Associations of total sedentary time,screen time and non-screen sedentary time with adiposity and physical fitness in youth: the mediating effect of physical activity

The aims of the present study were: i) to examine the associations of total accelerometer-based sedentary time (ST) and specific-domain self-reported ST (i.e., screen-based, educational-based, social-based, and other-based ST) with adiposity and physical fitness in youth; and ii) to analyse the mediation effect of physical activity (PA) on associations.

This study was conducted with 415 children (9.1 ± 0.4 years) and 853 adolescents (13.6 ± 1.6 years) in Spain during 2011–2012. Total ST and PA were assessed by accelerometry. Leisure-time spent in twelve sedentary behaviours was self-reported. Adiposity and physical fitness was measured following the ALPHA battery for youth.

Total accelerometer-based ST was positively associated with global adiposity score in children, and negatively associated with global physical fitness score in children and adolescents; but relationships were not independent of PA. PA mediated all associations of accelerometer-based and self-reported ST with adiposity or physical fitness in children. Conversely, screen-, educational-, social-, and other-based ST were negatively related to physical fitness in adolescents, independently of PA.

These findings give an impetus to developing effective strategies for specifically promoting PA in children and for increasing PA while reducing ST in adolescents in order to produce improvements on adiposity and physical fitness.     

Accreditation in Hong Kong and international peer review

Increasingly, student outcomes assessment is being viewed as a component of comprehensive academic program review. The Hong Kong peer review process is typical of program review in the United Kingdom and Europe. In the second article in this issue, Ruth Green describes a typical U.S. program review process. —Editor.     

Correction to: Mechanisms mediating the relation between reading self-concept and reading comprehension

European Journal of Psychology of Education - The article Mechanisms mediating the relation between reading self-concept and reading comprehension, written by Franziska Maria Locher, Sarah Becker,...     

Digital Archival Image Collections: Who Are the Users?

Archival digital image collections are a relatively new phenomenon in college library archives. Digitizing archival image collections may make them accessible to users worldwide. There has been no study to explore whether collections on the Internet lead to users who are beyond the institution or a comparison of users to a national or international audience. This study of the Orang Asli Archive, a repository for anthropological, historical, journalistic, and other documentary sources relevant to Orang Asli peoples and cultures of Malaysia, examines the Web analytics of its digital archival image collections.     

Avoiding and Correcting Bias in Score-Based Latent Variable Regression With Discrete Manifest Items

This article considers models involving a single structural equation with latent explanatory and/or latent dependent variables where discrete items are used to measure the latent variables. Our primary focus is the use of scores as proxies for the latent variables and carrying out ordinary least squares (OLS) regression on such scores to estimate parameters in the structural equation. We are concerned with the bias in these OLS estimates; we present two approaches to deal with this bias. Extending the work of Skrondal and Laake (2001) Skrondal, A. and Laake, P. 2001. Regression among factor scores. Psychometrika, 66: 563–576. [Crossref], [Web of Science ®] , [Google Scholar] on continuous items, we derive sufficient conditions under which the use of scores based on item response theory leads to unbiased OLS estimates at the population level; we deem this approach “bias avoiding.” We also consider Croon's (2002) Croon, M. 2002. “Using predicted latent scores in general latent structure models”. In Latent variable and latent structure models, Edited by: Marcoulides, G. A. and Moustaki, I. 195–223. Mahwah, NJ: Lawrence Erlbaum Associates, Inc.  [Google Scholar] bias correction methodology for continuous items and explore its efficacy on discrete items; we deem this approach “bias correcting.” We illustrate the performance of the 2 approaches through numerical examples of large simulated data sets.     

Integrating direct and inquiry-based instruction in the teaching of critical thinking: an intervention study

Critical thinking is a unifying goal of modern education. While past research has mostly examined the efficacy of a single instructional approach to teaching critical thinking, recent literature has begun discussing mixed teaching approaches. The present study examines three modes of instruction, featuring the direct instruction approach and the inquiry-based approach in different sequences and proportions, in enhancing Chinese secondary student’s critical thinking performance. A total of 651 Grade 12 students participated in an 18-hour intervention with pre- and post-intervention measures on critical thinking performance and critical thinking dispositions. Specifically, critical thinking assessments utilizing different response format were used. Those who received training showed greater improvement on at least one of the critical thinking assessments compared to those who received no training. Participants’ performances with regards to different critical thinking assessments are discussed. Benefits of adopting more than one instructional approach to teaching critical thinking are highlighted.     

A Teaching–Learning Sequence for the Special Relativity Theory at High School Level Historically and Epistemologically Contextualized

This paper discusses some topics that stem from recent contributions made by the History, the Philosophy, and the Didactics of Science. We consider these topics relevant to the introduction of the Special Relativity Theory (SRT) in high school within a contextualized approach. We offer an outline of a teaching?Clearning sequence dealing with the SRT within this frame of reference. Such a sequence was tried out on a group of high school students in Argentina. The results obtained seem to indicate that the proposal has been effective as regards the motivational aspects and the understanding students gained of some of its concepts.     

Addressing institutional potential loss of records and knowledge in Africa: The case of the ECA institutional repository – A knowledge base on African socio-economic development

In its 50 years of existence, the United Nations Economic Commission of Africa (UNECA) has created and holds a vast quantity of information and knowledge in a variety of formats, including printed and electronic. These represent the corporate memory, providing historical evidence of its actions and decisions. The information resources include published materials such as flagship publications, journal articles, conference proceedings, technical reports, mission reports, annual reports, working papers, policy briefs, speeches and other grey literature, all which outline important research or decisions that have been made on the economic and social development in Africa. In 2009 the Library was awarded seed funding to implement the ECA Institutional Repository (IR). This paper discusses the various activities that have been undertaken to realize the project including; highly customized Dspace installation to support the MARC21 metadata, digitization, migration of metadata from the Library Integrated Management System (HORIZON) and, customization of the Dspace workflow to enable review of imported records. The paper also highlights lessons learnt, challenges and some of the best practices developed throughout the implementation and roll out of the ECA IR project. The Institutional Repository at http://repository.uneca.org/ is the first of its kind within the United Nations Secretariat and offers unique knowledge and information not available elsewhere pertaining to regional programmes, decisions and resolutions promoting social and economic development of Africa.     

Perceptual completion in newborn human infants

Despite decades of studies of human infants, a still open question concerns the role of visual experience in the development of the ability to perceive complete shapes over partial occlusion. Previous studies show that newborns fail to manifest this ability, either because they lack the visual experience required for perceptual completion or because they fail to detect the pattern of motion. To distinguish these possibilities, newborns' perception of a center-occluded object was tested, using stroboscopic motion. Infants (mean age of 72 hr) perceived the object as a connected unit, providing the first evidence that the newborn is capable of filling in gaps in the visible surface layout when the relevant visual information can be detected by his or her immature visual system.