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21.
Teachers' conception and use of the terms “learning disability” and “emotional disturbance” was investigated in two studies to determine the implications for developing educational programs. In Study I, experienced teachers in a special education certification program categorized 106 child characteristics as LD, ED, or both LD and ED. In Study II, in-service teachers specified annual achievement goals and extent of regular class placement for the same child bearing either the LD or ED label. Results from Study I showed that the majority of child characteristics were considered by teachers to be relevant to either LD or ED labels. A subset of 23 characteristics was significantly related to one or the other label—LD characteristics representing academic and health/development areas, and ED characteristics representing psychological and behavioral areas. In Study II, teachers recalled the ED label significantly more often than the LD label, but did not specify significantly different goals or regular class participation for the child under the two labeling conditions. The findings support the conclusion that teachers can treat the LD and ED constructs as mutually exclusive when eligibility for special service is the decision, and as mutually inclusive when program-planning decisions are made.  相似文献   
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Abstract

The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.  相似文献   
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ABSTRACT

Purpose: Most built environment studies have quantified characteristics of the areas around participants’ homes. However, the environmental exposures for physical activity (PA) are spatially dynamic rather than static. Thus, merged accelerometer and global positioning system (GPS) data were utilized to estimate associations between the built environment and PA among adults. Methods: Participants (N = 142) were recruited on trails in Massachusetts and wore an accelerometer and GPS unit for 1–4 days. Two binary outcomes were created: moderate-to-vigorous PA (MVPA vs. light PA-to-sedentary); and light-to-vigorous PA (LVPA vs. sedentary). Five built environment variables were created within 50-meter buffers around GPS points: population density, street density, land use mix (LUM), greenness, and walkability index. Generalized linear mixed models were fit to examine associations between environmental variables and both outcomes, adjusting for demographic covariates. Results: Overall, in the fully adjusted models, greenness was positively associated with MVPA and LVPA (odds ratios [ORs] = 1.15, 95% confidence interval [CI] = 1.03, 1.30 and 1.25, 95% CI = 1.12, 1.41, respectively). In contrast, street density and LUM were negatively associated with MVPA (ORs = 0.69, 95% CI = 0.67, 0.71 and 0.87, 95% CI = 0.78, 0.97, respectively) and LVPA (ORs = 0.79, 95% CI = 0.77, 0.81 and 0.81, 95% CI = 0.74, 0.90, respectively). Negative associations of population density and walkability with both outcomes reached statistical significance, yet the effect sizes were small. Conclusions: Concurrent monitoring of activity with accelerometers and GPS units allowed us to investigate relationships between objectively measured built environment around GPS points and minute-by-minute PA. Negative relationships between street density and LUM and PA contrast evidence from most built environment studies in adults. However, direct comparisons should be made with caution since most previous studies have focused on spatially fixed buffers around home locations, rather than the precise locations where PA occurs.  相似文献   
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Altmetrics have been proposed as a way to assess the societal impact of research. Although altmetrics are already in use as impact or attention metrics in different contexts, it is still not clear whether they really capture or reflect societal impact. This study is based on altmetrics, citation counts, research output and case study data from the UK Research Excellence Framework (REF), and peers’ REF assessments of research output and societal impact. We investigated the convergent validity of altmetrics by using two REF datasets: publications submitted as research output (PRO) to the REF and publications referenced in case studies (PCS). Case studies, which are intended to demonstrate societal impact, should cite the most relevant research papers. We used the MHq’ indicator for assessing impact – an indicator which has been introduced for count data with many zeros. The results of the first part of the analysis show that news media as well as mentions on Facebook, in blogs, in Wikipedia, and in policy-related documents have higher MHq’ values for PCS than for PRO. Thus, the altmetric indicators seem to have convergent validity for these data. In the second part of the analysis, altmetrics have been correlated with REF reviewers’ average scores on PCS. The negative or close to zero correlations question the convergent validity of altmetrics in that context. We suggest that they may capture a different aspect of societal impact (which can be called unknown attention) to that seen by reviewers (who are interested in the causal link between research and action in society).  相似文献   
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The Artist Initiative at the San Francisco Museum of Modern Art (SFMOMA) is piloting models for increased collaboration between conservators and curators through joint work with artists. We seek a more integrated, holistic approach to the care and research of our collection. The project, funded by the Andrew W. Mellon Foundation, comprises five robust research engagements that serve the curatorial collecting departments of the museum (Photography, Painting and Sculpture, Media Art, and Architecture and Design). Three of the projects are monographic studies, examining the work of Ellsworth Kelly, Vija Celmins, and Julia Scher in depth, while two more are thematic, exploring modes of displaying digitally-driven design objects, and developing strategies for addressing the problem of color shift common to photographic prints made with experimental materials during the 1970s and 1980s. The Artist Initiative is also charged with developing hybrid working spaces to advance collaborative approaches to collections research at the museum's new downtown campus and at SFMOMA's new Collections Center in South San Francisco. These spaces include the Collections Workroom, a 56?sq?m (600?sq?ft) space that functions as a studio for visiting artists, a conservation laboratory, an interview suite, and a classroom at SFMOMA's downtown campus. At the Collections Center, a 121?sq?m (1300?sq?ft) Mock-Up Gallery has been built as a working model of one of the museum's new galleries. A functional exhibition space, the Mock-Up Gallery is also a venue for interviewing artists, prototyping exhibition formats, and meeting with students, scholars, museum staff, and community members. With the goal of contributing to critical discourses in contemporary art history, art conservation, and public engagement, each of the Artist Initiative projects includes a colloquium that will bring experts from multiple fields together with the featured artists. Thereafter we aim to share our findings widely through public programs and a range of publications, both digitally and in print.  相似文献   
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The aims of this study were to compare the aerobic energy cost of four 'on-snow' skating techniques in cross-country skiing and to examine the relationships between performance and aerobic energy cost. Twelve male skiers from recreational to national standard performed four level skating trials of 6 min duration in random order, each at the same submaximal velocity but with a different skating technique: (1) 'offset' (V1), using a double asymmetrical and asynchronous pole plant as weight is transferred to one ski; (2) 'two-skate' (V2A), where the pole plant is symmetrical; (3) 'one-skate' (V2), where there is a pole plant as weight is transferred to each ski; and (4) 'conventional', without poles. Oxygen uptake (VO2), pulmonary ventilation, the respiratory exchange ratio and heart rate were measured using a K4(b2) portable gas analyser. The aerobic energy cost (VO2/mean speed) and heart rate were higher (P < 0.05) in the one-skate than in the offset condition. This may be explained by the greater and more efficient use of the upper body and the lower variation in centre of gravity velocity in the offset condition. The aerobic energy cost was 5-9% higher (P < 0.01) in the conventional than in the other techniques, probably because of the shorter duration of propulsive forces within a cycle in the conventional skating condition. Moreover, in ski skating, the mechanical efficiency (propulsive forces/total forces) was shown to be higher in the upper than in the lower limbs. The correlation coefficient between performance and aerobic energy cost was significant in the two-skate (r = 0.68, P = 0.02), one-skate (r = 0.72, P = 0.01) and conventional (r = 0.62, P = 0.04) conditions, but not in the offset condition (r = 0.50, P = 0.10). Our results stress the importance of the upper body component in cross-country skiing and that the aerobic energy cost discriminates between skiers of different standards.  相似文献   
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