populations as well as the provision of resources that communities rely on. Yet, the integration of the human dimensions of conservation planning remains limited in practice. This thesis examines conservation planning in South Dakota and within Joint Venture (JV) partnerships, using qualitative methods to identify challenges and opportunities for more effective and coordinated planning. In chapter one, I examine how collaboration, public participation, and the use of climate information are integrated conservation planning in South Dakota and …

Fast And Sustainable Video Anomaly Detection With Continual Learning, Preethi Amasa

Electronic Theses and Dissertations

Real-time video anomaly detection systems deployed in surveillance, healthcare, and industrial environments face continuous distribution shifts in lighting, viewpoint, and activity patterns. Existing models often experience performance degradation under these conditions and may suffer catastrophic forgetting when adapting to new environments. This thesis proposes RegiGrow, a parameter-efficient continual adaptation framework built on the Flashback retrieval pipeline. RegiGrow integrates Mixture-of-Experts Low-Rank Adaptation into a frozen ImageBind encoder, enabling sequential domain adaptation without modifying the pretrained backbone. A lightweight router maps visual regime features to a distribution over LoRA experts, each specializing in a distinct normal operating regime. The central contribution is …

Towards Energy Access For All: Developing The Lived Energy Experience Index (Leei), Kentina Annie Ishimwe

Electronic Theses and Dissertations

Energy is the fuel that powers the engine of civilization. Energy access metrics ensure that nations continuously work towards providing access for all. However, the prevalent binary indicator fails to consider that energy needs to be usable, accessible, affordable, and reliable. As a result, numerous tiered and multidimensional metrics, such as the Multi-Tier Framework, came about to bridge the gap but proved to be complex and complicated to implement. This study presents the existing literature review, assesses the limitations of current energy access measurement frameworks, and compares household energy needs with reported access statistics. Based on the findings, the Lived …

Sustainable State: A Location-Based Analysis Of Recycling Habits On A University Campus, Valentyna Labrie

Electronic Theses and Dissertations

Universities are mini communities for the younger generation. Their role in advancing sustainable waste management practices is very valuable. That is why it is crucial to promote pro-environmental behavior, monitor consistent sorting accuracy, and maintain positive recycling indicators such as contamination and diversion rates. The research aim was to explore the impact of spatial context and visual communication strategies on recycling accuracy, contamination, and diversion rates at South Dakota State University (SDSU). The research analysed the impact of proximity to food service areas on waste composition. Another research interest was the impact of educational signage and stickers on recycling behavior …

Finite Mixture Modeling Towards Applications In Material Science And Biomedical Data, Jason Hasse

Electronic Theses and Dissertations

This dissertation contains three chapters on different applications of mixture regression models, broadly in materials science and public health. We begin with a basic application of finite mixture models and regression mixture models. The materials science analysis was performed entirely using data from finite element simulations of the additive manufacturing process via powder bed fusion. Visualization of the clustering solution as applied to the additive manufacturing designs highlighted the intuitive patterns that could be found. These patterns simultaneously yield the regression coefficients and subgroups of the geometric regions, providing a way to predict stresses and strains in a new geometry …

Detecting Poisoning Attacks In The Rag Systems Using Multi-Tier Anomaly Detection, Somtochukwu Orizu

Electronic Theses and Dissertations

Retrieval-Augmented Generation (RAG) systems aim to enhance the capabilities of language models by retrieving external knowledge during inference. However, the process of retrieving knowledge introduces new security vulnerabilities to these models, specifically through the possibility of retrieval poisoning attacks in which adversarial documents are added to the system knowledge base to poison the language model’s responses. Although there have been a variety of defenses proposed for retrieval poisoning attacks, limited work has been done in the area of anomaly detection in embedding spaces as a general defense against multiple retrieval poisoning attack strategies. This thesis investigates two embedding-space anomaly detection …

Demographic Impact And Diagnostic Evaluation Of Mycoplasma Ovipneumoniae In Bighorn Sheep Of The Pine Ridge Badlands, Jeffrey Tillery

Electronic Theses and Dissertations

Mycoplasma ovipneumoniae (M. ovi) decimates bighorn sheep (Ovis canadensis) populations through acute die-offs followed by years or decades of failed lamb recruitment. Test-and-remove management has emerged as the primary intervention to restore population growth, and this thesis quantifies the demographic costs of endemic M. ovi infection and evaluates the diagnostic tools upon which this strategy depends. I quantified vital rates across five bighorn sheep subherds (four infected, one uninfected) on the Pine Ridge Reservation (2023–2025), supplemented by pre-outbreak data (2017–2018) from the North Unit of Badlands National Park. Infected subherds declined (λ = 0.965, 95% CrI: 0.813–1.039) while the uninfected …

