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151.
In our paper we present an experimental study which investigated the possibility to project the need for information specialists serving knowledge workers in knowledge industries on the basis of an average university library serving their counterparts at a university. Information management functions, i.e. functions and processes related to information evaluation, acquisition, metadata creation, etc., performed in an average university library are the starting point of this investigation. The fundamental assumption is that these functions do not only occur in libraries but also in other contexts like, for instance, in knowledge industries. As a consequence, we try to estimate the need for information professionals in knowledge industries by means of quantitative methods from library and information science (Library Planning Model) and economics (input output analysis, occupational analysis). Our study confirms the validity of our assumption. Accordingly, the number of information specialists projected on the basis of university libraries is consistent with their actual number reported in national statistics. However, in order to attain a close fit, we had to revise the original research model by dismissing the split-up of information specialists into reader services and technical services staff.  相似文献   
152.
Abstract

In this study, we examined the effect of muscle temperature (T m) on adenosine triphosphate (ATP) and phosphocreatine utilization in single muscle fibres during the development of maximal power output in humans. Six male participants performed a 6-s maximal sprint on a friction-braked cycle ergometer under both normal (T m = 34.3°C, s = 0.6) and elevated (T m = 37.3°C, s = 0.2) muscle temperature conditions. During the elevated condition, muscle temperature of the legs was raised, passively, by hot water immersion followed by wrapping in electrically heated blankets. Muscle biopsies were taken from the vastus lateralis before and immediately after exercise. Freeze-dried single fibres were dissected, characterized according to myosin heavy chain composition, and analysed for ATP and phosphocreatine content. Single fibres were classified as: type I, IIA, IIAX25 (1 – 25% IIX isoform), IIAX50 (26 – 50% IIX), IIAX75 (51 – 75% IIX), or IIAX100 (76 – 100% IIX). Maximal power output and pedal rate were both greater (P < 0.05) during the elevated condition by 258 W (s = 110) and 22 rev · min?1 (s = 6), respectively. In both conditions, phosphocreatine content decreased significantly in all fibre types, with a greater decrease during the elevated condition in type IIA fibres (P < 0.01). Adenosine triphosphate content was also reduced to a greater (P < 0.01) extent in type IIA fibres during the elevated condition. The results of the present study indicate that after passive elevation of muscle temperature, there was a greater decrease in ATP and phosphocreatine content in type IIA fibres than in the normal trial, which contributed to the higher maximal power output.  相似文献   
153.
Abstract

This study aimed to examine the effects of application of kinaesthetic tapes on plantarflexor muscle performance. We hypothesised that taping of the triceps surae muscle would improve plantarflexor muscle strength and endurance with no significant effect on drop jump performance. Using a repeated-measures design, all performance measures were obtained in 24 volunteers on two separate occasions: without tapes and after application of kinaesthetic tapes. Performance tests included measurements of isometric plantarflexor muscle strength and the associated electromyographic activity of the gastrocnemius muscle, an isokinetic fatigue resistance test (30 contractions at 180° · s?1) and assessments of drop jump performance. The taping-intervention was associated with an increase in gastrocnemius electromyographic activity. However, significant increases in isometric strength were only found at fully dorsiflexed ankle positions (+12% at ?20°). Strength gains were negatively correlated to baseline strength (r = ?.58). The intervention did not affect the results of the isokinetic fatigue and drop jump tests. The application of kinaesthetic tapes over the triceps surae muscle promotes an increase in isometric strength and gastrocnemius muscle activity. Our data suggest that these effects are joint-angle dependent and more prominent in weaker individuals. By contrast, the taping-intervention improves neither drop jump performance nor muscular endurance.  相似文献   
154.
155.
Researchers from Mid Sweden University and Kalmar University organised surveys on reading skills in Swedish municipalities. This paper will focus on the surveys made in four municipalities between 2002 and 2007. All students in grade 8 in these four municipalities participated in the surveys--in total 16,287 students. These surveys included a reading test for the students and information about the students collected from the teachers, including participation in instruction in Swedish as a second language and in their mother tongues. Students of immigrant origin in Sweden are offered the possibility to participate in instruction in Swedish as a second language and in instruction in the student's mother tongue. No obvious trends over time in the participation in Swedish as a second language and mother tongue instruction were found in the four municipalities on the tests we gave, in spite of national trends. There was no difference in results on the reading tests in Swedish between those students who participated in mother tongue instruction and those who did not, but there was a difference in test results between those who participated in Swedish as a second language and those who did not. Those who did not participate (in Swedish as a second language instruction) did, on average, score higher on the test. When different language groups are compared, it can be noted that a majority in all groups of immigrant students neither participate in Swedish as a second language nor in mother tongue instruction. However, there are important differences between boys and girls and between language groups. Girls seemed to be more willing than boys to participate in voluntary mother tongue instruction, while boys more often than girls had to participate in compulsory lessons in Swedish as a second language.  相似文献   
156.
