Digital Commons Network^™

Comparing The Effect Of Marine Aquarium Salts And Sodium Chloride On Vicia Faba Stress Response, Bethany Smerdon

The Plymouth Student Scientist

Soil salinity is a major abiotic stressor limiting agricultural productivity. Many salt stress studies rely solely on sodium chloride (NaCl) solutions, despite not accurately representing natural saline conditions. This study investigated the stress response of Vicia faba to NaCl and marine aquarium salt (MAS) solutions to assess the impact of a more complex ionic composition on plant physiology. Plants were cultivated in a controlled greenhouse and treated with either NaCl, MAS, or rainwater (control) for up to 55 days. Growth parameters, water status, proline accumulation, chlorophyll content, and root nodule weight were measured to evaluate stress responses. The results indicate …

Evaluating The Impacts Of The Invasive Macrophyte, Crassula Helmsii, On Macroinvertebrate Assemblages At Small Spatial Scales In Lentic Ecosystems, Keivan Rakhshani

The Plymouth Student Scientist

Freshwater ecosystems cover only three percent of the Earth’s surface yet support approximately ten percent of global biodiversity. These systems play a crucial role in maintaining native biodiversity across spatial and temporal scales but are increasingly threatened by anthropogenic stressors, including habitat modification, pollution, and biological invasions. The introduction of non-native macrophytes can fundamentally alter community structure by modifying habitat complexity, resource availability, and competitive interactions. This study assesses the impact of the invasive macrophyte Crassula helmsii on macroinvertebrate assemblages at small spatial scales within partially invaded ponds in Dartmoor National Park, southwest England. Three ponds with varying degrees of …

Assessing Jasmonic Acid Seed Priming In Brassica Napus: Impacts On Aphid Herbivory Resistance And Seedling Fitness Trade-Offs, Daisy Stradling

The Plymouth Student Scientist

Jasmonic acid (JA) is a key phytohormone involved in plant defence, offering a potential sustainable alternative to conventional chemical pesticides. While JA seed priming has been explored as a strategy to enhance herbivore resistance in certain plant families, its potential fitness trade-offs remain poorly understood. This study investigates the effects of JA seed priming on Brassica napus (oilseed rape), a key agricultural crop, focusing on seedling fitness and resistance to Brevicoryne brassicae (mealy cabbage aphid), a major agricultural pest. To assess potential fitness trade-offs, seeds were primed with 75 µM JA, and multiple seedling fitness parameters were measured. Germination monitoring …

The Lived Experience Of Uk Students Transitioning To University With Type 1 Diabetes Mellitus, Emelia C. Steel

The Plymouth Student Scientist

Transitioning from secondary school to university is a high-risk period for managing type 1 diabetes among UK students. Canadian research identified limited systemic support during this period. However, there is a lack of qualitative insight into how students navigate this transition in the UK, where healthcare and education systems differ. This study addressed that gap through semi-structured interviews to understand what makes this transition particularly challenging and what support students would find most helpful. A purposive sample comprised seven participants aged 19–29 from four UK universities. Thematic analysis, guided by Braun and Clarke’s (2022) six-phase framework, identified three superordinate themes: …

Investigating Deception-Related Moral Conflict Using Electroencephalography (Eeg) Hyperscanning, Madie Ades

The Plymouth Student Scientist

Amplitudes of the early Bereitschaftspotential (BP) and deceptive behaviour have been theorised to be modulated by moral conflict experienced when making deceptive decisions, as the decision to lie can depend upon our moral perceptions of what is right and wrong (Panasiti et al., 2014). However, most Electroencephalography (EEG) deception paradigms lack ecological validity by utilising instructed lying and failing to incorporate genuine social interaction (Ganis & Keenan, 2009) and therefore may fail to elicit genuine moral conflict. The present study combined hyperscanning EEG with a competitive two-player social game, where participants freely chose to respond accurately or deceptively for …

Exploring Factors That Contribute To The Success Of Latina Superintendents In South Texas, Juanita D. Ybarra-Rodriguez

Theses and Dissertations

The COVID 19 pandemic brought forth many new challenges to the K-12 public schools. Superintendent turnover rates reached concerning levels in Texas and nationwide. This study explored the relationships between Latina superintendent’s success and the superintendents’ experiences with the school board, the community, their own health and safety and experiences related to maintaining superintendents’ role. Success is defined as a participant who acquired the superintendent role and maintained it for at least three years. Participants in this study were selected from Hispanic female superintendents within the Region One Education Service Center (ESC) in South Texas who had acquired and remained …

Deep Community Engagement: Faculty Responsiveness Perspectives At A Hispanic Serving Institution, Joseph Coppola

Theses and Dissertations

This qualitative, narrative inquiry investigates how experienced faculty members embody and enact responsive pedagogical practices at a community college Hispanic-Serving Institution (HSI). Despite generational poverty and low degree attainment among Latine students, institutions face mounting pressure from deficit-mindedness and political mandates that threaten educational equity and resources for HSIs. This research sought to answer: How do community college faculty teaching at a Hispanic Serving Institution exhibit attributes of responsiveness?

