Physical Sciences and Mathematics Commons^™

Electronic Structure Characterization Of Nanocrystalline Surfaces And Interfaces With Photoemission Spectroscopy, Sebastian Gutmann

USF Tampa Graduate Theses and Dissertations

In this study, photoemission spectroscopy (PES) was used to investigate the electronic properties of nanocrystalline titanium dioxide (TiO₂), zinc oxide (ZnO), and cadmium selenide (CdSe). Electrospray deposition technique enabled the preparation of thin films in vacuum from a dispersion prepared outside the vacuum chamber. This method also allowed the step-wise formation of interfaces and the monitoring of the evolution of the electronic structure with intermittent PES characterization.

The work function of nanocrystalline TiO₂ and ZnO was measured with ultraviolet photoemission spectroscopy (UPS) and low-intensity x-ray photoemission spectroscopy (LIXPS). Measurements on environmentally contaminated surfaces revealed an instantaneous and …

Statistical Analysis And Mechanistic Modeling Of Water Quality: Hillsborough Bay, Florida, Keith Hackett

USF Tampa Graduate Theses and Dissertations

Nutrient pollution has been identified as a significant threat to U.S. coastal and estuarine water quality. Though coastal and estuarine waters need nutrients to maintain a healthy, productive ecosystem, excess nutrients can lead to eutrophication. There are significant potential negative consequences associated with eutrophication, including loss of habitat, loss of economic activity, and direct threats to human health. Hillsborough Bay experienced eutrophication in the 1960s and 1970s due to a rapidly growing population and associated increases in nutrient pollution. These eutrophic conditions led to more frequent phytoplankton and macroalgae blooms and declines in seagrasses. To address these problems, a series …

Relative Abundance And Spatial Distribution Of Lepomid Sunfishes In The Peace River, Justin Henry Heller

USF Tampa Graduate Theses and Dissertations

This study examines spatially continuous sampling data in order to investigate patterns of abundance and distribution of three recreationally important sunfish species (bluegill, redear, and spotted sunfish) along the main-stem of the Peace River, a large softwater river located in southwest Florida. A total of 467 electrofishing transects were sampled biannually from spring 2008 to spring 2010. Sampling sites ranged from the headwaters of the Peace River in Polk County, FL to the oligohaline waters located in Charlotte County, FL. All fish were collected with boat mounted electrofishing gear, and aquatic habitat and physiochemical water quality measurements were recorded at …

Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do

USF Tampa Graduate Theses and Dissertations

To date, most studies on the fate and removal of endocrine disrupting compounds (EDCs) and pharmaceutical and personal care products (PPCPs) in wastewater focus on their fate in municipal wastewater treatment plants, and mostly under aerobic condition. There are limited studies related to anaerobic condition and (to our knowledge) no study on the removal of EDCs in landfill leachate by AnMBR. Moreover, for most studies under anaerobic condition, the removal of EDCs was only reported in the liquid phase; solid phase extraction was not reported, thereby preventing mass balance in the studies.

This research was conducted to investigate the potential …

Apparent Total Evaporative Resistance Values From Human Trials Over A Range Of Metabolic And Heat Stress Levels, Matthew David Dooris

USF Tampa Graduate Theses and Dissertations

Failure to maintain thermal equilibrium can cause uncontrollable increases in body core temperature beyond critical upper limits. In selecting clothing, consideration must be given to the heat transfer properties of clothing that may restrict the cooling capacity of the human body under heat stress conditions, most importantly, apparent total evaporative resistance (R_e,T,_a). This study calculated and compared R_e,T,_a for five clothing ensembles under varying heat stress conditions, including three relative humidity (RH) levels and three stages of heat stress to determine if R_e,T,_a values varied or remained the same with …

Population Biology, Ecology, And Ecosystem Contributions Of The Eastern Oyster (Crassostrea Virginica) From Natural And Artificial Habitats In Tampa Bay, Florida, Michael Drexler

USF Tampa Graduate Theses and Dissertations

The objective of this project was to document the status of oysters, Crassostrea virginica, from non-reef habitats throughout Tampa Bay, Florida, and assess the ecosystem contributions of those populations relative to reef-dwelling oysters. The aspects of oyster ecology studied here include condition, prevalence and intensity of disease (Perkinsus marinus - dermo), reproductive activity (including stage, fecundity, and juvenile recruitment), adult oyster density, and the faunal community associated with the oysters.

