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Contribution Of Submarine Groundwater Discharge To Select Biogeochemical Fluxes In St. Louis Bay, Mississippi, Haley Spaid

Master's Theses

This thesis assesses the role of submarine groundwater discharge (SGD) in St. Louis Bay, Mississippi. Located along the northern Gulf of Mexico, St. Louis Bay (SLB) is a semi-enclosed bay that is important to the local area for recreation and tourism. SGD is the movement of any water into the water column across the sediment-water interface. In coastal environments, SGD can be a source of a variety of substances including nutrients and pollutants. In this study, a steady state mass balance approach was used to quantify SGD flux for SLB using ²²³Ra, ²²⁴Ra, and Ba. Using the water …

Assessment Of Genetic Diversity In Largetooth Sawfish, Pristis Pristis, Populations Over The 20th Century, Ann Fearing

Master's Theses

The Critically Endangered Largetooth Sawfish, Pristis pristis, experienced global declines in range and abundance over the past century and Australia is now their last stronghold. This research aimed to understand whether these declines have been accompanied by a reduction in levels of genetic diversity. Using P. pristis tissue samples sourced from natural history specimens, three fragments (616-bp, 386-bp, 141-bp) in the mitochondrial DNA (mtDNA) control region were PCR-amplified. At each fragment, significant genetic structure was found in P. pristis overall (Φ_ST=0.946, N=9; 0.813, N=54; 0.771, N=99). The Indo-West Pacific and Atlantic/Eastern Pacific each harbor genetically distinct lineages of …

Predicting Personality Type From Writing Style, Tanay Gottigundala

Master's Theses

The study of personality types gained traction in the early 20th century, when Carl Jung's theory of psychological types attempted to categorize individual differences into the first modern personality typology. Iterating on Jung's theories, the Myers-Briggs Type Indicator (MBTI) tried to categorize each individual into one of sixteen types, with the theory that an individual's personality type manifests in virtually all aspects of their life. This study explores the relationship between an individual's MBTI type and various aspects of their writing style. Using a MBTI-labeled dataset of user posts on a personality forum, three ensemble classifiers were created to predict …

Hate Speech, Habitus, And Identity Signaling On 4chan’S Politically Incorrect Board, Jonathon Geiger

Master's Theses

Websites, such as 4chan, have provided a place for extremism and hate speech to flourish through anonymous discourse. One group that has been especially important to this growth has been the alt-right. The alt-right is a far-right white nationalist movement that is known for engaging in trolling, creating memes, and generating conspiracy theories. Past research has focused on the amounts of hate speech and characterizing content on the website. However, past studies have not looked at the experience of using the website through the combination of participant observation and content analysis. Here I show that the extensive use of hate …

Microplastic Abundance, Distribution And Impacts On Sargassum-Associated Juvenile Fishes In The Gulf Of Mexico, Olivia Lestrade

Master's Theses

Microplastics are a concern in marine environments because they are highly durable, ubiquitous, and can be mistaken for food and ingested by small organisms. Pelagic Sargassum, an important habitat for larval and juvenile stages of many fish species, is found in large surface aggregations, and may provide complex structure in which microplastics become trapped. This could lead to greater risk of microplastic ingestion by fish early life stages associated with Sargassum habitats. To better understand the impacts of microplastics within Sargassum communities, this study examined 1) microplastic concentrations and ingestion by juvenile fishes associated with Sargassum; 2) the microbial …

Determining The Trophic Role Of Red Snapper (Lutjanus Campechanus) In Mississippi State Waters Using Stomach Content And Stable Isotope Analysis, Branden Kohler

Master's Theses

The goal of this study was to determine the diet composition, trophic position and ecological role of red snapper (Lutjanus campechanus) in Mississippi state waters utilizing stable isotopes (δ¹³C and δ¹⁵N) and stomach content analysis. Stable isotope analysis of fish and their prey can provide information on species-specific basal resource utilization, diet composition and trophic position which can improve food web models and inform fisheries management decisions. Particulate organic matter (POM), the presumed base of the food web, red snapper muscle tissue, and red snapper stomach contents were collected from 25 sites in 2016 and …

