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561.
The Danish e-commerce strategy is a highly ambitious effort to become the world's leading IT nation. Instead of a production-led approach aimed at stimulating domestic hardware and software production, Denmark has pursued a demand-oriented approach focused on promoting the widespread adoption of e-commerce in the Danish society. The Danish government has developed a number of e-commerce initiatives via public-private sector partnerships--an approach we refer to as "governance." So far, it appears that Denmark has been successful in promoting business-to-business (B2B) e-commerce, with a number of Danish companies being global leaders in the use of B2B applications. On the other hand, Denmark has had less success in achieving widespread use of business-to-consumer (B2C) e-commerce. This article analyzes the Danish national environment for e-commerce, discusses four sets of governance initiatives aimed at the development of e-commerce, and analyzes the reasons for its success in B2B and relative failure in B2C adoption.  相似文献   
562.
ABSTRACT

Despite literature highlighting numerous risks to the healthy psychosocial development of youth elite academy soccer players, little of this research is based on high-quality research designs. This study employed a prospective longitudinal cohort design to track psychosocial outcomes of academy involvement within male youth elite soccer players (n = 33, U12-U16 age groups) compared to age-matched soccer-active school pupils (n = 44) over 12 months. Participants completed questionnaires assessing the most commonly raised psychosocial concerns at four equally spaced data collection periods (T1–T4). Repeated measures multivariate analysis of variance (MANOVAs) indicated that, over the year, both groups reported a healthy and improving stress and recovery balance, as well as positive and stable needs satisfaction and physical, psychological and social well-being. Academy players reported stable positive school-related quality of life, whereas school pupils reported increases from T3 to T4. Academy players reported consistent significantly higher total athletic identity and exclusivity of identity. Findings suggest that many concerns around negative psychosocial impacts of soccer academy involvement did not materialise in this context. However, heightened athletic identities remained a concern.  相似文献   
563.
ABSTRACT

The aim was to investigate how measurements of the lipidome differ according to the level and intensity of physical activity in a population at high risk of type 2 diabetes (T2DM). A targeted metabolomics platform provided quantitative molecular data on lipid species. Linear regression examined the associations between plasma lipid concentrations, particle size and time spent in objectively measured physical activity intensity domains, in increments of 500 counts per minute (cpm) (up to >4500 cpm (~>5.6METs)). Results are presented as % difference in the concentration (lower/higher) or particle size (smaller/larger) per 10 min of activity within each intensity. Five hundred and nine participants were included. Time spent in the lowest physical activity intensity domain (<500 cpm) was unfavourably associated with VLDL (2%), HDL (?2%) and Apolipoprotein A-1 particle concentrations (?2%) and HDL diameter (?2%). Conversely, time spent in intensities ≥1000 cpm were favourably associated with HDL subclass concentrations; with stronger associations seen at moderate intensities (2000-3999 cpm (~4.5METs)). For Apolipoprotein-B concentration and VLDL particle concentration and size, a negative association was consistently observed at the highest physical activity intensity only. If these associations are causal, HDL subclasses appear sensitive to light-intensities whereas only the high category of physical activity intensity was consistently associated with VLDL subclasses.  相似文献   
564.
Abstract