The predominant source of variation was seasonal, with lesser contributions among sites, and in most cases, little or no effect of the habitat type. Oysters populations from each habitat …

Learning Rules From Incomplete Examples Via Implicit Mention Models, J. Walker Orr, Janardhan Rao Doppa, Mohammed Shahed Sorower, Mohammed Nasresfahani, Jed Irvine, Thomas Dietterich, Prasad Tadepalli

Faculty Publications - Department of Electrical Engineering and Computer Science

We study the problem of learning general rules from concrete facts extracted from natural data sources such as the newspaper stories and medical histories. Natural data sources present two challenges to automated learning, namely, radical incompleteness and systematic bias. In this paper, we propose an approach that combines simultaneous learning of multiple predictive rules with differential scoring of evidence which adapts to a presumed model of data generation. Learning multiple predicates simultaneously mitigates the problem of radical incompleteness, while the differential scoring would help reduce the effects of systematic bias. We evaluate our approach empirically on both textual and non-textual …

Relative Pricing Of Publicly Traded U.S. Electric Utility Companies, Nicholas Stephen Jewczyn

Walden Dissertations and Doctoral Studies

In the financial turmoil of 2008, U.S. firms reported debt-ratios that differed from the debt-ratios calculated from balance sheets. The problem is that investors bought common stock expecting initial investment return and lost money when companies delisted. The purpose of this quantitative study was to determine sample securities pricing with the application of synthetic assets and debt accrued. Addressed in the research questions was whether those securities were (a) underpriced compared with return-on-assets (ROA), (b) overpriced compared with ROA, (c) a debt-ratio higher than 60% and also overpriced, (d) underpriced with a synthetic asset added, or (e) related by relative …

Developing A Master Data Sharing Agreement: Seeking Student-Level Evidence To Support A Collaborative Community Effort In Education, Neil E. Carlson, Edwin Hernández, Chaná Edmond-Verley, Gustavo Rotondaro

University Faculty Publications and Creative Works

The authors, who represent a family foundation, a college, a university, and a public school system, describe the process of developing an agreement that allows student-level data to be shared for research and evaluation purposes. Keys to reaching the agreement included clear distinctions among roles and access to data, strict adherence to consent and confidentiality agreements, and a shared commitment to using data to improve student outcomes.

Meridional Shifts In The Marine Itcz And The Tropical Hydrologic Cycle Over The Last Three Glacial Cycles, Matthew W. Schmidt, Howard J. Spero

OES Faculty Publications

Paleoproxy studies show a strong correlation between tropical climate and high-latitude temperature variability recorded in the Greenland ice cores over the last glacial cycle. In particular, abrupt cooling events in the Greenland Ice Sheet Project II δ¹⁸O ice record appear synchronous with a southward migration of the Intertropical Convergence Zone (ITCZ) in the Atlantic, a weakening of the Indian and East Asian monsoon systems, and a strengthening of the South American monsoon system. Because this high-to-low-latitude climate teleconnection significantly alters the tropical hydrologic cycle around the globe, it plays a critical role in regulating global climate on glacial-interglacial …

A C0 Interior Penalty Method For The Von Kármán Equations, Armin Karl Reiser

LSU Doctoral Dissertations

In this dissertation we develop a C⁰ interior penalty method for the von Kármán equations for nonlinear elastic plates. We begin with a brief survey on frequently used finite element methods for the von Kármán equations. After addressing some topics from functional analysis in the preliminaries, we present existence, uniqueness and regularity results for the solutions of the von Kármán equations in Chapter 3. In the next chapter we review the C⁰ interior penalty method for the biharmonic problem. Motivated by these results, we propose a C⁰ interior penalty method for the linearized von Kármán equations in …

A New Theory Of Stochastic Integration, Anuwat Sae-Tang

LSU Doctoral Dissertations

In this dissertation, we focus mainly on the further study of the new stochastic integral introduced by Ayed and Kuo in 2008. Several properties of this new stochastic integral are obtained. We first introduce the concept of near-martingale for non-adapted stochastic processes. This concept is a generalization of the martingale property for adapted stochastic processes in the It\^o theory. We prove a special case of It\^o isometry for the stochastic integral of certain instantly independent processes. We obtain some formulas for expressing a new stochastic integral in terms of It\^o integrals and Riemann integrals. Several generalized versions of It\^o's formula …

Spatial Ecology Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Louisiana Coastal Waters, Jody Lynn Callihan

