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

American Studies Commons™

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

27,372 Full-Text Articles 16,645 Authors 30,803,571 Downloads 273 Institutions

All Articles in American Studies

Faceted Search

27,372 full-text articles. Page 664 of 727.

Parametric And Bayesian Modeling Of Reliability And Survival Analysis, Carlos A. Molinares 2011 University of South Florida

Parametric And Bayesian Modeling Of Reliability And Survival Analysis, Carlos A. Molinares

USF Tampa Graduate Theses and Dissertations

The objective of this study is to compare Bayesian and parametric approaches to determine the best for estimating reliability in complex systems. Determining reliability is particularly important in business and medical contexts. As expected, the Bayesian method showed the best results in assessing the reliability of systems.

In the first study, the Bayesian reliability function under the Higgins-Tsokos loss function using Jeffreys as its prior performs similarly as when the Bayesian reliability function is based on the squared-error loss. In addition, the Higgins-Tsokos loss function was found to be as robust as the squared-error loss function and slightly more efficient. …


In The Midst Of Organizational Change: A Survey Of Employee Perceptions Toward Separate Accreditation For Regional Campuses At The University Of South Florida, Rhonda S. Moraca 2011 University of South Florida

In The Midst Of Organizational Change: A Survey Of Employee Perceptions Toward Separate Accreditation For Regional Campuses At The University Of South Florida, Rhonda S. Moraca

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to identify how employees in the University of South Florida System (USF System) perceived changes in their organizations and the system as a result of having separate accreditation for each campus in the USF System. This survey research provided a "snapshot" of employee perceptions at a particular point in time. The study was unique because it provided a picture of the perceptions of employees while each campus was at a different point in the organizational change process. The theoretical concept from Bolman and Deal's (2003) four frame theory was used to develop the dependent …


Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris 2011 University of South Florida

Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris

USF Tampa Graduate Theses and Dissertations

Ammonium (NH4+) is a biological nutrient that is transformed in a wastewater treatment plant (WWTP) in a process called activated sludge. This is accomplished in an aerobic environment using microorganisms and inorganic carbon that convert the ammonium to nitrate (NO3-). This process is termed nitrification. Removal of ammonium is necessary due to its oxygen demand and toxicity to the environment.

Nitrification is considered a slow process due to the slow growth rate of the nitrifying bacteria. Ammonia oxidizing bacteria (AOB) first covert the ammonium (NH4+) to nitrite (NO2-) …


The Threat To Democracy In Brazil's Public Sphere, Daniel Nettuno 2011 University of South Florida

The Threat To Democracy In Brazil's Public Sphere, Daniel Nettuno

USF Tampa Graduate Theses and Dissertations

This thesis looks at the nature of violence with its endemic, and increasingly epidemic presence in Brazil. I analyze the structure of the justice system, police force, and the many governmental security programs in order to better explain why Brazil is so violent and its government has been unable to control this violence. Living under violent conditions, Brazil has become a society where the efficient functioning of the public sphere has been undermined. This public space, shared by citizens, is what many academics believe to be a critical component of a robust and functioning democracy. In Brazil, it is shown, …


To See And Be Seen: Exploring Layers Of Instructional Leadership And Supervision In The Enactment Of A District-Wide Teacher Evaluation Reform, Jenifer E. Neale 2011 University of South Florida

To See And Be Seen: Exploring Layers Of Instructional Leadership And Supervision In The Enactment Of A District-Wide Teacher Evaluation Reform, Jenifer E. Neale

USF Tampa Graduate Theses and Dissertations

This dissertation analyzes instructional leadership and evaluation protocols from a large, diverse district in the Southeastern United States in order to investigate layers of accountability and tensions created when principals are asked to fill the dual roles of both instructional leader and supervisor in a newly implemented teacher evaluation system reform. For this dissertation I investigate the role of the principal as a colleague and mentor and compare this with the role of the principal as supervisor and evaluator in hierarchical systems. I include the role of the peer evaluator, a new position, in my analysis. Critical discourse analysis is …


Evaluating The Get Into Fitness Today (Gift) Program: Weight Loss And The Roles Of Education And Empowerment, Emily Koby Novicki 2011 University of South Florida

