Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

USF Tampa Graduate Theses and Dissertations

Discipline
Keyword
Publication Year
File Type

Articles 1171 - 1200 of 1834

Full-Text Articles in Physical Sciences and Mathematics

Gamma Aapeptides As Host Defense Peptide Mimics, Yaqiong Li May 2016

Gamma Aapeptides As Host Defense Peptide Mimics, Yaqiong Li

USF Tampa Graduate Theses and Dissertations

There has been increasing concern regarding the emergence of multi-drug resistant pathogens. The resistance develops when pathogens, especially bacteria, are frequently exposed to conventional antibiotics, as they are heavily used in both human and livestock. This is due to the high target specificity of conventional antibiotics, which places pathogens in high selective pressures and eventually results in drug resistant by mutations. To address this issue, global actions and cooperation are needed. At the same time, new technologies and strategies need to be developed. Host defense peptides (HDPs) are widely found in the innate immune system. They show both direct antimicrobial …


Morphodynamics Of Egmont Key At The Mouth Of Tampa Bay: West-Central Florida, Zachary James Tyler Apr 2016

Morphodynamics Of Egmont Key At The Mouth Of Tampa Bay: West-Central Florida, Zachary James Tyler

USF Tampa Graduate Theses and Dissertations

Egmont Key, located at the mouth of Tampa Bay, is part of a dynamic system with many interrelated natural and anthropogenic factors influencing its morphodynamics. This study started in August 2012. During the 3-year period until August 2015, 28 beach profile transects were established and surveyed 10 times. Seventeen historical aerial images from 1942 to 2013 were geo-rectified and analyzed. Three hundred and fourteen sediment samples were procured from the navigation channel dredge area and the beach nourishment area and analyzed for grain size. A numerical wave model was established to simulate the nearshore wave field. The overall goals of …


Chiral Boro-Phosphates In Asymmetric Catalysis: 1,4-Reduction Of Enones And Reductive Aldol, Susana Sorina Lopez Apr 2016

Chiral Boro-Phosphates In Asymmetric Catalysis: 1,4-Reduction Of Enones And Reductive Aldol, Susana Sorina Lopez

USF Tampa Graduate Theses and Dissertations

The biological activity of the pharmaceutical drugs often depends on how it fits with a receptor making stereochemistry a key component. Selective reactions can limit or avoid the mixture of enantiomers obtained. One such reaction is the selective reduction of a carbon-carbon double bond in the presence of a carbonyl. Although efficient, current asymmetric synthesis methods have limitations such as harsh reaction conditions, the high costs of chiral catalysts and the toxicity of the metal-based catalysts. Catalysts derived from small organic molecules have become an attractive alternative which have been explored more rigorously in recent years. Using a BINOL-derived boro-phosphate …


Renewable Energy Investment Planning And Policy Design, Alireza Ghalebani Apr 2016

Renewable Energy Investment Planning And Policy Design, Alireza Ghalebani

USF Tampa Graduate Theses and Dissertations

In this dissertation, we leverage predictive and prescriptive analytics to develop decision support systems to promote the use of renewable energy in society. Since electricity from renewable energy sources is still relatively expensive, there are variety of financial incentive programs available in different regions. Our research focuses on financial incentive programs and tackles two main problem: 1) how to optimally design and control hybrid renewable energy systems for residential and commercial buildings given the capacity based and performance based incentives, and 2) how to develop a model-based system for policy makers for designing optimal financial incentive programs to promote investment …


The Role Of Social Ties In Dynamic Networks, Xiang Zuo Apr 2016

The Role Of Social Ties In Dynamic Networks, Xiang Zuo

USF Tampa Graduate Theses and Dissertations

Social networks are everywhere, from face-to-face activities to online social networks such as Flickr, YouTube and Facebook. In social networks, ties (relationships) are connections between people. The change of social relationships over time consequently leads to the evolution of the social network structure. At the same time, ties serve as carriers to transfer pieces of information from one person to another.

