Food Fury: Online Casual Game Development for Nutrition Education

Introduction: The United States is currently experiencing increased prevalence of obesity. This is a particular problem amongst children who require dietary and activity behavioral change to mitigate this problem. The use of computer games as channels to motivate health behavior in children is increasing. Casual games are a subset of computer games that are simple in design, easy to access and play, popular with children, and have the potential to be effective for drill and practice learning. [See PDF for complete abstract]

Making minimally invasive THR safe: conclusions from biomechanical simulation and analysis.

The use of smaller surgical incisions has become popularized for total hip arthroplasty (THR) because of the potential benefits of shorter recovery and improved cosmetic appearance. However, an increased incidence of serious complications has been reported. To minimize the risks of minimally invasive approaches to THR, we have developed an experimental approach which enables us to evaluate risk factors in these procedures through cadaveric simulations performed within the laboratory. During cadaveric hip replacement procedures performed via posterior and antero-lateral mini-incisions, pressures developed between the wound edges and the retractors were approximately double those recorded during conventional hip replacement using Charnley retractors (p < 0.01). In MIS procedures performed via the dual-incision approach, lack of direct visualisation of the proximal femur led to misalignment of broaches and implants with increased risk of cortical fracture during canal preparation and implant insertion. Cadaveric simulation of surgical procedures allows surgeons to measure variables affecting the technical success of surgery and to master new procedures without placing patients at risk.

THEORETICAL STUDIES ON THE METHODS OF RECONSTRUCTING PHYLOGENETIC TREES FROM DNA SEQUENCE DATA (MOLECULAR EVOLUTION, HOMINOID EVOLUTION, COMPUTER SIMULATION)

(1) A mathematical theory for computing the probabilities of various nucleotide configurations is developed, and the probability of obtaining the correct phylogenetic tree (model tree) from sequence data is evaluated for six phylogenetic tree-making methods (UPGMA, distance Wagner method, transformed distance method, Fitch-Margoliash's method, maximum parsimony method, and compatibility method). The number of nucleotides (m*) necessary to obtain the correct tree with a probability of 95% is estimated with special reference to the human, chimpanzee, and gorilla divergence. m* is at least 4,200, but the availability of outgroup species greatly reduces m* for all methods except UPGMA. m* increases if transitions occur more frequently than transversions as in the case of mitochondrial DNA. (2) A new tree-making method called the neighbor-joining method is proposed. This method is applicable either for distance data or character state data. Computer simulation has shown that the neighbor-joining method is generally better than UPGMA, Farris' method, Li's method, and modified Farris method on recovering the true topology when distance data are used. A related method, the simultaneous partitioning method, is also discussed. (3) The maximum likelihood (ML) method for phylogeny reconstruction under the assumption of both constant and varying evolutionary rates is studied, and a new algorithm for obtaining the ML tree is presented. This method gives a tree similar to that obtained by UPGMA when constant evolutionary rate is assumed, whereas it gives a tree similar to that obtained by the maximum parsimony tree and the neighbor-joining method when varying evolutionary rate is assumed. ^

Assessing fun in serious games: Formative evaluation of games from two diabetes prevention interventions

Purpose. To determine the usability of two video games to prevent type 2 diabetes and obesity among youth through analysis of data collected during alpha-testing. ^ Subjects. Ten children aged 9 to 12 were selected for three 2-hour alpha testing sessions.^ Methods. "Escape from Diab" and "Nanoswarm" were designed to change dietary and physical inactivity behaviors, based on a theoretical framework of mediating variables obtained from social cognitive theory, self-determination theory, elaboration likelihood model, and behavioral inoculation theory. Thirteen mini-games developed by the software company were divided into 3 groups based on completion date. Children tested 4-5 mini-games in each of three sessions. Observed game play was followed by a scripted interview. Results from observation forms and interview transcripts were tabulated and coded to determine usability. Suggestions for game modifications were delivered to the software design firm, and a follow-up table reports rationale for inclusion or exclusion of such modifications.^ Results. Participants were 50% frequent video game players and 20% non game-players. Most (60%) were female. The mean grade (indicating likeability as a subset of usability) across all games given by children was significantly greater than a neutral grade of 80% (89%, p < 0.01), indicating a positive likeability score. The games on average also received positive ratings for fun, helpfulness of instructions and length compared to neutral values (midpoint on likert scales) (all p < 0.01). Observation notes indicated that participants paid attention to the instructions, did not appear to have much difficulty with the games, and were "not frustrated", "not bored", "very engaged", "not fidgety" and "very calm" (all p < 0.01). The primary issues noted in observations and interviews were unclear instructions and unclear purpose of some games. Player suggestions primarily involved ways to make on screen cues more visible or noticeable, instructions more clear, and games more elaborate or difficult.^ Conclusions. The present study highlights the importance of alpha testing video game components for usability prior to completion to enhance usability and likeability. Results indicate that creating clear instructions, making peripheral screen cues more eye-catching or noticeable, and vigorously stating the purpose of the game to improve understandability are important elements. However, future interventions will each present unique materials and user-interfaces and should therefore also be thoroughly alpha-tested. ^