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931.
ABSTRACT

This study assessed the intra-individual reliability of oxygen saturation in intercostal muscles (SmO2-m.intercostales) during an incremental maximal treadmill exercise by using portable NIRS devices in a test-retest study. Fifteen marathon runners (age, 24.9 ± 2.0 years; body mass index, 21.6 ± 2.3 kg·m?2; V?O2-peak, 63.7 ± 5.9 mL·kg?1·min?1) were tested on two separate days, with a 7-day interval between the two measurements. Oxygen consumption (V?O2) was assessed using the breath-by-breath method during the V?O2-test, while SmO2 was determined using a portable commercial device, based in the near-infrared spectroscopy (NIRS) principle. The minute ventilation (VE), respiratory rate (RR), and tidal volume (Vt) were also monitored during the cardiopulmonary exercise test. For the SmO2-m.intercostales, the intraclass correlation coefficient (ICC) at rest, first (VT1) and second ventilatory (VT2) thresholds, and maximal stages were 0.90, 0.84, 0.92, and 0.93, respectively; the confidence intervals ranged from ?10.8% – +9.5% to ?15.3% – +12.5%. The reliability was good at low intensity (rest and VT1) and excellent at high intensity (VT2 and max). The Spearman correlation test revealed (p ≤ 0.001) an inverse association of SmO2-m.intercostales with V?O2 (ρ = ?0.64), VE (ρ = ?0.73), RR (ρ = ?0.70), and Vt (ρ = ?0.63). The relationship with the ventilatory variables showed that increased breathing effort during exercise could be registered adequately using a NIRS portable device.  相似文献   
932.
This study extends prior research on approaches to teaching and perceptions of the teaching situation by investigating these elements when e-learning is involved. In this study, approaches to teaching ranged from a focus on the teacher and the taught content to a focus on the student and their learning, resembling those reported in previous investigations. Approaches to e-teaching ranged from a focus on information transmission to a focus on communication and collaboration. An analysis of perceptions of the teaching situation in relation to e-learning identified key themes influencing adopted approaches: control of teaching, institutional strategy, pedagogical and technological support, time required, teacher skills for using e-learning, and student abilities and willingness for using learning technology. Associations between these elements showed three groups of teachers: one focusing on transmission of information teaching both face-to-face and online while having a general negative perception of the teaching situation in relation to e-learning; a second focusing on student learning both face-to-face and online while having a general positive perception; and a third presenting unexpected patterns of associations. These results may be helpful for supporting different groups of teachers in employing e-learning in their on-campus units of study. At the same time, further research is proposed for inquiring into specific approaches in different disciplines and different university contexts.  相似文献   
933.
This study investigates the development of proportional and additive methods along primary and secondary school. In particular, it simultaneously investigates the use of additive methods in proportional word problems and the use of proportional methods in additive word problems. We have also studied the role played by integer and non-integer relationships between the given numbers and the nature of quantities (discrete or continuous) in the development of these phenomena. A test consisting of additive and proportional missing-value word problems was solved by 755 primary and secondary school students (from fourth to tenth grade). The findings indicate that the use of additive methods in proportional situations increased during primary school and decreased during secondary school, whereas the use of proportional methods in additive situations increased along primary and secondary school. Moreover, the presence or absence of integer ratios strongly affects this behavior, but the nature of quantities only has a small influence on the use of proportional methods.  相似文献   
934.
The role of student attention for predicting kindergarten word reading was investigated among 432 students. Using Strengths and Weaknesses of ADHD Symptoms and Normal Behavior Rating Scale behavior rating scores, the authors conducted an exploratory factor analysis, which yielded three distinct factors that reflected selective attention. In this study, the authors focused on the role of one of these factors, which they labeled attention-memory, for predicting reading performance. Teacher ratings of attention-memory predicted word reading above and beyond the contribution of phonological awareness and vocabulary knowledge. In addition, the relations between four teacher practices and attention ratings for predicting reading performance were examined. Using hierarchical linear modeling, the authors found significant interactions between student attention and teacher practices observed during literacy instruction. In general, as ratings of attention improved, better kindergarten word reading performance was associated with high levels of classroom behavior management. However, better word reading performance was not associated with high levels of teacher task orienting. A significant three-way interaction was also found among attention, individualized instruction, and teacher task redirections. The role of regulating kindergarten student attention to support beginning word reading skill development is discussed.  相似文献   
935.
