Digital Commons Network^™

The Impacts And In-Depth Study Of The Environmental Contaminant, Perfluorooctane Sulfonic Acid, And Its Interactions With Water, Karla Veronica Salazar

Theses and Dissertations

Perfluorooctanesulfonic acid (PFOS), similar to perfluorooctanoic acid (PFOA), is a synthetic chemical that has been classified as a persistent organic pollutant (POP) by the Stockholm Convention since 2009. Due to the wide previous usage, high stability, high bio-accumulative, and low degradative properties is the reason that PFOS has been found in several compartments of the environment including ocean water, ground water, air, and sediments. Due to the strong interactions generated by the sulfonic acid end, this compound has a tendency to stay in the environment for long periods of time and has proved to be difficult in the removal from …

Positive Well-Being And Satisfaction With Life: Variables Affecting The Quality Of Life Of People With Bipolar Disorder, Maria Del Trevino-Zuniga

Theses and Dissertations

Bipolar disorder (BD) is a highly prevalent and severe mental illness of significant public health importance. Characteristics of BD include dramatic shifts in mood, energy, and activity levels affecting a person's ability to carry out day-to-day tasks. These shifts in mood and energy levels are more severe than everyone's regular ups and downs (Rihmer & Kiss, 2002). Managing BD is complex; and social and occupational life disruptions are well-documented, including higher divorce rates, unemployment, and suicide (Marrag et al., 2015). Research has consistently shown individuals with BD have a higher mortality rate compared with the general population (Walker et al., …

Home Range Dynamics And Juvenile Dispersal Of Gray Hawks In The Lower Rio Grande Valley, Michael Stewart

Theses and Dissertations

Using GPS-GSM transmitters I determined when 14 juvenile Gray Hawks (Buteo plagiatus) in the Lower Rio Grande Valley of Texas fledged from their natal areas and how far they traveled once they dispersed. These transmitters also allowed me to calculate home range sizes for 22 adults. Additionally, with the GPS-GSM transmitters and 15 VHF transmitters, I discovered that adult Gray Hawks in the study area remained in their territories year-round. Home range sizes were calculated using the minimum convex polygon estimator, the estimation of kernel home-range, and the estimation of kernel Brownian bridge home-range. The same three methods allowed me …

Morphological Characterization And Functional Assessment Of Trichomes In Solanaceae, Sakshi Watts

Theses and Dissertations

Chapter 1: This chapter provides an overview of various trichome types in plants, and also empirically examines their variation on abaxial and adaxial leaf surface of 14 Solanum species. Detailed nomenclature, density, and dimension measurements of each trichome type has been provided using scanning electron-microscopy.

Chapter 2: Scanning electron microscopy was major component of methodology used in my thesis for scanning leaf samples to estimate trichome traits. In this chapter, a more efficient and cost-effective methodology for scanning electron microscopy has been explored.

Chapter 3: This chapter examines the relationship of trichome density and herbivore feeding behavior using abaxial and …

Brevity Vs. Breadth: Can Memory Disorders Be Diagnosed Using Fewer Neuropsychological Assessments?, Analise Roccaforte

Theses and Dissertations

Object: The present study examines the clinical utility of combining a cognitive screener, Montreal Cognitive Assessment (MoCA), with a measure of adaptive functioning, Texas Functional Living Scale (TFLS), to diagnose memory disorders when differentiating between cognition within normal limits (WNL), mild cognitive impairment (MCI), and Alzheimer’s disease (AD). Method: A total of 207 Health First Memory Disorder Clinic patients, ages 64-94, were included in the study. Participants were screened using the MoCA and then they completed a brief neuropsychological evaluation, which included the TFLS. Participants were only included if they received a diagnosis of cognition WNL, MCI, or AD. They …

Utilizing The Radsm Process: Developing An Unobtrusive Measure Of Cohesion, Zachary Lee Rahner

Theses and Dissertations

In this study, verbal indicators produced following the RADSM process were used to code transcript data collected from 62 three-person teams playing a cooperative bridge crew simulator. A training dataset, consisting of 88 mission transcripts, and a testing dataset, consisting of 39 mission transcripts, were created from the data. Multilevel modeling was employed to develop a linear-regression algorithm to predict/measure team task and social cohesion. The findings revealed that task cohesion perceptions are linked to the proportion of speech dedicated to information requests and instructions, whereas social cohesion perceptions are associated with the proportion of speech dedicated to amusing and …

