Public Health Commons^™

Gis Automated Delineation And Analysis Of Cancer Service Areas In The United States, Changzhen Wang

LSU Doctoral Dissertations

Delineating a meaningful and reliable geographic unit pertaining to cancer care is essential in examining geographic variations in cancer care for better analysis, management, and planning. Public health researchers have devoted great efforts to defining various service areas, which; however, lack scientific rigor or are unrepresentative of the highly specialized cancer care markets, and their methods have become obsolete in the era of big data and high geo-computation. This study develops the “Spatially Constrained Leiden (ScLeiden)” method, a network community detection algorithm in Geographic Information Systems (GIS), and applies it to delineate a series of coherent cancer service …

Characterizing Middle School Students’ Physical Literacy: A Sequential Mixed Methods Study, Yang Liu

LSU Doctoral Dissertations

The purpose of this dissertation study was (a) to characterize middle school students’ levels of physical literacy (PL) and PL domains by gender, grade, socioeconomic status (SES), weight status, race, and ethnicity; and (b) to capture PL trajectory change as a result of receiving a theory-informed pedagogical workshop. Participants (N = 350) in sixth and seventh grades were recruited from a public middle school located in a southeastern U.S. state. These students completed the second version of the Canadian Assessment of Physical Literacy (CAPL-2). A subsample (n = 49) received a pedagogical workshop (four sessions over eight weeks), …

Towards Optimizing Quality Assurance Outcomes Of Knowledge-Based Radiation Therapy Treatment Plans Using Machine Learning, Phillip Douglas Hardenbergh Wall

LSU Doctoral Dissertations

Knowledge-based planning (KBP) techniques have been shown to provide improvements in plan quality, consistency, and efficiency for advanced radiation therapies such as volumetric modulated arc therapy (VMAT). While the potential clinical benefits of KBP methods are generally well known, comparatively less is understood regarding the impact of using these systems on resulting plan complexity and pre-treatment quality assurance (QA) measurements, especially for in-house KBP systems. Therefore, the overarching purpose of this work was to assess QA implications with using an in-house KBP system and explore data-driven methods for mitigating increased plan complexity and QA error rates without compromising dosimetric plan …

Stray Radiation Dose From X-Ray And Proton Beam Radiation Therapies, Christopher William Schneider

LSU Doctoral Dissertations

The growing population of cancer survivors at risk of radiation induced side-effects is a public health concern. These side-effects include serious conditions such as second cancers, the majority of which occur outside of the primary treatment volume. Radiotherapy treatment planning systems systematically underestimate the dose to tissues out-of-field. Attempts to predict and reduce the risks of radiogenic side effects require accurate and personalized knowledge of the out-of-field radiation dose to patients. The long-term goal of this research is to provide clinical and research tools necessary to reduce the risk of radiotherapy side effects and improve the health outcomes of radiotherapy …

The Use Of Geospatial Modeling And Novel Diagnostics To Detect And Map Risk Factors Of Soil-Transmitted Helminths In Feira De Santana, Brazil, Ryan Harry Avery

LSU Doctoral Dissertations

Soil-transmitted helminth (STH) infections impact billions of people worldwide. The traditional STH control approach is a morbidity control strategy implementing mass drug administration (MDA) programs targeting school-aged children (SAC). In Brazil, this control strategy has decreased STH prevalence to less than 20% in most of the country and providing an opportunity to transition from the morbidity control program and towards a surveillance and response system geared towards STH elimination. Surveillance and response systems geared towards elimination require the implementation higher accuracy diagnostics to detect infection in low-transmission communities, surveillance of entire households, high-resolution modeling at the household-habitat scale, and targeted …

Computational Feasibility Of Simulating Whole-Organ Vascular Networks And Their Response To Injury, William Patrick Donahue

LSU Doctoral Dissertations

Healthy vasculature is critical to sustaining the function of normal tissues in the human body. Radiation therapy for cancer causes injury of the vasculature of non-cancerous tissues. These changes have been associated with potentially deadly conditions such as necrosis of the brain tissue. There are currently no computational methods to study the effects of radiation vascular injury in whole-organ vasculatures because of the large number of vessels involved. The goal of this work was to test the feasibility of simulating radiation damage to whole-brain vascular networks and calculate the resulting change in blood flow. To accomplish this, we developed algorithms …

A Case-Study Approach To Investigate Transmission, Co-Infection, And Clinical Sequelae During Epidemics Of Dengue And Ebola Virus Disease, Jennifer Elizabeth Giovanni