Studying social ties is critical to understanding the fundamental processes behind the network. Although many studies on social networks have been carried out over the last many decades, most of the work either used small in-lab datasets, or focused …


Design Exploration And Application Of Reversible Circuits In Emerging Technologies, Saurabh Kotiyal Apr 2016

Design Exploration And Application Of Reversible Circuits In Emerging Technologies, Saurabh Kotiyal

USF Tampa Graduate Theses and Dissertations

The reversible logic has promising applications in emerging computing paradigms, such as quantum computing, quantum dot cellular automata, optical computing, etc. In reversible logic gates, there is a unique one-to-one mapping between the inputs and outputs. To generate a useful gate function, the reversible gates require some constant ancillary inputs called ancilla inputs. Also to maintain the reversibility of the circuits some additional unused outputs are required that are referred to as the garbage outputs. The number of ancilla inputs, the number of garbage outputs and quantum cost plays an important role in the evaluation of reversible circuits. Thus minimizing …


Co(Ii)-Based Metalloradical Catalysis For Asymmetric Radical Cyclopropanation, Qigan Cheng Apr 2016

Co(Ii)-Based Metalloradical Catalysis For Asymmetric Radical Cyclopropanation, Qigan Cheng

USF Tampa Graduate Theses and Dissertations

Metal-catalyzed cyclopropanation of olefins with diazo reagents is one of the most general and efficient method to prepare cyclopropanes. The resulting cyclopropyl units are found as a basic structural element in a wide range of naturally occurring compounds and biologically active compounds, and can serve as versatile synthetic intermediates in the synthesis of multifunctionalized cycloalkanes and acyclic compounds. Since Co(II) complexes of D2-symmetric chiral amidoporphyrins [Co(D2-Por*)] were first introduced in 2004, Co(II)-metalloradical catalysis (MRC) have emerged as a new platform for asymmetric cyclopropanation. These metalloradical catalysts have been shown to be highly effective for asymmetric intermolecular …


The Use Of Synthetic Mixture Based Libraries To Identify Hit Compounds For Eskape Pathogens, Leishmaniasis, And Inhibitors Of Palmitoylation, Marcello Giulianotti Apr 2016

The Use Of Synthetic Mixture Based Libraries To Identify Hit Compounds For Eskape Pathogens, Leishmaniasis, And Inhibitors Of Palmitoylation, Marcello Giulianotti

USF Tampa Graduate Theses and Dissertations

The goal of this work is to demonstrate the utility of using systematically formatted mixture based libraries as part of the drug discovery processes. While there are a number of different valid approaches for identifying hit and tool compounds, systematically formatted mixture based libraries, such as those described in this study, offer the ability to develop a significant amount of structure activity relationship data from the testing of very few samples. In support of this claim a review of recent developments in the area of systematically formatted mixture based libraries as well as three case studies are presented. The three …


Evaluation Of Pulmonary Function Among Workers Engaged In The Manufacture Of Hydraulic Fracking Ceramic Proppant, Humairat H. Rahman Apr 2016

Evaluation Of Pulmonary Function Among Workers Engaged In The Manufacture Of Hydraulic Fracking Ceramic Proppant, Humairat H. Rahman

USF Tampa Graduate Theses and Dissertations

Workers involved in hydraulic fracking processes are exposed to various types of chemicals and dusts in their workplaces, such as proppants, which hold open the fissures created in the fracking process. Recently, ceramic proppants have been developed that may be less hazardous to workers than traditional proppants. Pulmonary function testing of workers producing ceramic proppant was used to assess the potential inhalation hazards of ceramic proppant. Male workers (n = 100) from a producer of ceramic proppant were evaluated with pulmonary function test data collected and evaluated using The American Thoracic Society (ATS) acceptability criteria. A comparison group was selected …


Human Health Risk Characterization Of Petroleum Coke Calcining Facility Emissions, Davinderjit Singh Apr 2016

Human Health Risk Characterization Of Petroleum Coke Calcining Facility Emissions, Davinderjit Singh

USF Tampa Graduate Theses and Dissertations

Calcined coke is a high quality carbon material produced by calcining green petroleum coke. Calcining is the process of heating green petroleum coke in a kiln to remove excess moisture, extract all remaining hydrocarbons, and modify the crystalline structure of the coke into a denser, electrically conductive product. The final product, calcined coke, is primarily used to make carbon anodes for the aluminum industry and recarburizing agent for industries such as the steel industry. If not appropriately controlled, the calcining process could lead to excess production of particulate emissions from either handling or storing of raw coke, or from the …