LSU Doctoral Dissertations

Spotted seatrout, Cynoscion nebulosus, are common in estuaries and coastal waters of the south Atlantic and Gulf of Mexico and are of considerable recreational and economic importance. Still, the spatial ecology of this species is under-studied and poorly resolved, especially in Louisiana waters. To address this important knowledge gap, I examined the movements, distribution, and habitat use of adult spotted seatrout in coastal Louisiana primarily using high-resolution acoustic telemetry and secondarily, conventional tagging (mark-recapture) data. At the largest spatial scale investigated, I found that adults exhibited a high degree of estuarine fidelity and rarely undertook large-scale movements in excess of …

Sensor-Based Autonomous Pipeline Monitoring Robotic System, Jong-Hoon Kim

LSU Doctoral Dissertations

The field of robotics applications continues to advance. This dissertation addresses the computational challenges of robotic applications and translations of actions using sensors. One of the most challenging fields for robotics applications is pipeline-based applications which have become an indispensable part of life. Proactive monitoring and frequent inspections are critical in maintaining pipeline health. However, these tasks are highly expensive using traditional maintenance systems, knowing that pipeline systems can be largely deployed in an inaccessible and hazardous environment. Thus, we propose a novel cost effective, scalable, customizable, and autonomous sensor-based robotic system, called SPRAM System (Sensor-based Autonomous Pipeline Monitoring Robotic …

Exotic Ground States: A Study In The Structural Effects On Frustration And Dimensionality, Melissa C. Menard

LSU Doctoral Dissertations

Structural disorder and dimensionality play central roles in the characterization of structure and properties of crystalline materials. Although structural disorder is commonly considered an undesirable quality, structural disorder may be desirable when searching for new materials with exotic properties. Disorder can be used as a tunable parameter when considering atomic sizes, coordination preferences, and electronegativity differences can be varied by substituting elements into a given structure. Dimensionality can be viewed as another adjustable parameter when searching for new materials presenting unique challenges when characterizing new materials. One way to tune dimensionality is by chemical doping to affect coupling between layers/chains. …

Fragmentation Sensitivity And Its Consequences On Demography And Host-Ectoparasite Dynamics In Amazonian Birds, Erik I. Johnson

LSU Doctoral Dissertations

The Amazon rainforest is experiencing rapid deforestation due to ranching, agriculture, and urban development, which often leads to remnant patches serving as refugia for forest organisms. By mist-netting passerines in 11 forest fragments (1-, 10-, and 100-ha patches) and nearby continuous forest at the Biological Dynamics of Forest Fragmentation Project near Manaus, Brazil, I conducted a series of studies to identify mechanisms that drive population changes in fragmented landscapes. First, I examined the age structure of bird populations from six ecological guilds in fragments and continuous forest. Immatures are the dispersing age group in birds, and their relative abundance in …

Sol-Gel Resorcinarene Sorbent For Capillary Microextraction Coupled To Gas Chromatography, Abdullah Awadh Alhendal

USF Tampa Graduate Theses and Dissertations

For the first time, octahydroxyl methylresorcinarene with four hexyl groups on the lower rim was utilized in the in-situ preparation of a silica-based sol-gel organicinorganic hybrid coating for sample preconcentration by capillary microextraction (CME). Tetraethoxysilane (TEOS) was chosen as a sol-gel precursor to create a crosslinked sol-gel network via acid-catalyzed hydrolytic polycondensation reactions. Sol-gel chemistry helped in the in situ preparation of resorcinarene-containing extraction phase in the form of a surface coating. It also provided an effective means to chemically bind the coating to the inner surface of fused silica capillary via condensation of the hydroxyl groups in the sol-gel …

Synthesis And Characterization Of Self-Healing Poly (Carbonate Urethane) Carbon-Nanotube Composites, Roger Wesley Bass

USF Tampa Graduate Theses and Dissertations

Synthesis of high molar mass polycarbonate polyurethanes using a novel polyol is described. The resulting elastomers demonstrate excellent mechanical properties as well as the capability to re-heal after rupture without the addition of additives or imbedded healing agents. The self-healing functionality is shown to greatly improve with the addition of up to 1% single and multi-walled carbon nanotubes. The interface of the carbon nanotubes and self-healing polymer are probed using Raman techniques and provide an insight into how the self-healing actions are improved with the addition of carbon nanotubes.

