Does exercise have a protective effect on cognitive function under hypoxia? A systematic review with meta-analysis

ObjectiveThis study aimed to examine (1) the independent effects of hypoxia on cognitive function and (2) the effects of exercise on cognition while under hypoxia.MethodsDesign: Systematic review with meta-analysis. Data sources: PubMed, Scopus, Web of Science, PsychInfo, and SPORTDiscus were searched. Eligibility criteria for selecting studies: randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered (Aim 2), as were studies investigating the effects of hypoxia on cognition (Aim 1).ResultsIn total, 18 studies met our inclusionary criteria for the systematic review, and 12 studies were meta-analyzed. Exposure to hypoxia impaired attentional ability (standardized mean difference (SMD) = –0.4), executive function (SMD = –0.18), and memory function (SMD = –0.26), but not information processing (SMD = 0.27). Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement (SMD = 0.3, 95% confidence interval: 0.14 – 0.45, I² = 54%, p < 0.001). Various characteristics (e.g., age, cognitive task type, exercise type, exercise intensity, training type, and hypoxia level) moderated the effects of hypoxia and exercise on cognitive function.ConclusionExercise during exposure to hypoxia improves cognitive function. This association appears to be moderated by individual and exercise/hypoxia-related characteristics.     

Shape-oriented storage and retrieval of geometric figures and chromosome images

Four advantages of storing and retrieving geometric figures and chromosome images through the use of shape-oriented similarity measures are presented. A complemented but not distributive lattice and a distributive but not complemented lattice are found. Answers to triangle related fuzzy queries such as “retrieve the triangles which are very similar to isosceles triangles but not similar to a given triangle Δx”, and chromosome related fuzzy queries such as “retrieve the chromosomes which are more or less similar to median chromosomes and very very similar to a given chromosome A” are presented and illustrated by examples. For shape-oriented storage of triangles, it is proposed to store the angles of each triangle in decreasing order of the magnitude and logically order all the triangles according to the magnitude of the angles. For shape-oriented storage of chromosomes, it is proposed to logically order all the chromosomes individually and independently according to the angular sums of its exterior biangles and interior biangles. The results may have useful applications in information storage and retrieval, artificial intelligence and pattern recognition.     

Contemporary education policies in Southeast Asia: common philosophical underpinnings and practices

This article examines the various education policies in Southeast Asian countries, highlighting the underlining philosophies and current practices in the region. The conceptual framework of the presentation includes key concepts such as access and equity, unity and identity, quality and relevance, efficiency and effectiveness. Each of these key concepts will be analysed using a framework consisting of key questions, guiding philosophies, policy options as well as issues and challenges. The article reviews policies relating to questions such as “who get access to what kinds of education?”, “how to widen access?”, “how to ensure success?”, “what kinds of education for a multicultural society?”, “how to promote national integration and social cohesion through education?”, “how to improve quality of education?”, “how to manage and administer the school delivery system?”. It draws examples from different countries in the SEA region to illustrate the issues and challenges in formulating and implementing contemporary education policies.     

Traversing the Challenges of Conducting Research with Young, Immigrant Children: The Case of Korean Children

Based on a qualitative study on young Korean immigrant children’s interpretation of American popular culture, this paper reflects on the researchers’ role by examining the research challenges faced. Prior to discussing the research obstacles in conducting the study, we begin with briefly describing its methodology and design. Next, we discuss the various obstacles we encountered when conducting our study and howwe attempted to overcome these dilemmas by discussing two major struggles during the research process: a) the relationships between the researchers and our young participants, and b) the cultural sensitivity that was needed in initially gaining permission from and working with the parents of our informants. It then illuminates how the researchers attempted to cope with such difficulties by rethinking a researchers’s role emphasizing the importance of cultural context in research. Finally, the paper provides some discussions and implications based on our research experiences.     

A Habermasian Approach to Critical Reading

This article explores the connection between critical reading and Jurgen Habermas’s theory of communicative action. It proposes that Habermas’s criteria used for evaluating validity claims in communicative action can be applied in reading texts critically. Analyses of different types of texts are presented to show how critical reading is done in a Habermasian way. This article ends with a discussion of the application of Habermas’s theory in addressing educational issues.     

IRT Approaches to Modeling Scores on Mixed-Format Tests

This article considers psychometric properties of composite raw scores and transformed scale scores on mixed-format tests that consist of a mixture of multiple-choice and free-response items. Test scores on several mixed-format tests are evaluated with respect to conditional and overall standard errors of measurement, score reliability, and classification consistency and accuracy under three item response theory (IRT) frameworks: unidimensional IRT (UIRT), simple structure multidimensional IRT (SS-MIRT), and bifactor multidimensional IRT (BF-MIRT) models. Illustrative examples are presented using data from three mixed-format exams with various levels of format effects. In general, the two MIRT models produced similar results, while the UIRT model resulted in consistently lower estimates of reliability and classification consistency/accuracy indices compared to the MIRT models.     

Mathematics Achievement of Children in China and the United States

First and fifth graders in Beijing and Chicago were given a battery of mathematics test. Whether tested with problems requiring solely computation or with ones requiring application of knowledge about mathematics, American children's performance was consistently inferior to that of Chinese children. Interviews with American children suggested that they like mathematics, believe they are doing well in mathematics, and do not perceive mathematics as a difficult subject. American children's poor performance appears to be attributable, in part, to low motivation for devoting more attention to mathematics. Low standards held by American parents for academic achievement and lower interest in teaching mathematics by American teachers appear to contribute to American children's poor performance.     

Cognitive skills and literacy performance of Chinese adolescents with and without dyslexia

The present study sought to identify cognitive abilities that might distinguish Hong Kong Chinese adolescents with dyslexia and to assess how these abilities were associated with Chinese word reading, word dictation, and reading comprehension. The cognitive skills of interest were morphological awareness, visual-orthographic knowledge, rapid naming, and verbal working memory. A total of 90 junior secondary school students, 30 dyslexic, 30 chronological age controls, and 30 reading level controls was tested on a range of cognitive and literacy tasks. Dyslexic students were less competent than the control students in all cognitive and literacy measures. The regression analyses also showed that verbal working memory, rapid naming, morphological awareness, and visual-orthographic knowledge were significantly associated with literacy performance. Findings underscore the importance of these cognitive skills for Chinese literacy acquisition. Overall, this study highlights the persistent difficulties of Chinese dyslexic adolescents who seem to have multiple causes for reading and spelling difficulties.