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Effect Of Tricalcium Silicate Content On Expansion In Internal Sulfate Attack, Troy T. Whitfield

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to determine the cementitious parameters and placement temperature that impact internal sulfate attack in concrete. Concrete structures make up a large percentage of the infrastructure and multifamily housing. Durability is very important. Cements can be formulated to reduce the impact of external environmental exposure such as high salinity from marine environments or high sulfate levels from soils or surface waters. Concrete is also subject to internal attack such as alkali aggregate reaction, (AAR), and delayed ettringite formation, (DEF). This study focused on some of the cement chemistry issues that determine susceptibility of cement to …

Mentor And Mentee Perceptions Of The Importance And Effectiveness Of Mentor Support, Cenira Holcomb

USF Tampa Graduate Theses and Dissertations

This mixed-methods action research study explored the congruence between mentor and mentee perceptions of the importance and effectiveness of 12 district-specific focus areas of mentor support. While reviewing current data pertaining to teacher attrition, the researcher observed a limited availability of investigations relating to the perceived role of the mentor teacher based on the experiences and observations of both the novice and mentor teacher.The target population for this study was 70 novice and mentor special education teachers during the 2005--2006 school year employed at 13 middle schools in a school district located in Florida. Of the 70 beginning and mentor …

Interspecific Interactions Among Common Insects Of The Salt Myrtle, Baccharis Halimifolia L. (Asteraceae), Laura F. Altfeld

USF Tampa Graduate Theses and Dissertations

Baccharis halimifolia is host to many species of insect herbivore, including myrmecophilous aphids. Previous studies with B. halimifolia have revealed strong effects of competition by an early-feeding beetle, Trirhabda bacharidis, and nitrogen enrichment. The effects of ant mutualists, however, have not been evaluated for their potential influence on interspecific interactions among insects on the host plant. I have employed a series of experiments aimed at answering the following general questions. (1) How does the density of aphid-tending ants affect common insects on the host plant? (2) What are the relative effects of (a) competition from T. bacharidis, (b) nutrient enrichment, …

Petroleum Cleanup In The United States: A Historical Review And Comparison Of State Programs, Timothy A. Terwilliger

USF Tampa Graduate Theses and Dissertations

Cleanup of leaking underground storage tank (LUST) sites has been a priority for the United States of America (USA) for more than 20 years due to the large number of sites, the potential harmful health affects associated with gasoline components and the fact that single owners may not have the ability to pay for cleanup of these sites. In June 2006, the US Environmental Protection Agency (EPA) reported that of the 459,637 confirmed releases from USTs that had occurred previously, 342,688 had been remediated, which leaves 116,949 sites yet to be completed across the USA. Petroleum cleanup programs tend to …

Satellite Analysis Of Temporal And Spatial Chlorophyll Patterns On The West Florida Shelf (1997-2003), Lisa Anne Vanderbloemen

USF Tampa Graduate Theses and Dissertations

The objective of this dissertation is to gain a better understanding of the environmental and climatic effects on the temporal and spatial variability of phytoplankton biomass along the West Florida Shelf. Chapter 1 examines temporal and spatial patterns in chlorophyll concentrations using satellite data collected between 1997 and 2003. Chlorophyll data derived from the SeaWiFS sensor are validated with in-situ data and analyzed. Wind, current, sea surface temperature, river, and rain data are used to better understand the factors responsible for the patterns observed in the satellite data. My question is whether the standard OC4 algorithm is adequate for studying …

Implementing School-Wide Positive Behavior Support: Exploring The Influence Of Socio-Cultural, Academic, Behavioral, And Implementation Process Variables, Rachel Mara Cohen

USF Tampa Graduate Theses and Dissertations

This study evaluated the influence of academic, behavioral, and sociocultural variables on the implementation of Schoolwide Positive Behavior Support (SWPBS), a system intended to improve discipline in school buildings. The number of schools that are implementing SWPBS has been increasing dramatically over the years as school violence continues to rise and solutions are needed to improve school climate. This study examined the relationship between three categories of variables and the level of implementation of SWPBS in three multiple regression analyses. The categories were school demographic variables (i.e., ethnicity, socio-economic status, teacher: student ratio, percentage of teachers who are out-of-field), severity …

The Role Of Src Homology 2 Domain Containing 5' Inositol Phosphatase 1 (Ship) In Hematopoietic Cells, Caroline Desponts

