One-arm maximal strength training improves work economy and endurance capacity but not skeletal muscle blood flow

Maximal strength training with a focus on maximal mobilization of force in the concentric phase improves endurance performance that employs a large muscle mass. However, this has not been studied during work with a small muscle mass, which does not challenge convective oxygen supply. We therefore randomized 23 adult females with no arm-training history to either one-arm maximal strength training or a control group. The training group performed five sets of five repetitions of dynamic arm curls against a near-maximal load, 3 days a week for 8 weeks. This training increased maximal strength by 75% and improved rate of force development during both strength and endurance exercise, suggesting that each arm curl became more efficient. This coincided with a 17-18% reduction in oxygen cost at standardized submaximal workloads (work economy), and a 21% higher peak oxygen uptake and 30% higher peak load during maximal arm endurance exercise. Blood flow assessed by Doppler ultrasound in the axillary artery supplying the working biceps brachii and brachialis muscles could not explain the training-induced adaptations. These data suggest that maximal strength training improved work economy and endurance performance in the skeletal muscle, and that these effects are independent of convective oxygen supply.     

The Semiotic Function of a Bridging Representation to Support Students’ Meaning-Making in Solution Chemistry

Research in Science Education - Many researchers have reported that bridging analogies can productively support students’ scientific meaning-making. How this can be understood semiotically...     

A Window for a Purpose: Developing a Framework for Describing Effective Science Teaching and Learning

This paper describes the development of a framework – the SIS Components – for describing effective teaching and learning in science, to support a system wide change initiative. The methodology used and the analysis that led to their refinement, is traced to expose the different issues involved in constructing the notion of effective practice. These issues have to do with purpose, politics and audience. They determine features of the framework such as specificity, elements focused on, and the support structures that are put in place to establish the particular discourse being promoted. The paper describes the different research methods used to establish, to promote and to validate the components, and outlines the different senses in which this and any framework can be seen as contingent on the setting for which it is intended.     

Mass Communications

“Popular Culture in America” edited by David Manning White with help from Ray Browne, Marshall Fishwick, and Russel B. Nye

Marshall Fishwick, is author of his latest, a collection of his own essays entitled Parameters of Popular Culture (Bowling Green, Ohio: Bowling Green University Popular Press, 1974—cost not known, but available in cloth and paper)

J. Meredith Neil to assemble Popular Architecture (Bowling Green, Ohio: Bowling Green Popular Press, n.d., but , 1974—price not given, paper)

James Philip Danky's UndergroundS; A Union List of Alternative Periodicals in Libraries of the United States and Canada (Madison: State Historical Society of'Wisconsin, 1974—$12.95, paper)

George D. Brightbill and Wayne C. Maxon's Citation Manual for United States Government Publications (Philadelphia: Temple University's Center for the Study of Federalism, 1974—75¢, paper)     

General Works on Mass Communications

Russel B. Nye's The Unembarrassed Muse: The Popular Arts in America (Dial Press, $12.50)

Otto Friedrich's Decline and Fall (Harpor & Row, $10.00)

“The Sociology of Mass Media Communicators,” The Sociological Review Monograph No. 13 (University of Keele, Staffordshire, England, January 1969, $4.60 including air mail costs)

Audio Visual Marketplace: A Multimedia Guide (Bowker, $12.25)

Jerry Della Femina's From Those Wonderful Folks Who Gave You Pearl Harbor (Simon and Schuster, $6.50)     

Influence of measurement errors on HIV risk behavior analysis: A case study examining condom use among drug users

Multiple indicators of HIV risk behaviors are not yet well developed in the field of drug abuse and AIDS prevention, with most research relying on single‐item measures. Weak or inconclusive statistical analyses often result from measurement errors. This study illustrates the problems of biased statistical estimates when single‐item measures with measurement errors are used. Using HIV risk behaviors among injection drug users as an example, this study shows the impact of measurement error on statistical results in path analysis. The results suggest that more attention is needed to address the issue of measurement reliability in survey data. Measurement error should be taken into account in analyzing HIV risk behaviors, and appropriate multiple indicators for a full range of HIV risk behaviors should be developed to deal successfully with the “errors‐in‐variables” problem.