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Measurement Of Dissolved Gas Concentrations In Natural Waters Utilizing An In-Situ, Membrane Inlet, Linear Quadrupole Mass Spectrometer, Peter Wenner

USF Tampa Graduate Theses and Dissertations

Since its creation in the late 19th century, mass spectrometry has evolved into one of the most versatile analytical methods in science. To chart this evolution this thesis includes a historical overview of mass spectrometry and a description of the role of mass spectrometry in oceanography. The development and deployment of underwater mass spectrometers (UMS) at the University of South Florida's Center for Ocean Technology has made possible the collection of real-time data with greatly increased spatial and temporal density. The UMS was deployed via both remotely guided surface vehicles (GSV) and ship's cables to monitor a suite of dissolved …

Spatial And Temporal Trends In Water Quality In The Alafia River Watershed, Jennifer M. Aragon

USF Tampa Graduate Theses and Dissertations

Water quality data and land use information were analyzed within the Alafia River watershed in Florida to determine spatial and temporal trends in these variables over a 16 year time period from 1991-2006. Monthly water quality data (for dissolved oxygen, turbidity, fecal coliform, total phosphorus, and total nitrogen) were statistically analyzed using the modified seasonal Kendall nonparametric test for trends that accounts for serial correlation. The statistical trend analysis was conducted for the entire study period, but monthly, seasonal, and land use trends were also examined. Land use information was examined using Geographic Information Systems to determine the percent change …

Pegylation Of Niosomes, John A. Elliott

USF Tampa Graduate Theses and Dissertations

The research presented in this dissertation describes the creation and characterization of a novel antibody-vesicle conjugate modified with polyethylene glycol (PEG) that possesses enhanced binding to and uptake by inflammation-activated endothelial cells with improved storage stability and longer shelf-life and potential reduction in immunogenic potential compared to previous designs.

Targeted drug delivery provides an effective means of delivering therapeutic concentrations of a drug to the site or organ of action. The drug is delivered using a niosome, a vesicle with an aqueous core and a bilayer membrane composed of non-ionic surfactants and cholesterol. Antibodies that recognize specific cell antigens are …

Workin’ From Cain To Cain’T: Challenges Within Florida’S Gulf Coast Oyster Industry, Diane Marie Wakeman

USF Tampa Graduate Theses and Dissertations

Oyster tongers are a cultural icon of Florida's maritime heritage and geography. Challenged for generations by the vagaries of weather, including catastrophic storms and years-long droughts, and economic uncertainties this maritime heritage is fading fast. While Florida's north and west coasts produce 90 percent of the Florida oyster harvest and ten percent of oysters consumed in the United States, the industry is at risk today for reasons including a declining demand for Florida oysters because of health concerns; water pollution; population growth and its accompanying development of condominiums, gated communities, and retail shopping centers; and declining interest in the hard …

Creek/Seminole Archaeology In The Apalachicola River Valley, Northwest Florida, April J. Buffington

USF Tampa Graduate Theses and Dissertations

The Seminole Indians were Creek Indians from Georgia and Alabama who migrated to Florida for several reasons, including much conflict from not only other native groups but European pursuits. This thesis documents the early Creeks coming into northwest Florida, and thereby contributes to the larger research question of Seminole ethnogenesis. By compiling not only the confusing and often unclear historical documentation, but also the archaeological record, this thesis examines Creek/Seminole archaeological sites along the Apalachicola River and lower Chattahoochee River and matches them up with known historical towns to see where and when the Creek Indians were coming into Florida …

Memory - Ness: The Collaboration Between A Library And Museum, Kelsey Doughty

USF Tampa Graduate Theses and Dissertations

Picture a historical library and a historical art museum coming together to challenge the interaction between each other to help experience, explore, and discover the past within the present. While it sounds like a good idea, it is rare to see a library and museum under one roof.

