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Assessing A Half-Century Of Change In Understory Plant Range And Frequency In The Klamath Mountains Of California, Emily Jean Jackson

Cal Poly Humboldt theses and projects

The effects of climate change have and will continue to impact plant communities, including by potentially shifting species’ ranges towards topographically sheltered, cooler locations or higher elevations. In 2024, I resampled 140 vegetation plots established in 1969 in the Klamath Mountains of Northern California to assess range shifts of 46 understory species over a 55-year period. During this time, the elevational distribution of all species has increased significantly by an average of 26.9 m, but this increase was slower than necessary to track historic temperature niches given regional warming (215-311 m). Despite this overall increase, only four species exhibited significant …

Multi-Omics Analysis Of Immune-Metabolic Adaptation To Direct-Fed Microbial Supplementation In Newly Weaned Beef Steers, Adekunle Odunayo Ajiboye

Graduate Theses, Dissertations, and Problem Reports (ETD)

Immune and metabolic disruption during weaning represents a major challenge to health and productivity in beef cattle. This dissertation tested the hypothesis that supplementation with multi-strain direct-fed microbials (DFMs) modulates immune regulation and metabolic pathways associated with adaptation to weaning stress. To address this, whole-blood transcriptomics and plasma metabolomics were used to evaluate molecular and metabolic responses in newly weaned beef steers during the receiving period. Transcriptomic analysis identified differential expressions of genes associated with immune signaling and inflammatory regulation, indicating modulation of immune-related pathways without changes in growth performance. Metabolomic analysis revealed alterations in circulating metabolites related to amino …

Exploring The Interplay Of Operational Conditions, Microbial Communities, And Water Quality In Drinking Water Ozone-Biofiltration, Kara Yvonne Cunningham

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ensuring reliable access to safe drinking water is a growing global challenge as water utilities face variable source water quality driven by population growth, land‑use change, and climate change impacts. To address these challenges, utilities are implementing advanced treatment technologies designed to improve reliability under variable source water conditions. Ozone-biofiltration has emerged as a treatment approach that can reduce a wide range of natural and anthropogenic contaminants. However, despite its increased use, there is limited insight into the biological processes shaping filter function or how they respond to operational and environmental changes. Advances in molecular microbiology and high-throughput sequencing now …

Hyperglycemia Detection From Sigle - Lead Ecg Using A Hybrid Cnn & Transformer Model, Adam Ayomikun Ogunjembola

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract
Hyperglycemia Detection from Single-Lead ECG using a Hybrid CNN & Transformer Model
Adam Ogunjembola

Diabetes Mellitus is known as high blood glucose. This high blood glucose level happens when the body has a problem with producing or using insulin. Insulin is a very important hormone that the pancreas makes to control how much glucose gets into the bloodstream and cells. Diabetes Mellitus has an effect on the body if it is not treated, such as damaging the blood vessels and nerves which can lead to stroke, kidney failure, heart attack and permanent loss of vision. Since people with diabetes …

Improving Antibiotic Prescribing For Urinary Tract Infections In Urgent Care Centers, Alexis Alastanos

Graduate Theses, Dissertations, and Problem Reports (ETD)

Introduction: Urinary tract infections (UTIs) are one of the most common infections that require antibiotic therapy. Providers working in three urgent care clinics located in Eastern West Virginia diagnosis and treat UTIs based on their clinical judgement. Variability in clinical judgement results in inappropriate antibiotic use which has implications on antibiotic resistance and the financial burden of the patients as well as the entire organization.