Securing Smart Agriculture With Communication-Efficient Federated Unlearning, Ujjwal Pudasaini

Electronic Theses and Dissertations

This thesis addresses the data poisoning attack in smart agricultural systems using federated unlearning, where the contribution of compromised field devices must be removed from the global model under communication constraints. We propose FedSCAN, a three-phase framework that identifies critical layers based on parameter sensitivity, classifies active neurons within these layers through relative weight change analysis, and performs unlearning via sparse low-rank adaptation to active neurons while freezing base model parameters. FedSCAN limits computational overhead to a compact parameter subset, enabling devices to participate in a communication-efficient manner. Experimental results on four datasets demonstrate that FedSCAN achieves up to 426.3× …

Ai-Assisted Wheat Spike And Spikelet Detection And Density Mapping Using Multiscale Remote Sensing Data To Support Wheat Grain Yield Forecasting, Hillson Ghimire

Electronic Theses and Dissertations

Wheat grain yield is determined by the number of spikes per unit area, the number of grains per spike, and kernel weight. However, spike number and spikelets per spike are still measured predominantly through manual counting, a labor-intensive and subjective process that limits phenotyping throughput and selection intensity in modern wheat breeding programs. This thesis develops and evaluates a deep learning framework for automated, high-throughput phenotyping of wheat spike and spikelet traits across complementary imaging scales and implements the framework as a deployable platform. First, two large-scale benchmark datasets with oriented bounding box (OBB) annotations were established, comprising 48,521 spike …

Plant-Insect Interactions In Great Plains Restoration And Invasion Ecology, Joseph H. Cammarano

Electronic Theses and Dissertations

Prairie ecosystem loss and invasive plant species are major ecological problems in the Great Plains. Plant-insect interactions have important consequences for both the restoration of prairie ecosystems and management of invasive plant species. Pollinating insects are vital to the sustainability of prairie ecosystems, and herbivorous insects can provide biological control of invasive plant species. Understanding how restoration strategies may influence potential pollinator communities can have important consequences for restoration sustainability and success and understanding how biological control strategies may help manage invasive plant populations can also help land managers reach restoration and conservation goals. In Ch. 2, I sought to …

Data-Driven Decision-Making Frameworks For Energy Procurement And Dynamic Pricing In Electric Vehicle Charging Networks, Pallavi Khanal

Electronic Theses and Dissertations

The continued growth of electric vehicles (EVs) is increasing the demand for charging infrastructure and creating new operational challenges for charging network operators (CNOs). Uncertainty in charging demand, electricity market prices, and user charging behavior can significantly impact both the economic performance and reliability of charging network operations. To address these challenges, this thesis develops an integrated data-driven framework that combines charging demand modeling, risk-aware energy procurement, machine learning, and reinforcement learning for intelligent EV charging network operation. The research begins by developing queueing-based models to characterize EV charging demand under time-varying and stochastic arrival conditions. Time-varying Mt/M/1 and Mt/M/c …

Spatio-Temporal Demand Forecasting For Optimizing Electric Vehicle Charging Network Operations, Subhamyu Mani Nepal

Electronic Theses and Dissertations

The primary objective of this thesis is to create a framework for modeling, forecasting Electric Vehicle load demand and optimizing the EV charging network operation for Charging network operators. As EV’s popularity grows accurate forecasting of EV charging demand and its effect on the distribution network is critical for the efficient planning and operation of charging infrastructure, as well as for enabling Charging Network Operators to participate effectively in wholesale electricity markets. The first part of the work develops Mt /M/1 & Mt /M/c queuing models calibrated using real-world EV charging data to characterize station-level operations under time-varying arrival rates. …

Effect Of Female Employment On Household Expenditure In Bangladesh, Fatema Binte Sharif

