Life Sciences Commons^™

Colorimetric Measurement Of Ammonium (Nh4+): A Comparison Of Hanna And Lamotte Meters, Abby Laughlin, Dalton Palmer, Bruce Bugbee

Techniques and Instruments

Both meters were similarly accurate. The LaMotte meter is about 25% lower initial cost than the HANNA meter, but the HANNA meter has other advantages: lower cost and more available test kits, greater range, and ease of use.

South Asian Nutrition Guide For Heart Health: A Practical Guide To Sodium, Saturated Fat, Packaged Foods, Recipes And Meal Planning, Ashwini Wagle

Open Educational Resources

South Asians, including people with ancestry from India, Pakistan, Bangladesh, Sri Lanka, Nepal, Bhutan, and the Maldives, have a higher risk of cardiovascular disease and diabetes than many other populations. They often develop heart disease at younger ages and sometimes at lower body weights. (Jose, 2024; Patel et al., 2021; Volgman et al., 2018).

This increased risk is not caused by a single factor. Evidence points to a combination of inherited, metabolic, lifestyle, and social influences. Common contributors include insulin resistance, abdominal or visceral fat, type 2 diabetes, high triglycerides, low HDL cholesterol, elevated lipoprotein(a), family history, stress, migration-related changes …

Dog Waste Creates A Preference-Performance Mismatch For Urban Dung Beetles, Erin L. Mccullough, Beatrice M. Altopp, Daniel F. Kellogg, Madelyn S. Mcinnis, Luna J. Pagan

Biology

Urban environments expose animals to novel conditions that may favor behavioral flexibility but can create preference-performance mismatches when attractive resources are associated with reduced reproductive success. Dung beetles are often considered dietary generalists, yet little is known about how they respond to altered food availability in human-dominated habitats. We combined field surveys and laboratory experiments using two domestic dung types to examine diet preference, maternal provisioning, and offspring performance in the urban dung beetle Onthophagus orpheus. Beetles strongly preferred dog dung over cow dung, and offspring reared on dog dung developed faster and emerged as larger adults. Despite these apparent …

Microbiota Characterization Of Zostera Marina Seeds At Early Stage Development, Gina Chaput, Torrie Hanley, Jonathan A. Eisen, E. Maggie Sogin, A. Randall Hughes, Cynthia G. Hays

Biology Faculty Publications

Understanding seagrass seed microbiomes is crucial for developing microbial-mediated methods to improve germination in restoration efforts. Here, we used 16S rRNA gene and ITS2 amplicon sequencing to characterize the bacterial and fungal communities of seeds from the model seagrass, Zostera marina.

Investigating The Potential Neurotoxic Effects Of Cell-Free Factors By Batrachochytrium Dendrobatidis On Locomotion In Xenopus Laevis, Anna Lennon, Laura K. Reinert, Louise A. Rollins-Smith, Will Best, Chase T. Kinsey Phd

Funded Scholarship

Chytridiomycosis is a contributor to amphibian population declines. Diseased amphibians show symptoms of lethargy and loss of righting reflexes, likely due to ion imbalance across the skin. However, it is possible developing zoosporangia release toxins that affect neuromuscular activity. Using Xenopus laevis as a model, we hypothesized that locomotor performance would be affected by injection of Bd supernatant factors. X. laevis were injected and then filmed performing a swimming escape response with high-speed cameras at 4 hours, 24 hours, and 1- week post-injection. Average maximum swimming velocity and escape latency were digitized using high speed video. Despite no difference in …

Comparison Of Enrichment Interaction Duration Between Male And Female Panthera Leo Leo, Maegen G. Meldrum

Undergraduate Honors Thesis Projects

African lion (Panthera leo leo) populations have declined significantly over the past century within their natural habitats, increasing the importance of effective management strategies for individuals in human care. Environment enrichment is a critical tool for promoting species typical behavior in human care; however, enrichment practices are often generalized and may not account for sex-specific differences. This study examined how sex, enrichment types, behaviors, and time of day influenced enrichment interaction duration in a small pride of African lions (n = 4) housed at the Columbus Zoo and Aquarium. Two enrichment types were evaluated: cognitive/occupational (CO, a manipulable barrel) …