USF Tampa Graduate Theses and Dissertations

The principal isoform of Src homology (SH) 2-domain containing 5' inositol phosphatase protein 1 (SHIP) is a 145kDa protein primarily expressed by cells of the hematopoietic compartment. The enzymatic activity of SHIP is responsible for hydrolyzing the 5' phosphate of phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P3), and thereby preventing the recruitment of pleckstrin homology domain containing effector proteins. Furthermore, SHIP contains protein-protein interaction domains, such as an SH2 domain, two NPXY and several proline-rich motifs. All of these different domains endow SHIP with the capacity to impact signaling pathways important for proliferation, survival, differentiation and activation. Therefore, we hypothesized that SHIP-deficiency could result in …

Drug Resistant Patterns Of Invasive Streptococcus Pneumoniae Infections In The State Of Florida In 2003, Michael T. Drennon

USF Tampa Graduate Theses and Dissertations

Streptococcus pneumoniae is a major bacterial pathogen which causes pneumoniae, meningitis, otitis media, and bacteremia. Currently there are two vaccines available, Pneumococcal Polysaccharide Vaccine (PPV) for adults and the Pneumococcal Conjugate Vaccine (PCV) for children. The PCV vaccine was developed in 2000 specifically for children and infants due to the ineffectiveness of the PPV vaccine in children. This is a cross sectional study of invasive S. pneumoniae in Florida during 2003. This study is designed to determine the population characteristics, clinically relevant antibiotic resistance patterns and specific risk factors for development of antibiotic resistance of invasive S. pneumoniae. Participants for …

Investigation Into The Hydrogen Gas Sensing Mechanism Of 3c-Sic Resistive Gas Sensors, Timothy J. Fawcett

USF Tampa Graduate Theses and Dissertations

The hydrogen (H2) gas sensing mechanism driving 3C-SiC resistive gas sensors is investigated in this work in which two hypotheses are proposed. One hypothesis involves the surface adsorption of H2 on the sensor surface with the adsorbed molecules influencing the flow of current in a resistive gas sensor, termed the surface adsorption detection mechanism. The second hypothesis includes the transfer of heat from the sensor to the gas, producing a change in the temperature of the device when the heat transfer characteristics of the gas change, termed the thermal detection mechanism. The heat transfer characteristics of the gas are dependent …

Alcohol Expectancy Cognitions: Psychophysiological Perspective, Inna Fishman

USF Tampa Graduate Theses and Dissertations

Considerable evidence indicates that the expectations individuals hold about the effects of alcohol determine, to a degree, the amount of alcohol they drink. However, the bulk of this evidence was acquired using verbally-based measures of expectancy. The present study sought to extend the validation network by utilizing an electrophysiological measure -- the P300 component of the Event Related Potentials (ERPs) --

which is thought to index fundamental neurophysiological processes sensitive to expectancy.Previous research has demonstrated that, when presented with various outcomes of alcohol consumption, heavier drinkers endorse statements that assert positive and arousing effects of alcohol, while lighter drinkers endorse …

Strategic Geographic Positioning Of Sea Level Gauges To Aid In Early Detection Of Tsunamis In The Intra-Americas Sea, Joshua I. Henson

USF Tampa Graduate Theses and Dissertations

A tsunami is a series of large amplitude, shallow water waves generated by an event capable of displacing a massive volume of water. The displaced water propagates at speeds in excess of 800 kph until it dissipates or impacts a shoreline where it slows to 30 --

50 kph [NOAA and USGS Fact Sheet, 2005]. Earthquakes are the predominant tsunamigenic event, however, landslides, avalanches, submarine slumps or slides, volcanic eruptions, volcano flank failure, and meteor impact into an ocean can also cause a tsunami [McCann, 2004; O'Loughlin and Lander, 2003; Pararas-Carayannis, 2004]. This study includes past Caribbean tsunamigenic events assumed …

Hollow-Electrode Pulsed Plasma Deposition Of Titanium And Carbon Thin Films, Robert H. Hyde

USF Tampa Graduate Theses and Dissertations

This thesis presents a study of a pulsed distributed arc plasma deposition method that has been developed to produce highly ionized pulsed plasma plumes of metallic species in the presence of a low-pressure inert or reactive gas glow discharge. A pulse-forming network (PFN) is used to form a transient electrical discharge in a hollow electrode which is triggered by two different methods; a pulsed CO2 laser or a pulsed high voltage glow discharge. With the PFN charged to a voltage of 70 - 100 VDC, current pulses with peak currents up to 3 kA and pulse widths as long 3.7 …

Measurement And Modeling Of Oxides Of Nitrogen From Vehicular Contributors, Kerstin Lesley Kenty

