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Revisiting Darwin’S Little Pond As A Method To Liberate Phosphorus From Apatite Under Prebiotic Hadean Earth Conditions, Jennifer Lago

USF Tampa Graduate Theses and Dissertations

Phosphorus is an essential element for life as we know it. Phosphorus, mainly in the form of phosphate, is key to biologic functions such as genetic material, energy production, and cellular framework. As phosphorus is key to so many important biological functions it is of no wonder the question of how phosphorus was incorporated into life initially is a fundamental question in how life began.

During this time a prebiotic phosphorus source would need to have originated in rock, as phosphorus has not volatile source on Earth. The most prevalent mineral source on a prebiotic Earth would likely have been …

Efficient Management Of Nitrogen And Phosphorus At Centralized Water Reclamation Facilities, Helene Kassouf

USF Tampa Graduate Theses and Dissertations

A variety of process configurations are employed at municipal water reclamation facilities (WRFs), such as 5-stage Bardenpho, oxidation ditch, modified Ludzack-Ettinger (MLE) process, and sidestream recycle. However, all of these configurations face certain challenges in achieving optimum treatment of nitrogen and phosphorus. In this dissertation, the driving objectives were to: (1) quantitatively assess the fate of nitrogen and phosphorus (mass fluxes) at a treatment facility that employs biological nutrient removal, aerobic digestion, and sidestream recycle, (2) evaluate the performance of a microbial fuel cell (MFC) as a technology to remove nitrogen from sidestreams at a treatment plant that employs that …

Fighting Mass Diffusion Of Fake News On Social Media, Abdallah Musmar

USF Tampa Graduate Theses and Dissertations

Fake news has been considered one of the most challenging problems in the last few years. The effects of spreading fake news over social media platforms are widely observed across the globe as the depth and velocity of fake news reach far more than real news (Vosoughi et al., 2018). The plan for the following dissertation is to investigate the mass spread of fake news across social media and propose a framework to fight the spread of fake news by mixing preventive methods that could hinder the overall percentage of fake news sharing. We plan to create a study on …

The Role Of Cpeb2 Alternative Splicing In Tnbc Metastasis, Shaun C. Stevens

USF Tampa Graduate Theses and Dissertations

Breast cancer is the second leading cause of cancer-related deaths for women in the U.S. Although the overall 5-year survival rate for breast cancer is 90%, this rate drops substantially for triple-negative breast cancer (TNBC) due to its high metastatic potential. Furthermore, there is a lack of targeted therapeutics for TNBC, and clinical trials have been largely unsuccessful. These characteristics validate the need for identifying novel therapeutic targets for the treatment of TNBC. The study of alternative splicing (AS) has emerged as a powerful tool to elucidate the molecular underpinnings driving cancer.

Our lab has identified cytoplasmic polyadenylation element-binding protein …

Understanding Nonprofit Boards: An Exploratory Study Of The Governance Practices Of Regional Nonprofits, Susan Ryan Goodman

USF Tampa Graduate Theses and Dissertations

Many researchers have catalogued best practices of board governance. Most of the existing research employed surveys to review compliance with these practices, and the results are highly quantitative as well as self-reported. This study used interviews of board members representing a cross-section of nonprofits to examine conformity with recommended governance best practices and procedures as well as to provide insight into how these practices have changed during their tenure.Semi-structured interviews were conducted with 18 nonprofit board members in the Tampa Bay area. Using the thematic coding approach proposed by Braun and Clark (2006), four themes emerged from the data: Recruiting, …

Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin

USF Tampa Graduate Theses and Dissertations

Currently, a significant challenge with reverse osmosis-based desalination is reducing the energy consumption and environmental impacts of the process. This project analyzed the viability of using pressure-retarded osmosis (PRO) for energy recovery in seawater desalination facilities using brine concentrate (the draw solution) and other water sources (the feed solution) such as wastewater effluent. The primary goal of this project is to decrease the cost and overall energy consumption of seawater desalination through PRO-based energy recovery. Process modeling, statistical and sensitivity analysis, energy and cost analysis, geospatial and GIS analysis, laboratory-scale testing, water quality analysis, SEM-EDS microscopy, computational fluid dynamics (CFD), …

