Influence of plastic strain localisation on the mechanical properties of metal matrix composites

The aim of the present study is to reveal the most critical underlying factor influencing the mechanical properties of metal matrix composites (MMCs). It is shown that the mechanical properties of MMCs are essentially governed by the degree of strain localisation during plastic deformation. In other words, the MMCs exhibit superior mechanical performance only if the strain localisation is obviously inhibited and the accumulated stresses can be effectively transferred out. The work provides a new perspective in guiding the design of next-generation high-performance MMCs by suppressing the strain localisation as far as possible.     

Dendrite growth velocity in the undercooled melt of glass forming Ni50Zr50 compound

Glass-forming Ni₅₀Zr₅₀ intermetallic compound is containerless undercooled and solidified using electrostatic levitation. Large undercoolings up to ?T = 300 K are achieved. The dendrite growth velocity of the congruently melting alloy is measured as a function of undercooling using a high-speed camera technique. The experimental data is analysed within a sharp interface theory. It is found that the driving force of crystallisation is controlling the growth kinetics at ?T < 250 K but at larger undercoolings the growth kinetics is progressively controlled by atomic diffusion. This leads to a slowing down of the growth velocity. The maximum velocity and the temperature at which the maximum occurs (T_max) are inferred from the dendrite growth velocity – undercooling relation. The relation of the temperature T_max and the glass temperature fits into a general classification scheme for glass-forming systems. The kinetic and thermal undercooling terms are calculated within dendrite growth theory as a function of the total undercooling. At ?T > 126 K, the kinetic undercooling dominates and increases rapidly with the undercooling ?T. The maximum prefactor of the kinetic undercooling is plotted vs. the reciprocal temperature. Its temperature dependence is discussed.     

Dealing with Big Numbers: Representation and Understanding of Magnitudes Outside of Human Experience

Being able to estimate quantity is important in everyday life and for success in the STEM disciplines. However, people have difficulty reasoning about magnitudes outside of human perception (e.g., nanoseconds, geologic time). This study examines patterns of estimation errors across temporal and spatial magnitudes at large scales. We evaluated the effectiveness of hierarchical alignment in improving estimations, and transfer across dimensions. The activity was successful in increasing accuracy for temporal and spatial magnitudes, and learning transferred to the estimation of numeric magnitudes associated with events and objects. However, there were also a number of informative differences in performance on temporal, spatial, and numeric magnitude measures, suggesting that participants possess different categorical information for these scales. Educational implications are discussed.     

Old Wine in New Bottles? The Case of Self‐compassion and Neuroticism

Research on self‐compassion, which is defined as being understanding and kind to oneself when confronted with negative experiences, has produced an impressive number of articles in recent years. This research shows that individual differences in self‐compassion, as measured by the Self‐Compassion Scale (SCS), are positively related to life satisfaction, health and social functioning. However, a critical and systematic test of self‐compassion from a personality perspective has not yet conducted so far. In the present study (N = 576), we (i) tested the factor structure of the SCS, (ii) examined the distinctiveness of self‐compassion with regard to the five‐factor model of personality, focusing on neuroticism, and (iii) tested the incremental predictive power of self‐compassion beyond the five‐factor model in the context of life satisfaction. Confirmatory factor analyses supported a two‐factor plus six facets solution of self‐compassion (a positive factor and a negative factor). Additional analyses revealed that the negative factor was redundant with facets of neuroticism (rs ≥ .85), whereas the positive factor had some unique variance left. However, neither the negative factor nor the positive factor could explain substantial incremental variance in life satisfaction beyond neuroticism. Recommendations for how to use the SCS are provided, and the future of research on self‐compassion is discussed. Copyright © 2017 European Association of Personality Psychology     

Usage of semantic representations in recognition memory

Meanings of words facilitate false acceptance as well as correct rejection of lures in recognition memory tests, depending on the experimental context. This suggests that semantic representations are both directly and indirectly (i.e., mediated by perceptual representations) used in remembering. Studies using memory conjunction errors (MCEs) paradigms, in which the lures consist of component parts of studied words, have reported semantic facilitation of rejection of the lures. However, attending to components of the lures could potentially cause this. Therefore, we investigated whether semantic overlap of lures facilitates MCEs using Japanese Kanji words in which a whole-word image is more concerned in reading. Experiments demonstrated semantic facilitation of MCEs in a delayed recognition test (Experiment 1), and in immediate recognition tests in which participants were prevented from using phonological or orthographic representations (Experiment 2), and the salient effect on individuals with high semantic memory capacities (Experiment 3). Additionally, analysis of the receiver operating characteristic suggested that this effect is attributed to familiarity-based memory judgement and phantom recollection. These findings indicate that semantic representations can be directly used in remembering, even when perceptual representations of studied words are available.     

