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991.
The aim of this study was to examine the consistency or reproducibility of measuring cycling peak power in children and adults. Twenty-seven pre-pubertal girls and boys and 27 female and male physical education students (age 9.8 +/- 0.5 and 24.4 +/- 4.3 years, respectively; mean +/- s) participated in the study. All participants performed five tests over 15 days and underwent a habituation session before the study. Each test included four sprints against four different braking forces. We found that braking forces of 7.5% of body weight in children and 10% of body weight in adults were too high for most of the participants to elicit maximal cycling power. Unlike the children, the physical education students improved their performance between session 1 and session 2 (1025 +/- 219 vs 1069 +/- 243 W; P < 0.001). Therefore, to obtain reproducible measures of cycling peak power, a habituation session including a complete test protocol (i.e. warm-up plus three sprints) is highly recommended. When the protocol included three sprints in children and at least two sprints in adults, measurement of cycling peak power was found to be highly reliable (test-retest coefficient of variation approximately 3%). Finally, to avoid performance fluctuations, especially over several consecutive evaluations (e.g. longitudinal studies), it is necessary to maintain high motivation in children. 相似文献
992.
993.
A review of the archival literature, including records and information management, indicates that archivists’ have shown over
the last two decades an interest in program evaluation. The sparceness of the literature on the subject suggests a gap in
an articulate body of knowledge, based on solid theoretical and methodological foundations, for evaluation of archival programs
and activities. However, if they have not particularly investigated the subject from a theoretical perspective, archivists
have developed in their different organizations and working environment practical knowledge of and experience with program
evaluation. In large corporations as well as in public bureaucracies, they have been part of or subjected to specific or generic
program evaluation initiatives conducted by internal and external evaluators. But archivists might need now to go some steps
further and to look from a critical perspective at what is needed in order to get full benefit from program evaluation. 相似文献
994.
995.
Elmgren Claes Rom´n Ola Sjölund Maivor Wahlén Staffan Östling Malin 《Tertiary Education and Management》1999,5(3):245-259
The article aims at critically discussing the role and position of a buffer agency from the point of view of some of its different tasks, viz. accreditation, quality audit, support of academic leadership and internal quality enhancement. The contribution seeks to illuminate the conflicting roles of a buffer organisation in the light of these tasks and pressures from the government and higher education institutions. It concludes that the different roles can support and complement each other, and that change is best accomplished by emphasising support in the early stages of the establishment of a national quality assurance system. 相似文献
996.
Antonio Maldonado Andrés Catena Antonio Cándido Inmaculada García 《Learning & behavior》1999,27(2):168-180
A noncontingent experience affects the subsequent detection of positive and negative contingencies between the same events. Experiments 1 and 2 showed that such preexposure can produce both an impairment in the detection of subsequent positive contingency and a facilitation of a negative one, independent of the level of contingency during the contingent phase. Experiment 3 raised difficulties for a model that assumes that associations to the context can explain this asymmetrical effect. Experiment 4 suggested that the different weights usually assigned to the different types of trials when computing the contingency between events can change as a result of a noncontingent experience with the same events. This change supports an account of the asymmetrical effect by a belief revision model based on a mechanism that updates the weights of the different trial types as a function of previous experience. More generally, the belief revision model is a statistical (i.e., nonassociative) model of learning that is capable of accounting for trial-order effects, which have long posed problems for statistical models. 相似文献
997.
Before a higher education institution can develop international impact and reputation, it must first have developed its regional impact and reputation. Universities can contribute to the creation of wealth in given regions in a number of ways, not the least of which is technology transfer, the creation of firms and other spin‐off activities, and the furtherance of the their reputations for excellence. Staff and students spend a good deal of money in such regions, thus increasing regional wealth, and if given institutions pursue entrepreneurial policies in regard to the course programmes that they offer, their graduates will not only find nearby employment but will create employment for others. The “Innova” Project of the Polytechnic University of Catalonia is an illustration of how a major regional university is attempting to apply new teaching models to enhance entrepreneurial culture in the Barcelona area of Spain and thereby to increase regional human capital. 相似文献
998.