USF Tampa Graduate Theses and Dissertations

The focus of this research was the examination of the emission and transformation of nitrogen oxides emitted from vehicles. Measured data for this experiment were collected from May 1 thru May 31, 2002, and were compared to values modeled with CALINE4. CALINE4 is a photochemical and dispersive model used to predict concentrations of NOX (NO+NO2) from line sources. The measurement campaign was coincident with the Bay Regional Atmospheric Chemistry Experiment (BRACE). An ambient air quality monitoring site was constructed adjacent to Gandy Boulevard, in Tampa, FL. When comparisons of measured and modeled NO and NO2 values were made it was …

Vigilance In African Americans: Cardiovascular Reactivity And Phasic Heart Period Reactions To Cued Threat And Nonthreat Stimuli, Thomas Starr King

USF Tampa Graduate Theses and Dissertations

African Americans are at a greater risk of developing cardiovascular disease and associated risk factors than are Whites, and recent research has suggested that the effects of racial discrimination are a significant contributor to this disparity. Thus, a preattentive bias and vigilance for threat might serve as a mechanism through which experienced racial discrimination would negatively impact cardiovascular health. A study was conducted to investigate the physiological and attentional underpinnings of vigilance for discriminatory threat via examination of phasic heart period (HP) responses to cued threat and nonthreat stimuli. Thirty African American and forty-two European American undergraduate students from a …

Implications Of Sleep Disorders Symptoms On School Behavior, Academics, And Quality Of Life, Erin Elizabeth Ax

USF Tampa Graduate Theses and Dissertations

Pediatric sleep problems are among the most common yet significant pediatric health issues faced by families. Sleep problems can impact social-emotional and academic functioning of schoolchildren. Once identified, pediatric sleep problems and disorders are treatable with effective and rapid behavioral and medical interventions. The purpose of the current study was to determine the prevalence rates of symptoms of sleep disorders in a diverse school-based sample as well as the relationship between symptoms of sleep disorders and school behavior, academic achievement, and quality of life. The present study examined the relationship between the independent variables of No Sleep Disorders symptoms and …

Gold Mining In A Tropical Rainforest: Mercury Sorption To Soils In The Mining Region Of Arakaka-Mathew's Ridge, Guyana, Joniqua A'Ja Howard

USF Tampa Graduate Theses and Dissertations

Gold mining by artisinal (small-medium scale) miners causes an immense amount of damage to the environment (i.e. soil erosion, mobilization of heavy metals, etc.).1, 2 One of the most popular gold mining techniques employed by artisinal miners in Guyana is mercury amalgamation. During the amalgamation process approximately 300 metric tons/yr 11, 12 of mercury is used. Mercury once in the environment can be transported through the air, soil, and water column. It is estimated that 90-99% of total mercury (THg) is associated with the sediment. An understanding of the geochemical conditions that affect the fate of mercury in soils, which …

Tyrosinase-Like Activity Of Several Alzheimer's Disease Related And Model Peptides And Their Inhibition By Natural Antioxidants, Kashmir Singh Juneja

USF Tampa Graduate Theses and Dissertations

Neurodegenerative diseases are associated with loss of neurons ultimately leading to a decline in brain function. Alzheimer's disease (AD) is considered one of the most common neurodegenerative disorders that affects 16 million people worldwide. The cause of the disease remains unknown, although significant evidence proposes the amyloid Beta-peptide (A-Beta) as a potential culprit. The binding of Cu2+ by the soluble fragments of A-Beta have shown to form Type-3 copper centers and catalyze the oxidation of catechol-containing neurotransmitters. Furthermore, the use of flavonoids as antioxidants to slow or inhibit the neurotransmitter oxidation has suggested further health benefits with their consumption. A …

A Comparability Analysis Of The National Nurse Aide Assessment Program, Peggy K. Jones

USF Tampa Graduate Theses and Dissertations

When an exam is administered across dual platforms, such as paper-and-pencil and computer-based testing simultaneously, individual items may become more or less difficult in the computer version (CBT) as compared to the paper-and-pencil (P&P) version, possibly resulting in a shift in the overall difficulty of the test (Mazzeo & Harvey, 1988). Using 38,955 examinees' response data across five forms of the National Nurse Aide Assessment Program (NNAAP) administered in both the CBT and P&P mode, three methods of differential item functioning (DIF) detection were used to detect item DIF across platforms. The three methods were Mantel-Haenszel (MH), Logistic Regression (LR), …