Evidence Review: A total of 10 articles were evaluated to support the implementation of antibiotic stewardship initiatives that provide guidance in caring for this population. Interventions include electronic health record enhancements, provider education, and tracking …

Survival, Cause-Specific Mortality, Resource Selection, Movement Rates, And Population Dynamics Of White-Tailed Deer (Odocoileus Virginianus) In West Virginia, Usa, Brett P. Skelly

Graduate Theses, Dissertations, and Problem Reports (ETD)

White-tailed deer (Odocoileus virginianus) are one of the most culturally and economically important big game species in the United States. At the turn of the 20th century white-tailed deer were almost extirpated due to market hunting and unsustainable forestry practices that destroyed habitat. The creation of game laws that eliminated market hunting and created seasons and bag limits for deer hunting along with restocking efforts by sportsmen’s groups and state wildlife agencies aided in deer population recovery. These efforts have led to the abundant deer populations that are currently enjoyed by hunters and wildlife viewers. Deer populations require …

Surrogate-Based Approaches For Evaluating Post-Harvest Food Safety Interventions In Fresh Produce, Md Shafiul Islam Rion

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pathogenic bacteria are still a threat to human beings worldwide as their presence is often unknown even if they are already present in fresh produces. This in turn resulted in several outbreaks and recalls across the United States. This dissertation investigated the survival of pathogenic bacteria and their potential non-pathogenic surrogates after antimicrobial interventions in different modes of applications on the surface of cantaloupes, butternut squash, and fresh cilantro. In the first study, peroxyacetic acid (PAA) was applied in three separate doses on nalidixic acid resistant Salmonella Typhimurium, Listeria monocytogenes, Enterococcus faecium, and Listeria innocua inoculated cantaloupe surfaces …

Evaluating Source Material And Seed Propagation Techniques For Spartina Alterniflora To Enhance Salt Marsh Restoration In Coastal Georgia, Maygan Palacios

College of Graduate Studies: Theses & Dissertations

Salt marshes provide critical ecosystem services, including carbon sequestration, flood attenuation, and habitat for diverse aquatic and terrestrial species. Despite their ecological importance, these habitats are increasingly threatened by anthropogenic activities and rising sea levels. To protect and restore salt marshes and their ecosystem services, restoration efforts using living shorelines (LS) have become more common. Along the Eastern and Gulf coasts of the United States, the native grass Spartina alterniflora is commonly used in LS installations for its key role in salt marsh food webs, resilience to abiotic stress, and ability to stabilize and build sediment. Previous studies have documented …

Low Energy Availability And Dietary Factors In High School Runners, Natalie E. Allik

All Master's Theses

ABSTRACT

LOW ENERGY AVAILABILITY AND DIETARY FACTORS IN HIGH SCHOOL RUNNERS

By

Natalie Elizabeth Allik

June 2026

Context: Low energy availability (LEA) is associated with adverse health and performance outcomes in athletes and may be particularly concerning during adolescence when growth and bone development are ongoing. Although inadequate carbohydrate (CHO) intake has been proposed as a contributor to LEA, limited research has examined this relationship in adolescent endurance athletes. Objective: To examine dietary intake, bone mineral density (BMD), and eating disorder (ED) risk in adolescent distance runners with and without LEA. Methods: Eighteen adolescent distance runners (15.7 ± 1.2 years; …

Ultrasound-Derived Liver Composition And Metabolic Flexibility Under Exercise Stress, Rhodes Van Houten

All Master's Theses

Metabolic Associated Fatty Liver Disease (MAFLD) is characterized by abnormal liver fat accumulation in conjunction with metabolic syndromes. MAFLD affects 33% of individuals worldwide, though little is known about how increased liver fat impacts physiological responses to exercise. This study aimed to analyze the relationship between liver composition and metabolic flexibility during a graded exercise test.  Body composition was analyzed via dual-energy X-ray absorptiometry. Liver ultrasound was evaluated for echogenicity, where elevated mean gray volume (MGV) indicates abnormal liver tissue. Rates of fat (FATox) and carbohydrate (CHOox) oxidation (g/min), respiratory exchange ratio (RER), and blood lactate concentrations ([LA^-], …

Low Energy Availability And Dietary Factors In High School Runners, Natalie E. Allik

