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31.
In Western societies scientists are increasingly expected to seek media exposure and cooperate with industry. Little attention
has been given to the way such expectations affect the role of scientific experts in society. To investigate scientists’ own
perspectives on these issues eight exploratory, in-depth interviews were conducted in Denmark with reputable nutrition scientists.
Additionally, eight interviews were held with ‘key informants’ from the field of nutrition policy. It was found that nutrition
scientists experience two dilemmas: first, between their aspiration to make a collective impact on public health and the powerful
incentives of each to appear frequently in the media with new messages; second, between their need to cooperate with the food
industry for financial reasons and their fear that this may compromise their independence and scientific integrity. It is
argued that the dilemmas identified in this study should be dealt with openly by the relevant groups of scientists. 相似文献
32.
The aim of this study was to examine the effects of muscle-tendon length on joint moment and power during maximal sprint starts. Nine male sprinters performed maximal sprint starts from the blocks that were adjusted either to 40 degrees or 65 degrees to the horizontal. Ground reaction forces were recorded at 833 Hz using a force platform and kinematic data were recorded at 200 Hz with a film camera. Joint moments and powers were analysed using kinematic and kinetic data. Muscle - tendon lengths of the medial gastrocnemius, soleus, vastus medialis, rectus femoris and biceps femoris were calculated from the set position to the end of the first single leg contact. The results indicated that block velocity (the horizontal velocity of centre of mass at the end of the block phase) was greater (P < 0.01) in the 40 degrees than in the 65 degrees block angle condition (3.39 +/- 0.23 vs. 3.30 +/- 0.21 m . s(-1)). Similarly, the initial lengths of the gastrocnemius and soleus of the front leg in the block at the beginning of force production until half way through the block phase were longer (P < 0.001) in the 40 degrees than in the 65 degrees block angle condition. The initial length and the length in the middle of the block phase were also longer in the 40 degrees than in the 65 degrees block angle condition both for both the gastrocnemius (P < 0.01) and soleus (P < 0.01-0.05) of the rear leg. In contrast, the initial lengths of the rectus femoris and vastus medialis of the front leg were longer (P < 0.05) in the 65 degrees than in the 40 degrees block angle condition. All differences gradually disappeared during the later block phase. The peak ankle joint moment (P < 0.01) and power (P < 0.05) during the block phase were greater in the 40 degrees than in the 65 degrees block angle condition for the rear leg. The peak ankle joint moment during the block phase was greater (P < 0.05) in the 40 degrees block angle for the front leg, whereas the peak knee joint moment of the rear leg was greater (P < 0.01) in the 65 degrees block angle condition. The results suggest that the longer initial muscle-tendon lengths of the gastrocnemius and soleus in the block phase at the beginning of force production contribute to the greater peak ankle joint moment and power and consequently the greater block velocity during the sprint start. 相似文献
33.
The effects of query structures and query expansion (QE) on retrieval performance were tested with a best match retrieval system (InQuery1). Query structure means the use of operators to express the relations between search keys. Six different structures were tested, representing strong structures (e.g., queries with facets or concepts identified) and weak structures (no concepts identified, a query is a bag of search keys). QE was based on concepts, which were first selected from a searching thesaurus, and then expanded by semantic relationships given in the thesaurus. The expansion levels were (a) no expansion, (b) a synonym expansion, (c) a narrower concept expansion, (d) an associative concept expansion, and (e) a cumulative expansion of all other expansions. With weak structures and Boolean structured queries, QE was not very effective. The best performance was achieved with a combination of a facet structure, where search keys within a facet were treated as instances of one search key (the SYN operator), and the largest expansion. 相似文献
34.
Exploring the link between culture and strategy in media organisations: The cases of the BBC and CNN
Dr. Lucy Küng 《媒体管理杂志》2013,15(2):100-109
Abstract This study employs participant observation methodology to examine the U.S. broadcast industry's cognitions of its external environment. Previous research has documented a tendency among industry participants to operate under outdated mental models of their environment. This tendency ‐ labeled ‘cognitive inertia’ ‐ provides the analytical framework for this study. The results provide indications that broadcasters operate under what appear to be outdated mental models of their external environment, with broadcasters appearing to pay inadequate attention to competing program sources and failing to account for the changing demographic composition of the television audience. However, these conclusions are tempered by the broadcast industry's dual‐product marketplace characteristics, wherein cognitions that would appear to reflect inadequate assessment of the content market may in fact reasonably reflect the contemporary realities of the audience market. 相似文献
35.