Development And Use Of An Environmental Dna Tool To Monitor Recovery Of The Critically Endangered Smalltooth Sawfish, Pristis Pectinata, In The Northwest Atlantic, Ryan N. Lehman

Master's Theses

The Critically Endangered Smalltooth Sawfish, Pristis pectinata, was once common in the tropical and subtropical waters of the Atlantic Ocean; however, following global declines in range and abundance over the past century, individuals were restricted to the waters of south and southwest Florida (SWFL) by about the 1980’s. Recently, public encounter reports have emerged in historically occupied habitats in United States waters, suggesting individuals are present in, or re-occupying, these areas, although the status of P. pectinata outside of SWFL is not currently well understood. Targeted environmental DNA (eDNA) surveys were chosen to assess the occurrence of P …

Exploring Dissociation As A Facilitator Of Suicide Risk Using Virtual Reality, Nicole Caulfield

Master's Theses

Research shows that suicidal behavior is not a result of a single cause or single event, but instead is an interaction of facilitators. One potential facilitator that needs further exploration is dissociation. Dissociation has been consistently linked to suicidal behavior, and treatment for dissociative disorders seem to be associated with a reduction of suicidal ideation and suicide attempts. Prior theories have posited that dissociation increases the possibility of a suicidal act because of intensified disconnect from the body. However, these theories do not indicate whether dissociation is a facilitator of suicide risk by increasing suicidal ideation, attempt behaviors, and capability …

Telescope Parallel Actuator Mount: Control And Testing, Samuel S. Artho-Bentz

Master's Theses

This thesis approaches the task of designing a control system for the Parallel Actuator Mount developed by Dr. John Ridgely and Mr. Garrett Gudgel. It aims to create a base framework that directly controls the telescope and can be expanded to accept external command. It incorporates lower priced components and develops more easily approachable software with great functionality. An open-loop method for velocity control is established. Developing repeatable tests is a major focus. Testing finds the control methods developed result in velocity error of less than 5% and position error of less than 1.5% despite several mechanical issues and inaccuracies. …

Lc-Ms/Ms Method Development For The Quantitation Of Methylmalonic Acid Using Aqueous Normal Phase Chromatography, Daniel Joseph Biocini

Master's Theses

The aim of the study was to develop a quantitative assay for methylmalonic acid (MMA), an important biomarker for clinical diagnosis of vitamin B12 (B12) deficiency. The techniques of liquid chromatography and tandem mass spectrometry (LC-MS/MS) are used for separation and quantitation of MMA, as well as its endogenous isomer succinic acid. The MS/MS method was developed using an infusion set-up and manual tuning experiments. Relevant transitions were detected for the two analytes and MMA-d3, then a preliminary MS/MS method was developed. The preliminary LC method was further optimized. Various gradients, mobile phases (MPs), and additive combinations were used across …

The Relationship Between Authentic Leadership And Organizational Change Readiness: The Mediating Role Of Psychological Safety, Paulina Christine Manzano

Master's Theses

The purpose of the current study was to examine the mediating effect of psychological safety on the relationship between authentic leadership and organizational change readiness in the workplace. A total of 107 employees participated in the study, which utilized online survey distribution. Results showed that psychological safety partially mediated the relationship between authentic leadership and organizational change readiness. In other words, the more employees perceived their leadership to be authentic, the more likely employees felt safe taking risks at work, which in turn, increased employees’ emotional and cognitive inclination to adopt and embrace organizational change. Based on these findings, organizations …

Easy In Any Language: Syntax, Semantics, And Pragmatics Of Activity-Oriented Adjectives In Six Languages, David Koffman

