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Sleep Duration, Postprandial Metabolic Function, And The Role Of Insulin Resistance In Nondiabetic Individuals, Karin A. Garcia Dec 2018

Sleep Duration, Postprandial Metabolic Function, And The Role Of Insulin Resistance In Nondiabetic Individuals, Karin A. Garcia

Open Access Dissertations

The influence of sleep duration on metabolic pathogenic pathways associated with Type 2 diabetes mellitus are not well understood but may be operational long before the development of clinical diabetes or even prediabetes is detected. This study was designed to examine in preclinical nondiabetic adults whether the association of insulin sensitivity and postprandial metabolic function is moderated by sleep duration. The sample was comprised of 143 individuals (65% men), aged 18–55 years, who had no diabetes or other diagnosed conditions. Metabolic function outcomes were assessed in response to an OGTT, and two 14-h serial mixed carbohydrate-meal tests administered, over 3 …


Can Digital News Shape Civic Participation? Discussion, Deliberation, And The Civic Potential Of A New Form Of News Delivery, Joy Kathleen Leopold Dec 2018

Can Digital News Shape Civic Participation? Discussion, Deliberation, And The Civic Potential Of A New Form Of News Delivery, Joy Kathleen Leopold

Open Access Dissertations

This study examines the features of an emerging and increasingly popular form of news delivery to assess its potential to influence civic participation. The innovative digital media environment has changed the way that news is produced and consumed, and digital news is consumed primarily through handheld communication devices such as smartphones and tablets. Research has demonstrated that news is an important element in driving civic participation due in part to the ways in which users consume and share news and in part to certain characteristics and features that promote learning, recall, influential discussions, and deliberation among news consumers. This research …


Identification And Quantification Of Wave Breaking Effects In Single-Polarization Along-Track Insar Imagery Of The Coastal Ocean, Conor J. Smith Dec 2018

Identification And Quantification Of Wave Breaking Effects In Single-Polarization Along-Track Insar Imagery Of The Coastal Ocean, Conor J. Smith

Open Access Dissertations

Spaceborne Along-Track Interferometric Synthetic Aperture Radar (along-track InSAR) has been used successfully to produce estimates of the surface current velocity field on a number of occasions. Along-track InSAR data are comprised of two complex images with a very short time lag, with each pixel containing an amplitude and phase. The phase difference allows a direct measurement of the line-of-sight velocity of the Bragg scattering ripples, which includes contributions of the horizontal surface current as well as the phase velocity of the Bragg ripples and orbital motions of longer waves. To calculate the surface current field, the complicated wave-related contributions to …


The Detection Of Hazardous Materials Using Genetically Engineered Bacteria, Daniel Wynn Dec 2018

The Detection Of Hazardous Materials Using Genetically Engineered Bacteria, Daniel Wynn

Open Access Dissertations

The development of technology that can be used to quickly and reliably assay a wide variety of matrices for the presence of specific small molecules has long been a high priority for scientists. These methods are valuable tools that see use in many fields, including biomedicine and environmental analysis. Although many contemporary technologies exist, their use is, for the most part, limited by their expense, required instrumentation, and long assay times. In an effort to address these limitations, many examples of biotechnology have been produced and this interest in biosensors continues. Herein, a number of projects to develop new bioanalytical …


Novel Methods For Improving Resolution In Liquid And Solid State Nuclear Magnetic Resonance Spectroscopy, Lauren Fae Odonnell Dec 2018

Novel Methods For Improving Resolution In Liquid And Solid State Nuclear Magnetic Resonance Spectroscopy, Lauren Fae Odonnell

Open Access Dissertations

NMR spectroscopy is a versatile analytical platform with a well developed theoretical foundation that makes it a popular vehicle for biological, chemical, material, and medical research. Successfully deciphering an NMR spectrum in order to extract important structural and chemical information typically requires the separation of overlapping signals that can be limited by the available spectral resolution, which is itself influenced by numerous factors such as molecular motions, spin-spin couplings, and field inhomogeneities. In this dissertation, methods for improving spectral resolution in both liquid and solids are explored. To begin, a brief introduction to NMR theory is provided which includes an …


Neuroimaging Of Cognitive Flexibility: Task Validity And Clinical Applications, Dina R. Dajani Dec 2018

