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Natural Radioactivity In Groundwater, Rocks And Sediments From Some Areas In The Uae: Distribution, Sources And Environmental Impact, Dalal Matar Al Shamsi

Dissertations

Groundwater contains a certain amount of natural radioactivity that generally results from the decay of uranium, thorium and ⁴⁰K isotopes. Knowledge of concentration levels, spatial distribution and sources of these isotopes in groundwater is crucial for environmentally safe and sustainable groundwater resources in the United Arab Emirates (UAE). This dissertation focuses on investigating the distribution, environmental impact and sources of ²³⁵U, ²³⁸U, ²³²Th, as well as the activity of gross β and α in groundwater in some locations in the UAE. Additionally, groundwater samples from Oman and selected aquifer rocks and sediments from the UAE were …

Hypoxic Signals In The Ischemic Myocardium: Role Of Galectin-1 And Galectin-3, Satwat Hashmi

Dissertations

Myocardial infarction is the most serious manifestation of coronary artery disease and the cause of significant levels of mortality and morbidity worldwide. Galectin-1 (GAL-1) and Galectin-3 (GAL-3) are beta galactoside binding lectins with diverse functions. Hypoxia inducible factor-1 alpha (HIF-1α) is a transcription factor mediating early and late responses to myocardial ischemia. We aim to study the direct effects of ischemia on GAL-1, GAL-3 and HIF-1α in the heart. Male C57B6/J and GAL-3 knockout mice were used for our two disease models. In the Myocardial infarction (MI) model, the left anterior descending artery of the heart is permanently ligated to …

Identification Of Novel Natural Compounds With Anti-Breast Cancer Activities, Yusra Saif Al Dhaheri

Dissertations

Breast cancer continues to be the leading cause of cancer-related death in women worldwide. In this dissertation, natural compounds with anti-breast cancer activities were identified. We investigated the effect of Salinomycin, a potassium ionophore isolated from Streptomyces albus, on the survival of three human breast cancer cell lines MCF-7, T47D and MDA-MB-231. High concentrations of Salinomycin induced a G2 arrest, down regulation of survivin and triggered apoptosis. Interestingly, treatments with low concentrations of Salinomycin induced a transient G1 arrest at an earlier time and G2 arrest and senescence, associated with enlarged cell morphology, at a later time. There was also …

Effects Of The Endocannabinoid Anandamide On Excitability And Calcium Signaling In Rat Ventricular Myocytes, Lina Tareq Al-Kury

Dissertations

Endogenous cannabinoids (endocannabinoids) exert a wide range of biological effects. In addition to having their well-known neurobehavioral effects, a role for the major endocannabinoid anandamide (N-arachidonoyl ethanolamide; AEA), in the cardiovascular system in various pathological conditions has been reported. The aim of this thesis is to explore the effects of AEA on contractility, Ca2+ signaling, and action potential (AP) characteristics in rat ventricular myocytes. A video edge detection system was used to measure myocyte shortening. Intracellular Ca2+ was measured in cells loaded with the fluorescent indicator fura-2 AM. AEA (1 μM) caused a significant decrease in the amplitude of electrically-evoked …

A Beacon Of Light: Tougaloo During The Presidency Of Dr. Adam Daniel Beittel (1960-1964), John Gregory Speed

Dissertations

This study examines leadership efforts that supported the civil rights movements that came from administrators and professors, students and staff at Tougaloo College between 1960 and 1964. A review of literature reveals that little has been written about the college‘s role in the Civil Rights Movement during this time. Thus, one goal of this study is to fill a gap in the historical record.

A second purpose of this study is to examine the challenges of progressive leadership at a historically Black college in Mississippi during the Civil Rights Movement when a White president was at the helm.

When Dr. …

The Effects Of Leadership And High-Stakes Testing On The Retention Of Teachers, Amy Krohn Thibodeaux

Dissertations

The purpose of this study was to examine whether principal leadership behaviors and the demands of high-stakes tests had an impact on teachers’ intent to remain in the teaching profession. Perceptions of teachers concerning the contributing factors that led to their intent to remain in the teaching profession were also examined. Factors included in this study were examined by the researcher in an effort to gain knowledge of what leads to teacher job satisfaction in the teaching profession.