The aim of this study was to assess agreement between peak and mean force methods of quantifying force asymmetry during the countermovement jump (CMJ). Forty-five men performed four CMJ with each foot on one of two force plates recording at 1,000 Hz. Peak and mean were obtained from both sides during the braking and propulsion phases. The dominant side was obtained for the braking and propulsion phase as the side with the largest peak or mean force and agreement was assessed using percentage agreement and the kappa coefficient. Braking phase peak and mean force methods demonstrated a percentage agreement of 84% and a kappa value of 0.67 (95% confidence limits: 0.45–0.90), indicating substantial agreement. Propulsion phase peak and mean force methods demonstrated a percentage agreement of 87% and a kappa value of 0.72 (95% confidence limits: 0.51–0.93), indicating substantial agreement. While agreement was substantial, side-to-side differences were not reflected equally when peak and mean force methods of assessing CMJ asymmetry were used. These methods should not be used interchangeably, but rather a combined approach should be used where practitioners consider both peak and mean force to obtain the fullest picture of athlete asymmetry.  相似文献   
565.
This article describes a ‘Mastery Rubric’ (MR) used to design both the curriculum and the assessments in a new two‐year certificate programme intended to train physicians in clinical research skills. The MR for clinical research skills is built around a set of core research skills: critical review of literature; articulation of research objective; development of research design; development of analysis plan; implementation of the study; implementation of the analysis plan and presentation of results. Four distinct levels of performance are described for each skill: beginning, novice, competent and proficient. This rubric outlines and provides a path to mastery of the clinical research skills the certificate programme was designed and funded to target. Using the rubric to design the curriculum ensures that courses will provide instruction in key domains, promotes assessment that demonstrates development in the target skills and knowledge, and encourages reflection and cognitive self‐monitoring in the students. It is a flexible, criterion‐referenced definition of ‘success’ for students as well as the programme itself. The criteria are characterised in terms of the skills, habits of mind and organisational principles that can foster excellence in clinical research, but the approach can be generalised.  相似文献   
566.
Previous looking time studies have shown that infants use the heads of cat and dog images to form category representations for these animal classes. The present research used an eye-tracking procedure to determine the time course of attention to the head and whether it reflects a preexisting bias or online learning. Six- to 7-month-olds were familiarized with cats or dogs in upright or inverted orientations and then tested with a novel cat and novel dog in the same orientation. In the upright orientation, infants fixated head over body throughout familiarization; with inversion, no head preference was observed. These findings suggest that infant reliance on the head to categorize cats versus dogs results from a bias that pushes attention to the head.  相似文献   
567.
Experimentation with substances is typical for many young people, but unfortunately some will go on to develop substance abuse problems that substantially affect their lives. Successfully intervening with students who use or abuse substances is a challenge for school mental health professionals across the nation. There is a need for evidence‐based practices that school professionals can use when working with students who have substance abuse problems. This article provides school professionals in secondary settings with current information on student substance use rates, evidence‐based individual and group interventions, and discussion of the 42 Code of Federal Regulations, Part 2 (42 CFR). © 2008 Wiley Periodicals, Inc.  相似文献   
568.
Schools play a privileged and strategic role in the lives of children acting as their principle environment away from home. Additionally, schools act as part of the community linking families and neighborhoods. These characteristics make schools a relevant setting for mental health service delivery and support to children and parents. In this article the role of the school environment on the development of childhood depression and as a leverage point in the prevention and treatment of depression will be discussed. Rationales for this viewpoint, as well as practical suggestions for reducing the deleterious effects of schooling on children's emotional well‐being, are offered. © 2009 Wiley Periodicals, Inc.  相似文献   
569.
The purpose of this study was to develop and validate a self-report instrument that can be used to measure learning in the cognitive, affective, and psychomotor domains. The study underwent three phases, each with its own data collection and analysis. Phase I featured the development, testing, and factor analysis of an 80-item instrument that addressed cognitive, affective, and psychomotor learning that was administered to a sample of 142 online and face-to-face learners. Based on the results, the instrument was reduced to 21 items for Phase II and tested with a new sample of 171 online and face-to-face students. The results of confirmatory factor analysis suggested a better data fit with an even smaller 9-item instrument, which was then administered to a new sample of 221 online and face-to-face students in Phase III. The results of this final phase are presented along with the resulting CAP Perceived Learning Scale, a 9-item self-report measure of perceived cognitive, affective, and psychomotor learning. Implications and usage of the CAP Perceived Learning Scale for research and practice are also discussed.  相似文献   
570.
Hydrogen(H2)is a clean energy carrier with enormous potential to support deep decarbonization towards net-zero and a circular carbon economy.However,H2 producti...  相似文献   
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