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261.

The microstructure and crystallization behaviour of melt-spun Al88Ni9Ce2Fe1 amorphous alloy and nanophase composites have been studied by means of X-ray diffraction, transmission electron microscopy and scanning and isothermal calorimetry. The diffraction patterns from Al88Ni9Ce2Fe1 amorphous alloys are diffuse, indicating a basically amorphous structure but contain two rings presumed to be associated with quenched-in nuclei. In the cases of Al88Ni9Ce2Fe1 nanophase composites, nanoscale precipitated particles are homogeneously dispersed in an amorphous matrix, and the crystallite diameter and volume fraction are sensitive to quenching conditions. During thermal crystallization, a two-step phase transformation occurs in the amorphous alloy and nanocomposites, which is characterized by a diffusion-controlled precipitation of nanoscale Al particles and the growth of a Al3(Ni, Fe) nanophase prior to a Al11Ce3 nanophase. This study gives insight into structure-control for obtaining nanophases dispersed in an amorphous matrix by rapid quenching.  相似文献   
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ObjectivesThe present study is a review on studies about the relationships between the three basic psychological needs/motivational regulations (i.e., amotivation, controlled regulation, extrinsic autonomous regulation, and intrinsic motivation) and burnout.DesignA systematic review and meta-analysis.MethodStudies were identified through five electronic databases and manual search using combinations of three groups of keywords. Three inclusion criteria were then used to screen the searched articles.ResultsEighteen studies met the inclusion criteria and these studies varied considerably in terms of their study characteristics (e.g., characteristics of participants, study designs, and outcome measures). The results also showed that the three basic psychological needs, intrinsic motivation, extrinsic autonomous regulation, and amotivation had small to large effects on predicting global burnout and its three dimensions. However, controlled regulation showed no or weak correlations with the burnout subscales.ConclusionsSelf-determination theory was generally supported in explaining athlete burnout.  相似文献   
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This paper examines whether emotional message content alters the effects of structural complexity and information density on available resources, measured by secondary task reaction times (STRTs), and message encoding, measured by audio recognition. In addition, hypotheses relating motivational activation and resource availability based on the motivational activation concepts of positivity offset (greater appetitive activation in a neutral environment) and negativity bias (faster aversive activation) influence are tested. Results replicate previous research supporting the contention that STRTs measure available resources. In addition, they show that the basic pattern of STRTs and recognition as a function of allocated and required resources is relatively consistent regardless of emotional content of the message. Emotion appears to function as a constant, increasing both resource allocation and resources required. Finally, these data provide some initial support for predicted relationships between motivational activation and resource allocation based on the constructs of positivity offset and negativity bias.  相似文献   
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Cardiomyopathy is a genetically and clinically heterogeneous, life threatening disease which affects people of all ages. Recent guidelines provide recommendations for cardiac screening and genetic testing in at-risk relatives, but the uptake and impact of these measures in the United States is unknown. This is a single institution retrospective study that characterizes the uptake of cardiac screening and genetic testing for relatives of a cohort of 57 probands with hypertrophic (HCM) and dilated cardiomyopathy (DCM) who underwent both clinical evaluation and genetic testing. Cardiac screening was indicated for 302 relatives. One hundred and seventy-three (57 %) completed cardiac screening. Forty of the 57 probands were mutation positive and genetic testing was indicated for 213 relatives. Eighty-four (39 %) completed genetic testing. The uptake of cardiac surveillance was greater than the uptake of genetic testing (p?<?0.0001) among relatives of mutation positive probands. Within the group of at-risk, asymptomatic relatives of probands, cardiac screening and genetic testing were positive in 25 % and 40 % of cases, respectively. These data demonstrate the important role and utility of cascade cardiac screening and genetic testing in the care of patients and families with HCM or DCM. The approach to cardiac screening and genetic testing should be family-specific and requires expertise in the genetics of cardiomyopathy.  相似文献   
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Abstract

The objective of this study was to investigate the mediating role of coping strategies in the relationships between neuroticism, social support, and depression in two groups of adolescents: earthquake group and examination group. Adolescents facing earthquake stress (earthquake group, N=219) completed measures of neuroticism, perceived social support, coping strategies, and self-rating depression. Similarly, adolescents facing examination stress (examination group, N=241) completed the same measures. Results indicated that the earthquake group reported more use of secondary control engagement coping, whereas the examination group reported more use of primary control engagement coping. In addition, neuroticism was more strongly associated with coping in earthquake group and coping strategies explained significantly larger part of the relationship between neuroticism and depression. In contrary, perceived social support was more strongly associated with coping in examination group, and coping strategies explained significantly larger part of the relationship between perceived social support and depression.  相似文献   
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ABSTRACT

This study investigated the effects of using digital augmentation to enhance an exhibit device to influence conceptual understanding about a science topic in a science museum setting. In particular, the study considered how students in Grades 6–8 engaged with the device that was available in both augmented and nonaugmented (control) conditions. Results show increased cognitive (critical thinking) skills when the digital augmentation was present that we hypothesize led to increased conceptual gains. We illustrate how this research contributes to three important areas of need identified in informal science literature: the need for evidence of conceptual and cognitive gains; the need for understanding how digital platforms improve the learning experience; and the need to demonstrate how designed interactive devices may impact higher order skills such as critical thinking and theorizing.  相似文献   
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Eye-tracking technique and visual search task were employed to examine the cognitive advantage for one’s own name and the possible effect of familiarity on this advantage. The results showed that fewer saccades and an earlier start time of first fixations on the target were associated with trials in which participants were asked to search for their own name, as compared to search for personally familiar or famous names. In addition, the results also demonstrated faster response times and higher accuracy in the former kind of trials. Taken together, these findings provide important evidence that one’s own name has the potential to capture attention and that familiarity cannot account for this advantage.  相似文献   
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This study examined prevalence and predictors of posttraumatic growth in 180 accidentally injured patients of mainland China in their convalescence stage, investigating its relationships with demographic and accidental injury variables, personality, posttraumatic stress disorder (PTSD) symptoms, and coping styles. Our results showed that posttraumatic growth (PTG) presented mostly in the domain of Relating to Others and indicated that PTG was significantly related to marital status, educational level, personality, coping styles, and PTSD symptoms. Avoidance of PTSD symptoms, Openness to experience, and positive coping were significant predictors of PTG. The findings emphasize that when promoting PTG of accidentally injured patients, healthcare providers should facilitate patients utilizing personal resources, understand PTG coexists with PTSD symptoms, and adjust interventions based on the coping styles the patients have adopted.  相似文献   
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