Digital Commons Network^™

Effects Of Temperature On The Life-History Traits Of Myzus Persicae And Its Efficiency In Transmitting Potato Virus Y (Pvy) In Potato Crops, Bonoukpoè M. Sokame, Henri E. Tonnang, Heidy Gamarra, Pablo Carhuapoma, Jan Kreuze, Leah R. Johnson, Ali Arab, Peter A. Armbruster, Oswaldo C. Villena

All Peer-Reviewed Publications

Aphids are highly sensitive to temperature changes and play a crucial role in transmitting plant viruses, accounting for the transmission of more than 50% of viruses that cause disease in crops. Among them, Myzus persicae is a major global pest, affecting over 400 plant species and transmitting more than 100 plant viruses, including potato virus Y (PVY), which poses a severe threat to potato crops. This study examines how temperature influences the life-history traits of M. persicae and its efficiency in transmitting PVY. Our research revealed that temperature significantly affects developmental duration, survival, and fecundity of M. persicae. The aphids …

Detecting Habitat Use Of Three Endemic Freshwater Fish Of Far Southwestern Australia, Paige Rhiannon Wilson

Theses: Doctorates and Masters

The wetland ecosystems of far southwestern Australia face multiple threats including land clearing, historical cattle grazing, changed hydrology, extensive groundwater extraction, and changed fire regimes. Each is exacerbated by a drying climate, and together they provide a significant challenge to the on-going survival of the freshwater fish in this region particularly fish that are endemic, range restricted, and therefore, more likely to be more vulnerable. This study focuses on three such species: Galaxiella munda, Galaxiella nigrostriata and Lepidogalaxias salamandroides, the latter two of which are known to aestivate.

In order to make conservation decisions regarding management of wetlands for …

Geographic Variation In Proteomic Responses To Ocean Acidification In A Cold-Water Coral (Balanophyllia Elegans), Keana A. Richmond

Cal Poly Humboldt theses and projects

In the face of a rapidly changing climate, assessing organismal responses to future stressors in the context of current, natural exposure to stress could provide key insights to understanding marine ecosystem resilience. I used Balanophyllia elegans, a cold-water, solitary, azooxanthellate coral as a model to better understand how varying oceanographic conditions across its geographic range have shaped its ability to tolerate and potentially adapt to current and future ocean acidification conditions. I collected B. elegans individuals from four sites across 2,500km of their range and subjected them to two pH treatments to investigate site-specific protein expression in response to …

Coho Salmon (Oncorhynchus Kisutch) Response To Habitat Restoration Through Space And Time: Monitoring Growth, Survival, And Movement In A Restored Habitat Network, Carter Perez Adamson

Cal Poly Humboldt theses and projects

Despite the decline of coho salmon (Oncorhynchus kisutch), Prairie Creek, a tributary of Redwood Creek in northern California, remains a coho salmon stronghold. The restoration of juvenile coho rearing habitat was identified as a recovery objective in this watershed by the National Marine Fisheries Service. Among the restoration projects addressing this objective are an ongoing project on Prairie Creek and its tributary Skunk Cabbage Creek, and a prior effort on Strawberry Creek (a tributary of Redwood Creek’s estuary). Standard monitoring methods for assessing project success have limitations and may be improved by measuring salmon use of restored habitats …

Ectomycorrhizal Fungi Associated With Pinus Species Of California's Northwestern Coast, Monika Audrey Richardson

Cal Poly Humboldt theses and projects

Ectomycorrhizal (ECM) fungi are vital for increasing host plant uptake of nutrients and stress tolerance within ECM forest ecosystems. The species assemblage of ECM fungi can vary locally in response to numerous biotic and abiotic environmental factors. In California’s northwestern coast the occurrence of three Pinus species, along with a disjunction between populations of Pinus muricata in Mendocino and Humboldt Counties, offer a unique opportunity to investigate the spatial and host effects on pine-associated ECM fungi. Ectomycorrhizal fungal community structure was quantified from host tree roots and sequenced sporocarps occurring at the same sites to create a project specific ITS …

Evidence Of Personality And Movement Syndromes In A Mobile Predator: How Individual Hunting Strategy Shapes Ecosystem Service Potential By Barn Owls (Tyto Furcata) In An Agroecosystem, Lauren M. Jackson

