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The development of peak performances is a main research focus in sports science. It is unclear how many former top junior athletes achieve success in the elite class later. The aim of the present study was to examine the careers of athletes who participated in major junior or adult/elite cycling events using prospective and retrospective analysis of competition results. The official results of major junior (age < or = 18 years) and elite (age > 18 years) cycling races from 1980 to 2004 were analysed. Age-related aspects, career lengths, and success were compared between riders who presented results in both junior and elite races (JUNIOR ELITE) and riders who had no junior race results (ELITE ONLY). Altogether, 27,454 results of 8004 athletes from 108 countries were collected. We found that 29.4% of the elite athletes had participated in junior World Championships, and that 34% of the participants in junior World Championships later participated in major elite competitions. JUNIOR ELITE athletes are significantly more successful in several cycling disciplines and have their first and last elite result at a younger age than ELITE ONLY athletes. No difference was found in career lengths. The data presented here emphasize the importance of long-term training programmes in the development of peak performance in cycling.  相似文献   
3.
Around 1960, the politics of the emerging media society in Sweden tended to fixate the formative functions of mass communication. The monopoly of public service broadcast media, press subsidies and new tendencies in film policy were some of the issues around which uncertainty prevailed. New methods to provide reliable data were sought by politicians, since empirical facts were required as arguments for an updated media policy. This article examines the different ways that the field of media studies was introduced in Sweden between 1960 and 1980. We argue that Swedish academic media studies departed from, and emerged within, a rather diffuse borderland between industry, politics and academia. The formation of national media research in Sweden can partly be seen as an effect of politicians and the media industry wanting to be better informed on issues such as media influence, media ownership and the habits and composition of the media audience.  相似文献   
4.
The purpose of this study is to find a theoretically grounded, practically applicable and useful granularity level of an algorithmically constructed publication-level classification of research publications (ACPLC). The level addressed is the level of research topics. The methodology we propose uses synthesis papers and their reference articles to construct a baseline classification. A dataset of about 31 million publications, and their mutual citations relations, is used to obtain several ACPLCs of different granularity. Each ACPLC is compared to the baseline classification and the best performing ACPLC is identified. The results of two case studies show that the topics of the cases are closely associated with different classes of the identified ACPLC, and that these classes tend to treat only one topic. Further, the class size variation is moderate, and only a small proportion of the publications belong to very small classes. For these reasons, we conclude that the proposed methodology is suitable to determine the topic granularity level of an ACPLC and that the ACPLC identified by this methodology is useful for bibliometric analyses.  相似文献   
5.
Abstract

This article explores the case of the videodisc in the context of the progress of technological innovation in the field of education. It looks at what the medium has to offer and the ways in which it is currently being used, before going on to consider the factors that may impede its acceptance and what can be done towards ensuring its implementation.  相似文献   
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In recent years, many established concepts in the theory of human motor development have undergone profound change, and our knowledge has increased greatly. Nevertheless, some outstanding problems remain unsolved. A central problem concerns the redundancy of effective movements, first pointed out by N. A. Bernstein. The human motor system is mechanically complex and can make use of large number of degrees of freedom. The controlled operation of such a system requires a reduction of mechanical redundancy, effectively by reducing the number of degrees of freedom. More recent work has shown that this problem is hard to solve explicitly by computing solutions to the equations of motion of the system. Equally challenging to traditional computational approaches is the fact the motor systems show remarkable adaptability and flexibility in the presence of changing biomechanical properties of motor organs during development and when faced with different environmental conditions or tasks. Solutions to these problems would have a large impact on a variety of issues in child development. In this article, we stress the importance of the somatic selection of neuronal groups in maps for the progressive transformation of a primary movement repertoire into a set of motor synergies and adaptive action patterns. We present results from computer simulations of a simple motor system that works according to such selectional principles. This approach suggests a provisional solution to Bernstein's problem and provides new parameters to guide experimental approaches to the development of sensorimotor coordination.  相似文献   
7.
Tertiary Education and Management - Performance indicators and performance-based funding are becoming integral components of higher education (HE) policy around the globe. We explore some of the...  相似文献   
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The Bologna Process of higher education reform has led to a vast array of different programs of study in German teacher training. In this article, we firstly analyze the implementation of Bachelor programs in teacher training, comparing profession-oriented programs (i.e. those aiming to train students for the teaching profession from the beginning of studies) to polyvalent programs (i.e. those aiming at broad qualifications and including a late decision to become a teacher). Secondly, we investigate whether students enrolled in these study programs differ systematically in their subjective certainty about their career choice. To answer these questions, we analyze portfolios of documents related to teacher training programs from nine German universities that prepare students for teaching in the academic track. Additionally, we analyze data from N?=?2585 Bachelor and N?=?928 Master degree students. We found that most programs, even when they espouse polyvalence, require an early decision to become a teacher. Moreover, our data confirm findings from earlier studies indicating that student teachers are highly certain about their career choice from the very beginning, with students in polyvalent programs being slightly less certain than those in profession-oriented programs (d?=?0.32).  相似文献   
9.
Research on the patterns of international student mobility and the dynamics shaping these patterns has been dominated by studies reflecting a Western orientation, discourse, and understanding. Considering political, economic, cultural, historical, and ecological factors, this study argues that international student mobility is not only an issue of the economically developed, politically stable, and academically advanced Western world but also one that involves countries with different economic, political, and academic characteristics. Taking into account various theoretical orientations, this study argues that political, economic, cultural, and historical factors have led to the emergence of non-traditional destinations for international students; these countries are labeled as emergent regional hubs. In order to empirically test this, a social network analysis was conducted on a worldwide dataset representing 229 countries. The findings evidenced the strong position of traditional destinations for international students. However, the results also suggest the rise of several regional hubs, which are undergoing internationalization processes in different forms and with different rationales. The mobility patterns in emerging regional hubs deviate from those in traditional destinations, which fundamentally change the nature of internationalization in this context.  相似文献   
10.
Known as the ‘third polar region’, the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment.  相似文献   
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