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Full-Text Articles in Epidemiology

Evaluation Of The Survival Effect For Various Treatment Modalities Among Stage Ii And Iii Rectal Cancer Patients In California, 1994-2009, Myung Mi Cho Dec 2012

Evaluation Of The Survival Effect For Various Treatment Modalities Among Stage Ii And Iii Rectal Cancer Patients In California, 1994-2009, Myung Mi Cho

Loma Linda University Electronic Theses, Dissertations & Projects

Background: European trials evaluating the effect of preoperative (PreOP) versus postoperative chemoradiotherapy (PostOP CRT) found no survival benefit. However, the effect of a change from PostOP to PreOP CRT has not been evaluated in a population-based setting. We sought to evaluate multimodal treatment changes and overall survival for perioperative (PeriOP) CRT versus surgery alone and for PreOP versus PostOP CRT from 1994 through 2009 among patients receiving radical surgery for stage II and III rectal cancer (RC).

Patients and Methods: We conducted a nonconcurrent cohort study evaluating demographic predictors of multimodal therapy for stage II and III RC using …


Complexity And Uncertainty In Human And Ecological Risk Assessment, Matthew Jordan Dellinger Dec 2012

Complexity And Uncertainty In Human And Ecological Risk Assessment, Matthew Jordan Dellinger

Theses and Dissertations

Multiple interacting stressors in the environment present increasingly complex risks to human health. Too often, however, the data required for traditional risk assessment are either lacking or unavailable at the necessary spatial or temporal scale. In addition, assessment practices and management policies need to move away from single factor approaches in order to accommodate the reality of complex chemical mixtures and environmental stressors. Recent literature suggests that a paradigm shift is under way. This points to a need for the development of new techniques both for rapid data collection and flexible risk assessment strategies that can adapt to make use …


Latin Hypercube Sampling And Partial Rank Correlation Coefficient Analysis Applied To An Optimal Control Problem, Boloye Gomero Aug 2012

Latin Hypercube Sampling And Partial Rank Correlation Coefficient Analysis Applied To An Optimal Control Problem, Boloye Gomero

Masters Theses

Latin Hypercube Sampling/Partial Rank Correlation Coefficient (LHS/PRCC) sensitivity analysis is an efficient tool often employed in uncertainty analysis to explore the entire parameter space of a model. Despite the usefulness of LHS/PRCC sensitivity analysis in studying the sensitivity of a model to the parameter values used in the model, no study has been done that fully integrates Latin Hypercube sampling with optimal control analysis.

In this thesis, we couple the optimal control numerical procedure to the LHS/PRCC procedure and perform a simultaneous examination of the effects of all the LHS parameter on the objective functional value. To test the effectiveness …


Constrained Optimal Control For A Multi-Group Discrete Time Influenza Model, Paula Andrea Gonzalez Parra Jan 2012

Constrained Optimal Control For A Multi-Group Discrete Time Influenza Model, Paula Andrea Gonzalez Parra

Open Access Theses & Dissertations

During the last decades, mathematical epidemiological models have been used to understand the dynamics of infectious diseases and guide public health policy. In particular, several continuous models have been considered to study single in uenza outbreaks and the impact of dierent control policies. In this dissertation, a discrete time model is introduced in order to study optimal control strategies for in uenza transmission; since epidemiological data is collected on discrete units of time, a discrete formulation is more ecient. From a mathematical point of view, continuous time model are easier to analyze, however, the numerical solution of discrete-time models is …


Evaluating Retention In Medical Care And Its Impact On The Health Outcomes Of Individuals Living With Human Inmmunodeficiency Virus, Timothy N. Crawford Jan 2012

Evaluating Retention In Medical Care And Its Impact On The Health Outcomes Of Individuals Living With Human Inmmunodeficiency Virus, Timothy N. Crawford

Theses and Dissertations--Epidemiology and Biostatistics

In the last few years, engagement in medical care among individuals living with HIV has become a major priority among HIV medical providers and public health researchers. Engagement in medical care is an important concept as it involves the process of linking newly diagnosed individuals into medical care and retaining those individuals in care throughout the course of their infection. Although there have been major advances in the management of HIV, like the advent of Highly Active Antiretroviral Therapy, morbidity and mortality due to HIV cannot be fully reduced if the individual does not optimally retain in care. Retention in …


The Association Of Summer Temperatures With Hospital Admissions For Renal Diseases In New York State : A Case-Crossover Study, Barbara A. Fletcher Jan 2012

The Association Of Summer Temperatures With Hospital Admissions For Renal Diseases In New York State : A Case-Crossover Study, Barbara A. Fletcher

Legacy Theses & Dissertations (2009 - 2024)

This study assessed the association between high temperatures and increased odds of hospitalization for renal diseases which, to date, has been examined in only a small number of studies. A case-crossover design was used to study 147,885 hospital admissions with renal diagnoses during July and August, 1991-2004 in New York State. Regional temperature, humidity and barometric pressure data from automated monitors were used as exposure indicators. Using time-stratified referent selection and conditional logistic regression analysis, an overall 9% increase in odds of hospitalization for acute renal failure per 5°F (2.78°C) was found for mean temperature at a one day lag …


Ecological Literacy, Nutrition Knowledge, And Dietary Practices Among Students At University At Albany, Elaine Hills Jan 2012

Ecological Literacy, Nutrition Knowledge, And Dietary Practices Among Students At University At Albany, Elaine Hills

Legacy Theses & Dissertations (2009 - 2024)

University students (N=1,924) at a large public university were surveyed to measure their nutrition knowledge, dietary practices, and ecological literacy. A quantitative measure of ecological literacy was developed for this purpose, reflecting familiarity with nature, awareness of one's personal impact on local and global ecologies, and personal lifestyle choices that demonstrate civic responsibility for the natural environment. The association between nutrition knowledge and dietary practices was compared to the association between ecological literacy and dietary practices. The results showed that: (1) many students were not familiar with public health eating recommendations and did not eat recommended amounts of foods, particularly …


Association Between Chemical Constituents Of Particulate Matter And Cardiovascular And Respiratory Morbidities In Nys, Rena Jones Jan 2012

Association Between Chemical Constituents Of Particulate Matter And Cardiovascular And Respiratory Morbidities In Nys, Rena Jones

Legacy Theses & Dissertations (2009 - 2024)

Improved understanding of health risks from short- and long-term exposure to fine particulate matter (PM2.5) constituents may explain seasonal and geographic heterogeneity in PM2.5-health associations and inform control efforts targeting PM sources. Few studies have examined PM species health effects; most have been limited by their exposure assessments and modeling approaches. The goals of this project were to improve the PM exposure assessment and explore relationships between PM2.5 species and health in acute and chronic contexts.


Short-Term Associations Between Pm2.5, Black Carbon, Delta-C, And Cardiovascular Diseases In A Large Developing Megacity, Daniel Malashock Jan 2012

Short-Term Associations Between Pm2.5, Black Carbon, Delta-C, And Cardiovascular Diseases In A Large Developing Megacity, Daniel Malashock

Legacy Theses & Dissertations (2009 - 2024)

Introduction: Association between ambient air pollution and cardiovascular disease (CVD) have been demonstrated by many epidemiological studies in developed countries, however few studies have been performed in developing countries of Asia.