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981.
This paper examines the increases in prices for the last twenty years for the journals listed in the 1987 Brandon/Hill list and for the last twelve years for those on a list of medical and general periodicals published annually in Library Journal. This information is compared to the general U.S. inflation rate as measured by the Consumer Price Index. Despite the decline in the general rate of inflation, the buying power of libraries has continued to dwindle. Librarians need to use this information when justifying increased budget requests. They also need to interact more effectively with publishers to resolve this problem. The buying power of the dollar (as compared to the 1975 dollar) spent on the Brandon/Hill list journals is now 59% of that of a dollar spent in the general economy. This compares to 64% in 1983, when this research was last updated.  相似文献   
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The purpose of this study was to use generalizability theory with both univariate and multivariate approaches to examine reliability of total body center of mass (CM) values calculated from cinematographical data. Twenty-eight college-aged male volunteers were filmed by a LOCAM camera at 100 fps while performing the basic locomotion skill of walking. Film analysis was conducted on each subject using six frames of film depicting a one-stride walking cycle consisting of right heel strike, right foot flat, left toe-off, left heel strike, left foot flat, and right toe-off. Nineteen segmental endpoints and a reference point were digitized by three experienced plotters. The digitizing sequence was replicated three times by each plotter. A FORTRAN program calculated nine CM values (three plotters by three repetitions) for each subject filmed in each of the six positions of the stride. The x- and y-coordinates of the CM values were the dependent variables analyzed by fully crossed 3-way univariate and multivariate ANOVAs (subjects by plotters by repetitions). All measurement facets were considered to be random. Results indicate that there was very little repetition error but considerable interplotter error for most frames. Phi-coefficients for x- and y-coordinates, separately, fluctuated across frames. The univariate values for the x-coordinates were similar but slightly less than the multivariate values. The Phi-coefficients for Y, however, were considerably lower than the multivariate values. The multivariate Phi-coefficients for generalizing over three plotters and three repetitions ranged from .82 to .90.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
985.
This paper considers the relationship between stress and cognitive functioning and discusses some of the concepts and methods that may be adopted to examine the relationship between stress and sports performance. It considers only that literature that may be relevant to, or furthers, the understanding of sports performance under competitive stress. One of the most popular approaches has been to explain the relationship in terms of the unidimensional inverted-U hypothesis. The validity of this approach to explaining sports performances in specific situations is discussed and it is generally concluded that the inverted-U hypothesis is too vague and simplistic. The discussion considers multidimensional approaches and discusses the suitability and implications of some more recent and more complex models of stress and performance which are now available in the psychological literature. It is concluded that the relationship between stress and sports performance is an extremely complex one and involves the interaction between the nature of the stressor, the cognitive demands of the task being performed and the psychological characteristics of the individuals performing it.  相似文献   
986.
Endurance running performance in athletes with asthma   总被引:1,自引:0,他引:1  
Laboratory assessment was made during maximal and submaximal exercise on 16 endurance trained male runners with asthma (aged 35 +/- 9 years) (mean +/- S.D.). Eleven of these asthmatic athletes had recent performance times over a half-marathon, which were examined in light of the results from the laboratory tests. The maximum oxygen uptake (VO2max) of the group was 61.8 +/- 6.3 ml kg-1 min-1 and the maximum ventilation (VEmax) was 138.7 +/- 24.7 l min-1. These maximum cardio-respiratory responses to exercise were positively correlated to the degree of airflow obstruction, defined as the forced expiratory volume in 1 s (expressed as a percentage of predicted normal). The half-marathon performance times of 11 of the athletes ranged from those of recreational to elite runners (82.4 +/- 8.8 min, range 69-94). Race pace was correlated with VO2max (r = 0.863, P less than 0.01) but the highest correlation was with the running velocity at a blood lactate concentration of 2 mmol l-1 (r = 0.971, P less than 0.01). The asthmatic athletes utilized 82 +/- 4% VO2max during the half-marathon, which was correlated with the %VO2max at 2 mmol l-1 blood lactate (r = 0.817, P less than 0.01). The results of this study suggest that athletes with mild to moderate asthma can possess high VO2max values and can develop a high degree of endurance fitness, as defined by their ability to sustain a high percentage of VO2max over an endurance race. In athletes with more severe airflow obstruction, the maximum ventilation rate may be reduced and so VO2max may be impaired. The athletes in the present study have adapted to this limitation by being able to sustain a higher %VO2max before the accumulation of blood lactate, which is an advantage during an endurance race. Therefore, with appropriate training and medication, asthmatics can successfully participate in endurance running at a competitive level.  相似文献   
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This paper is in the tradition of social analysis aimed at creatingframeworks to join mass media and public opinion processes (e.g.Clarke and Evans, 1983; Gamson, 1975; Gitlin, 1980; Hall, 1977;Iyengar and Kinder, 1987; Lang and Lang, 1968, 1983; Lippman,1922; Mollotch and Lester, 1974; Noelle-Neuman, 1974; Paletzand Entman, 1981; Shaw and McCombs, 1977; Turner and Paz, 1986).After a brief review of media system dependency (MSD) theory,we illustrate how it may apply to public opinion processes thatentail contested issue ‘value-frames’ (Ball-Rokeachand Rokeach, 1987). In such cases, the media system is directlyimplicated in the negotiation of legitimacy of opposing positionson an issue. Our illustrative case is the abortion issue asit has been played out in the United States over recent decades(Luker, 1984). We focus upon the respective capacities of pro-and anti-abortion movements to control the value-frame of mediacoverage of the issue (Guthrie, 1989). A value-frame may beconceived as ‘... the main substantive theme of a moralityplay’ (Ball-Rokeach and Tallman, 1979) wherein the distinctionbetween ‘good’ and ‘bad’ hangs in thebalance; in this case, between positions on abortion. We suggestthat change in the value-frame of media coverage and publicdiscourse may be understood, at least in part, as an outcomeof change in contestants' MSD relations.  相似文献   
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