Cal Poly Humboldt theses and projects

Animal-mediated ecosystem services are delivered through the behavior of individuals, yet most studies evaluate service-providing species at the population level. We tested whether individual variation in plumage, behavior, and movement predicted hunting behavior and vineyard habitat use by adult male American barn owls (Tyto furcata) nesting in winegrape vineyards in Lodi, California, USA. We fitted GPS-accelerometer tags to 42 breeding males, quantified breast-plumage traits, measured neophobia using repeated novel object tests, and derived nightly movement metrics from GPS tracks and hidden Markov model-classified hunting locations. Several behavioral traits were repeatable, but movement traits showed the clearest repeatable individual …

A Comprehensive Overview Of Neurophysiological Correlates Of Cognitive Impairment In Amyotrophic Lateral Sclerosis, Seyyed Bahram Borgheai, Brie E. Achorn, Alyssa H. Zisk, Sarah M. Hosni, Karl E. G. Richter, Frank S. Menniti, Yalda Shahriari

Computer Science Faculty Publications

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that leads to the gradual loss of motor control, typically resulting in paralysis and death within 3 to 5 years of diagnosis. ALS shares neuropathological and genetic associations with fronto-temporal dementia (FTD), a neurodegenerative condition primarily impacting cognitive functions. These two conditions are increasingly viewed as manifestations of a single molecular disease process that affects distinct brain systems, impacting motor neuronal pathways in ALS and fronto-cortical functions in FTD. However, this simple dichotomy belies the complexity of these conditions. In particular, patients with primary motor ALS can also experience significant cognitive …

Explainable Convolutional Neural Network Model Provides An Alternative Genome-Wide Association Perspective On Mutations In Sars-Cov-2, Parisa C. Hatami, Richard Annan, Luis Miranda, Jane L. Gorman, Mengjun Xie, Letu Qingge, Hong Qin

Computer Science Faculty Publications

Identifying informative genomic features in SARS-CoV-2 can help clarify patterns of viral evolution. In this study, we developed an explainable convolutional neural network (CNN) model to classify SARS-CoV-2 genomic sequences into the WHO-designated Variants of Concern (VOCs), Alpha, Beta, Gamma, Delta, and Omicron. Using a balanced dataset of genomes, the classification CNN achieved 99.96% accuracy on the held-out test set. To interpret the model’s predictions, we applied SHapley Additive exPlanations (SHAP) to estimate the contribution of each nucleotide position to VOC-label prediction and compared aggregated attributions with a chi-square GWAS baseline applied to the same categorical labels. SHAP prioritized several …

Immune Suppression And Epigenetic Reprogramming In Epithelial-Mesenchymal Transition, Hanxu Lu

Dartmouth College Ph.D Dissertations

Epithelial-mesenchymal transition (EMT) is increasingly recognized as a dynamic spectrum of cellular programthat contributes to tumor progression, metastasis, and therapeutic resistance. Rather than existing as discrete epithelial or mesenchymal phenotypes, tumor cells undergo intermediate EMT states in which epithelial and mesenchymal features are partially and variably expressed. In this thesis, I studied EMT state heterogeneity through two complementary and integrated dimensions: tumor-immune interactions and the dynamic remodeling of epigenetic programs across the EMT spectrum. Using a clonal EMT model derived from the murine triple-negative 4T1 mammary carcinoma cell line, including epithelial, intermediate, and mesenchymal states that are stably maintained in …

Dietary Ecology Of Waterfowl Nest Predators In The Prairie Pothole Region: Evaluating Resource Use From Species To Individual Using Stable Isotope Analysis, Grace Barthelmess

EWU Masters Thesis Collection

Nest predation is a primary factor influencing waterfowl productivity in the Prairie Pothole Region (PPR) of North America. Although this system is intensely managed and studied, research has largely focused on how predators affect waterfowl populations, with comparatively little attention to how predators actually rely on waterfowl as a resource. Understanding predator feeding ecology is therefore critical for informing effective management strategies and interpreting the complexity of predator-prey interactions on this landscape. My objective overall was to elucidate the feeding ecology of nine focal predator species commonly associated with waterfowl nest predation in the Aspen Parkland Ecoregion of the PPR: …

Relationships Between Benthic Macroinvertebrate Communities And Environmental Conditions In Headwater Tributaries Of The Pend Oreille Lake Watershed, Idaho, Devlin Mee

EWU Masters Thesis Collection

Benthic macroinvertebrates are widely used indicators of stream condition, and their communities respond to thermal and land-use conditions in headwater streams. This study characterized macroinvertebrate biomass, community composition, and diversity across forested headwater tributaries of the Pend Oreille lake watershed in northern Idaho, and examined their relationships with summer temperature, land development, and road proximity. Samples from thirteen streams collected in 2024 were identified to genus, measured, and converted to estimated biomass using published length–mass regressions; ten streams had recovered temperature loggers. Because environmental variables were characterized once per stream, all analyses were conducted at the stream level.