With the increasing population of tourists looking to visit places and buildings that reconnect with history, there is a higher demand for places to be able to 're-live the past' through art and literature. People enjoy visiting places where history was made and where it becomes part of a city's identity. With …

Designing Community: The Application Of New Urban Principles To Create Authentic Communities, Margaret Embry

USF Tampa Graduate Theses and Dissertations

This research is an exploratory investigation of the potential of New Urbanist planning and design principles to create thriving and successful neighborhoods. New Urbanism is an urban design movement started in the early 1980s that promotes the development of walkable, compact, and diverse neighborhoods. It is the objective of this research to shed light on the value of creating a higher quality of life and more time for ourselves and our families. I hypothesize that New Urbanism may pave the way for recapturing commute time for time with family, creating authentic and successful communities, and engaging with neighbors. Furthermore, by …

Development And Deployment Of An Underwater Mass Spectrometer For Quantitative Measurements Of Dissolved Gases, Ryan J. Bell

USF Tampa Graduate Theses and Dissertations

Manual collection and processing of seawater samples for dissolved gas analyses are technically challenging, time consuming and costly. Accordingly, in situ analysis techniques present attractive alternatives to conventional gas measurement procedures. To meet the demands of sustained, high-resolution chemical observations of the oceans, the University of South Florida and SRI International developed underwater mass spectrometer systems for quantitative measurements of dissolved gases and volatile organic compounds. This work describes the influence of variable in situ conditions on the performance of a membrane introduction mass spectrometer used for measurements in both the water column and sediment porewater.

Laboratory experiments to simulate …

Theory And Simulation Of Metal-Organic Materials And Biomolecules, Jonathan L. Belof

USF Tampa Graduate Theses and Dissertations

The emerging field of nanomaterials has raised a number of fascinating scientific questions that remain unanswered. Molecular theory and computer simulation are key tools to unlocking future discoveries in materials science, and various computational techniques and results toward this goal are elucidated here. High-performance computing methods (utilizing the latest supercomputers and codes) have been developed to explore and predict the chemistry and physical properties of systems as diverse as Metal-Organic Frameworks, discrete nanocubes, photoswitch molecules, porphyrins and several interesting enzymes. In addition, highlights of fundamental statistical physics, such as the Feynman-Hibbs effective partition function and generalized ensemble theory, are expounded …

The Role Of Cocrystals In Solid-State Synthesis Of Imides And The Development Of Novel Crystalline Forms Of Active Pharmaceutical Ingredients, Miranda L. Cheney

USF Tampa Graduate Theses and Dissertations

With a greater understanding of the fundamentals of crystal engineering lays the

potential for the development of a vast array of novel materials for a plethora of

applications. Addressed herein is the latent potential of the current knowledge base with

an emphasis upon cocrystallization and the desire for scientific exploration that will lead

to the development of a future generation of novel cocrystals. The focus of this

dissertation is to expand the cocrystallization knowledge base in two directions with the

utilization of cocrystals in the novel synthetic technique of cocrystal controlled solid-state

synthesis and in the development of active pharmaceutical …

Tracing Anthropogenic Wastes: Detection Of Fluorescent Optical Brighteners In A Gradient Of Natural Organic Matter Fluorescence, Laura Kellie Dixon

USF Tampa Graduate Theses and Dissertations

A dual wavelength method was developed for the field detection of optical brighteners

(OBs), fluorescent laundry additives used as indicators of anthropogenic wastes. The

method was quantitative for OBs under variable levels of fluorescent colored dissolved

organic matter (CDOM). Based on excitation at 300-400 nm and 440 and 550 nm

emission, the method assumed a constant ratio of fluorescence due to CDOM alone, even

if absolute amplitude varied. Concentrations of OBs were computed as the difference

between the observed 440 nm emission and the expected CDOM fluorescence at 440 nm,

as extrapolated from the 550 nm fluorescence and established CDOM …

Investigation Of The Factors Influencing Skid Resistance And The International Friction Index, Luis G. Fuentes

USF Tampa Graduate Theses and Dissertations

This dissertation is compiled of the findings of several phases of a detailed research study that was aimed at investigating the Skid Resistance phenomenon. In the first phase of the dissertation research a study was performed to evaluate the different factors that influence frictional measurements obtained using the Dynamic Friction Tester (DFT). A temperature calibration factor that would account for temperature effects on DFT readings and IFI computations was developed. In addition, other variables that also affect the friction measurements obtained using the DFT are identified. In the next phase of the dissertation research the effect of pavement roughness on …

