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In this study, deformation behaviors at the grain level of coarse-grained ultralow carbon steel subjected to uniaxial tension and simple shear were simulated by using a crystal plasticity finite-element method. Heterogeneity of strain distributions appeared at the early stage and remained almost unchanged in the following deformation. Localized strain bands occurred at the grain level, but the directions of the bands depended on the deformation mode. These trends agreed well with experimental results reported in a previous paper [Hama et al., ISIJ Int., 61 (2021), 1971]. The mechanisms that the direction of the localized strain bands depended on the deformation mode were studied on the basis of the slip activities. The activities of slip systems roughly followed the Schmid factor, and the slip directions of the most active slip systems were consistent with the directions of localized strain bands, suggesting that the direction of localized strain bands were determined primarily by the Schmid factor.

In this work, non-uniform deformation behavior of coarse-grained ultralow carbon steel was investigated under uniaxial tension and cyclic simple shear. A digital image correlation method was used to measure strain fields at the grain level. Heterogeneous strain distribution appeared at the early stage of the process, and the heterogeneity remained almost unchanged in the subsequent deformation. Localized strain bands were observed under both uniaxial tension and simple shear, but the directions of the bands were different between the two deformation modes. It was hypothesized that the directions of the strain bands were correlated with the planes where the maximum or minimum shear stresses occurred. During cyclic simple shear, the heterogeneity of strain distribution and occurrence of strain bands depended on the shear direction. In contrast, the number of cycles had little effect on the heterogeneity of strain distribution. Comparing the grain boundaries and the strain distributions, it was observed that many of the strain-band boundaries occurred along the grain boundaries, but some of them appeared within grains.

Premature infants are at risk for developing symptomatic postnatal cytomegalovirus (CMV) disease, including sepsis-like syndrome. We performed a retrospective case–control study including infants born before 32 weeks of gestation and diagnosed with symptomatic postnatal CMV infection during the neonatal period. Neurodevelopmental outcome was evaluated using the Kyoto Scale of Psychological Development 2001 at 18 months of corrected age and at 3 years of age. Twenty-four infants were diagnosed with postnatal CMV infection; of them, 14 had sepsis-like symptoms and 10 had laboratory test abnormalities only. Home oxygen therapy was used significantly higher in the CMV-positive group compared with the control group at hospital discharge (52% vs 21%, P=0.032). The incidence of neurodevelopmental impairment was not significantly different between the two groups at 18 months of corrected age (29% vs 17%, P=0.48) and at 3 years of age (43% vs 29%, P=0.34). Postnatal CMV infection did not have a significant influence on neurodevelopmental outcomes of symptomatic preterm infants, although those in the CMV-positive group appeared worse. Larger studies with long-term follow-up are needed for a better understanding of continued neurodevelopmental outcomes in preterm infants with postnatal CMV infection., This is an Open Access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. To view the details of this license, please visit (http://creativecommons.org/licenses/by-nc-nd/4.0/).