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Development Of An In Vivo Fundus Imaging And Retinal Optical Coherence Tomography System For The Mouse, Omer Pars Kocaoglu

Open Access Dissertations

The purpose of this project is to develop a retinal imaging system suitable for routine examination or screening of mouse models that acquires fundus and Optical Coherence Tomography (OCT) images. The imaging system is composed of a digital camera with an objective for biomicroscopic examination of the fundus, an OCT interferometer, an OCT beam delivery system designed for the mouse eye, and a mouse positioning stage. The image acquisition is controlled with software that displays the fundus and OCT images in real-time, and allows the user to control the position of the OCT beam spot on the fundus image display. …

Validation Of The Social Communication Questionnaire (Scq) In A Hispanic Sample: Understanding The Impact Of Expressed Emotion, Vanessa Gonzalez

Open Access Dissertations

The SCQ is a popular screener for ASDs derived from the gold-standard diagnostic interview. This study examined the validity of the SCQ in a Hispanic sample. Additionally, the mother's expressed emotion toward her child with ASD was examined. Participants included 217 Hispanic and non-Hispanic white mothers of children with and without ASDs ages 4-10. The actual diagnostic status of all children was determined using a historical review of records. ROC curve analysis yielded much lower sensitivity and specificity than the original validation study, with very little difference found between the 15 and 22 cutoffs. A cutoff score of 12 performed …

Receptor Selective Coactivators:Characterization Of A Novel Protein-Protein Interaction Module In Steroid Hormone Receptor Signaling, Sarath C. Dhananjayan

Open Access Dissertations

WW-domain binding protein-2 (WBP-2) was cloned as an E6-associated protein (E6-AP) interacting protein and its role in steroid hormone receptor (SHR) function was investigated. We show that WBP-2 differs from other SHR coactivators, as it specifically enhanced the transactivation functions of progesterone receptor (PR) and estrogen receptor (ER alpha), whereas it had no significant effect on the androgen receptor, glucocorticoid receptor or the activation functions of p53 or VP-16. We also demonstrated that, like other well characterized coactivators, WBP-2 contains an intrinsic activation domain. Depletion of endogenous WBP-2 with small interfering RNAs indicated that normal physiological protein level of WBP-2 …

Automatic Classification Of Long Term Involuntary Spontaneous Emg, Jeffrey S. Winslow

Open Access Dissertations

Involuntary electromyographic (EMG) activity has been recorded in the thenar (thumb) muscles of spinal cord injured (SCI) subjects for only short time periods (minutes), but it is unknown if this motor unit activity is ongoing. Longer duration EMG recordings can investigate the physiological significance of this neuromuscular activity. Analysis of these data is complex and time consuming. Since no software is currently capable of classifying 24 hours of data at a single motor unit level, the goal of this research was to devise an algorithm to automatically classify motor unit potentials over 24-hours. Twenty-four-hour, 2-channel thenar muscle EMG recordings were …

Belly Laughs: Body Humor In Contemporary American Literature And Film, David Gillota

Open Access Dissertations

Belly Laughs: Body Humor in Contemporary American Literature and Film Scholars are more than happy to laugh at but seem somewhat reluctant to discuss body humor, which is perhaps the most neglected form of comedy in recent criticism. In this dissertation, I examine the ways in which contemporary American writers and filmmakers use body humor in their works, not only in moments of so-called "comic relief" but also as a valid way of exploring many of the same issues that postmodern artists typically interrogate in their more somber moments. The writers discussed in this project-Philip Roth, Thomas Pynchon, Charles Johnson, …

More Than The Sum Of Its Parts: Physical And Mechanistic Coupling In The Phage Lambda Red Recombinase, Gokhan Tolun

Open Access Dissertations

In many dsDNA viruses, a single-strand-annealing homologous recombination (SSA) reaction is catalyzed by a pair of proteins. In phage lambda, this system is called Red, and is composed of lambda exonuclease (Lambda-Exo, a 5' to 3' dsDNA exonuclease), and Red-Beta (a ssDNA binding protein and annealase). I examined the physical and mechanistic coupling of Lambda-Exo and Red-Beta and confirmed that these proteins form a complex with a 1:1 subunit stoichiometry. The size of this complex was shown to be close to one MDa, possibly composed of 12 Lambda-Exo and 12 Red-Beta monomers. Red-Beta decreased the extent of digestion of dsDNA …

Physical And Biological Characteristics Of Billfish Spawning Habitat In The Straits Of Florida, David Earl Richardson