From China To Cuba: Guerilla Warfare As A Mechanism For Mobilizing Resources, Jorge Barrera

USF Tampa Graduate Theses and Dissertations

Guerilla Warfare is a weapon of the weak; it is decisive only where the actor in power fails to commit adequate resources to the conflict. The Chinese and Cuban revolutions are examples of guerilla warfare success, albeit under different conditions and employment techniques; while Mao Tse-tung utilized decentralized guerilla warfare to indoctrinate and mobilize the masses of peasants for revolutionary struggle against a stronger enemy; Fidel Castro employed a more centralized approach to create the conditions necessary for popular support of the revolution. However, in both cases guerilla warfare was simply part of a pragmatic grand strategy to build nationalism …

Globalization, Migration And The U.S. Labor Market For Physicians: The Impact Of Immigration On Local Wages, Finnie B. Cook

USF Tampa Graduate Theses and Dissertations

The healthcare labor market has experienced some significant changes in the last half century, including the establishment of Medicare and Medicaid in 1965, the emergence of managed care in the 1980s, and the worldwide mobility of labor encouraged by globalization. Currently, more than 25% of physicians working in the U.S. are foreign-born. The existing body of literature related to the impact of immigration on local wages has to date found conflicting results. The purpose of this research is to evaluate the impact of immigration of foreign physicians on local physician wages. This study employs physician survey data from the AMA …

Task Oriented Simulation And Control Of A Wheelchair Mounted Robotic Arm, Fabian Farelo

USF Tampa Graduate Theses and Dissertations

The main objective of my research is to improve the control structure for the new Wheelchair Mounted Robotic Arm (WMRA) to include new algorithms for optimized task execution; that is, making the WMRA a modular task oriented mobile manipulator. The main criterion to be optimized is the fashion in which the wheelchair approaches a final target as well as the starting and final orientation of the wheelchair. This is a novel approach in non-holonomic wheeled manipulators that will help in autonomously executing complex activities of daily living (ADL) tasks.

The WMRA is a 9 degree of freedom system, which provides …

Sensitivity Analysis Of Three Assembly Procedures For A Bascule Bridge Fulcrum, Luke Allen Snyder

USF Tampa Graduate Theses and Dissertations

Many different hub assembly procedures have been utilized over the years in bascule bridge construction. The first assembly procedure (AP1) involves shrink fitting a trunnion component into a hub, followed by the shrink fitting of the entire trunnion-hub (TH) assembly into the girder of the bridge. The second assembly procedure (AP2) involves shrink fitting the hub component first into the girder, then shrink fitting the trunnion component into the hub-girder (HG) assembly. The final assembly procedure uses a warm shrink fitting process whereby induction coils are placed on the girder of the bridge and heat is applied until sufficient thermal …

A Computational Kinematics And Evolutionary Approach To Model Molecular Flexibility For Bionanotechnology, Athina N. Brintaki

USF Tampa Graduate Theses and Dissertations

Modeling molecular structures is critical for understanding the principles that govern the behavior of molecules and for facilitating the exploration of potential pharmaceutical drugs and nanoscale designs. Biological molecules are flexible bodies that can adopt many different shapes (or conformations) until they reach a stable molecular state that is usually described by the minimum internal energy. A major challenge in modeling flexible molecules is the exponential explosion in computational complexity as the molecular size increases and many degrees of freedom are considered to represent the molecules' flexibility. This research work proposes a novel generic computational geometric approach called enhanced BioGeoFilter …

Effects Of Geomorphic Setting On Shallow-Groundwater Exchange And Water Temperature Of Salmon-Bearing Headwater Streams Of The Lower Kenai Peninsula, Alaska, Jason C. Bellino

USF Tampa Graduate Theses and Dissertations

Temperature is an important physical characteristic of headwater streams that controls the presence and health of juvenile salmonids. Surface water temperature is controlled by many factors including exchanges with groundwater. A study of the hydrology of wetlands associated with headwater streams on the Lower Kenai Peninsula was conducted to determine the effect of geomorphic setting on groundwater discharge to streams and ultimately on in-stream water temperature. Attention was focused on drainage-way and discharge slope wetlands as two end-members of the geomorphic settings of the study area.