The researcher used a quantitative survey instrument with a qualitative component. The survey instrument was created by the researcher and consisted of …

Comparison Of The Conceptual Understanding Of Newton's Laws In An Online And Traditional Introductory Physical Science Course, Rex Robert Moak

Dissertations

The purposes of this study were to (a) determine if taking the Physical Science Survey I course in face-to-face (F2F) and online format statistically significantly improves Newtonian conceptual comprehension as measured by the FCI; (b) determine which course format, if any, has statistically significantly higher FCI post-means; and (c) determine if students’ satisfaction with learning is statistically significantly different in the two course formats.

Data for this study was collected from students and faculty in various course formats during the Fall semester of 2012 and the Spring semester of 2013. The researcher used two research tools: the Force Concepts Inventory …

Race, Gender, And Faculty Advancement At American Colleges And Universities, James Sharell Bridgeforth

Dissertations

Women and people of color are underrepresented in the American professoriate; although the presence of female faculty and professors of color is beneficial to the academy on various levels, these groups often face many barriers and challenges throughout the promotion and tenure process. This study was designed to examine whether race, gender, or a combination of race and gender made a statistically significant difference in reported opportunities for mentorship, faculty socialization, and scholarship in regard to faculty advancement in the academy. Data were collected from 650 tenured and tenure-track faculty through an online questionnaire. The data analysis revealed that women …

The Delivery, Speciation, And Fate Of Trace Elements In St. Louis Bay, Mississippi, Gopal Bera

Dissertations

Estuaries are dynamic regions in which there can be significant modification of the riverine flux of trace elements to the open ocean due to various geochemical, physical, and biological processes. Additionally, estuaries are often subject to anthropogenic inputs of trace elements. The first portion of this study investigated the source, behavior, and sediment interaction of anthropogenic stable cesium (Cs) in St. Louis Bay (SLB), MS. A consistent increase in stable Cs concentration was noticed in sediment cores starting from a period when a titanium dioxide refinery on SLB started operations. Weak correlation between Cs and clay percentage and strong correlations …

Relationship Between Leadership Styles Of High School Teachers, Principals, And Assistant Principals And Their Attitudes Toward School Wide Positive Behavior And Support Implementation, Geneva Cosweller Lampton-Holmes

Dissertations

The purpose of this study was to determine if seventh through twelfth grade educators’ attitudes towards School-Wide Positive Behavior Support (SWPBS) are affected based on their gender, years of experience, school discipline policy, leadership style, and knowledge of SWPBS.

Through an online survey, an analysis of the leadership style and knowledge of SWPBS of Mississippi teachers and administrators was conducted. Other variables included the school discipline policy and participants’ gender and years of experience. The study found that knowledge of SWPBS and school discipline policy had a significant impact on the educators’ attitudes towards SWPBS. Leadership style, gender, and years …

Biogeochemistry Of Trace Elements In The Mixing Zone Of The Mississippi And Atchafalaya Rivers And Chemical Distributions As Affected By The Deepwater Horizon Blowout, Dongjoo Joung

Dissertations

Selected trace elements (TEs), dissolved organic carbon, and nutrients were studied in Louisiana Shelf waters including the Mississippi (MR) and Atchafalaya (AR) River plumes during periods of high, intermediate, and low river discharges. Seasonal variations in TEs were observed at low salinity, reflecting seasonal changes in the river water endmembers. Shelf surface water dissolved Mo, Cs, U, Ni, and Cu showed conservative behavior with minor scattering in some high salinity waters. Based on associated mixing experiments, nutrient and chlorophyll distributions, as well as surface-bottom concentration contrasts, the non-conservative behavior of TEs was variously related to colloidal flocculation (Fe, Cr), biological …

Oxidative Stress Alterations Following An Exercise Intervention In Cancer Survivors, Christopher P. Repka

