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151.
The aim of this study was to investigate, for typical shoes and surfaces used in tennis, the relative role of the shoe and
surface in providing cushioning during running. Five test surfaces ranging from concrete to artificial turf were selected,
together with two shoe models. Impact absorbing ability was assessed mechanically using drop test procedures and biomechanically
using peak magnitude and rate of loading of impact force and peak in-shoe pressure data at the lateral heel. Differences in
biomechanical variables between shoe-surface combinations were identified using a two-way ANOVA (p < 0.05). Mechanical test results were found to rank the surfaces in the same order regardless of the shoe model, suggesting
that the surface is influential in providing cushioning. However, for all mechanical and biomechanical (p < 0.05) variables representing impact absorbing ability, it was found that the difference between shoes was markedly greater
than the differences between surfaces. The peak heel pressure data were found to rank the surfaces in the same order as the
mechanical tests, while impact force data were not as sensitive to the changes in surface. Correlations between mechanical
and biomechanical impact absorption highlighted the importance of testing the shoe-surface combination in mechanical tests,
rather than the surface alone. In conclusion, mechanical testing of the shoe-surface combination was found to provide a strong
predictor of the impact absorbing ability during running if pressure data were used. In addition, for typical shoe-surface
combinations in tennis, the shoe was found to have more potential than the surface to influence impact loading during running.
Finally, in-shoe pressure data were found to be more sensitive than force plate data to changes in material cushioning. 相似文献
152.
Mick E Biederman J Faraone SV 《Journal of learning disabilities》2000,33(4):314; author reply 314-314; author reply 316
153.
Emiliya S. Egorova Alyona V. Borisova Leysan J. Mustafina Alina A. Arkhipova Rashid T. Gabbasov Anastasiya M. Druzhevskaya 《Journal of sports sciences》2014,32(13):1286-1293
AbstractResearch concerned with predictors of talent in football has highlighted a number of potentially important and partially inherited measures such as body size, anaerobic power, aerobic capacity, agility, psychological profile, game intelligence and susceptibility to injuries. Genotyping for performance-associated DNA polymorphisms at an early age could be useful in predicting later success in football. The aim of the study was to investigate individually and in combination the association of common gene polymorphisms with football player’s status. A total of 246 Russian football players and 872 controls were genotyped for 8 gene polymorphisms, which were previously reported to be associated with athlete status. Four alleles (ACE D, ACTN3 Arg577, PPARA rs4253778 C and UCP2 55Val) were first identified, showing discrete associations with football player’s status. Next, we determined the total genotype score (TGS, from the accumulated combination of the 4 polymorphisms, with a maximum value of 100 for the theoretically optimal polygenic score) in athletes and controls. The mean TGS was significantly higher in football players (52.0 (17.6) vs. 41.3 (15.5); P < 0.0001) than in controls. These data suggest that the likelihood of becoming a football player depends on the carriage of a high number of “favourable” gene variants. 相似文献
154.
155.
In Information Retrieval, since it is hard to identify users’ information needs, many approaches have been tried to solve
this problem by expanding initial queries and reweighting the terms in the expanded queries using users’ relevance judgments.
Although relevance feedback is most effective when relevance information about retrieved documents is provided by users, it
is not always available. Another solution is to use correlated terms for query expansion. The main problem with this approach
is how to construct the term-term correlations that can be used effectively to improve retrieval performance. In this study,
we try to construct query concepts that denote users’ information needs from a document space, rather than to reformulate initial queries using the term correlations
and/or users’ relevance feedback. To form query concepts, we extract features from each document, and then cluster the features into primitive concepts that are then used to form
query concepts. Experiments are performed on the Associated Press (AP) dataset taken from the TREC collection. The experimental evaluation
shows that our proposed framework called QCM (Query Concept Method) outperforms baseline probabilistic retrieval model on
TREC retrieval. 相似文献
156.
157.
A. A. Akhrem V. Z. Rakhmankulov K. V. Yuzhanin 《Scientific and Technical Information Processing》2017,44(6):406-411
In this paper, decomposition methods for multidimensional data hypercubes of OLAP systems are investigated. Criteria for reducing the computational complexity of the decomposition methods are presented and comparisons are made with the traditional solutions of multidimensional data analysis problems. Examples illustrating the application of these criteria to investigating the dynamics of computational complexity changes for specific types of reduction problems are considered. 相似文献
158.
Filippo Abbondanza Philip S. Dale Carol A. Wang Marianna E. Hayiou-Thomas Umar Toseeb Tanner S. Koomar Karen G. Wigg Yu Feng Kaitlyn M. Price Elizabeth N. Kerr Sharon L. Guger Maureen W. Lovett Lisa J. Strug Elsje van Bergen Conor V. Dolan J. Bruce Tomblin Kristina Moll Gerd Schulte-Körne Nina Neuhoff Andreas Warnke Simon E. Fisher Cathy L. Barr Jacob J. Michaelson Dorret I. Boomsma Margaret J. Snowling Charles Hulme Andrew J. O. Whitehouse Craig E. Pennell Dianne F. Newbury John Stein Joel B. Talcott Dorothy V. M. Bishop Silvia Paracchini 《Child development》2023,94(4):970-984
Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions. 相似文献
159.
P.V.K. Sasidhar P. Gopal Reddy 《The Journal of Agricultural Education and Extension》2013,19(4):387-407
Abstract Purpose: The purpose of this study was to identify and rank the SWOT issues of India's veterinary and animal science education. Design: The data were collected at the Indian Veterinary Research Institute (IVRI) from 168 post-graduate students. The two surveys generated 72% (N=121) and 68% (N=114) response rates, respectively. In the first stage, the vital SWOT issues were listed by respondents and in the second stage, they ranked the top eight issues on a Likert scale. Findings: Uniform curriculum; merit-based admissions; and huge demand and employment prospects were perceived as major strengths. Gaps in curriculum revision and inadequate faculty, colleges and hands-on experience were perceived as key weaknesses. Regular curriculum revisions; novel instructional methods; and single admission tests were important opportunities perceived. Out-dated education model; urban biased admissions; and regional barriers were the major threats perceived. Practical implication: The SWOT issues identified are similar to those faced by veterinary education programmes in many countries with minor variations. Originality/value: The findings are of interest for veterinary faculties in developing and under-developed countries to harmonize their veterinary education systems on par with global norms. The related implications for policy and future directions are discussed. 相似文献
160.
Giles LV Warburton DE Esch BT Fedoruk MN Rupert JL Taunton JE 《Journal of sports sciences》2012,30(3):261-267
The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males. 相似文献