Digital Commons Network^™

Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger

USF Tampa Graduate Theses and Dissertations

The development of an accurate and precise geochronology is imperative to understanding archives containing information about Earth’s past. Unable to date all intervals of an archive, researchers use methods of interpolation to approximate age between dates. Sections of the radiocarbon calibration curve can induce larger chronological uncertainty independent of instrumental precision, meaning even a precise date may carry inflated error in its calibration to a calendar age. Methods of interpolation range from step-wise linear regression to, most recently, Bayesian statistical models. These employ prior knowledge of accumulation rate to provide a more informed interpolation between neighboring dates. This study uses …

Mass-Spectrometry Based Proteomics Of Age-Related Changes In Murine Microglia, Antwoine Flowers

USF Tampa Graduate Theses and Dissertations

The last century has seen a steady increase in the extension of the average lifespan. This has concomitantly produced higher incidences of age-related chronic degenerative diseases like Alzheimer’s and Parkinson’s diseases. Age is the single greatest risk factor for the development of not just these degenerative conditions but cancer as well. The aged niche undergoes a number of maladaptive changes that allow underlying conditions to present and progress. Exactly which changes, contribute to the progression of which disease is currently an area of intense study. However, these answers often present therapeutic targets for disease prevention. Age is characterized by a …

Tradeoffs In Protocol Designs For Collaborative Authentication, Jacob Venne

USF Tampa Graduate Theses and Dissertations

Authentication is a crucial tool used in access control mechanisms to verify a user’s identity. Collaborative Authentication (co-authentication) is a newly proposed authentication scheme designed to improve on traditional token authentication. Co-authentication works by using multiple user devices as tokens to collaborate in a challenge and authenticate a user request on single device.

This thesis adds two contributions to the co-authentication project. First, a detailed survey of applications that are suitable for adopting co-authentication is presented. Second, an analysis of tradeoffs between varying protocol designs of co-authentication is performed to determine whether, and how, any designs are superior to other …

Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder

USF Tampa Graduate Theses and Dissertations

In the past, the Northern Tampa Bay Area (NTBA) wetlands saw severe declines in hydrologic conditions due to excessive groundwater withdrawal rates. Eventually these rates were reduced to allow the wetlands to recover. To monitor this recovery, the Southwest Florida Water Management district (SWFWMD) set up a fieldwork based scoring methodology, called the Wetlands Assessment Procedure (WAP). WAP has been used in many studies of the area since groundwater withdrawal reductions; with many of those studies finding the recovery to be mixed at best. However, these studies were very limited in the number of wetlands they could assess due to …

Sorption Of Benzene, Dichloroethane, Chloroform And Dichloromethane By Polyethylene Glycol, Polycaprolactone And Their Copolymers At 298.15 K Using A Quartz Crystal Microbalance, Abhijeet Radhakrishna Iyer

USF Tampa Graduate Theses and Dissertations

Quartz crystal microbalances (QCM) are acoustic wave sensor systems which are used majorly for vapor and liquid sensing. QCM come under the category of thickness shear mode (TSM) sensors. There are several methods to study organic vapor sensing; the QCM method is the one that offers the highest sensitivity and generates the most data. Solubilities of benzene, dichloroethane, chloroform and dichloromethane in polyethylene glycol (PEG), polycaprolactone (PCL), and several di-block PEG/PCL copolymers at 298.15 K are reported. There are literature data available for most of the solvents in the homopolymers PEG and PCL but no literature data is available for …

Mechanism Of Cathodic Prevention Of Carbon Steel In Concrete, Krittin Rattakham

USF Tampa Graduate Theses and Dissertations

In this work, I aim to clarify the mechanism that allows steel to attain higher chloride threshold as it is cathodically polarized. Specifically, I seek to provide empirical information on whether an intrinsic (predominantly interfacial effects of polarization) or an extrinsic (predominantly concentration changes due to polarization) mechanism may be dominant in the beneficial effect of polarization. I carried out this experiment with 12 identical concrete specimens, each with a cast-in steel plate, constantly exposed them to high-chloride environment. The specimens were divided into 4 triplicates and polarized at 4 different level from OCP, -200, -300 to -400 mV_{SCE …}

