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901.
Delta (1–4 Hz) EEG power in non-rapid eye movement (NREM) sleep declines massively during adolescence. This observation stimulated the hypothesis that during adolescence the human brain undergoes an extensive reorganization driven by synaptic elimination. The parallel declines in synaptic density, delta wave amplitude and cortical metabolic rate during adolescence further support this model. These late brain changes probably represent the final ontogenetic manifestation of nature’s strategy for constructing nervous systems: an initial overproduction of neural elements followed by elimination. Errors in adolescent brain reorganization may cause mental illness; this could explain the typical age of onset of schizophrenia. Longitudinal studies of sleep EEG are enhancing our knowledge of adolescent brain maturation. Our longitudinal study of sleep EEG changes in adolescence showed that delta power, which may reflect frontal cortex maturation, begins its decline between ages 11 and 12 years and falls by 65% by age 17 years. In contrast, NREM theta power begins its decline much earlier. Delta and theta EEG frequencies are important to sleep theory because they behave homeostatically. Surprisingly, these brain changes are unrelated to pubertal maturation but are strongly linked to age. In addition to these (and other) maturational EEG changes, sleep schedules in adolescence change in response to a complex interaction of circadian, social and other influences. Our data demonstrate that the daytime sleepiness that emerges in adolescence is related to the decline in NREM delta as well as to altered sleep schedules. These longitudinal sleep data provide guideposts for studying cognitive and behavioral correlates of adolescent brain reorganization.  相似文献   
902.
The reported study measured the ratio between aperture‐width and hip‐width that marked the critical transition from frontal walking to body rotation for male and female participants. Half of the participants of each sex wore form‐fitting lycra clothes and half loose‐fitting jogging suits. Participants wearing the form‐fitting clothing reported heightened body awareness relative to those wearing the loose‐fitting clothing. For male participants this difference was reflected in a smaller aperture‐to‐hip ratio in the form‐fitting than loose‐fitting clothing condition. That is, males walked frontally through smaller apertures when wearing form‐fitting than when wearing loose‐fitting clothing. For females there was no difference in walking action as a function of clothing style. Results are discussed in terms of the perception of action opportunities in the environment, the influence of body awareness on such perception and sex differences. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
903.
We describe here a new test for dispositional optimism and pessimism in young children, the Parent‐rated Life Orientation Test of children (the PLOT) and assess its psychometric properties. Two hundred and twenty one mother–father pairs rated their children's (mean age = 8.1, SD = 0.3 years) dispositional optimism and pessimism using a new scale, the PLOT, including four optimism and four pessimism items. We associated the PLOT with parent‐rated self‐esteem (Behavioral Rating Scale of Presented Self‐Esteem in Young Children), social competence (Social Competence and Behaviour Evaluation Scale, the SCBE‐30), psychiatric symptoms (Child Behaviour Checklist, the CBCL) and temperament (Children's Behaviour Questionnaire, the CBQ) of the child. A confirmatory factor analysis (CFA) of the mother‐ and father‐rated PLOT revealed a significantly better fit for a two‐ over a one‐factor solution (p < 0.001). The optimism and pessimism subscales displayed good reliabilities, inter‐parental agreement and modest to moderate associations, in the expected direction, with the measures of self‐esteem, social competence, temperament and behaviour problems. To conclude, the PLOT shows good construct and convergent validity and reliability. The findings encourage its use to assess early emerging generalized expectancies of positive and negative outcomes in young children. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
904.
Using an international dataset of about 35 000 subjects, this paper provides an empirical example of high‐stakes incentives in relation to religious practice. First, we show that incentives (based on absolute belief) play a salient role in religious performance. Second, we find that when both positive (heaven) and negative (hell) incentives are available the former are more effective than the latter. Specifically, it is shown that beliefs in heaven are much more relevant than beliefs in hell when estimating the production of religious commodities (church‐attendance and praying equations). Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
905.