Resolution Of Lava Tubes With Ground Penetrating Radar, Sanaz Esmaeili

USF Tampa Graduate Theses and Dissertations

Finding habitable places to keep astronauts safe from surface radiation, magnetic storms, and temperature fluctuations will be an important component of future planetary exploration missions. Remote sensing surveys on other planets indicate the presence of lava tubes. Ground Penetrating Radar (GPR) has shown great potential for detection of tunnels in terrestrial environments. In this research, the capabilities of this near surface rapid exploratory tool for detection of lava tubes are investigated. This dissertation describes terrestrial examples of how GPR can be utilized to explore tubes and addresses the capabilities of GPR for resolving tube-related features such as the floor, fractures, …

Oppression, Resistance, And Empowerment: The Power Dynamics Of Naming And Un-Naming In African American Literature, 1794 To 2019, Melissa "Maggie" Romigh

USF Tampa Graduate Theses and Dissertations

Oppression, Resistance, and Empowerment: The Power Dynamics of Naming and Un-naming in African American Literature, 1794 to 2019 researches and discusses the way African American authors both discuss naming and un-naming in their works and the way they use naming in their works to illustrate the dynamics of power in relationships—racial, familial, gender-related, work-related, etc. Chapter 1 focuses on the earliest forms of African American literature, memoirs in particular, also known as “slave narratives.” In their memoirs, many of those men and women who were formerly enslaved wrote about having their names taken from them and replaced with names chosen …

Engagement And Meaningfulness As Determinants Of Employee Retention: A Longitudinal Case Study, Calvin Williams

USF Tampa Graduate Theses and Dissertations

The lack of financial resources has long challenged government institutions to move employee wages toward the market rate average for hourly and salaried positions. This area of public employment, where motivation other than a pay increase is necessary due to constrained budgets, is not well studied or understood. The primary purpose of this longitudinal case study is to investigate factors that influence Administrative Service employees and increase their level of retention at the University of South Florida (USF), a state funded university. The objective of the case study was to better understand how enhanced psychological meaningfulness, and increased employee engagement …

Shortcut Nitrogen Removal In Photo-Sequencing Batch Reactor, Experiments, Dynamic Model And Full-Scale Design, Sahand Iman Shayan

USF Tampa Graduate Theses and Dissertations

Nitrogen is one of the essential elements for life; however, inefficient use of nitrogen creates major environmental problems. Nitrogen-rich streams from urban areas, farms, and wastewater treatment plants (WWTPs) lead to surface and groundwater contamination, resulting in eutrophication, hypoxia, and notable environmental, public health and economic damage. Ammonia is a form of nitrogen that can be created during industrial or biological nitrogen fixation or decomposition of biomass. Anaerobic digesters (ADs) in WWTP generate biogas from collected sludge from primary and secondary clarifiers to achieve energy recovery in the plant. However, sidestream effluent from dewatering AD sludge contains high concentrations of …

Effectiveness Of An Early Literacy Intervention For Increasing Teen Parents' Child-Directed Speech And Conversational Turns, Deborah H. Christie

USF Tampa Graduate Theses and Dissertations

Children’s language ability upon entry to kindergarten is a powerful predictor of reading achievement throughout elementary school; yet disparities in children’s language growth have been detected as early as 18 months of age. These disparities have been linked to the quantity and quality of speech provided to children as they are learning to talk. The current study employed a single-case multiple-baseline across participants experimental design to evaluate the effectiveness of an early literacy intervention to increase teen parents’ child-directed speech and conversational turns. The intervention was delivered one-on-one via videoconferencing by a teen parent peer coach. Participants included teen parents …

Constructing 'Child Safety': Policy, Practice, And Marginalized Families In Florida's Child Welfare System, Melissa Hope Johnson

USF Tampa Graduate Theses and Dissertations

‘Child safety’ has become a central concept of the modern child welfare system, an institution whose purpose is to protect children from abuse and neglect. What safety means and how it is best accomplished, however, are highly contested and characterized by definitional ambiguity, inconsistent bureaucratic interpretation, and operational variability. Situating this research within the anthropology of the state, the purpose of the current study is to develop a deeper understanding of the ways in which the state enacts power in matters of the family and childrearing through the child welfare system, casting a critical lens on the strategies used in …

Principal Preparation For The Bahamas: A Partnership Approach, Raquel R. Edgecombe

