Digital Commons Network^™

Statistical Estimation Of Physiologically-Based Pharmacokinetic Models: Identifiability, Variation, And Uncertainty With An Illustration Of Chronic Exposure To Dioxin And Dioxin-Like-Compounds., Zachary John Thompson

USF Tampa Graduate Theses and Dissertations

Assessment of human exposure to environmental chemicals is inherently subject to uncertainty and variability. There are data gaps concerning the inventory, source, duration, and intensity of exposure

as well as knowledge gaps regarding pharmacokinetics in general. These gaps result in uncertainties in exposure assessment.

The uncertainties compound further with variabilities due to population variations regarding stage of life, life style, and susceptibility,

etc. Use of physiologically-based pharmacokinetic (PBPK) models promises to reduce the uncertainties and enhance extrapolation between species, between routes, from high to low dose, and from acute to chronic exposure. However, fitting PBPK models is challenging because of …

Comparative Developmental Transcriptomics Of Echinoderms, Roy Vaughn

USF Tampa Graduate Theses and Dissertations

The gastrula stage represents the point in development at which the three primary germ layers diverge. At this point the gene regulatory networks that specify the germ layers are established and the genes that define the differentiated states of the tissues have begun to be activated. These networks have been well characterized in sea urchins, but not in other echinoderms. Embryos of the brittle star Ophiocoma wendtii share a number of developmental features with sea urchin embryos, including the ingression of mesenchyme cells that give rise to an embryonic skeleton. Notable differences are that no micromeres are formed during cleavage …

Structure And Agency: An Analysis Of The Impact Of Structure On Group Agents, Elizabeth Kaye Victor

USF Tampa Graduate Theses and Dissertations

Different kinds of collectives help to coordinate between individuals and social groups to solve distribution problems, supply goods and services, and enable individuals to live fulfilling lives. Collectives, as part of the process of socialization, contribute to the normalization of behaviors, and consequently, structure our ability to be self-reflective autonomous agents. Contemporary philosophy of action models characterize collective action as the product of individuals who have the proper motivations to perform cooperative activities (bottom-up); or they begin with the social-level phenomena and explain this in terms of individual actions and the mental states that motivate them (top-down). One general goal …

Shelf-Scale Mapping Of Fish Distribution Using Active And Passive Acoustics, Carrie Christy Wall

USF Tampa Graduate Theses and Dissertations

Fish sound production has been associated with courtship and spawning behavior. Acoustic recordings of fish sounds can be used to identify distribution and behavior. Passive acoustic monitoring (PAM) can record large amounts of acoustic data in a specific area for days to years. These data can be collected in remote locations under potentially unsafe seas throughout a 24-hour period providing datasets unattainable using observer-based methods. However, the instruments must withstand the caustic ocean environment and be retrieved to obtain the recorded data. This can prove difficult due to the risk of PAMs being lost, stolen or damaged, especially in highly …

Something Is Askew In Florida's Water: Arguing For A Better Descriptive Statistic For Positively Skewed Water-Quality Data, Amie October West

USF Tampa Graduate Theses and Dissertations

ABSTRACT

It may be of no surprise that water quality data is right-skewed, but what appears to be overlooked by some is that the arithmetic mean and standard deviation most often fail as measures of central tendency in skewed data. When using the arithmetic mean and arithmetic standard deviation with nutrient data, one standard deviation about the arithmetic mean can capture nearly all of the data and extend into negative values. Representing nutrient data this way can be misleading to viewers who are using the statistics, and making assumptions, to understand the characteristics of those waters. Through an in-depth statistical …

Competing Narratives: Hero And Ptsd Stories Told By Male Veterans Returning Home, Adam Gregory Woolf

USF Tampa Graduate Theses and Dissertations

This qualitative study seeks to extend the existing body of scholarly literature on returned veteran civilian reintegration by exploring "hero" and "Post-Traumatic Stress Disorder" narratives. The character of the hero, as a social construct located within hegemonic notions of masculinity, is widely portrayed and believed to possess highly prized, extraordinary, almost superhuman personal qualities. However, this widely disseminated belief stands at odds with some of the stories returned veterans tell. This qualitative study explores and illuminates the enigmatic intersectionality of hero and PTSD narratives.