Electronic Theses and Dissertations

Female labor force participation (FLFP) in Bangladesh has increased from 29.2% in 2005–06 to 42.8% in 2022, raising important questions about household resource allocation. This study examines the impact of female employment on household expenditure patterns and challenges the traditional unitary model of decision-making. It focuses on how income controlled by women influences spending across essential and non-essential categories. The analysis uses data from the Household Income and Expenditure Survey (HIES) conducted by the Bangladesh Bureau of Statistics. This research employs Seemingly Unrelated Regression (SURE) approach to estimate budget shares for food, housing, health, education, clothing, and transport. The study …

Finding Value In Professional Learning: Developing Teacher Learning That Is Internalized And Implemented In Practice, Stephanie Dossett

Electronic Theses and Dissertations

Abstract

This study was designed after the researcher engaged in multiple mandated professional learning experiences with faculty members who expressed dissatisfaction with their learning experiences, did not desire to engage in learning on the mandated topics, and wanted to engage in different types of learning opportunities. The problem was centered around dissatisfaction with professional learning among teachers and the lack of implementation of their professional learning in the classroom. The goal was to gather feedback that could help leaders design mandated learning for teachers that they would find satisfaction in and implement in their classroom. The study used semistructured qualitative …

Assistant Principals’ Perspectives And Experiences Concerning Their Influence As Instructional Leaders On Student Achievement In Title I Schools, Courtney J. Charles

Electronic Theses and Dissertations

Abstract

This qualitative descriptive study explored the perspectives and experiences of assistant principals in Title I schools in the context of their instructional leadership responsibilities. The study examined the relationship between assistant principals as instructional leaders in Title I schools and student achievement by addressing research questions related to curriculum implementation, data-driven decisions, school culture, instructional support, and professional development. Moreover, this study used purposeful sampling to select 13 assistant principals from Title I schools, and data were collected through semistructured interviews and analyzed using thematic analysis. Marzano’s focused school leader evaluation model served as the framework for interview questions. …

The Lived Experience Of Special Education Director Retention: A Phenomenological Study Of Motivational And Organizational Influences, Matthew R. Taylor

Electronic Theses and Dissertations

The stability of leadership in special education is crucial for ensuring regulatory compliance, programmatic quality, and equitable services for students with disabilities. However, U.S. public schools face persistent challenges in retaining special education directors, resulting in a loss of institutional knowledge, service fragmentation, and increased risk of compliance failure. Drawing on self-determination theory and job embeddedness theory, this phenomenological study explored the intrinsic and extrinsic aspects that influence special education directors’ decisions to remain in their roles. Ten experienced special education directors from diverse public school settings in Texas participated in semistructured interviews and follow-up quantitative questionnaires. The analysis revealed …

The Impact Of Synchronous And Asynchronous Preference On The Performance Of Distance Learning Students, Christopher A. Wilson

Electronic Theses and Dissertations

Distance learning is a growing part of education. The transition to distance learning was underway at higher education institutions, but the COVID-19 pandemic forced institutions of all types to rapidly transition to distance learning. The technology that was adapted during this emergency distance learning remained in the classroom once normal instruction resumed. This quantitative study examined two aspects of distance learning technology in education. The study examined student preference for either synchronous or asynchronous instruction through the framework of expectancy theory. Students who were more familiar with the course material were hypothesized to have a higher expectation of success and …

Accessing Campus Mental Health Services In A Nigerian Southwestern University: Barriers To Academic Success, Caroline Dada

Electronic Theses and Dissertations

Mental health disorders are a significant health concern among higher education institutions in sub-Saharan Africa, including Nigeria. A substantial treatment gap exists in the Nigerian healthcare system, and this gap is further worsened by cultural and religious barriers, which reinforce stigma that discourages students from seeking professional help. This qualitative narrative inquiry explored the barriers students encountered when accessing mental health services at a university in Southwestern Nigeria, to increase service access. Qualitative semistructured interviews were conducted with seven professional mental health providers at a university counseling center between March and April 2025. Inductive thematic analysis was used to identify …

Building Relationships: Does Perceived Counselor Cultural Humility Improve Client Satisfaction Of Mental Health Services Within Therapeutic Dyads Of Dissimilar Identities?, Noah Schoch

Electronic Theses and Dissertations

A wealth of clinical research has uncovered the presence of mental health treatment disparities and a lack of treatment consistency when working with clients of dissimilar identities. The purpose of this dissertation study was to investigate potential causes for the observed disparities minoritized individuals have experienced and understand if cultural humility was a variable that affected mental health treatment satisfaction when counselor-client had dissimilar cultural identities. This was achieved through the following research questions: (1) What is the relationship between the extent of client perceived racial/ethnic similarity within the therapeutic dyad and client-rated mental health treatment satisfaction? (2) What is …