Autonomous Feature Detection For Capture Path Planning For Rendezvous And Docking With Non-Cooperative Spacecraft, Trupti Mahendrakar

Theses and Dissertations

With the increasing risk of collisions with space debris and the growing interest in on-orbit servicing, the ability to autonomously capture non-cooperative, tumbling target objects remains an unresolved challenge. This thesis provides an autonomous and artificial intelligence solution to either inspect, avoid, or perform on-orbit spacecraft servicing of an uncooperative resident space object (RSO). The solution is built on the fundamentals of Convolutional Neural Networks (CNN), which is used to classify the four most targeted features of a spacecraft essential for docking and collision avoidance during rendezvous, such as solar panels, antennas, spacecraft bodies, and thrusters. The solution was then …

Synthesis, Isolation And Structural Elucidation Of Cage-Shaped Aluminum And Gallium Phosphorous Aryloxide Complexes As Highly Reactive Lewis Acids And Carboxyboranes As Carbon Monoxide Releasing Molecules (Corms), Hussam Wannas Shinawa Alhamza

Theses and Dissertations

Group 13 Lewis acids have gained a lot of interest in over the years due to their reactivity, potency, and applications in the field of catalysis. Generally, there is a direct relationship between the catalytic activity of the organometallic Lewis acid and its acidity. However, this gives rise to a bigger challenge which is related to the stability of the catalyst. Our preliminary results from working on the catalytic reduction of CO2 have shown catalytic deactivation after one or two cycles. Utilizing bulkier substituents such as monodentate phenolates have shown promising increased stability and reactivity. The structural optimization (i.e., open-shape …

3d Printed Bioglass Incorporated Collagen Matrices For Musculoskeletal Tissue Engineering, Nilabh Sunil Kajave

Theses and Dissertations

Musculoskeletal injuries are a major cause of disability affecting millions of people around the world and resulting in a significant economic burden of over $14 billion. Surgical intervention using autografts and allografts is the current gold standard used in the clinic for the repair and regeneration of musculoskeletal injuries, but these treatment options are associated with major limitations such as donor-site morbidity, need for multiple surgeries, immune-related complications, and risk for disease transmission. Over the past three decades, the development and application of tissue engineering strategies for restoration and reconstruction of damaged or diseased musculoskeletal tissues have gained considerable momentum …

Charged Particle Environment Testing Of A Deep Space Radiation Shield With Associated Fabrication And Calibration Of Pulsed Power Systems, Mark Bedford Moffett

Theses and Dissertations

Space radiation is one of the primary dangers faced outside of the protective magnetosphere of Earth. Despite the persistent radiation threat to self-contained human habitation and the risk of increased exposure during long-duration missions, reliable long-term radiation protection is not well-developed. Active shielding is an avenue of preventative radiation protection that could be deployed to protect astronauts and biological life from the effects of radiation. This dissertation explores the design scalability of an active magnetic shield for protecting against isotropic radiation in deep space. Each shield is composed of two concentric, elliptical layers of circular conducting coils, each arranged like …

A Comparative Study On The Application Of Intelligent Algorithms As The Solution Of Inverse Heat Conduction Problems, Dominic Allard

Theses and Dissertations

A critical component necessary for the safety and survival of space vehicles are the thermal protection systems (TPS). Especially when subject to atmospheric re-entry, the heating loads subject to the space vehicle requires the implementation of extensive protection. The TPS commonly used currently are passive ablative materials which burn away under extreme heat flux. Due to the nature of the material and the incident heat flux, it is not feasible to attain accurate, real-time measurements for the boundary conditions with sensors placed on the surface of the space vehicle. The ability to do such would allow opportunities to implement active …

A Machine Learning-Based Approach To Predict And Optimize The Performance Of Zero Energy Building (Zeb): A Case Study For Florida, Benjamin Kubwimana

Theses and Dissertations

Machine learning is currently one of the most searched fields aiming to solve real-life problems. Building simulation software tools help engineers estimate building energy behaviors before the actual construction, allowing implementation of more energy efficient choices in building design and construction. Current building energy simulation software tools are mostly physics-based and still lack the benefit obtained with machine learningbased modeling, which offers fast and less computationally expensive techniques to build energy models and efficiently perform design optimization. This thesis presents a machine learning-based approach for building energy modeling and optimizing design parameters to minimize building’s energy consumption. The study is …