Essays On The Tax Policy And Insider Trading, Han Shi

USF Tampa Graduate Theses and Dissertations

In the first essay I examine the relation between firm advertising and tax aggressiveness. Advertising increases firm visibility in both the product and the financial market. While investors would appreciate more tax savings, they are aware of the negative impact of tax aggressiveness on consumers’ views of the firm and hence its competitive positions in the product market. We find that firms that spend more on advertising have fewer tax sheltering activities, lower book-tax differences, and higher cash effective tax rates. Specifically, an increase of 1% on Advertising_i,t (ADVGP_i,t), the firm pays an additional tax of $0.70 …

Back Muscle Endurance As Measure By Ito Test Duration, Ronald Figueredo

USF Tampa Graduate Theses and Dissertations

Lower back pain remains one of the most common problems in public health throughout the industrialized world (Strine and Hootman) (Shiri, Solovieva and K.). The prevalence is about 39-54% annually and 60-65% in a lifetime (Hillman, Wright and Rajaranam) (Leboeuf-Yde, N. and Lauritzen). In the United States, lower back pain is the second most common cause of disability, and is the highest cause of disability among men (Center for Disease Control, 2009). An individual quantitative physical examination to detect muscle deficiencies would be very useful for proper placement of workers in demanding physical jobs where back injuries are common. Trunk …

3d Cave And Ice Block Morphology From Integrated Geophysical Methods: A Case Study At Scărişoara Ice Cave, Romania, Jackson Durain Hubbard

USF Tampa Graduate Theses and Dissertations

Scărişoara Ice Cave has been a catalyst of scientific intrigue and effort for over 150 years. These efforts have revealed and described countless natural phenomena – and in the process have made it one of the most studied caves in the world.

Of especial interest is the massive ice block located within its Great Hall and scientific reservations. The ice block, which is the oldest and largest known to exist in a cave, has been the focus of multiple surveying and mapping efforts, typically ones utilizing traditional equipment. In this study, the goals were to reconstruct the ice block/cave floor …

Development Of Tools For Stable Transfection In The Human Filarial Parasite Brugia Malayi Via The Piggybac Transposon System, Johan Chabanon

USF Tampa Graduate Theses and Dissertations

Brugia malayi is one of three species of nematode known to cause lymphatic filariasis (LF) in humans. LF infects over 120 million people, causing debilitating disease. Various global programs have been launched in the past 20 years to eliminate LF. These programs have greatly scaled up the resources and efforts allocated to halting the transmission and reducing disease burden. Only a few drugs are used to treat LF, and resistance is thus a devastating possibility. Research aimed at identifying new drug targets could therefore prove essential in elimination of LF.

Genetic manipulation of B. malayi has been limited to transient …

Leaders On Their Best Behavior: Leader Behaviors Resulting In Effective Virtual Teams, Sarah Elizabeth Frick

USF Tampa Graduate Theses and Dissertations

A more globalized workforce, coupled with technological advances in electronic communication, have led organizations to turn to virtual work teams at a rapidly increasing rate (Gilson, Maynard, Young, Vartiainen, & Hakonen, 2015). Leadership has been shown to aid team performance across work domains (Morgeson, DeRue, & Karam, 2010), and there exist a host of functional leader behaviors that have been found to benefit face-to-face team performance (Burke, Stagl, Klein, Goodwin, Salas, & Halpin, 2006). Attention to leadership in this new era of work teams is necessary to identify those specific behaviors that enable effective virtual team functioning. Team performance, whether …

Can Selection Tests Administered Via Video Games Reduce Faking?, Philip Scott Ramsay

USF Tampa Graduate Theses and Dissertations

One of the fundamental underlying assumptions of selection procedures is that the information gathered from applicants is accurate, and thus, will predict performance on the job (Donovan, Dwight, & Schneider, 2014; Schmitt & Sinha, 2011). As self-report instruments such as paper-and-pencil tests and unsupervised online surveys become more prevalent in organizational selection contexts (Truxillo & Bauer, 2011) due to ease of use and cost efficiency, the concern of applicants faking responses to inaccurately portray themselves as more highly desirable is increasingly critical (Hough, Oswald, & Ployhart, 2001). Depending on the exact magnitude of the particular selection event, this compromise of …