Costumbres, Creencias, Y “Lo Normal”: A Biocultural Study On Changing Prenatal Dietary Practices In A Rural Tourism Community In Costa Rica, Allison Rachel Cantor Apr 2016

Costumbres, Creencias, Y “Lo Normal”: A Biocultural Study On Changing Prenatal Dietary Practices In A Rural Tourism Community In Costa Rica, Allison Rachel Cantor

USF Tampa Graduate Theses and Dissertations

This study explores the relationship between tourism, the nutrition transition, and prenatal dietary practices in the Monteverde Zone, Costa Rica. This rural tourism community, located in the central highlands of Costa Rica, has seen rapid growth and development since the tourism boom in the early 1990s, leading to changes in the local food system and increased food insecurity. This investigation added to this work by identifying the ways that prenatal dietary practices have shifted over time in the context of increased tourism and the concomitant nutrition transition, and by describing the relationship between food insecurity and nutritional status among pregnant …


A Statistical Analysis Of Hurricanes In The Atlantic Basin And Sinkholes In Florida, Joy Marie D'Andrea Apr 2016

A Statistical Analysis Of Hurricanes In The Atlantic Basin And Sinkholes In Florida, Joy Marie D'Andrea

USF Tampa Graduate Theses and Dissertations

Beaches can provide a natural barrier between the ocean and inland communities, ecosystems, and resources. These environments can move and change in response to winds, waves, and currents. When a hurricane occurs, these changes can be rather large and possibly catastrophic. The high waves and storm surge act together to erode beaches and inundate low-lying lands, putting inland communities at risk. There are thousands of buoys in the Atlantic Basin that record and update data to help predict climate conditions in the state of Florida. The data that was compiled and used into a larger data set came from two …


A Quantified Model Of Security Policies, With An Application For Injection-Attack Prevention, Donald James Ray Apr 2016

A Quantified Model Of Security Policies, With An Application For Injection-Attack Prevention, Donald James Ray

USF Tampa Graduate Theses and Dissertations

This dissertation generalizes traditional models of security policies, from specifications of whether programs are secure, to specifications of how secure programs are. This is a generalization from qualitative, black-and-white policies to quantitative, gray policies. Included are generalizations from traditional definitions of safety and liveness policies to definitions of gray-safety and gray-liveness policies. These generalizations preserve key properties of safety and liveness, including that the intersection of safety and liveness is a unique allow-all policy and that every policy can be written as the conjunction of a single safety and a single liveness policy. It is argued that the generalization provides …


The Household Water Management System In The Village Of Falifah, Gambia: A Case Study In Sustainable Local Development, Baboucar Jobe Mar 2016

The Household Water Management System In The Village Of Falifah, Gambia: A Case Study In Sustainable Local Development, Baboucar Jobe

USF Tampa Graduate Theses and Dissertations

Access to safe and clean water is a problem in many countries in the world, especially sub-Saharan Africa. The urgency of the was recognized by the United Nations through its 2008 Millennium Development Goals, which were recently replaced by the new Sustainable Development Goals. Lack or poor access to clean water not only creates conflicts and rifts among the people, but also makes them more susceptible to a wide assortment of water borne diseases.

The purpose of this dissertation is to complete a pilot study of ways of thinking and actions of a small group of people from Falifah, a …


Structure-Interaction Effects In Novel Nanostructured Materials, Nam B. Le Mar 2016

Structure-Interaction Effects In Novel Nanostructured Materials, Nam B. Le

USF Tampa Graduate Theses and Dissertations

Recent advances in experimental and computational methods have opened up new directions in graphene fundamental studies. In addition to understanding the basic properties of this material and its quasi-one dimensional structures, significant efforts are devoted to describing their long ranged dispersive interactions. Other two-dimensional materials, such as silicene, germanene, and transition metal dichalcogenides, are also being investigated aiming at finding complementary to graphene systems with other "wonder" properties. The focus of this work is to utilize first principles simulations methods to build our basic knowledge of structure-interaction relations in two-dimensional materials and design their properties. In particular, mechanical folding and …


