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61.
Ortiz R Jiménez JE García Miranda E Guzmán Rosquete R Hernández-Valle I Rodrigo M Estévez A Díaz A Hernández Expósito S 《Journal of learning disabilities》2007,40(1):80-92
The aims of this study were (a) to determine whether Spanish children with reading disabilities (RD) show a speech perception deficit and (b) to explore the locus and nature of this perceptive deficit. A group of 29 children with RD, 41 chronological age-matched controls, and 27 reading ability-matched younger controls were tested on tasks of speech perception. The effect of linguistic unit (word vs. syllable) and type of phonetic contrast (voicing, place and manner of articulation) were analyzed in terms of the number of errors and the response time. The results revealed a speech perception deficit in Spanish children with RD that was independent of the type of phonetic contrast and of linguistic unit. 相似文献
62.
Boisnoir A Decker L Reine B Natta F 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(2):215-223
Biomechanical analyses using synchronized tools [electromyography (EMG), motion capture, force sensors, force platform, and digital camera] are classically performed in a laboratory environment that could influence the performance. We present a system for studying the running sprint start that synchronizes motion capture, EMG, and ground reaction force data. To maximize motion capture (Vicon 612 with six cameras), a special dim environment was created in the stadium. "Classical" tools were combined with "purpose-built" tools intended to analyse the different aspects of movement. For example, a synchronization system was built to create a common time-base for all data recordings and a portable EMG system was synchronized by a cable that was "disconnected" by the athlete's movement out of the blocks. This disconnection represented an independent event recorded by different tools. A "gap" was measured for some sprint start events between kinetic and kinematic (motion capture) data. Calibration results, measurements of time "gap", and duration of the independent event were used to validate the accuracy of motion capture and the synchronization system. The results validate the entire experimental set-up and suggest adjustment values for motion capture data. This environment can be used to study other movements and can easily be applied to several sports. 相似文献
63.
Comparison of two Actigraph models for assessing free-living physical activity in Indian adolescents
Corder K Brage S Ramachandran A Snehalatha C Wareham N Ekelund U 《Journal of sports sciences》2007,25(14):1607-1611
This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length. 相似文献
64.
In this study, we investigated the adjustments to posture, kinematic and temporal characteristics of performance made by lower limb amputees during the last few strides in preparation for long jump take-off. Six male unilateral trans-femoral and seven male unilateral trans-tibial amputees competing in a World Championships final were filmed in the sagittal plane using a 100-Hz digital video camera positioned so that the last three strides to take-off were visible. After digitizing using a nine-segment model, a range of kinematic variables were computed to define technique characteristics. Both the trans-femoral and trans-tibial athletes appeared to achieve their reduction in centre of mass during the flight phase between strides, and did so mainly by extending the flight time by increasing stride length, achieved by a greater flexion of the hip joint of the touch-down leg. The trans-tibial athletes appeared to adopt a technique similar to that previously reported for able-bodied athletes. They lowered their centre of mass most on their second last stride (-1.6% of body height compared with -1.4% on the last stride) and used a flexed knee at take-off on the last stride, but they were less able to control their downward velocity at touch-down (-0.4 m x s(-1)). Both this and their restricted approach speed (8.9 m x s(-1) at touch-down), rather than technique limitations, influenced their jump performance. The trans-femoral athletes lowered their centre of mass most on the last stride (-2.3% of body height compared with -1.6% on the second last stride) and, as they were unable to flex their prosthetic knee sufficiently, achieved this by abducting their prosthetic leg during the support phase, which led to a large downward velocity at touch-down (-0.6 m x s(-1)). This, combined with their slower approach velocity (7.1 m x s(-1) at touch-down), restricted their performance. 相似文献
65.
Luliang Huang Shufeng Li Weiye Huang Helanlin Xiang Jianhua Jin Alexei A.Oskolski 《国家科学评论(英文版)》2023,(4):13-15
<正>The Pleistocene was a time of repeated glaciations that severely affected the land biota over large areas of Eurasia and North America. Drastic climatic fluctuations during the Pleistocene drove largescale extinctions, migrations and diversification in plant and animal populations.These dramatic processes had a strong impact on the distribution of modern flora and fauna. 相似文献
66.
Nicholas A.Kotov 《国家科学评论(英文版)》2023,(5):106-108
<正>Engineering of composites mimicking load-bearing materials from living organisms is essential for sustainable economic development and successful resolution of current and future bottle-necks of chemical,automotive,aviation,biomedical,and robotic technologies.As pointed out by G.Wiedemann[1]in 1853 and M.F.Ashby et al. 相似文献
67.
Wenbo Chen Kyra L.A.Cloosterman Sita M.A.Bierma-Zeinstra Marienke van Middelkoop Robert-Jan de Vos 《运动与健康科学(英文)》2024,(2):256-263
Background:Achilles tendinopathy(AT) is a common problem among runners.There is only limited evidence for risk factors for AT,and most studies have not defined the AT subcategories.No study has compared the incidence and risk factors between insertional AT and midportion AT,though they are considered distinct.This study aimed to assess incidence and risk factors of AT based on data from a large prospective cohort.The secondary aim was to explore differences in risk factors between insertional an... 相似文献
68.
近年来,在学术界对於中俄关系史的研究不断增多,但是对於两国文化交流的研究还十分不足。本文讲述了清末北京的第一位俄语教师阿.弗.波波夫在外语学校“同文馆”的工作情况,以及他对於中国的记录。 相似文献
69.
H.A.Vanderbeek 《教育与职业》1924,(0)
万特克先生为美国工业专家任南洋大学.土木科科长多年.现任无锡实业学校校长.以东吴第四中学改组.分设机械工科.木工科.又规办建筑部.木材部.以营业收入.补充校费.对于提倡我国职业教育.甚具热忱.常与本社讨论关于职业教育方面种种问 相似文献
70.
根据半个多月以来、全方面的问卷调查统计,针对"如果给你一台多啦A梦的时间穿梭机,你最想回到什么时候?"这一问题,得到的回答是:75 6%的学生想要回到童年的纯真时代;81.9%的已婚男性想要回到结婚之前的无烦恼时光;100%的成年女性想回到年轻20岁的少女时光;33.7%的无疾病老人安于现状,表示不想回到任何时间段;作为和我一起刚刚步入社会的上班族来说,最想时光倒流回到大学的浪漫时光。但是我想对于"太空易"来说,他最希望能回到2007年6月30日——2007年NBA选秀大会。 相似文献