Neuroimaging Of Cognitive Flexibility: Task Validity And Clinical Applications, Dina R. Dajani

Open Access Dissertations

A key challenge for cognitive neuroscience is the development and validation of tasks that capture real-world cognitive phenomena and render them suitable for investigation within an MRI environment. Cognitive flexibility is necessary for a range of adaptive behaviors and is associated with optimal life outcomes, but as a psychological construct it has been difficult to operationalize and validate. Crucially, psychometrically validated tasks must be developed prior to their application to clinical populations to investigate the neural substrates of cognitive inflexibility. Here, we address these limitations by adapting a well-validated laboratory measure of cognitive flexibility to the scanner environment (Study I) …


Controlling Photo Processes Within A Confined Space: Switches, Triggers, And Electron Transfer, Mohan Raj Anthony Raj Dec 2018

Controlling Photo Processes Within A Confined Space: Switches, Triggers, And Electron Transfer, Mohan Raj Anthony Raj

Open Access Dissertations

Many important biological processes, such as photosynthesis and vision are fueled by light. Selective photoisomerization of cis-retinal linked to rhodopsin protein causes vision. Biochemical structures like, pockets of enzymes, interiors of chaperones and inner-space of proteins are few examples of confined space in nature. Light seems to be an ideal external control element for many chemical and biological manipulations. In this work, we used water-soluble deep cavitand “octa acid” (OA) as a nanocarriers to carry out various photo processes like, photoswitches, phototriggers and electron transfer. We used NMR techniques to understand the encapsulation and photoreaction of guest molecules with OA …


Preschool Teachers' Science Knowledge: Validating The Preschool Teachers' Applied Science Knowledge Survey, Alexandra Danielle Alexander Dec 2018

Preschool Teachers' Science Knowledge: Validating The Preschool Teachers' Applied Science Knowledge Survey, Alexandra Danielle Alexander

Open Access Dissertations

Children are natural scientists, primed to investigate and evaluate their world. However, in the U.S., there are science achievement gaps already by kindergarten that persist through eighth grade. These achievement gaps coupled with stagnant and poor performance on science assessments have led to a current national focus on early science education. A likely contributor to these problems is the limited support that early science educators receive. Young children’s desire to understand their world is supported, nourished, and transformed into rigorous learning by adults. Supporting the adults in classrooms (i.e., early education practitioners) should, therefore, increase children’s learning. The present study …


Kaposi’S Sarcoma-Associated Herpesvirus-Encoded Viral Il-6 (Vil-6) Enhances Immunoglobulin Class-Switch Recombination, Santas Ana Rosario Dec 2018

Kaposi’S Sarcoma-Associated Herpesvirus-Encoded Viral Il-6 (Vil-6) Enhances Immunoglobulin Class-Switch Recombination, Santas Ana Rosario

Open Access Dissertations

Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic gamma-herpesvirus that causes several AIDS-defining malignancies, including Kaposi's sarcoma (KS) and other lymphoproliferative disorders. These malignancies continue to burden AIDS patients, particularly one-seventh of the world’s population in sub-Saharan Africa, where highly active antiretroviral therapy (HAART) is poorly accessible. To successfully establish lifelong persistence within a host, KSHV employs several strategies, including mimicry of host cytokines, to modulate the immune response and usurp cellular signaling pathways. One crucial cytokine is vIL-6, a viral homolog to human IL-6 (hIL-6) and mouse IL-6 (mIL-6). Although the immune system plays a pivotal role in the pathogenesis …


Developing An Online Computational Thinking Instrument For Elementary Students, Guanhua Chen Dec 2018

Developing An Online Computational Thinking Instrument For Elementary Students, Guanhua Chen

Open Access Dissertations

This study is part of a larger design study that iteratively improves a robotics programming curriculum as well as a computational thinking (CT) instrument. Its focus was majorly on CT assessment and particularly on an online CT instrument with logging functionality that can store a student's problem-solving process by recording interactions between a test-taker and the items with timestamps. The purposes of this research were to examine the psychometric properties of an online CT instrument, test if significant improvement in CT could be found by 200 5th graders who took a robotics programming course and the CT instrument as pretest …


Reconstructing Uncertain Response Surfaces With Application To Lagrangian Ocean Data, Rafael Carvalho Goncalves Dec 2018