Reading and spelling errors of vowels are reported in many studies (Bryson and Werker 1989; Fowler, Liberman, and Shankweiler
1977; Fowler, Shankweiler, and Liberman 1979; Goswami 1993; Landerl, Wimmer, and Frith 1997; Shankweiler and Liberman 1972).
The present study tested the hypothesis that spelling errors involving vowels are linked to difficulties in vowel perception.
Second to fourth graders (total n=155) were divided into five groups according to reading skill and were tested on a variety of measures involving vowel identification,
vowel discrimination, and vowel spelling. Despite little difficulty on the vowel discrimination tasks, participants made many
errors on the vowel identification measures. Vowel identification errors were linearly associated with reading skill with
least skilled readers having significantly more difficulty with stressed “short” vowels as in dip than with stressed “long” vowels as in deep, presented in identical contexts. Vowel identification errors were also associated with vowel spelling errors. It is hypothesized
that errors in vowel spelling may relate to weak access to the phoneme at the oral language level and may indicate a lack
of constancy in the representation of vowels by less skilled readers. Weaknesses in vowel perception can be detected with
a simple vowel identification test in which phonological similarity of test items is used as linguistic manipulation, and
where phonemes must be identified based on presentation of a single test item in a forced choice format. 相似文献
999.
Pedro Ángel Latorre Román Fernando Redondo Balboa Juan Párraga Montilla Víctor Manuel Soto Hermoso Pedro José Consuegra González Felipe García Pinillos 《Journal of sports sciences》2019,37(5):477-483
The purpose of this study was to determine the foot strike patterns (FSP), rearfoot position at initial contact (RPic, i.e., No INV/EVE) and foot rotation in children in relation to age. A total of 932 children aged 3 to 16 years participated in this study. A sagittal and frontal-plane video was recorded using a high-speed camcorder to analyse these variables. There is a significant increase (p < 0.001) of rearfoot strike patterns (RFS) prevalence in relation to age; e.g. preschool children (3–6 years old) displayed an RFS prevalence 46.65% and the adolescent population(15–16 years old) an RFS prevalence 92.20%. The total RFS prevalence in all samples was 69.25%. There was a significant reduction (p < 0.001) of prevalence of RPic in relation to age groups; preschool children displayed a prevalence of RPic 60.37% and the adolescent population 10%. There was a significant reduction (p < 0.001) of prevalence of no foot rotation in relation to age groups; preschool children displayed a prevalence of no foot rotation 48.95% and the adolescent population 13.55%. In conclusion, FSP in children are influenced by age. It is noteworthy that the RFS prevalence of children is lower in comparison to the adult population. 相似文献
1000.
Irene Rodríguez-Gómez Soraya Martín-Manjarrés María Martín-García Sara Vila-Maldonado Ángel Gil-Agudo Luis M. Alegre 《Journal of sports sciences》2019,37(7):717-725
Spinal cord injury (SCI) derives in loss of bone mineral content (BMC) and bone mineral density (BMD). However, physical activity is an important determinant in bone mass acquisition, which is partially mediated through the lean mass (LM). The aim was to examine the effect of cardiorespiratory fitness (CRF) on BMD and BMC arms of adult males with SCI and able-bodied controls using the arm LM as a mediator variable. Thirty able-bodied men and thirty men with SCI participated. BMC and BMD were analysed by DXA, and indirect calorimetry was used to calculate VO2peak during a progressive arm-cranking test. When groups were divided by the amount of LM, the subgroup with highest LM had significantly higher arm BMC compared to the lowest LM subgroup (p ≤ 0.05) in both SCI and able-bodied groups. Moreover, same differences were found when confidence intervals were analysed. Only in the SCI group, arm LM mediated the relationship between bone mass and CRF at 30.9%, as indicated by the Sobel test (z = 2.17 and z = 2.04 for BMC and BMD, respectively). In conclusion, LM mediates the indirect association between CRF and bone health, specifically in the arms. This finding highlights the importance of having an adequate CRF for the maintenance of good bone health in SCI men. 相似文献