Behavioral And Electrophysiological Responses Of Fall Armyworm Larval Parasitoid Coccygidium Luteum To Maize And Companion Plant Volatiles, Emmanuel Peter, Sevgan Subramanian, Abdullahi Yusuf, Samira A. Mohamed, Baldwyn Torto, Emily A. Martin, Amanuel Tamiru

All Peer-Reviewed Publications

Companion cropping and biological control are among the best agronomic practices recommended for ecologically sustainable management of the invasive fall armyworm (FAW), Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae). Companion plants may suppress the FAW population by repelling the pest, disrupting host-plant location and recruiting biocontrol agents such as parasitoids. These interactions are primarily mediated by plant-derived volatile organic compounds (VOCs). Understanding parasitoids’ responses to VOCs emitted by companion plants enables selection of suitable cultivars to enhance biological control and design appropriate intercropping systems for effective FAW management. This study investigated behavioral and electrophysiological responses of a key FAW larval parasitoid, …

Taxonomy, Distribution And Ecology, Biology, Nutritional Composition, And Conservation Status Of Critically Endangered Lake Chala Tilapia Oreochromis Hunteri (Günther, 1889): Implications For Aquaculture Development, Jonathan Munguti, Mavindu Muthoka, Domitila Kyule, Esther Magondu, Jacob O. Iteba, Kevin Obiero, Paul Orina, Menaga Meenakshisundaram, Tanga M. Chrysantus

All Peer-Reviewed Publications

Oreochromis hunteri Günther, 1889, commonly known as Lake Chala tilapia, is an endemic cichlid restricted to the small crater lake, Lake Chala, on the border of Kenya and Tanzania. This review synthesizes existing knowledge on the taxonomy, and phylogenetic placement, distribution and ecology, and biology including nutritional composition, and conservation status of O. hunteri and identifies knowledge gaps to assess its potential for aquaculture development. The knowledge gaps include its reproductive biology, population structure, and adaptive capacity to environmental and climatic variability. As the type species of the genus Oreochromis, O. hunteri is a unique, genetically isolated lineage within a …

Brief Therapy Dog Interactions May Increase Self-Efficacy And Lower Perceived Stress And Cortisol In High School Students: A Preliminary Study, Dawn Melzer, Deirdre Yeater, Madison Derubis, Christiana Rose Kohlroser, Barbara J. Pierce

Psychology Faculty Publications

The present study examined changes in high schoolers’ perceived stress, general self-efficacy and cortisol levels after a brief interaction with a certified therapy dog. High school students completed self-report measures of perceived stress and general self-efficacy and provided salivary cortisol samples both before and after a 10-min interaction with a certified therapy dog. Following the interaction, students reported reductions in perceived stress scores, exhibited lower salivary cortisol concentrations and demonstrated increases in self-efficacy scores compared to before the interaction. Although higher self-efficacy scores were observed, general self-efficacy is generally regarded as a stable construct; therefore, these findings may reflect a …

Organized Sports-Based Interventions And Motor Outcomes In Children Diagnosed With Autism Spectrum Disorder: A Systematic Review, Kailash Ram, Maeren Hill, Caitlyn Stewart, Kaitlin P. Hardy Md, Sonia Khurana

Rehabilitation Sciences Faculty Publications

Aim

To evaluate the effectiveness of organized sports-based interventions on motor outcomes in children with autism spectrum disorder (ASD).

Method

Four databases were searched from inception to November 2025 for randomized controlled trials (RCTs) and non-randomized controlled trials (NRCTs) reporting motor outcomes of organized sports-based interventions in children with ASD. Risk of bias was evaluated using ROB-2 (Cochrane Risk of Bias Tool, Version Two) for RCTs and ROBINS-I (Risk Of Bias In Non-randomized Studies - of Interventions) for NRCTs.

