What next? Three knowledge objectives for communication researchers

This essay identifies as knowledge objectives the need to (1) understand the interrelatedness of communicative contexts, (2) pinpoint more precisely the serial nature of communication, and (3) establish the relationship between laboratory and naturalist investigations     

Studies on the use of fear appeals: A summary and analysis

While a number of studies have been concerned with the effects of varying intensities of fear appeals on audience response, interpretation of the findings poses a number of problems. The author summarizes some of the major research thus far conducted, analyzes several of the problems involved in interpreting the findings of these studies, and provides some tentative suggestions for fruitful approaches to the study of the effects of fear‐arousing appeals.     

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.     

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.