Pedometer reliability, validity and daily activity targets among 10- to 15-year-old boys

The aims of this study were to: (1) determine whether the number of pedometer counts recorded by adolescents differs according to the adiposity of the participant or location on the body; (2) assess the accuracy and reliability of pedometers during field activity; and (3) set adolescent pedometer-based physical activity targets. Seventy-eight 11- to 15-year-old Boy Scouts completed three types of activity: walking, fast walking and running. Each type was performed twice. Participants wore three pedometers and one activity monitor during all activities. Participants were divided into groups of normal weight (BMI < 85th percentile) and at risk of being overweight (BMI > or = 85th percentile). Intra-class correlations across the three activities indicated reliability (r = 0.51 - 0.92, P < 0.001). This conclusion was supported by narrow limits of agreement that were within a pre-set range that was practically meaningful. Multivariate analysis of covariance indicated adiposity group differences, but this difference was a function of the increased stature among the larger participants (P < 0.001). Ordinary least-squares regression models and multi-level regression models showed positive associations between the number of pedometer and activity monitor counts recorded by the three groups of participants during all activities (all P < 0.001). The mean number of counts recorded for all participants during the fast walk was 127 counts per minute. In conclusion, the pedometers provided an accurate assessment of adolescent physical activity, and a conservative estimate of 8000 pedometer counts in 60 min is equivalent to 60 min of moderate to vigorous physical activity.     

Alterations in autonomic cardiac modulation in response to normobaric hypoxia

Purpose: The present study aimed to determine if autonomic cardiac modulation was influenced by acute exposure to normobaric hypoxia. Method: Ten healthy male lowland dwellers completed five block-randomised single-blinded, crossed-over acute exposures to a normobaric hypoxic environment, each separated by 24 hours’ recovery (20.3%, 17.4%, 14.5%, 12.0% and 9.8% F_IO₂). Supine recordings were made of arterial oxygen saturation and electrocardiogram (ECG). RR intervals from the ECG trace were analysed for time (SDNN, lnrMSSD), frequency (lnVLF, lnLF, lnHF, lnTP, LFnu, and HFnu), and nonlinear (DFA-α1 and SampEn) heart rate variability components. Results: A significant reduction in arterial SaO₂ occurred with reduced F_IO₂, along with a rise in heart rate (Cohen’s d?=?1.16, 95% Confidence Interval [2.64–6.46]), significant at 9.8% F_IO₂. A decrease in autonomic cardiac modulation was also found as shown by a statistically significant (at 9.8% F_IO₂) decrease in lnTP (d?=?1.84 [1.74–1.94]), and SampEn (d?=?0.98 [0.83–1.12]) and an increase in DFA-α₁ (d?=?0.72 [0.60–0.84]) from normoxia at 9.8% F_IO₂. Conclusion: The decrease in variability indicated a reduction in autonomic cardiac modulation. There appears to be a threshold ～9.8% F_IO₂ (～6000?m equiv.), below which significant alterations in autonomic control occur.     

Comparison of three web-scale discovery services for health sciences research

Objective

The purpose of this study was to investigate the relative effectiveness of three web-scale discovery (WSD) tools in answering health sciences search queries.

Methods

Simple keyword searches, based on topics from six health sciences disciplines, were run at multiple real-world implementations of EBSCO Discovery Service (EDS), Ex Libris''s Primo, and ProQuest''s Summon. Each WSD tool was evaluated in its ability to retrieve relevant results and in its coverage of MEDLINE content.

Results

All WSD tools returned between 50%–60% relevant results. Primo returned a higher number of duplicate results than the other 2 WSD products. Summon results were more relevant when search terms were automatically mapped to controlled vocabulary. EDS indexed the largest number of MEDLINE citations, followed closely by Summon. Additionally, keyword searches in all 3 WSD tools retrieved relevant material that was not found with precision (Medical Subject Headings) searches in MEDLINE.

Conclusions

None of the 3 WSD products studied was overwhelmingly more effective in returning relevant results. While difficult to place the figure of 50%–60% relevance in context, it implies a strong likelihood that the average user would be able to find satisfactory sources on the first page of search results using a rudimentary keyword search. The discovery of additional relevant material beyond that retrieved from MEDLINE indicates WSD tools'' value as a supplement to traditional resources for health sciences researchers.     