Reconstructing Uncertain Response Surfaces With Application To Lagrangian Ocean Data, Rafael Carvalho Goncalves

Open Access Dissertations

Motivated by the problem of predicting the transport of material in the ocean, the present work went after two general problems. One is to use a probabilistic Lagrangian oil model to forecast the fate of an oil spill. The other is to use a dense array of Lagrangian observations to estimate the near surface submesoscale velocity field. Both problems were tackled with methodologies based on the reconstruction of response surfaces. In the first part, an uncertainty quantification methodology based on a non- intrusive polynomial chaos approach is developed for the forecasting of oceanic oil spills. This allows the model’s output …


Surface Chemistry And Spectroscopic Studies Of Enzymatic, Non-Enzymatic Molecules And Their Applications, Shiv K. Sharma Dec 2018

Surface Chemistry And Spectroscopic Studies Of Enzymatic, Non-Enzymatic Molecules And Their Applications, Shiv K. Sharma

Open Access Dissertations

The content of this thesis is an investigation into physicochemical, photophysical, and interfacial properties of β-galactosidase, a crucial enzyme, its conjugate with CDs, interaction of β-galactosidase with X-gal, and surface chemistry and spectroscopic study of toxins, Cholera toxin B (CTB) and Fumonisin B1 (FB1). The objective of the work was to understand the surface chemistry behavior of the important enzyme, conjugates and toxins in a model systems representing vaguely cell membrane environments, to prove the activity of the deposited enzyme, its conjugate, and toxins in a form of the monolayer. We also studied the effect of green LED light on …


Bioeconomic Consequences Of Fisheries Management: Florida's Commercial Reef Fisheries, Molly H. Stevens Dec 2018

Bioeconomic Consequences Of Fisheries Management: Florida's Commercial Reef Fisheries, Molly H. Stevens

Open Access Dissertations

The Florida reef ecosystem supports lucrative commercial and recreational industries that provide the state with billions of dollars annually. The goal of this study was to analyze the available demographic, fishery, and economic data for reef fishes, develop an age-structured bioeconomic production model, and assess the economic consequences of fisheries management. Key demographics data are required for the most basic assessment methodology, but just over half of these species had full parameter sets suitable for stock assessment, and less than a quarter had reliably estimated sets. Total mortality rates estimated from the average length of the commercial catch were combined …


Decoding The Sleep Homeostat Architecture, Andrey Lazopulo Dec 2018

Decoding The Sleep Homeostat Architecture, Andrey Lazopulo

Open Access Dissertations

Sleep is an ancient behavior that is observed in nearly all organisms. Animals typically spend a significant part of their life sleeping, and prolonged sleep deprivation leads to serious physiological changes, signifying the importance of sleep. However, little is known about the regulation of sleep. Sleep is thought to be controlled by two mechanisms: the circadian clock, a biological oscillator that controls daily activity, and the sleep homeostat that tracks organism’s sleep need and controls the duration of sleep. While the circuit of the circadian clock is well studied, almost nothing is known about the structure of the sleep homeostat. …


Making Covenants With Brute Beasts: Making Room For Non-Human Animals In A Contractualist Framework, Jennifer Lynn Burgis Dec 2018

Making Covenants With Brute Beasts: Making Room For Non-Human Animals In A Contractualist Framework, Jennifer Lynn Burgis

Open Access Dissertations

In this dissertation I explore the question of whether T.M. Scanlon's contractualist ethical theory can be revised such that the resulting theory makes room for moral obligations to non-human animals. A number of attempts have been made to justify our intuitions regarding the treatment of animals, but none of these has succeeded. I argue that Scanlon's reliance on the rationality criterion is flawed and that a focus on moral capacities creates both a more inclusive and a more satisfying moral framework. By building on Julia Driver's objective consequentialist account of virtue, I am able to support the claim that, at …


Cement-Based Composites For Rehabilitation Of Concrete Structures, Houman Akbari Hadad Dec 2018

Cement-Based Composites For Rehabilitation Of Concrete Structures, Houman Akbari Hadad