Master's Theses

Words that denote the degree of effort required for some activity, called easy adjectives here, have distinctive behavior. This behavior is explored in six languages to determine how the semantics of these words is reflected in the expressions to which they can apply, the constructions in which they appear, and their use in discourse. For four Indo-European languages, English, Spanish, German, and Russian, the analysis is based on random samples from linguistic corpora. For two non-Indo-European languages, Japanese and Swahili, the analysis is based on consultant elicitations and published examples. The analysis confirms that easy adjectives have distinctive behavior compared …

The Moderating Role Of Agreeableness And Conscientiousness On The Relationships Between Burnout And Withdrawal Behaviors, Nikoo Samee

Master's Theses

It has been shown that employees who experience burnout are more likely to engage in withdrawal behaviors, which are behaviors that harm the morale of employees and the bottom line of an organization. There has been some research on the moderating effect of situational variables (e.g., leadership style) on the relationship between burnout and withdrawal behaviors, but there is a lack of research on how personal characteristics may play a role in such relationships. The purpose of this study was to examine the moderating role of agreeableness and conscientiousness on the relationship between burnout and three withdrawal behaviors: lateness, absenteeism, …

Effects Of Urbanization And Habitat On The Diet And Reproduction Of Red-Shouldered Hawks In Central California, Catherine Y. Fisher

Master's Theses

Urbanization alters biological community interactions and trophic structures compared to natural habitats; these changes may be reflected in the diets of apex predators such as raptors. The red-shouldered hawk (Buteo lineatus) is a dietary generalist that is expanding from natural and rural habitats into urbanized areas. In this study, direct observation was used to quantify the diet and reproductive success of red-shouldered hawks in Santa Clara County, California during the 2019 breeding season. GIS methods were used to quantify the nesting habitat and level of urbanization at each nest. Hawk diet consisted of mammals (50.4% by frequency and 77.7% by …

The Relationship Between Diversity Climate Perceptions And Organizational Citizenship Behavior And Work Engagement: The Mediating Role Of Overall Organizational Justice, Arika Nakajima Higgins

Master's Theses

Employees’ perceptions concerning their organization’s diversity climate have important implications for both the organization and the individual. Diversity climate research has traditionally focused on exploring the moderators of the relationship between diversity climate perceptions and the attitudinal outcomes of employees; however, research has neglected to examine behavioral outcomes and the potential mediators of the relationship. Therefore, the present study explored the indirect effects of overall organizational justice on the relationship between diversity climate perceptions and organizational citizenship behavior and work engagement. It was hypothesized that diversity climate perceptions would be positively related to organizational citizenship behavior and work engagement. It …

Optimal Parameter Values For Accurate And Repeatable Nanoindentation Of Human Trabecular Bone, Stephen Matthew Kmak

Master's Theses

Nanoindentation techniques have not been standardized for use on bone tissues, making comparison of bone material properties obtained via nanoindentation across studies difficult and unreliable. This study determined a set of optimal parameter values for thermal drift correction time, dwell time, and loading rate that can be used to obtain accurate and repeatable material properties from human femoral trabecular bone through experimentation and statistical analysis. All testing was conducted using a single nanoindenter on a single trabeculae, with the assumption that material properties within the individual trabeculae were internally consistent. Parameters not of interest during this study, such as ambient …

Implementation Of An Open-Source Digital Image Correlation Software For Structural Testing, Nicole V. Buck

Master's Theses

This thesis investigates the appropriateness of a simplified, open-source digital image correlation (DIC) software for use in quasi-static, structural testing utilizing two-dimensional (2D) DIC measurements. DIC is a non-contact optical measurement technique that uses computer vision to track unique attributes on the surface of an object. For structural testing, traditional instrumentation such as displacement sensors and strain gages are impractical for full field measurements due their limited ability to capture large amounts of data. However, over the past decade, DIC has proven a successful method for full-field kinematics measurements, making it an appealing tool for collecting high densities of accurate …