All Master's Theses

Context: Low energy availability (LEA) is associated with adverse health and performance outcomes in athletes and may be particularly concerning during adolescence when growth and bone development are ongoing. Although inadequate carbohydrate (CHO) intake has been proposed as a contributor to LEA, limited research has examined this relationship in adolescent endurance athletes. Objective: To examine dietary intake, bone mineral density (BMD), and eating disorder (ED) risk in adolescent distance runners with and without LEA. Methods: Eighteen adolescent distance runners (15.7 ± 1.2 years; 7 males, 11 females) completed baseline assessments including anthropometrics, dual-energy X-ray absorptiometry (DXA), a 24-hour dietary recall, …

Exploring The Impact Of Adverse Childhood Experiences On Preventive Healthcare Utilization In Rural Georgia, Ryan R. Traylor

College of Graduate Studies: Theses & Dissertations

This study examines the relationship between Adverse Childhood Experiences (ACEs) and preventive healthcare use among adults in Georgia, specifically within rural populations facing structural barriers. Using 2023 Georgia Behavioral Risk Factor Surveillance System (BRFSS) data, the research analyzes associations between ACE exposure, rural residence, and preventive care outcomes, including physical exams and flu vaccinations. Guided by an intersectionally adapted version of Andersen’s Behavioral Model of Health Services Use, the study evaluates how predisposing factors, enabling resources, and perceived barriers relate to healthcare engagement. Logistic regression analyses assess the correlation of ACE exposure, cost barriers, provider access, and sociodemographics with preventive …

The Influence Of Localized Water Quality On Eastern Oysters (Crassostrea Virginica) And Their Internal Microbiome Under Changing Environmental Conditions, Jessie Rivera Lafreniere

College of Graduate Studies: Theses & Dissertations

Oysters are found ubiquitously in estuaries along the Georgia coast, where marsh morphology and large daily tidal fluctuations create dynamic and stressful conditions to which oysters may be locally adapted. Based on water quality data from the Sapelo Island National Estuarine Research Reserve, it is evident that changing climatic conditions are rapidly causing shifts in water quality that may be adversely affecting oyster health, especially as ocean acidification alters the carbonate buffering capacity, increasing the amplitude of daily pH variations. Importantly, the rate of change of conditions are not uniform within estuaries, varying on spatial and temporal scales. The symbiotic …

The Effects Of Stress-Related Hormones On Excitatory Synapse Formation, Autumn C. Garvey

Honors Undergraduate Theses

Stress profoundly influences brain function through neuromodulatory hormones that regulate synaptic plasticity, yet how temporal patterns of hormone exposure shape excitatory synapse formation remains poorly understood. This study investigates how exposure to stress hormones, norepinephrine and cortisol, affects excitatory synapse development. While existing research primarily compares concentration models, real-world stress occurs in variable patterns that may produce distinct neural outcomes. To address this gap, differentiated Neuro2A neuronal cells are exposed to norepinephrine or cortisol under a continuous treatment paradigm designed to model chronic stress conditions. Following treatment, immunofluorescence imaging is utilized to quantify excitatory synapse formation through analysis of presynaptic …

Neighborhood Deprivation Associated With Impaired Sit-To-Stand Performance In Middle-Aged And Older Adults: A Cross-Sectional Analysis With Clinical Implications, Kenneth Harrison, Silvia Campos-Vargas, Brandon M. Peoples, Keven G. Santamaria-Guzman, David T. Redden, Michael A. Samaan, Jaimie A. Roper

Kinesiology and Health Promotion Faculty Publications

Background: Socioeconomic factors significantly influence health outcomes in older adults, yet their impact on specific aspects of mobility remains unclear. This study investigates the relationship between area-level socioeconomic disadvantage and mobility health in older adults.

