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271.
Abstract

The present study was designed to examine the effect of information about the high prevalence of safe sex on condom use intention, and to investigate the possible mediating role of the perceived social norm of friends, and the perceived social norm of future. sexual partners. Participants were provided with gender specific prevalence information, that is with the information that most men have exclusively safe sex, or with the information that most women exclusively engage in safe sexual behavior. The results show some gender differences. Information about the high prevalence of safe sex among men tends to increase women's condom use intention, and this effect seems to be mediated by the paceived social norm of future sexual partners. Men's intention, on the other hand, seems to be unaffected by high prevalence information of safe sex. Implications for research and prevention are discussed  相似文献   
272.
Abstract

The present paper replicates and extends previous studies on the psychometric properties of the Pediatric Oncology Quality of Life Scale (POQOLS). The research questions were focused on (a) internal consistency; (b) relation with demographics; and (c) ability to discriminate between patient groups. Data were gathered in a Dutch-speaking Belgian sample of 73 pediatric oncology patients, drawn from the population of a university hospital. The parents completed the POQOLS, a 21-item parent-report inventory for the assessment of physical restriction, emotional distress and discomfort from medical treatment in pediatric oncology patients. The results support the psychometric quality of the POQOLS. Three of the core aspects of quality of life are tapped using sufficiently short and internally consistent subscales. The instrument is free from relations with demographics and shows good discriminant ability to differentiate between patient groups according to time since diagnosis, treatment status and diagnosis.  相似文献   
273.
Research on anxiety and depression after fall-related injuries to the extremities and its pre-fall determinants is scarce. The present study sought to examine change between pre-fall and post-fall anxiety and depression and its (pre-fall) predictors. Data were obtained from 181 Dutch persons, aged 57 and older, who sustained fall-related injuries between 1993 and 1997. Demographic (e.g. socio-economic status), health-related (e.g. number of chronic conditions), and psychosocial (e.g. social support, neuroticism) factors were determined in 1993 (prior to the fall). Depressive symptoms and anxiety were determined prior to the fall, and two, five and twelve months after the fall. Taking into account pre-fall anxiety and depression, pre-fall neuroticism was the most consistent, independent predictor of adverse changes in anxiety and depression. Other factors, including severity of the fall and age were not related to changes in anxiety and depression. Our prospective findings may be interpreted as support for the importance of personality for mental health outcomes in persons who have sustained fall-related injuries.  相似文献   
274.
The aim of this study was to investigate interference control in adolescents with Mild to Borderline Intellectual Disability (MBID) by addressing two key questions. First, as MBID is often associated with comorbid behavior disorders (BD), we investigated whether MBID and BD both affect interference control. Second, we studied whether interference control deficits are associated to problems in everyday executive functioning. Four groups of adolescents with and without MBID and/or BD performed the Eriksen flanker task, requiring participants to respond to a central target while ignoring interfering flanking stimuli. Their teachers rated behavior on the Behavior Rating Inventory Executive Function (BRIEF). We found pronounced effects of MBID but not BD on flanker interference control. In contrast, we observed pronounced effects of BD, but not MBID, on the BRIEF. In addition, flanker interference scores and BRIEF scores did not correlate. These results are taken to suggest that adolescents with MBID are characterized by deficits in interference control that do not become manifest in ratings of everyday executive functioning. In contrast, adolescents with BD are not characterized by deficits in interference control but do show elevated ratings of deficits in everyday executive function.  相似文献   
275.
Studies on adults have revealed a disadvantageous effect of negative emotional stimuli on executive functions (EF), and it is suggested that this effect is amplified in children. The present study’s aim was to assess how emotional facial expressions affected working memory in 9- to 12-year-olds, using a working memory task with emotional facial expressions as stimuli. Additionally, we explored how degree of internalizing and externalizing symptoms in typically developing children was related to performance on the same task. Before employing the working memory task with emotional facial expressions as stimuli, an independent sample of 9- to 12-year-olds was asked to recognize the facial expressions intended to serve as stimuli for the working memory task and to rate the facial expressions on the degree to which the emotion was expressed and for arousal to obtain a baseline for how children during this age recognize and react to facial expressions. The first study revealed that children rated the facial expressions with similar intensity and arousal across age. When employing the working memory task with facial expressions, results revealed that negatively valenced expressions impaired working memory more than neutral and positively valenced expressions. The ability to successfully complete the working memory task increased between 9 to 12 years of age. Children’s total problems were associated with poorer performance on the working memory task with facial expressions. Results on the effect of emotion on working memory are discussed in light of recent models and empirical findings on how emotional information might interact and interfere with cognitive processes such as working memory.  相似文献   
276.
