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Strawberry Disease Management Improvement For Macrophomina Root Rot And Botrytis Fruit Rot, Yu-Chen Wang

Master's Theses

Strawberry production in California is limited by plant diseases such as Macrophomina root rot (caused by Macrophomina phaseolina) and Botrytis fruit rot (BFR) (caused by Botrytis cinerea). Current disease management strategies are compromised due to fumigant regulations or ineffective disease management practices. This thesis investigated methods to potentially improve the management of these two diseases.

Host plant resistance evaluations for Macrophomina root rot were conducted for the 2020-2021 and 2021-2022 growing seasons. Fifty-one strawberry genotypes were screened in two field experiments where plants were inoculated artificially with Macrophomina phaseolina in both seasons. A wide range of plant resistance …

Population Genetics Of Cownose Rays, Rhinoptera Spp. In The Western Atlantic, Helen Weber

Master's Theses

Using molecular tools (e.g., the NADH subunit II mitochondrial gene), this study was the first to document the Brazilian cownose ray, Rhinoptera brasiliensis, within the northwestern Atlantic (NWA), and was the first study to examine population structure in R. brasiliensis within the NWA or northern Gulf of Mexico (GMX), revealing novel insights into the population biology of the animal and extending its range by nearly 1,500 km. This study also examined the sympatrically occurring American cownose ray, R. bonasus, and found population structure between the NWA and the GMX and the NWA and the southwestern Atlantic (SWA). High …

Evolving Deforestation Narratives In Practice: A Study Of The Un-Redd+ Readiness Programme In Nigeria, Stuart Clive Blackwell

Master's Theses

The UN-REDD+ Readiness Programme was conducted between 2009 and 2015. The REDD+ Programme in Nigeria began once the readiness program was completed. This study conducts a document analysis of the program utilizing a political ecology lens to determine the extent to which the program adheres to or strays away from critical narratives surrounding both drivers of deforestation and inclusion and autonomy of federal, state, and local communities. By examining the entirety of the available documentation of the REDD+ Readiness program in Nigeria using a political ecological lens, this study demonstrates both an evolution of the program itself, and an evolution …

Changes In The Morphology Of Widgeon Grass (Ruppia Maritima) With The Onset Of Reproduction And Impacts On Fish Assemblages At The Chandeleur Islands, La, Matthew Byrnes

Master's Theses

Seagrasses are important submerged coastal habitats that support nearshore communities. Ruppia maritima (widgeon grass) is a widespread species whose leaves branch extensively when reproductive. The goal of this study was to understand use of reproductive and non-reproductive R. maritima by fishes, recognizing the morphological change undergone by the plant when flowering. During the peak reproductive season in August and September 2021, R. maritima meadows at the Chandeleur Islands, LA were sampled to describe the spatial distribution and morphology of reproductive plants and investigate habitat use by fish assemblages. We assessed spatial trends in R. maritima presence and occurrence of reproduction …

Tropical Cyclone Storm Surge Detection In Slash Pine Radial Growth Along The Northern Gulf Of Mexico Coastline, Alyssa C. Crowell

Master's Theses

My thesis examines the ecological impact of tropical cyclone (TCs) storm surge on coastal slash pine (Pinus elliottii var. elliottii Engelm) communities along the Gulf of Mexico in the southern United States (U.S.). Previous research has shown slash pine radial growth trends can be examined to identify long and short-term growth changes associated with TC passage, providing insight into overall stand health and resiliency through time. However, this previous research encompasses just one site in Mississippi. My thesis expands the spatial footprint of TC-surge impact on slash pine radial growth with the addition of three new sites.