Estimated total …

Gcn5l1-Mediated Lysine Acetylation Regulates Mitochondrial Dysfunction In The Aged Heart, Jackson Edmond Stewart

Graduate Theses, Dissertations, and Problem Reports (ETD)

For over a century, cardiovascular disease (CVD) has been and remains the leading cause of death globally. CVD risk and severity increase significantly with advanced age, and mitochondrial dysfunction has been implicated in the pathogenesis of aging. Furthermore, mitochondrial health is crucial for cardiac function, as one-third of total cardiomyocyte volume is occupied by mitochondria in order to meet the high energy demand of contractile and relaxational function. It is thus crucial that we understand the pathological mechanisms driving mitochondrial dysfunction in aging and how this contributes to age-associated cardiovascular disease. The current manuscript aims to fill this knowledge gap …

Intelligent Torque Control Of Switched Reluctance Motors Based On Ditc And Wavelet Neural Network, Ameer L. Saleh, László Számel

Mansoura Engineering Journal

Switched Reluctance Motors (SRMs) have been considered a high-performance and environmentally friendly solution for Electric Vehicle (EV) applications owing to their simpler construction, robust design, and high efficiency. However, it suffers from high torque ripple and acoustic noise due to its highly nonlinear magnetic characteristics and double-salient structure.  This paper introduces a nonlinear torque control based on the Direct Instantaneous Torque Control (DITC) scheme and a Wavelet Neural Network (WNN)  to achieve better dynamic response and mitigate torque ripple.  The proposed WNN is employed as a nonlinear torque controller, inserted between the torque error and the hysteresis torque controller within …

Markov Chain Wave Generative Adversarial Network For Bee Bioacoustic Signal Synthesis, Kumudu Samarappuli, Iman Ardekani, Mahsa Mohaghegh, Abdolhossein Sarrafzadeh

Electrical & Computer Engineering Faculty Publications

This paper presents a framework for synthesizing bee bioacoustic signals associated with hive events. While existing approaches like WaveGAN have shown promise in audio generation, they often fail to preserve the subtle temporal and spectral features of bioacoustic signals critical for event-specific classification. The proposed method, MCWaveGAN, extends WaveGAN with a Markov Chain refinement stage, producing synthetic signals that more closely match the distribution of real bioacoustic data. Experimental results show that this method captures signal characteristics more effectively than WaveGAN alone. Furthermore, when integrated into a classifier, synthesized signals improved hive status prediction accuracy. These results highlight the potential …

Effects Of Volatile Organic Compounds Produced By Temperature-Adapted Microbes On Duckweed Growth, Phaedra Yael Stemp

Honors Theses and Capstones

As host-associated microbes adapt to their abiotic environment, these adaptations can affect their host species as well. Previous research showed that varying temperatures and volatile organic compound (VOC) production can affect microbial benefits to hosts. This experiment analyzed how 27 microbes pre-adapted to different temperature conditions affected growth of their host, common duckweed plants, comparing effects of direct contact with microbes, effects of microbe VOCs alone, or both. Each microbe was pre-adapted to one of three temperature regimes: “Northern” at 28 °C, “Southern” at 33 °C, and “Extreme” at 36 °C. We then grew duckweeds in I-plates with each microbe …

Exploring The Effects Of Voluntary Wheel Running On Inhibitory Control, Ava Prieto

Honors Theses and Capstones

Inhibitory control, a central component of executive function, is the ability to suppress unwanted actions in response to a stimulus (Verbruggen et al., 2014; Verbruggen et al., 2019) and is one of the best indicators of executive task management as well as the ability to prevent unwanted prepotent responses. This capacity is essential for goal specific behavior and for responding flexibly to challenges. The present study examined the effects of voluntary wheel running on inhibitory control in two cohorts of Long-Evans rats using a rodent variant of the canonical stop-signal task. We found that rats with access to an active …

A Cross-Species Meta-Analysis Of Environmental Enrichment Effects On Cognition, Greg S. Fitzgerald

Electronic Theses & Dissertations (2024 - present)

Environmental enrichment --providing animals or people with stimulating, complex surroundings --consistently improves cognitive performance in laboratory rodents. But when similar interventions are tested in humans, the benefits are much smaller. Understanding why matters: if researchers overestimate how well rodent findings will translate, it can mislead expectations for human cognitive interventions.