Examining The Effects Of Video Modeling To Enhance Culturally Specific Social Greeting Skills In Preschoolers With Asd In Saudi Arabia, Sarah Alzahrani

Electronic Theses and Dissertations

A lack of social communication skills, including initiation and responding, has been a prominent characteristic of children diagnosed with ASD (Kanner, 1943; Kroeger et al., 2007). Enhancing these skills in children with ASD during early childhood is crucial to their future relationships, friendships, participation in communal activities, and overall lowering the likelihood of adverse long-term effects, giving significance to this age as a pivotal period for enhancing various skills (Hart Barnett, 2018). Failure to provide interventions to address social communication in children with ASD, specifically in cultures that value this skill, can impede their integration into that society. Thus, this …

The Marathon: A Qualitative Exploration Of The Lived Experiences Of Black Male Educators, Lloyd M. Cheatom Sr

Electronic Theses and Dissertations

Utilizing a culturally relevant framework and methodology, this qualitative dissertation proposal aims to explore and investigate the unique life experiences and exposures that influence Black men to not only become educators but to sustain their careers in the educational field. The purpose of this study is to identify ways in which 1Nation Mentoring can organically implement strategic opportunities that replicate experiences capable of inspiring interest among young Black males to pursue meaningful roles within education and foster a pipeline of future Black male educators.

Additionally, this research will examine the intersection between education and trauma-based experiences, as well as the …

Mind The Gap: Intergenerational Perspectives On Mental Illness Within Ghanaian American Communities, Ama Danso-Ayesu

Electronic Theses and Dissertations

This research explores attitudes toward mental illness among Ghanaian immigrants and

first-generation Ghanaian Americans, with particular focus on factors that influence

stigma. Guided by Bronfenbrenner’s Bioecological Model, the study utilized the

Community Attitudes Toward Mental Illness (CAMI) Scale to measure four dimensions

of stigma, including authoritarianism, benevolence, social restrictiveness, and community

mental health ideology. A comparative, cross-sectional design was employed to examine

differences between immigrant and American-born participants. The findings revealed

generational differences where Ghanaian immigrants reported higher levels of

authoritarian and socially restrictive beliefs, while first-generation Ghanaian Americans

demonstrated more benevolent and inclusive attitudes. Interpreted through the ecological

systems …

Likes For Love: Examining The Relationship Of Sociocultural Factors On Social Media Influences Of Instagram Use For Young Black Women, Cheria S. Jackson

Electronic Theses and Dissertations

In recent years there has been a push toward studying ethnic minority women related to the psychological implications of image and beauty, as historically the focus has been on the experiences of European women (Awad et al., 2015). Black women must process sexual development, attitudes, and behaviors through the lens of the sexual scripts and stereotypes of their ethnic group and must negotiate between mainstream and culture specific norms of sexuality (Daniels and Zurbriggen, 2016; Jerald et al., 2017). The presence of these scripts signifies a difference between Black women and other races about how they may internalize and react …

Counselor Perspectives On Substance Use Treatment In Pennsylvania As Medical Cannabis Laws Evolve, Renee L. Ludwig

Electronic Theses and Dissertations

Cannabis, once primarily regarded as a recreational or “party” drug, has undergone a significant shift in public and medical perception over the past two decades. It is now increasingly recognized as a therapeutic agent prescribed within clinical settings. While substantial research has examined the general use of medical cannabis, relatively little attention has been given to its implications for substance use counselors treating clients who use medical cannabis during treatment for substance use disorders. The purpose of this study is to explore the perceptions of substance use counselors regarding client use of medical cannabis and to investigate how such use …

Charter School Counselor's Perceived Barriers To Implementing A Recognized Asca Model Program, Nadene P. Pomerico

Electronic Theses and Dissertations

In 2003, the American School Counselor Association published its first edition of the ASCA National Model—a framework for school counselors to develop and implement comprehensive school counseling programming. This streamlined guidance supports school counselors in developing and implementing comprehensive school counseling programming that prioritizes services to students with systematic intentionality. In addition, the American School Counselor Association released the Recognized ASCA Model Program (RAMP) award. This distinction is awarded to school counseling programs that demonstrate the implementation of the ASCA National Model with fidelity, which includes using data to evaluate the impact of school counseling programming. Through the years, a …