Exploration And Comparison Of Image-Based Techniques For Strawberry Detection, Yongxin Liu

Master's Theses

Strawberry is an important cash crop in California, and its supply accounts for 80% of the US market [2]. However, in current practice, strawberries are picked manually, which is very labor-intensive and time-consuming. In addition, the farmers need to hire an appropriate number of laborers to harvest the berries based on the estimated volume. When overestimating the yield, it will cause a waste of human resources, while underestimating the yield will cause the loss of the strawberry harvest [3]. Therefore, accurately estimating harvest volume in the field is important to farmers. This paper focuses on an image-based solution to detect …

A Water Balance And Sediment Yield Analysis Model For The Lopez Lake Reservoir, Lee Joon Faraca

Master's Theses

Lopez Lake Reservoir is the primary source of potable water for the Cities of Arroyo Grande, Grover Beach, Pismo Beach, and to the Community Service Districts of Oceano and Avila Beach. In this study, a water balance and sediment yield analysis model was developed for the reservoir’s watershed. The model was used to estimate evaporation from the lake and to examine the effects of a wildfire on the reservoir. Evaporation and wildfire are dependent on variables that change on a spatial and temporal scale, making modeling challenging. The County of San Luis Obispo uses pan coefficients to estimate evapotranspiration losses …

Rheological Studies Of Fully-Formulated Coatings Thickened With Heur: Effects Of Surfactants, Brandon M. Bonilla

Master's Theses

Rheology modifiers such as hydrophobically-modified ethoxylated urethane (HEUR)thickeners are included in waterborne latex coatings to optimize shear-rate dependent viscosity and other rheological properties. While these HEUR polymers are commonly used in industry, the complex chemical interactions that contribute to rheological properties are still not completely understood. Prior work in this area has focused on understanding latex-HEUR and latex-surfactant-HEUR interactions that affect rheological properties. Additionally, studies have been previously conducted to understand the relaxation mechanisms of complex interactions present in HEUR-thickened waterborne latex coatings under various dynamic conditions. The objective of this work is to extend the experimental work to fully-formulated …

Using Machine Learning To Predict Sag And Leveling Behavior Of Interior Architectural Paints, Ethan Kim

Master's Theses

In the world of interior architectural paints, rheology, or the deformation and flow of a fluid, is one of the largest economic and development hurdles for paint formulators. To achieve maximum functionality, coverage, and economy of product, the rheology of the coating must be properly optimized, balancing performance while minimizing undesirable flow defects such as paint sagging or visible brush and roller marks; these visual imperfections are associated with the sag and leveling properties of the paint. Many researchers have attempted to develop a better understanding of sag and leveling, either by drawing correlations or through mathematical derivation; however, neither …

High Pressure Combustor Flame And Wall Conjugate Radiative Heat Transfer, Andressa Johnson

Master's Theses

Efficient aeronautical engines operate at higher pressure ratios and temperature, creating challenges due to higher heat loads. Thermal radiation in aviation has conventionally been treated as correction factors or scaled from experimental data. The complexity of the radiative transfer equation (RTE) leads to computational costly solutions resulting in simplified treatment. The goal of this work is to extend knowledge of non-gray gas radiation modeling to gas-turbine combustor simulations under high-pressure conditions. A one-dimensional temperature solver for combustor liners with thermal barrier coating is developed first, and a non-gray wide-band spectral model for high-pressure conditions is constructed subsequently. Both retrieve spectral …

Galilean Invariance In Large-Eddy Simulation Of Shallow Convection, Oumaima Lamaakel

Master's Theses

In large-eddy simulations (LES) a computational-domain translation velocity can be used to improve performance by allowing longer time-step intervals. The continuous equations are Galilean invariant, however, standard finite-difference-based discretizations are not discretely invariant with the error being proportional to the product of the local translation velocity and the truncation error. Even though such numerical errors are expected to be small, it is shown that in LES of buoyant convection the turbulent large-scale flow organization can modulate and amplify the error. Galilean invariance of global flow statistics is observed in well-resolved direct numerical simulations (DNS). In LES of single-phase convection under …

