213 research outputs found

    Statistical Modeling and Optimization of Nuclear Waste Vitrification

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    This thesis describes the development of a methodology to minimize the cost of vitrifying nuclear waste. Pacific Northwest Laboratory (PNL) regression models are used as baseline equations for modeling glass properties such as viscosity, electrical conductivity, and two types of durability. Revised PNL regression models are developed that eliminate insignificant variables from the original models. The Revised PNL regression model for electrical conductivity is shown to better predict electrical conductivity than the original PNL regression model. Neural networks are developed for viscosity and the two types of durability, PCT-B and MCC-1 B. The neural network models are shown to outperform every PNL and Revised PNL regression model in terms of predicting property values for viscosity, PCT-B, and MCC-1 B. The combined Neural Network/Revised PNL 2nd order electrical conductivity models are shown to be the best classifiers of nuclear waste glass, i.e. they have the highest probability of classifying a vitrified waste form as glass when it actually did produce glass in the laboratory. Finally, five nonlinear programs are developed with constraints containing: (1) the PNL original 1st order models, (2) the PNL original 2nd order models, (3) the Revised PNL 1st order models, (4) the Revised PNL 2nd order models, and (5) the Neural Network/Revised PNL 2nd order electrical conductivity models. The Neural Network/Revised PNL 2nd order electrical conductivity nonlinear program is shown to minimize the total expected cost of vitrifying nuclear waste glass. This nonlinear program allows DOE to minimize its risk and cost of high-level nuclear waste vitrification

    A Combined Adaptive Tabu Search and Set Partitioning Approach for the Crew Scheduling Problem with an Air Tanker Crew Application

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    This research develops the first metaheuristic approach to the complete air crew scheduling problem. It develops the first dynamic, integrated, set-partitioning based vocabulary scheme for metaheuristic search. Since no benchmark flight schedules exist for the tanker crew scheduling problem, this research defines and develops a Javaℱ based flight schedule generator. The robustness of the tabu search algorithms is judged by testing them using designed experiments. An integer program is developed to calculate lower bounds for the tanker crew scheduling problem objectives and to measure the overall quality of solutions produced by the developed algorithms

    Developing an evidence-based program sustainability training curriculum: A group randomized, multi-phase approach

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    Abstract Background The emergence of dissemination and implementation (D&I) science has driven a rapid increase in studies of how new scientific discoveries are translated and developed into evidence-based programs and policies. However, D&I science has paid much less attention to what happens to programs once they have been implemented. Public health programs can only deliver benefits if they reach maturity and sustain activities over time. In order to achieve the full benefits of significant investment in public health research and program development, there must be an understanding of the factors that relate to sustainability to inform development of tools and trainings to support strategic long-term program sustainability. Tobacco control programs, specifically, vary in their abilities to support and sustain themselves over time. As of 2018, most states still do not meet the CDC-recommended level for funding their TC program, allowing tobacco use to remain the leading cause of preventable disease and death in the USA. The purpose of this study is to empirically develop, test, and disseminate training programs to improve the sustainability of evidence-based state tobacco control programs and thus, tobacco-related health outcomes. Methods This paper describes the methods of a group randomized, multi-phase study that evaluates the empirically developed “Program Sustainability Action Planning Training” and technical assistance in US state-level tobacco control programs. Phase 1 includes developing the sustainability action planning training curriculum and technical assistance protocol and developing measures to assess long-term program sustainability. Phase 2 includes a group randomized trial to test the effectiveness of the training and technical assistance in improving sustainability outcomes in 24 state tobacco control programs (12 intervention, 12 comparison). Phase 3 includes the active dissemination of final training curricula materials to a broader public health audience. Discussion Empirical evidence has established that program sustainability can improve through training and technical assistance; however, to our knowledge, no evidence-based sustainability training curriculum program exists. Therefore, systematic methods are needed to develop, test, and disseminate a training that improves the sustainability of evidence-based programs. Trial registration NCT03598114. Registered 25 July 2018—retrospectively registered

    Public health information seeking, trust, and COVID-19 prevention behaviors: Cross-sectional study