USF Tampa Graduate Theses and Dissertations

Current literature has investigated university-district partnerships in numerous ways; however, based on a review of the literature, no study has sought the insights of potential partners about the partnership arrangement prior to the start of the partnership agreement. The purpose of this study was to explore educational leadership practitioners’ understandings of partnership in principal preparation. This inquiry was guided by the following research questions: (a) How do educational stakeholders perceive the ideal partnership arrangement for the preparation of principals; and (b) In what ways do the perspectives of educational stakeholders reflect broader discourse about the quality of educational leadership preparation? …

Exercise Prescription Practices In University Counseling Centers: Testing The Information-Motivation-Behavioral Skills Model, A'Naja M. Newsome

USF Tampa Graduate Theses and Dissertations

The co-occurence of physical inactivity and poor mental health in the college student population can lead to chronic health issues that have negative short-term (e.g., academic success and weight gain) and long-term (e.g., obesity, serious mental illness, and premature mortality) impacts. Integrating exercise prescription into the mental health treatment plan of college students could enhance the holistic care model described by The American College Health Association (ACHA) and Healthy Campus task force. Understanding the knowledge, attitudes, and skills that mental health professionals (MHPs) hold regarding exercise prescription is important for policy formation and program development for college student health. The …

The Relationship Between Motivation And Professional Learning For Teachers In Makkah, Saudi Arabia, Yassir Alzahrani

USF Tampa Graduate Theses and Dissertations

Even though, there are many studies on teacher professional learning and many studies on teacher motivation, there is a lack of research to examine the relationship between teacher professional learning and motivation. This study examined the relationship between teacher motivation and professional learning in Makkah, Saudi Arabia.

This study was conducted using two instruments. The first instrument was the Education Participation Scale (EPS) originally developed by Boshier (1991). However, the researcher used the most recent version of EPS by Richter et al. (2019). The EPS determines what factors most motivate teachers to participate in professional development. These factors are personal …

Differential Privacy For Regression Modeling In Health: An Evaluation Of Algorithms, Joseph Ficek

USF Tampa Graduate Theses and Dissertations

Background: There is a need for rigorous and standardized methods of privacy protection for shared data in the health sciences. Differential privacy is one such method that has gained much popularity due to its versatility and robustness. This study evaluates differential privacy for explanatory regression modeling in the context of health research.

Methods: Surveyed and newly proposed algorithms were evaluated with respect to the accuracy (bias and RMSE) of coefficient estimates, the empirical coverage probability of confidence intervals, and the power and type I error rates of hypothesis tests. Evaluations took place in both simulated and real data from a …

Understanding Player And Clinician Perspectives On The Impact Of Problematic Gaming Behaviors In The United States, Amanda N. Weston

USF Tampa Graduate Theses and Dissertations

Due to the evolution of technology and increased use of video games, the need to understand how gaming affects individuals is imperative to assisting with those who struggle with problematic gaming behaviors. Video gaming has shown to have significant benefits including an increase in cognitive abilities, a way to relieve stress, and mood enhancement. However, problematic gaming behaviors (PGB) (i.e., uncontrollable gaming behaviors that impair functioning) may cause significant short and long-term problems that impact gamers throughout the lifespan if left untreated. There are critical gaps in the literature regarding how gaming impacts player functioning and how clinicians are managing …

Charter School Management: Mo Interaction With Educational Inputs And Outcomes, Joseph C. Simmons

USF Tampa Graduate Theses and Dissertations

This study seeks to understand if the utilization of a management company has any interaction with the socioeconomic status (SES) of students served, the school’s academic performance, the percentage English Language Learners served, the percentage of highly qualified teachers per school site, the amount of student attrition/mobility, or the amount of disciplinary events. Ultimately this study seeks to determine the efficacy and utility of management organization utilization by studying inputs and outputs of Florida charter schools and disaggregating them based on utilization of Charter Management Organizations, Education Management Organizations, or their decision not to utilize a Management Organization. This study …

Advice As Metadiscourse: On The Gendering Of Women's Leadership In Advice-Giving Practices, Amaly Santiago

USF Tampa Graduate Theses and Dissertations

This dissertation is about advice as social practice. Specifically, I examine leadership discourse as communicatively constituted and advice-giving as creating a metadiscourse of gendered abilities and leadership asymmetries. In the light of the growing number of initiatives created for women to improve their status as leaders, this project examines leadership, not as a quality, but as discourse: as a communicative dynamic. This is in line with how organizations see leadership when they create leadership programs, for these programs are designed to advise or teach women to be different and better leaders. My purpose is to encourage inclusiveness and contribute to …

