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A 16s & Its Soil Microbiome Analysis Of Native & Old-World Bluestem Invaded Soils Of Kansas Grasslands, Zachary Nelson

Master's Theses

Invasive species are becoming an increasing problem throughout the world. Their effect on local ecosystems is detrimental and widespread, harming productive efforts such as biomass accumulation, forcing native species (plant, animals, microbes) out, and ultimately, reducing biodiversity. Investigations of how invasive plants spread are widely studied; however, there has been little to no examination of how native plants influence the microbiome in the surrounding soil. In this study, I performed a fungal and bacterial metagenomic analysis of the soil and root microbiomes of both native grasslands and grasslands invaded by Old-World Bluestem Grasses to help determine if they influence the …

The Impact Of Planting Season And Crop Residue On Germination, Reproductive Success, And Mass Of Native Forbs, Michaela Vonlintel

Master's Theses

The lack of biodiversity in prairie restorations compared to native prairies is alarming, and restoring this diversity has been a key focus of research and restoration projects for years. This study aims to assess two variables: planting season and plant residue, for achieving success in forb establishment. This research was conducted in a greenhouse using mesocosms that were seeded in spring, summer, and fall with nine forb species. Half of each seasonal treatment received ground cover, while the other half did not. Two hypotheses were formed. The first was that the fall planting will be the most successful seasonal treatment …

Effects Of Aggressive Reed (Phragmites Australis) On Aquatic Communities In A Kansas Reservoir, Allison Pardis

Master's Theses

Phragmites australis is an Aquatic Nuisance Species (ANS) in Kansas, a non-native reed that threatens lake and river ecology, displaces desirable species, impedes movement of wildlife and humans, that can have detrimental economic effects on communities. The majority of Phragmites research is in brackish ecosystems and the effects of Phragmites in freshwater systems and especially on fishes is undocumented, even as many states and agencies invest substantial resources in management. As freshwater systems face a biodiversity crisis, prevention and control of invasive species is critical. Effective management therefore requires a thorough understanding of the effects these invaders have on ecosystems …

Effects Of Lipopolysaccharide On Mandibular And Tibial Bone Regenerationin A Murine Model Of Sle Induced By Fcγriib Deficiency, Sirikanda Jantaboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Although systemic lupus erythematosus (SLE) is known as the autoimmune disease that triggers inflammation and bone impairment, the mechanisms leading to the decrease in bone regeneration remain inadequately characterized. Patients with SLE have been observed high prevalence in bone loss due to host immune responses that may induce host antimicrobial activities. Here, this study used systemic and local lipopolysaccharide (LPS) administration for mimicking infectious condition in FcγRIIB−/− mice as a lupus murine model. The results showed FcγRIIB lacking FcγRIIB−/− in mice with local and systemic LPS led to decreased cancellous bone volume in their drilled hole region of tibial and …

Eastern Redcedar (Juniperus Virginiana L.) Encroachment On South-Central South Dakota Rangelands: Impact On Plant Communities, Austin K. Domeier

Electronic Theses and Dissertations

Grasslands historically covered 46 million km2 of Earth’s surface representing nearly 42% of the living vegetation. Encroachment of woody species onto grasslands and savannas is a widely researched global phenomenon, with eastern redcedar (ERC) (Juniperus virginiana L.) trees being the most prominent woody encroacher in the Northern Great Plains (NGP) due to the lack of prescribed fire and planted ERC escaping from shelterbelts. This encroachment poses a threat to native plant communities in terms of their reproduction, regeneration, and diversity. ERC are fierce competitors and can establish in most soil types, are drought tolerant, and prolific seed reproducers. These qualities …

Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain

Electronic Theses and Dissertations

Conservation management practice adoption on agricultural land has increased in recent years due to increasing public and private investment. The anticipated impact of increasing conservation management practice adoption are reduced greenhouse gas emissions and improved soil, water, and air quality. Understanding how these conservation management practices affect agricultural producers economically is vital to properly incentivize these practices. The existing literature on how conservation management practices affect soil health and crop yields is mixed and generally has been conducted on experimental research stations. These studies may not fully account for the on-farm effects of conservation management practices. The objectives of this …

Pre-Exposure Of Escherichia Coli And Staphylococcus Aureus To Sub-Bactericidal Concentrations Of Benzalkonium Chloride And Its Effect On Low-Level Antimicrobial Resistance, Logan Fette