The theoretical framework utilized the core tenets of Paulo Freire’s critical pedagogy and integrated models from Gloria Ladson-Billings (culturally relevant pedagogy), Geneva Gay (culturally responsive teaching), Django Paris (culturally sustaining pedagogy), …

The Lived Experiences Of School Counselors, Job Burnout, And The Blurred Lines Of The Profession, Cecilia Angelica Gomez

Theses and Dissertations

This phenomenological qualitative study explores the lived experiences of school counselors during and after the COVID-19 pandemic, focusing on job burnout, role ambiguity, and the blurred lines of the profession. Through semi-structured interviews with practicing school counselors, the study identifies common themes including role overload, manifestations of burnout, coping and resilience strategies, and the impact of administrative support. Findings highlight the systemic factors contributing to counselor stress and the importance of self-care, peer collaboration, and role clarity for counselor well-being and student outcomes.

The Influence Mechanism Of Chief Sustainability Officers On Firm Sustainability Performance, Taiwo Abraham

Theses and Dissertations

This dissertation examines how Chief Sustainability Officer (CSO) human capital configurations influence organizational sustainability performance through a configurational approach. Drawing on Upper Echelons and Human Capital theories, the study conceptualizes CSO human capital as encompassing both general (GHC) and sustainability-specific (SHC) dimensions that interact with job functions and governance mechanisms to shape outcomes. The theoretical framework proposes that SHC primarily influences non-financial sustainability performance (nfSP), while GHC drives financial sustainability performance (fSP). Champion functions moderate the SHC-nfSP relationship, while Ambassador functions moderate the GHC-fSP relationship. Firm sustainability governance further enhances these relationships and creates pathways for SHC to influence financial …

Navigating Cultural And Professional Identities: A Study Of Hispanic Women's Experiences In Aerospace Internship Programs, Jennifer Becerra

Theses and Dissertations

This phenomenological study investigated how Hispanic women navigated cultural identity and professional development during National Aeronautics and Space Administration (NASA) internship programs, examining the role of culturally responsive mentoring in supporting retention. The research question was, How do Hispanic women in aerospace-internship programs navigate the intersection of cultural identity and professional development as they transition from academic science, technology, engineering, and mathematics (STEM) programs to aerospace careers, and what role does culturally responsive mentoring play in supporting their retention?

Using Anzaldúa’s nepantla concept, Duncan-Andrade’s critical-hope theory, and Ladson-Billings’ culturally relevant pedagogy as theoretical frameworks, in this study, I employed semistructured …

Determination Of An Effective Natural Boxelder Bug (Boisea Trivittata) Repellent, Reyna Chavez

Theses and Dissertations

This study investigates the use of ecofriendly repellant alternatives to pest management to control boxelder bugs (Boisea trivittata). This bug gathers by the thousands on warm surfaces of exterior suburban homes during early fall and late spring. I determined bug repellency to turmeric oil (Curcuma longa), catnip (Nepeta cataria), citronella (Cymbopogon nardus), and lavender (Lavandula angustifolia). The treatments consisted of essential oils containing 20% methanol. All treatments demonstrated repellency of Boxelder bugs. Citronella was the most effective and had the highest level of repellency range of 90-99%. Catnip was the least effective with a repellency range of 63-82%.

A Picture Tells A Thousand Words—, But Ecg Signals Have More To Say, Ashley N. Gomez

Theses and Dissertations

With the increasing adoption of deep learning classification models in the medical domain, a critical challenge remains: achieving high predictive accuracy while maintaining clinical Inter-pretability. This study examines how model architecture, dataset origin, and the use of full versus subset data affect both classification performance and Interpretability in Electrocardiogram (ECG) signal analysis. ResNet18 is evaluated using an open-source ECG Image Dataset, thus a custom dataset derived from digitized ECG images. Post-hoc explainability methods, such as Integrated Gradients, are applied to determine which time steps have the most significant influence on model decisions. The findings demonstrate that model architecture and dataset …