I examined …

Sedimentary Characteristics And Associated Carbon And Nutrients Of Overbank Sediments Deposited During The 2018, 2019, And 2020 Floods In Embanked Floodplains Along The Lower Mississippi River Near Natchez, Mississippi, Rachel Kelk

Master's Theses

The Lower Mississippi River (LMR) experienced major floods in 2018, 2019, and 2020. Sediment deposition in the embanked floodplains during floods represent important storage and sequestration opportunities for carbon and nutrients from ~40% of the continental USA. This research aims to compare depositional thicknesses, organic matter (OM), carbon (C), nitrogen (N), phosphorous (P) concentrations, and grain sizes in floodplain sediments deposited by the combined 2018-19 floods to the 2020 flood along the LMR near Natchez, Mississippi. Greater depositional thicknesses in 2018-19 are best explained by their combined flood durations; the 2019 flood was the longest in recorded history. Slightly higher …

Disturbance Ecology Of The Sonadora River Rock Pool Insect Assemblage At Luquillo Experimental Forest, Puerto Rico, Patrick Gilkey

Master's Theses

Freshwater rock pools can serve as habitat for aquatic insects. Flash-flooding can have profound effects on insect communities in streams and rivers, but these effects have not been studied on freshwater rock pools. The goal of this thesis was to describe ecological patterns of the Sonadora River rock pool insect community at the Luquillo Experiment Forrest, Puerto Rico, specifically in response to intense flash-flooding, and then perform experiments to elucidate possible processes to explain those patterns. The rock pools contained primarily three taxa of Dipteran (true-fly) larvae, in order of decreasing abundance, 1) a newly discovered species of ceratopogonid (biting …

Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black

Master's Theses

The Appalachian Mountains have a complex geologic history spanning three orogenic periods, the Taconic, the Acadian/Neoacadian, and Alleghanian orogenies. The Inner Piedmont of the Appalachian Mountains within Alabama contains two distinct lithologic complexes, the Dadeville Complex, and the Opelika Complex separated by the Stonewall Line. These complexes were formed during an arc-back arc fringing system during the Taconic orogeny and emplaced and recorded peak metamorphism during the Acadian orogeny.

The Dadeville Complex is an allochthonous arc terrain built on extended Laurentian crust. The mode of transportation and accretion after formation is not well understood, which has implications for the role …

Psychosocial Maturity And Alcohol Outcomes: The Mediating Role Of Alcohol Protective Behavioral Strategies, Skyler Hoover

Master's Theses

The present study evaluated the mediating role of alcohol protective behavioral strategies on the relationship between temperance, responsibility, perspective (i.e., the facets of psychosocial maturity) and alcohol use outcomes. Potential invariant paths among graduate and undergraduate students were also explored. All participants were undergraduate and graduate students at the University of Southern Mississippi aged 18 to 25. Participants reported demographic information and completed measures of temperance, responsibility, perspective, alcohol use, and alcohol consequences. Results indicated the full mediation model showed poor fit the data; greater temperance predicted greater alcohol protective behavioral strategy use, greater responsibility and perspective predicted less alcohol …

Efficacy Of Chemical And Biological Stump Treatments For The Control Of Heterobasidion Occidentale Infection Of California Abies Concolor, Adrian Luis Poloni

Master's Theses

We conducted an experimental evaluation of treatments to limit Heterobasidion occidentale infection of white fir (Abies concolor) stumps and wounds in California mixed conifer forests. We tested the efficacy of urea, borate, and a mixture of two locally collected Phlebiopsis gigantea strains in preventing pathogen colonization of fir stumps and separately, urea and borate as infection controls on experimental stem wounds. These were paired with a laboratory test on ~100 g wood blocks with and without a one-week delay between inoculation and treatment. Urea, borates, and Phlebiopsis treatments all significantly reduced the stump surface area that was colonized …

The Effects Of Cofermentation Of Cider And Apple Pomace On Cider Attributes, Abigail D. Affonso

Master's Theses

Phenolics are critical to the sensory attributes and health benefits of hard cider due to their contribution to the flavor, mouthfeel, and antioxidant activity. With the increase in demand for cider, the use of dessert apple varieties has become more common leaving ciders lacking in phenolics. However, a promising method to increase their phenolic content is through maceration with apple pomace. This study evaluated the effect maceration with apple pomace during cider fermentation on the extraction of phenolic compounds, as well as its effect on the sensory properties of the final product. For this study, ciders were fermented with 0% …

Impact Of Incorporating Intuitive Eating Principles Into A College Nutrition Course On Eating Behaviors, Kira L. Minot

Master's Theses

Objective: This study aimed to assess the impact of an online introductory college nutrition course that implements evidence-based intuitive eating (IE) concepts and principles on students’ application of IE behaviors. A secondary outcome explored the relationship between student grades and changes in IE behavior implementation. Researchers hypothesized an increase in the average use of IE practices post-intervention.

