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971.
Cognitive complaints are common among subjects with fibromyalgia (FM). Yet, few studies have been able to document these deficits with cognitive tasks. A main limitation of existing studies is that attention has been broadly defined and the tasks used to measure attention are not designed to cover all the main components of the attentional system. Research on attention has identified three primary functions of attention, known as alerting, orienting and executive functioning. This study used the attentional network test-interactions task to explore whether and which of the three attentional networks are altered in FM. Results showed that FM patients have impaired executive control (greater interference), reduced vigilance (slower overall reaction time) and greater alertness (higher reduction in errors after a warning cue). Vigilance and alertness showed several relations with depression, anxiety and sleep quality. Sleep dysfunction was a significant predictor for alertness, whereas there were no significant predictors for vigilance. These findings highlight that the treatment of sleep difficulties in FM patients may help with some of their cognitive complaints.  相似文献   
972.
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   
973.
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   
974.
Psychosocial correlates of alexithymia were examined in 102 healthy, older adults (ages 53-83; 76% male). Alexithymic ( n = 26) and non-alexithymic ( n = 30) groups, defined by top ( S 70) and bottom ( h 54) quartiles of the distribution of Toronto Alexithymia Scale (26-item) scores, were compared with respect to psychosocial, psychophysiological, and biomedical risk factors for cardiovascular disease. Both categorical ratings and continuous scores of alexithymia were associated with significantly greater levels of trait anxiety, anger-in, neuroticism, hostility, perceived stress, depression, and lower levels of social support. Compared to non-alexithymics, alexithymics displayed significantly greater blood pressure responses to anger provocation and tended to have a greater percent body fat. The groups did not differ in resting cardiovascular parameters, heart rate reactivity, fasting glucose and lipoprotein lipids, body mass index, waist-to-hip ratio, social desirability, or trait anger. These findings suggest several psychosocial and psychophysiological pathways by which alexithymia may confer risk for cardiovascular disease among older adults.  相似文献   
975.
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   
976.
The aim of this study was to test the hypothesis that developmental differences exist in the use of learning strategies in primary school children. Serial and subjective clustering in a multitrial Pictorial Verbal Learning Test (PVLT) were compared in 79 children aged 6–12. Correlation analyses indicated that serial clustering yielded better performance when information was presented on the initial trials of the test. Subjective clustering was superior when information was presented repeatedly, i.e., after three or more trials. Analyses of variance indicated that subjective clustering was used more often in older children with repeated presentations. On the other hand, there was no increase in the use of serial clustering with age and with repeated presentations. The findings imply that training in the use of proper strategies could have benefit for children who use an inefficient learning strategy and/or have a learning problem. In addition, they point to the importance of the factor “age” in relation to the way information is presented to children.  相似文献   
977.
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   
978.
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   
979.
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   
980.

The fracture surface energy is calculated for a one-dimensional, exactly solvable model of a crack. The temperature dependence of the crack surface tension is determined on the basis of a self-consistent Einstein approach. It is found that lattice vibrations result in a strong reduction in the crack surface tension.  相似文献   
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