Visualizing protein interactions and dynamics: evolving a visual language for molecular animation

Undergraduate biology education provides students with a number of learning challenges. Subject areas that are particularly difficult to understand include protein conformational change and stability, diffusion and random molecular motion, and molecular crowding. In this study, we examined the relative effectiveness of three-dimensional visualization techniques for learning about protein conformation and molecular motion in association with a ligand-receptor binding event. Increasingly complex versions of the same binding event were depicted in each of four animated treatments. Students (n = 131) were recruited from the undergraduate biology program at University of Toronto, Mississauga. Visualization media were developed in the Center for Molecular and Cellular Dynamics at Harvard Medical School. Stem cell factor ligand and cKit receptor tyrosine kinase were used as a classical example of a ligand-induced receptor dimerization and activation event. Each group completed a pretest, viewed one of four variants of the animation, and completed a posttest and, at 2 wk following the assessment, a delayed posttest. Overall, the most complex animation was the most effective at fostering students' understanding of the events depicted. These results suggest that, in select learning contexts, increasingly complex representations may be more desirable for conveying the dynamic nature of cell binding events.     

An instrument in search of a theory: Structural validity of the Kaufman assessment battery for children-second edition normative update at school-age

The present study examined the factor structure of the Kaufman assessment battery for children-second edition normative update with normative sample participants aged 7–18 years (N = 500) using confirmatory factor analysis with maximum likelihood estimation and multidimensional scaling procedures. For the 10 subtest Cattell-Horn-Carroll core battery configuration, an alternative hierarchical model with four group-specific factors (crystallized ability, perceptual reasoning, short-term memory, and long-term storage and retrieval) provided the best fit to the normative data for both age groups. These results suggest caution for interpreting the visual processing and fluid reasoning index scores in isolation given the inability to locate those constructs independently at school-age. Implications for the clinical interpretation of the measurement instrument moving forward are discussed.     

Muscle activity and spine load during anterior chain whole body linkage exercises: the body saw,hanging leg raise and walkout from a push-up

This study examined anterior chain whole body linkage exercises, namely the body saw, hanging leg raise and walkout from a push-up. Investigation of these exercises focused on which particular muscles were challenged and the magnitude of the resulting spine load. Fourteen males performed the exercises while muscle activity, external force and 3D body segment motion were recorded. A sophisticated and anatomically detailed 3D model used muscle activity and body segment kinematics to estimate muscle force, and thus sensitivity to each individual's choice of motor control for each task. Gradations of muscle activity and spine load characteristics were observed across tasks. On average, the hanging straight leg raise created approximately 3000 N of spine compression while the body saw created less than 2500 N. The hanging straight leg raise created the highest challenge to the abdominal wall (>130% MVC in rectus abdominis, 88% MVC in external oblique). The body saw resulted in almost 140% MVC activation of the serratus anterior. All other exercises produced substantial abdominal challenge, although the body saw did so in the most spine conserving way. These findings, along with consideration of an individual's injury history, training goals and current fitness level, should assist in exercise choice and programme design.     

ASSESSING THE INCREMENTAL VALUE OF KABC‐II LURIA MODEL SCORES IN PREDICTING ACHIEVEMENT: WHAT DO THEY TELL US BEYOND THE MPI?

The current study examined the incremental validity of the Luria interpretive scheme for the Kaufman Assessment Battery for Children‐Second Edition (KABC‐II) for predicting scores on the Kaufman Test of Educational Achievement‐Second Edition (KTEA‐II). All participants were children and adolescents (N = 2,025) drawn from the nationally representative KABC‐II/KTEA‐II linked standardization sample. Consistent with previous studies, the full scale Mental Processing Index (MPI) score accounted for clinically significant portions of KTEA‐II score variance in all of the regression models that were assessed. In contrast, the Luria factor scores collectively failed to provide meaningful incremental predictive variance after controlling for the effects of the MPI. Individually, the factor scores consistently accounted for trivial portions of achievement variance. Potential implications of these results for the correct interpretation of the KABC‐II within clinical practice are discussed.     