Synthesis of polycarbonate polyurethanes and carbon nanotube composites using a novel …

Stable Isotope Studies Of Paleoenvironment And Paleoclimate From Afar, Ethiopia, Zelalem K. Bedaso

USF Tampa Graduate Theses and Dissertations

The sedimentary deposits of the Hadar Formation at Dikika and the Mount Galili Formation at Galili preserve a wealth of paleoenvironmental and paleoclimatic records spanning the last 5.29 Ma. Stable carbon and oxygen isotopic compositions of herbivore tooth enamel were analyzed for more than 600 specimens of 15 different taxa from 10 stratigraphic intervals. The application of carbon and oxygen isotopes here aims principally at reconstructing shifts in the relative abundance of C₄ grasses, and its implications for climate indicators including temperature, aridity, and seasonality. The full range of δ¹³C_enamel values throughout the Plio-Pleistocene signifies a …

Assessment Of A Countywide Stormwater Pond Improvement Project: Impacts Of The Hillsborough County Adopt-A-Pond Program, Anthony Thomas Betts

USF Tampa Graduate Theses and Dissertations

Comparative research was conducted to assess the environmental impacts of the Adopt-a-Pond program, which operates throughout Hillsborough County, Florida. The Adopt-a-Pond program was established in 1992 and designed to address nonpoint pollution through outreach and stormwater pond enhancement. However, the program had never been thoroughly and scientifically evaluated. Therefore, assessments of water quality and vegetative characteristics were made at ninety Adopt-a-Pond participants and eleven control ponds to explore the potential impacts of the program on measurable environmental parameters. Statistical analysis of the results failed to demonstrate any statistically significant environmental improvements associated with the Adopt-a-Pond program, and measures of program …

First Year Sedimentological Characteristics And Morphological Evolution Of An Artificial Berm At Fort Myers Beach, Florida, Katherine Brutsche

USF Tampa Graduate Theses and Dissertations

Dredging is often conducted to maintain authorized depths in coastal navigation channels. Placement of dredged sediment in the form of nearshore berms is becoming an increasingly popular option for disposal. Compared to direct beach placement, nearshore berms have fewer environmental impacts such as shore birds and turtle nesting, and have more lenient sediment compatibility restrictions. Understanding the potential morphological and sedimentological evolution is crucial to the design of a nearshore berm. Furthermore, the artificial perturbation generated by the berm installation provides a unique opportunity to understand the equilibrium process of coastal morphodynamics.

Matanzas Pass and Bowditch Point, located on the …

A Modeling Analysis Of Dissolved Carbon Dioxide Discharged From Howard F. Curren Advanced Wastewater Treatment Plant, Dustin Capps

USF Tampa Graduate Theses and Dissertations

Currently, the US Environmental Protection Agency primarily regulates the discharge of dissolved nitrogen and phosphorous from wastewater treatment plants in the United States. A recent study has shown that the treated effluent of many plants contains concentrations of dissolved carbon dioxide well above the expected theoretical equilibrium concentration of 0.6 mg/L, indicating that carbon dioxide may have been overlooked as a possible pollutant in receiving waters. For this reason, it is necessary to examine the possible presence of a discharge plume containing high levels of dissolved CO2 downstream from the outfall of a major wastewater treatment plant in Tampa, Florida. …

Novel Magnetic Materials For Sensing And Cooling Applications, Anurag Chaturvedi

USF Tampa Graduate Theses and Dissertations

The overall goals of the present PhD research are to explore the giant magnetoimpedance (GMI) and giant magnetocaloric (GMC) effects in functional magnetic materials and provide guidance on the optimization of the material properties for use in advanced magnetic sensor and refrigeration applications.

GMI has attracted growing interest due to its promising applications in high-performance magnetic sensors. Research in this field is focused on the development of new materials with properties appropriate for practical GMI sensor applications. In this project, we have successfully set up a new magneto-impedance measurement system in the Functional Materials Laboratory at USF. We have established, …

Geochemical Systematics Among Amphibolitic Rocks In The Central Blue Ridge Province Of Southwestern North Carolina, Nathan Collins

USF Tampa Graduate Theses and Dissertations

The Central Blue Ridge sub-province of the southern Appalachian Mountains preserves an unique and complex geologic history. The Cartoogechaye terrane is the westernmost terrane of the Central Blue Ridge sub-province, and is characterized by extensive olistostromal sequences, including mafic-ultramafic massifs, isolated mafic units, and block-in-matrix structures of varying scales. This study investigates the genetic and tectonic relationships, and regional chemical and metamorphic trends of the amphibolitic rocks entrained within units of the Cartoogechaye and nearby terranes, toward constraining the origins of these regional sequences, and examining the rationale for the current Blue Ridge terrane designations.