Taxonomy, Ecology, And Behavior Of The Kleptoplastic Sea Slug Elysia Papillosa, William Alan Gowacki

USF Tampa Graduate Theses and Dissertations

Sacoglossan sea slugs are one of the best known examples of specialist herbivores in the marine environment and can be found strongly associated with their algal hosts and food sources. Perhaps the most intriguing characteristic of many sacoglossans is their ability to sequester functional chloroplasts from their algal food sources in a process called kleptoplasty. Despite this, there continues to be issues regarding taxonomic identification of species. In turn, the ecological characteristics of many of these slugs, such as algal host and food source preference, as well as their behavioral aspects, have received little attention. A prime example of these …

Simulation Studies On Ecg Vector Dipole Extraction In Liquid Medium, Pratheek Michael

USF Tampa Graduate Theses and Dissertations

To circumvent some inherent problems in the conventional ECG, this research reinvestigates an ‘unassisted’ approach which enables ECG measurement without the placement of leads on the body. Employed in this research is a widely accepted assumption that the electrical activity of the heart may be represented, largely, by a 3-D time-varying current dipole (3D-CD). From the PhysioBank database, mECG and fECG data were obtained, and Singular Value Decomposition (SVD) was performed to estimate the time-varying Vector ECG dipole. To determine the sensing matrix responsible for transforming the activity of the 3D-CD into the potential distribution on the surface of the …

Daniel Bryan & The Negotiation Of Kayfabe In Professional Wrestling, Brooks Oglesby

USF Tampa Graduate Theses and Dissertations

This thesis will examine the negotiation of kayfabe within the context of professional wrestling using a 2014 WWE storyline that arose from fan backlash as a primary text. The perceived marginalization of wrestler Daniel Bryan by the fans led to a disconnect between the narratives that were performed in-ring and the counter-narratives produced by the fans, which in turn led to an overtly co-authored narrative between in-ring performers and fans. In addition to studying the television narratives that characterize the “Yes Movement,” in WWE, I will analyze archived social media responses within fan communities on Twitter and Reddit to make …

Characterizing The Evolution Of Slab Inputs In The Earliest Stages Of Subduction: Preliminary Evidence From The Fluid-Mobile Element (B, Cs, As, Li) Systematics Of Izu-Bonin Boninitic Glasses Recovered During Iodp Expedition 352, Keir Aavon Sanatan

USF Tampa Graduate Theses and Dissertations

Fluid-mobile elements (FMEs) such as B, Cs, As, Li and Tl can mobilize readily under low P-T conditions (0.2-0.5 GPa). This makes them effective geochemical tracers that can be used as a way of tracking fluid-rock exchanges at the shallow depths encountered in the earliest stages of subduction.

The Izu-Bonin-Mariana (IBM) subduction system is unique in that it preserves a record of the sequences produced from the onset of subduction through the development of arc magmatism. International Ocean Discovery Program (IODP) Expedition 352 recovered >800m of boninite core material from the earliest IBM magmatic events.

Select boninitic glasses from these …

Latitudinal Position And Trends Of The Intertropical Convergence Zone (Itcz) And Its Relationship With Upwelling In The Southern Caribbean Sea And Global Climate Indices, Kaitlyn E. Colna

USF Tampa Graduate Theses and Dissertations

The Intertropical Convergence Zone (ITCZ) is a feature that results from the ocean-atmosphere interactions in the tropics around the world. The ITCZ is characterized by surface wind convergence, tall storm clouds, and it forms a belt of high time-averaged precipitation around the globe. The ITCZ undergoes seasonal migrations between 5°S and 15°N roughly following the subsolar point on Earth with the seasons, with a mean annual position located slightly above the Equator, between 2° and 5°N.