Extant hero and PTSD narratives contain paradoxical implicit meanings embedded within them. The hero is understood …

Catalytic Tri-Reforming Of Biomass-Derived Syngas To Produce Desired H2:Co Ratios For Fuel Applications, Devin Mason Walker

USF Tampa Graduate Theses and Dissertations

This study focuses on upgrading biomass derived syngas for the synthesis of liquid fuels using Fischer-Tropsch synthesis (FTS). The process includes novel gasification of biomass via a tri-reforming process which involves a synergetic combination of CO2 reforming, steam reforming, and partial oxidation of methane. Typical biomass-derived syngas H2:CO is 1:1 and contains tars that deactivate FT catalyst. This innovation allows for cost-effective one-step production of syngas in the required H2:CO of 2:1 with reduction of tars for use in the FTS. To maximize the performance of the tri-reforming catalyst, an attempt to control oxygen mobility, thermal stability, dispersion of metal, …

Evaluation Of Repeated Biomarkers: Non-Parametric Comparison Of Areas Under The Receiver Operating Curve Between Correlated Groups Using An Optimal Weighting Scheme, Ping Xu

USF Tampa Graduate Theses and Dissertations

Receiver Operating Characteristic (ROC) curves are often used to evaluate the prognostic performance of a continuous biomarker. In a previous research, a non-parametric ROC approach was introduced to compare two biomarkers with repeated measurements. An asymptotically normal statistic, which contains the subject-specific weights, was developed to estimate the areas under the ROC curve of biomarkers. Although two weighting schemes were suggested to be optimal when the within subject correlation is 1 or 0 by the previous study, the universal optimal weight was not determined. We modify this asymptotical statistic to compare AUCs between two correlated groups and propose a solution …

Asymmetric Intra- And Intermolecular Cyclopropanation By Co(Ii)- Based Metalloradical Catalysis, Xue Xu

USF Tampa Graduate Theses and Dissertations

Metal-catalyzed cyclopropanation of olefins with diazo reagents has attracted research interest because of its fundamental and practical importance. The resulting cyclopropyl units are recurrent motifs in biologically important molecules and can serve as versatile precursors in organic synthesis. Since they were first introduced in 2004, Co(II) complexes of D₂-symmetric chiral amidoporphyrins [Co(D₂-Por*)] have emerged as a new class of catalysts for asymmetric cyclopropanation. These metalloradical catalysts have been shown to be highly effective for asymmetric intermolecular cyclopropanation of a broad scope of substrates with different classes of carbene sources, particularly including electron-deficient olefins and acceptor/acceptor-substituted …

Smart Packaging: A Novel Technique For Localized Drug Delivery For Ovarian Cancer, Eva Christabel Williams

USF Tampa Graduate Theses and Dissertations

Localized drug delivery is emerging as an effective technique due to its ability to administer therapeutic concentrations and controlled release of drugs to cancer sites in the body. It also prevents the contact of harsh chemotherapy drugs to healthy regions in the body that otherwise would become exposed to current treatments.

This study reports on a model chemotherapy drug delivery system comprising non-ionic surfactant vesicles (niosomes) packaged within a temperature-sensitive chitosan network. This smart packaging, or package-within-a package system, provides two distinct advantages. First, the gel prevents circulation of the niosomes and maintains delivery in the vicinity of a tumor. …

The Mediating Effect Of Distress Caused By Constipation On Predictors Of Quality Of Life Of Hospice Patients With Cancer., Abdel Alkhalouf

USF Tampa Graduate Theses and Dissertations

Abstract

The Mediating Effect of Distress Caused by Constipation on Predictors of Quality of Life of Hospice Patients with Cancer.

Key positive outcomes for hospice patients include the prevention and alleviation of physical and psychological distress, maintenance of physical and mental functioning and all aspects of quality of life. This research used secondary analysis of previously gathered data to answer new research questions with alternative strategies to examine relationships not previously analyzed. The researchers collected data from 717 cancer patients who had been admitted to one of two private hospices. The aim of their experimental intervention was to define the …

Resisting Criminalization Through Moses House: An Engaged Ethnography, Lance Arney

