Digital Commons Network^™

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 …

Unraveling The Role Of Novel G5 Peptidase Family Proteins In Virulence And Cell Envelope Biogenesis Of Staphylococcus Aureus, Stephanie M. Marroquin

USF Tampa Graduate Theses and Dissertations

Virulence factors and the bacterial cell envelope are two important components in S. aureus pathogenesis and survival. More importantly, understanding the regulation of these cellular processes is crucial to further understanding and combating this successful pathogen. To date, numerous factors have been identified as playing a role in the regulation of Agr activity in S. aureus, including transcription factors, antisense RNAs, and host elements. Herein we investigate the product of SAUSA300_1984 (termed MroQ), a transmembrane G5 peptidase family protein, as a novel effector of this system. Using a USA300 mroQ mutant we observed a drastic reduction in proteolysis, hemolysis, and …

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 …

Incarnational Literacy: Multimodal Explorations Through Virtual Reality And Transformational Autoethnography, Csaba Osvath

USF Tampa Graduate Theses and Dissertations

Incarnational literacy is a multimodal, maker-centered, arts-based literacy engagement. As an emerging method and theoretical orientation, it incorporates core principles and transformative tools from the domains of creativity, arts-based inquiry, literacy, and spirituality. This experimental, multimodal dissertation chronicles the conception and ongoing development of incarnational literacy through a series of autoethnographic narratives, demonstrating the existential benefits of the integrated practice of artmaking and literacy engagements. This study also highlights the role and function of videogames and virtual reality experiences, revealing the benefits of introspective gameplay as tools of inquiry and meaning-making - further enriching the developing practice and domain of …

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, …

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 …

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 …

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 …

Exploration Of Post-Merger Integration Meetings, Through A Qualitative Study Of Individuals’ Perceptions, Ruben Cintron

USF Tampa Graduate Theses and Dissertations

In 2020, the United Sates mergers and acquisitions (M&As) had a total value of $1.2 trillion. Organizations engage in M&As for a variety of reasons, such as to gain economies of scale and scope, obtain technologies, enter new markets, or gain competitive advantage by eliminating competitors or combining forces. However, studies indicate that less than half achieve their stated strategic and financial goals. Two factors cited within the M&A literature that contribute to the failure rate are cultural clashes and post-merger integration activities. This three-paper dissertation explores the influence organizational cultures and post-merger integration activity (post-merger meetings) may have on …

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 …

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 …

Gamifying The Crew: Effects Of Collaborative Responsive Writing Using Gamification, In Interactive Web-Based E-Books, On L2 International Students’ Motivation And Academic Vocabulary Achievement, Rabea M. Alfahad

USF Tampa Graduate Theses and Dissertations

International students usually find it challenging to adapt to English academic vocabulary (Park, 2019). The literature is interspersed with the use of a variety of technologies and technological tools to augment the knowledge of language learners regarding English academic vocabulary (Flemban, 2018). However, in this dissertation, interactive web-based e-books and two strategies to teach English academic vocabulary (gamification and collaborative responsive writing) is employed. Gamification is applying game mechanics in non-game related contexts (Groh, 2012). This study investigated the impact of these two strategies on the participants’ academic vocabulary achievement and motivation level. In so doing, interactive web-based e-books are …

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 …

Microencapsulation Of Thermochromic Materials For Thermal Storage And Energy Efficiency Of Buildings, Abdullatif Hakami

USF Tampa Graduate Theses and Dissertations

Thermochromism and thermochromic materials research and development are of great interest in various applications such as energy efficient building structures, textile industries, thermal or heat storage, antique maintenance processing, and sensors, etc. In general, thermochromic materials have been classified into four categories, including inorganic, organic, polymeric, and hybrid systems, based on their unique material properties and operating conditions. Thermochromic materials have been prepared via different physico-chemical techniques with some of them combined to maximize the yield, stability, and efficiency of the prepared TCMs. Pristine TCMs often undergo severe degradation when exposed to various external stimuli including UV irradiation from sunlight …

Investigation Of Immobilized Enzymes In Confined Environment Of Mesoporous Host Matrices, Xiaoliang Wang