Open Access Dissertations

Inorganic based composites are a new class of materials used in strengthening and rehabilitation of masonry and concrete structures. In the literature, these composites have been identified using different terminology, among which, Fabric Reinforced Cementitious Matrix (FRCM) and Steel Reinforced Grout (SRG) are adopted by the North American guidelines and acceptance criteria. FRCM fabric/s may consists of carbon, aramid, glass, basalt or polyparaphenylene benzobisoxazole (PBO) fiber rovings that are embedded in an inorganic matrix. SRG shares the same technology with FRCM, except that the fabrics consist of twisted galvanized steel wires which form steel cords. Developed as alternatives to fiber-reinforced …


Hispanic Ethnicity And Poison-Related Outcomes, Florida 2010-2015, Wendy Blair Stephan Dec 2018

Hispanic Ethnicity And Poison-Related Outcomes, Florida 2010-2015, Wendy Blair Stephan

Open Access Dissertations

Poisoning is the leading cause of injury death in the United States, with most fatal poisonings resulting from drug overdoses in adults. Much remains unknown about epidemiologic factors at the county level that might affect population risk for poison-related outcomes. Hispanic individuals consistently have lower death and hospitalizations rates from poisoning, so it was hypothesized that having a larger proportion of Hispanic residents, might, in effect, “protect” a county from high rates of poisoning. This ecological, longitudinal study examined Hispanic concentration at the county-level in Florida and the incidence of poison death, nonfatal hospitalizations from poisoning, and calls to poison …


Effects Of Temperature, Ultraviolet Radiation And Crude Oil Exposure On Early-Life Staged Mahi-Mahi (Coryphaena Hippurus), Christina Pasparakis Dec 2018

Effects Of Temperature, Ultraviolet Radiation And Crude Oil Exposure On Early-Life Staged Mahi-Mahi (Coryphaena Hippurus), Christina Pasparakis

Open Access Dissertations

The timing and location of the 2010 Deepwater Horizon (DWH) disaster within the Gulf of Mexico resulted in crude oil exposure of many commercially and ecologically important fish species, such as mahi-mahi (Coryphaena hippurus), during their sensitive early life stages (ELS). Mahi produce positively buoyant and rapidly developing embryos. Therefore, ELS mahi may be directly exposed to the cardiotoxic tricyclic PAHs dominating the oil slicks in surface waters for a significant portion of their developmental period. Further, these embryos are transparent and are likely also exposed to simultaneous stressors occurring in surface waters, known to act synergistically in the presence …


The Social Context Of Women's Sustained Participation In Activism, Susan Paterson Dec 2018

The Social Context Of Women's Sustained Participation In Activism, Susan Paterson

Open Access Dissertations

Recently, the resurgence of interest in feminist activism has been discussed by media and news outlets. It is still relatively unknown what contextual factors affect sustained participation, as well as how women from different backgrounds sustain activism in the face of compounding oppressions. This grounded theory explores the contexts of sustained participation through two research questions: (1) what are the contextual factors that influence women's sustained participation in activism?, and (2) how is the dynamic between identity and context reflected in sustained participation in activism? Nine women activists in Miami-Dade County were interviewed about their experiences in feminist movements, specifically …


Polycomb Complexes Associate With Enhancers To Regulate Oncogenic Pathways In Cancer, Ho Lam (Candy) Chan Dec 2018

Polycomb Complexes Associate With Enhancers To Regulate Oncogenic Pathways In Cancer, Ho Lam (Candy) Chan

Open Access Dissertations

The Polycomb repressive complexes play diverse and essential roles in cell fate decisions, embryonic development, stem cell pluripotency, and gene regulation. There are two main Polycomb complexes in mammalian cells, Polycomb Repressive Complex 1 and 2 (PRC1 and PRC2). PRC1 can be further subdivided into canonical and non-canonical complexes depending on its composition (cPRC1 and ncPRC1). Historically, Polycomb complexes have been mostly associated with maintaining gene repression carried out by its histone-modifying and chromatin-remodeling capabilities. Specifically, PRC1 can catalyze mono-ubiquitination of histone H2A on lysine 119 while PRC2 trimethylates histone H3 on lysine 27. Both these histone marks are associated …


Quantifying The Effect Of Tropospheric Delay On Interferometric Synthetic Aperture Radar And Its Application To Crustal Deformation, Emre Havazli Dec 2018