USF Tampa Graduate Theses and Dissertations

Neoliberal restructuring of the state has had destructive effects on families and children living in urban poverty, compelling them to adapt to the loss of social welfare and demolition of the public sphere by submitting to new forms of surveillance and disciplining of their individual behavior. A carceral-welfare state apparatus now confines and controls the bodies of expendable laborers in urban spaces, containing their threat to the neoliberal socioeconomic order through criminalization and workfare assistance, resulting in a new symbiosis of prison and ghetto. The resulting structures of punishment, police surveillance, and criminalization primarily surround African Americans living in high …

Behavioral And Immunological Phenotypes Of Transgenic Mice Overexpressing Human Secreted Amyloid Precursor Protein Alpha: Implications For Autism, Antoinette R. Bailey

USF Tampa Graduate Theses and Dissertations

Autism is a heterogeneous neurodevelopmental disorder that is characterized by impaired social interaction and communication as well as restricted and repetitive behaviors and focused interests. In addition to the cardinal behavioral characteristics observed for diagnosis, autistic individuals exhibit a number of comorbid conditions as well as a variety of aberrant immunological features. Recent studies report that plasma from autistic children contained elevated levels of secreted amyloid precursor protein alpha (sAPP-á), the á-secretase cleavage product of the amyloid precursor protein (APP) which is ubiquitously expressed in the brain, spleen, thymus and other organs. Interestingly, the sAPP-á fragment functions as a neurotrophic …

Chemical Mechanical Planarization Of Electronic Materials, Fnu Atiquzzaman

USF Tampa Graduate Theses and Dissertations

In the modern semiconductor manufacturing processes, chemical mechanical planarization (CMP) has attained important processing step because of its ability to provide global planarization. CMP is the planarization technique which is used for the removal of excess material, as left over from the previous processing steps. In addition, CMP offers a uniform surface that is essential for subsequent processing steps, especially for the high resolution photolithography processes. In simpler notation, CMP is a process where a chemical reaction enhances in obtaining a planar surface through removal of the mechanical materials from a wafer.

In this study, CMP performance of three electronic …

Good Men Grow Corn: Embodied Ecological Heritage And Health In A Belizean Mopan Community, Kristina Linda Baines

USF Tampa Graduate Theses and Dissertations

Recent developments in land rights and land use in the Toledo district, Belize has generated anthropological and activist interest surrounding traditional ecological knowledge and practice, and the role of heritage in communities. This study explores the connection between ecological knowledge and practices, and the concurrent construction of heritage, and community health and wellness, broadly defined. Developing and using the concept of "embodied ecological heritage," this dissertation takes a phenomenological approach to understanding the convergence of ecological heritage and health in multiple realms of everyday life, arguing that lived experience of participating in "traditional" practices is fundamentally connected to wellness in …

Cloning Of The Gene, Purification As Recombinant Protein And Functional Characterization Of Leishmania Mexicana Cytochrome B5 Reductase, Ala Azhari

USF Tampa Graduate Theses and Dissertations

Leishmania are protozoan parasites that are transmitted by a sand fly vector. These parasites affect not only humans but also wild animals including domestic dogs and rodents, which form an additional challenge and public health problem to control the disease. Leishmaniasis is an important disease with worldwide distribution, including Saudi Arabia, the Middle East, and other tropical and subtropical areas around the world. Due to the expansion of irrigation and agricultural activities, more exposure to sand fly occurs, which leads to the expansion of leishmaniasis infections as newly emerging disease.

Emerging drug resistance in leishmaniasis is an additional problem, contributed …

Drug Discovery From Floridian Mangrove Endophytes, Jeremy Beau

USF Tampa Graduate Theses and Dissertations

A significant challenge of the 21st century is the growing health threat stemming from drug-resistant infectious diseases. There is an undeniable need to discover new, safe and effective drugs with novel mechanisms of action to combat this threat. A study of drugs currently on the market showed that natural products account for approximately 75% of new anti-infective drugs, either as new agents or analogs based upon their structure. Unfortunately, major pharmaceutical companies have cut back tremendously in natural products research in part due to the frustrating obstacle of frequent rediscovery of compounds. Fungi in particular are difficult to work with …

Synthesis And Anti-Mrsa Activity Of Hydrophilic C3-Acylated N-Thiolated Β-Lactams And N-Acyl Ciprofloxacin-N-Thiolated Β-Lactam Hybrids, Biplob Bhattacharya

USF Tampa Graduate Theses and Dissertations

The Turos laboratory has been working with N-thiolated β-lactams for years trying to understand the mode of action and structural features it needs to have biological activity. Over the years new data has shown promising inhibitory activity against various microbes.