Changes In The Abundance And Distribution Of Benthic Mollusks In Polluted Sediments Of A Shallow Subtropical Estuary, Rachael Holtsberg Stark

Theses and Dissertations

The Indian River Lagoon (IRL) has been degraded by decades of eutrophication, and has accumulated an abundance of fine-grained, organic-rich sediments (muck). To quantify the impacts of organic sediments and environmental dredging, benthic mollusks were chosen to serve as bioindicators of environmental change, sediment health, and water quality. Data on species richness, biodiversity, and abundances was collected alongside sediment and water quality data before, during and after dredging. Organic sediment content was found to have an inverse logarithmic relationship benthic mollusk biodiversity, species richness, and abundance. Sediments low in percent organic content (0.7% to 6.1%) were located near the adjacent …

Variations In Otolith-Zinc Concentrations Of Brown Surgeonfish (Acanthurus Nigrofuscus) Between Marine Protected Areas And Fished Reefs, Matthew Austin Nichols

Theses and Dissertations

As human populations continue to increase, the growing reliance on exploited fish stocks has furthered patterns of declining body size and biomass worldwide. To mitigate these impacts, fisheries managers have implemented a variety of conservation strategies, including marine protected areas (MPA), as these serve as a refuge for fish, resulting in increases in numerous health metrics (fish density, biomass, body-size, and species diversity). By using fish otolith samples previously concluded to have physiological and morphometric differences between MPA and fished reef (FR) fish, this thesis explores the potential of using microchemical analysis of zinc (Zn) to reveal impacts MPAs might …

Development And Optimization Of A Denitrification System To Promote Biological Nutrient Removal In A Subtropical Estuary, Abigail Gering

Theses and Dissertations

Eutrophication impacts coastal ecosystems globally and triggers phytoplankton and algal blooms, leading to an increase in oxygen demand in the water column and sediments due to various biogeochemical processes. Naturally, biological nitrification, denitrification and anammox processes help to remove nitrogen predominately by nitrifying and denitrifying bacteria in the sediments. Eutrophic systems have increased nutrient and organic matter loading and are prone to the accumulation of ‘muddy’, fine-grained, organic-rich sediments (locally termed ‘muck’) that may not be able to support high enough populations of these bacteria, and therefore, may not adequately support nitrification/denitrification processes that would otherwise remove nitrogen. To decrease …

Factors That Influence The Extent To Which Cities On Florida’S Atlantic Coast Are Preparing For Climate Change: A Multiple Regression Analysis And Learning Opportunities For Policymakers, Sheila Ann Young

Theses and Dissertations

This study involved a survey (Appendix A) to leaders of 158 cities inside the counties that border the Atlantic coast of Florida. The impetus behind this study was to identify how policymakers were obtaining, understanding, and sharing information about climate change in order to help inform the policymaking process about adaptation. We cannot only train students at the secondary and university levels about climate change and expect policies to change right away. Those students, for the most part, will not be in policymaking leadership positions for years or decades. What is needed now are strategies to address the climate change …

The Effects Of A Flipped Classroom Compared To A Traditional Classroom On Students’ Mathematics Achievement And Critical Thinking Skills At Benghazi University, Tarik O. Hamed Beltaib

Theses and Dissertations

This study aimed to compare the effects of two different instructional models (flipped and traditional) on students’ mathematics achievement and critical thinking skills (CTS) at Benghazi University. This study used a quasi-experimental non-equivalent control group design involving intact classes of 80 students. The primary dependent variables were mathematics achievement and critical thinking skills, and the primary independent variable was the instructional methods. The data collection instruments consisted of several different assessments:(1) A pre-and post-test (Placement test and Final test) designed by the mathematics department (2) the California Critical Thinking Skills Test (CCTST) was administered at the beginning and end of …

Development Of A Magnetic Confinement Attachment For Enhanced Signal In Handheld Laser Induced Breakdown Spectroscopy Soil Analysis, Alfred C. Anderson

