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81.
This study used a dual task with participants of different levels of cognitive capacities, assessed with neuropsychological tests, to examine the attentional cost on time judgment of processing concurrent temporal and non-temporal information. Children and adults performed a temporal reproduction task with either an interfering temporal or non-temporal discrimination task. The results showed an underestimation of time in the dual task compared to the single task, the extent of which was directly linked to individual attentional capacities. However, the non-temporal task interfered more than the temporal task on the reproduced durations. Nonetheless, the temporal reproduction task equally affected performance in the non-temporal and the temporal discrimination task. These results reveal the predominant role of the cost of dual-tasking in interference effects on time judgment, and the lesser role of concurrent information, especially of temporal information. This suggests a lack of competition for attentional resources in the processing of multiple durations.  相似文献   
82.
Much previous research has examined various aspects of auditory processing, including the localization of sounds, and the influence of lexical and indexical information on language processing. In the present set of experiments we explored the ability of listeners to estimate the number of speakers in a group solely from the information in an auditory signal. The bound on accurately estimating the number of simultaneous speakers is 3. We suggest that subitization—the ability to estimate numerosity of visual and auditory elements without explicitly counting these elements—rather than the capacity of short-term memory, may underlie this limitation. The cognitive constraint on estimating the number of simultaneous speakers may have implications for a wide variety of seemingly unrelated psychological phenomena.  相似文献   
83.
The θ′′-Al3Cu phase plays an important role in the precipitation process of Al–Cu alloys. This phase has a sandwich structure—every two {200}Cu layers are separated by three {200}Al layers. To analyse the formation mechanism of this structure, the elastic strain energy of the {200}Cu and {200}Al layers, and the chemical bonding energy that reflects the interaction between the electrons in Cu and neighbouring Al atoms are calculated and analysed by first-principles calculations, projected density of states and Bader analysis. Our computation results reveal that this sandwich structure is energetically preferred in the competition of elastic strain and chemical bonding energies. To minimise the elastic strain energy of {200}Al and {200}Cu layers, the {200}Cu layers prefer being apart from each other, whereas the chemical bonding energy favours the opposite arrangement because the intermetallic bond between Al and Cu atoms may form through p-d hybridization.  相似文献   
84.
Asthma remains the most prevalent chronic illness among children. Despite the substantial body of literature examining children with asthma, few studies have examined parents’ perspectives of the condition and experiences of caregiver stress. Parents of children with chronic illnesses experience elevated stress and may have limited opportunities to cope with complex emotions while caring for children with asthma. Drawing from focus groups and interviews with African American and Hispanic parents of children with asthma, this qualitative study was conducted as part of a patient-centered engagement process to inform the refinement of an intervention aimed at reducing stress among parents of children with asthma. All data were transcribed and underwent three waves of inductive analysis. The content analysis indicated that the unpredictable nature of asthma and the caregiving burden associated with managing children’s asthma contributed to parents’ stress, and external contexts compounded the impact of these stressors. Parents also reported having difficulty identifying how they coped with stress and employed approaches to coping with stress that they applied intermittently but encountered several barriers to enacting known or available coping strategies. Analyses also revealed that parents desired a multimodal stress reduction intervention that emphasized building relationships, allowed for flexibility, and encouraged staff-parent communication. Whereas African American and Hispanic parents’ experiences of stress and coping strategies were similar, their preferences differed in regards to incorporating technology into the intervention, the credentials of facilitators, and the salience of language preferences. Understanding the complexities of stressors facing caregivers is important for developing interventions to support parents and children coping with asthma, and in particular when working with families from diverse backgrounds.  相似文献   
85.
Young children develop social and emotional competence through interactions with others in the two major contexts in which they spend time: home and preschool. This study examined whether parenting stress in the home context is related to the children's behaviour while in preschool. Previous research has suggested that parenting stress negatively influences parenting behaviour, which in turn has been shown to impact children's development. This study examined the direct relationship between parenting stress and children's behaviour in two types of preschool programmes: private day care centres and Head Start. Parenting stress was significantly related to teacher ratings of social competence, internalizing behaviours, and externalizing behaviours, and the effects of parenting behaviour do not appear to mediate this relationship. Parenting stress was most strongly related to children's social competence. Parents' reports of expectations for their child's behaviour appear to weakly moderate the relationship between externalizing behaviour and parenting stress. This study suggests that examination of a parent's level of stress, in addition to parenting practices, may be important in research and interventions with preschool children's behaviour and social competence. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
86.
The School Reinforcement Survey Schedule (SRSS) was administered to 2,828 boys and girls in middle schools in the United States and an Italian translation was administered to 342 boys and girls in middle schools in Northern Italy. An exploratory factor analysis using half the American data set was performed using maximum likelihood estimation with a promax rotation. This analysis produced a structural equation model with six interpretable latent variables. This analysis was confirmed by results demonstrating a good fit with the other half of the American sample and separately with the Italian sample. Scores for the six latent variables were constructed and information about the distribution of scores was obtained. Multiple comparisons of the means were performed by gender, within each national sample, for each of the six latent variables. American and Italian girls report obtaining greater enjoyment from a wider variety of school activities compared to American and Italian boys.  相似文献   
87.
Two studies of ethnically diverse US college students from northern California examined whether ingroup bias and gender norm violations influence acquaintance rape attributions (Study 1, N?=?118; Study 2, N?=?140). Participants read vignettes depicting acquaintance rape and completed questionnaires. Victims were part of participants’ ingroup or outgroup. Study 1 manipulated the victim’s sexual history (chaste or promiscuous). Study 2 manipulated the victim’s alcohol use (sober or intoxicated). Ingroup victims were perceived more positively than outgroup victims if the victims were promiscuous or intoxicated. More guilt was attributed to rapists of ingroup victims than outgroup victims if the victims were promiscuous or intoxicated. Findings are examined in relation to ingroup bias and gender norm violations.  相似文献   
88.
As part of a longitudinal study, the Cognitive Triad Inventory for Children (CTI-C; N. J. Kaslow, K. D. Stark, B. Printz, R. Livingston, & S. L. Tsai, 1992) as well as other measures of cognitive style and depressive symptoms were administered annually to 3 cohorts of children starting in Grades 2, 4, and 6. Developmentally based analyses revealed 4 things: (a) The factor structure of the CTI-C changed over the course of middle childhood and then stabilized in early adolescence; (b) the CTI-C correlated significantly with measures of depression, self-perceived competence, self-worth, perceived controllability, and perceived contingency, but not with measures of attributional style; (c) 1-year stability correlations increased substantially from Grade 2 to Grade 8; and (d) the CTI-C did not generally predict self-reported depressive symptoms 1 year later. Implications emerge regarding developmental changes in the structure of children's depressive cognitions.  相似文献   
89.
对建立我国艾滋病防治督导与评估体系的思考   总被引:1,自引:0,他引:1  
随着我国艾滋病防治工作的持续深入,定期对艾滋病防治工作进行督导与评估越来越重要。但是,到目前为止,我国尚未建立国家综合协调的艾滋病防治督导与评估体系。通过对建立国家艾滋病防治督导评估体系的必要性、可行性及存在的问题进行分析,围绕如何构建一个统一、综合、有效的督导评估体系提出政策建议。  相似文献   
90.
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