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
Childhood characteristics are associated with life-course-persistent antisocial behavior in epidemiological studies in general population samples. The present study examines this association in an inpatient sample. The purpose is to identify easily measurable childhood characteristics that may guide choice of treatment for adolescent psychiatric inpatients with severe disruptive behavior. Patients (N?=?203) were divided into two groups with either early-onset (EO) or adolescent-onset (AO) disruptive behavior, based on ages at which professional care was used for disruptive behavior, referral to special education, and criminal offences. Both groups differed on several childhood characteristics. No gender differences in these characteristics were found. Logistic regression analysis indicated that individuals with grade retention in primary school, childhood impulsive behavior, and a history of physical abuse, had the highest probability of being member of the EO group. These characteristics are reasonably easy to identify, likely apply to other clinical samples as well, and may help clinicians to target their treatment. 相似文献
HIV-related stigma in African and Afro-Caribbean diaspora communities in the Netherlands was investigated. Interviews with HIV-positive and HIV-negative community members demonstrated that HIV-related stigma manifests as social distance, physical distance, words and silence. The psychological consequences of HIV-related stigma among those diagnosed with HIV reported were emotional pain, sadness, loneliness, anger, frustration and internalised stigma. The social consequences included decreased social network size, limited social support and social isolation, and resulted from not only enacted stigma but also self-imposed social withdrawal. Also, poor treatment adherence was a health-related consequence. People living with HIV employed both problem-focused and emotion-focused coping strategies to mitigate the negative consequences of stigma. Problem-focused coping strategies included selective disclosure, disengagement, affiliating with similar others, seeking social support and, to a lesser extent, activism. Emotion-focused strategies included distraction, positive reappraisal, religious coping, external attributions, disidentification and acceptance. HIV-related stigma clearly permeates African and Afro-Caribbean communities in the Netherlands, and should be targeted for intervention. 相似文献
Participants were presented with sentences mentioning an entity with a typical location in the upper or lower vertical space (e.g., roof vs. root). Sentences supported or reversed the typical location of the target entity. Sensibility judgments requiring upwards or downwards responses were faster when the response matched rather than mismatched the target entity's typical location. This compatibility effect was independent of whether the sentence context supported or reversed the target entity's typical location. The results, therefore, provide clear evidence for word-based but no evidence for sentence-based simulation processes. 相似文献
Past research has revealed significant relationships between organizational justice dimensions and job performance, and trust is thought to be one mediator of those relationships. However, trust has been positioned in justice theorizing in 2 different ways, either as an indicator of the depth of an exchange relationship or as a variable that reflects levels of work-related uncertainty. Moreover, trust scholars distinguish between multiple forms of trust, including affect- and cognition-based trust, and it remains unclear which form is most relevant to justice effects. To explore these issues, we built and tested a more comprehensive model of trust mediation in which procedural, interpersonal, and distributive justice predicted affect- and cognition-based trust, with those trust forms predicting both exchange- and uncertainty-based mechanisms. The results of a field study in a hospital system revealed that the trust variables did indeed mediate the relationships between the organizational justice dimensions and job performance, with affect-based trust driving exchange-based mediation and cognition-based trust driving uncertainty-based mediation. 相似文献
We question the plausibility of Fincher & Thornhill's (F&T's) argument that localised pathogen-host coevolution leads to out-groups having pathogens more damaging than those infecting one's own family or religious group. 相似文献
Self-esteem is defined as sense of self-worth and self-respect, being crucial for understanding people’s well-being and success. It is one of the most studied constructs in the social sciences, with the Rosenberg Self-Esteem Scale (RSES) being the most used measure. Across four studies (N = 1450), we tested the psychometric parameters of an abbreviated version of the RSES. Through Item Response Theory, the five best items were selected to form the unidimensional Brief Rosenberg Self-Esteem Scale (B-RSES), a reliable and valid measure of self-esteem, which is invariant across age groups and gender. In addition, both RSES and B-RSES correlated very similarly with the Big Five Personality Factors. Also, the B-RSES was strongly correlated with three other short measures of self-esteem, besides being more strongly associated with a range of variables such as conscientiousness and self-competence in comparison to the other three short scales. Together, the B-RSES is especially useful in research that requires rapid evaluation and the use of multiple variables.
Sex Roles - Three experiments (two pre-registered) tested whether gender collective narcissism (i.e., a belief that one’s gender ingroup’s exceptionality is not sufficiently recognized... 相似文献
Research on Child and Adolescent Psychopathology - This study is the first to distinguish two possible predictive directions between trauma exposure and executive functioning in children in a... 相似文献