All Graduate Theses, Dissertations, and Other Capstone Projects

Antimicrobial resistance that develops in bacteria is a highly studied aspect of microbiology due to the concerns that it poses for public health. Antibiotics remain our primary care option when dealing with bacterial infections. The concept of tolerance of bacteria to disinfectants is similar and it also poses a significant health risk. Since use of disinfectants for sanitation is a primary manner in which we are able to prevent potential infections from occurring in the first place, it can be a helpful means to preventing development of antimicrobial resistance. However, what has not been explored to the same extent is …

Geographic Variation Of Desiccation Resistance In Rhagoletis Zephyria (Diptera: Tephritidae) In The Pacific Northwest: An Adaptive Response To Local Bioclimate, Nathan Roueche

WWU Graduate School Collection

Species with broad distributions exist in heterogenous landscapes and therefore must be able to maintain key physiological processes under a variety of abiotic conditions. This can lead to localized variation in phenotypes associated with environmental cues. Atmospheric water loss is a major source of physiological stress for terrestrial insects and one which is predicted to have major implications for biodiversity under future climate scenarios. Understanding which species exhibit adaptive variation can provide crucial insights into how individual species and thus ecological communities have evolved to cope with changing climate conditions as well as inform predictions as to how they may …

Foraging Ecology Of Sexually-Dimorphic Marine Generalist Predators: Describing Stellar Sea Lion Diet Along The Northern Washington Coast, Zöe Kathryn Lewis

WWU Graduate School Collection

Understanding generalist predator impact on prey populations requires an understanding of predator diet composition, foraging ecology and specialization, all of which may vary over spatial and temporal scales. Steller sea lions (Eumetopias jubatus) are large, sexually dimorphic, generalist predators that may have different roles in the ecosystem based on sex. However, the variation between individuals within a population, or intrapopulation feeding diversity of Steller sea lions has not been examined. In this study, I describe the diet of Steller sea lions along the northern coast of Washington between December 2020-August 2021 using DNA metabarcoding, hard parts analysis, and qPCR sex …

The Correlation Between Acl Injury & Concussion, Brandon Michael Phillips

Theses and Dissertations--Kinesiology and Health Promotion

Concussion (also known as mild traumatic brain injury) is a neurological injury that occurs after a blow to the head or neck area and can have affects to movement based on the severity of the injury. Mild traumatic brain injury has possible linkage to an increased risk of anterior cruciate ligament (ACL) injury. The purpose of this thesis was to assess the impact of prior concussion on lower extremity mechanics that are associated with risk of ACL injury. A total of 11 individuals with prior history of concussion and 11 healthy individuals without prior history of concussion (56.5 months since …

Epigenetic Buffering In Introduced House Sparrows, M. Ellesse Lauer

Electronic Theses and Dissertations

Epigenetic buffering, as an environmentally induced increase in variance of epigenetic states that increases phenotypic variation to buffer populations against decreased fitness, may be a factor that resolves the genetic paradox of introduced species. DNA methylation is a molecular mechanism that could facilitate epigenetic buffering by changing in response to environmental stress. Therefore, epigenetic buffering can be detected through increased variance in DNA methylation in novel or heterogeneous environments. Introduced house sparrows (Passer domesticus) have well-documented phenotypic changes with low genetic diversity, high epigenetic diversity, and high variance in DNA methylation that provide a characteristic signature of epigenetic buffering. …

Primary Cilia Display A Non-Uniform Response To Intracellular Calcium Release, Hannah R. Fisher

WWU Graduate School Collection

Cilia are microtubule-based organelles that project from the surface of individual cells. When cilia are formed, they are nucleated from centrioles that are known as basal bodies. Microtubules elongating from the basal body give rise to the axoneme of the cilium, which gives cilia their rod-like structure. The axoneme is surrounded by a specialized plasma membrane that is unique, but continuous with the plasma membrane that surrounds the rest of the cell. The ciliary membrane is enriched with ion channels and membrane-bound proteins that are essential for cilia function. Interestingly, the cilium maintains a distinct environment from the rest of …

Microbial Community Dynamics During Key Life History Transitions In The Deep-Sea Chemosymbiotic Mussel, Gigantidas Childressi, Tessa F. Beaver