Methods: We conducted a cross-sectional study of 110 community-dwelling older adults recruited and collected using voluntary response sampling at eight health fairs across rural Southeast Alabama in 2022–2024 (60 ± 16 years, 80% female). Area-level socioeconomic status was measured using the Area Deprivation Index (ADI), a validated composite measure of neighborhood disadvantage. Mobility was assessed using the Instrumented Timed Up and Go (iTUG) test and …

The Depuration Of Microplastic Pollution In Aquacultured Indian River Lagoon Oysters, Lee Nguyen

Honors Undergraduate Theses

Plastics are widely used in consumer goods and industrial manufacturing, and their degradation into microplastics (MP, size < 5 mm) has created an emergent environmental pollutant. Plastics readily enter aquatic environments, where they accumulate additional contaminants and bioaccumulate in organisms. While MP contamination in marine ecosystems is well documented, less is known about MP presence in aquacultured shellfish. Depuration, the process of purging contaminants from shellfish, is conducted in sterile seawater without food, which may cause oyster starvation and death. To date, MP depuration has not been examined in the aquacultured eastern oyster (Crassostrea virginica) in published studies. This study had 3 goals: 1) evaluate the effects of algal feed on oyster survival during depuration, 2) determine the effect of algal feed on depuration effectiveness, and 3) investigate the effect of a ten-day depuration on MP concentration in aquacultured C. virginica soft tissue. MP were quantified in oyster tissues, biodeposits, and in industrial algal feed. Tissues were digested using alkaline solutions, manually examined via microscopy, and analyzed using Fourier-Transform Infrared Spectroscopy (FTIR) to investigate MP polymer …

Combining Haptic Feedback With Electromyography To Study Knee Injury In Stationary Cycling, Christopher Kirby

Honors Theses

Patellofemoral Pain Syndrome (PFPS) is the most prevalent overuse injury in cycling, often linked to altered neuromuscular activation patterns of the quadriceps and hamstrings. While sensory feedback has successfully modified cyclists posture, there is a critical lack of evidence-based interventions targeting the underlying muscle activation imbalances associated with chronic knee pain. This study aimed to develop and validate a novel, real-time biofeedback system that utilizes electromyography (EMG) to trigger vibrotactile cues, aiming to shift muscle onset timing earlier in the pedal stroke to mitigate PFPS-related imbalances. A closed-loop system was engineered by integrating a Delsys EMG system with a SageMotion …

A Study Of Adaptive Reuse Of A Decommissioned Golf Course Through A Nature-Based Approach: Woodhaven Golf Course, Fort Wort Texas., Justin B. Watson Mr.

Landscape Architecture Masters & Design Theses

Across the nation, golf courses are shutting down due to a lack of demand. Golf course developments began in the United States in the early 1950s During that era, demand for golf courses and housing was high. As golf’s popularity grew, developers saw golf courses in developments as high value-add amenities (Grooms, 2010). During the late 1990s and early 2000s, developers across the country raced to construct as many golf course communities as they could even as the number of golfers leveled out (Downey,2011).

Decommissioned golf courses across Texas are being underutilized as potential amenities for both the local community …

The Evolution Of California Wildfire Governance Through State Bills, Regulations, And Executive Actions, Cassandra Dawn Blevins

History and Political Science | Senior Theses

California faces an escalating wildfire crisis, driven by climate change, drought, and development in fire-prone areas. Despite decades of scientific research on wildfire behavior and risk reduction, catastrophic fires since 2017 raise a critical question: to what extent have California state laws and policies kept up with the intensifying wildfire crisis? Existing scholarship provides extensive insight into wildfire ecology, land-use planning, fuel management, and community resilience, yet it lacks a comprehensive evaluation of whether California’s legislative, regulatory, and executive actions have adapted in a coordinated and evidence-informed manner. In particular, the literature offers limited analysis of how state laws integrate …

Evaluating The Use Of Precision Technology To Understand Differences Between Ketotic And Non-Ketotic Jersey Cows, Emily Kathryn Palermo

Honors Theses and Capstones

No abstract provided.