High schools throughout the United States experience problems with violence, drugs, and crime. School administrators have responded with policies and strategies designed to prevent school violence such as zero tolerance approaches, partnerships with law enforcement agencies, security camera installations, and hiring additional security personnel to monitor students. The purpose of this research is to determine how Chicanas/os and school officials perceive and experience these techniques as part of a broader process of criminalization. In addition, using qualitative data we explore perceptions of safety and experiences with victimization. Qualitative data include interviews (with high school students, school administrators, and security personnel), an evaluation of a Chicana/o-centered program, and participant observations in a predominantly Chicana/o high school located in the Southwest. Findings show some students find the new techniques to be invasive and hostile and others find school security measures as providing a sense of security; and administrators and teachers generally find value in the new approaches. From a LatCrit perspective, we argue that Chicana/o and Mexicana/o experiences are set within a context of racialized space where criminalization is one possible outcome of school security measures.  相似文献   
936.
The participation of Spain in the European Higher Education Area (EHEA) involves a number of important challenges for academics. Adapting to an educational model that is characterised by competence-based teaching is a difficult task, yet it is of paramount importance in the context of current reforms. In an educational system in which the traditional lecture prevails, learning-centred teaching represents a major cultural change with significant consequences. The objective of this study is to offer economics lecturers some practical techniques for use in the classroom. Specifically, it includes suggestions for the planning, preparation and teaching of lectures, seminars, tutorials, case studies, debates, and computer-based learning. It also provides practical advice on student assessment.  相似文献   
937.
Research on masculinity has become an important area of gender and education that includes a wide range of empirical concerns and theoretical approaches. This article identifies a number of studies that are asking questions about the conceptual usefulness of masculinity within educational contexts. The first section explores how educational researchers are beginning to suggest alternative ways that hegemonic masculinity may be configured. The second section draws upon work that interrogates the disconnection of gender from sex. Such work considers the importance of understanding schooling worlds through an untethering of gender categories from physical bodies. The third section suggests the possibility of a post-masculinity position by exploring research that questions the viability of masculinity as a conceptual frame to understand gender. In conclusion, the paper argues that such developments can be used heuristically to inform the critical reflexiveness of future research in the area.  相似文献   
938.
Cross-linguistic studies suggest that the orthographic system determines the reading performance of dyslexic children. In opaque orthographies, the fundamental feature of developmental dyslexia is difficulty in reading accuracy, whereas slower reading speed is more common in transparent orthographies. The aim of the current study was to examine the extent to which different variables of words affect reaction times and articulation times in developmental dyslexics. A group of 19 developmental dyslexics of different ages and an age-matched group of 19 children without reading disabilities completed a word naming task. The children were asked to read 100 nouns that differed in length, frequency, age of acquisition, imageability, and orthographic neighborhood. The stimuli were presented on a laptop computer, and the responses were recorded using DMDX software. We conducted analyses of mixed-effects models to determine which variables influenced reading times in dyslexic children. We found that word naming skills in dyslexic children are affected predominantly by length, while in non-dyslexics children the principal variable is the age of acquisition, a lexical variable. These findings suggest that Spanish-speaking developmental dyslexics use a sublexical procedure for reading words, which is reflected in slower speed when reading long words. In contrast, normal children use a lexical strategy, which is frequently observed in readers of opaque languages.  相似文献   
939.
Abstract

Cooperating teachers are often identified as some of the most important figures in the preparation of new teachers, and the reasons are not difficult to understand. Surprisingly, however, very little research has been conducted to quantify the effects of cooperating teachers on student teachers. This study examines the impact of student teachers' perceived interactions with their cooperating teachers and the influence that interaction has on student teachers' self‐efficacy for teaching. Results indicate a moderate correlation between perceptions of teaching efficacy and cooperating teacher‐student teacher interactions. Differences were found in the frequency of interaction based on the certification level of the student teacher, with elementary level student teachers perceiving a greater amount of interaction with their cooperating teachers. However, no differences based on certification level were detected in perceived efficacy. Student teachers' perceptions of the level of guidance offered by their cooperating teachers provided the most reliable predictor for their efficacy belief.  相似文献   
940.
This article analyzes the concept of idealization in chemistry and the role played by pure substance and laboratory product. This topic has evident repercussions in the educational contexts that are applied to the science classroom, which are highlighted throughout the text. A common structure for knowledge construction is proposed for both physics and chemistry with particular emphasis on the relations between two of the levels: the ideal level and the quasi-ideal level. The ideal level is crucial for operations related to theoretical constructions and explanations, whereas the quasi-ideal level is of special importance in the verification of propositions. In chemistry, the ideal level and the quasi-ideal level include the entities, pure substance and laboratory product, respectively. This article provides an in-depth discussion of the concept of pure substance, an idealized entity whose empirical correlate is laboratory product. The study of the link between the two is a very significant part of the problem of the relations between theory and reality in chemistry. These entities are used to analyze and interpret different situations and contexts in research as well as teaching. The article concludes by using classroom examples to illustrate the didactic implications of the issues addressed.  相似文献   
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