• Transactions of Materials Processing
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• v.19 no.7
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• pp.416-422
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• 2010

The $\{10\bar{1}2\}$ twinning characteristics, such as active twin variants, volume fraction of twins with strain, twin morphology, twin texture and angle relationship between twins, were dependent on the activation mode (i.e., tension parallel to the caxis or compression perpendicular to the c-axis). The selection criterion of active twin variants was governed by the Schmid law. This activation of selected twin variants depending on the activation mode consequently caused a totally different plastic deformation behavior in two activation modes. The differences in the deformation characteristics, such as flow stress and work hardening rate, between both activation modes were explained in relation with activation stresses for slips and twinning, relative activities of twinning and slips during plastic deformation, grain refining effect by twin boundaries (Hall-Petch effect), and twinning-induced change in activities of slips.

• Applied Microscopy
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• v.46 no.4
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• pp.238-243
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• 2016

Twinning-induced plasticity (TWIP) steels with the austenite structure containing high manganese exhibit both good strength and excellent formability. Such properties originate from crystallographic slip and mechanical twins produced when the austenite structure is under mechanical stress. There are 12 twin systems, referred to as twin variants, when slip is induced. These twin systems include twin planes and twin directions and play an important role in determining strength and ductility of the material by strongly influencing texture formation of the austenite structure. In the present study, twins produced in a high-Mn TWIP steel as a result of uniaxial tension were observed using a transmission electron microscope; a comparative analysis was performed through interaction energy calculations. Electron diffraction was used to determine the twin system with respect to the uniaxial tension direction in each grain. Both the Schmid factors and interacting energies required for the generation of twins were calculated and subsequently compared with experimental results. This approach demonstrated the possibility of predicting the deformation behavior of the material.

• Genomics & Informatics
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• v.9 no.2
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• pp.45-51
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• 2011

How personality forms and whether personality genes exist are long-studied questions. Various concepts and theories have been presented for centuries. Personality is a complex trait and is developed through the interaction of genes and the environment. Twin and family studies have found that there are critical genetic and environmental components in the inheritance of personality traits, and modern advances in genetics are making it possible to identify specific variants for personality traits. Although genes that were found in studies on personality have not provided replicable association between genetic and personality variability, more and more genetic variants associated with personality traits are being discovered. Here, we present the current state of the art on genetic research in the personality field and finally list several of the recently published research highlights. First, we briefly describe the commonly used self-reported measures that define personality traits. Then, we summarize the characteristics of the candidate genes for personality traits and investigate gene variants that have been suggested to be associated with personality traits.