Microglial Apoe Across Alzheimer’S Disease-Relevant Pathologies, Georgia Nolt

Theses and Dissertations--Physiology

APOE exists as three common alleles (APOE2, APOE3, APOE4) that encode their corresponding protein isoforms (apoE2, apoE3, apoE4). Despite differing by only one or two single-amino acid substitutions, each APOE allele confers a distinct AD risk profile with APOE4 increasing risk by 28% and APOE2 decreasing risk by 14% compared to the most commonly expressed APOE3 allele. While traditionally considered “neutral,” APOE3 still accounts for ~36% of AD cases while APOE4 contributes ~57%, indicating that the majority of AD cases would not occur in the absence of the APOE3 and APOE4 alleles. Microglia, the resident phagocytic immune cells …

American Elderberry's Next Top Pollinator: Evaluating The Role Of Arthropods In Pollination, Jenny K. Burrow

Graduate Theses/Dissertations

American elderberry (Sambucus nigra subsp. canadensis) is a woody deciduous shrub native to eastern North America. In addition to its long history of use by indigenous peoples, there is renewed interest in cultivating and consuming American elderberry, primarily driven by expanding health supplement markets. Despite recent advances in horticultural development of American elderberry, its pollination ecology remains poorly understood. In this field study, I evaluated the contribution of arthropod visitors to pollination of American elderberry. To do this, I first characterized the identities and abundances of arthropod visitors via timed arthropod collections and floral observations during peak flowering …

Human Plasma Extracellular Vesicles As An Exercise Mimetic To Preserve Skeletal Muscle Plasticity During Disuse, Alexander M. Fliflet, Yanqi Tan, Takeshi M. Barnes, Ane Nishitha Vijayan, Sung Jun Choi

Kinesiology & Sport Management Scholarship

The purpose of this study was to determine the extent to which extracellular vesicles (EVs) circulating in blood after exercise training act as an effective mimetic to maintain skeletal muscle mass during unloading and/or accelerate recovery after disuse. Ten healthy males (27.7 ± 7.1 y) were recruited for a 6-week progressive resistance and endurance training program. EVs were isolated from blood before (EVs) or immediately after training (ExerVs). EVs were intraperitoneally injected into male mice (4×; 3 × 108 particles/injection) during 14 days of hindlimb unloading (HU), then the muscles were collected immediately or 7 days after HU. ExerVs did …

A Transdisciplinary Approach To Advancing Water Security And Public Health: The “Nurse + Engineer” Model For Achieving Sustainability In Wash Systems Using Community-Based Participatory Research, Daniel B. Oerther, Sarah Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Human health is linked to the health of the environment, a concept referred to as planetary health. As environmental challenges become increasingly complex, single-disciplinary approaches are insufficient to achieve sustainable solutions. This article presents a transdisciplinary framework, termed the "Nurse + Engineer" model, as a novel methodology for addressing complex problems at the nexus of environmental engineering and public health. The model integrates the technical design and systems-level thinking of environmental engineering with the community-based, patient-centered care of nursing. This work details the key lessons learned from the retrospective application of this framework to a series of multi-year, community-based participatory …

Environmental Engineers Develop Solutions To Problems Of Planetary Health: The Legacy Of Professor P. Aarne Vesilind, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The principal ethical obligation of the engineering profession, to "hold paramount the health, safety, and welfare of the public," has been challenged for decades. Professor P. Aarne Vesilind identified two primary deficiencies: an anthropocentric bias that values nature only instrumentally and the use of non-mandatory, aspirational language for environmental protection, which resulted in the exclusion of enforceable environmental canons. This paper argues that two recent developments provide a comprehensive response to Vesilind's recommendations for engineering ethics. First, the United States Bureau of Labor Statistics has redefined environmental engineering as "developing solutions to problems of planetary health." Second, Oerther proposed a …

How Effective Is Online Teaching Of Physiology Modules? Perception Of Rwandan Health Sciences Students, Abdullateef Isiaka Alagbonsi, Mojeed Akorede Gbadamosi, Mathieu Nemerimana, Makinde V. Olubiyi, Olufunke Onaadepo, Akaninyene Ubong Ime, Abdul-Rahuf Aderemi Feyitimi, Ruth Wanjiru Mungai, Florent Rutagarama, Simiat Elias

Biomedical Sciences, East Africa

Background: While blended teaching is approved in Rwandan medical education, the perceived effectiveness of online-only delivery for physiology modules remains unclear. This uncertainty limits its continued use. The present study assessed Rwandan health sciences students’ perceptions of the effectiveness of online teaching for physiology modules.

