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In order to investigate the effect of strain rate on TRIP effect in metastable austenitic steels, tensile deformation behavior of a JIS-SUS301L steel was examined at wide range of strain rates between 10 3 /s and 10 Ϫ3 /s, in addition of the comparison with data of stable austenitic steel (JIS-SUS310S). Concerning of the SUS301L steel, the 0.2% proof stress increased and the uniform elongation decreased with increasing of strain rate. The tensile strength decreased with an increase in strain rate between 10 Ϫ3 /s and 10 1 /s and then increased again at strain rate more than 10 1 /s. The significant difference between the strain rate dependences on tensile strength and uniform elongation of SUS301L and SUS310S was clarified especially at strain rates between 10 Ϫ3 /s and 10 0 /s. As far as the effect of strain rate on stress-induced martensitic transformation behaviors is concerned, the volume fraction of stress-induced martensite at the same true strain decreased with increasing of strain rate. These stress-induced transformation behaviors were associated with the tensile strength and uniform elongation of SUS301L steel between 10 Ϫ3 /s and 10 0 /s. The conditions of stress-induced martensitic transformation in order to obtain better uniform elongation at a high strain rate of 10 0 /s were discussed by the calculations using the Weng secant method.

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Previous research indicates that imitation of gestures in preschool children is goal-directed. A goal may be a salient feature from a presented movement; that goal may be imitated correctly, but other features were ignored, resulting in observable errors. Objects (e.g., a dot on the table) can become the most salient features and presence or absence of objects influences imitation responses. Imitation responses were examined under conditions in which objects could not be used directly as the most salient feature. 60 children (M age = 5:6) were assigned to Gestural, Dot, No-dot, and Un-dot conditions, and they were asked to imitate 20 movements. The type of presented movement and the occurrence of correct, mirror, and error responses were examined. Responses in the Un-dot condition were similar to those in the Dot condition. Error responses in the Un-dot condition were related to age. Children may extract a more abstract feature in a context without visible objects. This ability is associated with a cognitive mechanism developed in preschool years.