Dissertations

Exercise interventions in cancer patients have been demonstrated to reduce cancer-treatment related side effects. Despite this, the underlying mechanisms associated with the protective aspects of exercise are generally uncharacterized, but treatment-associated oxidative stress is thought to play a role. The purpose of this study was to determine the effect of an exercise intervention on fatigue, cardiorespiratory fitness (CRF), muscular strength, and blood markers of DNA and protein oxidation compared to a non-exercising, cancer control group. METHODOLOGY: An initial fasting blood draw and assessments of muscular strength and CRF were administered to fifteen cancer patients within six weeks of completing radiation …

Exploring Students' Perceptions And Performance On Predict-Observe-Explain Tasks In High School Chemistry Laboratory, Praveen Vadapally

Dissertations

This study sought to understand the impact of gender and reasoning level on students’ perceptions and performances of Predict-Observe-Explain (POE) laboratory tasks in a high school chemistry laboratory. Several literature reviews have reported that students at all levels have not developed the specific knowledge and skills that were expected from their laboratory work. Studies conducted over the last several decades have found that boys tend to be more successful than girls in science and mathematics courses. However, some recent studies have suggested that girls may be reducing this gender gap. This gender difference is the focal point of this research …

Schools Are Very Different Here: Somali Refugees' Perspectives Of Parent Involvement, Mary L. Van Korlaar

Dissertations

Qualitative case study with participant observation was used to explore the parent involvement experiences of nine Somali refugee parents in a small city in an agricultural area of the Rocky Mountain region. The parents of students who were attending classes through a school-based Welcome Center program were invited to participate. Parents were asked to discuss their own educational background, and their experiences prior to immigration to the United States in an effort to understand the development of their understanding, values and beliefs about education. Parents were also asked about their experiences in the local school systems to better understand their …

An Exponentiality Test Using A Modified Lilliefors Test, Achut Prasad Adhikari

Dissertations

No abstract provided.

A Phenomenological Study Of Acceptability Of Preexposure Prophylaxis Therapy Within The Lived Experiences Of Hiv Negative Male-To-Female Transgender Young Adults, Gloria N. Nwagwu Phd

Dissertations

The male-to-female transgender (MtF-TG) are individuals assigned a male gender at birth but self identify as female. MtF-TG young adults experience discrimination, stigmatization, isolation, and homelessness as a result of gender identity and gender expression. The transgender populations are linked to high rate of new HIV infection. The use of Preexposure prophylaxis (PrEP) therapy demonstrated a decrease in HIV infection risk ranging from 42% to 73% among sexual minority individuals. The goal of this three-part study was achieved through concept analysis, data collection, and analysis. The following aims were addressed; analyze the concept of transgender, explore currently used HIV prevention …

Identification Of Posttraumatic Stress Disorder Symptoms In Post-Icu Patients, Heather Warlan Phd, Rn, Ccrn

Dissertations

Background: Patients receiving critical care are experiencing post-traumatic stress syndrome (PTSS) as a result of life-saving interventions received in the intensive care unit (ICU). PTSS is associated with poor patient outcomes and decreased quality of life compared to post-ICU patients without PTSS. Personal and clinical characteristics that place patients at higher risk for PTSS are still being examined. It is also unknown to what extent patients are being screened for ICU-induced PTSS. Objectives: This body of work aims to examine the risk factors associated with ICU-related PTSS and describe the screening experiences of patients who recently received care in an …

"Parent Trigger" Legislation In The United States: A Key To Parent Empowerment In The Local Context, Julie A. Zoellin Cramer Phd

Dissertations

Parent involvement in public education has changed over time in the United States. Recently it has taken on a more radical dimension aimed at shifting the role of parents. These efforts are identified by some as parent empowerment and arguably may be part of a larger policy movement to secure parent voice in equity-focused education reform. The policy innovation allows parents with students in persistently underperforming schools to force a change in school governance. Since the passage of the first parent trigger law in California in 2010, three parent petition campaigns have forced a turnaround in school governance. The purpose …

We Are Not Mahogany An Exploration Of The Social Construction Of Masculinity In Ugandan Meaning-Making, Nathaniel P. Dunigan Phd

