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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prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove).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 paintings by Canaletto (1697–1768), made with the help of a camera obscura, are just like real photographs, documenting as they do the Venice of the XVIII century with an accurate reproduction of all the details. The brown–green front left by the Laminaria, an alga living between the high and low tide, constitutes a precise biological indication of the average level of the high tide. By comparing the level of this front at Canaletto’s time with the present level, we can calculate/discover the relative sea level rise which has occurred in the last two and a half centuries.  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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To increase its visibility among the general public and the international scientific community, the Croatian Medical Journal (CMJ), a small journal from the so‐called scientific periphery, introduced a media strategy of sending press releases to journalists and email notices to the newsdesk of a high‐profile international scientific journal. Subsequent news coverage and the positive response of journalists show that press releases and targeted email notices increased international visibility of articles published in a small scientific journal, and improved communication with journalists as mediators of scientific information to the general public.  相似文献   
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The technical study of wall paintings from the Buddhist temple complex at Nako, Western Himalayas, was one of the basic preconditions required for designing an appropriate conservation strategy. The complex, composed of four temples from the eleventh–twelfth century, offered a unique possibility to carry out a comprehensive research of technology and painting materials used in early and later western Tibetan Buddhist wall paintings as well as a comparative assessment with murals from other sites in the Western Himalayas. The study was based on extensive fieldwork and an integrated analytical approach comprising a wide range of non-destructive and micro-destructive methods. Answering the question of the coevality of paintings in the smaller temples with other original murals, the precise characterisation of binding media, the detection of the yellow dye gamboge and natural minerals posnjakite and brochantite identified for the first time in Himalayan murals, the clarification of technology of metal decoration, and the making of raised elements are some of the most exciting results which emerged from the research.  相似文献   
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