Novel Sol-Gel Titania-Based Hybrid Organic-Inorganic Coatings For On-Line Capillary Microextraction Coupled To High-Performance Liquid Chromatography, Tae-Young Kim

USF Tampa Graduate Theses and Dissertations

Novel sol-gel titania-poly(dimethylsiloxane) (TiO2-PDMS) and titania-silica-N-(triethoxysilylpropyl)-O-polyethylene oxide urethane (TiO2-SiO2-TESP-PEO) coatings were developed for capillary microextraction (CME) to perform on-line preconcentration and HPLC analysis of trace impurities in aqueous samples. Due to chemical inertness of titania, effective covalent binding of a suitable organic ligand to its surface is difficult via conventional surface modification methods. In this research, sol-gel chemistry was employed to chemically bind hydroxy-terminated poly(dimethylsiloxane) (PDMS) and N-(triethoxysilylpropyl)-O-polyethylene oxide urethane (TESP-PEO) to sol-gel titania and sol-gel titania-silica network, respectively. A method is presented describing in situ preparation of the titania-based sol-gel PDMS and TESP-PEO coatings and their immobilization on the …

Group Fission-Fusion Dynamics And Communication In The Bottlenose Dolphin (Tursiops Truncatus), Ester Quintana-Rizzo

USF Tampa Graduate Theses and Dissertations

The bottlenose dolphin exhibits a fission-fusion social structure characterized by temporary associations lasting from minutes to hours. Although social structure has been described for some dolphin communities, the selective pressures affecting fission-fusion patterns and their consequences on dolphin communication are not well understood. The goals of the present study were three-fold: 1) to quantify the rate with which fission-fusion occurred and identify the selective pressures influencing an individual's decision to leave and join a temporary group; 2) to examine the communication signals produced during temporary separations; and 3) to estimate the distances over which dolphins could remain in acoustic contact …

Leadership Predictors Of Proactive Organizational Behavior: Facilitating Personal Initiative, Voice Behavior, And Exceptional Service Performance, Johannes Rank

USF Tampa Graduate Theses and Dissertations

Proactive organizational behavior is characterized by self-started and long-term oriented activities involving forward thinking and the intention to effect change in one's work environment. The primary objective of this research was to investigate relationships of supervisory behaviors with subordinates' personal initiative, voice behavior, and proactive service performance and to reveal moderators and mediators of these associations. Whereas personal initiative represents a wide range of proactive behaviors, voice behavior specifically reflects challenging and constructive forms of change-oriented communication. Drawing on the proactivity, service, and performance literatures, the proactive service performance construct was newly conceptualized as self-started and long-term oriented service behavior …

Women In Non-Traditional Careers, Teresa Ann Roche

USF Tampa Graduate Theses and Dissertations

In a traditional male dominated field such as construction, and automotive technology, artificial barriers and attitudes have often prevented qualified females from reaching their full potential. The late entrance of females into these fields has created very few role models for nontraditional younger females entering these professions. This study was designed to create a profile for nontraditional females working in a male dominated work force. A large percentage of females have experienced some barriers due to discrepancies in gender performance. Acceptance by peers, community and administrators, combined with the challenge of balancing family and career appears to be areas of …

Structure And Dynamics Of Heterogeneous Molecular Systems, Alfred B. Roney

USF Tampa Graduate Theses and Dissertations

Although current classical force fields describe homogeneous single-componentsystems fairly well, they do not represent the response of an individual molecule's electronic structure to its local environment with enough detail to reliably predict atomic motions in interfacial regions such as a solvation structure or liquid surface.Since most chemical processes of non-trivial interest involve two or more dissimilar molecules interacting at a short distance, molecular models must accurately simulate the interactions between different molecular species as well as bulk behavior in order to provide useful information. Results from two simulation studies are presented to illustrate both the utility of current point-charge electrostatics …

Design And Synthesis Of Core Structural Intermediates For Novel Hiv-1 Protease Inhibitors & Synthesis, Biological Activity And Molecular Modeling Of Novel 20s Proteasome Inhibitors, Kiran Kumar Venkata Raja Avancha

USF Tampa Graduate Theses and Dissertations

HIV-1 protease binds to its peptide/protein substrates in extended conformations. Therefore protease inhibitors that are constrained to form extended conformations are likely to produce very active protease inhibitors. This is because they are pre-organized to form favorable interactions with the enzyme environment immediately surrounding the active site. With this hypothesis in mind, we designed a family of structurally related molecules, which contain dipeptide analogs constrained to adopt the extended conformation. Core structural intermediates that are required for the total synthesis of the novel class of HIV-1 protease inhibitors are outlined in Chapter One. Chapter Two discusses the enantioselective synthesis of …