This study tested the hypothesis that there was a northward shift in the median position of the ITCZ in the first decade of the …

Spatio-Temporal Dynamics Of Soil Composition And Accumulation Rates In Mangrove Wetlands, Joshua L. Breithaupt

USF Tampa Graduate Theses and Dissertations

Coastal wetlands are globally important environments for biogeochemical cycling and are the object of intensive research related to the sequestration and exchange of carbon with oceans, continents, and the atmosphere. Wetland soil core records of organic carbon (OC) provide insights about future ecosystem responses to global change by identifying temporal variability in the context of environmental changes including sea level rise (SLR), anthropogenic reductions in freshwater flow, and landscape-scale disturbance events. My studies of Gulf of Mexico mangroves involved the use of radiometrically-dated soil cores to identify spatial and temporal accumulation trends of various constituents including organic and carbonate carbon, …

A Novel Abi-Domain Protein Controls Virulence Determinant Production In Staphylococcus Aureus, Stephanie Michelle Marroquin

USF Tampa Graduate Theses and Dissertations

A major factor in the success of Staphylococcus aureus as a pathogen is its vast arsenal of virulence determinants and, more importantly, the tight and precisely- timed regulation of these factors. Here we investigate the product of the S. aureus gene, SAUSA300_1984, encoding a putative transmembrane protein. This as yet uncharacterized protein belongs to the Abi (abortive infection) family, which are commonly annotated as CAAX-proteases, and are significantly understudied in prokaryotes. In S. aureus the disruption of SAUSA300_1984 results in a drastic reduction of proteolytic and hemolytic activity, as well as diminished pigmentation. This phenotype appears to be mediated through …

Zonation Pattern And Spatial Arrangement Of A Geukensia Granosissima Population In A Mixed Mangrove Forest Of Tampa Bay, Derrick Shane Hudson

USF Tampa Graduate Theses and Dissertations

Here I provide the first report on Geukensia granosissima patterns of abundance along a tidal gradient within a mixed mangrove stand located in Tampa Bay, Florida, USA. Specifically, I examined 1) the relationship between G. granosissima size and density with mangrove root type (e.g. prop root, pneumatophore), and of density within the intertidal zones; and 2) the possible role of predation in shaping the lower zonation patterns displayed. Transect surveys located along the lower and upper population limit boundaries were conducted every two months over a ten-month period. Variables measured include size distribution, density of mussels, above ground mangrove prop …

Orthoplanar Spring Based Compliant Force/Torque Sensor For Robot Force Control, Jerry West

USF Tampa Graduate Theses and Dissertations

A compliant force/torque sensor for robot force control has been developed. This thesis presents methods of designing, testing, and implementing the sensor on a robotic system. The sensor uses an orthoplanar spring equipped with Hall-effect sensors to measure one component of force and two moment components. Its unique design allows for simple and cost effective manufacturing, high reliability, and compactness. The device may be used in applications where a robot must control contact forces with its environment, such as in surface cleaning tasks, manipulating doors, and removing threaded fasteners. The compliant design of the sensor improves force control performance and …

Heat Flux Modeling Of Asymmetrically Heated And Cooled Thermal Stimuli, Matthew Hardy

USF Tampa Graduate Theses and Dissertations

Thermal sensation is one of the most dynamic stimulus-response systems in the human body. It is relied upon for safety, comfort and general equilibrium of the human body. Thermal sensation is dependent upon many variables such as area of effected skin, rate of temperature change and location of stimulation. It has been shown that certain rates of change can intensify the sensation of heating or cooling. Conversely, sufficiently low rates of change can go undetected by the skin. As such, the thermal response system can be manipulated by the proper combination of applied hot and cold stimuli. Previous research has …

The Effect Of Behavioral Skills Training On Shot Performance In Field Hockey, Kelsey O'Neill

USF Tampa Graduate Theses and Dissertations

Behavior analysis procedures have been used to improve sports performance and enhance player safety across a wide variety of sports. The current study evaluated the effects of behavioral skills training on three common field hockey hits, a slap shot, drive, and sweep for young field hockey players. The procedures were evaluated in a multiple baseline across behaviors for three players. Results showed increases in each type of shot once intervention was implemented.

Media Velocity Considerations In Pleated Air Filtration, Frederik Carl Schousboe

USF Tampa Graduate Theses and Dissertations

Asset protection in the form of fluid filtration makes up an ever-increasing part of the civilized and industrialized world. Fluid filtration applications in the conditioned environment and life sciences are affording the world’s population a chance to better realize their potential, while industrial applications help ensure that high demand processes can be carried out safely, reliably, and effectively.

In the present work, a tool has been developed, using the computational fluid dynamics package FLUENT, to allow the designer to better predict the magnitude of geometric imperfections within a given pleat configuration.

