Twinning behaviour of TWIP steel studied by Taylor factor analysis

The twinning behaviour of Twinning-induced plasticity (TWIP) steel has been studied by analysing the grain orientation and the Taylor factor, based on microstructural and electron backscatter diffraction device observations. It is demonstrated that the Taylor factor can give an important guideline for determining the deformation mode of TWIP steel. The higher the Taylor factor, the easier the formation of twins and thus a tendency for the deformation mode to be mechanical twinning, while a low Taylor factor corresponds to a slip deformation mode. When the loading temperature is relatively low, the high Taylor factor regions increase and thus deformation twinning becomes easier while slip becomes more difficult, leading to increased tensile stress and decreased elongation.     

On the plasticity event in metallic glass

Based on a systematic molecular dynamics analysis, this study reveals that plastic deformation of metallic glass is not through a uniform configuration change but via many localized plasticity events. These events are manifested by the atomic clusters of high kinetic energy and high strain rate, emerging even in the elastic deformation regime. The life of such a plasticity event is on the order of 10^?12?s, during which the distribution of kinetic energy follows a power law. The study shows that yielding in metallic glass occurs at the sudden surge point of the number of plasticity events. In the steady plastic deformation regime, the continuous nucleation and annihilation of the plastic events lead to a steady flow stress and stabilized total potential energy.     

Beyond Heritability: Twin Studies in Behavioral Research

ABSTRACT— The heritability of human behavioral traits is now well established, due in large measure to classical twin studies. We see little need for further studies of the heritability of individual traits in behavioral science, but the twin study is far from having outlived its usefulness. The existence of pervasive familial influences on behavior means that selection bias is always a concern in any study of the causal effects of environmental circumstances. Twin samples continue to provide new opportunities to identify causal effects with appropriate genetic and shared environmental controls. We discuss environmental studies of discordant twin pairs and twin studies of genetic and environmental transactions in this context.     

The relationship between dynamic strain aging and serrated flow behaviour in magnesium alloy

The relationship between dynamic strain ageing (DSA) and serrated flow has been investigated via alternately switching strain rates at various temperatures in a Mg–3Nd–1Zn alloy. The results reveal that serrated flow is enhanced with decreasing strain rate and increasing temperature and tends to vanish, while the DSA continually intensifies as revealed by a higher flow stress even after the serration flow disappears. A mechanism is proposed, which could explain some abnormal deformation behaviour, such as a negative strain rate sensitivity and thermal hardening.     

Sharing genes fosters identity fusion and altruism

Researchers have shown that the more genes twins share, the more they care about one another. Here, we examine a psychological mediator of such genetic influences, “identity fusion” (a visceral sense of oneness with them). Results supported this hypothesis. Relative to dizygotic twins, monozygotic twins reported stronger fusion and elevated desire to have contact and share experiences with their twin (Study 1), to forgive and grant favors to their twin after being disappointed by him/her (Study 2), and willingness to make sacrifices for their twin (Study 3). Fusion with the twin mediated the impact of zygosity on these outcomes. These findings demonstrate that genetic relatedness fosters a powerful feeling of union with one’s twin that predicts sharing, tolerance, and self-sacrificial behavior toward him or her.     

Size effects and Hall–Petch relation in polycrystalline cobalt

The mechanical behaviour of polycrystalline hexagonal close-packed cobalt was investigated over a large range of grain size d in order to examine the occurrence of size effects. Crystallographic texture and amount of face centred cubic allotropic phase were maintained unchanged thanks to appropriate heat treatment procedures. The Hall–Petch (HP) relation exhibits two distinct behaviours from the very beginning of plastic strain levels. The conventional HP law is fulfilled for a number of grains across the thickness t higher than a critical value (t/d)_c = 14. For t/d lower than (t/d)_c, a multicrystalline regime is evidenced highlighting a strong reduction in flow stress. The high value of (t/d)_c is related to the low-stacking fault energy of cobalt in the basal plane. The size effect is predominant in the first work hardening stage where slip mechanisms and stacking faults predominate. In the second stage, driven by mechanical twinning processes, this effect is less sensitive. Finally, the size effect could also affect the end of the elastic stage, in link with nonlinear elasticity mechanisms.     

Bion and C.G. Jung. How did the container‐contained model find its thinker? The fate of a cryptomnesia

This paper investigates the possible impact of C.G. Jung's Tavistock Lectures on Bion's concept of the living container. In the first part of the paper, the author offers clues pointing to such an essential impact, which can be found in text passages as well as in the facts of the Bion‐Beckett case, up to and including Bion's first publication of ‘The imaginary twin'. The author suggests that cryptomnesia is the result of repression targeting a highly cathected author's communication which functions like a deep interpretation for the recipient, whose new theory then is a return of the repressed content as well as a transformation of it. The second part of the paper investigates the fate of the assumed cryptomnesia. From this point of view Bion's concept of the container in itself appears to be the result of growth in the container‐contained mode. Finally the author deals with the question whether cryptomnesia in psychoanalytical literature can frequently be seen as the result of psychic growth.     

Presence of ε-martensite as an intermediate phase during the strain-induced transformation of SUS304 stainless steel

We have investigated the formation process of α′-martensite from the γ-phase induced by external strain using in situ synchrotron diffraction experiments, combined with Lorentz transmission electron microscopy (TEM) and high-resolution TEM observations. It is clearly demonstrated that ε-martensite with hexagonal symmetry appears as an intermediate structure during the plastic deformation of SUS304 stainless steel. In addition to stacking faults and dislocations, interfaces between the twin structures presumably play a key role in the formation of ε-martensite.     

Twin study of laboratory-induced aggression

The aim of this study was to explore genetic and environmental contributions to laboratory-induced aggressive behavior. On a sample of 478 adult twins (316 monozygotic), the Competitive Reaction Time Task was used for aggression induction. The results showed that the initial, basic level of aggression could be explained by both shared (45%) and nonshared environmental factors (55%), while only nonshared environmental factors (100%) had a significant influence on changes in aggression as provocation increased. Genetic factors had no influence on laboratory-induced aggression. The results highlight the importance of environmental factors in shaping situation-specific aggressive responses to provocation.     

The intersection of individual differences,personality variation, & military service: A twin comparison design

ABSTRACT

In societies where military service is voluntary multiple factors are likely to affect the decision to enlist. Past research has produced evidence that a handful of personality and social factors seem to predict service in the military. However, recent quantitative genetic research has illustrated that enlistment in the military appears to be partially heritable and thus past research is potentially subject to genetic confounding. To assess the extent to which genetic confounding exists, the current study examined a wide range of individual-level factors using a subsample of twins (n = 1,232) from the restricted-use version of the National Longitudinal Study of Adolescent to Adult Health. The results of a series of longitudinal twin comparison models, which control for the latent sources of influence that cluster within families (i.e., shared genetic and family factors), illustrated generally null findings. However, individuals with higher scores on measures of extraversion and the general factor of personality were more likely to enlist in the military, after correction for familial confounding. Nonetheless, the overall results suggest that familial confounding should be a methodological concern in this area of research, and future work is encouraged to employ genetically informed methodologies in assessments of predictors of military enlistment.