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81.
The Effect of Two-dimensional and Stereoscopic Presentation on Middle School Students’ Performance of Spatial Cognition Tasks 总被引:1,自引:1,他引:0
We investigated whether and how student performance on three types of spatial cognition tasks differs when worked with two-dimensional
or stereoscopic representations. We recruited nineteen middle school students visiting a planetarium in a large Midwestern
American city and analyzed their performance on a series of spatial cognition tasks in terms of response accuracy and task
completion time. Results show that response accuracy did not differ between the two types of representations while task completion
time was significantly greater with the stereoscopic representations. The completion time increased as the number of mental
manipulations of 3D objects increased in the tasks. Post-interviews provide evidence that some students continued to think
of stereoscopic representations as two-dimensional. Based on cognitive load and cue theories, we interpret that, in the absence
of pictorial depth cues, students may need more time to be familiar with stereoscopic representations for optimal performance.
In light of these results, we discuss potential uses of stereoscopic representations for science learning. 相似文献
82.
Victoria Reyes-García Eric Kightley Isabel Ruiz-Mallén Nuria Fuentes-Peláez Katie Demps Tomás Huanca Maria Ruth Martínez-Rodríguez 《International Journal of Educational Development》2010
Schooling and the knowledge acquired at school have been considered both a cause of loss of indigenous knowledge (because it opens pathways to the non-indigenous world and worldviews) and a potential remedy to its demise (if educational curricula is aligned with indigenous realities by giving instruction in local languages and incorporating local knowledge in school content). We test the association between academic and local environmental knowledge using data from a society of forager-horticulturalists in the Bolivian Amazon who were exposed to a partially contextualized school curriculum. We found that although schooling and academic knowledge bear a negative association with local knowledge the magnitude is low, probably because schooling was partially contextualized. Contextualized learning might help avoid that the provision of universal education comes at the cost of humanity's cultural diversity. 相似文献
83.
Katie Quy Jennifer Gibb Louise Neil Charlie Owen Marjorie Smith 《Emotional and Behavioural Difficulties》2018,23(3):230-244
Coping style plays an important role in children’s wellbeing. This paper describes the patterns of associations between children’s self-reported coping styles and symptoms of anxiety in order to determine whether particular dimensions are associated with better adjustment. Participants were 2566 children (1268 girls, 1298 boys) aged 7–11 years attending 15 schools in the South East of England. Results showed that aspects of coping were differentially associated with children’s self-reported anxiety. Patterns of association also varied by age and gender. Dimensions of coping were shown to form distinct adaptive and maladaptive coping styles which were also differentially associated with anxiety. Analysis of these styles indicated that it is the absence of maladaptive coping strategies, rather than the presence of adaptive strategies, that is significant in emotional wellbeing. These findings suggest that interventions designed to reduce or extinguish maladaptive coping styles may be of particular benefit in facilitating emotional wellbeing. 相似文献
84.
The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption ( V O 2peak ) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev·min -1 . The order of tests was randomized and they were separated by at least 2 days. Peak V O 2 was significantly higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Peak ventilation volume increased as a function of crank rate and was higher ( P ? 0.05) at 80 than at 60 rev·min -1 . Peak heart rate was higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Furthermore, 70 and 80 rev·min -1 resulted in an extended test time compared with 60 rev·min -1 . The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev·min -1 should be used to elicit V O 2peak and other physiological responses in arm crank ergometry. 相似文献
85.
The thermoregulatory responses of upper-body trained athletes were examined at rest, during prolonged arm crank exercise and recovery in cool (21.5 ± 0.9°C, 43.9 ± 10.1% relative humidity; mean ± s) and warm (31.5 &± 0.6°C, 48.9 - 8.4% relative humidity) conditions. Aural temperature increased from rest by 0.7 ± 0.7°C (P ? 0.05) during exercise in cool conditions and by 1.6 ± 0.7°C during exercise in warm conditions (P ? 0.05). During exercise in cool conditions, calf skin temperature decreased (1.5 ± 1.3°C), whereas an increase was observed during exercise in warm conditions (3.0 ± 1.7°C). Lower-body skin temperatures tended to increase by greater amounts than upper-body skin temperatures during exercise in warm conditions. No differences were observed in blood lactate, heart rate or respiratory exchange ratio responses between conditions. Perceived exertion at 45 min of exercise was greater than that reported at 5 min of exercise during the cool trial (P ? 0.05), whereas during exercise in the warm trial the rating of perceived exertion increased from initial values by 30 min (P ? 0.05). Heat storage, body mass losses and fluid consumption were greater during exercise in warm conditions (7.06 ± 2.25 J·g-1 ·°C-1, 1.3 ± 0.5 kg and 1038 ± 356 ml, respectively) than in cool conditions (1.35 ± 0.23 J·g-1·°C-1, 0.8 ± 0.2 kg and 530 ± 284 ml, respectively; P ? 0.05). The results of this study indicate that the increasing thermal strain with constant thermal stress in warm conditions is due to heat storage within the lower body. These results may aid in understanding thermoregulatory control mechanisms of populations with a thermoregulatory dysfunction, such as those with spinal cord injuries. 相似文献
86.