Dissertations

In the study of both economic and human development, the men of the global South [sic] are often considered to be responsible for the lack of progress and for the lack of human flourishing. An abundance of literature exists exploring how women and children make meaning in the global South with many clear indicators that the choices made by men in their lives have led to an overall sense of need and a lack of wellness. Attempting to better understand how men of different cultures make sense of their world and navigate their life experiences can only enhance strategies in …

Central And Secondary Struggles In Social Interventions: The Impact Of Group Relations Learning On Real Life Practices, Ole-Kristian Setnes Phd

Dissertations

Recently, there has been considerable research focusing on outcomes of Group Relations conferences as a unique form of adult experiential learning. Most of the focus has been on participants' learning during and immediately after conferences with less attention paid to applications of learning outside conferences in participants' professional and/or personal lives. The San Diego group relations/ case-in-point model is integrated into the University of San Diego's graduate leadership studies program. Participants in this study included 10 individuals who had participated in this model's experiential learning as teaching assistants. The methodology that was implemented, Relational Qualitative Research, synthesizes elements from several …

A Sleep Apnea Program For Commercial Drivers, Gayla Ann Dace

Dissertations

Sleepy driving is a major contributing factor to the motor vehicle crash risk associated with commercial drivers (Pack et al., 2006). In commercial vehicles, approximately 31% to 41% of major crashes can be linked to sleepy driving (Gurubhagavatula et al., 2004). An average non-fatality crash involving a commercial motor vehicle costs about $75,637 while a fatality crash averages about $3.54 million (Gurubhagavatula et al., 2004). A contributing factor to sleepy driving is obstructive sleep apnea (Pack et al., 2006). The purposes of this study were to: (1) determine how many commercial motor vehicle drivers referred to a sleep center as …

Dynamics Of Phase Locking In Neuronal Networks In The Presence Of Synaptic Plasticity, Zeynep Akcay

Dissertations

The behavior generated by neuronal networks depends on the phase relationships of its individual neurons. Observed phases result from the combined effects of individual cells and synaptic connections whose properties change dynamically. The properties of individual cells and synapses can often be characterized by driving the cell or synapse with inputs that arrive at different phases or frequencies, thus producing a feed-forward description of these properties. In this study, a recurrent network of two oscillatory neurons that are coupled with reciprocal synapses is considered. Feed-forward descriptions of the phase response curves of the neurons and the short-term synaptic plasticity properties …

Processing And Characterization Of Innovative Magnesium Alloys For Biodegradable Orthopaedic Implants, Christopher E. Smith

Dissertations

There is a need for innovation in medical implant devices through novel biomaterials that will improve the quality of life. The first step in the creation of a foundation of knowledge and technology to improve these implant devices is through the creation of new alloys with the capabilities of biodegradation and bioabsorption without a toxic effect that will pass through FDA regulatory procedures. In this study, unique heat treatment processing techniques coupled with innovation in elemental alloying produced distinctive magnesium (Mg) based alloy systems. The MgZnCa system was used as the underpinning system where four groups of novel alloys were …

A Phenomenological Study Into How Students Experience And Understand The University Presidency, Kahler B. Schuemann

Dissertations

Little is known about how college students experience and understand the university presidency. Students are important consumers of the academic experience and by affiliation are constituents of organizational leadership. The social distance between students and university presidents continues to narrow. To address the void in scholarly literature, my study explored how students experience and understand the university presidency.

My investigation utilized phenomenological methodology to form descriptive themes. I interviewed 10 college students who self-identified as being involved with extracurricular activities and having, at minimum, occasional interaction with their president. Participants were selected from two small, public, Midwestern universities where their …

Synthesis, Characterization And Potential Applications Of Palladium And Ruthenium Nanostructures, Clara Patrice Adams

