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241.
Analytical methods to assess thigh muscle balance need to provide reliable data to allow meaningful interpretation. However, reproducibility of the dynamic control ratio at the equilibrium point has not been evaluated yet. Therefore, the aim of this study was to compare relative and absolute reliability indices of its angle and moment values with conventional and functional hamstring–quadriceps ratios. Furthermore, effects of familiarisation and angular velocity on reproducibility were analysed. A number of 33 male volunteers participated in 3 identical test sessions. Peak moments (PMs) were determined unilaterally during maximum concentric and eccentric knee flexion (prone) and extension (supine position) at 0.53, 1.57 and 2.62 rad · s–1. A repeated measure, ANOVA, confirmed systematic bias. Intra-class correlation coefficients and standard errors of measurement indicated relative and absolute reliability. Correlation coefficients were averaged over respective factors and tested for significant differences. All balance scores showed comparable low-to-moderate relative (<0.8–0.9) and good absolute reliability (<10%). Relative reproducibility of dynamic control equilibrium parameters augmented with increasing angular velocity, but not with familiarisation. At 2.62 rad · s–1, high (moment: 0.906) to moderate (angle: 0.833) relative reliability scores with accordingly high absolute indices (4.9% and 6.4%) became apparent. Thus, the dynamic control equilibrium is an equivalent method for the reliable assessment of thigh muscle balance.  相似文献   
242.
Understanding the effects of training in different footwear on sporting performance would be useful to coaches and athletes. Purpose: This study compared the effects of computerized agility training using 3 types of footwear on change-of-direction and balance performance in young adults. Method: Thirty recreationally active young adults (Mage = 22.8 ± 3.1 years; Mheight = 1.71 ± 0.7 m; Mbodymass = 73.4 ± 10.3 kg) were randomly assigned to a 6-week computerized agility training intervention in 1 of 3 footwear groups (n = 10/group): barefoot, minimal footwear, or traditional shoes. Participants had no previous barefoot or minimal-footwear training experience. Dependent variables included change-of-direction test time to completion, Star Excursion Balance Test, and single-leg stability evaluation. Testing was performed at the start of the training program, after 2 weeks, after 4 weeks, and at the end of the training program. Results: No group or time interactions were found for any of the dependent variables. Time main effects were observed for the performance measures of change of direction, Star Excursion, and single-leg-with-eyes-open stability evaluation. Participants improved in all 3 tests as early as 2 weeks into the intervention, with improvements continuing through the entire 6-week intervention. Conclusions: The lack of interaction and footwear effects suggests that agility and balance improvements during foot agility training are independent of footwear in a recreationally active young-adult population. Computerized agility training improves change-of-direction and balance performance within 2 weeks of training implementation. Future studies should consider footwear training effects in different populations, including frail older adults and athletes.  相似文献   
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Purpose: This study investigated the effect of summer camp session context on Russian girls’ physical activity (PA). Method: Girls (n = 32, Mage = 10.7 years, SD = 0.6 years) from a resident summer camp taking place in the Vologda Region of Russia were exposed to 1 session context/day (i.e., free play, organized with no choice, organized with choice) on Wednesday, Thursday, and Friday for 3 weeks, with the context order counterbalanced across the 3 weeks. The organized session sport/game changed weekly. The primary outcome was accelerometer-assessed PA. Repeated-measures mixed models were used to analyze all outcome data. Results: Findings showed that girls spent a greater percentage of session time (%time) in moderate-to-vigorous PA (p < .001; effect sizes between free play and organized with no choice and organized with choice, respectively = .60, .42) and moderate PA (p < .001; effect size = .57, .39) and a lower %time in light PA (p < .001; effect size = .55, .52) in organized PA contexts compared with free play. Conclusions: This study provides novel findings in a Russian setting, suggesting that a well-planned, organized camp session can elicit higher PA levels in girls, relative to a free-play session.  相似文献   
245.
This article provides an insight into the theorization of sōgō geijutsu or the work of total art during the postwar decades in Japan, primarily through the language of Hanada Kiyoteru, a notable communist critic during the 1950s, as a way to present a discursive precursor to what would be explored as intermedia in the 1960s. It is an attempt to trace the debates that were seen in journal Sōgō Bunka, which was established immediately after the war, and how the question of collectivity and collective production of art was discussed among the contributing critics, artists, and intellectuals. Totality as some may know already, is a problematic term that comes close to the wartime notion of ‘totality’, as it was employed for Japanese government's ideological deployment for its war efforts. Although the term has accrued a sinister ring, the critics mentioned in the article, especially Hanada, were determined to reclaim the term as a way of devising a postwar aesthetic-political platform. One important component of sōgō geijutsu was popular art and its relationship to the masses, as it was designed to relocate avant-garde art practices to the juncture of popular space and political praxis, while critiquing the modernist avant-garde art associated with high art. In addition to providing a fuller historiography of intermedia (or transmedia) in Japan, interrogating sōgō geijutsu also serves to shed some light on the complex and multivalent discourse of locating a ‘people’ and their communicative action. Through this history, the term totality gains a greater texture, no longer dismissible as a mere vestige of fascism in the minds of the Japanese artists and critics.  相似文献   
246.
This study was designed to obtain the perceptions of regular class teachers who taught children who had been in EMR programs, but had been decertified (D) and returned to regular classes in response to court cases and recent legislation. A cohort of regular class (RC) students were selected for comparative purposes. It was found that D students were placed into low ability classes; yet, teachers perceived D subjects to be significantly lower than RC students in both academic achievement and social acceptance. Only a small proportion of teachers indicated that the enrollment of D students had much impact on the regular class instructional program. However, the teachers were rather critical of the services received under the auspices of a transitional program, indicating in large part that the services were either not apparent or ineffective.  相似文献   
247.
This study compared the WISC-R and PPVT scores for a group of 65 students classified as mentally retarded, ranging in age from 7.5 to 14.5. Pearson product moments (r) and correlated t values were employed in the analysis of data. The evidence from the present study indicated that for this sample of mildly retarded children and youth, the PPVT IQ score is significantly higher than the Full Scale IQ from the WISC-R. The current findings indicate that the same general pattern exists for the WISC-R and PPVT as for the WISC and PPVT scores.  相似文献   
248.
Television     
This paper gives an outline of a new television system developed in the laboratories of RCA Victor Company, in Camden, N. J.The system is truly electrical and employs only electronic devices, without a single mechanically moving part.The translation of the visual image is accomplished by means of a vacuum tube called the iconoscope. This tube is a virtual electric eye and consists of a photo-sensitive mosaic corresponding to the retina of the human eye, and a moving electron beam representing the nerve of the eye. The image is projected optically on the mosaic and transformed within the tube into a train of electrical impulses, representing the illumination of individual points of the image.The reproduction of the image is accomplished by means of another vacuum tube, the kinescope, which transforms the electrical impulses back into the variation of light intensity through the bombardment of a fluorescent screen by the moving electron beam.The movement of the electron beams in both tubes, which is responsible for both transformations, is linear and divides the picture into a series of parallel lines. The movements are synchronized so that the instantaneous position of the beams with respect to a point in the picture is always identical. The synchronization is transmitted together with the picture signals, and operation of the receiver is completely automatic.The sensitivity of the iconoscope, at the present time, is approximately equal to that of a photographic film operating at the speed of a motion picture camera, permitting the transmission of outdoor scenes. The resolution is high, much higher than necessary for television images of the highest quality.The paper describes the theory of the system, its characteristics, mode of operation, and includes photographs of images obtained on the fluorescent screen of the receiver.  相似文献   
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