Methods: This study was a non-randomized pilot intervention using pre- and post-test surveys. Enrolled students completed the intuitive eating scale-2 (IES-2) survey on the first and last days of the 16-week course. Students participated in typical nutrition coursework throughout the semester with the …

Unique Signed Minimal Wiring Diagrams And The Stanley-Reisner Correspondence, Vanessa Newsome-Slade

Master's Theses

Biological systems are commonly represented using networks consisting of interactions between various elements in the system. Reverse engineering, a method of mathematical modeling, is used to recover how the elements in the biological network are connected. These connections are encoded using wiring diagrams, which are directed graphs that describe how elements in a network affect one another. A signed wiring diagram provides additional information about the interactions between elements relating to activation and inhibition. Due to cost concerns, it is optimal to gain insight into biological networks with as few experiments and data as possible. Minimal wiring diagrams identify the …

Seed Longevity And Climatic Tolerance Of San Joaquin Wooly-Threads (Monolopia Congdonii; Asteraceae) An Endangered Plant From The San Joaquin Desert, California, Paul Excoffier

Master's Theses

San Joaquin wooly-threads (Monolopia congdonii; Asteraceae) is a federally-listed, endangered annual plant species from the desert areas of the San Joaquin Valley. Its limited range puts it at risk of extinction if the climate changes in such a way as to hinder its growth and reproduction. The primary aims of the study were to 1) determine how long-lived the seeds of the M. congdonii are, a key determinant of survival of desert annual plant populations through long droughts and 2) determine how severely hotter, drier conditions impact the ability of emerged plants to grow and reproduce. Secondarily, I …

Evaluating And Improving Domain-Specific Programming Education: A Case Study With Cal Poly Chemistry Courses, Will Fuchs

Master's Theses

Programming is a key skill in many domains outside computer science. When used judiciously, programming can empower people to accomplish what might be impossible or difficult with traditional methods. Unfortunately, students, especially non-CS majors, frequently have trouble while learning to program. This work reports on the challenges and opportunities faced by Physical Chemistry (PChem) students at Cal Poly, SLO as they learn to program in MATLAB. We assessed the PChem students through a multiple-choice concept inventory, as well as through “think-aloud” interviews. Additionally, we examined the students’ perceptions of and attitudes towards programming. We found that PChem students are adept …

Wildfire Risk Assessment Using Convolutional Neural Networks And Modis Climate Data, Sean F. Nesbit

Master's Theses

Wildfires burn millions of acres of land each year leading to the destruction of homes and wildland ecosystems while costing governments billions in funding. As climate change intensifies drought volatility across the Western United States, wildfires are likely to become increasingly severe. Wildfire risk assessment and hazard maps are currently employed by fire services, but can often be outdated. This paper introduces an image-based dataset using climate and wildfire data from NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS). The dataset consists of 32 climate and topographical layers captured across 0.1 deg by 0.1 deg tiled regions in California and Nevada between …

Distribution And Ecological Function Of Pacific Lamprey In The San Luis Obispo Creek Watershed, Parker Kalan

Master's Theses

Pacific lamprey (Entosphenus tridentatus) is an endemic species to coastal watersheds along the Pacific Rim in North America and Asia. The species' geographic distribution is retracting and has not been mapped precisely, and the ability for the species to provide ecosystem services, such as water filtration, for supporting watershed management has not been tested. The San Luis Obispo Creek watershed, California, USA is at the southern end of Pacific lamprey’s retracting distribution, and the San Luis Obispo watershed is impacted by degraded water quality, making investigation of Pacific lamprey in the San Luis Obispo Creek watershed of direct …

A Network Analysis Of Covid-19 In The United States, Joseph C. Mcguire

Master's Theses

Through methods in network theory and time-series analysis, we will analyze the spread of COVID-19 in the United States by determining trends in state-by-state daily cases through a network construction. Previous researchers have found frameworks for approximating the spread of the COVID-19 pandemic and identifying potential rises in cases by a network construction based on correlation of cases between regions [1]. Applying this network construction we determine how this network and its structure act as a predictor for overall COVID-19 cases in the United States by preforming a trend analysis on a variety of network statistics and US COVID-19 cases.