A New Volcanic Event Recurrence Rate Model And Code For Estimating Uncertainty In Recurrence Rate And Volume Flux Through Time With Selected Examples, James Adams Wilson Mar 2016

A New Volcanic Event Recurrence Rate Model And Code For Estimating Uncertainty In Recurrence Rate And Volume Flux Through Time With Selected Examples, James Adams Wilson

USF Tampa Graduate Theses and Dissertations

Recurrence rate is often used to describe volcanic activity. There are numerous documented ex- amples of non-constant recurrence rate (e.g. Dohrenwend et al., 1984; Condit and Connor, 1996; Cronin et al., 2001; Bebbington and Cronin, 2011; Bevilacqua, 2015), but current techniques for calculating recurrence rate are unable to fully account for temporal changes in recurrence rate. A local–window recurrence rate model, which allows for non-constant recurrence rate, is used to calculate recurrence rate from an age model consisting of estimated ages of volcanic eruption from a Monte Carlo simulation. The Monte Carlo age assignment algorithm utilizes paleomagnetic and stratigraphic information …


Biophysical Investigation Of Amyloid Formation And Their Prion-Like Self-Replication, Mentor Mulaj Mar 2016

Biophysical Investigation Of Amyloid Formation And Their Prion-Like Self-Replication, Mentor Mulaj

USF Tampa Graduate Theses and Dissertations

Growth and deposition of amyloid fibrils, polymers of proteins with a cross beta-sheet structure, are associated with a significant number of human pathologies including Alzheimer’s disease, Parkinson’s disease, prion diseases, type II diabetes, and senile systematic or dialysis-related amyloidoses. The broader objective of my research is to identify the basic mechanisms regulating nucleation and growth of amyloid fibrils. There is increasing evidence that amyloid formation may proceed along at least two distinct assembly pathways for the formation of rigid fibrils. One pathway involves the nucleated polymerization of the characteristic rigid fibrils from partially denatured monomers and the other proceeds via …


Increasing 18f-Fdg Pet/Ct Capabilities In Radiotherapy For Lung And Esophageal Cancer Via Image Feature Analysis, Jasmine Alexandria Oliver Mar 2016

Increasing 18f-Fdg Pet/Ct Capabilities In Radiotherapy For Lung And Esophageal Cancer Via Image Feature Analysis, Jasmine Alexandria Oliver

USF Tampa Graduate Theses and Dissertations

Positron Emission Tomography (PET) is an imaging modality that has become increasingly beneficial in Radiotherapy by improving treatment planning (1). PET reveals tumor volumes that are not well visualized on computed tomography CT or MRI, recognizes metastatic disease, and assesses radiotherapy treatment (1). It also reveals areas of the tumor that are more radiosensitive allowing for dose painting - a non-homogenous dose treatment across the tumor (1). However, PET is not without limitations. The quantitative unit of PET images, the Standardized Uptake Value (SUV), is affected by many factors such as reconstruction algorithm, patient weight, and tracer uptake time (2). …


Novel Techniques In Chemical Ecology To Examine Life Histories In Fishes, Orian Tzadik Mar 2016

Novel Techniques In Chemical Ecology To Examine Life Histories In Fishes, Orian Tzadik

USF Tampa Graduate Theses and Dissertations

Diet and movements in fishes are often logistically challenging to study. Trace element and stable isotope analyses have advanced these fields considerably, but are still constrained by methodological impediments, such as the tendency towards lethal sampling. Studying endangered fishes is particularly challenging as representative samples are difficult to obtain. However, the information gained from such studies is often critical to the recovery of endangered fishes as knowledge of life history attributes has the potential to greatly influence the success of management strategies.

I tested the viability of using fin rays in fishes as a non-lethal approach to study diet and …


Acropora Habitat Evaluation And Restoration Site Selection Using A Species Distribution Modeling Approach, Katherine Wirt Ames Mar 2016

Acropora Habitat Evaluation And Restoration Site Selection Using A Species Distribution Modeling Approach, Katherine Wirt Ames

USF Tampa Graduate Theses and Dissertations

While populations of nearly all stony coral species along the Florida reef tract have exhibited decline, the most notable decline has occurred in the once-dominant acroporid species (Acropora cervicornis, A. palmata). Both species were listed in 2006 as threatened under the Endangered Species Act. This listing, combined with their continued decline, has resulted in large-scale restoration efforts throughout Florida and the Western Caribbean. Currently, there is little to no information regarding spatial prioritization of sites for these restoration efforts. The primary objective of this dissertation was to utilize species distribution modeling, informed by existing data from the …


