Leveraging the Public School System to Combat Adolescent Obesity: The Limits of Arkansas’s Statewide Policy Initiative

Purpose: This study assessed the effectiveness of one of the earliest statewide policy initiatives to address obesity via schools—Arkansas’s Act 1220 of 2003—on adolescent obesity. The Act required public schools in Arkansas to conduct body mass index (BMI) screening and reporting, restrict access to vending machines and establish physical education and nutrition standards.Methods: To determine the effect of Act 1220 as a whole, this study analyzed data representative of adolescents in grades 9-12 from the Youth Risk Behavior Survey (YRBS) using the quasi-experimental method of difference-in-differences. Changes in adolescents’ weight outcomes in Arkansas before (1999 and 2001) and after (2005, 2007 and 2009) the implementation of Act 1220 were compared to changes in weight outcomes for adolescents from the neighboring state of Missouri across the same time period.Results: Arkansas’s Act 1220 did not significantly influence adolescents’ BMI-for-age z-scores (zBMI) (-0.017; 95% confidence interval [CI] [-0.097, 0.063]; p=.68). Further, the Act did not lead to significant reductions in zBMI among adolescents who were either overweight (-0.003; 95% CI [-0.043, 0.036]; p=.86) or obese (-0.010; 95% CI [-0.070, 0.051]; p=.75). Results remain robust to adjustments for self-report bias in height and weight as well as a set of alternative comparison states.Conclusions: Preventing adolescent overweight and obesity is unlikely to occur through such large-scale policy initiatives alone

Effect of reduced computer precision on a midcourse navigation and guidance system using optimal filtering and linear prediction

Reduced computer precision effect on midcourse navigation and guidance system using optimal filtering and linear predictio

Evaluation of an anthropomorphic user interface in a travel reservation context and affordances

This paper describes an experiment and its results concerning research that has been going on for a number ofyears in the area of anthropomorphic user interface feedback. The main aims of the research have been to examine theeffectiveness and user satisfaction of anthropomorphic feedback in various domains. The results are of use to all interactivesystems designers, particularly when dealing with issues of user interface feedback design. There is currently somedisagreement amongst computer scientists concerning the suitability of such types of feedback. This research is working toresolve this disagreement. The experiment detailed, concerns the specific software domain of Online Factual Delivery in thespecific context of online hotel bookings. Anthropomorphic feedback was compared against an equivalent non-anthropomorphicfeedback. Statistically significant results were obtained suggesting that the non-anthropomorphic feedback was more effective.The results for user satisfaction were however less clear. The results obtained are compared with previous research. Thissuggests that the observed results could be due to the issue of differing domains yielding different results. However the resultsmay also be due to the affordances at the interface being more facilitated in the non-anthropomorphic feedback

Distress thermometer (SUDS). modified for use in participatory arts evaluations

Subjective Units of Distress Scale was designed in 1969 by Wolpe. It is frequently used in CBT treatments concerning distress and for research purposes. We have re-designed this scale with just three anchor points on the thermometer, encouraging subjective self-rating. The scale is designed to look non-medical, and to encourage engagement in arts and health settings through simple, sophisticated design and clear instructions which refrain from medical instructions and labelling

Modeling and simulation of a Stewart platform type parallel structure robot

The kinematics and dynamics of a Stewart Platform type parallel structure robot (NASA's Dynamic Docking Test System) were modeled using the method of kinematic influence coefficients (KIC) and isomorphic transformations of system dependence from one set of generalized coordinates to another. By specifying the end-effector (platform) time trajectory, the required generalized input forces which would theoretically yield the desired motion were determined. It was found that the relationship between the platform motion and the actuators motion was nonlinear. In addition, the contribution to the total generalized forces, required at the actuators, from the acceleration related terms were found to be more significant than the velocity related terms. Hence, the curve representing the total required actuator force generally resembled the curve for the acceleration related force. Another observation revealed that the acceleration related effective inertia matrix I sub dd had the tendency to decouple, with the elements on the main diagonal of I sub dd being larger than the off-diagonal elements, while the velocity related inertia power array P sub ddd did not show such tendency. This tendency results in the acceleration related force curve of a given actuator resembling the acceleration profile of that particular actuator. Furthermore, it was indicated that the effective inertia matrix for the legs is more decoupled than that for the platform. These observations provide essential information for further research to develop an effective control strategy for real-time control of the Dynamic Docking Test System

Singular values of some modular functions

We study the properties of special values of the modular functions obtained from Weierstrass P-function at imaginary quadratic points.Comment: 19 pages,corrected typo