Specialized Named Entity Recognition For Breast Cancer Subtyping, Griffith Scheyer Hawblitzel

Master's Theses

The amount of data and analysis being published and archived in the biomedical research community is more than can feasibly be sifted through manually, which limits the information an individual or small group can synthesize and integrate into their own research. This presents an opportunity for using automated methods, including Natural Language Processing (NLP), to extract important information from text on various topics. Named Entity Recognition (NER), is one way to automate knowledge extraction of raw text. NER is defined as the task of identifying named entities from text using labels such as people, dates, locations, diseases, and proteins. There …

Effects Of Experimental Scale On The Adsorption Of Two Pharmaceutical Drugs Detected In Municipal Wastewater Effluent, Michael Moore

Master's Theses

Pharmaceutical drugs are being produced and consumed in increasing quantities every year and are poorly treated by conventional wastewater treatment processes, leading to increasing detection of such compounds in surface water, groundwater, and municipal drinking water. Soil aquifer treatment (SAT) is a promising method for treating these emerging compounds through combined adsorption and degradation of target compounds in soil. This thesis examines the consistency of results from typical studies like adsorption isotherms and soil columns utilized in analysis of SAT performance, across varying experimental scales. The adsorption behavior of two pharmaceuticals was investigated as a function of experimental scale and …

Understanding Rare Species In California: An Assessment Of Camatta Canyon Amole (Hooveria Purpurea Var. Reducta) And A Meta-Analysis Of California Rare Plants In Literature, Kieran N. Althaus

Master's Theses

California is currently in the midst of a biodiversity crisis. There are approximately 5,000 native species of plants in California, a quarter of which are considered rare. Determining threats to these rare plants is often times difficult. Despite California's botanical resources, we still know very little about much of California’s rare plants. San Luis Obispo County is home to 2,000 of California’s native plant taxa, one- third of which are rare or endemic to the county. These species are of great local and environmental concern.

In Chapter 1, we attempted to assess the impact of non native species on a …

The Influence Of Cultural Stigma On Perceptions Of Mental Illness, Rakshitha Mohankumar

Master's Theses

The stigma of mental illness can often lead to the afflicted individual not receiving the professional help they need and thereby worsening their condition, which has serious consequences both for themselves and their loved ones. Moreover, stigma surrounding mental illness varies from culture to culture. This research study highlighted the significance of studying stigma and long-term coping with a loved one’s mental health issues across cultures. Differences in perceptions of mental health based on the type of culture and (in)experience of growing up with someone who had mental health issues were tested. I predicted that there were main effects of …

Steric Effect On Benzyl Ether Olefines Under Sadmet Polymerization, Su Hu

Master's Theses

Acyclic diene metathesis (ADMET) polymerization, a type of olefin cross metathesis, is a step-growth and condensation polymerization that can be used to synthesize hydrocarbon polymers with diverse functional groups. Traditional ADMET with symmetric α,ω-dienes is not selective and can only form homopolymers or statistical copolymers. Changing to monomers with acrylate functional groups allows selective reactivity to form block and alternating polymers. In this project, we want to explore other functional groups that result in selective reactivity to form advanced polymer architectures via what we have termed selective acyclic diene metathesis (SADMET) polymerization. Developing new functionalized monomers for SADMET polymerization allows …

The Role Of Ions In Irradiated Astrophysical O2 Ice, Kristen J. Darnell

Master's Theses

Cosmic ices contain ions produced by irradiation from cosmic rays and UVphotons, yet solid-phase ion-ice reactions are currently ignored in all astrochemical models, even though gas-phase ion-molecule reactions are arguably the single-most important class of reactions in astrochemistry. Thus, developing a model that includes solid-phase ion-ice reactions is essential to accurately model interstellar ice chemistry, especially given the recent launch of the James Webb Space Telescope. To fill this gap, we have compiled a solid-phase chemical network for use in a rate-based irradiated ice astrochemical model which, for the first time, includes ionic species produced via the photoionization of the …

