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Socioeconomic Factors' And Water Source Features' Effect On Household Water Supply Choices In Uganda And The Associated Environmental Impacts, Christine M. Prouty

USF Tampa Graduate Theses and Dissertations

Over the last twenty years or more, Uganda has benefitted from significant strides in water and sanitation initiated by the United Nations' Millennium Development Goals. While the rapid progress towards development has been vastly beneficial, it is also important that it does not occur at the expense of the environment. The environmental impacts of these water sources must be evaluated and understood. However, to develop a robust understanding of the impact requires inclusion of the community members who use these sources and their perceptions of them. Consequently, the goal of this research is to investigate the interrelationships between socioeconomic factors, …

Cultivating Local: Building A Local Food System In Western North Carolina, Allison S. Perrett

USF Tampa Graduate Theses and Dissertations

This dissertation examines a movement in Western North Carolina to build a local food system, one grounded in the conditions and relationships of place. In 2000, Mountain Family Farms launched the Local Food Campaign to raise public awareness about the region's farms and farming heritage, to educate consumers about the benefits of buying food grown by local farms, and, ultimately, to build markets for locally grown food to sustain the region's farms. The campaign sparked a social movement and over a decade later local farms and locally grown food are a palpable feature of life in the mountains of Western …

Insight Into The Use, Perception, And Value Surrounding Domestic Water In Peru: Envisioning Demand Management In An Intermittent, Small-City, Service Context, Merril Augusta Putnam

USF Tampa Graduate Theses and Dissertations

Population growth, urbanization, degrading water quality, and climate change are making management of scarce water resources an increasingly difficult task for the domestic sector. It is recognized that in order to manage urban water resources demand management is requisite. Demand management has been experimented with in large cities of developing countries but continued focus on expanding supply overshadows its potential benefits and ultimate success. In order to manage demand, it must be measured and understood. Intermittent water services are prevalent in developing countries, but unmetered domestic water use under such conditions has not been carefully studied. This study conducted 1,149 …

Short And Long Term Volcano Instability Studies At Concepción Volcano, Nicaragua, Jose Armando Saballos

USF Tampa Graduate Theses and Dissertations

Concepción is the most active composite volcano in Nicaragua, and is located on Ometepe Island, within Lake Nicaragua. Moderate to small volcanic explosions with a volcanic explosivity index (VEI) of 1-2 have been characteristic of this volcano during the last four decades. Although its current activity is not violent, its volcanic deposits reveal stages of violent activity involving Plinian and sub-Plinian eruptions that deposited vast amounts of volcanic tephra in the Atlantic Ocean. These observations, together with the 31,000 people living on the island, make Concepción volcano an important target for volcanological research.

My research focuses on the investigation of …

Spatial Transferability Of Activity-Based Travel Forecasting Models, Sujan Sikder

USF Tampa Graduate Theses and Dissertations

Spatial transferability of travel forecasting models, or the ability to transfer models from one geographical region to another, can potentially help in significant cost and time savings for regions that cannot invest in extensive data-collection and model-development procedures. This issue is particularly important in the context of tour-based/activity-based models whose development typically involves significant data inputs, skilled staff, and long production times. However, most literature on model transferability has been in the context of traditionally used trip-based models, particularly for linear regression-based trip generation and logit-based mode choice models, with little evidence on the transferability of activity-based models and that …

Aspect Ratio Effect On Melting And Solidification During Thermal Energy Storage, Prashanth Sridharan

USF Tampa Graduate Theses and Dissertations

The present work investigates, numerically, the process of melting and solidification in hollow vertical cylinders, filled with air and phase change material (PCM). The PCM used is sodium nitrate, which expands upon melting. Therefore, a void must be present within the cylinder, which is filled with air. The influence of cylinder shape on melting time is determined. The numerical model takes both conductive and convective heat transfer into account during the melting process. The Volume-of-Fluid (VOF) model is used to track the interface between the PCM and air as the PCM melts. Three dimensionless numbers represent the characteristics of the …

Harmful Algal Blooms Of The West Florida Shelf And Campeche Bank: Visualization And Quantification Using Remote Sensing Methods, Inia Mariel Soto Ramos

USF Tampa Graduate Theses and Dissertations

Harmful Algal Blooms (HABs) in the Gulf of Mexico (GOM) are natural phenomena that can have negative impacts on marine ecosystems on which human health and the economy of some Gulf States depends. Many of the HABs in the GOM are dominated by the toxic dinoflagellate Karenia brevis. Non-toxic phytoplankton taxa such as Scrippsiella sp. also form intense blooms off the Mexican coast that result in massive fish mortality and economic losses, particularly as they may lead to anoxia.