WWU Graduate School Collection

Marine invertebrates form specific associations with bacterial communities that are different from their environment, change throughout their development, and shape evolutionary and ecological processes. The bathymodiolin (Mytilidae) mussel Gigantidas childressi lives at deep-sea methane seeps and relies on methanotrophic endosymbionts for its nutrition. Its larval life, however, is spent feeding in the water column. Upon metamorphosis at a suitable seep habitat, methanotrophic bacteria rapidly colonize gill cells and the juvenile mussel switches to symbiont-derived energy. To determine if the microbiome of the G. childressi changes during these transitions, the V3/V4 region of the 16S rRNA gene was sequenced to census …

Investigating Mechanisms Of Injury And Intervention In A Novel In Vitro Model Of Traumatic Brain Injury In Organotypic Hippocampal Slice Cultures, Julia Elaine Jagielo-Miller

Theses and Dissertations--Psychology

Traumatic brain injuries (TBIs) impact millions of individuals each year and can pose long term consequences. Despite numerous attempts, no medication has been approved by the FDA to treat TBIs. The causes of these failed trials are multifaceted, but in part can be attributed to the complex nature of TBIs, as well as a lack of sufficient pre-clinical data. In vitro models of TBI are an important tool to help understand the cellular changes seen following the injury, in a highly controlled environment. For the following experiments, a novel model of TBI was used to injure organotypic hippocampal slice cultures, …

Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland

Electronic Theses and Dissertations

Little information is available concerning the distribution of genetic diversity in non-salmonid, non-imperiled, freshwater fish. In order to fill in this knowledge gap, I conducted a population genomics survey in Redbreast Sunfish (Lepomis auritus; RBS), a widespread, generalist species distributed along the Atlantic slope rivers of eastern North America. I sampled four basins (ACF, Savannah, Roanoke, and James) at eight sites each with a factorial experimental design. Sites were distributed among coastal plain, Piedmont, or mountain ecoregions in order to capture the greatest range of environmental states experienced by RBS, with the intention of finding evidence for local adaptation to …

Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover

Electronic Theses and Dissertations

The synthesis of palladium nanoparticles (Pd NPs) using materials-directed peptides is a novel, nontoxic approach which exerts a high level of control over the particle size and shape. This biomimetic technique is environmentally benign, featuring nonhazardous ligands and ambient conditions. Nanoparticles are extremely reactive catalysts, boasting a large surface-to-volume ratio when compared to their bulk counterparts. The rational design of these nanoparticles using peptides has been very successful in aqueous environments, but no research has been done to apply it in organic systems. As such, the biomimetic synthesis of Pd NPs in an organic system is here investigated, with ethanol …

Effects Of Physiological Stage And Diet On Drosophila Suzukii Olfaction, Aerianna Shindindowi Littler

Theses and Dissertations--Entomology

Massive economic damage by spotted-wing drosophila (SWD), Drosophila suzukii, results from their unique egg laying behavior. Gravid SWD flies employ a complex suite of behaviors to find fruit with the optimum firmness and chemistry. We tested for SWD attraction to various fruits and found overripe raspberries to be most attractive to gravid flies which was unexpected since they oviposit in ripe fruit. We next tested the same choice assay in a T-maze and found that the results were comparable. We also found discrete odor profiles among the ripening stages. When testing for sugars and CO2 concentrations from field-collections, overripe …

Synthesis Of 6,6- And 7,7-Difluoro-1-Acetamidopyrrolizidines And Their Oxidation Catalyzed By The Nonheme Fe Oxygenase Lolo, Nabin Panth

Theses and Dissertations--Chemistry

One of the remarkable steps in loline alkaloid biosynthesis is the installation of an ether bridge between two unactivated C atoms in 1-exo-acetamidopyrrolizidine (AcAP). LolO, a 2-oxoglutarate-dependent nonheme Fe oxygenase, catalyzes both the hydroxylation of AcAP and the resulting alcohol's cycloetherification to give N-acetylnornoline (NANL). The mechanism of hydroxylation is well understood, but the mechanism of the oxacyclization is not. I synthesized difluorinated analogs of AcAP in an attempt to further understand the mechanism of the unusual cycloetherification step.