36.
Jäger 《Wiener klinische Wochenschrift Education》2007,2(3):195-195
Ohne Zusammenfassung 相似文献
37.
Triin Rääsk Kenn Konstabel Jarek Mäestu Evelin Lätt Toivo Jürimäe Jaak Jürimäe 《Journal of sports sciences》2015,33(16):1649-1657
We examined the tracking of physical activity (PA) measured by accelerometers and subjective self- and parental reports in normal weight and overweight and obese pubertal boys over two-year period. In total, 156 boys with mean (±SD) age of 11.53 ± 0.76 at baseline and with mean age of 13.94 ± 0.74 at 2 year follow-up were studied. At baseline and approximately two years later, the boys completed self-report questionnaire and wore an accelerometer for seven consecutive days. On the basis of first year assessment’s body mass index (BMI), the children were grouped as normal weight and overweight and obese groups according to BMI cut-offs. Tracking correlations of objectively measured PA and subjectively measured PA were fairly similar across the 12–14 year-old-boys weight groups over two year period. Tracking correlations of objectively measured PA and subjectively measured PA were not significantly different over two-year period between both BMI groups. The results of the study show that pubertal boys objectively measured PA decreased over two-year period and so the boys started to be less active in their pubertal period. 相似文献
38.
Martin K. Klämpfl Philipp B. Philippen Babett H. Lobinger 《Journal of sports sciences》2015,33(7):655-664
The yips is considered a task-specific movement disorder. Its estimated prevalence, however, is high compared to similar neurological movement disorders, possibly resulting from previous studies’ restriction of samples based on skill level, and self-report bias. Alternatively, this high prevalence might be an indication of additional aetiologies, for example the influence of previously played racket sports. We estimated the prevalence of the putting yips across the skill range, using self-reports in one study and a screening test in a second study. We explored if previously played sports matter for the development of the yips. In study 1, yips prevalence (N = 1,306) and golfers’ sports biographies (n = 264) were examined via two online surveys, in which golfers indicated if they were yips-affected. In study 2, golfers (N = 186) putted in a standardised putting test while kinematic and performance measures were recorded. Prevalence was estimated via a kinematic threshold. Sports biographies (n = 119) were obtained via an online survey. Prevalence of currently yips-affected golfers was 22.4% in study 1 and 16.7% in study 2. In both studies, more yips-affected than unaffected golfers had experience in playing racket sports. Yips prevalence remained higher than previously estimated prevalence of other movement disorders but decreased when the whole skill range including professionals and novices was considered. Future studies should use the kinematic screening test instead of self-reports to detect the yips and further investigate the influence of previously played racket sports. 相似文献
39.
Johanna Tevaniemi Jenni Poutanen Riitta Lähdemäki 《New Review of Academic Librarianship》2015,21(3):304-324
This article presents a case of co-designed temporary learning spaces at a Finnish academic library, together with the results of a user-survey. The experimental development of the multifunctional spaces offered an opportunity for the library to collaborate with its parent organisation thus broadening the role of the library. Hence, library can be seen as a third player facilitating learning spaces. Additionally, the library's own expertise was strengthened through successful cooperation with the undergraduate students and other actors. The results support prior research, where studying in the library is target-oriented differing from other learning spaces in providing support and resources. 相似文献
40.
This study investigated development of the Big Five personality traits from early childhood into adulthood. An initial group of 137 Swedish children were assessed eight times between ages 2 and 29 years. Initial decreases in extraversion leveled off in early adulthood; agreeableness and conscientiousness increased from ages 2 to 29; neuroticism initially increased, leveled off in later childhood and adolescence, and decreased throughout early adulthood; while openness to experience showed an initial increase, then decreased and leveled off in early adulthood. Individual developmental trajectories varied significantly, particularly in relation to gender. Personality traits became increasingly stable, and the fact that childhood scores predicted scores in adulthood indicated that personalities are fairly stable across this portion of the life span. 相似文献