This dissertation presents the first cross-species meta-analysis comparing environmental enrichment effects on cognition between rodent and human studies. Drawing on 121 studies (71 rodent, 50 human) contributing 478 effect sizes, the analysis used multilevel models with variance correction to account for the statistical dependence created when studies report multiple outcomes. …

Channel-Opening Kinetics Of Complex Kainate Receptors, Noah S. Saunders

Electronic Theses & Dissertations (2024 - present)

Ionotropic glutamate receptors (iGluRs) are found both pre- and postsynaptically in neuronal membranes, and mediate the majority of fast excitatory synaptic transmission in response to the binding of glutamate, a major excitatory neurotransmitter in the central nervous system (CNS). Ionotropic glutamate receptors are divided into three distinct subtypes: kainate, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), and N-methyl-D-aspartic acid (NMDA) receptors. Auxiliary proteins specific to each receptor subtype also play a role in tuning both receptor expression and gating properties, such as neuropilin and tolloid-like (NETO) proteins that modulate kainate receptors, and transmembrane AMPA receptor regulatory proteins (TARPs) that regulate AMPA receptors. Like …

Photo And Spatial Control Of Rna Structures And Functions: Exploring Positional Effects And Photo-Responsiveness Of Azobenzene Modified Nucleotides, Jinxi Du

Electronic Theses & Dissertations (2024 - present)

RNA molecules perform many important biological functions by forming complex three-dimensional structures stabilized by base pairing, tertiary interactions, and metal ion coordination. Because RNA function depends strongly on its structure, methods that allow reversible control of RNA conformation and activity are important for understanding RNA behavior and for potential therapeutic applications. However, achieving reversible and site-specific control of RNA structure, especially at the single-nucleotide level, remains challenging. In this dissertation, I developed and applied azobenzene-modified nucleotides as a chemical tool to enable optical and spatial control of RNA structure and function.

The first part of this dissertation focuses on establishing …

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 …

Barriers And Corridors: Timber Rattlesnake Habitat Connectivity In New York, Lauren Rose

Electronic Theses & Dissertations (2024 - present)

Habitat fragmentation poses a significant threat to species that rely on landscape connectivity for movement in search of food, water, and mates. The timber rattlesnake (Crotalus horridus), listed as a threatened species in New York State, travels an average of 1.5 miles—and up to five miles—from permanent denning sites to reach habitat suitable for gestation, foraging, basking, and overwintering. Ongoing development in the lower Hudson Valley has increasingly fragmented these critical habitats, restricting movement between den populations. This thesis evaluates landscape barriers that contribute to population isolation and identifies opportunities to restore connectivity among timber rattlesnake metapopulations.

Using …

Mechanisms Of Glyphosate Toxicity: Uptake, Mitochondrial Function, And Metabolism, Dionysios Patriarcheas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glyphosate, the most widely used herbicide in the world, is an inhibitor of chorismate biosynthesis, the precursor of aromatic amino acids. The target of glyphosate is absent in animals, but findings reporting toxicity in model organisms without a known mechanism or target are increasing. Saccharomyces cerevisiae is a useful and versatile model for understanding molecular mechanisms of toxicity. In yeast, previous work has shown that the aspartate/glutamate permease Dip5 is the proposed transporter for glyphosate and that mitochondrial metabolism has been implicated in response to glyphosate toxicity. This dissertation aimed to identify the effects of glyphosate on mitochondrial function through …

Does Diverse Seeding Adoption Reduce Production Costs? The Case Of Diverse Forage Seeding Strategies In West Virginia., Ivan Andres Wong

Graduate Theses, Dissertations, and Problem Reports (ETD)

Feed and harvested forage represent a major share of production costs in Appalachian cow-calf systems, where a pronounced summer forage gap forces producers to rely on purchased hay. This thesis evaluates whether adopting diverse forage seeding strategies reduces production costs relative to the existing pasture management practice, accounting for the spatial heterogeneity of West Virginia’s production environments. The analysis proceeds in two steps. First, an unsupervised K-means clustering of 14 farms enrolled in the NRCS Conservation Innovation Grant field trial groups the farms into two agroclimatic clusters, Highland-Cool and LowlandWarm, using elevation, growing-season Growing Degree Days, growing-season precipitation, and soil …

Dielectrophoretic Biomarkers For Cancer Detection And Cell Analysis: Integrating Microfluidics And Ai, Raphael Olumide Oladokun

