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41.
Much of the training of competitive telemark skiers is performed as dry-land exercises. The specificity of these exercises is important for optimizing the training effect. Our aim here was to study the activation of the knee extensor musculature and knee angular displacement during competitive telemark skiing and during dry-land strength training exercises to determine the specificity of the latter. Specificity was analysed with respect to angular amplitude, angular velocity, muscle action and electromyographic (EMG) activity. Five male telemark skiers of national and international standard volunteered to participate in the study, which consisted of two parts: (1) skiing a telemark ski course and (2) specific dry-land strength training exercises for telemark skiing (telemark jumps and barbell squats). The angular displacement of the right knee joint was recorded with an electrogoniometer. A tape pressure sensor was used to measure pressure between the sole of the foot and the bottom of the right ski boot. Electromyographic activity in the right vastus lateralis was recorded with surface electrodes. The EMG activity recorded during maximum countermovement jumps was used to normalize the EMG activity during telemark skiing, telemark jumps and barbell squats. The results showed that knee angular displacement during telemark skiing and dry-land telemark jumps had four distinct phases: a flexion (F1) and extension (E1) phase during the thrust phase of the outside ski/leg in the turn/jump and a flexion (F2) and extension (E2) phase when the leg was on the inside of the turn/jump. The vastus lateralis muscle was activated during F1 and E1 in the thrust phase during telemark skiing and telemark jumps. The overall net knee angular amplitude was significantly greater (P < 0.05) for telemark jumps than for telemark skiing. Barbell squats showed a knee angular amplitude significantly greater than that in telemark skiing (P < 0.05). The mean knee angular velocity of the F1 and E1 phases during telemark skiing was about 0.47 rad x s(-1); during barbell squats, it was about 1.22 rad x s(-1). The angular velocity during telemark jumps was 2.34 and 1.59 rad x s(-1) in the F1 and E1 phase, respectively. The normalized activation level of the EMG bursts during telemark skiing, telemark jumps and barbell squats was 70-80%. In conclusion, the muscle action and level of activation in the vastus lateralis during the F1 and E1 phases were similar during telemark skiing and dry-land exercises. However, the dry-land exercises showed a larger knee extension and flexion amplitude and angular velocity compared with telemark skiing. It appears that an adjustment of knee angular velocity during barbell squats and an adjustment of knee angle amplitude during both telemark jumps and barbell squats will improve specificity during training. 相似文献
42.
To better understand the information needs of young university researchers, an observational study was performed at three universities in Stockholm, Sweden. The observations revealed that most of the researchers used Google for everything, that they were confident that they could manage on their own, and that they relied heavily on immediate access to electronic information. They had very little contact with the library, and little knowledge about the value librarian competence could add. One important conclusion of the project is that librarians have to leave the library building and start working in the research environment, as well as putting some thought into the fact that library use is considered complicated, but Google (etc.) is easy. The findings of this project will influence changes in library services in both near and in a more distant future. 相似文献
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Per Anderhag Patrik Emanuelsson Per-Olof Wickman Karim Mikael Hamza 《International Journal of Science Education》2013,35(18):3141-3160
It is commonly argued that socio-economic inequalities can explain many of the differences in achievement and participation in science education that have been reported among countries and among schools within a country. We addressed this issue by examining (a) the relationship between variables associated with socio-economic background and application frequencies to the Swedish Natural Science Programme (NSP) in upper secondary school and (b) whether there are lower secondary schools in Sweden that seem to compensate for these variables. Data from Statistics Sweden (SCB) covering the whole population of 106,483 ninth-grade students were used to calculate the probability for each student to apply to the NSP. Our results indicate that the variables, such as parental educational level and grades, have explanatory power, but with varying effect for different subpopulations of students. For example, grades in mathematics have a greater impact than grades in science for females' choice of the NSP. The opposite holds for male students. Out of 1,342 schools, 158 deviated significantly from predicted, that is, the students in these schools applied to the NSP in greater or lesser extent than expected. The number of deviating schools is greater than predicted by pure random variation. This suggests that variables of socio-economic background are only a partial explanation of the application frequencies, and that the deviation needs to be investigated further. Our findings suggest that in order to understand why schools deviate positively and so compensate for the socio-economic background of their students, we need to study their practices more closely. 相似文献
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Linda Sprague Martinez Edmond Bowers Amanda J. Reich Uchenna J. Ndulue Albert An Le Flavia C. Peréa 《International Journal of Science Education》2016,38(4):688-699