Theses and Dissertations

Field techniques for characterizing low levels of heavy elements of less than 100 parts per million in soils tend to be unreliable because of the relatively weak signal of these elements and the large, variable background inherent to analyzing soils with minimal sample preparation. To enhance the detection and analysis capability of a handheld laser-induced breakdown spectroscopy (LIBS) instrument, this work investigates the effects of a unique magnetic confinement apparatus on signal intensities, focusing on five iron lines as well as those from actinides in 11 soil samples. The proposed magnetic confinement apparatus achieved over 0.8 T but did not …

The Relationship Between Mindfulness, Social Anxiety Traits, And Emotions, Maria Jackeline Diaz

Theses and Dissertations

The relationship between mindfulness, social anxiety traits, and emotion processing is the first study of its kind to be looked over. In this study we will assess similarities and differences, plus how they work together to provide further research and understanding of these complexities when combined. Such research can be helpful in making us understand our emotions, as well as how our emotions can be perceived in social functioning and communication.

Assessment And Monitoring Of Deltaic Wetlands And Fluvial Systems: Refining And Validating A Multimetric Index Of Resaca Ecosystem Health, David Lecusay Jr.

Theses and Dissertations

Resacas are ancient distributary channels of the lower Rio Grande River historically serving as floodwater drainage pathways onto the Laguna Madre, Texas. Resacas provide numerous ecosystem services and critical habitat for many species. Mainly influenced by urbanization, integrating a multimetric index for assessing and monitoring resaca ecosystem health is required for adaptive management. The Resaca Health Index (RHI) integrates structural and functional components: (1) nonredundant metrics describing fish communities (Fish Community Index); (2) Trophic State Index derived from Secchi depth; (3) decay constant from riparian vegetation leaf litter decomposing in the water column; and (4) a riparian quality index based …

Total Synthesis Of E Stereoisomers Of Bilirubin Oxidation Products, Tess C. Ruiz

Theses and Dissertations

The purpose of the research was to synthesize the E stereoisomer of Bilirubin Oxidation Products that had not been synthesized through a total organic synthesis at the start of this project. There were numerous different procedures for the bromination of citraconic anhydride performed in an attempt to optimize yield and purity. A proposed scheme for the total synthesis of the E isomers was constantly updated and altered while the project was ongoing. The bioactivity of the compounds was to be tested if the project had been finished. This might have contributed to a greater understanding of their function and association …

Resiliency Of Utah's Road Network: A Logit-Based Approach, Max Evan Barnes

Theses and Dissertations

The Utah Department of Transportation (UDOT) manages and maintains a complex state-wide network of highways. Recent incidents such as the collapse of the I-35W bridge in Min- neapolis, Minnesota, and the I-85/Piedmont Road fire and subsequent bridge collapse in Atlanta, Georgia, have brought identification of transportation network vulnerabilities to the forefront of UDOT’s planning efforts. Traditional estimates of transportation network impacts have focused on increases to user travel time or the volume of affected traffic, but studies of these disasters have revealed that when facing a degraded transportation network, people adjust their trip making in terms of destination, mode, and …

Role Of Hsp70 And The Tlr4-Md2 Complex In The Vasculature: From Function To Dysfunction In Diabetes, Amanda Almeida De Oliveira

Theses and Dissertations

Diabetes impairs vascular functionality, which contributes to the pathophysiology of its associated complications. Recently, it was suggested that innate immune receptors assist in the development of diabetic vasculopathies, which sustains the pro-inflammatory state of the disease. Among these receptors, Toll-like receptor 4 (TLR4) is a strategic player as its activation prime the release of inflammatory mediators and reactive oxygen species (ROS), which are well-known pathological mechanisms linked to diabetic complications. The TLR4-Myeloid differentiation factor 2 (MD2) complex has gained much attention over the last decade, primarily because it interacts with self-produced molecules. In vascular tissues, the Heat-shock protein 70 (HSP70) …

Discussion Boards In The Online Classroom: Are They Actually Influencing Instructor Mediated Immediacy, Student Motivation, Student Affective Learning, Student Connectedness, And Online Learning Climate?, Samantha Lynn Schultz

Theses and Dissertations

Discussion boards are one of the most popular forms of asynchronous discussion in online classes. Utilized by instructors in asynchronous and synchronous courses to facilitate class discussions, they offer a means for the class to communicate among each other and with the instructor. Few researchers have examined how the use of discussion boards in the online classroom affects instructor mediated immediacy, student motivation, affective learning, connectedness, and the online learning climate. This study sought to examine the influence of discussion boards on these variables. After review of research on discussion boards and related variables, participants completed a questionnaire composed of …

