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441.
    
The aim of the present randomized double‐blind placebo control trial was to investigate if vitamin D supplementation had an effect on vitamin D status, executive functioning and self‐perceived mental health in a group of Norwegian adolescents during winter time. Fifty adolescents were randomly assigned into an intervention group (vitamin D pearls) or a control group (placebo pearls). Before (pre‐test in December/January) and after (post‐test in April/May) the intervention period the participants were exposed to a test procedure, consisting of blood draw, completion of cognitive tests (Tower of Hanoi and Tower of London), and the Youth Self‐report version of the Child Behavior Checklist. Multivariate data analysis showed that participants with low vitamin D status scored worse on the Tower of London tests and the more difficult sub‐tasks on the Tower of Hanoi tests. They also had a tendency to report higher frequency of externalizing behavior problems and attention deficit. At pre‐test, the overall mean vitamin D status measured as 25‐hydroxy vitamin D was 42 nmol/L, defining deficiency (Intervention group = 44 nmol/L, Control group = 39 nmol/L). However, vitamin D supplementation caused a significant increase in vitamin D status resulting in a sufficient level in the Intervention group at post‐test (mean 62 nmol/L). The results also revealed that the intervention group improved their performance on the most demanding sub‐tasks on the ToH. Overall, the study indicates that vitamin D status in adolescents may be important for both executive functioning and mental health.  相似文献   
442.
    
Detachment from work during non-work time is generally related to a decrease in work-related strain. However, it might also hamper employees’ generation of new and useful ideas about work by completely shutting off work-related thoughts and/or feelings outside of work. In this day-level study, we used a within-person design to investigate the role of cognitive and emotional detachment from work during non-work time in relation to equivalent types of job demands and job resources, in the prediction of employee creativity. Cognitive detachment from work refers to mentally disconnecting from work and no longer thinking about job-related issues, whereas emotional detachment from work refers to affectively disconnecting from work and no longer experiencing job-related emotions. Survey data were gathered over the course of eight consecutive days from 151 health care employees. Multi-level analyses revealed that: (1) cognitive detachment was positively related to creativity, irrespective of the level of cognitive job demands and resources; (2) high emotional job demands in combination with either low levels of emotional detachment or high levels of emotional job resources were positively related to creativity. This day-level study provides insight into the relation between detachment from work and creativity from a process perspective, by showing specific conditions under which different types of detachment from work benefit employee creativity.  相似文献   
443.
The present study addressed the following questions: (a) To what extent do different methods of measuring the family environment converge onto a single latent construct? (b) How are the constructs of positive and of negative family environment related? (c) Do the associations among various methods of measuring the family environment differ as a function of children's gender or of risk? and (d) How are the latent constructs of family environment related to depression in mothers and their children? Participants were 240 children (mean age = 11.86 years, SD = 0.57) and their mothers, who varied with regard to their history of depression. Family environment was measured with self-report questionnaires completed separately by mothers and by children, observations of mother-child interactions, and a 5-min speech sample of each mother talking about her child. Confirmatory factor analyses revealed that different methods for assessment of the family environment converged and that the constructs of positive and of negative family environments were significantly related to each other and to depression in both mothers and their children. These findings may help inform future intervention efforts by highlighting specific parenting dimensions that are strongly associated with maternal and with child depression.  相似文献   
444.
In this paper, we investigate the user’s reactions to received suggestion by an Embodied Conversational Agent playing the role of artificial therapist in the healthy eating domain. Specifically, we analyse the behaviour of people who voluntarily requested to receive information from the agent, and we compare it with the results of a previous evaluation experiment in which subjects were not properly motivated to interact with the agent because they were selected for evaluating the system. This study is part of an ongoing research aimed at developing an intelligent virtual agent that applies natural argumentation techniques to persuade the users to improve their eating habits.  相似文献   
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The serial pattern found for conjunction visual-search tasks has been attributed to covert attentional shifts, even though the possible contributions of target location have not been considered. To investigate the effect of target location on orientation × color conjunction searches, the target’s duration and its position in the display were manipulated. The display was present either until observers responded (Experiment 1), for 104 msec (Experiment 2), or for 62 msec (Experiment 3). Target eccentricity critically affected performance: A pronounced eccentricity effect was very similar for all three experiments; as eccentricity increased, reaction times and errors increased gradually. Furthermore, the set-size effect became more pronounced as target eccentricity increased, and the extent of the eccentricity effect increased for larger set sizes. In addition, according to stepwise regressions, target eccentricity as well as its interaction with set size were good predictors of performance. We suggest that these findings could be explained by spatial-resolution and lateral-inhibition factors. The serial self-terminating hypothesis for orientation × color conjunction searches was evaluated and rejected. We compared the eccentricity effect as well as the extent of the orientation asymmetry in these three conjunction experiments with those found in feature experiments (Carrasco & Katz, 1992). The roles of eye movements, spatial resolution, and covert attention in the eccentricity effect, as well as their implications, are discussed.  相似文献   
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Gianakos  Irene 《Sex roles》2000,42(11-12):1059-1079
Sex Roles - The influence of gender roles on coping with workplace stressors was examined among 176 adult undergraduate students (130 females, 46 males) who were concurrently employed while...  相似文献   
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The aim of this study was to examine the role of family dimensions in tobacco, alcohol, and cannabis use among adolescents. Furthermore, we investigated how demographic variables (adolescents’ gender and age) influence substance use and moderate the relationship between family dimensions and substance use. The sample consisted of 14,825 adolescents aged 13–14, 15–16, and 17–18 who participated in the 2006 edition of the Health Behaviour in School-aged Children (HBSC) study in Spain. The HBSC-2006 questionnaire included demographic variables (gender and age), substance use variables (tobacco, alcohol, and cannabis use), and family dimensions (parental affection, parental promotion of autonomy, family activities, adolescent disclosure, parental solicitation, and parental knowledge). The results indicated that adolescent disclosure, family activities, and parental knowledge had a significant effect on substance use. Specifically, maternal variables were shown to be slightly more relevant than paternal variables. Additionally, substance use was higher in older adolescents than in younger adolescents, and boys smoked less than girls. The discussion focused on how family dimensions promoted responsible substance use in adolescence.  相似文献   
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