Modeling And Survival Analysis Of Breast Cancer: A Statistical, Artificial Neural Network, And Decision Tree Approach, Venkateswara Rao Mudunuru Mar 2016

Modeling And Survival Analysis Of Breast Cancer: A Statistical, Artificial Neural Network, And Decision Tree Approach, Venkateswara Rao Mudunuru

USF Tampa Graduate Theses and Dissertations

Survival analysis today is widely implemented in the fields of medical and biological sciences, social sciences, econometrics, and engineering. The basic principle behind the survival analysis implies to a statistical approach designed to take into account the amount of time utilized for a study period, or the study of time between entry into observation and a subsequent event. The event of interest pertains to death and the analysis consists of following the subject until death. Events or outcomes are defined by a transition from one discrete state to another at an instantaneous moment in time. In the recent years, research …


Optimizing Protocols For Carbohydrate Nmr Chemical Shift Computations, Michael Trent Kemp Mar 2016

Optimizing Protocols For Carbohydrate Nmr Chemical Shift Computations, Michael Trent Kemp

USF Tampa Graduate Theses and Dissertations

The spectroscopic analysis of cellulose is experimentally challenging while computationally accessible with recent developments in NMR code. However, prior to using density functional theory to calculate the NMR chemical shifts of cellulose, smaller, sugar-like molecule systems need to be benchmarked against experimental values. The quantum mechanical / molecular mechanical (QM/MM) calculations presented herein utilize six test systems: ethanol, pyridine, pyrrolidine, pyrrole, myo-inositol and scyllo-inositol in conjunction with the reference tetramethylsilane used to scale the calculated isotropic shielding tensors to relative chemical shifts. The effect of solvent on calculated NMR chemical shifts has also been investigated with regard to quantity of …


Adoption Of The Sawyer Water Filter In Peru, Stephanie D. Paredes Mar 2016

Adoption Of The Sawyer Water Filter In Peru, Stephanie D. Paredes

USF Tampa Graduate Theses and Dissertations

In Peru, lack of water, sanitation, and hygiene (WASH) results in 6,600 deaths per year that represents approximately 3.9% of total deaths. Three thousand and nine hundred of these deaths were due to diarrheal diseases (Prüss-Üstün et al., 2008). Systematic reviews suggest that interventions to improve microbial quality of drinking water are successful in reducing diarrheal diseases (Fewtrell et al., 2005; Clasen et al., 2007; Fry et al., 2013). Interventions for household water treatment and safe storage to ensure safe drinking water reduce diarrhea by 31-52% (WHO/UNICEF, 2013).

The SAWYER PointONE filter, a portable and adaptable membrane filtration device as …


Investigating The Determinants Of Recycling Behavior In Youth By Using Theory Of Planned Behavior., Tejaswini Gadiraju Mar 2016

Investigating The Determinants Of Recycling Behavior In Youth By Using Theory Of Planned Behavior., Tejaswini Gadiraju

USF Tampa Graduate Theses and Dissertations

The aim of this study is to understand the determinants that influence the youth recycling behavior intention. In other words, this study wants to know the motivations and barriers behind university students’ recycling behavior. The Theory of Planned Behavior (TPB), which provides a theoretical framework for systematically identifying the determinants of recycling behavior, is the basis for this study. Along with the TPB variables, additional predictor variables (moral norm, past experience, knowledge of how and what to recycle, knowledge of consequences, and inconvenience) that can influence behavior intentions were tested in the study. Online survey was used to collect the …


Conversion Of Landfill Gas To Liquid Hydrocarbon Fuels: Design And Feasibility Study, Ryan Alexander Kent Mar 2016

Conversion Of Landfill Gas To Liquid Hydrocarbon Fuels: Design And Feasibility Study, Ryan Alexander Kent