Dissertations

Controlling the size and shape of metal nanostructures is important for tuning the intrinsic chemical and physical properties of materials, and consequently their potential technological applications. Modulating the morphology of metal nanostructures is essential to understanding the structure-function relationship (for example, optical, magnetic, catalytic, and electronic properties) under various environmental conditions. Our work describes the development of new procedures for the synthesis of well-defined isotropic and anisotropic nanoparticles consisting of palladium (Pd) and ruthenium (Ru). Characterization of the nanostructures was carried out using transmission electron microscopy (TEM), high resolution-TEM (HRTEM), powder x-ray diffraction (XRD), selected area electron diffraction (SAED) and …

Size-Dependent Interactions Of Metal Nanoparticles With Fluorophores And Semiconductors, Liyana A. Wajira Ariyadasa

Dissertations

In recent years, nanoscale metallic particles have gained considerable interest due to their potential applications in advanced technology. Despite such interest, synthetic procedures that produce gram-scale, well-defined metallic nanoparticles with controlled size and shape, especially with diameters less than 5 nm remains a challenge. Our work has focused on developing synthetic procedures that produce well-defined platinum and palladium metal nanoparticles in the 1-5 nm size range. Thioether ligands were used as stabilizers and resulted in metal nanoparticles with controlled size. The nanoparticles were characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), selected area electron diffraction (SAED), x-ray photoelectron spectroscopy …

Fundamental Studies Of Protein Ionization For Improved Analysis By Electrospray Ionization Mass Spectrometry And Related Methods, Kevin A. Douglass

Dissertations

Mass spectrometry (MS) is an analytical technique in which a sample is converted to gas-phase ions that are subsequently separated and detected. It offers great speed, selectivity, and sensitivity during analysis, characteristics which have enabled it to become a leading method for the study of proteins. The applications of MS for these biologically significant macromolecules range from accurately determining identity and sequence to shedding light on post-translational modifications and protein-molecule interactions. As a first step towards analysis by MS, gas-phase protein ions must be formed. A common method for ionization is electrospray ionization (ESI), where a liquid sample including the …

Gdnf Content And Nmj Plasticity In Slow And Fast Twitch Myofibers Follows Recruitment In Exercise, Amy Morrison Gyorkos

Dissertations

Glial cell-line derived neurotrophic factor (GDNF) supports and maintains the neuromuscular system during development and through adulthood by promoting neuroplasticity. GDNF may play a role in delaying the onset of aging and help compress morbidity by preventing motor unit degeneration. Exercise has been shown to alter GDNF expression differently in slow and fast twitch myofibers. The aim of this dissertation project is to determine if different intensities of exercise can promote changes in GDNF expression and neuromuscular junction (NMJ) morphology in slow and fast twitch muscle fibers. Skeletal muscle fibers were analyzed from adult Sprague Dawley rats aged 4 weeks …

Impulsive Choice In Unmedicated And Medicated Children Diagnosed With Adhd: Examining The Variables Of Reward Type And Adhd Subtype, Nicole Henriksen

Dissertations

Developmentally inappropriate and impairing impulsive behaviors are often seen in attention-deficit/hyperactivity disorder (ADHD). One method for objectively assessing impulsivity is the Choice-Delay Task (C-DT) which presents repeated opportunities to choose between a smaller, sooner (SS) or larger, later (LL) reward. A preference for the SS reward that results in less total reward is considered impulsive. Many studies have found that participants diagnosed with ADHD choose the SS reward more than typical controls. However, less is known about the effects of different types of rewards, or the comparative performance of certain subgroups, such as children diagnosed with ADHD Predominantly Inattentive Type …

The Intersection Of Depression, Partner Violence And Poverty During The Perinatal Period, Catherine L. Kothari

Dissertations

Problem: Despite the wealth of research documenting the individual links between maternal depression, partner violence, and poverty, important gaps remain regarding their combined interactions, and their variation related to perinatal timing (pregnancy and postpartum). The current dissertation examined the interplay of these phenomena across perinatality.

Methods: This dissertation utilized secondary analysis of telephone survey data from a representative sample of women recruited during their postpartum hospital stay and interviewed four times over the subsequent 18 months. Linear regression was used for predictive modeling of fixed effects, and generalized estimating equation regression was used for multivariate analysis of temporal trends.

Findings: …