The Costs of Experience Corps® in Public Schools

Objective: To describe the annual operational costs of a mature Experience Corps® program in elementary schools in the Baltimore City Public School System. Methods: Systematic records of expenditures kept by the community partner, Greater Homewood Community Corporation, to be reported to funders were made available for analysis. Expenditures were aggregated to the level of fiscal year and grouped in categories in consultation with the community partner. Results: Expenditures to provide reimbursement to volunteers and to administer this complex volunteer program in an environment in which the school district needed additional management resources for such a program dominate the total expenditures. In the 2008 fiscal year, the program provided 158,305 hours of older adult volunteer service to public elementary schools in Baltimore City and the cost per volunteer hour was $9.79; in the 2009 fiscal year the program provided 157,238 hours of older adult volunteer service and the cost per volunteer hour was $9.60. This suggests consistency and may also suggest that the program is becoming more efficient over time. Conclusion: The costs presented represent the costs of running a mature program after an initial investment has been made. These costs would need to be compared with the short-term and long-term benefits to the older adult volunteers, the school children, other school personnel, and the schools' and volunteers' communities to perform a comprehensive benefit-cost analysis to inform public policy.     

Investigating the theoretical structure of the DAS‐II core battery at school age using Bayesian structural equation modeling

Bayesian structural equation modeling (BSEM) was used to investigate the latent structure of the Differential Ability Scales—Second Edition core battery using the standardization sample normative data for ages 7–17. Results revealed plausibility of a three‐factor model, consistent with publisher theory, expressed as either a higher‐order (HO) or a bifactor (BF) model. The results also revealed an alternative structure with the best model fit, a two‐factor BF model with Matrices (MA) and Sequential and Quantitative Reasoning (SQ) loading on g only with no respective group factor loading. This was only the second study to use BSEM to investigate the structure of a commercial ability test and the first to use a large normative sample and the specification of both approximate zero cross‐loadings and correlated residual terms. It is believed that the results produced from the current study will advance the field's understanding of not only the factor structure of the DAS‐II core battery but also the potential utility of BSEM in psychometric investigations of intelligence test structures.     

Field Study and the Rhetoric Curriculum

Using field study to teach writing and speaking in rhetoric impacts both how technical communication defines itself and its role in the curriculum. This article reviews materials that support field study, describes course assignments, and examines student writing. I find that as field study offers a precise, event-based resource for teaching rhetoric, so rhetoric offers an audience-centered format to bring properties of the field inside.     

Studying computer programming externally: Who succeeds?

Learning computer programming is difficult for many students. Distance education students in particular often have problems as the difficulty of the course content is compounded by the problems of isolation from other students and their tutor. This paper reports an investigation of distance education student performance in an introductory computer programming course. The aim of the study was to develop a better understanding of the factors associated with academic success, withdrawal or failure and to attempt to identify students at risk of non‐completion. Some implications for teaching computer programming externally are discussed.     

Addressing Disparities in Parent Education: Examining the Effects of Learn the Signs/Act Early Parent Education Materials on Parent Outcomes

Early intervention is critical for improved prognosis and quality of life for young children with developmental delays and disabilities. Yet, disparities persist among underserved families with young children. These disparities include knowledge of child development, use of medical providers as referral sources, and later diagnosis. The current study employed a mixed method, randomized controlled trial to examine participant outcomes among low-income, underserved families who received child development information. The information included the 42-page Milestone Moments booklet that was developed by the Centers for Disease Control and Prevention’s Learn the Signs/Act Early initiative. Participants (n = 108) included parents or legal guardians of children ages birth through 5 years. The participants were predominantly Black/African American (86 %) and female (90 %), and all had incomes below the federal poverty level. Study variables related to the location (home vs. child care center) and context (single session vs. extended visits) for delivering the information did not yield significant differences. Yet, there were clear findings that parents who received the booklet reported increased knowledge about child development, a decrease in concern about their own children’s developmental progress, and a positive perception of the booklet. On interview, parents reported learning new information about child development or being reminded of developmental information they had forgotten and the importance of following up with professionals when concerns arose. While not statistically significant, there was a consistent trend toward greater participant outcomes for parents who received materials in the child care setting relative to the home.