Efficient Self-Supervised Representation Learning For Large-Scale Time Series Classification, Kevin Garcia

Theses and Dissertations

Recently, there has been a significant advancement in designing Self-Supervised Learning (SSL) frameworks for time series data to reduce the dependency on data labels. Among these works, hierarchical contrastive learning-based SSL frameworks, which learn representations by contrasting data embeddings at multiple resolutions, have gained considerable attention. Due to their ability to gather more information, they exhibit better generalization in various downstream tasks. However, when the time series data length is significant long, the computational cost is often significantly higher than that of other SSL frameworks. In this paper, to address this challenge, we propose an efficient way to train hierarchical …

Interpretable Alignment Of Textual Weather Reports With Local Sensor Time Series For Extreme Weather Event Visualization, Juan Luis Garza

Theses and Dissertations

This thesis presents an automated and interpretable pipeline that links natural-language weather narratives with local meteorological sensor time series. Using large language models, NOAA-style event reports are transformed into structured records capturing event type, timing, descriptive context, and uncertainty. Each extracted event is aligned with harmonized temperature, precipitation, and wind measurements from nearby weather stations, enabling systematic comparisons between narrative evidence and observed atmospheric conditions.

Across roughly fifty stations and more than two thousand events, the analyses show that discrepancies between narrative descriptions and sensor behavior arise primarily from spatial separation rather than from temporal offsets, sensor preprocessing artifacts, or …

Ai-Driven Electromagnetic Design And Performance Prediction Of Microstrip Antennas, Eduardo Javier Vazquez

Theses and Dissertations

This thesis investigates the application of Deep Learning to automate and accelerate microstrip antenna inverse design. The initial investigation was to predict microstrip antenna performance from its geometry parametric input, and found out that forward prediction with adopted geometric representation results in ill-posed scenario, high ambiguity and unstable mapping. The study later mostly focuses on the inverse prediction by machine learning from S11 parameter input to predict antenna patch geometry parameters instead.

A dataset of 5,000 ANSYS HFSS simulated antennas (later filtered to 4,136 valid samples) was generated using cubic spine -described geometry profiles. Multiple neural architectures were adopted for …

Seagrass Preference Among Pinfish In The Lower Laguna Madre, Nathaniel Garza

Theses and Dissertations

Pinfish (Lagodon rhomboides) is a common estuarine fish species found from Massachusetts to the Yucatan, Mexico. As juveniles, pinfish spend a significant portion of their life in coastal seagrasses which provide both shelter from predators and food. Along the Texas coast, there are three major species of seagrass- turtle grass (Thalassia testudinum), manatee grass (Syringodium filiforme) and shoal grass (Halodule wrightii) that differ in structural complexity. The goal of this study was to determine if pinfish associate more with one seagrass species than the others. A year-long field study was completed using twelve sample sites in the Lower Laguna Madre, …

Bacillus Subtilis: A Bacterium That Can Potentially Degrade Low-Density Polyethylene (Ldpe) And Polyethylene Terephthalate (Pet), Migdalia Flores

Theses and Dissertations

The widespread application and disposal of plastics, such as low-density polyethylene (LDPE) and polyethylene terephthalate (PET), have raised significant environmental health concerns. Because of each plastic’s stability and durability, these plastics exhibit limited natural degradation in the environment. Recently, the environmentally friendly biodegradation of plastics by living microorganisms has attracted more attention, as they can assist in the natural degradation process. In this study, the bacterial strain Bacillus subtilis ATCC6051 was used to degrade LDPE and PET for 60 days. To measure the degradation of low-density (LDPE) and polyethylene terephthalate (PET), the dry weight was taken, and physical characteristics were …

Development And Testing Of A Prototype Erbium-Doped Lithium Tantalate Based Sensor For Infrastructure Crack Detection And Measurement, Alejandro Barrera

Theses and Dissertations

Ensuring the safety and longevity of infrastructure is crucial to safeguarding communities and preserving economic stability. In this study, the development of a novel sensor for detecting and characterizing cracks in infrastructure, particularly suited for deployment on Unmanned Aerial Vehicles (UAVs), is presented. The device utilizes a laser (operating at 980 nm) for excitation of erbium-doped lithium tantalate nanoparticles that emit 1550 nm wavelength, which stimulates a photodiode for data collection. The data was utilized to collect, process, and reconstruct topological information. The synthesized lithium tantalate nanoparticle samples vary in erbium doping percentages of 0.5%, 3%, and 10%. Experimental evaluation …

Microgrid Approach With Data-Driven Monitoring To Enhance The Resilience Of Water Distribution Systems, Binod Ale Magar

