排序方式： 共有40条查询结果，搜索用时 421 毫秒
31.
Dario SAMBUNJAK Mirjana HUIĆ Darko HREN Milica KATIĆ Ana MARUŠIĆ Matko MARUŠIĆ 《Learned Publishing》2009,22(1):57-70
Scholarly journals, especially in non‐English‐speaking countries, may perform very different functions depending on whether they are published for national or international audiences. Four hundred and sixty‐six academic physicians and non‐academic general practitioners in Croatia were surveyed on their knowledge about two Croatian medical journals: Lije?ni?ki vjesnik (published in Croatian) and Croatian Medical Journal (published in English). The physicians were also surveyed about the importance of all national and international journals published in Croatia, and the types of articles they thought should be published in these journals. More respondents rated national (n = 329, 72.6%) than international journals (n = 275, 63.5%, P < 0.001, Wilcoxon test) as very important for the medical profession. On the other hand, publishing in international journals was more often rated as important than publishing in national journals (n = 184, 42.5% vs. n = 125, 27.8%; P < 0.001, Wilcoxon test). Guidelines for clinical practice were rated as the most important publication item in national journals, and original scientific articles in international journals. 相似文献
32.
In this study we map out the large-scale structure of citation networks of science journals and follow their evolution in time by using stochastic block models (SBMs). The SBM fitting procedures are principled methods that can be used to find hierarchical grouping of journals that show similar incoming and outgoing citations patterns. These methods work directly on the citation network without the need to construct auxiliary networks based on similarity of nodes. We fit the SBMs to the networks of journals we have constructed from the data set of around 630 million citations and find a variety of different types of groups, such as communities, bridges, sources, and sinks. In addition we use a recent generalization of SBMs to determine how much a manually curated classification of journals into subfields of science is related to the group structure of the journal network and how this relationship changes in time. The SBM method tries to find a network of blocks that is the best high-level representation of the network of journals, and we illustrate how these block networks (at various levels of resolution) can be used as maps of science. 相似文献
33.
34.
35.
36.
Susanne A. Tittlbach Darko Jekauc Steffen C. E. Schmidt Alexander Woll Klaus Bös 《European Journal of Sport Science》2017,17(8):1090-1099
Objectives: This study’s aims were to describe the development of physical activity, physical fitness (PF), subjective (physical complaints (PC)) and objective (Body mass index (BMI)) health measures and to examine the relationship between the development trajectories. In addition, the study also aimed to assess the influence of sociodemographic determinants (age, sex, socioeconomic status (SES)) in German adults over a period of 18 years. Methods: The longitudinal study population comprises of 721 men and women, aged 33–76 years over the study period. There was self-report of physical activity and PC and testing of physical fitness and BMI in each study year (1992, 1997, 2002 and 2010). Latent growth curve models were used to analyse the development. Results: Physical activity slightly increased while fitness, PC and BMI worsened over the course of 18 years. Sex, age and SES play important roles concerning physical activity, fitness and health. Several integrative associations could be detected between physical activity, fitness, PC and BMI as well as their trajectories. In particular, high initial levels of physical activity and fitness protect from high PC and BMI.The slope of physical activity was not significantly associated with slopes of fitness, PC and BMI. However, increase of fitness resulted in decrease of PC. Conclusions: A general positive development regarding the amount of physical activity could be detected. However, if it is only an unsystematic increase of physical activity, this is not in itself enough to achieve health benefits. The strengthening of fitness should be focused when increasing physical activity, since only then a health benefit is possible. 相似文献
37.
38.
39.
40.