Teacher Efficacy Research 1998–2009: Signs of Progress or Unfulfilled Promise?

This review investigates the state of teacher self- and collective efficacy research conducted from 1998 to 2009. Two hundred and eighteen empirical articles published in 1998–2009 were examined for key characteristics and compared to research published in the previous 12 years (i.e., 1986–1997). Results from the review show increases in overall teacher efficacy research, methodological diversity, domain specificity, internationalization, and focus on collective efficacy. Continuing problem areas were a lack of attention to the sources of teacher efficacy, continued measurement and conceptual problems, a lack of evidence for the links between teacher efficacy and student outcomes, and uncertain relevance of teacher efficacy research to educational practice. An outline of directions for future teacher efficacy research is provided.     

A Study of Teacher Candidates’ Experiences Investigating Global Climate Change Within an Elementary Science Methods Course

We investigated the inclusion of a curricular module on global climate change in an Elementary Science Methods course. Using complementary research methods, we analyzed findings from 63 teacher candidates’ drawings, questionnaires, and journal entries collected throughout their participation in the module. We highlighted three focal cases to illustrate the diversity of participants’ experiences. Findings suggest potential positive impacts on teacher candidates’ content understanding related to global climate change, confidence to teach, and awareness of resources to support their future science instruction. Recommendations for science teacher education underscore the importance of providing opportunities for teacher candidates to increase their relevant content understanding, helping teacher candidates become familiar with appropriate curricular resources, and engaging in ongoing conversation and evaluation of developing views and understandings related to global climate change.     

Impact of a content and methods course sequence on prospective secondary mathematics teachers’ beliefs

In this article, we report on a study of beliefs about mathematics, teaching, and proof conducted with six prospective secondary mathematics teachers as they completed a two-semester sequence of a content course and a methods course. The initial beliefs of the participants were identified using interview and survey data, and potential shifts in beliefs were examined through further interview and survey data combined with classroom observations and written work. While their beliefs about mathematics and proof appeared to be relatively stable, their beliefs about teaching shifted from a more teacher-centered view to beliefs that foreground the activities and understandings of the students. These shifts are analyzed using the construct of belief structures, and activities and events from the courses that may have facilitated the shifts are identified. The results are consistent with the literature in some respects, such as the stability of the participants’ beliefs about mathematics. On the other hand, our results present new information about how prospective secondary mathematics teachers’ beliefs about teaching may be impacted.     

Considerations for designing practice for deaf readers

Low reading comprehension persists among deaf readers, and recent research indicates that low automaticity in recognizing words and parsing sentence patterns is a significant source of the difficulty. When a learner does manage to gain an insight about some aspect of printed English, there may be limited impact on comprehension until the new knowledge can be applied fluently because the multiple cognitive demands of reading call for completing basic linguistic operations with a minimum of conscious effort. The research literature agrees that the route to improved automaticity is effective practice, and, thus, practice is also a likely route to increased comprehension. This article presents considerations to guide the design of practice for deaf readers. Certain of these notions are relatively applied in nature and may shape practice activities directly, for example, the discussion of research-based guidelines for tailoring the sequence and composition of practice items. Other parts of the discussion, such as those related to word recognition, are more theoretical than directive, and they imply research hypotheses that can and should be tested empirically. A principal point of this article is that without appreciable improvements in practice, the reading of many deaf students will remain largely unimproved.     

Science literacy and academic identity formulation

The purpose of this article is to report findings from an ethnographic study that focused on the co‐development of science literacy and academic identity formulation within a third‐grade classroom. Our theoretical framework draws from sociocultural theory and studies of scientific literacy. Through analysis of classroom discourse, we identified opportunities afforded students to learn specific scientific knowledge and practices during a series of science investigations. The results of this study suggest that the collective practice of the scientific conversations and activities that took place within this classroom enabled students to engage in the construction of communal science knowledge through multiple textual forms. By examining the ways in which students contributed to the construction of scientific understanding, and then by examining their performances within and across events, we present evidence of the co‐development of students' academic identities and scientific literacy. Students' communication and participation in science during the investigations enabled them to learn the structure of the discipline by identifying and engaging in scientific activities. The intersection of academic identities with the development of scientific literacy provides a basis for considering specific ways to achieve scientific literacy for all students. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 1111–1144, 2004     

Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs

In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children.