Evaluating The Get Into Fitness Today (Gift) Program: Weight Loss And The Roles Of Education And Empowerment, Emily Koby Novicki

USF Tampa Graduate Theses and Dissertations

This study investigated the effects of Get Into Fitness Today (GIFT), a health program for adults that promotes balanced nutrition, physical activity, and weight loss through weekly meetings that provide education and social support. In addition to investigating the effects of GIFT, this evaluation sought to better understand explanatory models used by participants and program staff, and the roles of education and empowerment in weight loss and health education. This mixed methods, case study evaluation consisted of quantitative analysis of existing program records for 664 participants, 40 hours of participant observation of class sessions with ten GIFT groups, and follow-up …


Visual Search For Smoking Stimuli: Detection And Distraction, Jason A. Oliver 2011 University of South Florida

Visual Search For Smoking Stimuli: Detection And Distraction, Jason A. Oliver

USF Tampa Graduate Theses and Dissertations

Extensive research has shown that the attentional systems of addicted individuals are biased towards drug-related stimuli, but despite several decades of effort these results have frequently been inconsistent. Though commonly believed to result from addiction and dependence, cognitive research would suggest that frequent exposure to drug-related stimuli could affect the attentional processing of drug-related cues even if no actual drug use occurs. The present investigation examined attentional bias for smoking cues using a novel visual search paradigm amongst smokers currently in nicotine withdrawal and fully satiated smokers, as well as a non-smoker control group. Variables related to smoking behavior, as …


Nearer, My Farm, To Thee: A Spatial Analysis Of African American Settlement Patterns In Hillsborough County, Florida, Matthew Andrew O'Brien 2011 University of South Florida

Nearer, My Farm, To Thee: A Spatial Analysis Of African American Settlement Patterns In Hillsborough County, Florida, Matthew Andrew O'Brien

USF Tampa Graduate Theses and Dissertations

Geographic Information Systems (GIS) have demonstrated their utility in predictively modeling the location of archaeological sites, and providing a framework for cataloging sites eligible for heritage management status. The intent of this GIS-based study is to begin to create a geohistorically organized database of information culled from historic documents and archaeological excavation. In this case study of postbellum land tenure in Hillsborough County, Florida, a GIS-based approach is used to demonstrate the impacts of federal and state land ownership policy decisions during the Reconstruction Era and beyond. GIS data are also used to reveal information about how people use their …


Effectiveness Of In-Line Chlorination Of Gravity Flow Water Supply In Two Rural Communities In Panama, Kevin Orner 2011 University of South Florida

Effectiveness Of In-Line Chlorination Of Gravity Flow Water Supply In Two Rural Communities In Panama, Kevin Orner

USF Tampa Graduate Theses and Dissertations

It is well established that water quality is directly linked to health. In-line chlorination is one technology that can be used in the developing world to potentially inactivate pathogens and improve water quality. The purpose of this study was to determine the effectiveness of the Panamanian Ministry of Health's in-line PVC chlorinator under three different operating conditions in a rural water supply system. Free and total chlorine were measured entering the storage tank, leaving the storage tank, and at three households along the transmission line of the water system in the two rural indigenous communities of Calabazal and Quebrada Mina …


Catalytic Hydrodehalogenation And Hydrogenation Of Halogenated Aromatic Organic Contaminants For Application To Soil Remediation, Claire J. Osborn 2011 University of South Florida

Catalytic Hydrodehalogenation And Hydrogenation Of Halogenated Aromatic Organic Contaminants For Application To Soil Remediation, Claire J. Osborn

USF Tampa Graduate Theses and Dissertations

The objective of this research was to aid in the development of a new method for removing and destroying soil contaminants. In particular, 1,2,4,5-tetrachlorobenzene (TeCB) was selected for this research. Hydrodehalogenation (HDH) was paired with hydrogenation for remedially destroying TeCB without generating a secondary waste stream in a single batch reactor. Palladium- and rhodium-catalyzed HDH and hydrogenation were applied in a batch reactor at room temperature and moderate hydrogen pressure. Cyclohexane was formed as an end product with benzene as an intermediate reactant.

