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51.
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   
52.
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   
53.
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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The many challenges faced by health sciences libraries of all types and sizes often require innovative solutions. When an innovative solution involves calculated risk taking, the approach is called intrapreneurial. At the University of Miami School of Medicine, an intrapreneurial approach solved the fiscal problems of the biomedical communications unit. The Louis Calder Memorial Library inherited these problems when the Department of the Library and Biomedical Communications was created in the early 1980s. In this paper, two intrapreneurial programs are described, and the benefit and suitability of this management style to information services are demonstrated.  相似文献   
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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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S. Ramasesha 《Resonance》2009,14(8):782-798
Efficient lighting and display have become important concerns in the energy-starved modern world. This has led to new paradigms in lighting and display technologies. Organic molecules provide a new class of active materials for such technologies. This article gives the basic science behind the design of such molecular materials used in displays and lighting.  相似文献   
60.
The most frequently requested accommodation among students with learning disabilities (LD) in postsecondary settings is extended test time. The frequency with which this accommodation is requested and granted compels disability service providers to become knowledgeable about the factors that influence the need for, and appropriateness of, the accommodation. Moreover, the synthesis of these factors becomes the basis for determining if the accommodation is reasonable under federal law. The purpose of this article is to present a step‐by‐step model to be used as a decision‐making process when considering the accommodation of extended test time for postsecondary students with LD. The model is designed to assist disability service providers in the analysis and synthesis of information collected from (1) the student's diagnostic evaluation, (2) the course or classroom test to be accommodated, and (3) student interviews. A list of diagnostic tests from the four most frequently administered test batteries used with adults is provided, along with a concise explanation of how characteristics of LD impact reading, writing, and math, and relate to the need for extended time. This information can be used to determine if extended test time is a reasonable accommodation and to estimate how much additional time to provide.  相似文献   
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