This study examined the effects of different work?–?rest durations during 40?min intermittent treadmill exercise and subsequent running performance. Eight males (mean?±?s: age 24.3?±?2.0 years, body mass 79.4?±?7.0?kg, height 1.77?±?0.05?m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (v-[Vdot]O2max) was attained with passive recovery between each one. The work?–?rest ratio was constant at 1:1.5 with trials involving short (6:9?s), medium (12:18?s) or long (24:36?s) work?–?rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% v-[Vdot]O2max. After 40?min, mean exercise intensity was greater during the long (68.4?±?9.3%) than the short work?–?rest trial (54.9?±?8.1% [Vdot]O2max; P?<?0.05). Blood lactate concentration at 10?min was higher in the long and medium than in the short work?–?rest trial (6.1?±?0.8, 5.2?±?0.9, 4.5?±?1.3?mmol?·?l?1, respectively; P?<?0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work?–?rest trials (P <?0.05). Plasma glucose concentration was higher in the long and medium than in the short work?–?rest trial after 40?min of exercise (5.6?±?0.1, 6.6?±?0.2 and 5.3?±?0.5?mmol?·?l?1, respectively; P?<?0.05). No differences were observed between trials for performance time (72.7?±?14.9, 63.2?±?13.2, 57.6?±?13.5?s for the short, medium and long work?–?rest trial, respectively; P = 0.17), although a relationship between performance time and 40?min plasma glucose was observed (P?<?0.05). The results show that 40?min of intermittent exercise involving long and medium work?–?rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work?–?rest duration. 相似文献
87.
88.
Katie J. Thralls Suneeta Godbole Todd M. Manini Eileen Johnson Loki Natarajan Jacqueline Kerr 《Journal of sports sciences》2013,31(20):2309-2317
ABSTRACTThis study compared five different methods for analyzing accelerometer-measured physical activity (PA) in older adults and assessed the relationship between changes in PA and changes in physical function and depressive symptoms for each method. Older adult females (N = 144, Mage = 83.3 ± 6.4yrs) wore hip accelerometers for six days and completed measures of physical function and depressive symptoms at baseline and six months. Accelerometry data were processed by five methods to estimate PA: 1041 vertical axis cut-point, 15-second vector magnitude (VM) cut-point, 1-second VM algorithm (Activity Index (AI)), machine learned walking algorithm, and individualized cut-point derived from a 400-meter walk. Generalized estimating equations compared PA minutes across methods and showed significant differences between some methods but not others; methods estimated 6-month changes in PA ranging from 4 minutes to over 20 minutes. Linear mixed models for each method tested associations between changes in PA and health. All methods, except the individualized cut-point, had a significant relationship between change in PA and improved physical function and depressive symptoms. This study is among the first to compare accelerometry processing methods and their relationship to health. It is important to recognize the differences in PA estimates and relationship to health outcomes based on data processing method.Abbreviation: Machine Learning (ML); Short Physical Performance Battery (SPPB); Center of Epidemiologic Studies Depression Scale (CES-D); Physical Activity (PA); Activity Index (AI); Activities of Daily Living (ADL) 相似文献
89.
Abstract In this study, we examined the effects of different work:rest durations during 20 min intermittent treadmill running and subsequent performance. Nine males (mean age 25.8 years, s = 6.8; body mass 73.9 kg, s = 8.8; stature 1.75 m, s = 0.05; [Vdot]O2max 55.5 ml · kg?1 · min?1, s = 5.8) undertook repeated sprints at 120% of the speed at which [Vdot]O2max was attained interspersed with passive recovery. The work:rest ratio was constant (1:1.5) with trials involving either short (6:9 s) or long (24:36 s) work:rest exercise protocols (total exercise time 8 min). Each trial was followed by a performance run to volitional exhaustion at the same running speed. Testing order was randomized and counterbalanced. Heart rate, oxygen consumption, respiratory exchange ratio, and blood glucose were similar between trials (P > 0.05). Blood lactate concentration was greater during the long than the short exercise protocol (P < 0.05), whereas blood pH was lower during the long than the short exercise protocol (7.28, s = 0.11 and 7.30, s = 0.03 at 20 min, respectively; P < 0.05). Perceptions of effort were greater throughout exercise for the long than the short exercise protocol (16.6, s = 1.4 and 15.1, s = 1.6 at 20 min, respectively; P < 0.05) and correlated with blood lactate (r = 0.43) and bicarbonate concentrations (r = ?0.59; P < 0.05). Although blood lactate concentration at 20 min was related to performance time (r = ?0.56; P < 0.05), no differences were observed between trials for time to exhaustion (short exercise protocol: 95.8 s, s = 30.0; long exercise protocol: 92.0 s, s = 37.1) or physiological responses at exhaustion (P > 0.05). Our results demonstrate that 20 min of intermittent exercise involving a long work:rest duration elicits greater metabolic and perceptual strain than intermittent exercise undertaken with a short work:rest duration but does not affect subsequent run time to exhaustion. 相似文献
90.
Suzanne E. Slenker James H. Price Stephen M. Roberts Stephen G. Jurs 《Research quarterly for exercise and sport》2013,84(4):371-378
Abstract The Health Belief Model was utilized to examine the knowledge, attitudes and beliefs of individuals regarding regular jogging. Based on an elicitation procedure developed by Martin Fishbein, a questionnaire was developed according to the theoretical tenets of the Health Belief Model and was found to be valid and reliable. Responses from 124 joggers and 96 nonexercisers were analyzed, and significant differences were found. Factors which accounted for the largest portion of predictable variance (40%) were barriers to action such as lack of time, job or family responsibilities, or weather constraints. As a whole, the results provided support for the Health Belief Model in that 61% of the variance in jogging behavior was determined. The study suggests that physical and health educators might more effectively change the behavior of sedentary individuals by utilizing strategies which address perceived obstacles to jogging. 相似文献