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Traditional approaches to formative evaluation include one-to-one trials which provide some information about revisions that are needed in instructional materials, but typically fail to provide sufficient information about the learner's cognitive processing problems while studying the materials. Read-think-aloud methods are a viable alternative to traditional one-to-ones and provide valuable information about the learner's cognitive processing while reading instructional text. In this paper we describe the read-think-aloud method of formative evaluation and offer suggestions for its use.  相似文献   
74.
A kindergarten class of 9 boys and 11 girls took the 1986 Stanford-Binet Intelligence Scale (Fourth Edition) and the Wechsler Preschool and Primary Scale of Intelligence. Of 6 correlations of total scores and subtest pairs, only the correlation of total scores was statistically significant (p<.01).  相似文献   
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Exercise testing on motorised treadmills provides valuable information about running performance and metabolism; however, the impact of treadmill type on these tests has not been investigated. This study compared the energy demand of running on two laboratory treadmills: an HP Cosmos (C) and a Quinton (Q) model, with the latter having a 4.5 times stiffer running platform. Twelve experienced runners ran identical bouts on these treadmills at a range of four submaximal velocities (reported data is for the velocity that approximated 75–81% VO2max). The stiffer treadmill elicited higher oxygen consumption (C: 46.7 ± 3.8; Q: 50.1 ± 4.3 ml·kg?1 · min?1), energy expenditure (C: 16.0 ± 2.5; Q: 17.7 ± 2.9 kcal · min?1), carbohydrate oxidation (C: 9.6 ± 3.1; Q: 13.0 ± 3.9 kcal · min?1), heart rate (C: 155 ± 16; Q: 163 ± 16 beats · min?1) and rating of perceived exertion (C: 13.8 ± 1.2; Q: 14.7 ± 1.2), but lower fat oxidation (C: 6.4 ± 2.3; Q: 4.6 ± 2.5 kcal · min?1) (all analysis of variance treadmill comparisons < 0.01). This study confirms that caution is required when comparing performance and metabolic results between different treadmills and suggests that treadmills will vary in their comparability to over-ground running depending on the running platform stiffness.  相似文献   
77.
The aim of this study was to determine if the hypoxaemic stimulus generated by intense exercise results in the physiological response of increased erythropoietin production. Twenty athletes exercised for 3 min at 109 +/- 2.8% (mean +/- s) maximal oxygen consumption. Estimated oxyhaemoglobin saturation was measured by reflective probe pulse oximetry (Nellcor N200) and was validated against arterial oxyhaemoglobin saturation by CO-oximetry in eight athletes. Serum erythropoietin concentrations-as measured using the INCSTAR Epo-Trac radioimmunoassay-increased significantly by 28 +/- 9% at 24 h post-exercise in 11 participants, who also had an arterial oxyhaemoglobin saturation < or = 91% (P < 0.05). Decreased ferritin levels and increased reticulocyte counts were observed at 96 h post-exercise. However, no significant changes in erythropoietin levels were observed in nine non-desaturating athletes and eight non-exercise controls. Good agreement was shown between arterial oxyhaemoglobin saturation and percent estimated oxyhaemoglobin saturation (limits of agreement = -3.9 to 3.7%). In conclusion, short supramaximal exercise can induce both hypoxaemia and increased erythropoietin levels in well-trained individuals. The decline of arterial hypoxaemia levels below 91% during exercise appears to be necessary for the exercise-induced elevation of serum erythropoietin levels. Furthermore, reflective probe pulse oximetry was found to be a valid predictor of percent arterial oxyhaemoglobin saturation during supramaximal exercise when percent estimated oxyhaemoglobin saturation > or = 86%.  相似文献   
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Gymnastics vaulting relies on a specialized take‐off board for propulsion during the take‐off phase of the vault. There is little information on the vault board and its behaviour. The aim of this study was to characterize the behaviour of the vault board during handspring drill take‐offs of young male gymnasts (n = 36). The side of the top surface of the vault board and the wooden base were marked with three reflective markers, placed at the end of the vault board nearest the vault table and the centres of the two rearmost coil springs. The vault board surface was divided into two areas, rear and middle, based on marker location. The gymnasts’ groups were determined from the location of the gymnast's lateral malleolus at vault board contact. Landings with the malleolus directly above or behind the rearmost marker were considered rear landings; landings with the malleolus forward of the rearmost marker were considered middle landings. Marker movements were automatically digitized and the right malleolus was hand digitized at 120 Hz. The maximum vertical displacement, vertical deflection time, and vertical velocity at take‐off of the vault board markers did not differ statistically between board contact groups (all p > 0.05). The lateral malleolus velocity components also did not differ between board contact groups. Some low to moderately strong correlations were observed between the various marker displacements, durations and take‐off velocities. Modest correlations were obtained between board markers and right malleolus velocities. The results indicate that foot contact on the vault board, as defined here, did not result in differences in board marker behaviour or right lateral malleolus velocities. This information does not support the idea that vault board contacts at the rear of the vault board are worse than contacts near the middle of the vault board. More research is needed to ascertain the role of the vault board's vibration characteristics to whole body actions that are observed in the subsequent preflight phase.  相似文献   
80.
Twenty‐three preschool‐age children, 3;6 (years; months) to 4;1, were videotaped separately with their mothers and fathers while each mother and father read a different unfamiliar storybook to them. The text from the unfamiliar storybooks was parsed and coded into story grammar elements and all parental extratextual utterances were transcribed and coded for (1) their relationship to the story grammar elements found within the storybook, and (2) the natural strategies parents used to direct their children's attention to these elements. Children's overall exposure to story grammar elements during book reading was also explored for its relationship to their language abilities. Results indicated that parents focused significantly more on the resolution, attempt, and consequence compared to the initiating event and plan, and most frequently used the text and pictures as strategies for recruiting their children's attention to the story grammar elements within the book. In addition, the frequency of parental utterances related to story grammar elements was negatively correlated with children's language abilities. This study did not examine the complexity or depth of parental utterances related to story grammar elements. These findings provide initial evidence that children may derive their understanding of story grammar at least in part through their parents' extratextual discussions during parent–child book reading.  相似文献   
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