Data were collected at 18 study reaches spanning four major watersheds in the study …

Performance Analysis Of A Binary-Tree-Based Algorithm For Computing Spatial Distance Histograms, Sadhana Sharma Luetel

USF Tampa Graduate Theses and Dissertations

The environment is made up of composition of small particles. Hence, particle simulation is an important tool in many scientific and engineering research fields to simulate the real life processes of the environment. Because of the enormous amount of data in such simulations, data management, storage and processing are very challenging tasks. Spatial Distance Histogram (SDH) is one of the most popular queries being used in this field. In this thesis, we are interested in investigating the performance of improvement of an existing algorithm for computing SDH. The algorithm already being used is using a conceptual data structure called density …

Hemocompatibility Assessment Of 3c-Sic For Cardiovascular Applications, Norelli Schettini

USF Tampa Graduate Theses and Dissertations

The hemocompatibility of crystalline Silicon Carbide (SiC), in its cubic form (i.e., 3C-SiC), has been evaluated and compared to Silicon (Si), the leading material in biosensing applications. Silicon carbide (SiC) is a hard, chemically robust material, very well suited for harsh environment applications, and has been suggested to have very good biocompatibility. Additionally, SiC in its amorphous form, has been used as a coating for medical implantable devices such as bone prosthetics and cardiovascular stents. However, assessment of single crystal 3C-SiC for cardiovascular applications has not been reported. In this research we have studied the interactions of single crystal 3C-SiC …

Fireproofing The Lawn: Reclaimed Water And Polybrominated Diphenyl Ethers In Tampa Bay, Ryan C. Davis

USF Tampa Graduate Theses and Dissertations

Reclaimed water has increased in popularity as a means to recycle water and thus decrease the amount of wasteful water use. This process is widely used in Tampa Bay for watering of lawns. This increase in popularity and use has raised questions as to what contaminants are in the reclaimed water.

The purpose of this study was to analyze reclaimed water for contaminants believed to be detrimental to health and conduct interviews to ascertain perceptions of risk in the local population. As water reuse grows in popularity further research will need to be conducted to address potential human health concerns. …

Investigation Of Residual And Thermal Stress On Membrane-Based Mems Devices, Lynford O. Davis

USF Tampa Graduate Theses and Dissertations

Thin films have become very important in the past years as there is a tremendous increase in the need for small-scale devices. Thin films are preferred because of their electrical, mechanical, chemical, and other unique properties. They are often used for coatings, and in the fabrication of Microelectronic devices and Micro-electro Mechanical Systems (MEMS). Internal (residual) stress always exists when a thin film is employed in the device design. Residual and thermal stresses cause membrane bow, altering the anticipated dynamic response of a membrane-based MEMS design. The device may even become inoperable under the high stresses conditions. As a result, …

Pulsed Power And Load-Pull Measurements For Microwave Transistors, Sivalingam Somasundaram Meena

USF Tampa Graduate Theses and Dissertations

A novel method is shown for fitting and/or validating electro-thermal models using pulsed I(V) measurements and pulsed I(V) simulations demonstrated using modifications of an available non-linear model for an LDMOS (Laterally Diffused Metal Oxide Semiconductor) device. After extracting the thermal time constant, good agreement is achieved between measured and simulated pulsed I(V) results under a wide range of different pulse conditions including DC, very short (<0.1%) duty cycles, and varied pulse widths between these extremes. A pulsed RF load-pull test bench was also assembled and demonstrated for a VDMOS (Vertically Diffused Metal Oxide Semiconductor) and an LDMOS power transistor. The basic technique should also be useful for GaAs and GaN transistors with suitable consideration for the complexity added by trapping mechanisms present in those types of transistors.

Handover Performance In The Mobile Wimax Netrworks, Yongxue Yu

USF Tampa Graduate Theses and Dissertations

Mobile terminals allow users to access service while on the move. This unique feature has driven the rapid growth in the mobile network industry, changing it from a new technology into a massive industry in less than two decades.