I prepared 6,6-F₂-AcAP in eight steps from N,O-protected 4-oxoproline. The key step was a Dieckmann …

Structural Basis Of Bacterial Flagellin For Naip5 Binding And Nlrc4 Inflammasome Activation And The Mechanism Of Flagellin Induced Release Of Cytokines In Vivo, Jian Cui

Theses and Dissertations--Chemistry

The bacterial flagellum is a whip-like structure that protrudes from the cell membrane and is one of the most complex and dynamic biological molecular machines that propels bacteria to swim toward beneficial environments and the sites of infection. It is composed of a basal body, a hook, and a long filament. The flagellar filament contains thousands of copies of the protein flagellin (FliC) monomer arranged helically and ending with a filament cap composed of oligomer protein FliD. The overall structure of the filament core is preserved across bacterial species, while the outer domains exhibit high variability, and in some cases …

Antibiotic Permeation In Gram-Negative Bacteria And Contribution Of Inflammasome Activation And Pyroptosis In Pathogenesis Of Salmonella Systemic Infection, Ankit Pandeya

Theses and Dissertations--Chemistry

Antibiotic resistance is one of the major global issues in the field of public health and medicine. Good antibiotic candidates need to be selectively toxic, inhibit cellular target, and effectively penetrate and accumulate in bacterial cells. The last factor is a formidable barrier in the development of antimicrobials effective in Gram-negative bacteria, due to the presence of two layers of cell envelope. The first half of my thesis focuses on understanding the permeation of small molecules through this formidable cell envelope, distribution inside the cell of Gram-negative bacteria, and design of novel methods to make small molecules effectively cross the …

The Role Of Charge On Dna Packaging And Integrity Within Reconstituted Peptide-Dna Assemblies, Ehigbai Oikeh

Theses and Dissertations--Chemistry

In nature, DNA exists primarily in a highly compacted form. The compaction of DNA in vivo is mediated by cationic proteins; histone in somatic nuclei and arginine-rich peptides called protamines in sperm chromatin. The packaging in the sperm nucleus is significantly higher than somatic nuclei resulting in a final volume roughly 1/20^th that of a somatic nucleus. This tight packaging results in a near crystalline packaging of the DNA helices. While the dense packaging of DNA in sperm nuclei is considered essential for both efficient genetic delivery as well as DNA protection against damage by mutagens and oxidative species, …

Development Of Fluorescence Based Approaches To Understand Astrocyte Biology In The Context Of Nicotine And Nicotinic Receptor Activity, Surya P. Aryal

Theses and Dissertations--Chemistry

Smoking and tobacco use (STU) is a major global health problem and worldwide more than six million people die due to tobacco related diseases each year. Although majority of smokers try to quit smoking several times in their life, traditional therapeutic approaches, which focus only on neuronal cells, have a very low success rate. Understanding the effect of nicotine on glial cells, synaptic communication and blood vasculature in the brain can provide further insights on the neurobiology of substance abuse and can potentially help to design better therapeutic approaches. Glial cells are non-excitable cells in the brain which do not …

Evaluation Of Hemp Seed Meal As A Fish Meal Replacement Through Growth And Digestibility Trials In Striped Bass (Morone Saxatilis), Anthony Sample

Electronic Theses and Dissertations

Demand for seafood has continued to increase despite a stagnation in global wild-caught fisheries. Aquaculture has met this demand but suffers from numerous sustainability issues because of dependence on fish meal, which is unsustainable, sparking nutritional research into alternatives. Hemp seed meal has shown promise as an alternative due to its sustainable production and nutritional qualities. This study evaluated hemp seed meal as an alternative to fish meal through growth and digestibility trials with Morone saxatilis. A seven-week growth trial was conducted within a recirculating aquaculture system using a total of two control diets (commercial and constructed) and six …

The Impact Of Gloves And Simulated Occupational Tasks On Handgrip Strength In Structural Firefighters, Sarah Lanham

Electronic Theses and Dissertations

Adequate handgrip strength (HGS) is important to safely and effectively perform fireground tasks. However, there is limited research describing the deleterious impact of glove use and fatigue from occupational tasks on HGS. Therefore, the aims of this investigation were to quantify the impact of glove use and occupational tasks on HGS, to explore the relationship between HGS versus the glove and task-induced decrement in HGS, and to evaluate the relationship between HGS and decrement in HGS versus occupational performance. Fourteen (Males: n=13) career structural firefighters performed a maximal isometric HGS assessment with and without gloves before and immediately following completion …

Investigating The Effect Of A Facultative Symbiont, Hamiltonella Defensa, On Pea Aphid, Acyrthosiphon Pisum, Fecundity And Behavior In Elevated Co₂ Atmospheres, Tyler J. Follman