The main objectives of this dissertation were to (1) evaluate and improve the techniques developed for detection of Karenia spp. blooms …

Spiritual Life Review With Older Adults: Finding Meaning In Late Life Development, Alicia Margaret Stinson

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Spirituality has been recognized as a positive factor in the lives of older adults, especially as it influences their emotional, mental, and physical well-being. This convenience sample study included 17 older adults residing at a faith based continuing care retirement community in Florida. The sample was represented by Caucasian older adults with an average age of 84 years, highly educated, majority Protestant and mostly female. Spiritual life reviews were conducted using spiritual life maps (Hodge, 2005) and semi-structured interview questions. Erikson's epigenetic stage of ego-integrity was used along with Butler's life review process and Tornstam's gerotranscendence as a conceptual …

Time Scale Of Groundwater Recharge: A Generalized Modeling Technique, Makhan Virdi

USF Tampa Graduate Theses and Dissertations

Estimating the quantity of water that reaches the water table following an infiltration event is vital for modeling and management of water resources. Estimating the time scale of groundwater recharge after a rainfall event is difficult because of the dependence on nonlinear soil characteristics and variability in antecedent conditions. Modeling the flow of water through the variably saturated zone is computationally intensive since it requires simulation of Richards' equation, a nonlinear partial differential equation without a closed-form analytical solution, with parametric relationships that are difficult to approximate. Hence, regional scale coupled (surface water - groundwater) hydrological models make simplistic assumptions …

Anti-Parasitic And Anti-Bacterial Agents: Studies On 1,4-Dihydropyridines And 2,4-Diaminoquinazolines, Kurt Steven Van Horn

USF Tampa Graduate Theses and Dissertations

Thirty-three 1,4-dihydropyridine diastereomeric pairs were synthesized and the structure-activity relationship studied in a Plasmodium falciparum in vitro model. Twenty-nine of these derivatives contained a 6-position oxygen, with 2.31, 2.32, 2.52 and 2.53 having single and double digit nanomolar activities. This SAR study revealed some insightful information about the 1,4-dihydropyridine substitution pattern. Substitution at the 7-position other than 3,4-dimethoxy severely reduced the activity. 4-phenyl substitution with 2- or 4- halo or methyl formed active compounds while substitution at the 3-position or with methoxy or conjugated aryl systems resulted in inactive compounds. The 2-position was found to majorly affect the activity, with …

A Case Study Of Peer Review Practices Of Four Adolescent English Language Learners In Face-To-Face And Online Contexts, Oksana Vorobel

USF Tampa Graduate Theses and Dissertations

Peer review is a complex collaborative activity, which may engage English language learners in reading, writing, listening, and speaking and carry many potential benefits for their language learning (Hu, 2005). While many research studies focused on peer review practices of adult language learners in academic settings in the USA or abroad in language classes (Grami, 2010; Zhao, 2010), little attention was paid to adolescent L2 writers participating in peer review in face-to-face K-12 and online contexts. This multiple case study aimed at describing and explaining peer review practices of four adolescent ELLs in face-to-face and online contexts from the ecological …

Effect Of Bolted Joint Preload On Structural Damping, Weiwei Xu

USF Tampa Graduate Theses and Dissertations

Bolted joints are integral parts of mechanical systems, and bolt preload loss is one of the major failure modes for bolted joint structures. Understanding the damping and frequency response to a varying preload in a single-bolted lap-joint structure can be very helpful in predicting and analyzing more complicated structures connected by these joints.