Human-Centric Cybersecurity Research: From Trapping The Bad Guys To Helping The Good Ones, Armin Ziaie Tabari

USF Tampa Graduate Theses and Dissertations

The issue of cybersecurity has become much more prevalent over the last few years, with a number of widely publicised incidents, hacking attempts, and data breaches reaching the news. There is no sign of an abatement in the number of cyber incidents, and it would be wise to reconsider the way cybersecurity is viewed and whether a mindset shift is necessary. Cybersecurity, in general, can be seen as primarily a human problem, and it is for this reason that it requires human solutions and tradeoffs. In order to study this problem, using two perspectives; that of the adversaries and that …

Narratives Of Success: How Honors College Newcomers Frame The Entrance To College, Cayla Lanier

USF Tampa Graduate Theses and Dissertations

Starting college marks an important period of transition for young people, as they manage multiple changes at once and begin to establish identities independent from their parents. The first year college student experience has been the focus of a great deal of academic research, as scholars and practitioners seek to discover the best way to support students and ensure they remain successfully enrolled at the university. However, very little of this research attends to the specific experiences of Honors College students. Further, a focus on the communicative process of transitioning, or organizational socialization, may add to what is currently known. …

Machine Learning For Species Habitat Analysis, Abigail Lavallin

USF Tampa Graduate Theses and Dissertations

Management and conservation initiatives will always be controlled by finite resources, whether financialor temporal. Understanding a species’ spatial ecology, and how its requirements vary across habitats and locations is key to a successful species management plan. During recent decades, it has been noted how many species populations have declined, despite conservation practices working to increase their numbers. The most prevalent impacts affecting fauna populations have come from anthropogenic change in the form of habitat loss and destruction, along with fragmentation, and global climate change. There is a clear need for management practices to now operate on an entire landscape instead …

Modeling, Identification, And Stability Analysis Of Inverter-Based Resources Integrated Systems, Miao Zhang

USF Tampa Graduate Theses and Dissertations

More and more stability issues have been observed in real-world inverter-based resources (IBRs) power systems. Stability analysis is highly requested in the industrial area. To have an insight into the root causes of stability issues within IBR integrated systems, e.g, PV, wind, and battery storage systems, the dynamic characteristics should be fully understood.

The approaches are different when considering the presupposition of investigated IBR systems. A reduced-order analytical model of the IBR integrated system can be built if the IBR is treated as a white box. Since the parameters and control structures of converter control can be accessed. This analytical …

Theory And Algorithms For Systems Optimization, Vahid Mahmoodian

USF Tampa Graduate Theses and Dissertations

This dissertation presents four sets of contributions in the field of theory and algorithms for system optimization. In the first set, we introduce a simulation optimization method for redistributing bikes in a free-floating bike sharing system. The second set of contributions is a framework for batching queries in large databases to optimize the data retrieval time. The third set includes two branch-and-bound algorithms to solve minimum multiplicative programming problems and one branch-and-bound algorithm to solve the maximum form of the mentioned problems. At last, the fourth set presents an approach to fairlyassign delivery tasks in an outsourcing last-mile delivery system …

Testing The Congruence Of Espousals And Enactments Predicting Team Innovation, Rylan M. Charlton

USF Tampa Graduate Theses and Dissertations

This study employs a social identity perspective (Hogg, 2008) to test whether perceptions of both espoused and enacted values drive team innovation, and tests whether both their level and congruence determine their impact on innovation. This relationship is tested in a multilevel latent polynomial regression model (MLPM) framework (Zyphur, Zammuto, & Zhang, 2016). The study also leverages block variable procedures (e.g., Edwards & Cable, 2009) to model the combined effects of espoused and enacted values, and tests whether these combined effects mediate between leader behavior and team innovation. This represents the first test of Zohar and Hofmann’s (2012) proposition that …

Cool Under Fire: Psychopathic Traits And Decision-Making In Law Enforcement-Oriented Populations, Sean J. Mckinley

USF Tampa Graduate Theses and Dissertations

Law enforcement is an occupation that is typically characterized by high stress, physical danger, and potential for use of excessive force to subdue suspects of criminal activity. Compared to other jobs, the law enforcement profession is considered a high-stakes occupation that has the potential to greatly impact public safety, and officers must face daily dangers not experienced in other professions. While much research has focused on traditional models of personality and police performance (i.e., Big Five traits; Schneider, 2002; Twersky-Glasner, 2005), there may be utility in examining police officer performance through the lens of the triarchic psychopathy domains (Patrick, Fowles, …

