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41.
Benoît Godin 《Research Policy》2004,33(8):1217-1229
High technology is a concept much in vogue in OECD countries, for it is a symbol of an “advanced” economy. This paper looks at why and how the concept and its indicator acquired such fame. It explains that the reason has to do with the fact that the indicator emerged in the context of debates on the competitiveness of countries and their efforts to maintain or improve their positions in world trade. The first part looks at the early statistics behind the indicator (R&D/sales), statistics developed in official analyses of industrial R&D surveys before the 1950s. The second part traces the evolution of the R&D/sales ratio in the 1960s through its use as an indicator of research or technological intensity. The third part discusses the internationalization of the indicator via the OECD.  相似文献   
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The purpose of this study was to validate and cross-validate the Beunen-Malina-Freitas method for non-invasive prediction of adult height in girls. A sample of 420 girls aged 10-15 years from the Madeira Growth Study were measured at yearly intervals and then 8 years later. Anthropometric dimensions (lengths, breadths, circumferences, and skinfolds) were measured; skeletal age was assessed using the Tanner-Whitehouse 3 method and menarcheal status (present or absent) was recorded. Adult height was measured and predicted using stepwise, forward, and maximum R (2) regression techniques. Multiple correlations, mean differences, standard errors of prediction, and error boundaries were calculated. A sample of the Leuven Longitudinal Twin Study was used to cross-validate the regressions. Age-specific coefficients of determination (R (2)) between predicted and measured adult height varied between 0.57 and 0.96, while standard errors of prediction varied between 1.1 and 3.9 cm. The cross-validation confirmed the validity of the Beunen-Malina-Freitas method in girls aged 12-15 years, but at lower ages the cross-validation was less consistent. We conclude that the Beunen-Malina-Freitas method is valid for the prediction of adult height in girls aged 12-15 years. It is applicable to European populations or populations of European ancestry.  相似文献   
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The faculty and administration of a school of education in the mid-Atlantic region formally adopted a standards-based, conceptual framework that reflects the values articulated by the faculty and the outcomes for students as they prepare for and develop in their professions. Faculty and administrators agreed to use the framework as the basis for examining professional programs, academic courses, and professional experiences, as well as for governing interactions with one another as colleagues. This article describes the conceptual framework, its goals, research used to evaluate the framework, and the outcomes attained.  相似文献   
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In this study, we examined the impact of a new academic mentoring program aimed at preventing student dropout in math, science and technology. The MIRES program entails bimonthly meetings between students entering college and university students completing their undergraduate degree in science and engineering. A randomized pretest-posttest control group design was used to evaluate the program’s short-term impact. At the end of the program, mentees (n = 150) presented significantly higher levels of motivation, a more positive career decision profile and enhanced institutional attachment and social adjustment than students in the control group (n = 157). MIRES mentees also showed success and persistence rates (mainly male participants) that were significantly higher than those of students in the control group.  相似文献   
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Longitudinal studies provide unique opportunities but are also faced with several limitations. The purpose of this study was to document three of these issues ("imperfect" design, evolution of data collection methods, representativeness) by means of the Leuven Longitudinal Study on Lifestyle, Fitness and Health (LLSLFH). The LLSLFH (1969 - 2004) comprises observations on males between 12 and 18 years and at 30, 35, 40, and 47 years, and on females at 16 and 40 years. In the most recent phase of the study, spouses and offspring were also included. The different phases and evolving research questions throughout the LLSLFH required an appropriate adaptation of the research design. The associated evolution of data collection methods largely reflects the changing ideas about physical fitness, body composition, and physical activity, the continuing search for new and better measurement techniques, and the need for adaptations with age. Ongoing study participants are representative in terms of body composition and, except for adolescence in males, also physical activity. No straightforward answer can be given concerning physical fitness. In both sexes, socio-economic status is above average. When informed about the possible "pitfalls" of longitudinal research in advance, several measures could be taken to prevent or limit them as much as possible.  相似文献   
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