Participation in inquiry-based science education, which focuses on student-constructed learning, has been linked to academic success. Whereas the benefits of this type of science education are evident, access to such high-quality science curriculum and programming is not equitable. Black and Latino students in particular have less access to supplementary science programming, and fewer opportunities to engage in inquiry-based education. This paper describes outcomes associated with an inquiry-based out-of-school time science education program, Nuestro Futuro: Applied Science Education to Engage Black and Latino Youth (NFASE), which sought to build the capacity of middle school students of color to ‘think’ like health scientists from diverse disciplinary perspectives. The program was designed with the intent of (1) improving student attitudes toward and motivation for science and (2) increasing active and engaged citizenship (AEC). NFASE students explored health inequity and the social determinants of health locally and engaged in developing health promotion, outreach and education efforts targeted to their peers, parents/families, and community. Interest in the program was high overall, but implementation was not without challenges. Although evaluation outcomes indicate that there were no statistically significant changes in science-related attitudes or motivation, students reported significant increases in neighborhood social connection, as well as overall AEC. 相似文献
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Mark Torrance Vibeke Rønneberg Christer Johansson Per Henning Uppstad 《Scientific Studies of Reading》2016,20(5):375-388
It has been hypothesized that students with dyslexia struggle with writing because of a word-level focus that reduces attention to higher level textual features (structure, theme development). This may result from difficulties with spelling and/or difficulties with reading. Twenty-six Norwegian upper secondary students (M = 16.9 years) with weak decoding skills and 26 age-matched controls composed expository texts by keyboard under two conditions: normally and with letters masked to prevent them reading what they were writing. Weak decoders made more spelling errors and produced poorer quality text. Their inter-key-press latencies were substantially longer preword, at word end, and within word. These findings provide some support for the word-level focus hypothesis, although we found that weak decoders were slightly less likely to engage in word-level editing. Preventing reading did not affect differences between weak decoders and controls, indicating that their reduced fluency was associated with production rather than reading difficulties. 相似文献
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Kerstin Göransson Gunilla Lindqvist Nina Klang Gunnlaugur Magnússon Lena Almqvist 《International Journal of Inclusive Education》2013,17(6):559-574
ABSTRACTPrior research shows that special needs educators (SNEs) have had problems defining their occupational roles and jurisdiction, particularly regarding inclusive education. There are two occupational groups of SNEs in Sweden, namely special educational needs coordinators (SENCOs) and special education teachers. In this paper, we use the collective name SNEs to refer to both groups. Here, results from a total population study of Swedish SNEs are presented (N?=?3367, response rate 75%). The aim is to explore differences in SNEs’ interpretation of school difficulties and if these differences are influenced by SNEs’ employment in different parts of the school organisation. Statistical cluster-analysis was used to categorise SNEs into five distinct groups based on how they view the problems of pupils in school difficulties. Key concepts employed in the analysis are, primarily organisational vs occupational governance in relation to professional jurisdiction. Findings suggest that SNEs are less unanimous in their views of school problems, than prior research indicates. The variance is partly due to where they work in the school organisation, but we also find indications that different groups of SNEs experience different forms of governance with regard to their professionalism. The results are important due to the scope of the data and method of analysis as well as the illustrated variance of professional values and situations of SNEs and the potential consequences for the development of inclusive education. 相似文献
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Johnny Nilsson Sandor Csergö Lennart Gullstrand Per Tveit Per Egil Refsnes 《Journal of sports sciences》2013,31(11):939-945
The aim of this study was to examine work-time profiles, blood lactate concentrations and perceived exertion among Greco-Roman wrestlers in the 1998 World Championship. Forty-two senior wrestlers from nine nations were studied in 94 matches. Each match was recorded with a video camera (Panasonic AG 455, film rate: 25 Hz) and analysed for duration of work (wrestling) and rest (interrupt) periods. Blood lactate concentration was determined with an electrochemical device (Analox P-LM5) and a rating of perceived exertion scale (Borg) was used to estimate general exertion and exertion in the extremity and trunk muscles. The mean duration of the matches was 427 s (range 324-535 s), with mean durations of work and rest of 317 and 110 s, respectively. The mean periods of work and rest were 37.2 and 13.8 s, respectively. Mean blood lactate concentration was 14.8 mmol · l -1 (range 6.9-20.6). The difference in mean blood lactate concentration between the first- and final-round matches was not significant ( P > 0.05). Blood lactate concentration was significantly higher ( P ? 0.04) in matches of long duration than in those of short duration. The mean general rating of perceived exertion for all matches was 13.8 according to the scale used. Most of the wrestlers (53.3%) perceived exertion to be highest in the flexors of the forearm, followed by the deltoids (17.4%) and the biceps brachii muscles (12.0%). In addition to a relatively high rating of perceived exertion in the arm muscles, this indicates a high specific load on the flexor muscles of the forearm. 相似文献
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