Methods: A total of 528 students from medicine and surgery (n = 300), pharmacy (n = 99), dentistry (n = 89), and clinical psychology (n = 40) programs at the University of Rwanda completed an online questionnaire. Data were analyzed using multivariable logistic regression and non-parametric tests (Mann-Whitney U, Kruskal-Wallis) with corresponding effect …

Development Of A Semi-Mechanistic Pharmacokinetic-Pharmacodynamic Model For Beta-Lactam Antibiotic Combination Against Enterococcus Faecalis Based On Time-Kill Assays To Predict Drug Disposition And Guide Dosing Strategy In A Severe Renal Impairment Population, Ruhma Zia Khan

Selected Full-Text Dissertations 2020-

Bacterial resistance to antibiotics continues to be a global health problem, limiting antibacterial therapy against infective endocarditis caused by Enterococcus faecalis. To overcome increasing resistance, dual beta-lactam therapy has been advocated as an alternative regimen for treatment – the synergistic activity against E. faecalis demonstrated to be effective. Currently, ampicillin plus ceftriaxone is the standard of care, but the practical application of this therapy is limited by ampicillin’s poor stability in solution at room temperature. A synergistic combination of penicillin plus ceftriaxone shows promise due to penicillin’s superior stability at ambient temperature, but ceftriaxone’s potential to cause hepatoxicity further limits …

Umbralisib Antagonizes Multidrug Resistance In Abcb1- Overexpressing Cancer Cells, Letao Bo

Theses and Dissertations

Overexpression of ATP-binding cassette (ABC) transporters, particularly ABCB1, is a major mechanism of multidrug resistance (MDR) and contributes to chemotherapy failure by reducing intracellular drug accumulation. Umbralisib is a dual inhibitor of phosphoinositide 3-kinase delta (PI3Kδ) and casein kinase 1 epsilon (CK1ε) that was developed for the treatment of hematologic malignancies; however, it was later withdrawn due to safety concerns. In the present study, we found that umbralisib has the potential to reverse ABCB1-mediated MDR. The MTT assay demonstrated that umbralisib significantly sensitized ABCB1-overexpressing KB-C2 and SW620/Ad300 cells, as well as ABCB1-transfected HEK293 cells. Mechanistic assays revealed that umbralisib enhanced …

Prevention Of Inflammation-Associated Neurodegeneration: Assessing The Efficacy Of N,N-Dimethylacetamide (Dma) In Lipopolysaccharide (Lps)-Induced Neuroinflammation Using C57bl/6 Mice, Teeshavi Devi Acosta

Theses and Dissertations

Neurological function is closely linked to both longevity and quality of life. While some degree of neurodegeneration occurs naturally with aging, pathological neurodegeneration leads to devastating functional decline. The mechanisms underlying these processes remain incompletely understood; however, neuroinflammation is recognized as a key driver of neuronal dysfunction and death. Emerging evidence indicates that neuroinflammatory cascades can precede and potentiate hallmark features of neurodegenerative diseases, including synaptic loss and cognitive decline observed in Alzheimer’s disease (AD). Activation of the NF-κB signaling pathway contributes to amyloid beta (Aβ) peptide production, further amplifying a cycle of inflammation and neuronal injury. Preclinical work from …

Effectiveness Of Walleye Stocking In Winter Kill Lakes, Tyler Haus

Journal of Earth and Life Science

Winter kill events, marked by extensive fish mortality due to hypoxic conditions under the ice, are a common phenomenon in shallow eutrophic lakes, especially in the northern lakes in the northern United States. These events can drastically alter fish communities and often result in the elimination of top predators. Though these lakes will typically slowly bounce back to what they were in a couple of years. This study evaluates the effectiveness of walleye, Sander vitreus, stocking in lakes after a winter kill. For this study, four known winter kill lakes that are consistently stocked with walleye were studied. Pre- …