The aim of this study was to analyse the impact of the effort–reward imbalance (ERI) model on intent to leave the current organization (ITL organization) and intent to leave the nursing profession (ITL profession) in a prospective way. A total of 1,531 health care workers who remained in their job filled in a self‐administered questionnaire at baseline and 1 year later. ERI was measured at baseline by a 23‐item questionnaire. Multivariate logistic regression analyses were performed. Within a population with low intent to leave at baseline, we found that an imbalance between high efforts and low rewards (extrinsic hypothesis) increased the risk of high ITL organization (OR 4.98; 95% CI 2.07–11.97) and high ITL profession (OR 1.84; 95% CI 1.03–3.30), 1 year later. A high level of overcommitment (OC; intrinsic hypothesis) was not predictive for both intent to leave outcome variables, neither was the interaction between high efforts/low rewards and a high level of OC (interaction hypothesis). Our results showed that a perceived effort‐reward imbalance (ERI) at work is a significant predictor of intent to leave among health care workers. This contribution concludes with some directions aimed at boosting nurses' retention and recommendations for future research.  相似文献   
906.
907.
Multiple‐choice response formats are troublesome, as an item is often scored as solved simply because the examinee may be lucky at guessing the correct option. Instead of pertinent Item Response Theory models, which take guessing effects into account, this paper considers a psycho‐technological approach to re‐conceptualizing multiple‐choice response formats. The free‐response format is compared with two different multiple‐choice formats: a traditional format with a single correct response option and five distractors (‘1 of 6’), and another with five response options, three of them being distractors and two of them being correct (‘2 of 5’). For the latter format, an item is scored as mastered only if both correct response options and none of the distractors are marked. After the exclusion of a few items, the Rasch model analyses revealed appropriate fit for 188 items altogether. The resulting item‐difficulty parameters were used for comparison. The multiple‐choice format ‘1 of 6’ differs significantly from the multiple‐choice format ‘2 of 5’, while the latter does not differ significantly from the free‐response format. The lower difficulty of items ‘1 of 6’ suggests guessing effects.  相似文献   
908.
This paper investigated whether interpersonal relationship orientation, as measured by the Fundamental Interpersonal Relationship Orientations‐Behaviour (FIRO‐B), predicts ratings of leadership capability and managerial level of attainment. In all, 547 participants reported their managerial level in their organization, and were rated by trained consultants on their leadership capability. Results showed that several scores on the FIRO‐B positively predicted ratings of leadership capability and managerial level reached even after controlling for the effect of intelligence and demographic variables. This study provides some initial evidence for the validity of the FIRO‐B in the prediction of perceptual and objective measures of leadership capability. Implications for selection and assessment are discussed.  相似文献   
909.
This paper discusses a qualitative study that explores the impact the development of a cultural contact zone has upon identity processes in the Dialogical Self. The analysis draws upon interviews with Irish nationals, immigrants and asylum seekers in a new cultural contact zone. The findings illustrate uncertainty experienced as a result of immigration, suggesting that the development of the contact zone caused cultural discontinuity. The individuals' uncertainty for their cultural identities' future viability demanded the development of identity strategies to maintain continuity with their perceived cultural future, where they were faced with cultural others. Identity repositionings and a strategy to maintain continuity will be explored in the current paper. The Irish and asylum seeker participants' unprompted focus on schooling will be explored as a continuity strategy. The participants constructed schooling as a tool for the ‘cultural correction’ of migrant children and a means for the assimilation of migrants into the Irish community. The paper discusses the function of this strategy for the two groups, and the theoretical integration of cultural level processes in the theory of the Dialogical Self. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
910.
Given the polarization of the early 21st century political atmosphere in the U.S., intergroup dialogue has emerged as a unique alternative setting, with intentions of facilitating a more productive and thoughtful citizen engagement. Although cross‐partisan dialogue efforts are underway in community contexts, they have been slower to reach academic settings. This paper is an exploratory study of our own liberal‐conservative dialogue course at the University of Illinois–the first of its kind, to our knowledge. After describing basic features of the course, we identify themes from student journals and final evaluations suggesting both dialogue benefits and challenges. Finally, we discuss the growing literature around dialogue, questions of its long‐term impact, and larger potential barriers to participation in liberal‐conservative dialogue, specifically. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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