Does modality matter? A latent profile and transition analysis of sedentary behaviours among school-aged youth: The UP&DOWN study     

David Sánchez-Oliva  Rebecca M. Leech  Alberto Grao-Cruces  Irene Esteban-Cornejo  Carmen Padilla-Moledo  Oscar L. Veiga 《Journal of sports sciences》2020,38(9):1062-1069

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   

The role of task and ego-oriented climate in explaining students’ bright and dark motivational experiences in Physical Education     

Luis García-González  Javier Sevil-Serrano  Angel Abós  Nathalie Aelterman  Leen Haerens 《Physical Education & Sport Pedagogy》2019,24(4):344-358

Background: A distinction is made in Achievement Goal Theory (AGT) between task-oriented (i.e. effort, intra-individual progress, and self-comparison) and ego-oriented (i.e. inter-individual progress and normative comparison) climates. Combining insights from AGT and Self-Determination Theory (SDT), studies in the PE context have shown that a task-oriented climate positively relates to need satisfaction, although the findings regarding the motivating role of an ego-oriented climate are inconsistent. Moreover, little is known about the role of task- or ego-oriented climates in explaining experiences of basic psychological need frustration.

Purpose: Grounded in AGT and SDT, the aim of the present study was to examine if experiences of basic psychological need satisfaction and need frustration can explain why task- and ego-oriented climates elicit positive and negative motivational outcomes in PE, respectively.

Research design: Cross-sectional study.

Method: A sample of 524 secondary school students (51.1% boys, M_age?=?14.51; SD?=?1.81) from five different secondary schools participated in this study. Students reported on their perceptions of task- and ego-oriented climates, motivational regulations, basic psychological need satisfaction, and need frustration, as well as positive and negative outcomes in PE. Structural equation modeling was used to investigate our objective.

Results: We found that a task-oriented climate had a strong and positive relationship with basic psychological need satisfaction, eliciting a bright pathway to autonomous motivation and affective attitude. An ego-oriented climate was positively related to basic psychological need frustration, eliciting a dark pathway to amotivation and boredom. A negative cross-path from task-oriented climate to basic psychological need frustration was also found, while no significant cross-paths were found from ego-oriented climate to basic psychological need satisfaction.

Conclusions: This study provides a better understanding of the mechanisms that explain why task- and ego-oriented climates shape students’ motivational experiences in PE lessons. It is suggested that a task-oriented climate elicits a bright pathway towards more optimal functioning, because it fosters experiences of need satisfaction and buffers against experiences of need frustration. In contrast, an ego-oriented climate is primarily positively related to feelings of need frustration and negative motivational outcomes. Practical implications for PE teacher training are discussed.  相似文献   

Effect of different loading conditions on running mechanics at different velocities     

Germán Carretero-Navarro  Doménico Cherubini  Wolfgang Taube 《European Journal of Sport Science》2019,19(5):595-602

Weighted vests are widely used to improve running economy and performance. However, it is not well-studied how running mechanics are adapted to counteract the higher peak vertical ground reaction forces (Fpeak) while running with such a device. Therefore, the present study aimed to investigate the effects of different loading conditions on running mechanics at different velocities. Thirteen subjects participated in two separate sessions one week apart. In the first session, maximal aerobic speed (MAS) was determined through a maximal incremental running test while in the second session, they were instructed to run during one minute under different loading (0%, +10% and +20% of body mass [BM]) and velocity (60%, 80% and 100% of MAS) conditions in a random order. Spatiotemporal data were recorded and then running mechanics modelled using the spring-mass model. The main results indicated that vertical and leg stiffness (Kvert and Kleg, respectively) were increased (P?P?>?.05) when load was changed. At the same time, alterations of the running kinematics were observed such as longer contact times, reduced flight times, stride frequencies and step lengths, as well as an increase of the centre of mass dynamics. Based on these results it is assumed that runners maintain a certain stiffness level for each velocity despite different loading conditions. As a consequence, Fpeak increases and this probably causes spatiotemporal adjustments in the movement kinematics.  相似文献   

Quality flaw prediction in Spanish Wikipedia: A case of study with verifiability flaws     

Edgardo Ferretti  Leticia Cagnina  Viviana Paiz  Sebastián Delle Donne  Rodrigo Zacagnini  Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181

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   

TAM and stages of adoption of blended learning in higher education by application of data mining techniques     

Antonio Víctor Martín-García  Fernando Martínez-Abad  David Reyes-González 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(5):2484-2500

  相似文献   

Digital Module 05: Diagnostic Measurement—The G‐DINA Framework https://ncme.elevate.commpartners.com     

Wenchao Ma  Jimmy de la Torre 《Educational Measurement》2019,38(2):114-115

In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback.  相似文献   

论军队院校图书馆数字化特色馆藏建设     

马祥林 《中国图书馆学报》2003,29(6)

建设军队院校图书馆数字化馆藏要处理好在线获得与非在线获得、特色数据库与特色数字馆藏、信息组织中《中图法》与军事学科体系、军事信息与其他信息的关系。实行联采、统编、分藏是解决军队院校图书馆数字化特色馆藏问题的有效方法。参考文献4。  相似文献   

论超文本技术在分类法编制中的应用   总被引：11，自引：0，他引：11  

马张华  李玲 《大学图书馆学报》2001,19(1):60-62,66

超文本是检索语言编制和维护理想的技术支持手段。使用超文本技术 ,可以改进分类体系中主题之间多维关系的揭示、从多个角度组织信息资源、进行轮排、设置镜像类目、动态组织分类体系以及联结不同的检索系统、联结说明与规则系统等。同时 ,应注意从超文本结构的角度重新审视原有的关于知识组织的理论、方法 ;探讨新技术方法的使用特点和规律 ;研究分类结构中整体控制问题  相似文献   

多媒体在武术难度动作创新中的实用性研究     

马云慧  张天祥 《搏击·武术科学》2005,2(9):38-39

运用多媒体技术辅助教练员和运动员创编竞技武术套路高质量难新动作,辅助运动员加快完成目标动作的定型过程,对创新难度动作在训练中出现的问题进行及时的目标反馈、重构和完善,提高了创编的效率,减少了运动员在创新难度动作的探索阶段中不必要的损伤。  相似文献   

论李清照的诗人形象     

汪燕霞  马月霞 《河北广播电视大学学报》2005,10(6):41-44

李清照是我国宋代著名女词人，以婉约派词家著称于世。她不仅精于填词，而且工诗善文。在她为数不多的诗作中，风格豪放，雄浑悲壮，折射出爱国主义精神的熠熠光彩，并由此展现出李清照的诗人形象：少年成名，才气纵横，锋芒毕露而不知稍加掩敛；身为女子，而有丈夫气，指点江山，激扬文字；成就斐然，却又有自知，勇于自我解剖，敢于素面朝天。  相似文献