Theses

Existing centralized water supply systems are critically threatened by the joint effects of climate and socioeconomic changes, extreme weather events, and physical degradation due to aging, and their changeability. The uncertain and changing drivers pose challenges for water supply systems in providing sustainable water services during disruptions. The energy field dealing related issues has endorsed the microgrid approach with a decentralized energy supply with dispersed local energy sources. The application of energy microgrids has demonstrated their resiliency for sustainable energy supply. For improved resiliency of a water distribution system, this study investigated the application of a microgrid approach and the …

Embedded Sensor Design For Non-Robust Delay Testing, Presh Jayawardana Manannaidelage

Theses

Current delay testing methodologies for integrated circuits face critical limitations, asrobust tests remain unachievable for most paths, forcing reliance on Non-Robust (NR) tests that suffer from unrealistic single-fault assumption, the path under test non being sensitized, and vulnerability to hazard-induced errors. This thesis propose a built-in sen- sor to detect delayed hazards and a sensor to diagnose circuits in the presence of those hazards resulting reliable detection. This thesis intends to propose 2 sensors for non-robust test-based monitoring and test- ing. The first sensor discussed is for IC testing with NR tests. This sensor is capable of detecting any full-swing …

Relationship Between Semi-Aquatic Mammal Occupancy And Particulate Carbon, Nitrogen, And Phosphorus Dynamics In Freshwater Ecosystems, Madison H. Stokoski

Theses

Semi-aquatic mammals such as beavers (Castor canadensis) and muskrats (Ondatra zibethicus) can influence carbon (C), nitrogen (N) and phosphorus (P) dynamics in freshwater systems. While the effect of beavers, in particular, are typically attributed to their dam and lodge building behaviors, these animals do not always build these structures. It’s possible that other, non-damming behaviors (e.g. foraging and burrowing) may influence the availability of nutrients as well. To assess this possibility, we surveyed 54 lentic and lotic waterbodies across Southern Illinois and investigated the possibility that beaver and muskrat occupancy improved our ability to explain variation in nutrient availability across …

Moving Beyond The Php500 Noche Buena Illusion, Marites M. Tiongco, Francine Ysabel D. Gañgan

Angelo King Institute for Economic and Business Studies (AKI)

The recently promoted Php500 Noche Buena package by the Department of Trade and Industry (DTI) has sparked public debate. For some, it is a welcome, “budget-friendly” option. For many, especially low-income households, it feels unrealistic and even dismissive of the sharp increase in food prices in recent years. Retailers and supermarkets have long used similar Php500 holiday baskets as marketing tools.  It is widely used to signal affordability during the holiday season. Yet its persistence masks the cumulative effects of rising prices, stagnant wages, and reduced product quantities. The issue is no longer whether ₱500 can buy a “complete” basket, …

Using Descriptive Phenomenology To Understand Women In Leadership Navigating Work-Life Integration Before And After The Coronavirus Pandemic, Tara Elaine Scroggins Glass

Dissertations

This phenomenological study examined the lived experiences of women leaders as they integrated professional and personal roles before, during, and after the COVID-19 pandemic. Although leadership during crisis has been widely studied, limited research has explored how women leaders across diverse sectors negotiated organizational change while sustaining worklife integration. Guided by the Haddon et al. (2009) model of work-life integration and informed by role conflict, conservation of resources, and intersectionality theories, this study sought to capture the essence of women leaders’ experiences navigating unprecedented disruption. Data were collected through semi-structured virtual interviews with twelve women leaders representing healthcare, education, corporate, …

Sustaining The Workforce: Using Improvement Science To Improve Teacher Self-Efficacy And Well-Being, Stephanie A. Hagerty

Dissertations

Teacher stress remains one of the most pressing challenges facing the education profession, contributing to job dissatisfaction and teacher attrition. This dissertation examines the impact of an intervention designed to improve teacher self-efficacy and well-being. The Leadership Alphabet of Disposition Development Engagement and Reflection (LADDER) framework on teacher self-efficacy and well-being was implemented within a middle school setting. Improvement Science and Adaptive Leadership guided the case study. As defined by Hinnant-Crawford (2020), “Improvement Science is a methodic way of improving; it is distinct from evaluation or impact studies” (p. 23). The goal was to design, implement, and evaluate a strategy …

Using Improvement Science To Build Collective Teacher Efficacy Among Special Education And General Education Co-Teachers In A Title I Elementary School, Pauletha Monique Butts