父母对幼儿消极情绪的反应方式与幼儿情绪调节能力的关系

以西安市280名幼儿及其家长为被试,采用问卷法考察母亲、父亲对幼儿消极情绪的反应方式对幼儿情绪调节能力的单独效应和联合效应。结果发现：（1）母亲对幼儿消极情绪的支持反应正向预测幼儿的情绪调节能力,非支持反应负向预测幼儿的情绪调节能力;（2）父亲对幼儿消极情绪的支持反应和非支持反应显著预测女孩的情绪不稳;（3）在女孩的情绪调节能力上,母亲和父亲非支持反应的交互作用显著,部分支持了分歧模型。     

初中生应对方式、压力对社会适应的影响:纵向中介模型

青春期的适应问题及其影响因素历来是研究者关注的焦点。本研究对369名初中生从初一到初三的应对方式、压力、社会适应进行了四次调查,通过纵向中介模型考察应对方式、压力对社会适应的影响。结果表明：初一时期的积极应对方式能够直接提高初三时期的积极适应水平,直接降低消极适应水平;初一时期的消极应对方式会通过提高后期的压力间接提高初三时期的消极适应水平。     

The influence of performance on action-effect integration in sense of agency

Sense of agency refers to the subjective feeling of being able to control an outcome through one’s own actions or will. Prior studies have shown that both sensory processing (e.g., comparisons between sensory feedbacks and predictions basing on one’s motor intentions) and high-level cognitive/constructive processes (e.g., inferences based on one’s performance or the consequences of one’s actions) contribute to judgments of sense of agency. However, it remains unclear how these two types of processes interact, which is important for clarifying the mechanisms underlying sense of agency. Thus, we examined whether performance-based inferences influence action-effect integration in sense of agency using a delay detection paradigm in two experiments. In both experiments, participants pressed left and right arrow keys to control the direction in which a moving dot was travelling. The dot’s response delay was manipulated randomly on 7 levels (0–480 ms) between the trials; for each trial, participants were asked to judge whether the dot response was delayed and to rate their level of agency over the dot. In Experiment 1, participants tried to direct the dot to reach a destination on the screen as quickly as possible. Furthermore, the computer assisted participants by ignoring erroneous commands for half of the trials (assisted condition), while in the other half, all of the participants’ commands were executed (self-control condition). In Experiment 2, participants directed the dot as they pleased (without a specific goal), but, in half of the trials, the computer randomly ignored 32% of their commands (disturbed condition) rather than assisted them. The results from the two experiments showed that performance enhanced action-effect integration. Specifically, when task performance was improved through the computer’s assistance in Experiment 1, delay detection was reduced in the 480-ms delay condition, despite the fact that 32% of participants’ commands were ignored. Conversely, when no feedback on task performance was given (as in Experiment 2), the participants reported greater delay when some of their commands were randomly ignored. Furthermore, the results of a logistic regression analysis showed that the threshold of delay detection was greater in the assisted condition than in the self-control condition in Experiment 1, which suggests a wider time window for action-effect integration. A multivariate analysis also revealed that assistance was related to reduced delay detection via task performance, while reduced delay detection was directly correlated with a better sense of agency. These results indicate an association between the implicit and explicit aspects of sense of agency.     

Thank goodness it’s Friday: weekly pattern of workplace incivility

Background and objectives: Recent research has shown day-level differences in an individual’s experience of uncivil behavior; however, it is unknown if that experience follows a consistent weekly change pattern. This study extends incivility theory and research by applying latent growth curve (LGC) modeling to diary study data to understand day-to-day changes in incivility.

Design: The authors took a theory-driven approach, reviewing both mood and recovery theory that would support a decrease in incivility over the working week.

Methods: Diary survey methodology was used, with a morning and evening survey completed on five consecutive workdays by 171 (73% of the 235 who initially volunteered, 95% of those who completed any surveys) employees in the legal industry. LGC analysis was used to identify patterns of experienced incivility, mood (both measured after work), and recovery (assessed the following morning).

Results: Regardless of job demands and gender, a weekly pattern was identified with the likelihood of experiencing incivility (coded as 0?=?none, 1?=?some) decreasing from Monday to Friday by .78 each day (p?<?.001) in a relatively linear fashion with a slope factor of .34 (SE?=?0.23; p?>?.05), indicating invariance between individuals. This weekly pattern was not explained by changes in mood or recovery.

Conclusions: Results emphasize the impact of contextual factors such as time on workplace incivility and the need to consider weekly rhythms of other behaviors that are likely to affect employee well-being and productivity. Although limited to one week of data per person, the findings are likely to be relevant to studies of other forms of interpersonal mistreatment, such as social undermining and interpersonal conflict.