Resilience And Health Outcomes Of Sexual Minority Middle-Aged And Older Adults, Christi L. Nelson

USF Tampa Graduate Theses and Dissertations

While research on lesbian, gay, and bisexual (hereafter referred to as sexual minority) middle-aged and older adults has increased over the past decade, there is still a critical need for more research on the health and resilience in this growing subpopulation. Research has provided evidence that sexual minority adults have an increased risk of negative health outcomes when compared to heterosexual adults. Research has also demonstrated possible resilience in sexual minority middle-aged and older adults; however, few studies have measured resilience in middle-aged and older adults. Gaining a better understanding of resilience in sexual minority adults may help identify modifiable …

Using Developmental Evaluation For Clinical Faculty Development In A New Academic Consortium, Candice Kunkle

USF Tampa Graduate Theses and Dissertations

This study aims to support the development of the series, particularly this evaluation study addresses the faculty development program within a newly formed academic partnership between teaching and community physicians. The evaluation addresses the opportunities, assets, and strengthens in the programming while constructing it for the intended users. While this study supports the evolution of the new program, it jointly enhances the collective’s efforts and innovative initiatives within a new academic partnership among leaders and clinical faculty through its ongoing development. The learning and actions derived from the assessments were guided by analysis from needs assessments and interviews as part …

Microbial Dark Matter: Culturing The Uncultured In Search Of Novel Chemotaxonomy, Sarah J. Kennedy

USF Tampa Graduate Theses and Dissertations

Although <1% of environmental isolates can be cultured, insights into the culturable fraction refine future techniques to unlock the cryptic biodiversity. This cryptic biodiversity is omnipresent within culture-independent surveys of environmental bacterial populations. Subsequently, these elusive organisms are termed “microbial dark matter” due to the intrigue surrounding their potential taxonomic and biosynthetic impacts. To this end of investigating bacterial-specific dark matter, we employed high-throughput culturing techniques to examine Gulf of Mexico sediments and sponges for chemotaxonomically important bacteria. Through stepwise implementation of permissive and selective recovery techniques, we succeeded in recovering over 150 unique bacterial isolates. We observed several isolates that pose as chemotaxonomically interesting, including several strains that belong to critical bioremediation taxa. In addition to these biotechnological-amenable isolates, we have also succeeded in culturing taxa historically attributed with antibacterial discoveries. One such isolate was a previously sponge-associated organism belonging to the rarely cultured Verrucosispora genus. Through extensive comparative genomics, we identified it as a novel species and subsequently named it Verrucosispora sioxanthis sp. nov. with the published genome serving as a resource for continued microbial dark matter investigations. Following continued passaging of the organism, we observed improved growth, biomass, and liquid growth dispersal within each increasingly sub-passaged generation of the isolate. As such, the laboratory attenuation, or domestication, of the organism warranted in-depth whole genomic analyses to generate insight into the increased laboratory sustainability. Through phenotypically-guided bioinformatics, we determined that the domestication was mediated through genome-wide selective pseudo- or non-pseudogenization of genes. As the previously sponge-associated organism evolved with the selection pressures of the static laboratory, we demonstrate that isolate effectively underwent genomic atrophy to resolve into a largely stable, sustainable laboratory-domesticated strain. Collectively, our chemotaxonomic discovery pipeline expands on the culturable bacterial biodiversity and ultimately provides a previously uncultured model organism for initial forays into resolving the microbial dark matter knowledge gap.

Learning, Planning For, And Reflecting On Teaching Mathematics For Social Justice: A Case Study Investigation Of A High School Mathematics Methods Course, Queshonda J. Kudaisi

USF Tampa Graduate Theses and Dissertations

While much is known about learning to teach for social justice in other content areas, less is known about how mathematics education students learn to teach mathematics for social justice, specifically at the high school level. Hence, this mixed-methods convergent case study addresses this gap in the research literature by examining and describing the experiences of mathematics education students learning to teach mathematics for social justice within the context of a high school mathematics methods course at a large research university in the southeastern United States. The data sources accessed for this study include a survey measuring beliefs about teaching …