Dissertations

In this improvement science dissertation, I examined how strengthening co-teaching approaches through targeted training on roles and responsibilities and scheduling time for collaboration builds collective teacher efficacy to improve student achievement for all learners. I conducted a root cause analysis using the Gately and Gately (2001) Co-teaching Rating Scales to better understand the barriers to effective co-teaching in a Title I elementary school in a midsize school district. I implemented two intervention cycles to support general and special education teachers in increasing collective teacher efficacy. The first intervention provided a one-day professional development seminar. The second intervention facilitated planning of …

Investigating Mariculture-Associated Ecosystem Services Across The Northern Gulf Of Alaska, Josianne Haag

Oceanography

The rapid expansion of mariculture in Alaska can drive physical and chemical alterations to the marine environment by introducing non-native organisms or artificially increasing the biomass of a native species. Currently, the main mariculture products grown in Alaska include the Pacific oyster (Crassostrea gigas), the Pacific blue mussel (Mytilus trosuslus), and three macroalgae species: ribbon kelp (Alaria marginata), sugar kelp (Saccharina latissima), and bull kelp (Nereocystis luetkeana). This dissertation examines how these species can impact their surrounding environment to better inform management practices for this growing industry. This research characterized the resource use of C. gigas and M. trossulus seasonally …

Is Universal Health Coverage Really Better? Unintended Consequences Of The 2019 Amendment Of The National Health Insurance Act For Humanitarian Sojourners In South Korea, Minji Ju, Minah Kang, Eunice Y. Park

Department of Public Health Scholarship and Creative Works

Background: South Korea achieved universal health coverage (UHC) through the National Health Insurance (NHI). However, humanitarian sojourners under temporary stay permits were initially excluded. Alongside recommendations from the National Human Rights Commission of Korea (NHRCK), the 2019 Amendment of the NHI Act expanded eligibility of the NHI. While this marked significant progress toward greater universality in health care, it also led to unintended consequences for humanitarian sojourners. Methods: This study employed a two-fold approach aligned with the trajectory of the Amendment. First, we conducted semi-structured in-depth interviews to analyze diverse perspectives on the universality of health coverage, the benefits of …

Cost-Effectiveness Analysis Of Durvalumab In Limited-Stage Small Cell Lung Cancer In The United States, Samuel Kareff

All Publications

Purpose: Small cell lung cancer (SCLC) is an aggressive neuroendocrine malignancy characterized by poor prognosis. The ADRIATIC trial demonstrated significant survival benefits with durvalumab as maintenance therapy for limited-stage SCLC (LS-SCLC). However, the high cost of durvalumab necessitates an evaluation of its cost-effectiveness.

Methods: A partitioned survival model was developed to assess the cost-effectiveness of durvalumab consolidation therapy compared with the standard of care (SOC). The model comprised three mutually exclusive health states: progression-free survival (PFS), progression of disease (POD)/metastasis, and death. Incremental cost-effectiveness ratio (ICER) was calculated as cost per quality-adjusted life year (QALY) gained, with a willingness-to-pay (WTP) …

Safety In Stability: A Cdc-Guided Evaluation Of Hospital Fall Prevention Practices, Matthew C. Dougherty

Electronic Theses and Dissertations 2020 - Present

Hospital falls remain a persistent and preventable cause of patient harm, emphasizing the need for continuous evaluation of fall prevention practices. This project assessed the effectiveness of AdventHealth Orlando’s fall prevention policy using the Centers for Disease Control and Prevention (CDC) Program Evaluation Framework. A mixed-methods design incorporated quantitative analysis of 12 months of fall data and qualitative feedback from frontline staff surveys and discussions. Results demonstrated a decrease in total falls from 549 in the previous year to 528 in the current year, indicating early progress despite the incomplete reporting period. Unit-level analysis showed a mean improvement of 16.9% …

Heartmath: A Stress Reduction Program For Healthcare Providers In An Addiction Treatment Setting, Dihana C. Ruiz

Electronic Theses and Dissertations 2020 - Present

Work-related stress significantly impacts the well-being of healthcare providers, specifically nurses and nurse practitioners, in addiction treatment facilities. This Quality Improvement (QI) project implemented the HeartMath Quick Coherence Technique to reduce stress and enhance resilience among staff, thereby improving the well-being of healthcare providers and the quality of care. The project utilized a pre- and post-intervention design with five participants, two registered nurses, and three nurse practitioners. Participants received training on HeartMath techniques, the EmWave Pro sensor, and the InnerBalance smartphone application. Over a six-week period, participants practiced Quick Coherence meditation for five minutes, twice daily, to achieve heart rate …