Results

Eleven studies (six RCTs, five NRCTs) were included and categorized as martial arts (n = 5), aquatic training (n = …

Factors Influencing Tree Vigor And Structural Failure Along Powerline Corridors In Northern California: A Multi-Species Analysis, David Justin Dorval

Cal Poly Humboldt theses and projects

Tree failures (e.g., stem breakage, uprooting, or branch drop) can pose significant risks to public safety, particularly along powerline corridors for the risk of power outages and wildfire ignitions. In California, tree-related powerline failures have led to severe ecological and human costs in recent years. Despite extensive research on tree failure in urban environments and post-disturbance contexts, comparatively little empirical work has examined where powerlines intersect largely unmanaged stands. This study evaluates tree failure trends across multiple forest types in Northern California by examining how tree-level characteristics influence recent growth and failure occurrence in regionally dominant tree species. Specifically, the …

Baker Cypress (Hesperocyparis Bakeri) In A Changing Fire Landscape: Characterizing Fire Refugia And Guiding Post-Fire Reforestation, Olivia Lorraine Moskowitz

Cal Poly Humboldt theses and projects

Increasing wildfire frequency threatens serotinous, fire-obligate species that depend on sufficient fire-free intervals to develop seed banks for reproduction. These species require fire intense enough to trigger seed release and create favorable substrate and light levels for regeneration, yet consecutive fires that reburn populations before they reach maturity can cause local population contraction or extirpation. Understanding the environmental drivers of natural regeneration and mature tree survival, as well as when and how active reforestation should supplement natural recovery, is critical for managing fire-adapted species under altered fire regimes.

This thesis uses Baker cypress (Hesperocyparis bakeri [Jeps.] Bartel), a rare …

Do California Rangeland Healthy Soil Practices Offer Co-Benefits For Grassland Birds?, Ximena O. Gil

Cal Poly Humboldt theses and projects

Rangelands are important landscapes in California that support a robust cattle industry and serve as vital grassland habitat for birds. Climate change is projected to impact rangelands, leading to economic and ecological deterioration. In California, the Healthy Soils Program (HSP) incentivizes climate-smart solutions to increase working land resiliency. While the HSP targets soil and range health for livestock, it may also benefit birds. We surveyed rangeland operators to examine whether the implementation and duration of specific range management practices, such as range seeding, prescribed grazing, and silvopasture, are associated with bird community responses, using avian point count data from Point …

Forest Management Options For The Wildland Urban Interface: Comparative Analysis Of Stand Development, Economics, And Forest Carbon Over 100 Years In Sierra Nevada Ponderosa Pine, Kassandra A. Mcdaniel

Cal Poly Humboldt theses and projects

This thesis presents a simulation study of various forest stand treatments and their long-term effects on ponderosa pine-dominated forests in the Sierra Nevada Mountain Range of the western USA. The goal was to create recommendations for forest management in the wildland urban interface (WUI) of the Tahoe National Forest and other locations with similar conditions. This study simulates current United States Forest Service (USFS) - Truckee Ranger District silvicultural treatment alternatives repeated over a 100-year period using the USFS Forest Vegetation Simulator (FVS). Proposed treatment alternatives include restoration, resilience, transition, conservation, and no management. Treatments are to be compared in …

Regeneration And Fuel Loading With Varying Overstory Retention In Redwood Stands 10 Years After Transformation To Multiaged Management, Jud Fisher

Cal Poly Humboldt theses and projects

Forest managers using retention forestry in western forests need information on regeneration dynamics and fuel development to design stands that are both productive and fire resilient. This study analyzes 10-year remeasurement data from the Redwood Multiaged Experiment in Jackson Demonstration State Forest, California, comparing regeneration and fuel responses across group selection (GS), aggregated (HA), and dispersed (LD, HD) retention treatments. Target relative density (RD) of the residual stand was zero in GS, 13% in LD, and 21% in HA and HD. Measurements included sprout growth and size of redwood and tanoak, seedling and sprout density, and surface fuel loading.