In this thesis, the relationship between the bolt preload and the natural frequency, and the relationship between the bolt preload and the structural damping, have both been investigated through impact hammer testing on a single-bolted lap-joint structure. The test data revealed that the bolt preload has nonlinear …

Preparing Teachers To Apply Research To Mathematics Teaching: Using Design-Based Research To Define And Assess The Process Of Evidence-Based Practice, Sarah Van Ingen

USF Tampa Graduate Theses and Dissertations

Persistent lack of mathematics achievement and disparity in achievement has led to the publication of research findings related to equitable teaching practices. Although the publication of such research provides insights about approaches for potentially increasing equity in mathematics education, teachers must be able to apply what has been learned from these studies to their classroom teaching practices. Despite the widespread expectation that teachers use research-supported teaching strategies to meet the needs of their diverse classrooms, the research to practice gap persists. Little research is currently available to guide mathematics teacher educators in how to prepare future teachers to apply research …

Statistical Analysis And Modeling Of Prostate Cancer, Yiu Ming Chan

USF Tampa Graduate Theses and Dissertations

The objective of the present study is to address some important questions related to prostate cancer treatments and survivorship among White and African American men. It is commonly understood that the risk of developing prostate cancer is higher in African American men than the other races. However, using parametric analysis, this study demonstrates that this perception is a "myth" not a "reality". The study further identifies the existence of racial/ethnic disparities by comparing the average mean tumor size, the median of survival time, and the survival function between White and African American men. These results underline the necessity of understanding …

Optimization, Modification And Application Of Gold Nanoparticles As The Substrates Of Surface Enhanced Raman Spectroscopy, Seongmin Hong

USF Tampa Graduate Theses and Dissertations

SERS

A Monte Carlo Approach To Change Point Detection In A Liver Transplant, Alexia Melissa Makris

USF Tampa Graduate Theses and Dissertations

Patient survival post liver transplant (LT) is important to both the patient and the center's accreditation, but over the years physicians have noticed that distant patients struggle with post LT care. I hypothesized that patient's distance from the transplant center had a detrimental effect on post LT survival. I suspected Hepatitis C (HCV) and Hepatocellular Carcinoma (HCC) patients would deteriorate due to their recurrent disease and there is a need for close monitoring post LT. From the current literature it was not clear if patients' distance from a transplant center affects outcomes post LT. Firozvi et al. (Firozvi AA, 2008) …

Modeling Potential Chemical Environments: Implications For Astrobiology, Brian Craig Szenay

USF Tampa Graduate Theses and Dissertations

Modeling chemical environments is an important step to understanding the diversity of prebiotic systems that may have formed on the early earth or potentially can occur on other worlds. By using the modern Earth as a test case, these models predict scenarios with systems more conducive to the formation of the organic molecules that are important to life. Here we use the equilibrium thermodynamic modeling program HSC Chem to investigate prebiotic environments. This program uses the raw material that the user inputs into the system in order to calculate the change in amounts of chemical species forming as a function …

Guanxi, Networks And Economic Development: The Impact Of Cultural Connections, Patricia Anne Weeks

USF Tampa Graduate Theses and Dissertations

The purpose of this study is to explore the mechanics of guanxi in an organizational setting, focusing on the use of interpersonal relationships within Chinese firms to discover how firms initiate, build and use guanxi networks. Two richly detailed case studies document changes that take place over time in two distinct networks with respect to key actors and their contacts. This research also investigates patterns of social structure that emerge over time in these two distinct cases looking at brokerage relationships, network density, and dyadic redundancy in three waves at six month intervals. The cases are dissimilar in all aspects …

Development Of A Novel Method For Deriving Thresholds Of Toxicological Concern (Ttcs) For Vaccine Constituents, Jennifer Jessica White

USF Tampa Graduate Theses and Dissertations

Abstract

Safety assessment relating to the presence of impurities, residual materials and contaminants in vaccines is a focus area of research at the United States Food and Drug Administration (FDA). Sponsors who submit Investigational New Drug (IND) applications for new vaccine products must report the results of safety assessments to the Division of Vaccines and Related Products Applications (DVRPA). Scientifically defining thresholds of toxicological concern (TTCs) as they apply to vaccine constituents will provide a useful aid to the sponsors and public regarding safety assessments of compounds for which there is little or no toxicity data. TTCs are mathematically modeled …