Open Access Dissertations

The objective of this dissertation was to examine sailfish (Istiophorus platypterus) and blue marlin (Makaira nigricans) spawning in the Straits of Florida, with a specific focus on 1) the physical and biological characteristics of the spawning environment, and 2) the role of the region within the broader spawning patterns of these two species. In order to accomplish these objectives, two years of monthly ichthyoplankton collections and physical measurements across the Straits of Florida were combined with a finer-scale Lagrangian study. Additionally, a molecular species-identification methodology was developed that was both high-throughput and suitable for use with a broad taxonomic range …

Distribution, Reproduction, And Transport Of Zooplankton In The Western Arctic, Leopoldo Llinas

Open Access Dissertations

This dissertation focuses on the distribution, reproduction, and transport of zooplankton in the Chukchi and Beaufort seas and adjacent Canada Basin. Specifically, it analyzes 1) the species-specific distribution of copepod nauplii as it is forced by the surface layer mesoscale circulation and physical properties, 2) the reproduction of the dominant copepod Calanus glacialis in the western Arctic, and 3) the effects of eddy transport on the zooplankton community in the Chukchi and Beaufort seas and Canada Basin. To achieve this I adapted a molecular identification method to work with small crustaceans. The method was successfully used to generate a sequence …

The Outer Limits: Telomere Maintenance By Trf2 And G-Quadruplex Dna Structures, Ilene M. Pedroso

Open Access Dissertations

Human telomeric DNA consists of tandem repeats of the sequence 5'-d(TTAGGG)-3' assembled into a nucleoprotein complex that functions to protect the ends of chromosomes. Such guanine-rich DNA is capable of forming a variety of G-quadruplexes, which in turn, can have varying functional consequences on telomere maintenance. G-quadruplex stabilizing ligands have been shown to induce chromosome end-to-end fusions, senescence and apoptosis, effects similar to the expression of a dominant-negative TTAGGG Repeat Factor 2 (TRF2). With this in mind, we analyzed the effect of sequence and length of human telomeric DNA, as well as cation conditions on G-quadruplex formation by native polyacrylamide …

Nitrogen Cycling On Coral Reefs: A Stable Isotopic Investigation Of Nutrient Dynamics Within The Florida Keys Coral Reef Tract, Kathryn Amanda Lamb-Wozniak

Open Access Dissertations

This dissertation serves as a comprehensive, natural-abundance analysis of the present-day spatial and temporal dynamics and trophic linkages of nitrogen from within the Florida Keys National Marine Sanctuary (FKNMS). This work was accomplished by documenting the delta 15 N of particulate organic matter (POM), several genera of aquatic vegetation and herbivorous fish, as well as dissolved water column nitrogen. Seasonal and spatial variations in delta 15 N were assessed, trophic level variations among reef constituents were quantified, and relative contributions of both natural and anthropogenic nitrogen into the reef tract were determined. The measured mean delta 15 N of POM …

Examination Of Spot, Rpos And Rpon Gene Expression In Response To Fatty Acid Starvation In Borrelia Burgdorferi, The Lyme Disease Spirochete, Wendy Meredith Coy

Open Access Dissertations

The purpose of the present investigation is to examine the regulation and expression of the B. burgdorferi spoT/rpoS pathway under normal growth conditions and during serum starvation in wild-type strains and in spoT, rpoS and rpoN mutant strains. Additionally the expression of B. burgdorferi's rpoN gene has been examined within a surrogate Escherichia coli system by using a GFP reporter construct in order to determine if SpoT, RpoS or RpoN affect rpoN expression. In this study, we examined the affects of mutating the spoT, rpoS and rpoN genes. These genes are known to be both affected by starvation and to …

Forest Management In The Presence Of Harvest Restrictions Around Vernal Pools: A Metaheuristic Approach, Gabriela Dobrot

Open Access Dissertations

The primary objective of this research is to model the economic opportunity costs of alternative harvest restrictions aimed at conserving and sustaining ecological functions of vernal pools. The simulations performed incorporate a series of economic and ecological factors in order to determine: alternative configurations of canopy cover around the ponds which could produce similar adoption costs, in both a non-spatial and a spatially defined forest structure, optimal harvest schedules when a mix of tree species is being introduced on the studied landscape, as well as the sensitivity of this schedule to different stumpage prices. Methodologically, the results in this study …