LSU Doctoral Dissertations

From within their ecologic niches, zoonotic viruses emerge from animal reservoirs into the edges and centers of human habitation to exploit opportunities for unabated transmission within immunologically–naïve populations. Our understanding of where, in whom, and how these viruses emerge is under direct challenge, driving the evolution of modern infectious disease epidemiology within a rapidly-connected global community. The studies presented herein are based on analyses of both aggregate and case-level data, which, we argue, provide unique insight into the complexities of transmission, co-infection, and clinical sequelae occurring within, and arising from, epidemics of emerging zoonotic viruses. In Chapter II, we investigate …

Framework For Algorithmically Optimizing Longitudinal Health Outcomes: Examples In Cancer Radiotherapy And Occupational Radiation Protection, Lydia Joyce Wilson

LSU Doctoral Dissertations

Background: Advancements in the treatment of non-infectious disease have enabled survival rates to steadily increase in recent decades (e.g., diabetes, heart disease, and cancer). Epidemiological studies have revealed that the treatments for these diseases can have life-threatening and/or life–altering effects. Thus, realizing the full beneficial potential of advanced treatments necessitates new tools to algorithmically consider all major components of the health outcome, including benefit and detriment. The goal of this dissertation was to develop a framework for improving projected health outcomes following planned radiation exposures in consideration of all beneficial and detrimental, early and late, and fatal and non-fatal …

Use Of A Behavioral Health Framework To Assess Perceptions Of Hurricane Evacuation Support Services In New Orleans, Louisiana, Aubry Kyle

LSU Doctoral Dissertations

This dissertation presents research conducted during the hurricane seasons of 2017 and 2018 in New Orleans, Louisiana. The research’s purpose was to assess citizen perceptions of evacuation support services offered during mandatory evacuation events. A prospective quantitative survey and qualitative, open-ended, semi-structured interview assessed perceptions. Both research methods were designed and assessed using the constructs of the Health Belief Model, a public health model created to assess perceived barriers, benefits, risks, severity, self-efficacy, and cues to action regarding health programming. Quantitative research yielded 211 surveys, representing opinions of New Orleans residents within 1-km Euclidian distance of an evacuation pick-up marker. …

Development, Validation, And Testing Of A Self-Determination Theory Instrument Called The Motivation To Prepare Healthy Foods Questionnaire, Ariana Delong Bailey

LSU Doctoral Dissertations

The objectives of these studies were to validate and confirm the structure of a previously developed questionnaire that measures the psychosocial constructs defined by the Self-Determination Theory (SDT) and then test this questionnaire in a nutrition education setting. The instrument, titled the Motivation to Prepare Healthy Foods Questionnaire (MPHFQ), included items that measured intrinsic motivation, perceived competence, relatedness, autonomy, and autonomy support. These studies evaluated the questionnaire’s validity and ability to measure changes in the SDT construct scores.

The MPHFQ is a previously developed and reliable instrument intended to measure adults’ intrinsic motivation and perceived competence to prepare healthy foods, …

Healthcare Utilization & Health Behaviors Among Older Adults: The Role Of Insurance, Jennifer Rose Geiger

LSU Doctoral Dissertations

As the population of older adults in the U.S. continues its exponential growth, so too will the need for high-quality health and preventive services. Despite the widely acknowledged need for proactive solutions to the coming public health challenges for this rapidly expanding age cohort, healthcare providers and social work practitioners continue to lack the proper education training to serve the needs of older adults. Furthermore, these allied health professionals also frequently engage in ageist behaviors across care settings that also often employ institutionally ageist policies and procedures. As a result, older adults may be particularly at risk of negative health …

Endorectal Digital Prostate Tomosynthesis, Joseph Robert Steiner

LSU Doctoral Dissertations

Several areas of prostate cancer (PCa) management, such as imaging permanent brachytherapy implants or small, aggressive lesions, benefit from high image resolution. Current PCa imaging methods can have inadequate resolution for imaging these areas. Endorectal digital prostate tomosynthesis (endoDPT), an imaging method that combines an external x-ray source and an endorectal x-ray sensor, can produce three-dimensional images of the prostate region that have high image resolution compared to typical methods. This high resolution may improve PCa management and increase positive outcomes in affected men.

This dissertation presents the initial development of endoDPT, including system design, image quality assessment, and examples …

Development And Applications Of A Real-Time Magnetic Electron Energy Spectrometer For Use With Medical Linear Accelerators, Paul Ethan Maggi

LSU Doctoral Dissertations

Purpose – This work presents a design for a real-time electron energy spectrometer, and provides data analysis methods and characterization of the real-time system. This system is intended for use with medical linear accelerators (linacs). The goal is 1 Hz acquisition of the energy range 4-25 MeV, reconstructed in 0.1 MeV increments.

Methods – Our spectrometer uses a nominal 0.54 T permanent magnet block as the dispersive element and scintillating fibers coupled to a CCD camera as the position sensitive detector. A broad electron beam produced by a linac is collimated by a 6.35 mm dimeter aperture at the entrance …