Electronic Theses and Dissertations

As atmospheric carbon dioxide (CO₂) levels continue to rise, it is important to study how economically important organisms, like the pea aphid, Acyrthosiphon pisum, will react to these conditions. The pea aphid feeds on the phloem of crop plants like alfalfa, peas, and fava beans, where it not only directly harms the plant but also can spread plant viruses. A wide variety of factors can influence pea aphid fecundity and behavior. Some of these factors are abiotic, like atmospheric conditions, and some are biotic, like microorganisms with which the pea aphid has a mutualistic relationship. In this thesis, …

Stress, Stress Appraisal And Coping In Athletic Trainers During The Covid-19 Pandemic, Lawson Holton

Electronic Theses and Dissertations

Introduction: There have been many studies conducted on the stress and mental health of frontline healthcare workers (HCWs) over the past months since the COVID-19 pandemic began. Very limited literature has examined the effect of the pandemic on athletic trainers (ATs). Objective: The aim of this investigation was to examine the stress, stress appraisal, and coping measures of ATs during the COVID-19 pandemic. Methods: Participants were recruited members from the National Athletic Trainers’ Association (NATA). The Perceived Stress Scale-10 was used to measure stress, the Stress Appraisal Measure was used to measure stress appraisal, and the Brief COPE was used …

Mechanisms And Treatment Of Pain-Depressed Behavior In Male And Female Mice, Clare M. Diester

Theses and Dissertations

One of the largest discrepancies between preclinical and clinical assessment of pain and analgesia is the type of behavioral endpoint used. Although most preclinical research has historically focused on drug effectiveness to block reflexive withdrawal behaviors stimulated by a noxious stimulus, increasing evidence shows that drug-induced restoration of pain-depressed behaviors provides increased clinical translation with decreased susceptibility to false-positives. Accordingly, the first portion of this dissertation designed a behavioral battery that featured pain-depressed behaviors as well as more conventional pain-stimulated behaviors for testing candidate analgesics in male and female mice. The main findings are as follows. (1) Intraperitoneal injection of …

The Role Of Irf-1 In Spontaneous Mouse Glioma, Aakash B. Vaidya

Theses and Dissertations

Glioblastoma Multiforme has been shown to be one of the deadliest primary brain cancers. One of the reasons why GBM is so deadly, is a unique immunosuppressive tumor microenvironment that promotes GBM growth and progression. Both astrocyte and microglia have been implicated in immunosuppression. In this study, we explored the role of Interferon Regulatory Factor 1 (IRF-1) in astrocytes and glioma cells on the growth of spontaneous glioma tumors. IRF-1 is regulated by the JAK/STAT pathway and induces expression of Programmed death ligand 1 (PD-L1). PD-L1 downregulates immune responses to glioma. We found that IRF-1 had no effect on spontaneous …

Alternatively Spliced Csf3r In Human Health And Disease, Borwyn A. Wang

Theses and Dissertations

Elevated alternative colony stimulating factor 3 receptor (CSF3R) isoforms are observed in myelodysplastic syndromes (MDS) and other myeloid neoplasms, but their role in driving disease progression has not been fully explained. In this study we report on the role of an MDS-associated splicing factor SRSF2 and its effects on the production of Class III and Class IV CSF3R isoforms and granulopoiesis. Class IV add-back in Csf3r-null mice showed impaired neutrophil differentiation with increased number of CFU-G, which largely consisted of metamyelocytes, while Class III showed greater dysgranulopoiesis accompanied by dysmorphic neutrophils. Alternative CSF3R isoforms were elevated in …

Coupled Structure-Function Responses To Disturbance: High Structural Complexity Resistance Supports Primary Production Resistance, Kerstin M. Niedermaier

Theses and Dissertations

The capacity of forests to resist structural change and retain material legacies–the biotic and abiotic resources that persist through disturbance–is crucial to sustaining ecosystem functioning after disturbance. However, the role of forest structure as both a material legacy and feature supporting carbon (C) cycling stability following disturbance has not been widely investigated. We used a large-scale disturbance manipulation to ask whether LiDAR-derived canopy structures as material legacies drive 3-year responses of NPP to a range of disturbance severity levels. As part of the Forest Resilience Threshold Experiment (FoRTE) in northern Michigan, USA we simulated phloem-disrupting disturbances at a range of …