Effect Of Varying Inclusion Levels Of Linseed Oil On Growth, Fatty Acid Profile, Membrane Fluidity And Epa/Dha Production In Atlantic Salmon (Salmo Salar), Mary Anne Eaton

Open Access Dissertations

Fish oil accounts for approximately 26.8% of the operating costs of salmon aquaculture. To compensate for the increasing demand in fish oil, alternative plant and animal oils have been used to replace the fish oil. The goal of this study was to formulate a cost-effective fish feed which supports adequate growth of salmon and is less susceptible to oxidative damage while maintaining the characteristic beneficial fatty acid profile. Experiments were undertaken to assess the growth, fatty acid profile, erythrocyte membrane fluidity, and ability of liver hepatocytes to convert linolenic acid to EPA and DHA in Atlantic salmon with inclusion of …

Sediment Transport In A Dynamic, Tidally-Influenced Coastal Embayment Exemplified By Pleasant Bay And Chatham Harbor, Cape Cod, Massachusetts, Mark Borrelli

Open Access Dissertations

Sediment transport in a coastal embayment was documented on multiple spatial and temporal scales. An inlet formed in Chatham Harbor in 1987 and as a result the primary flood-tidal delta began to migrate. The relationship between the evolution of the tidal inlet and the flood-tidal delta was documented using field studies and spatial analyses of georeferenced aerial photographs. A feedback mechanism was documented such that the migrating flood-tidal delta increases in surface area, which causes the ebb-tidal flow to become more channelized, which in turn allows more intertidal area to be created by flood-tidal currents and further channelizing ebb-tidal flow. …

An Examination Of The Relationships Between The Peptide Hormone Ghrelin And Appetite, Plasma Biomarkers Of Satiety And Metabolic Response In Humans, Daniel Lee Kresge

Open Access Dissertations

The peripherally circulating peptide hormone ghrelin is purported to stimulate hunger and feeding in humans, and is affected by the energy storage state as reflected in body mass index and body composition, and by macronutrient content of the diet. There have been few studies in humans that have measured both ghrelin, in its various isoforms, and appetite. To address this, Manuscript #1 of this dissertation examined fasting and postprandial ghrelin and ratings of appetite, in addition to anthropometric and fitness measures in 50 college-age student. There were no significant correlations between fasting or postprandial ghrelin and appetite or anthropometric measures …

The Formulation And Process Development Of A Novel Multiparticulate Extended Release Pharmaceutical Delivery Platform For A Highly Water Soluble Compound, Cyrus D. Agarabi

Open Access Dissertations

This research compared a traditional drug development approach with an enhanced "Quality by Design" (QbD) approach to foster greater process and formulation understanding. Propranolol HCl extended release capsules and Metoprolol Succinate extended release tablets served as targets for development. The formulation and process parameters utilized well-established techniques, such as wet granulation, extrusion, spheronization, and fluid bed processing with commercially available aqueous or organic polymeric systems.

Propranolol HCl extended release capsules were a benchmark for current generic pharmaceutical process development to identify basic parameters for a suitable product. Metoprolol Succinate extended release tablets utilized the ICH Q8 annex guidelines approach to …

Evaluation Of A Novel Autonomous Detector For Microbial Water Quality Monitoring, Heather L. Saffert

Open Access Dissertations

Rapid testing methods are needed for monitoring waters for fecal contamination to identify associated health hazards. Today, standard methods quantify the amount of indicator bacteria, E. coli and enterococci, using culture-based techniques that require incubation periods from 18 to 48 hours. For recreational waters, this time lag delays the closure of waters when a potential health hazard exists and prolongs closures after contamination has dissipated. A remotely deployable, autonomous sampler capable of rapid automated data analysis and reporting of fecal contamination would provide a more effective warning system for both managers and the public. An in situ instrument may also …

Speaking Out: Class, Race, And Gender In The Writings Of Ruth Mcenery Stuart, Edith Summers Kelley, And Harriette Simpson Arnow, Claire E. Reynolds

Open Access Dissertations

This study analyzes representations in American fiction of social issues during periods of national turmoil. Ruth McEnery Stuart, Edith Summers Kelley, and Harriette Simpson Arnow draw characters marginalized by class, gender, race, and ethnicity who negotiate survival amid crisis and adverse socioeconomic conditions. Giving voice to people who could not speak for themselves, the texts perform the work of cultural resistance to a discourse that privileges capitalism, patriarchy, and white supremacy while oppressing the poor, women, and non-whites. Following an introductory chapter, I present the authors and their works chronologically, beginning each chapter with a brief overview of the historical …