Pleated rectangular filters, intended to improve the quality of …

An Exposure Assessment Of Paper Dust In A Coupon Manufacturing Facility, Danny C. Fink

USF Tampa Graduate Theses and Dissertations

Purpose. Exposures to paper dust, classified as Particulates Not Otherwise Regulated (PNOR), in an industrial setting can cause irritation to the eyes, skin, throat and upper respiratory tract. An exposure assessment was conducted to evaluate the paper dust exposures in the coupon manufacturing facility during a normal production working period. Methods. Total and respirable personal dust sampling was performed according to NIOSH 0500 and 0600 methods. Six total dust samples and seven respirable dust samples were taken within the sampling areas where airborne paper dust was produced to evaluate the Time Weighted Average (TWA) of the exposed employees. Results. Results …

Behind The Lens: The Pride And Politics Of Filmmaking In Ghana, Farah Leigh Vickery

USF Tampa Graduate Theses and Dissertations

This research looks at the production of media in Ghana, specifically, film produced in the “Glamour” style or Western-style tradition that originates in its capitol of Accra. The film industry in Ghana, known as Ghallywood, is a vibrant and prolific field in which content is produced and distributed throughout the country for local consumption. Research on production practice, rather than content, can show cross-cultural differentiation in visual media production and also offers a lens through which to explore Ghanaian culture. The following research questions frame this study: What are the production practices of Ghanaian video films? How do …

Simulation Of Hemiparetic Function Using A Knee Orthosis With Variable Impedance And A Proprioception Interference Apparatus, Christina-Anne Kathleen Lahiff

USF Tampa Graduate Theses and Dissertations

Individuals with stroke have neuromuscular weakness or paralysis on one side of the body caused by some muscles disengaging and overexciting other muscles. Hyperextension of the knee joint and complete lack of plantar flexion of the ankle joint are common symptoms of stroke. This thesis encompasses the simulation of hemiparetic function using both a knee orthosis with variable impedance, specifically in terms of stiffness and damping, and the Proprioception Interference Apparatus.

The section regarding the knee orthosis with variable impedance focuses on the creation and implementation of a small, lightweight, and adjustable orthotic device to be positioned around the knee …

Electrochemical Methods To Characterize Drilled Shaft Deficiencies, Sarah Jo Mobley

USF Tampa Graduate Theses and Dissertations

In recent years drilled shafts have become the preferred foundation method for marine bridges. Typically, the drilled shaft is selected over traditional driven piles due to soil strata encountered, construction economy, increased lateral stiffness requirements, and/or vibration control considerations. The most critical component in drilled shaft construction is borehole stabilization. Wall sloughing or groundwater inclusion can have devastating effects on the strength of the finished shaft however recent research has shown that the materials, more specifically the slurry, used to accomplish stabilization may be having a negative impact on the durability of the finished product. This thesis investigates the durability …

L’Évolution Du Petit Chaperon Rouge, Sophia Boules

USF Tampa Graduate Theses and Dissertations

Creating and writing fairy tales is a literary exercise that was introduced in the salons of the XVII century. Madame d'Aulnoy and Charles Perrault began to write the fairy tales that became fashionable at the court of King Louis XIV. Despite the simplicity of their narrative patterns, the tales carry messages that affect all readers. First addressed to adults, fairy tales dealt with anxieties, fears and desires of the human being.

Little Red Riding Hood is one of the most famous tales in the world. Universally loved, this cautionary tale has experienced much evolution through the centuries. There are some …

Something Looks Phishy Here: Applications Of Signal Detection Theory To Cyber-Security Behaviors In The Workplace, Jaclyn Martin

USF Tampa Graduate Theses and Dissertations

Cyber-security is an ever-increasing problem in the 21^st century. Though the majority of cyber-security breaches are a direct result of human error (Hu, Dinev, Hart, & Cooke, 2012), there is a dearth of research in psychology on the application of human decision-making for cyber-security compliance. Through an online inbox simulation, the present research examined the utility of a robust psychological model for decision-making, signal detection theory (SDT) for modeling decision-making in the context of receiving and responding to phishing and spear-phishing email scams. The influence of individual differences, specifically conscientiousness, on phishing email detection was also examined. The results …