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1.
In this article we examine the complex relationship between care experience, mental health and exclusion from school and how young people (YP) negotiate these different experiences and identities. The study is a secondary analysis, informed by symbolic interactionist theory, of interviews conducted with 19 care experienced YP in Scotland. Not all of the YP were excluded and not all had a formal mental health diagnosis, as such our study design allows interrogation of the contexts and relationships which not only facilitate but also disrupt pathways to exclusion. It also allows reconsideration of assumptions of vulnerability which are often applied to care experienced YP. Our findings suggest that these YP are moving beyond ‘role playing’ the identities ascribed to them and actively seek out relationships which enable them to construct alternative identities.  相似文献   
2.
ABSTRACT

Participation in youth sport is positively associated with physical fitness and performance. The purpose of the current study was to examine if physical fitness measures during childhood and early adolescence predicted high school sport participation. Participants included youth in the Michigan State University Motor Performance Study. Measures consisted of the endurance shuttle run, Wells sit-and-reach, jump and reach, standing long jump, agility shuttle run and 30-yard dash. Individual, generalized estimating equation models were used to estimate the association between each measure and the odds of participating in high school sport. For both sexes, the endurance shuttle run and agility shuttle run were related to sport participation. For boys only, the long jump and 30-yard dash were also associated with sport participation. Better physical fitness and performance across several dimensions in childhood, including those related to motor skills, enhanced the likelihood of sport participation in high school.  相似文献   
3.
ABSTRACT

Two studies were employed to test the reliability and validity of the Swimming Competence Questionnaire (SCQ) among primary school children. Study 1 was a cross-sectional survey in 4959 primary school children. Study 2 was a pre-post-test quasi-experiment among 1609 primary school children who underwent a 20-lesson learn-to-swim programme. In Study 1, exploratory structural equation modelling revealed excellent goodness-of-fit and scale reliability for a two-factor model comprising distance and skill factors, which supported the construct and convergent validity. SCQ scores were significantly and positively correlated with swimming outcomes (i.e., self-efficacy, intention, swimming frequency), which supported SCQ’s concurrent and criterion validity. Average variance extracted for the SCQ factors exceeded cut-off criteria supporting discriminant validity. In Study 2, pre-test SCQ scores correlated significantly and positively with the SCQ scores, self-efficacy, intention, and swimming frequency at post-test, which supported SCQ’s test-retest reliability and predictive validity. Positive intraclass correlation between SCQ scores and coach ratings at post-test provided evidence for SCQ’s inter-rater reliability. SCQ scores significantly improved at post-test, which supported SCQ’s ecological validity. In conclusion, findings indicate that the SCQ is a valid and reliable measure to assess primary school children’s swimming competence, in terms of swimming distance and basic water survival skills.  相似文献   
4.
The purpose of this study was to identify which averaging methods most accurately measures peak cardiorespiratory fitness (CRF) parameters [peak O2 uptake (VO2), peak O2pulse and peak respiratory exchange ratio (RER)] in a sample of healthy children and adolescents. In this cross-sectional multicenter study, we recruited 278 healthy children aged 12–17 years. We compared the mean peak value of three CRF parameters using the recommended averaging methods (30-second block average) with alternative averaging methods such as moving averages or shorter smoothing periods. We also assessed averaging methods for accuracy by individually reviewing breath-by-breath scatter plots. The 30-second block average method resulted in a lower mean peak VO2 and in an increased proportion of underestimated peak values. Using a 30-second moving average significantly increased mean peak values which increased accuracy. Similar results were found for peak RER and peak O2pulse. In conclusion, the currently recommended averaging method (30-second block average) increased the risk of misinterpretation of peak CRF values in children. Using a moving average approach decreased misinterpretation and increased accuracy.  相似文献   
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6.
Although there has been a great deal of research into Collaborative Information Retrieval (CIR) and Collaborative Information Seeking (CIS), the majority has assumed that team members have the same level of unrestricted access to underlying information. However, observations from different domains (e.g. healthcare, business, etc.) have suggested that collaboration sometimes involves people with differing levels of access to underlying information. This type of scenario has been referred to as Multi-Level Collaborative Information Retrieval (MLCIR). To the best of our knowledge, no studies have been conducted to investigate the effect of awareness, an existing CIR/CIS concept, on MLCIR. To address this gap in current knowledge, we conducted two separate user studies using a total of 5 different collaborative search interfaces and 3 information access scenarios. A number of Information Retrieval (IR), CIS and CIR evaluation metrics, as well as questionnaires were used to compare the interfaces. Design interviews were also conducted after evaluations to obtain qualitative feedback from participants. Results suggested that query properties such as time spent on query, query popularity and query effectiveness could allow users to obtain information about team's search performance and implicitly suggest better queries without disclosing sensitive data. Besides, having access to a history of intersecting viewed, relevant and bookmarked documents could provide similar positive effect as query properties. Also, it was found that being able to easily identify different team members and their actions is important for users in MLCIR. Based on our findings, we provide important design recommendations to help develop new CIR and MLCIR interfaces.  相似文献   
7.
