Explaining the academic performance of community college students who transfer to a senior institution

The academic performance of 361 community college students was investigated after their transfer to a comprehensive university. The predictor variables included personal, environmental, demographic, and pretransfer academic measures. The criterion was grade point average (GPA) at the senior institution. Analyses included moderated linear regression and a branching algorithm which forms subgroups to best explain criterion scores (AID-3). The academic pattern and performance at the community college was found to be very important to the relevance of specific factors related to the curriculum selected at the senior institution.     

The effect of l-citrulline and watermelon juice supplementation on anaerobic and aerobic exercise performance

Citrulline has been proposed as an ergogenic aid, leading to an interest in watermelon given its high citrulline concentration. The aim of this study was to determine the effects of a single, pre-exercise dose of l-citrulline, watermelon juice, or a placebo on the total maximum number of repetitions completed over 5 sets, time to exhaustion, maximal oxygen consumption (VO₂max), anaerobic threshold, and flow-mediated vasodilation. A randomised double-blind within-participants study design was used to examine these effects among 22 participants (n = 11 males). Supplementation included either a 7.5% sucrose drink containing 6 g of l-citrulline, 710 mL of watermelon juice (~1.0 g citrulline), or a 7.5% sucrose placebo drink. Supplementation was administered 1 or 2 h before exercise testing to investigate a timing effect. There was no significant effect between the three supplements for the total number of repetitions, time to exhaustion, VO₂max, anaerobic threshold, or flow-mediated vasodilation. There was also no interaction observed relative to gender or supplement timing (P > 0.05). A single dose of l-citrulline or watermelon juice as a pre-exercise supplement appears to be ineffective in improving exercise performance; however, greater doses of l-citrulline have been shown to be safe and are currently left unexamined.     

Applying Tablet‐Based Performance Support Application for Technicians’ Training at the Israeli Air Force: A Case Study

Performance support systems are mechanisms enabling users) productivity while reducing training expenses as support is being delivered in real time, often eliminating the need for costly pre‐performance training. Mobile technologies have created new opportunities for improved performance support systems, especially for tasks performed outside the offi ce. This article describes the fi rst mobile learning and performance support initiative taken by the Israeli Air Force. The project included the development and eff ectiveness pilot study of a learning and performance support application delivered via tablet to helicopter engine technicians. The application provided support videos and illustrations of maintenance routines, thereby enabling learning and practicing at the same time. Pilot study results show high performance levels of application users compared to those applying traditional methods. Results also show that self‐effi cacy levels were not aff ected by the successful performance achieved when using the mobile performance support application. Plans to expand mobile support use are also described.     

Physiological Responses to Maximal Treadmill and Handweighted Exercise

Abstract

The purpose of this investigation was to compare the peak physiological responses among four protocols that employed different amounts of handweighted exercise in 16 males (aged 26.3 ± 4.1 years). The four protocols were (a) uphill treadmill running (UR; 3.36 m-s¹, 2.5% grade increase-3 min¹); (b) uphill treadmill walking while pumping 1.36kg handweights (HW) (UWHW; 1.79ms¹, 5.0% grade increase-3 min¹; (c) treadmill walking while pumping .91-kg HW (WHW; 1.79 m-s¹, 0% grade, .91kg HW increase-3 min¹); and (d) standing in place and pumping HW (SHW; arm work as described in WHW). It was hypothesized that the peak responses would be inversely proportional to the estimated muscle mass activated (i.e., UR = UWHW > WHW > SHW). Dependent variables included peak oxygen uptake (VO₂ peak), peak heart rate (HRpeak), peak ventilation (V_epeak), and peak respiratory exchange ratio (RERpeak). No differences were noted between UR and UWHW with respect to any of the dependent variables. All variables (except RERpeak) were greater (p < .01) in UR and UWHW than either WHW or SHW. RERpeak was greater (p < .01) in UR and UWHW than in WHW. VO₂peak and HRpeak were greater (p < .01) in WHW when compared to SHW. Mean VO₂peak was 97.5, 69.7, and 60% of UR for UWHW, WHW, and SHW, respectively. Therefore, walking and pumping handweights provides a maximal stimulus to the oxygen transport system.     

The discrete charm of the bourgeoisie: quantum and continuous perspectives on innovation and growth

This paper discusses the relative merits of discrete versus continuous perspectives on innovation, technical change, and economic growth. It discusses the innovation time series literature in some detail to extract the continuous and clustering properties of the historical record on innovation. It then proposes a mosaic/avalanche model based on percolation theory and self-organized criticality to address this question.