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31.
Chaos theory, informational needs, and natural disasters   总被引:2,自引:0,他引:2  
This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning.  相似文献   
32.
Cerebral activity, as reflected by power in the alpha waveband (8-13 Hz), was examined prior to the performance of three tasks with different effort and accuracy requirements. The study aimed to further investigate changes in activity observed in an earlier study in which expert karate performers exhibited significant increases in alpha band power during preparation for a training task. In contrast to the earlier research, the high effort task produced a significant decrease in 'alpha' power prior to performance. 'Alpha' power prior to the high accuracy task showed significant differences mediated by the outcome. Successful performance was preceded by higher levels of 'alpha' power than unsuccessful attempts. The reported use of a cognitive strategy on the first task produced a significant difference in activity, lower alpha power being associated with the use of such a technique.  相似文献   
33.
This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO2) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO2 and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO2 and HR were measured continuously during the postexercise period until baseline VO2 was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p greater than .05). Mean (+/- SD) values were 9.2 +/- 3.3 and 10.4 +/- 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p greater than .05) between the upper body (22.9 +/- 13.7 min) and lower body (24.2 +/- 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO2 or quantity of active muscle mass associated with these two types of exercise.  相似文献   
34.
Data from the International Social Survey Program indicate considerablevariation in the desire of respondents for increased spendingon the environment in Australia, Austria, Great Britain, theUnited States, and West Germany. This paper explores this variationwith the following objectives: (1) to determine the extent towhich the social bases of environmental concern are consistentacross nations; (2) to determine how the issue of the environmenthas been politicized in the five industrialized nations, focusingon the association of Old Leftist concerns and environmentalconcern; and (3) to determine the extent to which the socialbases of environmental concern can explain the cross-nationalvariation. The study usesa regression analysis, testing variablesrepresenting the social bases of environmental concern frompast research in the United States, a scale representing commitmentto the platform of the Old Left, and dummy variables for eachcountry. The results show that the social bases of environmentalconcern are the same in the five countries studied, includinga consistent positive association of Old Leftism with environmentalconcern. However, substantial variation between countries inthe overall level of concern remains. Potential sources of theremaining variation are examined.  相似文献   
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PUBLIC AND ELITE ATTITUDES TO ENVIRONMENTAL ISSUES   总被引:1,自引:0,他引:1  
This paper puts the environment into perspective. Politiciansand commentators see the environment as yesterday's issue, forgettingthat the core of environmental activists is still double thelevel of just five years ago. International comparisons stretchingfrom Poland to New Zealand are made, examining the public'senvironmental behavior, attitudes and values. Using Great Britainas a case study, detailed comparisons are made between the attitudesof the general public with journalists, the financial community,captains of industry, and Members of Parliament and the latterthen compared with Members of the European Parliament. The publicis demanding action by companies and by governments on environmentalissues and has little faith in either to take corrective action.  相似文献   
38.
The purpose of this investigation was to describe the morphological parameters that characterize elite age group divers. Comparisons are made to normative age group data from the Coquitlam Growth Study and the constancy of important characteristics from age group to age group is examined. Data were collected on 27 male and 28 female elite divers who participated in the 1990 North American Age Group Diving Championships. Body build, body composition and skinfold corrected diameters were determined from 36 anthropometric parameters and analysed by ANOVA, t-test and Phantom z-scores procedures. All age groups except the 14- to 15-year-old males were significantly (P < or = 0.05) shorter than their norms but recorded higher androgyny index values. The estimated relative muscle mass increased significantly (P < or = 0.05) with age for males at all ages (40.8-46.3%). The 16- to 18-year-old females had a significantly (P < or = 0.05) larger relative muscle component compared to the younger age groups (40.1-38.4%). When normalized for height, active tissue development of the extremities was comparable between the sexes except in the forearm. The results indicate that at all age levels short stature is an important characteristic for divers. Analysis of regional active tissue development provides further insight into sport-specific prerequisites for success at elite levels.  相似文献   
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