Redwood …

Succession And Alpine Plant Habitat Of A Recently Deglaciated Foreland In The Trinity Alps, California, Sebastian Evans

Cal Poly Humboldt theses and projects

The recent extinction of the Salmon Glacier in the Trinity Alps, California, provides a rare opportunity to examine post-glacial succession in a region of high endemism experiencing climatic stress. Using a chronosequence spanning ~150 years since deglaciation, I investigated (1) vegetation successional trajectories in the foreland, (2) whether the foreland functions as a climate refugium for alpine specialists, and (3) whether facilitative interactions between the dominant vascular plant (DVP) and bryophytes occur and persist through succession. I surveyed 100 plots across 11 transects within the foreland and 40 randomized plots in adjacent ecosystems. Successional patterns and refugial potential were analyzed …

From Theory To Ecosystems: Exploring Biodiversity And Ecosystem-Function In Pitcher Plant (Darlingtonia Californica) Microbial Communities, Gavin Sutter

Cal Poly Humboldt theses and projects

The relationship between biodiversity and ecosystem-function (BEF) has been a central focus of ecological research for the last three decades, yet the role of space in shaping BEF relationships remains relatively unknown. Research has shown that community diversity and composition can strongly influence productivity, nutrient cycling, and decomposition, but much of this work treats communities as spatially isolated, leaving open how dispersal and other spatial processes shape BEF at broader scales. To begin addressing this gap, I used microbial communities inhabiting Darlingtonia californica pitcher plant leaves to evaluate how spatial organization and successional change shape biodiversity and ecosystem-functioning. I quantified …

Effects Of Coaching Interventions On Burnout And Mental Health Outcomes Among Collegiate Athletes: A Meta-Analysis, Natalie Mitchell

Cal Poly Humboldt theses and projects

This meta-analysis examined the effects of coaching interventions on burnout and mental health outcomes among collegiate athletes. Following PRISMA guidelines, literature published from 1980 onward was searched across SPORTDiscus, PsycINFO, PsycARTICLES, PubMed/MEDLINE, Web of Science, and ProQuest Theses & Dissertations. Studies were included if they assessed burnout, psychological well-being, or related mental health outcomes in collegiate athletes and investigated a coaching intervention. Twelve interventional studies met the inclusion criteria. Across studies, coaching interventions varied in structure, duration, sport context, and cultural setting, with most emphasizing intrapersonal strategies and emotional or mental health outcomes. Meta-analytic results indicated small, non-significant effects favoring …

Predicting Oil Contamination In Water Using Machine Learning On Microbial Compositions, Tong Gao, Isaac Bigcraft, Stephen Techtmann, Issei Nakamura

Michigan Tech Publications

We present a compact and generative machine-learning framework that predicts oil contamination based on microbial community compositions from experimental samples. Our method combines dimensionality reduction with data augmentation and generative modeling to address high-dimensional, non-linear, and sparse microbial data. To reduce the 503-dimensional bacterial composition dataset, we compared three dimensionality reduction techniques: feature importance from random forest, principal component analysis (PCA), and t-distributed stochastic neighbor embedding (t-SNE). Feature importance outperformed PCA and t-SNE, improving predictive performance and identifying microbial species most strongly correlated with oil contamination. To mitigate data scarcity, we augmented the training data using an augmented data neural …

Tree Composition And Carbon Turnover Dynamics Across 22 Years In A Costa Rican Premontane Moist Forest Fragment, Milena Cambronero, Fabián Araya-Yannarella, Lauren Holmes, Jill Cass

Student Publications [Scholarly]

Aim of study: Tropical forests are increasingly threatened by deforestation and fragmentation. In Costa Rica, extensive land-use change has left forest fragments whose long-term ecological dynamics remain poorly understood. This study assessed changes in tree diversity, composition, structure, and aboveground carbon stocks during a 22-year period (2000-2022) in a premontane moist forest fragment in Costa Rica. Area of study: Municipal Forest of Atenas (26.4-ha), Alajuela, Costa Rica. Material and methods: Tree inventories were conducted in 32 plots (10 m radius) in 2000 and 33 plots in 2022. We analysed diversity and composition using Bray-Curtis dissimilarity, Hill numbers, and Importance Value …

Bio-Orthogonal Chemistry-Based Strategy To Turn-On And Turn-Off Crispr-Cas9 Gene Editing In Solution And In Live Cells, Bhoomika Pandit

Electronic Theses & Dissertations (2024 - present)

The CRISPR–Cas9 system is a widely popular tool for genome engineering. There is a strong interest in developing tools for temporal control of CRISPR-Cas9 activity to address some of the challenges and to broaden the scope of potential applications. In this thesis I describe two biorthogonal based approaches to either Turn-ON and Turn-OFF CRISPR-Cas9 gene editing.

