Effects of Attention Allocation on Habituation to Food Cues in Normal Weight and Overweight Children

ABSTRACT OF THE DISSERTATION Effects of Attention Allocation on Habituation to Food Cues in Normal weight and Overweight Children by Vandana Passi Aspen Doctor of Philosophy in Psychology Washington University in St. Louis, 2010 Professor Denise Wilfley, Chairperson Despite the rising prevalence of pediatric overweight, minimal research has been conducted to understand the basic biological processes underlying overweight in children. The present study assesses changes in physiological response: i.e., salivation) to food over time. The primary aims were to examine whether salivation patterns in children vary based on weight status and/or allocating attention to a distracter task. It was hypothesized that: 1) overweight children would not habituate: salivation at the final trial would not decrease back to baseline level), regardless of distracter task condition while the normal weight children would habituate: i.e., salivation at the final trial would decrease back to baseline level) and that 2) all children attending to the distracter task would take longer to habituate as compared to those not attending to the task. Participants were 31 normal weight and 26 overweight children ages 9 to12 years. All children were presented with nine one-minute trials of a food stimulus: French fries). During each intertrial interval, participants either listened to sequential one-minute presentations of an audio-book: distracter task) or listened to white noise: no-distracter-task control). Pattern and rate of salivation were measured using a validated procedure: the Strongin-Hinsie Peck method) and analyzed using repeated measures ANCOVA and Kaplan-Meier survival analysis. The rate of change in salivation over trials differed significantly by weight status: p = .01) but not by distracter task condition: p \u3e .10). Specifically, regardless of distracter task condition, at the final trial of the study, normal weight children habituated to food cues while overweight children did not. Results suggest that children\u27s physiological response to food is related to weight status. Such atypical habituation patterns could potentially lead to overconsumption, thus serving as a possible causal or maintaining factor in childhood overweight. The lack of a distracter effect is in contrast to previous findings and may be due to differences in methodology across studies. Future directions, including, a) experiments to explore causal mechanisms, b) experiments testing habituation in more naturalistic settings and, c) prospective studies to determine the role of salivary response in OW, are discussed

Essays on the Economics of Electric Vehicle Charging Stations

Electric vehicles (EVs) have peaked people’s interest since the first electric-powered vehicle was developed in the 1830’s. By the 1890’s EVs were the most common vehicle in the U.S. However, due to issues with charging batteries and limitations of the electrical grid, EVs were left behind as gasoline vehicles became commonly available in the early 20th century. Several attempts to repopularize EVs over the last 100 years suffered from difficulties with limited driving ranges, but today, expanded driving ranges and improved charging capabilities have made EVs a real alternative to gasoline engines. The possibility of zero-emission transportation made possible by EVs has fueled both public and private investment in EV charging infrastructure through a variety of subsidies. However, a better understanding of how charging stations are utilized and of the effects of charging station subsidies on drivers and station development is essential. This dissertation studies how charging station subsidies, station location, and prices affect driver charging behavior and new station construction

Identifying significant factors and optimal sites for commercial salmon farming in northern Norway. An integrated GIS and machine learning approach using random forest.

This study presents a data-driven modelling approach to identify important factors influencing the growth- and mortality rate for farmed salmon in northern Norway. Furthermore, a model is trained to determine the best fish farming sites and identify optimal areas with the best geographical conditions. Aquaculture site production and location data from 323 salmon farming sites (all licensed aquaculture sites) in northern Norway were obtained from the Directory of Fisheries. Two dependent variables, growth- and mortality rate, were calculated based on the monthly increase in biomass and mortality. These variables were combined with state-of-the-art environmental- and exploratory socio-economic data obtained from the institute of marine research (IMR), the Norwegian Meteorological Institute, Delft University of Technology, Norwegian Coastal Administration, and Statistics Norway. Using random forest regression and recursive feature elimination, a data-driven ensemble approach identified significant variables. Prediction of optimal sites for salmon farming in northern Norway was done with a species distribution modelling approach using random forest classification. The important factors affecting salmon growth were specific feeding rate, temperature, and total biomass. The important factors influencing salmon mortality were temperature and total biomass. The predicted optimal areas were inside Vefsnfjorden, Ranfjorden, Sørfjorden and Glomfjorden, small areas near the coast and around the small islands stretching from Gladstad to Narvik. Areas near the coast of Lofoten, Værøy, Røst, Vesterålen, Sortland and Senja. Further north, some dispersed regions were predicted as optimal outside Tromsø and Sørøya. Also large areas around Varangerhalvøya, Olderdalen/Kåfjorden, Lille Altafjorden and near the shore on both sides of Stjernøysundet. The results clearly show that space is a scares resource and that there is an urge to evaluate the regulations and legislations concerning aquaculture in Norway. Especially the minimum distances between the fairways and aquaculture locations. The incorporation of machine learning approaches in GIS-based MCE analysis is suggested to help planners and decision-makers make informed and sustainable decisions about sea-area use

Intergenerational Teenage Motherhood: Memory and Material Culture

This paper explores how memories and material culture can be used to understand intergenerational teenage motherhood. Intimate, feminist ethnography is used to explore the experiences of my mother and my grandmother who were both teenage mothers. Teenage mothers are blamed for perpetuating a cycle of poverty in the United States by conservative and neoliberal adherents, yet women were young mothers throughout the history of the United States. In their minds, teenage mothers have daughters who become teenage mothers themselves, which then maintains poverty across generations. This project counters that false narrative by focusing on the experiences of intergenerational teenage mothers through the stories they tell related to belongings from their time as young mothers. I argue we need to focus on teenage mother’s needs instead of viewing their circumstances as a ‘problem’ that needs solved