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pancreatic ductal adenocarcinoma (PDAC) carries a five-year survival rate of 13%, driven largely by late-stage diagnosis and the absence of sensitive noninvasive screening tools. Current diagnostic methods lack the sensitivity to detect disease-associated systemic changes at early and precancerous stages, representing a critical clinical gap. This dissertation addresses the central hypothesis that PDAC and its pathological subtypes induce measurable, disease-associated electrophysiological changes in circulating PBMCs that can serve as correlative liquid-biopsy biomarkers. To test this hypothesis, this work asks: can dielectrophoresis (DEP), impedance and zeta potential analysis with AI-assisted classification distinguish benign pancreatic conditions (non-malignant control), precancerous lesions (primarily IPMNs), …

An Assessment Of Disease Risks, Population Genetics, And Spatial Ecology Of Appalachian Cottontails (Sylvilagus Obscurus) And Snowshoe Hares (Lepus Americanus) In West Virginia, Usa, Madison Leigh Miller

Graduate Theses, Dissertations, and Problem Reports (ETD)

Snowshoe hares (Lepus americanus) occupy a large range across the United States and Canada. While snowshoe hare populations are generally considered stable in the interior of their range, populations along range edges are experiencing declines, possibly driven by climate-related factors such as seasonal coat color mismatch. West Virginia represents one of the southernmost extents of the species’ range, yet little is known about the population genetic status or population sizes of snowshoe hares in the state. Appalachian cottontails (Sylvilagus obscurus) are another lagomorph species found in West Virginia. This species experienced a historical decline and currently …

The Histamine-3 Receptor In Cardiac Fibrosis: A Novel Role In Fibroblast Function, Heather Linsky

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the United States, heart failure affects approximately 6.7 million individuals. Despite a number of available therapies, heart failure prevalence continues to grow, suggesting the need for a broader range of effective therapies. More specifically, heart failure with preserved ejection fraction comprises approximately 50% of all heart failure cases and, as the name suggests, is a disease of diastolic dysfunction as opposed to systolic dysfunction. A hallmark of heart failure with preserved ejection fraction is myocardial fibrosis, which is a key contributor to diastolic dysfunction, and is the major focus of this dissertation work. In the heart, histamine-3 receptor activation …

Ornithine Metabolism In Retinal Pigment Epithelium And Retina And Implications In Gyrate Atrophy, Artjola Puja

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ornithine aminotransferase (OAT) is a mitochondrial enzyme that regulates ornithine metabolism by converting ornithine to pyrroline-5-carboxylate, a precursor for proline and glutamate synthesis. Deficiency of OAT causes systemic ornithine accumulation and leads to gyrate atrophy (GA) of the choroid and retina, a hereditary disorder characterized by progressive chorioretinal degeneration and irreversible vision loss. Chorioretinal atrophy typically starts at the mid-peripheral retina and progresses toward the macula. Although elevated ornithine is considered toxic to the eye, how ornithine is metabolized in ocular tissues and why OAT deficiency causes selective, region-specific vulnerability remain unclear. We combined ex vivo and in vivo stable …

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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 need to measure their glucose levels in order to determine how much insulin or medicine …

Optimization Of Feed Manufacturing Productive Capacity, Feed Quality, And Feed Safety Utilizing A Variety Of Pellet Die Parameters, Feed Additives, Conditioning Specifications, And Simulated Feed Bin Storages, Lucas Edward Knarr

Graduate Theses, Dissertations, and Problem Reports (ETD)

In Chapter 2, an experiment was conducted to determine if the inclusion of 1.50% mixer-added water (MAW) and/or 0.25% Azomite^® (AZM) would be suitable in alleviating concerns regarding pellet production rate and pellet quality when manufacturing feed with low-moisture corn. Furthermore, the authors aimed to determine if these additives had varying effects when utilizing different pellet die thicknesses. A 2 (Azomite; 0.00% or 0.25%) x 2 (mixer-added water; 0.00% or 1.50%) x 3 (pellet die thickness; 32 mm, 38 mm, or 45 mm) factorial arrangement was utilized to create the twelve experimental treatments, each manufactured …

Genomic Variation, Adaptive Evolution, And Invasive And Evolutionary History Of Microstegium Vimineum, Cameron William Corbett

Graduate Theses, Dissertations, and Problem Reports (ETD)

Invasive species can cause environmental and economic damage, but can offer unique opportunities to study rapid evolution and adaptation in novel environments. Microstegium vimineum (stiltgrass) is a prolific invasive grass in the eastern United States. Historical herbaria collections were used to identify patterns of invasion history and population dynamics over a spatial and temporal scale. Analyses of plastid genomes reveal a complex invasion history, including a single introduction in the southern United States linked to Japan and multiple repeated introductions in the northern United States from various source populations. Spread of introduced populations provide evidence of admixture among previously geographically …