This paper considers two paradigms of process-aware information systems (PAIS) that are used to share knowledge about planning and executing tasks. The case-based task management (CBTM) system is based on the transduction of execution protocols, so-called cases; and the pattern-based task management (PBTM) system is based on task patterns that are derived from cases but yield more abstract information. As user motivation to contribute to a collaborative task management system is a crucial factor for its success, we consider the different motivational requirements of CBTM and PBTM from a psychological point of view. Based on experimental findings about different factors that have been shown to enhance people's motivation to contribute their knowledge to a shared pool, we compare the two approaches and assess which one is more appropriate with respect to motivation.  相似文献   
8.
Tree-structured vector quantization (VQ) is a technique designed to represent a codebook that simplifies encoding as well as vector quantizer design. Most design algorithms for tree-structured VQ used in the past are based on heuristics that successively partition the input space. Recently, Chou, Lookabaugh and Gray proposed a tree-pruning heuristic in which a given initial tree is pruned backwards according to certain optimization criterion. We define the notion of an optimal pruned tree subject to a cost constraint and study the computational complexity of finding such an optimal tree for various cost functions. Under the assumption that all trees are equally probable, we show that, on the average, the number of pruned trees in a given tree is exponential in the number of leaves. Furthermore, we prove that finding an optimal pruned tree subject to constraints such as entropy or the expected-depth is NP-hard. However, we show that when the constraint is the number of leaves, the problem can be solved in polynomial time. We develop an algorithm to find the optimal pruned tree in O(nk) time, where n is the size of the initial tree and kis the constraint size.  相似文献   
9.
As the costs of certain types of scientific research have escalated and as growth rates in overall national science budgets have declined, so the need for an explicit science policy has grown more urgent. In order to establish priorities between research groups competing for scarce funds, one of the most important pieces of information needed by science policy-makers is an assessment of those groups' recent scientific performance. This paper suggests a method for evaluating that performance.After reviewing the literature on scientific assessment, we argue that, while there are no simple measures of the contributions to scientific knowledge made by scientists, there are a number of ‘partial indicators’ — that is, variables determined partly by the magnitude of the particular contributions, and partly by ‘other factors’. If the partial indicators are to yield reliable results, then the influence of these ‘other factors’ must be minimised. This is the aim of the method of ‘converging partial indicators’ proposed in this paper. We argue that the method overcomes many of the problems encountered in previous work on scientific assessment by incorporating the following elements: (1) the indicators are applied to research groups rather than individual scientists; (2) the indicators based on citations are seen as reflecting the impact, rather than the quality or importance, of the research work; (3) a range of indicators are employed, each of which focusses on different aspects of a group's performance; (4) the indicators are applied to matched groups, comparing ‘like’ with ‘like’ as far as possible; (5) because of the imperfect or partial nature of the indicators, only in those cases where they yield convergent results can it be assumed that the influence of the ‘other factors’ has been kept relatively small (i.e. the matching of the groups has been largely successful), and that the indicators therefore provide a reasonably reliable estimate of the contribution to scientific progress made by different research groups.In an empirical study of four radio astronomy observatories, the method of converging partial indicators is tested, and several of the indicators (publications per researcher, citations per paper, numbers of highly cited papers, and peer evaluation) are found to give fairly consistent results. The results are of relevance to two questions: (a) can basic research be assessed? (b) more specifically, can significant differences in the research performance of radio astronomy centres be identified? We would maintain that the evidence presented in this paper is sufficient to justify a positive answer to both these questions, and hence to show that the method of converging partial indicators can yield information useful to science policy-makers.  相似文献   
10.
As an introduction to the special issue on “emerging nanotechnologies”, this paper puts in perspective contemporary debates and challenges about nanotechnology. It presents an overview of diverse analyses and expectations about this presumably revolutionary set of technological, scientific and industrial developments. Three main lines of argument can then be delineated: first of all, the degree of cumulativeness of science and technologies and the respective roles of newcomers and incumbents in the industrial dynamics; second the knowledge dynamics in nanotechnologies, especially the linkages by science and technology and third the role of institutions (network, geographic agglomeration and job market). It finally discusses methodologies to delineate the field of nanotechnologies and to collect data.  相似文献   
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