Quantifying The Effect Of Tropospheric Delay On Interferometric Synthetic Aperture Radar And Its Application To Crustal Deformation, Emre Havazli

Open Access Dissertations

Interferometric Synthetic Aperture Radar (InSAR) is a powerful tool to detect and monitor ground deformation. It has been widely used to study deformation processes caused by tectonic (e.g. earthquakes, volcanoes) and non-tectonic (e.g. sinkholes, city subsidence) processes using phase differences between two acquisitions over the same area. However, there are several limitations for InSAR method. Tropospheric phase delay is currently the major source of error in InSAR. This study explores the detection limits of InSAR and quantifies the effect of tropospheric delay on In-SAR time series products, such as velocity fields, using simulation of tropospheric delay approach (Chapter 3) and, …


Subaltern Communication For Social Change: The Struggles Of Manual Scavengers In India, Sheeva Yamunaprasad Dubey Dec 2018

Subaltern Communication For Social Change: The Struggles Of Manual Scavengers In India, Sheeva Yamunaprasad Dubey

Open Access Dissertations

This study aims to contribute to the theoretical discourse of Communication for Social Change (CSC) by expanding its theoretical scope beyond its current framework. The current theoretical framework of CSC is dualistic, with one-way modernization-diffusion paradigm on one end and the two-way dialogue-participation paradigm on the other. I argue that the understanding of both these paradigms in CSC discourse is based on planned and externally-driven approaches to social change. Such planned theoretical perspectives are insufficient for the purpose of explaining the autonomous struggles of marginalized, disadvantaged, and subaltern communities. I propose a third category for consideration in the theoretical framework …


Modeling The Effect Of Seasonality On The Transmission Of Antibiotic Resistance Bacteria In Hospitals With Environmental Contamination, Qimin Huang Dec 2018

Modeling The Effect Of Seasonality On The Transmission Of Antibiotic Resistance Bacteria In Hospitals With Environmental Contamination, Qimin Huang

Open Access Dissertations

Nosocomial infections caused by antibiotic resistant bacteria are a major threat to global public health today. In order to understand the diverse factors contributing to hospital acquired antibiotic resistant infections, we develop some mathematical models and address the theoretical, numerical and stochastic aspects of such models. In Chapter 2, both deterministic and stochastic mathematical models are developed to explore the roles that antibiotic exposure and environmental contamination play in the transmission dynamics of nosocomial infections in hospitals. Uncolonized patients without or with antibiotic exposure, colonized patients without or with antibiotic exposure, uncontaminated and contaminated health-care workers, and free-living Methicillin-resistant {\it …


Salient Factors Among Hispanic Parents For Vaccinating Children Against Hpv, Madeline Fernandez Nov 2018

Salient Factors Among Hispanic Parents For Vaccinating Children Against Hpv, Madeline Fernandez

Open Access Dissertations

The human papillomavirus (HPV) is the most common sexually transmitted infection (STI) among sexually active men and women in the U.S. HPV can lead to several types of cancers (e.g., cervical, penile, and anal cancers) that affect the Hispanic community disproportionately. In the U.S., Hispanic women have the highest rate of HPV incidence and the second highest death rate due to HPV-related cervical cancer, and Hispanic men are most affected by HPV-related penile cancers. In 2006, the HPV vaccine (HPVV) was released and recommended for girls and boys between the ages of nine and 26. Unfortunately, more than a decade …


Elucidating The Mechanism Of Cancer Drug Addiction In Alk+ Alcl, Soumya Sundara Rajan Nov 2018

Elucidating The Mechanism Of Cancer Drug Addiction In Alk+ Alcl, Soumya Sundara Rajan

Open Access Dissertations

The NPM1-ALK fusion kinase drives ALK-positive anaplastic large cell lymphoma (ALK+ ALCL). Mechanisms of NPM1-ALK-driven lymphomagenesis are well defined, but mediators of cancer drug addiction in cells overexpressing it are unknown. Cancer drug addiction arises paradoxically when tumors become dependent on exposure to inhibitors to which they formerly were sensitive. We and others demonstrated previously that addiction to tyrosine kinase inhibitors (TKIs) occurs in resistant ALK+ ALCL over-expressing NPM1-ALK. It is unknown, however, if addiction mechanisms defined recently for solid tumors addicted to MEK/ERK inhibitors apply also to these kinase-driven lymphomas. We consistently found that MEK/ERK activation and other oncogenic …


