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991.
Public libraries have a huge potential to be creators and facilitators of social innovation in communities and society. Qualitative research based on interviews with 27 librarians showed that social innovation in libraries can take the form of educational and cultural activities, leisure and networking activities and social support services. The main goal of the research was to find out what factors support and make these innovations difficult in public libraries. A four-layer model of barriers and stimulators for social innovation is presented, which includes structural, local, organizational and personnel levels. The model could serve to inform librarians, their stakeholders and governments about all levels of barriers and stimulators connected to innovation of library services and social re-positioning of public libraries in the future.  相似文献   
992.
993.
A comprehensive methodology for selecting the world’s scientific periodicals that are necessary to carry out research on specific natural science and technical directions is given based on the use of citation analysis taking into account both citation indexes of selected publications in specialized journals and their citation of specialized journals. A list of world journals and other publications is obtained based on which it is suggested to create the corresponding scientific and information environment.  相似文献   
994.
995.
The triple jump is a demanding field event in which a jumper must tolerate extremely high impact forces while maintaining high horizontal speed. The present study was designed to clarify the mechanical loading characteristics and the role of neuromuscular function in the triple jump. Seven national triple jumpers (4 males, 3 females) volunteered to perform 3-6 jumps. The mean best performances were 14.32+/-0.45 m and 11.90+/-0.28 m for males and females, respectively. The three longest triple jumps for each jumper were selected for final analysis. The mean contact times were 0.139 s (hop), 0.157 s (step) and 0.177 s (jump). The largest ground reaction forces were observed in the step (15.2 times body weight), while the highest peak pressures were recorded under the heel and forefoot. The plantar pressure of the lateral side of the forefoot was highly related to the length of the triple jump (P < 0.05-0.01). In addition, electromyograms of both legs Suggested that mechanical loading places high demands on the neuromuscular system, as characterized by the high rate of activation in the pre-activity phase followed by high eccentric activity. Thus, the high activities of the gastrocnemius, vastus lateralis and hip extensor muscles seem to play an important role in preventing unnecessary yielding of the jumper during the braking phase.  相似文献   
996.
When cycling on level ground at a speed greater than 14 m/s, aerodynamic drag is the most important resistive force. About 90% of the total mechanical power output is necessary to overcome it. Aerodynamic drag is mainly affected by the effective frontal area which is the product of the projected frontal area and the coefficient of drag. The effective frontal area represents the position of the cyclist on the bicycle and the aerodynamics of the cyclist-bicycle system in this position. In order to optimise performance, estimation of these parameters is necessary. The aim of this study is to describe and comment on the methods used during the last 30 years for the evaluation of the effective frontal area and the projected frontal area in cycling, in both laboratory and actual conditions. Most of the field methods are not expensive and can be realised with few materials, providing valid results in comparison with the reference method in aerodynamics, the wind tunnel. Finally, knowledge of these parameters can be useful in practice or to create theoretical models of cycling performance.  相似文献   
997.
In this study, we investigated a new method of training for maximal strength and flexibility, which included exertion with superimposed vibration (vibratory stimulation, VS) on target muscles. Twenty‐eight male athletes were divided into three groups, and trained three times a week for 3 weeks in one of the following conditions: (A) conventional exercises for strength of the arms and VS stretching exercises for the legs; (B) VS strength exercises for the arms and conventional stretching exercises for the legs; (C) irrelevant training (control group). The vibration was applied at 44 Hz while its amplitude was 3 mm. The effect of training was evaluated by means of isotonic maximal force, heel‐to‐heel length in the two‐leg split across, and flex‐and‐reach test for body flexion. The VS strength training yielded an average increase in isotonic maximal strength of 49.8%, compared with an average gain of 16% with conventional training, while no gain was observed for the control group. The VS flexibility training resulted in an average gain in the legs split of 14.5 cm compared with 4.1 cm for the conventional training and 2 cm for the control groups, respectively. The ANOVA revealed significant pre‐post training effects and an interaction between pre‐post training and ‘treatment’ effects (P< 0.001) for the isotonic maximal force and both flexibility tests. It was concluded that superimposed vibrations applied for short periods allow for increased gains in maximal strength and flexibility.  相似文献   
998.
Abstract

Three hundred male subjects, assigned in systematic rotation to five experimental groups (N = 60 in each) which differed in amount of distribution of practice, were tested on a discrete-trial motor learning task, the peg turn. All subjects were given 120 practice trials (60 trials a day), on two days separated by a 48-hour rest. Even though the peg turn task is inherently distributed, reminiscence did occur when the massing was made as large as practically possible. The amount of reminiscence depended upon the stage of practice. Warm-up decrement occurred in the peg turn under both massed and distributed practice conditions; the longer the rest, the greater the amount. Performance of the task under nonrhythmical conditions reduced the development of “set” during practice and thus decreased the amount of warm-up decrement after rest. Increased amounts of massing did have a deleterious effect on performance, but did not reduce the amount learned.  相似文献   
999.
Underfat individuals have been neglected as a malnourished population in terms of redox homeostasis. The aim of the present study was to evaluate the effect of body composition on redox homeostasis at rest and in response to exercise. Underfat, lean and overfat women, classified according to their BMI and body fat percentage, participated in the study and were subjected to an acute session of eccentric exercise. With regard to muscle function and damage, a significant group × time interaction was found for range of motion (P < .01), isometric peak torque at 90° (P < .01), delayed onset muscle soreness (P < .01) and creatine kinase (P < .05), with the lean group generally exhibiting faster recovery compared to the underfat and overfat groups. With regard to redox homeostasis, a significant group × time interaction was found for F2-isoprostanes, protein carbonyls and glutathione (P < .01 for all biomarkers), with the underfat and overfat groups exhibiting increased resting oxidative stress levels and lower exercise-induced reactive species production . In conclusively, our data underline the importance of normal body composition for redox homeostasis, since underfat and overfat women demonstrate a similar pattern of redox disturbances both at rest and in response to exercise.  相似文献   
1000.
A new residential college and a faculty-in-residence program demonstrate how student affairs educators and academic faculty at one institution have collaborated to create transformational learning experiences for their students.  相似文献   
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