Structural modulations hosted by complex oxides are–beyond relative orientation changes of ‘rigid units’–accompanied by characteristic distortions of coordination polyhedra. Electronic structure calculations in the local density approximation, performed at model clusters derived from positionally modulated structures, proved that the molecular–orbital structure also sensitively reflects such distortions. The latter crystal-field splitting of unoccupied states is accessible by high-resolution electron energy-loss near-edge structure (ELNES) spectroscopy. However, since ELNES spectra average over many different individual target-ion environments, the resulting ELNES possesses significantly broadened spectral features. In this contribution, such broadening is shown to dramatically influence the spectral shape of the Ti-L 2,3 ELNES acquired at the strongly modulated fresnoite framework compound Sr2TiSi2O8.  相似文献   
277.
High-resolution annular dark field imaging has been used to study small precipitates in the Al matrix of 6XXX-series aluminium alloys. Cu-containing columns in precipitates were imaged by atomic number contrast along a 〈100〉 matrix direction. At an under-aged condition, large, lath-shaped particles of the Cu-containing Q′-phase were observed at grain boundaries. At over-aged conditions, Q′ was the main matrix phase. In both cases the laths showed an Al {150} habit plane. A precursor phase was found, with different arrangement of Cu-rich columns from that of the Q′-phase and sharing Al {100} habit planes. Precipitates containing elements of both the Q′-phase and the precursor were found to be common. Annular dark field imaging can differentiate directly between phases. The method complements and aids interpretation of conventional high-resolution TEM images and nano beam diffraction observations. The results obtained contribute to an improved understanding of the crystallography of the precursor and details of the structural transformation taking place during the precipitation process.  相似文献   
278.
The devitrification process of Zr46.75Ti8.25Cu7.5Ni10Be27.5 metallic glass during annealing in the supercooled liquid region has been studied by conventional, high-resolution and analytical transmission electron microscopy (TEM). Two kinds of particle appear during devitrification: quasicrystals and crystalline precipitates. Nanoanalysis with energy-dispersive X-ray spectroscopy and electron energy-loss spectroscopy reveal that quasicrystals are Be free, while the crystallites have the ZrBe2 hexagonal structure. These experiments confirm the key role of Be during devitrification. They also indicate that quasicrystals can form in the system Zr–Ti–Cu–Ni (without Be), as further evidenced by direct synthesis and an in situ neutron diffraction investigation, according to the chemical composition deduced from the TEM analysis.  相似文献   
279.
Human sensitivity for social cues is exquisite, as illustrated by the ease with which simplified point-light movements invoke social and emotional responses. Compared to faces, these biological motion stimuli only recently started to be used to explore questions regarding social cognition and anxiety. We presented human point-light walkers that could be perceived as facing towards or facing away from the observer, and tested whether participants with high social anxiety would perceive these bistable stimuli differently, because this type of stimuli has particular relevance for them. The results showed that observers with high social anxiety tended to see walkers as facing away more frequently than those with low social anxiety. This may mean that high socially anxious observers are biased towards the more positive perceptual alternative because they are motivated to protect themselves against threatening social experiences, but we also explore alternative explanations. The findings are in line with the evidence for a positivity bias in perception, also called wishful seeing, but in contrast with the attentional negativity bias often found in social anxiety. We discuss reasons for this divergence and possible limitations of the current study.  相似文献   
280.
This study explores the notion of children's agency in situations of extreme adversity. The child participants (n=117) live in the midst of the HIV/AIDS pandemic; extreme poverty; and systemic educational malfunction. Four focus group interviews were conducted with the children to explore their experiences of potential barriers to education. The findings indicated that contextual factors had a profoundly negative impact on the children, with their agentive capacity being severely compromised through their exposure to multiple, complex layers of risk. There was very little evidence to suggest that children retain any sense of their own agency in such adversity. This has implications for their resilience and for the development of policy and intervention strategies that may meet these children's needs.  相似文献   
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