In first project work I describe a bio-orthogonal chemistry-based approach to Turn-ON Cas9 nuclease activity with temporal precision. We report a TCO-acylimidazole reagent that acylates 2′-OH groups of RNA. Poly-acylation (“cloaking”) of RNA was optimized in vitro using a model 18-nt oligonucleotide, as well …

Stem Cell-Derived Developmental Models For Translational Evaluation Of Disease And Therapy, Maria B. Paredes-Espinosa

Electronic Theses & Dissertations (2024 - present)

Human development as well as congenital and adult diseases emerge from coordinated interactions among multiple cell types, regulatory programs, and tissue compartments that remain largely unresolved. Conventional simple lineage-restricted in vitro systems poorly capture this complexity. My dissertation uses human stem cell-derived developmental models to study human cardiac morphogenesis and heart diseases and application of a networked neuron platform to explore senescence-associated neurodegeneration impact on Alzheimer’s neurons.

Elongating multi-lineage organized cardiac (EMLOC) gastruloids are a synthetic embryology model that co-generates contractile cardiomyocyte populations alongside mesenchymal, endothelial, epicardial-like, neural crest-associated, and neuronal cells within a shared in vitro developmental environment. Single-cell …

A Multi-Omic Approach For Understanding The Individual Roles Of Atf4 And Atf3 Upon Induction Of Different Branches Of The Integrated Stress Response, Elianna T. Cruz González

Electronic Theses & Dissertations (2024 - present)

The integrated stress response (ISR) is a critical cellular pathway that coordinates adaptation to various stressors, including endoplasmic reticulum (ER) stress, amino acid (AA) starvation, heme deficiency, and viral infection. Central to this pathway are the transcription factors ATF4 and its downstream target ATF3, which regulate gene expression programs that influence cell survival, metabolism, and immune responses. While previous studies have identified ATF3 as an antiviral factor during Zika virus (ZIKV) infection, the broader relationship between ATF3 and ATF4 across multiple branches of the ISR remains incompletely understood.

In this study, I employed multi-omic approaches to characterize the roles of …

The Chemistry Of Red Lipstick: The Impact Red Lipstick Has On Society, Lilliana Weldeslassie

Electronic Theses & Dissertations (2024 - present)

Cosmetic chemistry is deeply embedded in everyday life, shaping the products people use from morning to night. Among these, red lipstick stands out as a formulation that blends complex chemistry with a cultural meaning. This thesis examines the scientific foundations of red lipstick through its chemical composition, pigment structure, toxicological history, analytical methods, and evolving sustainability practices. Historically, red lipsticks relied on high-risk ingredients such as lead, mercury, and other toxic metals, reflecting an era before chemical safety and regulatory oversight were incorporated.²¹ Modern formulations have established safer synthetic dyes, natural waxes, plant-based oils, and stabilizers created to optimize …

Bioinformatic Identification And Analysis Of Shared Splicing Errors In Myotonic Dystrophy Type (Dm1) And Fuchs' Endothelial Corneal Dystrophy (Fecd), Carter I. Wilkins

Electronic Theses & Dissertations (2024 - present)

Myotonic dystrophy type 1 (DM1) is an autosomal dominant form of muscular dystrophy, and it is the most common form of adult-onset muscular dystrophy. The disease is the result of CTG trinucleotide repeats (TNR) in the 3’UTR of the dystrophia myotonica protein kinase (DMPK) gene. This produces toxic RNA hairpin structures by CUG repeat expansions that sequester proteins–most relevantly muscleblind-like 1 (MBNL)–that regulate alternative RNA splicing. The missplicing of a wide variety of genes results in the symptoms such as myotonia (rigidity of the muscles), atrophy, and cardiac failure.