Are Respiratory Behaviors Affected In Individuals With Adductor Spasmodic Dysphonia?, Katie Biedess

USF Tampa Graduate Theses and Dissertations

Adductor spasmodic dysphonia (ADSD) is a focal dystonia that is characterized by voice breaks due to involuntary contractions of the adductor muscles of the vocal folds. These spasms can interfere with the coordination and balance of the respiratory and phonatory systems interfering with normal voice production. Disruptions in normal respiratory behaviors are well documented in inviduals with laryngeal disorders, including ADSD. Previous research regarding respiratory processes in ADSD has focused on airflow and pressure; however, there are many other parameters that have not been considered and may shed new light on the respiratory behaviors of individuals with ADSD. Therefore, the …

Crystal Engineering Of Organic Compounds Including Pharmaceuticals, Joanna A. Bis

USF Tampa Graduate Theses and Dissertations

Neutral or charge-assisted hydrogen bonds occurring between organic molecules represent strong and directional forces that mediate the molecular self-assembly into well defined supramolecular architectures. A proper understanding of hydrogen bonding interactions, their types, geometries, and occurrence in supramolecular motifs, is a prerequisite to crystal engineering, i.e. to the rational design of functional solid materials.Multiple-component organic crystals represent ideal systems to study the intermolecular interactions between the constituent molecules that can be pre-selected for their hydrogen bonding sites and geometrical capabilities. In particular, the systematic structural analysis of supramolecular systems that are comprised of simple molecules facilitates the development of strategies …

Rsvp: An Investigation Of The Effects Of Remote Shared Visual Presence On Team Process And Team Performance In Urban Search And Rescue Teams, Jennifer L. Burke

USF Tampa Graduate Theses and Dissertations

This field study presents mobile rescue robots as a way of augmenting communication in distributed teams through a remote shared visual presence (RSVP) consisting of the robot's view. It examines the effects of RSVP on team mental models, team processes, and team performance in collocated and distributed Urban Search & Rescue (US&R) technical search teams, and tests two models of team performance.

Participants (n=50) were US&R task force personnel drawn from high-fidelity training exercises held in California (2004) and New Jersey (2005). Data were collected from the 25 dyadic teams as they performed a 2 x 2 repeated measures search …

Stabilization Of Marginal Soils Using Recycled Materials, Delfin G. Carreon

USF Tampa Graduate Theses and Dissertations

Marginal soils, including loose sands, soft clays, and organics are not adequate materials for construction projects. These marginal soils do not possess valuable physical properties for construction applications. The current methods for remediation of these weak soils such as stone columns, vibro-compaction, etc. are typically expensive. Waste materials such as scrap tires, ash, and wastewater sludge, offer a cheaper method for stabilizing marginal soils. As an added benefit, utilizing waste materials in soil stabilization applications keeps these materials from being dumped into landfills, thereby saving already depleting landfill space. Included in this report is an extensive investigation into the current …

Monitoring Water Quality In Tampa Bay: Coupling In Situ And Remote Sensing, Zhiqiang Chen

USF Tampa Graduate Theses and Dissertations

Water quality in Tampa Bay was examined using concurrent in situ and satellite remote sensing observations. Chlorophyll and suspended sediment concentrations showed large short-term variability, primarily driven by tide and wind forcing. Superimposed on these high frequency variations were recurrent phytoplankton blooms stimulated by decreases in turbidity 1-2 days after wind-induced bottom sediment resuspension events; the blooms were particularly strong if neap tides occurred after the wind events. The in situ data show that observations once per month are inadequate to sample short-term variability and that therefore the current monthly water quality surveys may have uncertainties of -50 to 200% …

Traumatic Loss And Transformative Life Experiences: The Lived Experience Of Green Cross Traumatologists Deployed To The New York City World Trade Center Disaster, Carron C. Cherrie

USF Tampa Graduate Theses and Dissertations

This exploratory study examines the lived experience of Green Cross traumatologists deployed to the New York City World Trade Center disaster. The deployment took place five days after the terrorist attacks on September 11, 2001. The author was a member of a ten member advance team that provided crisis stabilization services to an international union in Lower Manhattan. Disaster Mental Health Services and community outreach were provided for a month. The purpose of the study was to describe in an anthropologically holistic perspective the lived experience of traumatologists, who as Americans were also affected by the terrorist disaster. Thirty-one traumatologists …