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141.
The universities and the government in Sri Lanka 总被引:1,自引:0,他引:1
Kingsley De Silva 《Minerva》1978,16(2):251-272
142.
All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling. 相似文献
143.
M Martín-Matillas FB Ortega JR Ruiz D Martínez-Gómez G Vicente-Rodríguez A Marcos L Béghin A Kafatos M González-Gross M Zaccaria D Molnár S De Henauw M Sjöström LA Moreno MJ Castillo On Behalf Of The Helena Study 《Journal of sports sciences》2012,30(13):1329-1335
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?0.05); and mother's and sisters' physical activity engagement were positively associated with higher muscular strength in adolescents (P?0.05). Furthermore, father's physical activity encouragement was positively linked to physical fitness (all fitness components) in adolescents (P?0.05). Interventions aimed at improving physical fitness in young people might be more successful when family members, particularly mothers and fathers, are encouraged to engage in physical activity and support adolescents' physical activity. 相似文献
144.
This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent. 相似文献
145.
Enrique Herrera-Viedma Guy De Tré Slawomir Zadrozny Jose Angel Olivas 《Information processing & management》2012
Soft Computing (SC) tools present a great potential in real-life problems related with engineering, industrial applications, medicine, finances, etc. In this special issue we present a set of seven papers that report original research about the use of SC techniques to solve the problems in the field of information access on the Web. 相似文献
146.
In two experiments, we examined how preexposure to discriminative stimuli and introduction of a 21-day retention interval
affected the latent inhibition (LI) and perceptual learning (PL) of rats in a choice-maze discrimination task. Experimental
groups were preexposed to three wall patterns, one in each of three arms of a maze. Control groups were preexposed only to
white arms. PL groups were trained to discriminate A versus B, and LI groups, to discriminate A or B versus C. The A and B
patterns shared many elements not shared with the C pattern. In Experiment 1, both at the end of training and after the subsequent
retention interval, the PL groups performed better than controls, whereas the LI groups performed worse. In Experiment 2,
inserting the 21-day retention interval between preexposure and discrimination training disrupted final measures of LI but
not PL performance. Implications for current concepts of PL and LI are discussed. 相似文献
147.
Attempting to push early modern presentism to the radical, logical conclusion of a more personal historicism, this essay draws on a number of interpretive practices and theoretical insights – Stephen Greenblatt’s self-reflectivity, Toni Morrison’s ‘rememory’, Marianne Hirsch’s ‘postmemory’, bell hooks’s ‘passion of experience’, and Linda Charnes’s alternative historicism – to establish the ethical and interpretive significance of my own painful situatedness as an African American man in Renaissance/Early Modern studies. Specifically, I illustrate that significance in a reading of Richard Mulcaster’s Positions Concerning the Bringing Up of Children, a sixteenth-century educational treatise that responds, as I argue, to early modern educational access and social mobility with an insidiously complex, exclusionary admissions policy. 相似文献
148.
As secondary students’ interest in science is decreasing, schools are faced with the challenging task of providing adequate instruction to engage students—and more particularly the disadvantaged students—to learn science and improve their science inquiry skills. In this respect, the integration of Web-based collaborative inquiry can be seen as a possible answer. However, the differential effects of Web-based inquiry on disadvantaged students have barely been studied. To bridge this gap, this study deals with the implementation of a Web-based inquiry project in 19 secondary classes and focuses specifically on gender, achievement level, and academic track. Multilevel analysis was applied to uncover the effects on knowledge acquisition, inquiry skills, and interest in science. The study provides quantitative evidence not only that a Web-based collaborative inquiry project is an effective approach for science learning, but that this approach can also offer advantages for students who are not typically successful in science or who are not enrolled in a science track. This approach can contribute to narrowing the gap between boys and girls in science and can give low-achieving students and general-track students an opportunity to develop confidence and skills for learning science, bringing them to a performance level that is closer to that of high-achieving students. 相似文献
149.
150.
Karen M. La Paro Bridget K. Hamre Jennifer Locasale-Crouch Robert C. Pianta Donna Bryant Dianne Early 《Early education and development》2013,24(4):657-692
Research Findings: Using observational data gathered in 730 kindergarten classrooms in 6 states, the present study focuses on the quality of children's learning opportunities in kindergarten classrooms. Findings show that overall, children experience moderate to low levels of quality in the areas of classroom organization and instructional support in kindergarten. Results are also presented in comparison to children's experiences in the pre-kindergarten year. These comparisons indicate that kindergarten children spend a greater proportion of the school day in language arts, math, and whole-group instruction and less time in centers than they do in pre-kindergarten. An examination of predictors of kindergarten classroom quality indicated that program characteristics (i.e., adult–child ratio, length of school day) and teacher psychological variables (i.e., beliefs and depressive symptoms) were stronger predictors of classroom quality than were teacher experience and educational background. Practice or Policy: Findings are discussed in terms of implications for children's academic and social development in kindergarten as well as for kindergarten teacher preparation and development. 相似文献