Human Intention Inference Using Fusion Of Gaze And Motion Information, Daniel Trombetta

Master's Theses

Enabling robots with the ability to quickly and accurately determine the intention of their human counterparts is a very important problem in Human-Robot Collaboration (HRC). The focus of this work is to provide a framework wherein multiple modalities of information, available to the robot through different sensors, are fused to estimate a human's action intent. In this thesis, two human intention estimation schemes are presented. In both cases, human intention is defined as a motion profile associated with a single goal location. The first scheme presents the first human intention estimator to fuse information from pupil tracking data as well …

Alcohol-Related Consequences: Factor Structure And Associations With Trait Mindfulness And Drinking Motivations, Lauren Carney

Master's Theses

Objective. This two-study project aimed to determine if motivations to use alcohol (coping and social motivations) mediate the relationship between trait mindfulness and a variety of alcohol-related consequences and to determine if the relationship between motivations to use alcohol and alcohol-related consequences is moderated by alcohol use. Study 1 determined the factor structure of positive and negative consequences of alcohol use. In Study 2, this structure served as the outcome across eight moderated mediation models. Method. For Study 1, data were obtained from 165 undergraduate students to perform exploratory factor analysis (EFA) on alcohol-related consequences. For Study 2, …

Snap Assistance, Food Purchasing Behaviors And Dietary Patterns Among Overweight/Obese, Pregnant, Low-Income Latinas, Marta Holovatska

Master's Theses

No abstract provided.

The Role Of Beta-Hydroxybutyrate Supplementation In A Drosophila Model Of Traumatic Brain Injury, Derek Lee

Master's Theses

No abstract provided.

Cloud Cover And Pv Intermittence: Monitoring, Forecasting And Its Economical Value, Aaron Haegele

Master's Theses

The use of all-sky cameras and ancillary sensor equipment to monitor and to adjust fine resolution short range predictions of cloud cover offers an opportunity to develop efficient energy management systems. Solar photovoltaic (PV) energy is a variable renewable energy resource since solar irradiance is highly sensitive to the intermittent nature of cloud cover. Thus, tracking and characterizing clouds passing over PV areas is a critical factor when predicting the available energy of solar sources at any given time. Capital and operational costs associated with solar PV implementation are affected when inaccurate predictions are carried out. This research uses a …

Electrostatic Denaturation Of Dna-Cisplatin Adducts, Eddie Madrigal

Master's Theses

In this thesis, electrochemical approaches are used to determine the properties of deoxyribonucleic acid (DNA) by electrostatic denaturation. The electrochemical routine involves an application of a destabilization potential, an equilibration potential, and a square wave voltammogram (SWV) to monitor the extent of melting. Our method uses a monolayer consisting of thiol modified DNA and mercaptohexanol on a gold electrode. These electrodes are then incubated in a complementary sequence tagged with methylene blue. By using our electrostatic denaturation technique, different parameters are explored, such as surface densities, surface coverages, and ionic strengths. As proof of concept, these techniques were applied toward …

Motivation And Social Withdrawal In Schizophrenia: Factors Related To Passive Social Withdrawal And Active Social Avoidance, Emily Anne Peters

Master's Theses

Schizophrenia is a disabling disorder and social withdrawal in schizophrenia is related to particularly adverse outcomes. Social withdrawal may be a result of “passive” motivation (disinterest or lack of drive to engage with others) or “active” motivation (fear, hostility, or distrust of others). The purpose of this study was to better understand passive social withdrawal and active social avoidance, by exploring their relationships with social abilities and social functioning outcomes. In addition, we explored whether the EEG frontal alpha asymmetry hypothesis, which has been previously linked to shyness and sociability, might contribute to our understanding of social withdrawal motivation.

This …