Tandem Conjugate Addition -- Cyclization Reactions Of L-Methyl Prolinate With α,β-Unsaturated Ketones Catalyzed By L-Proline, Sergio Sandoval

Open Access Dissertations

L-methyl prolinate and various α,β-unsaturated ketones were reacted by a tandem sequence of conjugate addition and subsequent autocatalytic intramolecular cyclization to yield 1,3-dicarbonyl-pyrrolizidine ring systems in modest yield. This methodology represents a tandem and green preparative reaction sequence where L-proline is self-generated as an organocatalyst subsequent to the first step and prior to the second step of the process. This sequence of reactions is a one-pot, tandem, and green preparative reaction for the synthesis of various pyrrolizidine derivatives which can be performed in a general and simple way under solventless and room temperature conditions. This methodology is modest yielding and …

Study On The Nonenzymatic Glycation Of Nucleosides/Nucleotides And Proteins With Sugars: An In Vitro Investigation Of Advanced Glycation Endproducts (Ages) Formation, Yuyuan Li

Open Access Dissertations

Advanced glycation endproducts (AGEs) are a complex and heterogeneous group 1 of compounds formed by the nonenzymatic reactions of the carbonyl groups of reducing sugars with the free amino groups of biomolecules. Nonenzymatic reactions can occur in vitro and in vivo and affect the structure, function and conformation of many biomolecules, and AGEs has been suggested to associate with the pathogenesis of various disease such as diabetes and Alzheimer disease. The increased number of reports on the nonenzymatic glycation of proteins and nucleic acids has generated great interest in the methods for characterization of AGEs. The lack of universally applicable …

Interpersonal And Psychosexual Factors Predicting Hiv-Related Risky Sex Behaviors In Heterosexually Active Women And Men, Asako C. Matsuura

Open Access Dissertations

This study focused on psychosexual and interpersonal constructs and their relationship with partner risk and unprotected intercourse, based on the multifaceted model of HIV risk (MMOHR). The model was examined for 625 men and women (ages 18-24); the model was then compared across gender. The MMOHR-based model was strongly supported. Having a higher sense of self-efficacy in using condoms, and a higher sense of assertiveness in practicing prevention both predicted decreased unprotected vaginal intercourse. Contrastingly, those better able to refuse unwanted sexual advances were more likely to report unprotected vaginal intercourse. Condom use assertiveness significantly predicted condom self-efficacy and condom …

The Relationship Between Self-Efficacy And Decisional Balance For Stress Management And Exercise Behavior In An Adolescent Population: A Cross-Lagged Panel Analysis, Catherine Stephan

Open Access Dissertations

In the world of increasing levels of stress and declining rates of exercise in today's youth, the development of effective intervention strategies for stress management and exercise behavior is crucial for the promotion of healthy physical and mental health lifestyles in adolescent populations. Utilizing Grant's Model of Adolescent Psychopathology and key theoretical constructs from the Transtheoretical Model of Change (TTM), this study examined the relationship between self-efficacy and decisional balance measures within and across two target behaviors (stress management, exercise). The current study included 996 high school students from the state of Rhode Island who participated in a larger four-year, …

Classroom-Based Empathy Training: An Evaluation Of Program Effects In An Elementary School, Kimberly Sherman

Open Access Dissertations

Universal classroom-based social skills and violence prevention training is currently a topic of widespread interest. Although there is a growing body of empirical support for some existing social skills programs, less is known about contributions of specific program components to intervention outcomes. Empathy training is one common component of social skills curricula that has been subject to relatively little research. The current study is a single-school quasi-experimental investigation of Second Step empathy training effects on 57 first- and fourth-graders. Dependent variables included self-reported empathy, teacher-reported social skills, teacher-reported problem behaviors, and fourth-graders' self-reported social skills. The study also explored teachers' …

Coping With Everyday Classism: Exeriences Of Low-Income People In A Southeastern Rural Community, Susan Faye Ritz

Open Access Dissertations

The present research provided an in-depth look at experiencing and coping with everyday classism in a sample of low-income. people in a mid-size southeastern rural United States community. The study employed a qualitative methodology consisting of semi-structured interviews and analyzing the collected data using Grounded Theory Method. Of 50 participants selected for an interview, 40 described experiences with classism, each discussing two incidents, for a total of 80 incidents shared. Seven of the remaining 10 participants felt that they had not experienced class ism, but at the same time, they provided insight into one proactive coping strategy that they appeared …