Phylogenetic Relationships Of Genera In The Caddisfly Family Limnephilidae Using Anchored Hybrid Enrichment-Based Phylogenomic Analysis (Insecta:Trichoptera), Kyle Charles Rawlinson

Theses and Dissertations

Limnephilidae is a large family within Trichoptera, consisting of 4 subfamilies (Dicosmoecinae, Ecclisomyiinae, Limnephilinae, and Philocascinae), 98 genera, and 1178 species. It is among the most diverse families within Trichoptera. It is also ecologically diverse, occupying more habitats than any other family in the order. There are currently no published generic phylogenies of Limnephilidae based on molecular data. Here we used anchored hybrid enrichment to capture and sequence 922 loci for 57 species taken from what have been considered the full range of genera in the family. We expanded the taxon sampling by adding supplementary species with DNA barcodes, 28S …

Exploring Middle School Students’ Strategies When Solving Surface Area Tasks, Pamela Sue Beck

Theses and Dissertations

Measurement is an important concept in school mathematics (Clements, 2003). There are several studies and empirical evidence on students’ thinking about geometrical measurement of length, area, and volume (e.g., Barrett et al., 2017; Battista, 2007, 2012; Eames, 2014; Lehrer, Jenkins, & Osana, 1998; Miller, 2013; Outhred & Mitchelmore, 2000; Sarama & Clements, 2009); however, there is limited research on students’ thinking about surface area measurement. This study addresses a gap in the literature with empirical evidence of students’ thinking about surface area measurement. This study also aimed to examine students’ responses to tasks involving surface area measurement and categorize the …

A Study In Soft Robotics: Metrics, Models, Control, And Estimation, Levi Thomas Rupert

Theses and Dissertations

Traditional robots, while capable of being efficient and effective for the task they were designed, are dangerous when operating in unmodeled environments or around humans. The field of soft robotics attempts to increase the safety of robots thus enabling them to operate in environments where traditional robots should not operate. Because of this, soft robots were developed with different goals in mind than traditional robots and as such the traditional metrics used to evaluate standard robots are not effective for evaluating soft robots. New metrics need to be developed for soft robots so that effective comparison and evaluations can be …

Best Friends Forever And Family Ties: Continuity And Change In Closeness With Parents And Friends Among Australian Adolescents, Mckell A. Jorgensen-Wells

Theses and Dissertations

During adolescence, the need for social connection increases. Yet, fostering emotional closeness in relationships becomes more complex, as the need for autonomy also increases and social environments must adapt to become conducive to these seemingly competing needs. This complexity necessitates more research on what happens to close relationships during adolescence, so parents, scholars, and practitioners are better equipped to help individuals navigate the unique social atmosphere of adolescence. The current study draws upon multi-level modeling techniques to estimate growth models of Australian adolescents' closeness to parents and closeness to friends from ages 12-17 and examine predictors of these trajectories. Findings …

Trichloroethylene Remediation By Engineered Soil Bacteria, Madeline Hannah Mclaughlin Armond

Theses and Dissertations

Trichloroethylene (TCE) is a toxic pollutant that has become a widespread problem by seeping into groundwater across the developed world. Clean-up of sites contaminated with TCE is extremely difficult due to the absence of an efficient and cost-effective method for clean-up. Bioremediation efforts include a variety of potential microbial candidates with various metabolic capabilities as clean up options of contaminated sites. Cupriavidus necator, a soil bacterium was found to possess the ability to degrade TCE via a phenol-dependent pathway. Previous research by Ayoubi and Harker (1998) created a strain (MM02) capable of constitutive TCE degradation but the underlying genetic alteration …

Investigating The Role And Localization Of B Cells In The Red-Eared Slider, Trachemys Scripta, Whitney Hurst

Theses and Dissertations

The immune system of humans has been studied extensively, but very little is known about the immune response in reptiles. Our lab has been working to better understand the immune system of a pond turtle, Trachemys scripta (red-eared slider). Turtles are known for their longevity and their immune system should play an important role in their ability to survive. Our main interest is understanding B cell function and location in slider turtles. B cells are a type of white blood cell that play a vital role in the immune response of humans, with the majority secreting antibodies that mark invading …