The Shallow Benthic Invertebrate Recovery From The End-Cretaceous Mass Extinction Across The Gulf Coastal Plain, Ronan B. Beltracchi

Master's Theses

The Gulf Coastal Plain, in the southeastern United States, contains several sites with well-preserved fossil assemblages from the Cretaceous- Paleogene boundary (K/Pg). Changes in benthic macroinvertebrate assemblages after mass extinction events commonly include reduction in body size of surviving organisms and preferential survival based on ecospace occupation. This study examines patterns of functional ecology and body size change in mollusk fossils from bulk samples collected throughout the post-extinction recovery interval at a well-studied boundary site from Darting Minnow Creek in Brazos, Texas USA and a recently described K/Pg boundary section on the Ouachita River in Malvern, Arkansas USA. The proportional …

Fragmentation Drives Dominant Plant Encroachment On A Horizontal Wastewater Treatment Levee, Joia S. Fishman

Master's Theses

Urban coastal wetlands protect humans from sea-level rise while providing valuable habitat for wildlife. Degradation and loss of these wetlands threaten urban infrastructure such as wastewater treatment facilities. Nature-based adaptive solutions with the combined purposes of bioremediation, coastal defense, and habitat creation are being tested to make communities safer and more resilient. The current research examines a 6-year-old experimental horizontal levee at the Oro Loma Sanitary District in San Lorenzo, California. Using horizontal transects and quadrat sampling, I compare the success of two planting strategies – a wet meadow and a riparian scrub community – on an ecotone slope. I …

The Influence Of Happiness On The Perception Of Ingroup And Outgroup Stereotypes, Diego R. Gómez

Master's Theses

An important social issue that influences judgments between ingroups and outgroups is how moods influence stereotype judgments. For instance, research on moods has provided evidence that happiness increases stereotype judgments. However, research has not considered the impact of individuals’ ingroup membership and how it may moderate these effects. The purpose of this study was to explore the potential moderating role that ingroup membership may have on the effects of happiness on stereotype judgments. University student participants in a happy or neutral induced mood completed a disciplinary task to assess guilt of either a Hispanic or non-Hispanic suspect of an assault …

The Spatial Distribution Of Mercury Contamination In The Yolo Bypass, California, Thomas S. Mykytyn

Master's Theses

Gold and mercury mining in the latter half of California’s 19th century resulted in massive and lingering alterations to downstream ecosystems through sedimentation and mercury contamination. Located at the confluence of Sierra Nevada and Coast Range watersheds, the Yolo Bypass is a critical conveyor of flood waters from the Lower Sacramento Valley to the Sacramento–San Joaquin Delta. Sedimentation in the bypass diminishes its flood conveyance capacity, and Hg contamination is hazardous to humans and ecosystems. The purpose of this study is to locate and quantify mercury contamination in the Yolo Bypass. Concentrations of total mercury ([THg]) were measured in 22 …

Inaccessible Interpolated Imagery: How Coffee Farmers In The State Of Chiapas Might Access Political Economic Opportunity Through Representation, Paolo Fiann Bicchieri

Master's Theses

Here is a useful parable to boil down the idea of this project and set the tone: when one goes to the bar to tell a story about a fight at the bar, they would never venture to place themselves as the hero of the brawl, taking out three drunkards in a single punch, unless they were really in the bar, at that time, fighting a good fight. One would never do this as the bartender, locals, and regulars would all know if this were the case or not. Yet transnational corporations, governments, and even consumers do this all the …

Reproductive Health In Rural Guatemala: Finding A Medium Between State And Ngo Policies, Zayra Rivera

Master's Theses

The purpose of this study is to understand and evaluate the manner in which the NGO sector surpasses state led efforts related to improving knowledge about reproductive health within rural areas in Guatemala. This research focuses on using methodologies from four Adolescent Youth Health Programs within the region of Lake Atitlan as well as state run institutions such as schools and health centers.

More specifically, this case study seeks to analyze the current gaps sexual and reproductive health programming in rural indigenous towns in the Sololá department of Guatemala. It compares four private NGO institutions with two public organizations, specifically …