Physical Sciences and Mathematics Commons^™

Model-Based Imputation Of Below Detection Limit Missing Data And Group Selection In Bayesian Group Index Regression, Matthew Carli

Theses and Dissertations

Investigations into the association between chemical exposure and health outcomes are increasingly focused on the role of chemical mixtures, as opposed to individual chemicals. The analysis of chemical mixture data required the development of novel statistical methods, one of these being Bayesian group index regression. A statistical challenge common to all chemical mixture analyses is the ubiquitous presence of below detection limit (BDL) data. We propose an extension of Bayesian group index regression that treats both regression effects and missing BDL observations as parameters in a model estimated through a Markov Chain Monte Carlo algorithm that we refer to as …

Beyond The Green Iron Cage: Exploring The Macro And Micro-Level Influences On Executive Decisions About Sustainability Investments In Small And Medium Size Firms, Igor Estraykh

Theses and Dissertations

Although research on corporate environmental sustainability has shed light on different aspects of organizational and individual level factors that influence corporate decisions, it does not fully account for how individual executives within firms react to these forces and make decisions, specifically within small to medium size enterprises (SMEs). This study used a grounded theory approach to interview 19 SME executives from 13 different industries to explore how organizational and individual level factors influence their ability to evaluate and make decisions related to sustainability initiatives. The study found that SME executives faced isomorphic pressures for sustainability, individual agency pressures, significant resource …

Fate Of Persistent Contaminants And Emerging Algal Toxins In Drinking Water And The Environment, Danielle Christine Westerman

Theses and Dissertations

Population growth and global climate change has resulted in the degradation of pristine water sources, causing issues like saltwater intrusion, persistent harmful algal blooms, and drought from population growth. Future reliance on alternative sources of drinking water to is expected globally, therefore, nontraditional sources of drinking water are becoming increasingly vital sources of potable water around the world. For example, desalination (typically by reverse osmosis), despite its high energy demands and high cost, is being utilized all over the world to meet drinking water demand. Wastewater reuse, the additional treatment of wastewater to produce drinking water, either directly or indirectly, …

Assessing The Impact Of Incorporating Residential Histories Into The Spatial Analysis Of Cancer Risk, Anny-Claude Joseph

Theses and Dissertations

In many spatial epidemiologic studies, investigators use residential location at diagnosis as a surrogate for unknown environmental exposures or as a geographic basis for assigning measured exposures. Inherently, they make assumptions about the timing and location of pertinent exposures which may prove problematic when studying long latency diseases such as cancer.

In this work we explored how the association between environmental exposures and disease risk for long-latency health outcomes like cancer is affected by residential mobility. We used simulation studies conditioned on real data to evaluate the extent to which the commonly held assumption of no residential mobility 1) affected …

Modeling Spatially Varying Effects Of Chemical Mixtures, Jenna Czarnota

Theses and Dissertations

Cancer incidence is associated with exposures to multiple environmental chemicals, and geographic variation in cancer rates suggests the importance of accommodating spatially varying effects in the analysis of environmental chemical mixtures and disease risk. Traditional regression methods are challenged by the complex correlation patterns inherent among co-occurring chemicals, and the applicability of geographically weighted regression models is limited in the setting of environmental chemical risk analysis. In comparison to traditional methods, weighted quantile sum (WQS) regression performs well in the identification of important environmental exposures, but is limited by the assumption that effects are fixed over space. We present an …

Further Development Of A Model Of Environmental Commitment, Shane Boyd

Theses and Dissertations

Environmental commitment is a concept based on the investment model and interdependence theory literature. Interdependence theory and the investment model were originally geared towards the study of relationship commitment as function of relationship satisfaction and alternatives to being in that relationship. It has since been applied to areas outside of relationship commitment such as environmental commitment. Previous research has demonstrated that environmental commitment can be predictive of environmental behavior, above and beyond several different control variables that captured different aspects of the person-environment relationship (Davis, Le, & Coy, 2011; Davis, Green, & Reed, 2009). This project will strengthen the existing …

Determination Of Size Fractions And Concentrations Of Airborne Particulate Matter Generated From Construction And Demolition Waste Processing Facilities, Jason M. Young

Theses and Dissertations

Construction and Demolition (C&D) processing and recycling facilities accept waste materials that are generated during construction and demolition activities. The processing facility sorts, processes, and transfers the material to another operation. A consequence of these processes is the generation of particulate matter.This study involved quantifying and qualifying airborne particulates at three C&D processing facilities. Active stationary particulate sampling devices were employed to quantify the particle sizes of interest. Results were compared to United States Environmental Protection Agency (EPA) National Ambient Air Quality Standards(NAAQS) and United States Occupational Safety and Health Administration (OSHA)standards.The results from this study are not valid for …