In this thesis, an in-depth study of the handover effects of mobile WiMAX networks is carried out. The mobile WiMAX technology is first presented as literature study and then the technologies of handovers for previous generations are introduced in detail. Further, the hard handover of the mobile WiMAX is simulated by Network Simulator-2 (NS-2). In addition, the "ping-pang" effect of handover …

Environment, Channel, And Interference Awareness For Next Generation Wireless Networks, Serhan Yarkan

USF Tampa Graduate Theses and Dissertations

Wireless communication systems have evolved substantially over the last two decades. The explosive growth of the wireless communications market is expected to continue in the future, as the demand for all types of wireless services is increasing. Beside providing higher data rates, next generation wireless networks (NGWN) are expected to have advanced capabilities such as interoperability, efficient spectrum utilization along with a wide variety of applications over different domains (e.g., public safety and military, aeronautical networks, femtocells, and so on) to the mobile users while serving as many users as possible.

However, these advanced capabilities and services must …

Development Of Cdte Thin Film Solar Cells On Flexible Foil Substrates, Deidra Ranel Hodges

USF Tampa Graduate Theses and Dissertations

Cadmium telluride (CdTe) is a leading thin film photovoltaic (PV) material due to its near ideal band gap of 1.45 eV, its high optical absorption coefficient and availability of various device fabrication methods. Superstrate CdTe solar cells fabricated on glass have to-date exhibited efficiencies of 16.5%. Work on substrate devices has been limited due to difficulties associated with the formation of an ohmic back contact with CdTe. The most promising approach used to-date is based on the use of an interlayer between the CdTe and a metal electrode, an approach that is believed to yield a pseudo-ohmic contact. This research …

Architectures And Algorithms For Mitigation Of Soft Errors In Nanoscale Vlsi Circuits, Koustav Bhattacharya

USF Tampa Graduate Theses and Dissertations

The occurrence of transient faults like soft errors in computer circuits poses a significant challenge to the reliability of computer systems. Soft error, which occurs when the energetic neutrons coming from space or the alpha particles arising out of packaging materials hit the transistors, may manifest themselves as a bit flip in the memory element or as a transient glitch generated at any internal node of combinational logic, which may subsequently propagate to and be captured in a latch. Although the problem of soft errors was earlier only a concern for space applications, aggressive technology scaling trends have exacerbated the …

Biomechanical Model Of Transhumeral Prostheses, Rebekah Freilich

USF Tampa Graduate Theses and Dissertations

It has been shown that the interface between the prosthetic socket and residual limb (S-RL) interface is an important factor in determining acceptance and outcomes of upper limb prostheses. [1] Among the most common complaint from amputees is that the prosthesis is uncomfortable due to developing skin irritation which is usually attributed to poor fit (Nielson 1990). In order to understand why skin irritations can and do occur it is imperative to examine the biomechanical properties of the S-RL interface. A primary reason behind the development of skin irritation is instability of the socket upon the residuum. Alley (2009) asserts …

A Data Link Layer In Support Of Swarming Of Autonomous Underwater Vehicles, Daladier Jabba Molinares

USF Tampa Graduate Theses and Dissertations

Communication underwater is challenging because of the inherent characteristics of the media. First, common radio frequency (RF) signals utilized in wireless communications cannot be used under water. RF signals are attenuated in such as way that RF communication underwater is restricted to very few meters. As a result, acoustic-based communication is utilized for underwater communications; however, acoustic communication has its own limitations. For example, the speed of sound is five orders of magnitude lower than the speed of light, meaning that communications under water experience long propagation delays, even in short distances. Long propagation delays impose strong challenges in the …

Development Of Three Dimensional Fluid-Structure Interaction Models For The Design Of Surface Acoustic Wave Devices: Application To Biosensing And Microfluidic Actuation, Reetu Singh

USF Tampa Graduate Theses and Dissertations

Surface acoustic wave (SAW) devices find uses in a plethora of applications including

but not limited to chemical, biological sensing, and microfluidic actuation. The primary aim of

this dissertation is to develop a SAW biosensor, capable of simultaneous detection of target

biomarkers in fluid media at concentrations of picogram/ml to nanogram/ml levels and removal

of non-specific proteins from sensor surface using the process of acoustic streaming, for potential

chemical sensing, medical, and clinical diagnostic applications. The focus is on the development

of three dimensional finite element structural and fluid-structure interaction models to study wave

propagation and acoustic actuation of fluids …