In this dissertation, a review of the vast amount of work carried out on N-thiolated β-lactams in Turos laboratory has been done and their novelty, in terms of structure and mechanism has been discussed. A complete outline of our work in the discovery and ongoing development of these compounds, starting from our initial, unexpected finding of antimicrobial activity for one …

Stable Carbon Isotope Discrimination By Rubisco Enzymes Relevant To The Global Carbon Cycle, Amanda J. Boller

USF Tampa Graduate Theses and Dissertations

Five different forms of ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO; IA, IB, IC, ID, II), the carboxylase of the Calvin-Benson-Bassham cycle (CBB), are utilized by plants, algae and autotrophic bacteria for carbon fixation. Discrimination against ¹³C by RubisCO is a major factor dictating the stable carbon isotopic composition (δ¹³C = {[¹³C/¹²C sample/¹³C/¹²C standard] - 1} X 1000) of biomass. To date, isotope discrimination, expressed as ε values (={[¹²k/¹³k] - 1} X 1000; ¹²k and ¹³k …

Optimization Of An Advanced Water Treatment Plant: Bromate Control And Biofiltration Improvement, Dustin William Bales

USF Tampa Graduate Theses and Dissertations

The David L. Tippin Water Treatment Facility (DLTWTF) serving the city of Tampa, Florida is an advanced drinking water treatment facility consisting of coagulation/flocculation, ozonation, granular activated carbon biofiltration, and disinfection by chloramine. New regulations and the recent economic crisis pushed the facility to investigate methods to decrease costs and meet regulatory requirements easier.

The two major issues identified as priorities for investigation were the optimization of the biofiltration system and the use of a novel process to reduce the formation of bromate during ozonation.

Optimization of the biofiltration system is needed to remove more of the assorted particles that …

Bayesian Inference On Mixed-Effects Models With Skewed Distributions For Hiv Longitudinal Data, Ren Chen

USF Tampa Graduate Theses and Dissertations

Statistical models have greatly improved our understanding of the pathogenesis of HIV-1 infection

and guided for the treatment of AIDS patients and evaluation of antiretroviral (ARV) therapies.

Although various statistical modeling and analysis methods have been applied for estimating the

parameters of HIV dynamics via mixed-effects models, a common assumption of distribution is

normal for random errors and random-effects. This assumption may lack the robustness against

departures from normality so may lead misleading or biased inference. Moreover, some covariates

such as CD4 cell count may be often measured with substantial errors. Bivariate clustered

(correlated) data are also commonly encountered in …

Can You Believe She Did That?!:Breaking The Codes Of "Good" Mothering In 1970s Horror Films, Jessica Michelle Collard

USF Tampa Graduate Theses and Dissertations

The threats found in horror films change with time, each decade consisting of threats that were most frightening for the time period. Horror film scholars, such as Andrew Tudor, determined that in 1970s horror films the threat has migrated from external forces into the home and the family. Invading aliens and monsters were thrown replaced by psychosis and evil children. This notion of making the familiar unfamiliar and threatening is paralleled in concerns addressed during the second-wave of feminism; women were making the normative and familiar idea of mother unfamiliar as they migrated from the private and into the public …

Talking About Talk: The Problem Of Communication As An Object Of Study In Public Participation Research, Lauren Leigh Cutlip

USF Tampa Graduate Theses and Dissertations

When citizens participate in risk assessment and decision-making for environmental and other issues that affect members of the public, more robust decisions may be made. Public participation in policy decisions is not only more democratic, but it also enables members of the public to contribute valuable expertise to the decision-making process. However, the development of an effective forum for such participatory projects has been difficult. Participation mechanisms that foster dialogue and interactive exchange between participants have been regarded as the most beneficial, but the practical application of these mechanisms has been observed to be problematic. The goal of this study …

The Effects Of Food Insecurity On Mental Wellbeing In Monteverde Costa Rica, Robert Eugene Cowherd

USF Tampa Graduate Theses and Dissertations

The rapid expansion of ecotourism in the Monteverde zone of Costa Rica has increased the incidence in food insecurity in the area. Changes in food preferences and availability have led to a more homogenized diet that is increasingly delocalized and reliant on processed foods. Additionally, there has been a rapid economic shift away from agricultural and dairy farming to an economy more reliant on tourism. This NSF supported study builds upon data from a longitudinal investigation (#BNS 0753017) examining the nutritional effects of this rapid economic transition. Using a mixed methods approach, a culturally appropriate scale of stress was developed …

The Relationship Between The Social Construction Of Race And The Black/White Test Score Gap In, Toriano M. Dempsey

USF Tampa Graduate Theses and Dissertations

ABSTRACT

This research is an investigation into the relationship between the resegregation of American

public schools and the social creation of race. This research is based on the popular notion that

American public schools are failing to produce students capable of competing in today's global society.