USF Tampa Graduate Theses and Dissertations

Enzyme immobilization in metal-organic frameworks (MOFs) as a promising strategy, is attracting the interest of scientists from different disciplines with the expansion of MOF’s development. Different from other traditional host materials, their unique strengths of high surface areas, large yet adjustable pore sizes, functionalizable pore walls, and diverse architectures make MOFs an ideal platform to investigate hosted enzymes, which is critical to the industrial and commercial process. In addition to the protective function of MOFs, the extensive roles of MOFs in the enzyme immobilization are being well-explored by making full use of their remarkable properties like well-defined structure, high porosity, …

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 …

Online Perceptions Of Panamanian Prisons And Incarcerated Persons: An Analysis Of Youtube User Comments, Mahaleth J. Sotelo

USF Tampa Graduate Theses and Dissertations

The purpose of this study is to explore and understand the frameworks in which prisons and incarcerated persons are discussed amongst commenters under YouTube videos displaying media on Panamanian prisons. The study incorporates a mixed methods approach by conducting a general content analysis of YouTuber comments to address themes within the discussion. Additionally, these themes were quantified and modeled using predictive variables collected such as number of comment likes, number of comment dislikes, and number of comment replies, alias type (screen name or name-like), presence of profile picture, and profile picture type. The themes found were 1) punitive, 2) justifying …

Sanitation Marketing In Uganda: The Impact Of Gender On Participation And Outcomes, Elizabeth Vicario

USF Tampa Graduate Theses and Dissertations

Uganda aims to reach universal access to basic sanitation under Sustainable Development Goal #6, but achieving this target by 2030 would require doubling the annual rate of progress. Women are disproportionately affected by poor sanitation due to their health needs and risk of facing violence, but they have historically been excluded from sanitation planning. Low household demand and poor service delivery have stalled progress in Uganda. Market-based sanitation (MBS) is a novel method of developing a sanitation market through stimulating demand and supporting a competitive atmosphere for product and service providers. This research studies the sanitation marketing activities implemented by …

Use Of Biochar And Zeolite For Landfill Leachate Treatment: Experimental Studies And Reuse Potential Assessment, Thanh Thieu Lam

USF Tampa Graduate Theses and Dissertations

Leachate is a highly colored liquid waste product of landfills that contains high concentrations of ammonia nitrogen (NH4+-N), refractory organic matter, and heavy metals. It is commonly disposed to local publicly owned treatment works (POTWs). With these potent characteristics, it interferes with the physical, biological, and chemical treatment processes within POTWs. Sequencing batch biofilm reactors (SBBR) and hybrid subsurface flow constructed wetlands (CW) have been used in the past to treat landfill leachate, but their design and performance can still be optimized. Addition of low-cost adsorbent materials to SBBRs and CWs, such as biochar and zeolite, have the potential to …

A Functional Characterization Of The Omega (Ω) Subunit Of Rna Polymerase In Staphylococcus Aureus, Shrushti B. Patil

USF Tampa Graduate Theses and Dissertations

In bacteria, RNA polymerase (RNAP) is a well-characterized and highly conserved multi-subunit enzyme complex responsible for transcription of DNA into RNA. The ω subunit (rpoZ/RpoZ), one of the smaller accessory subunits of RNAP, is often overlooked and under-studied, however, particularly in Gram-positive species. We have previously shown that deleting ω impacts the integrity of RNA polymerase in S. aureus, especially the β' subunit, and alters preference of the core enzyme for sigma factors, skewing heavily towards σB instead of the housekeeping σ factor. Consequently, this causes deregulation of myriad transcriptional processes, strongly rewiring gene expression circuits, and ultimately impairing the …

Application Of Gold Nanoshells For Photothermal Therapy In Lung Cancer Cells, Yva K. Luc

USF Tampa Graduate Theses and Dissertations

Lung cancer is the leading cause of cancer deaths in the world. For the year 2020, it was estimated 1.8 million deaths were due to lung cancer alone, making it more lethal than breast cancer and prostate cancer combined. For the year 2021, it is estimated 235,760 new cases of lung cancer and 50% will lead to death. The primary cause of lung cancer is due to cigarette smoking, which accounts for 80% of all lung cancer deaths. Lung cancer screening relies on only different methods, biopsy, bronchoscopy, ultrasound, chest x-ray film, and sputum cytology. These techniques are used to …

Investigation Of An Alternative Protocol For The Production Of Sars-Cov-2 Antigenic Proteins, Nichole Ninaltowski

USF Tampa Graduate Theses and Dissertations

With the COVID-19 pandemic showing no signs of slowing down, large-scale antigenic protein production is still needed for surveillance using serologic assays. From screening to vaccines to biotherapeutics, being able to produce the proteins for these assays is essential; however, the current gold standard method for producing SARS-CoV-2 spike proteins is prohibitively expensive for most research groups.

