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941.
It is known that electromyostimulation (EMS) alone or superimposed over voluntary contraction (EV) can effectively improve muscle strength. However, the effect of this type of training on the ability to control force production at submaximal levels is unknown. The authors examined the effects of EV training on steadiness in force production of knee extensors and flexors in older adults. Forty participants, including 20 men and 20 women, 60-77 years of age, were randomly allocated into a control group (CG) and an electromyostimulation superimposed over voluntary contraction (EVG) group. The EVG performed 30 bilateral isometric knee extension and flexion contractions per session, 3 training sessions per week, for 6 weeks. The variations in force production, expressed in absolute (standard deviation [SD]) and relative (coefficient of variation [CV]) terms, were assessed in isometric contractions at 5%, 15% and 25% maximal voluntary contraction (MVC) levels. Results indicated that MVC increased in knee extension and flexion in EVG (p < .05) after the training; steadiness CV also improved at 15% MVC in knee flexion (p < .05) but no significant changes were found in knee extension and steadiness SD. The training-induced changes in MVC were not correlated to steadiness CV that might indicate different mechanisms underlying these adaptations. 相似文献
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944.
Handel RW Archer RP Elkins DE Mason JA Simonds-Bisbee EC 《Journal of personality assessment》2011,93(6):566-581
In this study, we evaluated the internal psychometric properties and external correlates of scores on the Clinical, Content, and Supplementary scales in a forensic sample of 496 adolescents (315 boys and 181 girls) who were court-ordered to receive psychological evaluations. We examined Cronbach's alpha coefficients, scale intercorrelation matrices, and frequencies of scale elevations. Further, we found varying degrees of support for the convergent and discriminant validity of scores on the MMPI-A (Butcher et al., 1992 ) Clinical, Content, and Supplementary scales. This study adds to the body of literature establishing the utility of the MMPI-A in forensic evaluations. 相似文献
945.
Individuals of all ages extract structure from the sequences of patterns they encounter in their environment, an ability that is at the very heart of cognition. Exactly what underlies this ability has been the subject of much debate over the years. A novel mechanism, implicit chunk recognition (ICR), is proposed for sequence segmentation and chunk extraction. The mechanism relies on the recognition of previously encountered subsequences (chunks) in the input rather than on the prediction of upcoming items in the input sequence. A connectionist autoassociator model of ICR, truncated recursive autoassociative chunk extractor (TRACX), is presented in which chunks are extracted by means of truncated recursion. The performance and robustness of the model is demonstrated in a series of 9 simulations of empirical data, covering a wide range of phenomena from the infant statistical learning and adult implicit learning literatures, as well as 2 simulations demonstrating the model's ability to generalize to new input and to develop internal representations whose structure reflects that of the items in the input sequence. TRACX outperforms PARSER (Perruchet & Vintner, 1998) and the simple recurrent network (SRN, Cleeremans & McClelland, 1991) in matching human sequence segmentation on existing data. A new study is presented exploring 8-month-olds' use of backward transitional probabilities to segment auditory sequences. 相似文献
946.
Preliminary data were collected to evaluate the performance of a social self-efficacy measure among 4,061 public high school adolescents. Principal-axis factor analysis was followed by a 4-way between-groups analysis of variance (ANOVA) to test for differences in the Total score means on selected demographic estimates and their interactions. Relations between the Total score and selected risk behaviors were examined through a series of one-way ANOVAs and the Tukey HSD test. Factor analysis results suggested a one-factor model best explained the factor structure of the scale items (factor loading range = .64 - .77, eigenvalue = 4.05, h(2) = .51). Females reported a significantly higher mean Total social self-efficacy rating than males, while White students reported a significantly higher mean Total social self-efficacy rating than Black and Asian students. Statistically significant lower mean Total social self-efficacy ratings were also noted for those who reported physical fighting, avoiding school, and being bullied. 相似文献
947.
Two studies are reported that investigate the applicability of prospect theory to college students' academic decision making. Exp. 1 failed to provide support for the risk-seeking portion of the fourfold pattern predicted by prospect theory but did find the greater weighting of losses over gains. Using a more sensitive dependent measure, in Exp. 2 the results of the first experiment were replicated in terms of the gain-loss effect and also found some support for the fourfold pattern in the interaction between probabilities and gain versus loss. The greatest risk-seeking was found in the high probability loss condition. 相似文献
948.
Cummins RA 《Psychological reports》2011,109(1):43-46
Researchers in the area of subjective wellbeing are now building on a body of research that spans more than three decades and includes many thousands of articles. It is time to move from exploratory studies to those based on accumulated psychometric understanding and theory. Two aspects of the article by Abdel-Khalek (2011) warrant attention from this perspective: the choice of scale and the issue of shared variance. 相似文献
949.
Mental fog is a core symptom of fibromyalgia. Its definition and measurement are central to an understanding of fibromyalgia-related cognitive disability. The Mental Clutter Scale was designed to measure mental fogginess. In an exploratory factor analysis of two different samples (n=128 and n=170), cognitive symptoms of fibromyalgia loaded on 2 dimensions: cognition and mental clarity. The mental clarity factor comprised 8 items with factor loadings greater than .60 and was named the Mental Clutter Scale. The factor stability of the new scale was good, internal consistency was .95, and test-retest reliability over a median of 5 days was .92. The 8-item scale is a quick measure of mental fog that provides clinicians with information about cognitive functioning in fibromyalgia. 相似文献
950.