A Comparative Analysis Of Techniques Of Euphonium And Vocal Performance Using Acoustical Properties, Brian Logan Nov 2018

A Comparative Analysis Of Techniques Of Euphonium And Vocal Performance Using Acoustical Properties, Brian Logan

Open Access Dissertations

After researching that many brass pedagogy texts make allusions to vocal performance as the ideal standard, this essay observed the ability of the euphonium performer to create different articulation sounds. Comparisons between voice and brass articulations were made. The effectiveness was determined by comparing pertinent acoustical components of brass methods to that of a single vocalist. To begin, this study catalogued preeminent suggested techniques for performing brass articulation found in method, pedagogy, magazine, and personal memoire texts. These techniques were collected into a list and given to a euphonium player subject from the University of Miami. In an anechoic chamber, …


Salt Detection And The Influence Of Anorectic Drugs Of Abuse In The Taste System, Jennifer Katherine Roebber Nov 2018

Salt Detection And The Influence Of Anorectic Drugs Of Abuse In The Taste System, Jennifer Katherine Roebber

Open Access Dissertations

Taste cells detect five different gustatory modalities: sweet, sour, bitter, umami, and salty. The mechanisms, cells and transductional events that underlie sweet, sour, bitter and umami taste are well characterized. However, salt taste is poorly understood. The ability to detect NaCl is partially, but not fully, blocked by the diuretic amiloride. In both taste buds and in kidneys, a primary target of amiloride is the epithelial sodium channel (ENaC). As such, the field has interpreted amiloride sensitive salt taste to rely on Na+ influx through ENaCs while another unknown receptor detects amiloride-insensitive salt taste. The cell type(s), mechanisms and cell-signaling …


Holocene-Pleistocene Climate Variability Through Stalagmites, Sevag Mehterian Nov 2018

Holocene-Pleistocene Climate Variability Through Stalagmites, Sevag Mehterian

Open Access Dissertations

Understanding the changing climate of the past is the key to understanding the changing climate of the present. Historically, various geologic mediums have been used to unearth the mysteries of the ancient past. These include cores of sediment from deep within the oceans, ice cores from glaciers, skeletons of coral reefs, and stalagmites from inside caves. This dissertation aims to shed light on the climate of the past 300,000 years as recorded within the geochemistry of stalagmites from caves in the Bahamas and Iran. With oxygen and carbon stable isotope geochemistry, radiometric dating through Uranium and Thorium, and trace elemental …


Mitochondrial Dna Fate And Deletion Formation Following Double-Strand Breaks, Nadee Nissanka Nov 2018

Mitochondrial Dna Fate And Deletion Formation Following Double-Strand Breaks, Nadee Nissanka

Open Access Dissertations

Mitochondrial DNA (mtDNA) deletions have been identified in patients with bona-fide mitochondrial disorders as well as implicated in normal aging. The mechanism of how these deletions form is still debated – some possibilities include formation as a result of errors in replication, double-strand breaks (DSBs), or during mtDNA repair. Due to the multi-copy nature of mtDNA, usually following DSB, there is a rapid degradation of linear mtDNA fragments instead of repair. The goals of this study were to first understand which nucleases play a role in mtDNA degradation following DSBs and second to generate and characterize murine cellular models harboring …


Radiative Transfer Diversity And Its Influence On The Response Of The Hydrological Cycle In Climate Models, Ryan Joseph Kramer Nov 2018

Radiative Transfer Diversity And Its Influence On The Response Of The Hydrological Cycle In Climate Models, Ryan Joseph Kramer

Open Access Dissertations

Due to considerable societal implications, accurately simulating the response of the hydrological cycle to climate change is an important focus of climate research. Currently, climate model simulations predict the hydrological cycle will strengthen globally with global warming, but the magnitude of this change remains highly uncertain. Here we identify sources of this uncertainty by diagnosing individual components of the radiative changes that constrain the hydrological cycle response. We show that the differing influences of CO2 increases on long-term anthropogenic climate change versus short-term internal climate variability explains differences in precipitation sensitivity on these time scales. We investigate the response of …