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211.
212.
Junichi Tajino Akira Ito Momoko Nagai Xiangkai Zhang Shoki Yamaguchi Hirotaka Iijima 《Journal of motor behavior》2013,45(5):397-406
Exposure to a microgravity environment leads to adverse effects in motion and musculoskeletal properties. However, few studies have investigated the recovery of altered locomotion and muscle atrophy simultaneously. The authors investigated altered locomotion in rats submitted to simulated microgravity by hindlimb unloading for 2 weeks. Motion deficits were characterized by hyperextension of the knees and ankle joints and forward-shifted limb motion. Furthermore, these locomotor deficits did not revert to their original form after a 2-week recovery period, although muscle atrophy in the hindlimbs had recovered, implying discordance in recovery between altered locomotion and muscle atrophy, and that other factors such as neural drives might control behavioral adaptations to microgravity. 相似文献
213.
The purpose of this study was to investigate the differences of knee concentric and eccentric strength and impact related knee biomechanics between jumpers and non-jumpers during step-off landing tasks. Ten male college swimming athletes (non-jumpers) and 10 track and volleyball athletes (jumpers) were recruited to participate in two test sessions: a muscle strength testing session of concentric and eccentric extension for dominant knee joint at 60 °/s and 180 °/s and a landing testing session. The participants performed five trials of step-off landing in each of four conditions: soft and stiff landing from 0.4 m and 0.6 m landing heights. The three-dimensional kinematics and ground reaction force were recorded simultaneously during step-off landing conditions. The results showed that the jumpers had significantly greater peak knee eccentric extension and concentric flexion torques compared to the non-jumpers. No significant group effects were found for peak vertical ground reaction force and knee range of motion during landing. The jumpers had significantly greater knee contact flexion angle, maximum knee flexion angle and initial knee extension moment compared to the non-jumpers. These results suggest that these athletes adopted a favorable impact attenuation strategy that is related to the greater knee eccentric muscle strength and training. 相似文献
214.
Behavioral Family Therapy (BFT) generally targets four typical disruptive behaviors among children ages from 2 to 7 years: noncompliance, aggression, tantrums, and negative talk. This study tests the effect of BFT on 20 Chinese aggressive children (16 boys and 4 girls) who were assigned to a BFT group or a control group. The results showed that the children's level of aggression in the BFT group reduced significantly compared to that of the control group, and the gains were maintained at a 6-month follow-up. These findings support the use of BFT as a treatment modality for Chinese aggressive children. 相似文献
215.
Two studies investigated whether one dimension of action–state orientation, namely, persistence-volatility, would moderate the effect of implementation intentions on goal progress. Results from Study 1 indicated that spontaneous implementation intentions predicted goal progress 2 weeks later only among participants who scored high on persistence. In Study 2, participants were randomly allocated to an implementation intentions group and a control group. Results indicated that persistence was positively associated with goal progress among participants in the implementation intentions group but not among those in the control group. Theoretical and practical implications of these findings were discussed. 相似文献
216.
Wei‐Bin Zhang 《World Futures: Journal of General Evolution》2013,69(4):209-223
The purpose of this study is to discuss the dynamic interdependence of knowledge and economic growth. We show that the traditional economics, which treats knowledge as parameters and is mainly developed within linearized, stable and static frameworks can hardly explain the modern economic complexity. We argue that it is necessary to treat creativity, learning and knowledge utilization as endogenous dynamic processes of social and economic evolution. To handle with the complicated dynamic interdependence of wealth and knowledge accumulation, we need to apply genuine nonlinear dynamic theory. In particular, we discuss possible benefits of government's intervention in education and science to the society when the social and economic evolution is characterized of nonlinearity, instability and multi‐equilibria. 相似文献
217.
ABSTRACTUsing faces as the priming stimuli, the present study explored the influence of facial expressions on the activation of gender stereotypes using a lexical decision paradigm. Experiment 1 explored the activation of gender stereotypes when the facial primes contained only gender information. The results showed that gender stereotypes were activated. In Experiment 2, the facial primes contained both gender category and expression information. The results indicated that gender stereotypes were not activated. Experiment 3 required the participants to make emotion, gender, or impression decisions concerning the facial primes before the lexical decision task. The results showed that gender stereotypes were not activated in emotion and impression decisions conditions, whereas stereotypes were activated in gender decisions condition. These finding suggest that facial expressions can inhibit automatic activation of gender stereotypes, unless the perceivers perform gender categorization processing to prime faces intentionally. 相似文献
218.
Janxin Leu Batja Mesquita Phoebe C. Ellsworth Zhang ZhiYong Yuan Huijuan Emma Buchtel 《Cognition & emotion》2013,27(3):419-435
Past research generally suggests that East Asians tolerate opposing feelings or dialectical emotions more than North Americans. We tested the idea that North Americans would have fewer opposing emotions than East Asians in positive, but not in negative or mixed situations. Forty-seven European American, 40 Chinese, and 121 Japanese students reported the emotions that a protagonist of standardised positive, negative, and mixed situations would feel. Emotions were coded into three valence categories: pleasant, unpleasant, and neither-pleasant-nor-unpleasant. As predicted, cultural differences in opposing emotion associations were found in positive situations only. Moreover, East Asians reported more neither-pleasant-nor-unpleasant feelings, especially in mixed situations, possibly reflecting a deferral of valence appraisal due to expected change. 相似文献
219.
Growth curve models with different types of distributions of random effects and of intraindividual measurement errors for robust analysis are compared. After demonstrating the influence of distribution specification on parameter estimation, 3 methods for diagnosing the distributions for both random effects and intraindividual measurement errors are proposed and evaluated. The methods include (a) distribution checking based on individual growth curve analysis; (b) distribution comparison based on Deviance Information Criterion, and (c) post hoc checking of degrees of freedom estimates for t distributions. The performance of the methods is compared through simulation studies. When the sample size is reasonably large, the method of post hoc checking of degrees of freedom estimates works best. A web interface is developed to ease the use of the 3 methods. Application of the 3 methods is illustrated through growth curve analysis of mathematical ability development using data on the Peabody Individual Achievement Test Mathematics assessment from the National Longitudinal Survey of Youth 1997 Cohort (Bureau of Labor Statistics, U.S. Department of Labor, 2005). 相似文献
220.
From a longitudinal study, we have repeatedly measured data from multiple individuals at multiple occasions. For each individual, the relation between 2 variables can be measured by the Pearson’s correlation. The question is how to aggregate the multiple correlations and conduct statistical inference on the aggregated intra-individual correlation. Several methods are proposed to aggregate and test intra-individual correlations: (a) a meta-analysis method based on Fisher’s Z transformed correlations, (b) a meta-analysis method based on the Pearson’s correlations, and (c) a multilevel modeling method using data standardized within each individual. The performance of the methods after bias corrections was compared using simulations with considering factors including numbers of individuals, numbers of time points, population effect sizes, and their distribution forms (homogeneous vs heterogeneous). The results from the simulation studies show that estimation biases were found using the meta-analytic methods and suggestions on when and how to correct biases were provided based on the simulation results. Furthermore, the performance of the 3 methods after necessary bias corrections was found to be comparable and reasonably good, indicating that all 3 methods worked for aggregating and testing intra-individual correlations. An empirical daily diary data set was then used to illustrate the applications of the 3 methods. The assumptions, advantages and disadvantages, and possible extensions of the 3 methods were discussed. 相似文献