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181.
Effect of contraction intensity [100%, 75%, 50%, and 25% maximum voluntary contraction (MVC)] and movement velocity [0 degrees (isometric)], 50 degrees, 100 degrees, 200 degrees, and 400 degrees/sec. [isovelocities]) on root mean square amplitude (SEMG-RMS) and median frequency power spectrum (SEMG-MNF) of vastus lateralis (VL) surface electromyography was investigated with ten healthy female university students. Peak torque (PT), mean torque (MT), SEMG-MNF, and SEMG-RMS, analyzed using separate repeated-measures analyses of variance (p < or = .05), indicated: (1) an inverse relation between PT and MT and movement velocity, (2) greater SEMG-MNF values during all isovelocity conditions compared with isometric conditions, with highest values occurring at 50 degrees /sec. and at 100% and 75% MVC, and (3) at all contraction intensities SEMG-RMS values were higher during dynamic movements than isometric movements and highest at 200 degrees /sec. Isovelocity contractions were inferred to facilitate a greater recruitment of fast-twitch fibers (via increased SEMG-MNF), which was intensified at 50 degrees /sec., whereas greater overall muscle activation was found at 200 degrees /sec.  相似文献   
182.
Artefacts are often regarded as being mere things that possess only instrumental value. In contrast, living entities (or some subset of them) are often regarded as possessing some form of intrinsic (or non-instrumental) value. Moreover, in some cases they are thought to possess such value precisely because they are natural (i.e., non-artefactual). However, living artefacts are certainly possible, and they may soon be actual. It is therefore necessary to consider whether such entities should be regarded as mere things (like most non-living artefacts) or as possessing intrinsic value (like many, if not all) living entities. That is, it is necessary to determine whether artefactualness is a value-relevant property with respect to the intrinsic value of living things.  相似文献   
183.
184.
This study investigated how early experience with racial discrimination affected the subsequent risky sexual behaviors of a diverse sample of African American youths (N = 745). The analyses focused on 3 risk-promoting factors thought to mediate the hypothesized discrimination → risky sex relation: negative affect, affiliation with deviant peers, and favorable attitudes toward risky sex. In addition, attentive parenting was examined as a protective factor. Analyses using structural equation modeling revealed that youths who perceived more racial discrimination at age 10 or 11 were engaging in more sexual risk taking at age 18 or 19. This relation was mediated by the hypothesized risk-promoting factors via pathways that were consistent with our conceptual model. Results also indicated a prospective reciprocal relation between parenting and children's deviant affiliations: deviant peer affiliations at age 10 or 11 predicted more attentive parenting behaviors by the parents; this response from the parents, in turn, predicted relatively fewer deviant affiliations when the youths were 15 or 16. Study findings are discussed in terms of their relevance to the disproportionately high rates of sexually transmitted infections among African Americans.  相似文献   
185.
What is more important: to provide citizens with more money or with more autonomy for their subjective well-being? In the current meta-analysis, the authors examined national levels of well-being on the basis of lack of psychological health, anxiety, and stress measures. Data are available for 63 countries, with a total sample of 420,599 individuals. Using a 3-level variance-known model, the authors found that individualism was a consistently better predictor than wealth, after controlling for measurement, sample, and temporal variations. Despite some emerging nonlinear trends and interactions between wealth and individualism, the overall pattern strongly suggests that greater individualism is consistently associated with more well-being. Wealth may influence well-being only via its effect on individualism. Implications of the findings for well-being research and applications are outlined.  相似文献   
186.
This study compared the social climate of peer‐run homes for recovering substance abusers called Oxford House (OH) to that of a staffed residential therapeutic community (TC). Residents of OHs (N = 70) and the TC (N = 62) completed the Community Oriented Programs Environment Scales. OHs structurally differ on two primary dimensions from TCs in that they tend to be smaller and are self‐run rather than professionally run. Findings indicated significantly higher Involvement, Support, Practical Orientation, Spontaneity, Autonomy, Order and Organization, and Program Clarity scores among the OH compared to TC residents. Additional analyses found the OH condition was higher Support, Personal Problem Orientation, and Order and Organization scores among women compared to men residents. These results suggested that these smaller OH self‐run environments created a more involving and supportive social milieu than a larger staff‐run TC. These findings are interpreted within Moos' ( 2007 ) four theoretical ingredients (i.e., social control, social learning, behavioral economics, and stress and coping), which help account for effective substance abuse treatment environments.  相似文献   
187.
The authors test predictions from climato-economic theories of culture that climate and wealth interact in their influence on psychological processes. Demanding climates (defined as colder than temperate and hotter than temperate climates) create potential threats for humans. If these demands can be met by available economic resources, individuals experience challenging opportunities for self-expression and personal growth and consequently will report lowest levels of ill-being. If threatening climatic demands cannot be met by resources, resulting levels of reported ill-being will be highest. These predictions are confirmed in nation-level means of health complaints, burnout, anxiety, and depression across 58 societies. Climate, wealth, and their interaction together account for 35% of the variation in overall subjective ill-being, even when controlling for known predictors of subjective well-being. Further investigations of the process suggest that cultural individualism does not mediate these effects, but subjective well-being may function as a mediator of the impact of ecological variables on ill-being.  相似文献   
188.
This study involved the translation, cultural adaptation and validation of the Athletic Coping Skills Inventory (ACSI-28) for a Spanish-speaking sport environment. The sample was made up of 1,253 Spanish athletes, 967 males and 286 females. Confirmatory factor analysis (CFA) showed that the 7-factor structure found in the English version was replicated in the Spanish translation in both males and females. Likewise, the reliability coefficients were similar to those of the English version, with values exceeding .80 for the total score. Several of the subscales correlated positively with sports experience and performance level. The Spanish version of the ACSI-28 thus maintains the factor structure of the original and exhibits similar psychometric properties. Consequently, it can reliably be applied to Spanish-speaking athletes for research and evaluation purposes.  相似文献   
189.
Safety in numbers is thought to be the principal advantage of living in groups for many species. The group can only provide protection against predators, however, when group cohesion is maintained. Vocalisations are used to monitor inter-individual distances, especially under conditions of poor visibility, but should be avoided in the presence of predators. Mentally tracking the movements of silent and invisible group members would allow animals foraging in dense vegetation to stay close to their group members while reducing the use of vocal contact. We tested the socio-spatial cognitive abilities of wild vervet monkeys (Chlorocebus pygerythrus) by comparing their reactions to plausible and implausible displacements of group members simulated by sound playbacks. Our methods are comparable to those used in studies of ‘object permanence’ and ‘invisible displacements’ of inanimate objects. Our results show that vervets can track the whereabouts of invisibly and silently moving group members, at least over short periods of time.  相似文献   
190.
Journal of Happiness Studies - Ancient philosophy proposed a wide range of possible approaches to life which may enhance well-being. Stoic philosophy has influenced various therapeutic traditions....  相似文献   
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