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111.
Nanoscale Cu-rich precipitates (CRPs) are one of the most important microstructural nano-features responsible for embrittlement and hardening of reactor pressure vessels (RPVs), which threaten the safe operation of nuclear power plants (NPPs) and hinder the lifetime extension of nuclear reactors. A thermally aged Fe-1.1 wt.%Cu alloy, which is used to simulate embrittlement of the irradiated RPV steels, was treated by electropulsing with various parameters. The effect of electropulsing on nanoscale CRPs was investigated by using transmission electron microscopy (TEM). Compared to the traditional heat treatment, the electropulsing treatment (EPT) can accelerate the dissolution of CRPs in an aged Fe-Cu alloy on account of the higher atomic drift flux and the additional Gibbs free energy induced by electropulsing. More importantly, EPT is likely to be a new way of eliminating irradiation-induced Cu-rich precipitates.  相似文献   
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Bruno Latour is not the only scholar to reflect on his earlier contributions to science studies with some regret and resolve over climate skepticism and science denialism. Given the ascendency of merchants of doubt, should those who share Latour’s concerns join the scientists they study in circling the wagons, or is there a productive role still for science studies to question and critique scientists and scientific institutions? I argue for the latter, looking to postpositivist feminist philosophy as exemplified by Alison Wylie and Lynn Nelson, among others, as a guide. Feminist philosophers of science who ground their analysis in a detailed understanding of scientific practice are not science’s champions nor its antagonists, but they do stand in a distinct relationship to science. If not merchants of doubt, are they scientific gadflies or perhaps in scientific loyal opposition? Though these notions can underwrite useful approaches to science studies, neither captures the distinctive interdependency and interestedness of feminist philosophers and science. I suggest that we would be better served by the notion of trustworthy science criticism, building on the analyses of trust and trustworthiness by Annette Baier, among others, attendant to the dynamics of interdependency in trust relationships.  相似文献   
113.
According to Bernard Williams' “anti‐tyranny argument,” it is important for citizens to have access to true information about the exercise of political power in order to check the tendency of governments and politicians to become tyrannous. Although Williams thinks the argument is one of the better arguments for the importance of truthfulness in politics, he acknowledges 2 limitations. First, it appears to offer little more than the truism that tyranny is a bad thing—a truism that will be accepted by all but tyrants themselves. Second, it may not offer any reasons for the importance of true information about forms of political power, which do not seem tyrannous. I argue that kind of political analysis required to apply the anti‐tyranny argument enables it to overcome both limitations. In so doing, I show that it has a clear advantage over rival arguments for the importance of truthfulness in politics.  相似文献   
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Previous studies with emotional face stimuli have revealed that our ability to identify different emotional states is dependent on the faces’ spatial frequency content. However, these studies typically only tested a limited number of emotional states. In the present study, we measured the consistency with which 24 different emotional states are classified when the faces are unfiltered, high-, or low-pass filtered, using a novel rating method that simultaneously measures perceived arousal (high to low) and valence (pleasant to unpleasant). The data reveal that consistent ratings are made for every emotional state independent of spatial frequency content. We conclude that emotional faces possess both high- and low-frequency information that can be relied on to facilitate classification.  相似文献   
117.
Mediation analyses have provided a critical platform to assess the validity of theories of action across a wide range of disciplines. Despite widespread interest and development in these analyses, literature guiding the design of mediation studies has been largely unavailable. Like studies focused on the detection of a total or main effect, an important design consideration is the statistical power to detect indirect effects if they exist. Understanding the sensitivity to detect indirect effects is exceptionally important because it directly influences the scale of data collection and ultimately governs the types of evidence group-randomized studies can bring to bear on theories of action. However, unlike studies concerned with the detection of total effects, literature has not established power formulas for detecting multilevel indirect effects in group-randomized designs. In this study, we develop closed-form expressions to estimate the variance of and the power to detect indirect effects in group-randomized studies with a group-level mediator using two-level linear models (i.e., 2-2-1 mediation). The results suggest that when carefully planned, group-randomized designs may frequently be well positioned to detect mediation effects with typical sample sizes. The resulting power formulas are implemented in the R package PowerUpR and the PowerUp!-Mediator software (causalevaluation.org).  相似文献   
118.
中学生生活满意度的跨文化比较研究   总被引:3,自引:0,他引:3  
目的:比较不同国家(地区)中学生生活满意度的差异。方法:运用《多维学生生活满意度量表》对爱尔兰、美国、高加索、以色列、中国五个国家(地区)共计1345名中学生的生活满意度进行了测量。结果:(1)五国(地区)中学生高一般生活满意度组人数分布百分比由多到少依次为爱尔兰、美国、高加索、以色列、中国;(2)五国(地区)女生的家庭满意度高于男生,男生的学校满意度高于女生;(3)爱尔兰学生的家庭满意度最高,中国学生的朋友和学校满意度最高,以色列学生的生活环境满意度最低、自我满意度最高;(4)性别和国家(地区)对中学生的学校、生活环境、自我的满意度存在交互作用。结论:不同国家(地区)中学生的生活满意度存在差异,社会文化背景是影响中学生生活满意度的重要因素。  相似文献   
119.
Subtyping obsessive-compulsive disorder: A taxometric analysis   总被引:2,自引:0,他引:2  
Obsessive-compulsive disorder (OCD) is a heterogeneous condition comprising multiple symptoms. Researchers have identified OCD subtypes using a range of symptom-based research methods, including factor and cluster analyses and examination of differential treatment response. These methods can be challenged on the grounds that they fail to demonstrate the existence of discrete taxonomic entities. Furthermore, no study has examined subtyping on the basis of cognitive characteristics. In the present study, the categorical vs. dimensional status of 6 possible subtypes of OCD was examined using taxometric methods. Three potential cognitive subtypes (based on high levels of responsibility/threat estimation, perfectionism/certainty, and importance/control of thoughts) and 3 potential symptomatic subtypes (based on elevated levels of contamination obsessions and cleaning compulsions, checking, and obsessionality) were examined using the MAXEIG and MAMBAC procedures in a sample of 404 diagnosed cases of OCD. Findings favored dimensional models of the potential responsibility, perfectionism, checking, and contamination subtypes, but offered qualified support for taxonic models of the importance/control of thoughts and obsessional subtypes. Implications for the subclassification of OCD are discussed.  相似文献   
120.
Compulsive checking is known to influence memory, yet there is little consideration of checking as a cognitive style within the typical population. We employed a working memory task where letters had to be remembered in their locations. The key experimental manipulation was to induce repeated checking after encoding by asking about a stimulus that had not been presented. We recorded the effect that such misleading probes had on a subsequent memory test. Participants drawn from the typical population but who scored highly on a checking‐scale had poorer memory and less confidence than low scoring individuals. While thoroughness is regarded as a quality, our results indicate that a cognitive style that favours repeated checking does not always lead to the best performance as it can undermine the authenticity of memory traces. This may affect various aspects of everyday life including the work environment and we discuss its implications and possible counter‐measures. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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