Nanoindentation creep behavior of grain boundary in pure magnesium

Nanoindentation creep tests were performed at the grain boundary and grain interior in pure magnesium. The grain boundary showed a high strain rate sensitivity exponent and was dominated by grain boundary sliding due to the high diffusion rate at the grain boundary. The grain boundary affected the deformation behavior of the area at a distance of 2 µm into the grain interior. On the other hand, the grain interior had a low strain rate sensitivity exponent, because its matrix was too large to be influenced by the grain boundary. The deformation mechanism in the grain interior was determined to be dislocation slip.     

Intergenerational Transmission of Parenting Style and Personality: Direct Influence or Mediation?

In order to examine the relationships between parenting styles and personality traits over generations, a cross-sectional questionnaire study was conducted for fathers and mothers of school-age children of grades 5–9. The parenting styles measured by the Parental Bonding Instrument (PBI) and the personality traits measured by the Temperament and Character Inventory (TCI) were correlated within and between the consecutive generations (the grandparents and the parents for the PBI and the parents and the children for the TCI). A series of structural equation modeling showed that (1) while the parenting styles were transmitted directly from the grandparents to the parents, it was partly mediated by the fathers’ Co-operativeness (C) but not so for the mothers, (2) while the personality traits were transmitted directly from the parents to the children, it was only the fathers’ parenting styles that mediated C, and (3) the parents’ parenting styles had independent effects upon the children’s personality traits.     

Fracture mechanism of a coarse-grained magnesium alloy during fracture toughness testing

The fracture mechanism during fracture toughness testing has been investigated on a coarse-grained magnesium alloy, with an average grain size of ～50 µm, and a low fracture toughness. The results show that {1012}-type deformation twins are formed at the crack tip and many dislocations pile up on these boundaries. The accumulated strains at these boundaries become the origin of fracture; i.e. cracks propagate along these boundaries between the deformation twins and the matrix.     

The effects on the predictive variance of a new subject’s score for a new test

Abstract: It is often required to predict the scores or their variations under interest. Ishii and Watanabe (2001) investigated, in the context of psychological measurement, the Bayesian predictive distribution of a new subject’s scores for tests and subjects’ scores for a new test. In this paper, the Bayesian posterior predictive distribution of a new subject’s scores for a new parallel test were considered. And the effects of the number of subjects, the number of the tests, and the test reliability were investigated. Then, it was found that, under assumptions that (co)variance parameters are known, the predictive variance of a new subject’s score for a new test was equal to the predictive variances of the new subject’s scores for the existent tests. It was also found that the effect of the number of subjects was relatively large and the effect of the number of tests was relatively small, when a new subject’s scores for existent tests were not observed.     

Influence of the role of a partner on anxiety due to a physically threatening situation

This study aimed to examine the influence of the presence of a partner in terms of affiliation level and role on anxiety in a physically threatening situation.

In the first experiment, nine male subjects waited alone for the electric shock, and the other nine subjects waited with their partner.

In the second experiment, 36 female subjects were assigned to four experimental groups by the difference of the role of a partner (coactor or audience) and the affiliation level of a partner (friend or stranger), and subjects waited for the electric shock with their partner.

It was found that anxiety of subjects decreased when the partner was a coactor and/or a friend. It was suggested that these two functioned differently in anxiety reduction in a physically threatening situation.     

The Role of Coping Styles and Self-efficacy in the Development of Dysphoric Mood Among Nursing Students

Coping styles and self-efficacy have been recognized as important determinants of dysphoric mood. The objectives of this study were to determine the influence of these two factors on depression and anxiety in Japanese students. A set of questionnaires, including the Hospital Anxiety and Depression (HAD) Scale, the Coping Inventory for Stressful Situations (CISS), and the Self-efficacy Scale (SES) was distributed to 146 nursing students. Structural equation modelling was conducted to specify the relationships between measured variables. The HAD depression and anxiety scores were predicted by emotion-oriented coping. The HAD depression alone was predicted by avoidance-oriented coping. Self-efficacy scores predicted the emotion-oriented coping and HAD depression scores. Students’ dysphoric moods were influenced by emotional-oriented coping that mediated the effects of low self-efficacy, and self-efficacy also had a direct effect on depression.     

Observation system for the control of the hive environment by the honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis>)

The honeybee can control its hive environment to survive drastic changes in the field environment. To study the control of multiple environmental factors by honeybees, in this experiment, we developed a continual and simultaneous monitoring system for the temperature, moisture, and carbon dioxide (CO₂) concentration in a honeybee hive. Changes in hive weight, CO₂ production rate, and honeybee behavior were also monitored to estimate energy costs and behavioral activity for the environmental regulation. Measurements were conducted in August 2008. We found that the honeybee hive has a microclimate different from the ambient climate, and that the difference was partly accompanied by changes in honeybee activity. Our results also suggest that hive temperature, humidity, and CO₂ concentrations are controlled by different mechanisms. Additional monitoring of the hive environment and honeybee behavior for longer periods would enable us to understand the mechanisms of environmental control by honeybees, which is one of the behaviors that define honeybees as social insects.     

Deformation structure after fracture-toughness test of Mg–Al–Zn alloys processed by equal-channel-angular extrusion

Fracture toughness and deformation structures have been investigated using an AZ31 magnesium alloy processed by equal-channel-angular extrusion (ECAE). The ECAE-processed alloy (as-ECAE) was annealed at 573?K for 24?h (annealed-ECAE). The average grain sizes of as-ECAE and annealed-ECAE alloys were 4.0 and 16.3?µm, respectively. The plane-strain fracture toughness K _IC, obtained by stretched-zone analysis in as-ECAE and annealed-ECAE, were estimated to be 27.3 and 23.5?MPa/m^1/2, respectively. From optical microstructural observations in samples after the fracture-toughness tests, deformation twins were observed in annealed-ECAE. No deformation twins were observed in as-ECAE. In addition, dislocations on basal planes, as well as on non-basal planes, were activated in as-ECAE. It is concluded that the enhancement of the fracture toughness in the fine-grain structure was related to a reduction of deformation twins and dislocation movement in non-basal planes.     

Ductile fracture mechanism in fine-grained magnesium alloy

The ductile fracture mechanism in a fine-grained magnesium alloy has been investigated by transmission electron microscopy-focused ion beam techniques. In coarse-grained or conventional magnesium alloys, twins form at the very beginning of the deformation process, and crack propagation occurs through the twin boundaries. However, in the alloy used in this study, subgrain structures were found instead of twins at the crack tip. Nanoscale twins formed subsequently owing to large stress in the crack propagation route. The fine-grained alloys showed high fracture toughness resulting from resistance to the twins at the beginning of the deformation.     

Angle illusion in a straight road

We report a new angle illusion observed when viewing a real scene involving a straight road. The scene portrays two white lines which outline a traffic lane on a road and converge to a vanishing point. In experiment 1, observers estimated the angle created by these converging lines in this scene or in its image projected onto a screen. Results showed strong underestimation of the angle, ie over 50% for observations of both the real scene and its projected image. Experiment 2 assessed how depth cues in projected images influence the angle illusion. Results showed that this angle illusion disappeared when scene information surrounding convergent lines was removed. In addition, the illusion was attenuated with projection of an inverted scene image. These findings are interpreted in terms of a misadoption of depth information in the processing of angle perception in a flat image; in turn, this induces a massive angle illusion.