An analytical method was developed to measure TeCB, benzene, and cyclohexane in a solution of water and …


Crystal Engineering Of Molecular And Ionic Cocrystals, Tien Teng Ong 2011 University of South Florida

Crystal Engineering Of Molecular And Ionic Cocrystals, Tien Teng Ong

USF Tampa Graduate Theses and Dissertations

Solubility enhancement of poorly-soluble active pharmaceutical ingredients (APIs) remains a scientific challenge and poses a practical issue in the pharmaceutical industry. The emergence of pharmaceutical cocrystals has contributed another dimension to the diversity of crystal forms available at the disposal of the pharmaceutical scientist. That pharmaceutical cocrystals are amenable to the design principles of crystal engineering means that the number of crystal forms offered by pharmaceutical cocrystals is potentially greater than the combined numbers of polymorphs, salts, solvates and hydrates for an API. The current spotlight and early-onset dissolution profile ("spring-and-parachute" effect) exhibited by certain pharmaceutical cocrystals draw attention to …


Evaluating The Effectiveness Of Irrigation Restrictions Within Key Communities In Tampa, Florida, Lin Allen Ozan 2011 University of South Florida

Evaluating The Effectiveness Of Irrigation Restrictions Within Key Communities In Tampa, Florida, Lin Allen Ozan

USF Tampa Graduate Theses and Dissertations

The City of Tampa, Florida has instituted water restrictions over the past decade that have been primarily aimed at mitigating non-essential usage of water resources by limiting domestic lawn irrigation. The mandatory restrictions are enforced by the issuance of citations to violators, which is intended to promote compliance and deter from subsequent violations. This thesis provides a thorough investigation of historical water restriction with relation to compliance in order to determine which factors might be related to high rates of water usage within key Tampa communities. The objectives are to: (1) develop a GIS data set that can be used …


Use Of Innovative Computer Technology And Optical Texture Properties In The Analysis Of Pavement Digital Images, Saumya Priyadari Amarasiri 2011 University of South Florida

Use Of Innovative Computer Technology And Optical Texture Properties In The Analysis Of Pavement Digital Images, Saumya Priyadari Amarasiri

USF Tampa Graduate Theses and Dissertations

Digital image based automated pavement crack detection and classification technology has seen vast improvements in the recent years. In spite of these developments, although pavement crack lengths and widths can be evaluated using state-of-the-art software with a reasonable accuracy, no reported evidence is found in extending this technology to evaluate crack depths. Hence a preliminary study was carried out to model the digital image formation of cracked concrete pavements based on the Bidirectional Reflection Distribution Function. It was revealed that a definitive theoretical relationship exists among the crack widths and depths and the maximum pixel intensity contrasts in the images …


Surface Functionalization And Analysis Thereof For An Ovarian Cancer Diagnostic Biosensor, Asad Ali Ahmad 2011 University of South Florida

Surface Functionalization And Analysis Thereof For An Ovarian Cancer Diagnostic Biosensor, Asad Ali Ahmad

USF Tampa Graduate Theses and Dissertations

Ovarian cancer is the fifth leading cause of cancer death among women in United States and has an alarming 1.4% (1 in 71) lifetime risk. The lack of overt symptoms and the absence of a reliable screening test to detect ovarian cancer result in over 70% of women being diagnosed after the disease has spread beyond the ovary resulting in a poor prognosis. A key characteristic of ovarian cancer is the ability of tumor cells to evade apoptosis, or programmed cell death contributing to the limitless replicative potential, which is a hallmark of all carcinogenesis. There is conclusive evidence that …


Contextualizing Hiv/Aids Prevention And Treatment Programs In Zanzibar, Tanzania, Naheed Ahmed 2011 University of South Florida

Contextualizing Hiv/Aids Prevention And Treatment Programs In Zanzibar, Tanzania, Naheed Ahmed

