Phase stability of Al3Nb as a function of nickel additions

Abstract

Phase stability of the intermetallic compound Al₃Nb is investigated as a function of nickel additions by band structure calculations based on an extended Hueckel tight-binding method. With this method, the electronic structure and total energies of the Al_6-n -Ni _n Nb₂ compounds (where n is an integer from 0 to 6) are calculated for both D0₂₂ and L1₂ structures under the assumption that nickel substitutes for aluminium. The electronic total energies obtained from integration of the energy states of all electrons considered have shown that the D0₂₂ structure is stable in the binary Al₃Nb compound as compared with the L1₂ structure; conversely, the L1₂ structure is stable for compounds with n values greater than 1. These calculations are in good agreement with X-ray diffraction results reported by Schubert and co-workers. Differences in the electronic total energy per atom between D0₂₂ and L1₂ are - 0·79 eV and 0·56 eV for n equal to 0 and 2, respectively.     

Unpacking Cultural Variations in Peak-Experiences: Cross-Cultural Comparisons of Early Childhood Recollection Between Hong Kong and Brazil

In this cross-cultural study, 115 Hong Kong Chinese and 117 Brazilian college students described a childhood peak-experience (occurring before the age of 14) and provided a self-rating on its enduring impact. Among various categories of peak-experiences, both Hong Kong Chinese and Brazilians reported interpersonal joy most frequently; the second most frequently reported category was external achievement for the Hong Kong sample and developmental landmark for the Brazilian sample. Compared with Brazilians’ narratives, those of Hong Kong Chinese were more social-focused, involving greater number of other people, but less specific. These characteristics of autobiographical memory, i.e., memory focus (self vs. social), memory specificity (specific vs. general), and the number of other people involved, significantly mediated the relation between culture and interpersonal joy. The present findings have extended research on peak-experiences to cross-cultural contexts and incorporated measures of autobiographical memory to unpack cultural variations in these two collectivist societies.     

成人期人际性问题解决的策略取向研究

采用开放式问卷,考察252名25至75岁的成人解决人际性问题的策略取向。结果表明：总体上中国成人偏重于二级控制取向;成人前期个体较其他年龄段成人表现出更多的一级控制取向;情境因素对成人的策略取向有较大影响,并且这种影响对不同年龄段成人所产生的效应存在明显差异。     

Systematic angular biases in the representation of visual space

Representing spatial information is one of our most foundational abilities. Yet in the present work we find that even the simplest possible spatial tasks reveal surprising, systematic misrepresentations of space—such as biases wherein objects are perceived and remembered as being nearer to the centers of their surrounding quadrants. We employed both a placement task (in which observers see two differently sized shapes, one of which has a dot in it, and then must place a second dot in the other shape so that their relative locations are equated) and a matching task (in which observers see two dots, each inside a separate shape, and must simply report whether their relative locations are matched). Some of the resulting biases were shape specific. For example, when dots appeared in a triangle during the placement task, the dots placed by observers were biased away from certain parts of the symmetry axes. But other systematic biases were not shape specific, and seemed instead to reflect differences in the grain of resolution for different regions of space. For example, with both a circle and even a shapeless configuration (with only a central landmark) in the matching task, observers were better at discriminating angular differences (when a dot changed positions around the circle, as opposed to inward/outward changes) in cardinal versus oblique sectors. These data reveal a powerful angular spatial bias, and highlight how the resolution of spatial representation differs for different regions and dimensions of space itself.

     

When to Use Broader Internalising and Externalising Subscales Instead of the Hypothesised Five Subscales on the Strengths and Difficulties Questionnaire (SDQ): Data from British Parents,Teachers and Children

The Strengths and Difficulties Questionnaire (SDQ) is a widely used child mental health questionnaire with five hypothesised subscales. There is theoretical and preliminary empirical support for combining the SDQ’s hypothesised emotional and peer subscales into an ‘internalizing’ subscale and the hypothesised behavioral and hyperactivity subscales into an ‘externalizing’ subscale (alongside the fifth prosocial subscale). We examine this using parent, teacher and youth SDQ data from a representative sample of 5–16 year olds in Britain (N = 18,222). Factor analyses generally supported second-order internalizing and externalizing factors, and the internalizing and externalizing subscales showed good convergent and discriminant validity across informants and with respect to clinical disorder. By contrast, discriminant validity was poorer between the emotional and peer subscales and between the behavioral, hyperactivity and prosocial subscales. This applied particularly to children with low scores on those subscales. We conclude that there are advantages to using the broader internalizing and externalizing SDQ subscales for analyses in low-risk samples, while retaining all five subscales when screening for disorder.     

