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1.
ABSTRACT

The aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time.  相似文献   
2.
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published.  相似文献   
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The article sets off with a brief summary of the history of appraisal and disposal of records as processed at the National Archives of Iceland (NAI) since its establishment in 1882 to present times. Rules on appraisal and disposal of records introduced in 1900, 1911, and 1916 were ignored and all records were kept. Status quo remained until 1985 when a new National Archives Act was passed. The appraisal and disposal process adopted then is described and explained. It included the publication of instructions on records management as well as forms relating to records management. The influence of acts of law on the appraisal and disposal process is explained. Finally the experience with the arrangement of organised appraisal in Iceland is described.  相似文献   
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In South Africa the education system for black children is fraught with problems. These problems are the direct result of apartheid and have been compounded by poverty and illiteracy. In this article the problem of poorly qualified or unqualified teachers is discussed especially with regard to the teaching of map skills to children in their fifth school year. The project team needed to develop affordable materials which could be used in large classes by teachers after a very short period of training. Books and other materials which are available commercially were examined, but for various reasons were found to be unsuitable for local conditions. After determining the extent of the problem, the project team followed a grassroots process of developing a flip chart which teachers learnt to use with confidence and which enabled pupils to master the concepts and skills necessary for understanding a map.  相似文献   
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The validity and reliability of curriculum‐based measures in reading as indicators of performance and progress for secondary‐school students were examined. Thirty‐five grade 8 students completed reading aloud and maze‐selection measures weekly for 10 weeks. Criterion measures were the state standards test in reading and the Woodcock–Johnson III Test of Achievement. Different time frames for each measure were compared. Most alternate‐form reliability coefficients were above .80. Criterion‐related validity coefficients ranged from .77 to .89. No differences related to time were found. Only maze selection reflected significant growth, with an average increase of 1.29 correct choices per week. Maze growth was related to the reading performance level and to change on the Woodcock–Johnson III from pre‐ to posttest.  相似文献   
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The paper deals with studies of engineering programmes in foreign languages at Vilnius Technical University (VTU), Lithuania. In order to organize studies in foreign languages, an International Studies Centre was established in 1992. The following aims were pursued: integrating into the systems of university education of European countries and promoting international exchange of students and staff. BSc studies (architecture, civil engineering, mechanical engineering and electronic engineering programmes) are organized in English, French and German. Over 150 undergraduate students from Lithuania and foreign countries are studying at the centre. About 150 students are enrolled for the next academic year.  相似文献   
10.
With the plethora of health sites on the Internet, it is sometimes hard to know where to start. This is a basic list of health sites that either cover a subject area comprehensively, or are good general sites to lead to more specific information. Most of these sites include both full-text information as well as links to many other sites on the World-Wide Web. Included are medical, nursing, dental, alternative health, consumer health, organization, and government sites.  相似文献   
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