Alternative methods of transfecting mammalian cells to produce recombinant proteins that are relatively inexpensive have been used for years. Unlike the expensive, commercially available lipid-based methods, other established methods such as polyethyleneimine (PEI), are considerably easier, and cheaper to meet the needs of …

Community Assessment Of Water Perceptions And Household Point-Of-Use Treatment Methods In Madagascar, Isabella Rose Silverman

USF Tampa Graduate Theses and Dissertations

One in four people around the world do not have access to safe drinking water, which means that two billion people globally lack access. In high-income countries, 0.02% of yearly deaths are attributed to unsafe water sources; however, an alarming 10.6% of deaths occur in Madagascar, for the same reason.

To achieve Sustainable Development Goal 6: Ensure access to water and sanitation for all, a collaboration between public health and engineering is critical. Within the public health sector, social marketing is commonly utilized to address a problem by using commercial marketing principles to change behavior for the good of society. …

Quercetin Loaded Nanoparticles For The Treatment Of Dry Eye Disease, Bassma Sami Nashaat Hamed Eltanameli

USF Tampa Graduate Theses and Dissertations

Dry eye disease (DED) is a common condition that affects the eye's anterior surface due to tear deficiency or excessive evaporation. The lack of tears leads to dryness and initiation of an inflammatory response which can irritate the eye and interfere with daily activities. Current treatment depends mainly on artificial tears eye drops which offer temporary relief and require repetitive administration due to frequent blinking. Prescription medications are also available but need around three months to relieve dry eye symptoms. Quercetin is a flavonoid that has an anti-inflammatory and antioxidant effect. However, it suffers from low water solubility and low …

The Media Reproduction Of Racial Violence: A Content Analysis Of News Coverage Following The Death Of George Floyd Jr., Keylon Lovett

USF Tampa Graduate Theses and Dissertations

The media has played a critical role in reproducing anti-Black violence in the United States, which has often harmed African American communities. Historically, the white press has depicted graphic imagery and descriptions of Black people being brutalized, with little ethical regard to their harmful effects. The Black press has historically challenged negative portrayals in the white media and shown more nuance, to protect the Black audience it represents. This dynamic underpins media depictions of racial violence still seen today. Darnella Frazier’s video capture of George Floyd’s death by Minneapolis police, was widely shared in the weeks following the incident, across …

The Multifaceted Role Of Ccar-1 In The Alternative Splicing And Germline Regulation In Caenorhabditis Elegans, Doreen Ikhuva Lugano

USF Tampa Graduate Theses and Dissertations

The Cell Division Cycle and Apoptosis Regulator (CCAR) family members are an enigmatic family of proteins regulating metabolism, cancer, apoptosis, DNA damage, and stress. Mammals have CCAR family members, CCAR1 and CCAR2/DBC1, which evolved from the founding family member CCAR-1/LST-3 expressed in Caenorhabditis elegans. Several studies have shown the importance of understanding these proteins' function in standard and altered physiological processes. Our studies aim to understand the genome-wide alternative splicing and germline regulation of Caenorhabditis elegans CCAR-1 in normal and heat shock conditions. Recently, mammalian CCAR family member CCAR2/DBC1 regulates the alternative splicing by forming a complex with ZNF326. This …

Criminalizing Lgbtq+ Jamaicans: Social, Legal, And Colonial Influences On Homophobic Policy, Zoe C. Knowles

USF Tampa Graduate Theses and Dissertations

Based on colonial and neocolonial models of oppression, Jamaica has adopted many laws, policies, and systems mandated by the British monarchy. Many of these laws contain anti-LGBTQ+ policies which remain in effect today. To address the criminalization of LGBTQ+ identities, I used queer theory and queer criminology to analyse the ways Jamaica constructs LGBTQ+ people as criminals and how they are treated in the legal and criminal justice systems from a postcolonial standpoint. Using a qualitative text-based feminist and queer policy analysis, I investigated social, legal, and colonial influences on current anti-LGBTQ+ policy by looking at the Offences Against the …