The impact of collective efficacy beliefs on effort and persistence in a group task

Collective efficacy is an important determinant of the motivation of individuals within groups, with increases in collective efficacy producing more effort in a task and greater persistence when faced with failure. To test hypotheses concerning the impact of collective efficacy on effort and persistence, participants (n = 22) were assigned to triads (consisting of the participant and two confederates) and performed three time trials on cycle ergometers. After trial 1, the participants were assigned to either a high or low collective efficacy condition, receiving appropriate bogus performance feedback. All groups received failure feedback after trial 2. Effort was assessed by performance time and maximum heart rate (HRmax) achieved during performance. A 2 (collective efficacy condition) x 3 (trials) analysis of variance with repeated measures on trials revealed significant interaction effects for both performance time and HRmax. Fisher's least significant difference post-hoc tests indicated that, following efficacy manipulation, groups low in collective efficacy significantly reduced both their performance time and HRmax, whereas groups high in collective efficacy maintained performance and HRmax. However, predictions concerning the impact of failure on persistence were not supported. Our results provide partial support for the role of collective efficacy in team sports.     

Differences in activation patterns between eccentric and concentric quadriceps contractions.

Previous studies analysing electromyograms (EMGs) from indwelling electrodes have indicated that fast-twitch motor units are selectively recruited for low-intensity eccentric contractions. The aim of this study was to compare the frequency content of surface EMGs from quadriceps muscles during eccentric and concentric contractions at various contraction intensities. Electromyograms were recorded from the rectus femoris, vastus lateralis and vastus medialis muscles of 10 men during isokinetic (1.05 rad x s(-1)) eccentric and concentric knee extension contractions at 25%, 50%, 75% and 100% of maximal voluntary contraction (MVC) for each contraction mode. Additionally, isometric contractions (70 degrees) were performed at each intensity. The mean frequency and root mean square (RMS) of the surface EMG were computed. Mean frequency was higher for eccentric than concentric contractions at 25% (P < 0.01), 50% (P < 0.01) and 75% (P < 0.05) but not at 100% MVC. It increased with increasing contraction intensity for isometric (P < 0.001) and concentric (P < 0.01) contractions but not for eccentric contractions (P = 0.27). The EMG amplitude (RMS) increased with increasing contraction intensity similarly in each contraction mode (P < 0.0001). Higher mean frequencies for eccentric than concentric contractions at submaximal contraction intensities is consistent with more fast-twitch motor units being active during eccentric contractions.     

IAIMS and the library at the University of Utah

The formal creation of an Integrated Academic Information Management System (IAIMS) at the University of Utah began in the fall of 1983. The keystone of the IAIMS effort is the HELP hospital information system. IAIMS at the University of Utah is a broad-based program extending across the Health Sciences Center and beyond to health professionals throughout the inter-mountain area. This paper describes the background that led to IAIMS, the IAIMS planning process, and the library's participation in this effort.     

Bibliographic control of medical illustrations--a case study in the development of a library subsystem: I. Project planning

The need to provide bibliographic access to a collection of original medical illustrations led the Library of the University of California, San Francisco, to search for a bibliographic control system and, not finding a satisfactory one, to develop one of its own, Part 1 of the report details the planning for such a development, including the need for bibliographic control of illustrations, the goals of the proposed system, design decisions and changes required, the type of system chosen, special subjects indexing needs, the required output, and staffing and budgetary needs.     

SOCIOMETRIC STATUS SCORES: A COMPARISON OF JAMRICH VALUES WITH CONVENTIONAL SCALES

Sociometric ranking of ten classrooms was analyzed to determine if Jamrich's procedure was significantly different from conventional indexes. Spearman Rank correlations and Kendall's coefficient of concordance were used to determine degree of correlation, Jamrich's ranked values were not found to be significantly different from conventional scales.