Synthesis Of Amphiphilic Α- And Γ-Aapeptides For Antimicrobial, Self-Assembly, And Mineralization Studies, Mohamad N. Amin

USF Tampa Graduate Theses and Dissertations

Seven novel, amphiphilic AApeptides were prepared. Two cationic, lipo-α-AApeptides, NA-75 and NA-77 were found to possess potent antimicrobial activity against Gram-positive bacteria, with almost no hemolytic activity. In addition to NA-75 and 77, four amphiphilic, γ-AApeptides, NA-133, 135, 137, and 139, and one anionic lipo-α-AApeptide, NA-81, were prepared for molecular self-assembly studies, with several interesting nanostructures observed by TEM. Mineralization of calcium carbonate from gaseous CO2 and Ca2+ in the presence of the 7 AApeptide amphiphiles was also observed by optical microscopy. Several AApeptides were found to be able to influence CaCO3 crystal morphology. Another α-AApeptide, NA-63, was synthesized by …

Investigation Of Colored Dissolved Organic Matter (Cdom) Optical Properties, Nutrients, And Salinity In Coastal Florida: Springshed To Estuaries, Ana Rosa Arellano

USF Tampa Graduate Theses and Dissertations

Optical parameters measured via absorption spectroscopy and high-resolution fluorescence spectroscopy were used to characterize dissolved organic matter (DOM) in the springshed of Kings Bay, a spring-fed estuary located on Florida's Springs Coast. Over the past 40 years, springs supplying groundwater to Kings Bay have shown an increase in nitrate concentration. The overall goal of this project was to fingerprint wells and spring sites with elevated nitrogen concentrations using CDOM optical properties and establish relationships between nutrient and optical parameters. Samples were obtained from various sites: springs, Kings Bay surface (KBS), wells, coastal waters in and at the mouth of Crystal …

Development Of Nanostructured Graphene/Conducting Polymer Composite Materials For Supercapacitor Applications, Punya A. Basnayaka

USF Tampa Graduate Theses and Dissertations

The developments in mobile/portable electronics and alternative energy vehicles prompted engineers and researchers to develop electrochemical energy storage devices called supercapacitors, as the third generation type capacitors. Most of the research and development on supercapacitors focus on electrode materials, electrolytes and hybridization. Some attempts have been directed towards increasing the energy density by employing electroactive materials, such as metal oxides and conducting polymers (CPs). However, the high cost and toxicity of applicable metal oxides and poor long term stability of CPs paved the way to alternative electrode materials. The electroactive materials with carbon particles in composites have been used substantially …

Reading Assessment Practices Of Elementary General Education Teachers: A Descriptive Study, Sarah Mirlenbrink Bombly

USF Tampa Graduate Theses and Dissertations

In this descriptive study, I researched five elementary general education teachers' reading assessment practices as they worked within the context of IDEA (2004), NCLB (2002) and Response to Intervention (RTI). My own connection to the classroom and reading assessment practices brought me to this research. I presented my personal and professional connection through vignettes about my own classroom assessment practices. Relevant literature on both the context and culture of assessment were pertinent to this research.

I used a qualitative design, specifically, Colaizzi's (1978) method of phenomenological analysis. Data were three in-depth phenomenological interviews, relevant documents and artifacts, and use of …

Morphological Changes Associated With Tropical Storm Debby In The Vicinity Of Two Tidal Inlets, John's Pass And Blind Pass, West-Central Florida, Andrew Brownell

USF Tampa Graduate Theses and Dissertations

Tropical Storm Debby affected the Gulf coast of Florida in late June, 2012. The storm's southerly approach temporarily reversed the annual net southward longshore sediment transport. The energetic conditions associated with Tropical Storm Debby can be seen in the wind, wave and tidal measurements taken from both onshore and offshore weather stations around the dual tidal inlets system of John's Pass and Blind Pass, approximately 25 kilometers north of the mouth of Tampa Bay. The energetic and persistent southerly forcing, in addition to higher storm induced water levels and wave heights, resulted in atypical beach erosion and sediment deposition on …