USF Tampa Graduate Theses and Dissertations

This paper will discuss the conversion of gas produced from biomass into liquid fuel through the combination of naturally occurring processes, which occur in landfills and anaerobic digesters, and a gas-to-liquids (GTL) facility. Landfills and anaerobic digesters produce gases (LFG) that can be converted into syngas via a Tri-reforming process and then synthesized into man-made hydrocarbon mixtures using Fischer-Tropsch synthesis. Further processing allows for the separation into liquid hydrocarbon fuels such as diesel and gasoline, as well as other middle distillate fuels. Conversion of landfill gas into liquid fuels increases their energy density, ease of storage, and open market potential …


Generalized Phase Retrieval: Isometries In Vector Spaces, Josiah Park Mar 2016

Generalized Phase Retrieval: Isometries In Vector Spaces, Josiah Park

USF Tampa Graduate Theses and Dissertations

In this thesis we generalize the problem of phase retrieval of vector to that of multi-vector. The identification of the multi-vector is done up to some special classes of isometries in the space. We give some upper and lower estimates on the minimal number of multi-linear operators needed for the retrieval. The results are preliminary and far from sharp.


A Study On The Effect Of Non – Asthmatic Atopy On Pregnancy Outcomes, Ayesha Johnson Mar 2016

A Study On The Effect Of Non – Asthmatic Atopy On Pregnancy Outcomes, Ayesha Johnson

USF Tampa Graduate Theses and Dissertations

Objectives – To measure the effect of non – asthmatic atopy (NAA) on the risk of adverse pregnancy outcomes; low birth weight (LBW), small for gestational age (SGA) and preterm birth (PTB), among primiparous women 19 – 25 years of age.

Methods – Vital Statistics records from births occurring between 2004 and 2014, from approximately 60,000 primiparous women in South Carolina, aged 19 to 25 years, were linked to their Medicaid records. Maternal records were examined to determine if they had a previous diagnosis of NAA. Women with a diagnosis of NAA were frequency matched with a ratio of 1:4 …


Resonant Solutions To (3+1)-Dimensional Bilinear Differential Equations, Yue Sun Mar 2016

Resonant Solutions To (3+1)-Dimensional Bilinear Differential Equations, Yue Sun

USF Tampa Graduate Theses and Dissertations

In this thesis, we attempt to obtain a class of generalized bilinear differential equations in (3+1)-dimensions by Dp-operators with p = 5, which have resonant solutions. We construct resonant solutions by using the linear superposition principle and parameterizations of wave numbers and frequencies. We test different values of p in Maple computations, and generate three classes of generalized bilinear differential equations and their resonant solutions when p = 5.


Comparison Of Urinary Pahs Among Firefighters And Asphalt Pavers, Theodore Aquino Mar 2016

Comparison Of Urinary Pahs Among Firefighters And Asphalt Pavers, Theodore Aquino

USF Tampa Graduate Theses and Dissertations

Firefighters and asphalt pavers are exposed to polycyclic aromatic hydrocarbons (PAHs) during various work activities. The purpose of this study was to evaluate urinary PAH levels and compare these bio-monitoring levels among firefighters, asphalt pavers, and non-occupationally exposed individuals. The National Institute of Standards and Technology (NIST) urinary PAH levels were used for non-occupationally exposed controls. When compared to the NIST standard for smokers and non-smokers, firefighters demonstrated statistically significant differences in urinary concentration differences for the following metabolites: 2-OH-fluorene, 3-OH-fluorene and 1-OH-pyrene, which were lower in firefighters than the NIST mean for smokers. 1-OH-phenanthrene, 2-OH-phenanthrene and 3-OH-phenanthrene were higher …


Water Metering In Rural, Piped, Community-Managed Water Systems In The Developing World, Simona Platukyte Mar 2016

Water Metering In Rural, Piped, Community-Managed Water Systems In The Developing World, Simona Platukyte

USF Tampa Graduate Theses and Dissertations

In the early 1990s, the United Nations (UN) recognized water as a finite resource to the entire ecosystem with an economic value that should be developed and managed based on the participatory approach using the Integrated Water Resource Management (IWRM) strategy. Many studies on water management practices have thus emerged in the developing world. Of particular interest to this work is the management of water through metering, price-setting, and rule enforcement in the rural setting in piped, community-owned water systems. There is very little published information regarding metering, enforcement experiments, and experiences in these systems. This is because metering and …