A distinct compositional variation exists …

Analytical Methods To Support Risk Identification And Analysis In Healthcare Systems, Laila Nadime Cure Vellojin

USF Tampa Graduate Theses and Dissertations

Healthcare systems require continuous monitoring of risk to prevent adverse events. Risk analysis is a time consuming activity that depends on the background of analysts and available data. Patient safety data is often incomplete and biased. This research proposes systematic approaches to monitor risk in healthcare using available patient safety data. The methodologies combine traditional healthcare risk analysis methods with safety theory concepts, in an innovative manner, to allocate available evidence to potential risk sources throughout the system. We propose the use of data mining to analyze near-miss reports and guide the identification of risk sources. In addition, we propose …

Guanidines, Amidines And Carbamides As Novel Sigma Receptor Ligands For Post-Stroke Therapeutics, Michelle Yolanda Cortes-Salva

USF Tampa Graduate Theses and Dissertations

Stroke is the 3^rd leading cause of death in the United States. For this reason, it has become our goal to find a drug that is capable of reestablishing intracellular and extracellular Ca⁺² flux upon direct binding to the sigma receptor, which can be delivered easily and efficiently. Our active research focuses the development of guanidine analogues that can serve as therapeutic drugs which target sigma 1 and sigma 2 receptors having a direct effect on Ca⁺² levels on the cell. The use of symmetrical guanidine analogues such as N,N'-di-o-tolyl guanidine (o-DTG) as therapeutic drugs for ischemic …

Lead Discovery And Optimization Strategies Towards The Development Of 4(1h)-Quinolones And 1,2,3,4-Tetrahydroacridone Analogs With Antimalarial Activity, Richard Matthew Cross

USF Tampa Graduate Theses and Dissertations

The goal of our research endeavor was to successfully employ modern lead discovery and optimization strategies towards the development and identification of compounds possessing antimalarial activity. Preliminary data from in vitro screening at the Walter Reed Army Institute of Research identified several chemotypes including 4(1H)-quinolones and 1,2,3,4-tetrahydroacridones to have potent antimalarial activities. Multiple synthetic routes were devised and implemented which enabled the rapid preparation and isolation of over 400 structurally diverse 4(1H)-quinolones and 1,2,3,4-tetrahydroacridones.

Our research towards discovering and optimizing antimalarials was inspired from the severe impact malaria has had on our planet especially on impoverished countries. There are over …

Microbial Landscapes Of Corals And Ctenophores, Camille Arian Daniels

USF Tampa Graduate Theses and Dissertations

As technology and engineering allow mankind to survey nature at finer scales, the importance of bacteria has been elucidated in their metabolic diversity, ability to transfer genetic information, involvement in biogeochemical cycling, and sheer abundance. With an individual domain of life unto themselves, this diverse group of microorganisms plays an integral role in facilitating life on land and in the oceans, and is second only to viruses in abundance on Earth. They carve niches in a wide range of environments, including those inhospitable to other life forms, and reside in concert or to the detriment of other microbes and/or hosts …

Geriatric Experience Following Cardiac Arrest At Six Interventional Cardiology Centers In The United States 2007-2011, David B. Seder Md, Nainesh Patel Md, John A. Mcpherson Md, Paul W. Mcmullan Md, Karl B. Kern Md, Barbara T. Unger Rn, J Browning, Sudip Nanda Md, Facp, Melkon Hacobian Md, Michael B. Kelley Md, Niklas Nielsen Md, Phd, Michael R. Mooney Md

Department of Medicine

No abstract provided.

Observed Change In Sahel Rainfall, Circulations, African Easterly Waves, And Atlantic Hurricanes Since 1979, Shih-Yu (Simon) Wang, Robert R. Gillies

Plants, Soils, and Climate Faculty Publications

Here, we examine the dynamic properties associated with the recent increase in the Sahel rainfall using an ensemble of five global reanalysis datasets (1979–2010). The rainfall that has been observed to be increasing over the Sahel is accounted for by enhancements in both the tropical easterly jet and the African easterly jet, both of which are known to induce wet anomalies. Moreover, positional shifts in the African easterly jet and African easterly waves (AEWs) accompanied the northward migration of the Sahel rainband. Change in the African easterly jet and AEWs are coupled to a northward shift and amplification of convective …