Defining Semantic Space And Degree Of Association Using Brainwaves: An Erp Investigation Of Alcohol Expectancies, Ty Brumback

USF Tampa Graduate Theses and Dissertations

The current study investigated the cognitive organization of alcohol expectancies using event-related potentials (ERPs). Building on previous behavioral and ERP paradigms, the goal of the current study was to quantify the relationship among alcohol expectancies using ERP indices of salience, congruence, and cognitive distance. The ERP components being evaluated fit perfectly into the alcohol expectancy theory and research; however, implementing specific paradigms to reliably measure individual differences in alcohol expectancies using ERPs has proven to be more elusive than originally thought. This study utilized established cognitive modeling techniques coupled with ERP responses to linguistic stimuli. In essence, this study provides …

Application And Characterization Of Self-Assembled Monolayers In Hybrid Electronic Systems, Michael Enoch Celesin

USF Tampa Graduate Theses and Dissertations

In this study, we explore ultra-thin insulators of organic and inorganic composition and their potential role as high-speed rectifiers. Typical applications for these structures include IR sensing, chemical detection, high speed logic circuits, and MEMS enhancements. While there are many elements in the functional group required to create a rectifying antenna (rectenna), the primary thrust of this work is on the rectifier element itself.

To achieve these research goals, a very good understanding of quantum tunneling was required to model the underlying phenomenon of charge conduction. The development of a multi-variable optimization routine for tunneling prediction was required. MATLAB was …

Magnetization Dynamics And Related Phenomena In Nanostructures, Sayan Chandra

USF Tampa Graduate Theses and Dissertations

Collective magnetic behavior in nanostructures is a phenomenon commonly observed in various magnetic systems. It arises due to competing inter/intra–particle interactions and size distribution and can manifest in phenomena like magnetic freezing, magnetic aging, and exchange bias (EB) effect. In order to probe these rather complex phenomena, conventional DC and AC magnetic measurements have been performed along with radio–frequency transverse susceptibility (TS) measurements. We also demonstrate the magnetic entropy change as a parameter sensitive to subtle changes in the magnetization dynamics of nanostructures. The focus of this dissertation is to study the collective magnetic behavior in core-shell nanostructures of Fe/γ–Fe …

Predictors Of Student Enrollment Patterns In High School Career Academies, E. Daniel Cox

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to describe participation patterns at the district level of students enrolled in career academies and determine whether participation in career academies is a function of demographic and/or prior learning experience and prior performance variables. Ex-post facto data was used to determine six-year enrollment trends. In addition, both binary logistic regression and multinomial logistic regression methods were employed to determine the extent demographic along with prior learning experience and prior performance variables could be used to predict participation within career academies. Trend data results indicated slight increases in the proportions of students of color (including …

Distinguishing Processes That Induce Temporal Beach Profile Changes Using Principal Component Analysis: A Case Study At Long Key, West-Central Florida, Denise Marie Davis

USF Tampa Graduate Theses and Dissertations

The heavily developed Long Key is located in Pinellas County in west-central Florida. The structured Blind Pass at the north end of the barrier island interrupts the southward longshore sediment transport, resulting in severe and chronic beach erosion along the northern portion of the island. Frequent beach nourishments were conducted to mitigate the erosion. In this study, the performance of the most recent beach nourishment in 2010 is quantified through time-series beach profile surveys. Over the 34-month period, the nourished northern portion of the island, Upham Beach, lost up to 330 m3/m of sand, with a landward shoreline retreat of …

An(Other) Rhetoric: Rhetoric, Ethics, And The Rhetorical Tradition, Kathleen Sandell Hardesty

USF Tampa Graduate Theses and Dissertations

Rhetoric as a discipline is still touched by the shadow of ancient Greece. Rhetoric was defined famously by Aristotle as the "available means of persuasion," codified into five canons in classical Rome, and has since been a central part of Western education to train speakers and writers to effectively move their audiences. However, particularly beginning in the mid-20th Century, the discipline's understanding of rhetoric as a means of persuasion (or even manipulation) passed down from our ancient roots began to shift to a sense of rhetoric as matters of ethics and a concern for the other. It begs the question: …