The proof most often used to assert the failure of American public schools is the Black/White Test Score

Gap. For the purposes of this research the Black/White Test Score Gap is defined as the gap between

the scores on academic standardized tests between Black public school students and White public school

students regardless of …

Digital Holographic Measurement Of Nanometric Optical Excitation On Soft Matter By Optical Pressure And Photothermal Interactions, David C. Clark

USF Tampa Graduate Theses and Dissertations

In this dissertation we use digital holographic quantitative phase microscopy to observe and measure phase-only structures due to induced photothermal interactions and nanoscopic structures produced by photomechanical interactions. Our use of the angular spectrum method combined with off-axis digital holography allows for the successful hologram acquisition and processing necessary to view these phenomena with nanometric and, in many cases, subnanometric precision. We show through applications that this has significance in metrology of bulk fluid and interfacial properties.

Our accurate quantitative phase mapping of the optically induced thermal lens in media leads to improved measurement of the absorption coefficient over existing …

Crack Analysis In Silicon Solar Cells, Maria Ines Echeverria Molina

USF Tampa Graduate Theses and Dissertations

Solar cell business has been very critical and challenging since more efficient and low costs materials are required to decrease the costs and to increase the production yield for the amount of electrical energy converted from the Sun's energy. The silicon-based solar cell has proven to be the most efficient and cost-effective photovoltaic industrial device. However, the production cost of the solar cell increases due to the presence of cracks (internal as well as external) in the silicon wafer. The cracks of the wafer are monitored while fabricating the solar cell but the present monitoring techniques are not sufficient when …

Variability In Hydrology And Ecosystem Properties And Their Role In Regulating Soil Organic Matter Stability In Wetlands Of West-Central Florida, Sharon Jean Feit

USF Tampa Graduate Theses and Dissertations

Soil organic matter (SOM) provides many ecosystem services that are necessary for continued ecosystem function. The accumulation of SOM in an ecosystem is a function of its persistence time which can range from days to thousands of years. Ecosystem properties including dominant vegetation type, soil texture, and soil moisture in various habitats can regulate the persistence time of SOM.

Wetlands, because of their associated ecosystem properties, promote SOM accumulation, but little has been done to determine the ecosystem properties that regulate its persistence over time. In west-central Florida, urbanization and increased water demands have suppressed water tables in isolated wetland …

Aberrant Sialylation Alters Cardiac Electrical Signaling, Andrew Ednie

USF Tampa Graduate Theses and Dissertations

In the heart, electrical signaling is responsible for its rhythmicity and is necessary to initiate muscle contraction. The net electrical activity in a cardiac myocyte during a contraction cycle is observed as the action potential (AP), which describes a change in membrane potential as a function of time. In ventricular cardiac myocytes, voltage-gated sodium channels (Nav) and voltage-gated potassium channels (Kv) play antagonistic roles in shaping the AP with the former initiating membrane depolarization and the latter repolarizing it. Functional changes in the primary cardiac Nav isoform, Nav 1.5, or any one of the many Kv isoforms expressed in the …

Shape-Shifting Surfaces For Rapid Release And Direct Stamping Of Organized Micro-Tissues, Samuel James Dupont

USF Tampa Graduate Theses and Dissertations

The primary aim of the research in this study is to develop a robust and simple platform for the in vitro organization of cells on surfaces which facilitate rapid cell release and allows for the direct stamping of highly organized micro-tissues. Current approaches towards this goal have been very successful but are lengthy and subject cells to harsh conditions for extended periods of time raising questions regarding cell health and maintenance of physiological state. To address these concerns a platform was developed to allow for rapid cell release by utilizing a release mechanism different from previous work.

Micron-scale structures comprised …