Design And Evaluation Of Nucleoside Derivatives For Targeted Drug Delivery And Therapeutic Applications, Hitesh Kumar Agarwal

Open Access Dissertations

2',3'-Dideoxynucleoside analogs are commonly used as anti-HIV, anti-HBV, and anti-cancer drugs. Despite of their potent activities, there are some major limitations in using 2',3'-dideoxynucleosides as therapeutic agents. The nucleosides have usually poor cellular uptake because of their hydrophilic nature. Some of the nucleoside analogs, such as anti-HIV agents, become ineffective after multiple administrations because of the development of the drug resistance, and therefore they must be administered in combination therapy. It is hard to deliver the nucleoside analogs to a particular tissue for site specific targeting. Furthermore, nucleoside analogs undergo three intracellular phosphorylation steps to become active. The first phosphorylation …

Experimental And Computational Study Of The Detection And Stability Of Polymorphs Using Pxrd, Dsc And Solubility, David F. Wells

Open Access Dissertations

Reliable detection of polymorphs and mixed phase crystal systems is an important area of investigation in the development of pharmaceutical (small molecule) ingredients. This work deals specifically with small molecular entities as distinguishable from large or macromolecules, which also are used as active pharmaceutical ingredients. The first manuscript describes a digital band-pass filter for removal of white noise in Powder X-ray Diffraction. The filter reduces the noise by 21% for a real PXRD diffractogram and 40% for a synthetic PXRD diffractogram while maintaining the integrity of diffraction intensities and diffraction angle positions. The solid phase form of an active pharmaceutical …

Advances In Global Optimization, Rajeswar R. Gattupalli

Open Access Dissertations

Optimization is an active area of research and an important computational tool in many fields of science and engineering. While many effective global optimization algorithms have been developed over the past decades, there is still a need for improved robustness, reliability and efficiency. Examples where improvements in robustness, reliability and efficiency are needed include finding the global minimum of molecular modeling problems and finding all physically relevant solutions for mathematical models of chemical engineering applications. This dissertation describes two novel advanced global optimization tools--a multi-scale terrain/funneling methodology and logarithmic barrier-terrain method--that provide improved robustness, reliability and computational efficiency for solving …

Silane-Based Copolymers As Chromatographic Stationary Phases, Deidre Lynn Blackwell

Open Access Dissertations

In this work, a group of thermally stable polar-embedded polymer based stationary phases are presented. The silane-based copolymer is synthesized by radical polymerization to incorporate polar groups, through phenylmaleimides, and alkoxysilane groups. By way of the alkoxysilane groups, the copolymer can be attached on to silica particles or converted to polymer-silica composite particles using tetraethoxysilane (TEOS) as a sol-gel precursor. Through characterizations in this work, they proved to be stable in high temperatures (400°C) as well as effective in high water mobile phases. Phenyl moieties of the material provide increased and sometimes excessive retention of analytes with pi-systems occurred in …

Microstructure Studies In Synthetic And Bio-Colloids, Imaging And Applications, Ashish Kumar Jha

Open Access Dissertations

The mean size of CTAB/HDBS mixed surfactant vesicles confined into the three-dimensional voids generated by the random close packing (RCP) of polystyrene beads, shows a systematic decrease as the characteristic confinement length scale is reduced. The RCP of polystyrene beads of radius Rb = 1.5μm, 0.25μm and 0.1μm, creates voids of characteristic dimensions R ∼ 0.22 Rb = 3300Ã…, 550Ã… and 220Ã… respectively. These void length scales are comparable to or less than the radii of vesicles formed in the system under conditions of no confinement. A simple thermodynamic model was developed accounting for the balance between increased enthalpy when …

Fabrication, Characterization And Application Of The Novel Bionanomaterials, Lan Yao

Open Access Dissertations

This dissertation focuses on developing methods to synthesize novel bionanomaterials, studying their properties and exploring their potential applications. Fabricating semiconducting nanowires is a significant challenge in making nanoscale electronic devices. We propose to use self-assembling biomolecules as templates for the fabrication of nanowires. Here we demonstrate that quantum dots (QDs) could be conjugated to actin filaments, forming long semiconductor filaments. We constructed an optical system and developed the interactive software for fluorescence anisotropy imaging of single QDs and QD-nanowires. The fluorescence anisotropy studies revealed that QD transition dipoles are likely circular (elliptical) dipoles. The fluorescence anisotropy of a single QD …