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    BACKGROUND: Preventative health measures such as shelter in place and mask wearing have been widely encouraged to curb the spread of the COVID-19 disease. People\u27s attitudes toward preventative behaviors may be dependent on their sources of information and trust in the information. OBJECTIVE: The aim of this study was to understand the relationship between trusting in COVID-19 information and preventative behaviors in a racially and politically diverse metropolitan area in the United States. METHODS: We conducted a web-based cross-sectional survey of residents in St. Louis City and County in Missouri. Individuals aged ≄18 years were eligible to participate. Participants were recruited using a convenience sampling approach through social media and email. The Health Belief Model and the Socioecological Model informed instrument development, as well as COVID-19-related questions from the Centers for Disease Control and Prevention. We performed an ordinary least squares linear regression model to estimate social distancing practices, perceptions, and trust in COVID-19 information sources. RESULTS: Of the 1650 eligible participants, the majority (n=1381, 83.7%) had sought or received COVID-19-related information from a public health agency, the Centers for Disease Control and Prevention, or both. Regression analysis showed a 1% increase in preventative behaviors for every 12% increase in trust in governmental health agencies. At their lowest levels of trust, women were 68% more likely to engage in preventative behaviors than men. Overall, those aged 18-45 years without vulnerable medical conditions were the least likely to engage in preventative behaviors. CONCLUSIONS: Trust in COVID-19 information increases an individual\u27s likelihood of practicing preventative behaviors. Effective health communication strategies should be used to effectively disseminate health information during disease outbreaks

    Standardized Tobacco Assessment for Retail Settings (STARS): dissemination and implementation research

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    The Standardized Tobacco Assessment for Retail Settings (STARS) was designed to characterise the availability, placement, promotion and price of tobacco products, with items chosen for relevance to regulating the retail tobacco environment. This study describes the process to develop the STARS instrument and protocol employed by a collaboration of US government agencies, US state tobacco control programmes (TCPs), advocacy organisations, public health attorneys and researchers from the National Cancer Institute's State and Community Tobacco Control (SCTC) Research Initiative

    Asessing Retail Environments with STARS Standardized Tobacco Assessment for Retail Settings

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    This case study from the ASPiRE project highlights experiences in Indiana, Oregon, Texas, and Vermont, where partners used the Standardized Tobacco Assessment for Retail Settings (STARS) to better understand characteristics of the retail environment in local communities. STARS was designed as a user-friendly and concise tool to facilitate data collection for evidence-based tobacco control policies.https://openscholarship.wustl.edu/cphss/1108/thumbnail.jp

    Tobacco retail policy landscape: a longitudinal survey of US states

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    There are ∌380 000 tobacco retailers in the USA, where the largest tobacco companies spend almost $9 billion a year to promote their products. No systematic survey has been conducted of state-level activities to regulate the retail environment, thus little is known about what policies are being planned, proposed or implemented

    Tobacco Town: Computational Modeling of Policy Options to Reduce Tobacco Retailer Density

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    To identify the behavioral mechanisms and effects of tobacco control policies designed to reduce tobacco retailer density

    Who Is Most Vulnerable to Social Rejection? The Toxic Combination of Low Self-Esteem and Lack of Negative Emotion Differentiation on Neural Responses to Rejection

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    People have a fundamental need to belong that, when satisfied, is associated with mental and physical well-being. The current investigation examined what happens when the need to belong is thwarted—and how individual differences in self-esteem and emotion differentiation modulate neural responses to social rejection. We hypothesized that low self-esteem would predict heightened activation in distress-related neural responses during a social rejection manipulation, but that this relationship would be moderated by negative emotion differentiation—defined as adeptness at using discrete negative emotion categories to capture one\u27s felt experience. Combining daily diary and neuroimaging methodologies, the current study showed that low self-esteem and low negative emotion differentiation represented a toxic combination that was associated with stronger activation during social rejection (versus social inclusion) in the dorsal anterior cingulate cortex and anterior insula—two regions previously shown to index social distress. In contrast, individuals with greater negative emotion differentiation did not show stronger activation in these regions, regardless of their level of self-esteem; fitting with prior evidence that negative emotion differentiation confers equanimity in emotionally upsetting situations
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