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71.
Peijie Chen Lijuan Mao George P.Nassis Peter Harmer Barbara E.Ainsworth Fuzhong Li 《运动与健康科学(英文)》2020,9(2):103-104
The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7. 相似文献
72.
Liezel Hurter Alex V. Rowlands Stuart J. Fairclough Karl C. Gibbon Zoe R. Knowles Lorna A. Porcellato 《Journal of sports sciences》2019,37(16):1910-1918
This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9–10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77–78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results. 相似文献
73.
Although there have been a number of studies that compared the test results of the Wide Range Achievement Test (WRAT) and the Peabody Individual Achievement Test (PIAT), none had been accomplished with a group of college-aged learning disabled students. Indeed, few researchers had investigated populations over 16 years of age, and none had compared grade scores and standard scores with appropriate subtest scores as derived from these two instruments. With the recent emphasis on postsecondary education for the learning disabled, it is deemed critical that researchers should develop a data base for study of this population. The current research demonstrated that although both tests purport to measure academic achievement in reading, spelling, and arthmetic, in reality, significantly different scores are derived when WRAT (1965, 1978) norms are compared to PIAT (1970) norms as stated in grade scores and standard scores. These significant differences in the grade and standard scores clearly indicate that the WRAT and the PIAT, particularly in regard to arthmetic and to a lesser degree to reading, are not interchangeable instruments of academic achievement. 相似文献
74.
Barbara Larrivee 《Psychology in the schools》1982,19(3):374-379
Nearly 1000 regular classroom teachers were administered a scale designed to assess attitude toward mainstreaming. To determine the underlying dimensions of teacher attitude, a factor analysis of the intercorrelations of the items was conducted. Five dimensions were isolated that accounted for 52.4% of the variance. They were defined as attitude toward: (a) general philosophy of mainstreaming, (b) classroom behavior of special needs children, (c) perceived ability to teach the special needs child, (d) classroom management with special needs children, and (e) academic and social growth of the special needs child. 相似文献
75.
Campbell AM Zanta CA Heyer LJ Kittinger B Gabric KM Adler L Schulz B 《CBE life sciences education》2006,5(4):332-339
We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula. 相似文献
76.
Energy balance of locomotion with pedal-driven watercraft 总被引:1,自引:0,他引:1
In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output (Wtot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake (VO2) allowed the computation of the "overall" efficiency of locomotion (etao = Wtot/VO2). Mean etao was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, Wtot was then obtained from etao and measures of VO2. The power to overcome (passive) drag was calculated as Wd = D x v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as etap = Wd/Wtot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in etap and Wd explain why at the highest speed tested (approximately 3 m s(-1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m s-1). 相似文献
77.
Joan N. Vickers Joe Causer Michael Stuart Elaine Little Sean Dukelow Marc Lavangie 《European Journal of Sport Science》2017,17(1):109-117
AbstractA “look-up line” (LUL) has been proposed for ice hockey, which is an orange 1?m (40′) warning line (WL) painted on the ice at the base of the boards. The LUL purports to provide an early warning to players to keep their head up prior to and as they are being checked. We determined if players looked up more on a rink with the LUL compared to a traditional Control rink. Elite offensive (O) and defensive (D) players competed 1 vs. 1, while wearing an eye tracker that recorded their quiet eye (QE) and fixation and tracking (F-T) and an electrogoniometer that measured head angle. External cameras recorded skate duration during four skate phases: P1 preparation, P2 decision-making, P3 cut to boards, P4 contact. The QE was the final fixation prior to contact between O and D as they skated towards and across the WL during P3 and P4. Skate phase durations (%) did not differ by rink or rink by position. More QE and F-T occurred on the WL on the LUL rink than on the Control. The expected increase in head angle on the LUL rink did not occur during P3 or P4. Post-hoc results also showed O and D skated further from the boards on the LUL rink, suggesting the players preferred to control the puck on white ice, rather than the orange colour of the LUL rink. More research is needed to determine if these results apply to the competitive setting. 相似文献
78.
Barbara Hruska 《Multicultural Perspectives》2013,15(4):3-12
This study identifies how the contextual features of an elementary school setting shaped and often restricted bilingual kindergarten students' access to friendships within their grade-level English-dominant classroom. Data demonstrate how students utilized a teacher-designed lunch card routine to initiate, maintain, and display friendships in addition to indicating their lunch selection. Findings from the study prompted changes in my instructional practices as well as in the ESL and bilingual program design at the school in order to allow greater interaction between native English and native Spanish speakers. Implications of these findings include the significance of social relationships for language learning, for gaining status, and for motivating bilingual students to remain in school over the course of their K-12 education. 相似文献
79.
Desalination is a relatively new intervention in the field of conservation of architectural heritage. Especially the desalination of immovable objects, such as masonry structures, is still a trial-error practice. In the field, different desalination materials and methods are used, sometimes with unsatisfactory results. Better understanding of the desalination process is needed in order to support the conservator with clear guidelines for choosing a suitable desalination material and method. The research presented in this paper constitutes the first step towards the development of a modular system of poultices, which can be adapted, i.e. fine-tuned to different types of substrates. Starting point is to make use of advection, i.e. the transport of salt ions with water flow. This transport mechanism is faster than diffusion and the application on immovable objects is relatively easy. In order to optimize salt extraction, a poultice working by advection should have smaller pores than the substrate. Starting from this principle the pore sizes of different desalination materials (sand, cellulose, kaolin and bentonite) mixed in different proportions, have been measured. Interesting results were obtained, showing that the desalination materials commonly used in the field are often not the most suitable ones. On the basis of the results, recipes for poultices, adapted to a specific substrate, can be formulated. 相似文献
80.
Results of the Vocabulary, Reading Comprehension, and Mathematics Concepts subtests for third-, sixth-, and eighth-grade students who took Form 5 of the Iowa Tests of Basic Skills in the 1976 school year were analyzed for sex bias. Statistical significance was found for each subtest for all of the grade levels. Follow-up analyses considered skill classification, sex-stereotypicalness, and item location of the items contributing to the statistical significance. No trends for these factors were found within each grade level for the four subtests considered. For all subtests, fewer items are identified at the third-grade level than for sixth or eighth grade, and these items, in general, favored boys. For the older students, when items are found to function differently for boys and girls, nearly half favor each sex. On the whole, little evidence for sex bias was found for the four subtests and three grade levels examined. 相似文献