USF Tampa Graduate Theses and Dissertations

International aid organizations and wealthy nations have contributed billions to combat the spread and treatment of HIV/AIDS in sub-Saharan Africa; however, these programs have been critiqued for not addressing the socioeconomic and cultural context of the epidemic, instead relying upon generalized approaches. The prevalence rate in Zanzibar, Tanzania is low in the general population, but high among vulnerable segments of Zanzibari society, resulting in interventions focusing on particular groups (e.g. sex workers, drug users, and men who have sex with men). Through interviews with government agencies, non-profit organizations, medical professionals, vulnerable populations, and HIV/AIDS patients, this paper examines how local …


Thermal Response Of Lithium Tantalate For Temperature Measurement, Ardit Agastra 2011 University of South Florida

Thermal Response Of Lithium Tantalate For Temperature Measurement, Ardit Agastra

USF Tampa Graduate Theses and Dissertations

This thesis describes the study of the thermal response of the pyroelectric material named lithium tantalate or LT (LiTaO3) in aid of this material’s possible use for temperature measurement. The temperature range studied was between 5-99 oC. The sensor was excited using a silicon rubber heater. The lithium tantalate sensor and the rubber heater were enclosed such that the temperature would reach steady state faster. The enclosure was a small insulated box in order to reduce any extraneous effects on the sensor. The output signal of the lithium tantalate sensor was then amplified by using four different amplifying circuits and …


Sol-Gel Resorcinarene Sorbent For Capillary Microextraction Coupled To Gas Chromatography, Abdullah Awadh Alhendal 2011 University of South Florida

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 …


Perceptions By Heartland Educational Consortium (H.E.C.) Elementary Title I School Principals And Assistant Principals: Data Use In Their Role As Achievement-Related Decision Makers, Sherri Albritton 2011 University of South Florida

Perceptions By Heartland Educational Consortium (H.E.C.) Elementary Title I School Principals And Assistant Principals: Data Use In Their Role As Achievement-Related Decision Makers, Sherri Albritton

USF Tampa Graduate Theses and Dissertations

In the age of accountability and assessment, there is a need to ensure that data provided regarding student achievement can be effectively and appropriately utilized by school site administrators in a systematic way to improve student achievement.

This study identified Heartland Educational Consortium Title I principals’ and assistant principals’ perceptions of their use of data as decision-makers in raising student achievement, with primary emphasis on Florida’s Differentiated Accountability Model.

Quantitative results revealed statistically significant differences in data use by administrators. Use of data by administrators for professional development was statistically significantly different from school improvement, leadership, or data skills. Data …


The Relationships Between Frontal Alpha Asymmetry, Mood, And Emotional Memory, Ross Avila 2011 University of South Florida

The Relationships Between Frontal Alpha Asymmetry, Mood, And Emotional Memory, Ross Avila

USF Tampa Graduate Theses and Dissertations

Frontal alpha asymmetry is often used as a metric to compare activation between homologous frontal brain sites. A positive asymmetry refers to greater activation in the left hemisphere than in the right hemisphere, while the opposite is true of negative asymmetries. Two expansive but largely separate bodies of research have examined the relationships between (1) frontal asymmetry scores and mood, and (2) mood and emotional memory performance. Specifically, one body of research has found that positive moods are associated with positive asymmetries while negative moods are associated with negative asymmetries. A second body of literature has examined the effects of …


Perceptions On Collaborative Learning: A Case Study Of Female Community College Instructors, Marilyn Christine Armstrong 2011 University of South Florida

Perceptions On Collaborative Learning: A Case Study Of Female Community College Instructors, Marilyn Christine Armstrong

USF Tampa Graduate Theses and Dissertations

In the 1980s, academic assessments called for "the ability of individuals and groups to talk, listen judge, and act on issues of common interest" (Morse, 1989, p. 30). More recently, corporate research findings, Are They Ready to Work? Employers' Perspectives on the Basic Knowledge and Applied Skills of New Entrants to the 21st Century U.S. Workforce (The Conference Board, Inc., Partnership for 21st Century Skills, The Corporate Voices for Working Families, & Society for Human Resource Management, 2006), report the workplace is seeking college graduates with skill in collaboration (e.g. build diverse relationships, negotiate, manage conflict). While the interest in …


Digital Commons powered by bepress