Self-control and frequency of model presentation: Effects on learning a ballet passé relevé

The purpose of this experiment was to examine the combined effects of self-control and frequency of model presentation on learning a complex motor skill, i.e., ballet passé relevé. Before practice started self-control participants were asked to choose two viewings or six viewings (before practice and then every five trials) and the externally controlled groups were yoked to their self-control counterparts. All participants completed 15 acquisition trials followed by 5 trials for the immediate and 5 trials for the delayed retention tests 48 hours later. Dependent variables included cognitive representation scores, physical reproduction rankings, and balance time. Statistical analyses indicated that under limited physical practice conditions self-control and higher frequency of model presentation facilitated the development of cognitive representation and did not produce further benefits in movement reproductions and balance time. The results were discussed with respect to the social cognitive theory.     

Weight discrepancy and body appreciation among women in Poland and Britain

Previous studies have suggested that the process of transmigration has detrimental effects on the body image of migrants relative to women in the country of origin. In the present work, we examined the body image of Polish migrants in Britain (n = 153), Polish women in Poland (n = 153), and a comparison group of British White women (n = 110). Participants completed a measure of actual-ideal weight discrepancy and the Body Appreciation Scale (BAS). Contrary to hypotheses, our results showed that Polish women in Poland had significantly higher weight discrepancy than their counterparts in Britain. Further analyses showed that the BAS reduced to two dimensions among Polish participants, with Polish participants in Poland having significantly lower body appreciation than Polish migrants. We suggest that the sociocultural changes that have taken place in Eastern Europe may place women in that region at relatively high risk for developing negative body image.     

一致的先前知识对类别学习影响机制探讨

探讨一致的先前知识对类别学习的影响,包括2个实验。被试是112名大学生,分别探讨不同实验任务和不同项目呈现时间引发的机械特征在类别学习中的重要程度和加工程度不同的情况下先前知识对类别学习的影响。结果表明:(1)在实验任务为项目类别归属判断任务时,机械特征重要程度低,主题特征与机械特征在学习上存在竞争关系;在实验任务为项目类别归属及记忆任务时,机械特征重要程度高,主题特征与机械特征在学习上存在促进关系。(2)在限制步速呈现项目时,机械特征加工程度低,主题特征与机械特征在学习上存在竞争关系;而在自定步速呈现项目时,机械特征加工程度高,主题特征与机械特征在学习上不存在竞争关系。     

"嫁主里面的人"——乡村基督徒姻亲结合的宗教社会学观

乡村社会出现越来越多基督徒与基督徒的姻亲结合,我们通过基督教经典<圣经>投射的神与基督徒、基督徒家庭结构、婚姻行为、婚姻观念的统计,结合婚礼发挥的姻亲结合认同、基督徒群体团结的功能分析,探析基督徒姻亲结合表达的宗教及社会需求所在:乡村基督徒姻亲结合,是信徒构建神圣与世俗秩序的宗教需求,同时,宗教关系的血亲化、家族化,满足了作为基督徒的村民对熟人社会再造的社会需求.     

Emotional context at learning systematically biases memory for facial information

Emotion influences memory in many ways. For example, when a mood-dependent processing shift is operative, happy moods promote global processing and sad moods direct attention to local features of complex visual stimuli. We hypothesized that an emotional context associated with to-be-learned facial stimuli could preferentially promote global or local processing. At learning, faces with neutral expressions were paired with a narrative providing either a happy or a sad context. At test, faces were presented in an upright or inverted orientation, emphasizing configural or analytical processing, respectively. A recognition advantage was found for upright faces learned in happy contexts relative to those in sad contexts, whereas recognition was better for inverted faces learned in sad contexts than for those in happy contexts. We thus infer that a positive emotional context prompted more effective storage of holistic, configural, or global facial information, whereas a negative emotional context prompted relatively more effective storage of local or feature-based facial information