Fuchs’ Endothelial Corneal Dystrophy (FECD) is characterized by progressive loss and …

Multifunctional And Adaptive: Tracking How Fibroblasts Respond To Tissue Injury And Facilitate Tissue Remodeling, Joey R. Tavarez

Electronic Theses & Dissertations (2024 - present)

Fibrosis is characterized by an accumulation of proteins in the extracellular matrix (ECM) that results in altered tissue architecture and reduced organ function. In the salivary glands, fibrosis leads to loss of saliva, dysbiosis of the oral microbiome, an increase in oral infections, difficulty in digestion of food and an overall reduction in the quality of life. Understanding the progression of fibrosis and how it affects human health is a crucial step for designing effective therapeutics. Understanding fibroblast function is integral to advancing the field due to the many roles they play in maintaining the ECM. To perform preliminary analysis, …

Combating Antibiotic Resistance With Plasmid-Dependent Phages, Rhiannon T. Mariano

Electronic Theses & Dissertations (2024 - present)

The alarming rise of carbapenem-resistant bacteria poses an urgent global health threat, driven in large part by the horizontal spread of carbapenemase-encoding plasmids (Ma et al., 2023). These plasmids are often highly mobile and transmissible, enabling rapid dissemination of resistance genes across diverse bacterial populations. Their mobility is largely mediated by conjugation, a process dependent on the formation of pili, which serve as physical bridges for plasmid transfer between cells (Murray et al. 2022; San Millan and MacLean 2017; Virolle et al. 2020). Beyond their role in gene exchange, these pili also act as entry points for a unique class …

Development And Applications Of Fluorescence Microscopy Protocol To Investigate Borrelia Burgdorferi Immune Interactions In The Skin, Rebecca V. Landry

Electronic Theses & Dissertations (2024 - present)

The skin is an immunological organ that acts as the hosts’ first line of defense against infectious agents. Infectious disease vectors like ticks breach this barrier by feeding on hosts, transmitting pathogens like Borrelia burgdorferi in the process. Uncleared infection with B. burgdorferi causes Lyme disease, the most prevalent vector-borne disease in the United States. Previous research has explained many elements of Lyme disease pathogenesis and immunity including the dissemination of the spirochete, innate immune cells performing phagocytosis, the production of antibodies by the humoral response, and the impact of prophylactic treatment with monoclonal antibodies. A remaining gap in the …

The Effects Of Vitamin K On Neuronal Ferroptosis, Chelsey P. Eighmey

Electronic Theses & Dissertations (2024 - present)

Dementia is a crippling illness affecting millions worldwide causing significant public health burdens with long-term care. The lack of treatment options results in many years of suffering for affected individuals and their loved ones who often become primary caretakers. Decades of study have focused on treating dementia with little-to-no success, so an emphasis is needed on attempting to prevent disease progression altogether. This research explored vitamin K as a potential strategy for prevention of dementia onset or progression through the mechanism of suppressing ferroptosis. Ferroptosis is a type of cell death suggested to contribute to the hallmark traits of Alzheimer’s …

End-To-End Modeling For The Ross Sea Region Marine Protected Area: A Review Of Available Tools For Conservation Objectives, James R. Lovvorn, Cara Nissen, Alexis A. Bahl, Erik Behrens, Cassandra M. Brooks, Katy Christensen, Michael S. Dinniman, Lilian A. Dove, Alice K. Duvivier, Eileen E. Hofmann, Hayley Kwasniewski, Young Shin Kwon, Sharon E. Stammerjohn, Lei Xing

CCPO Publications

The challenge of protecting marine ecosystems, including biodiversity and manifold interactions in changing environments, has encouraged development of end-to-end models linking physical drivers through entire food webs to upper-level predators. Ideally such models should have temporal and spatial resolution adequate to capture important small-scale processes, while including scales large enough to encompass local food webs and movements of wide-ranging consumers. The need for component submodels to be manipulated and upgraded independently by scientists from different disciplines, and used selectively depending on questions addressed, favors modular structure allowing linkage of different submodels with varying strengths and weaknesses. As an example, this …