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71.
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In many Western science systems, funding structures increasingly stimulate academic research to contribute to practical applications, but at the same time the rise of bibliometric performance assessments have strengthened the pressure on academics to conduct excellent basic research that can be published in scholarly literature. We analyze the interplay between these two developments in a set of three case studies of fields of chemistry in the Netherlands. First, we describe how the conditions under which academic chemists work have changed since 1975. Second, we investigate whether practical applications have become a source of credibility for individual researchers. Indeed, this turns out to be the case in catalysis, where connecting with industrial applications helps in many steps of the credibility cycle. Practical applications yield much less credibility in environmental chemistry, where application-oriented research agendas help to acquire funding, but not to publish prestigious papers or to earn peer recognition. In biochemistry practical applications hardly help in gaining credibility, as this field is still strongly oriented at fundamental questions. The differences between the fields can be explained by the presence or absence of powerful upstream end-users, who can afford to invest in academic research with promising long term benefits.  相似文献   
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Twenty-four children with conduct disorders were familiarized with a pattern-matching task, and their self-efficacy expectations for this task were assessed. Subjects were then given either “Success” or “Failure” feedback for a series of similar problems, and their self-efficacy was reassessed. Finally, task persistence was evaluated by allowing subjects to attempt as many additional pattern-matching problems as they wished, with all subjects receiving failure feedback. Results indicated that, although the two groups of subjects were initially similar, the success group's self-efficacy was significantly higher following feedback. The success group also attempted significantly more problems while later receiving failure feedback, and there was a significant positive correlation between task persistence and the second self-efficacy rating. These findings were related to Bandura's self-efficacy theory and to educational programming for conduct-disordered children.  相似文献   
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根据《棋经十三篇》这一部棋书,通过分析,看到了《棋经》与《孙子》的关系甚为密切,它不仅从篇章款式上摹拟《孙子十三篇》,而更是从有关棋的战略战术等内容问题上与《孙子十三篇》相吻合。因此。棋道如兵法。棋理合乎一般事物之辩证法则。  相似文献   
77.
Book Reviews     
This study examined the teaching of games via a tactical approach (also known as teaching games for understanding) from the theoretical perspective of social constructivism. A pilot study (of student teachers (STs) and pupils) informed the ‘main’ study which included collecting data on 49 STs, 58 cooperating teachers (CTs) and 1177 pupils. ST data were collected through videotaping (lessons), interviews and questionnaires; CT data through interviews and questionnaires; and pupil data through questionnaires. Data analysis techniques included systematic coding of teaching behaviours through computer software, using constant comparison to code open-ended question responses, and computing frequencies of Likert-scale question responses. T-tests were used to compare pre- and post-CT workshop data. Findings suggest that STs’ teaching of the tactical approach was in line with a social constructivist perspective, in part because lessons were student-centred. Overall student activity was 53% of all lessons taught, and STs facilitated pupil learning through several question and answer scenarios. Pupils wrote that they enjoyed playing games in what amounted to ‘authentic’ settings. Their responses also suggest that learning took place through ‘legitimate peripheral participation in communities of practice’ and this facilitated pupil movement through the ‘zone of proximal development’. There were indications that pupil experiences were mediated by ST competence. CTs reported that an in-service workshop on the tactical approach and mentoring was beneficial and subsequent pairings with STs elicited positive feelings from both parties.  相似文献   
78.
Background:Little is known about exercise cardiac power(ECP),defined as the ratio of directly measured maximal oxygen uptake with peak systolic blood pressure during exercise,on heart failure(HF)risk.We examined the association of ECP and the risk of HF.Methods:This was a population-based cohort study of 2351 men from eastern Finland.The average time to follow-up was 25 years.Participants participated at baseline in an exercise stress test.A total of 313 cases of HF occurred.Results:Men with low ECP(<9.84 mL/mmHg,the lowest quartile)had a 2.37-fold(95%confidence interval(95%CI):1.68-3.35,p<0.0001)hazards ratio of HF as compared with men with high ECP(>13.92 mL/mmHg,the highest quartile),after adjusting for age.Low ECP was associated with a 1.96-fold risk(95%CI:1.38-2.78,p<0.001)of HF after additional adjustment for conventional risk factors.After further adjustment for left ventricular hypertrophy,the results hardly changed(hazards ratio=1.87,95%CI:1.31-2.66,p<0.001).One SD increase in ECP(3.16 mL/mmHg)was associated with a decreased risk of HF by 28%(95%CI:17%-37%).Conclusion:ECP provides a noninvasive and easily available measure from cardiopulmonary exercise tests in predicting HF.However,ECP did not provide additional value over maximal oxygen uptake.  相似文献   
79.
基于专利引文分析的时间线技术   总被引:3,自引:0,他引:3  
在对专利引文可视化技术现状进行分析的基础上,将基于引文分析的时间线技术运用到专利文献的可视化分析。详细阐述该技术的理论依据、设计思想,并用美国专利数据库中的DVD激光头专利进行技术应用,证明该技术能揭示专利文献中的技术热点及其发展演变,并挖掘关键技术。  相似文献   
80.
The speed at which a player can swing a bat is central to the games of baseball and softball, determining, to a large extent, the hit speed of the ball. Experimental and analytical studies of bat swing speed were conducted with particular emphasis on the influence of bat moment of inertia on swing speed. Two distinct sets of experiments measured the swing speed of colege baseball and fast-pitch softball players using weighted rods and modified bats. The swing targets included flexible targets, balls on a tee and machine pitched balls. Internal mass alterations provided a range of inertial properties. The average measured speeds, from 22 to 31 m s−1, are consistent with previous studies. Bat speed approximately correlates with the moment of inertia of the bat about a vertical axis of rotation through the batter's body, the speed generally decreasing as this moment of inertia increases. The analytical model assumes pure rotation of the batter/bat system about a vertical axis through the batter's body. Aerodynamic drag of the batter's arms and the bat is included in the model. The independent variable is bat moment of inertia about the rotation axis. There is reasonable agreement between the model and the measured speeds. Detailed differences between the two suggest the importance of additional degrees of freedom in determining swing speed.  相似文献   
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