To acknowledge both conceptual and situational factors, children’s understanding of the Earth was considered from three angles: 1, the perspective as the physical point or direction from which something is seen or depicted; 2. conceptual frameworks; 3. the relevance of explanations in a situation. Fourteen children were interviewed individually in front of a poster of a satellite photo of the Earth. The interviews were semi-structured and focused on what the children understood was depicted in the poster and if they had seen the Earth. The effect of choice of perspective was demonstrated by children who only talked about how the Earth could be seen from space. The need to relate different conceptual frameworks became apparent with children, who meant that the Earth was situated in the direction of the sky. Different understandings of the relevance of an explanation were detected when the interviewer talked from the perspective in the room, but children talked about the perspective in the present poster. The results indicate that not only both conceptual frameworks and understanding of perspectives play a part when students encounter questions related to the concept of Earth, but also the students’ judgments of the relevance of different explanations in a situation.  相似文献   
157.
This study examined if accelerometer-based assessments of physical activity were responsive to changes in physical activity level commensurate with performing structured versus unstructured activity in youth. Youth (6–16 years; N = 206) participated in a simulated after-school program that included structured and unstructured games on four occasions over a 3-year period. Recruitment occurred in 2007/2008 and data collection ended in 2011. Participants wore an Actigraph GT1M accelerometer on the hip. The Evenson cut-points were used to determine the time spent in each physical activity intensity, and standardized response means (SRM) were calculated and converted to standard effect sizes to be interpreted according to Cohen’s guidelines. SRMs ranged from trivial (0.16) to high (2.07), with the majority (75%) being classified as moderate or high. Our findings suggest that accelerometry was sensitive to differences in physical activity associated with structured compared to unstructured play, supporting the utility of accelerometry in evaluating activity-promoting interventions.  相似文献   
158.
Purpose: The purposes of this article are to: (a) describe the rationale and development of the Youth Compendium of Physical Activities (Youth Compendium); and (b) discuss the utility of the Youth Compendium for audiences in research, education, community, health care, public health, and the private sector. Methods: The Youth Compendium provides a list of 196 physical activities (PA) categorized by activity types, specific activities, and metabolic costs (youth metabolic equivalents of task [METy]) as measured by indirect calorimetry. The utility of the Youth Compendium was assessed by describing ways in which it can be used by a variety of audiences. Results: Researchers can use METy values to estimate PA levels and determine changes in PA in intervention studies. Educators can ask students to complete PA records to determine time spent in physical activities and to identify health-enhancing activities for classroom PA breaks. Community leaders, parents, and health care professionals can identify activity types that promote healthful behaviors. Public health agencies can use the METy values for surveillance and as a resource to inform progress toward meeting national physical activity guidelines. Applications for the private sector include the use of METy in PA trackers and other applications. Conclusion: The National Collaborative on Childhood Obesity Research Web site presents the Youth Compendium and related materials to facilitate measurement of the energy cost of nearly 200 physical activities in children and youth. The Youth Compendium provides a way to standardize energy costs in children and youth and has application for a wide variety of audiences.  相似文献   
159.
Including vulnerable groups of students such as students with learning disabilities in mainstream school research, require ethical considerations and questionnaire adaptation. These students are often excluded, due to low understanding or methodologies generating inadequate data. Students with disability need be studied as a separate group and provided accessible questionnaires. This pilot study aims at developing and evaluating student self-reported measures, rating aspects of student experiences of school-based Physical Education (PE). Instrument design, reliability and validity were examined in Swedish secondary school students (n = 47) including students, aged 13, with intellectual disability (n = 5) and without impairment and test–retested on 28 of these students. Psychometric results from the small pilot-study sample were confirmed in analyses based on replies from the first wave of data collection in the main study (n = 450). Results show adequate internal consistency, factor structure and relations between measures. In conclusion, reliability and validity were satisfactory in scales to measure self-efficacy in general, in PE, and aptitude to participate. Adapting proxy ratings for functioning into self-reports indicated problems. Adequacy of adjustments made were confirmed and a dichotomous scale for typical/atypical function is suggested for further analyses.  相似文献   
160.
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