A dislocation based theory for the deformation hardening behavior of DP steels : Impact of martensite content and ferrite grain size

A dislocation model, accurately describing the uniaxial plastic stress-strain behavior of dual phase (DP) steels, is proposed and the impact of martensite content and ferrite grain size in four commercially produced DP steels is analyzed. It is assumed that the plastic deformation process is localized to the ferrite. This is taken into account by introducing a non-homogeneity parameter, f(e), that specifies the volume fraction of ferrite taking active part in the plastic deformation process. It is found that the larger the martensite content the smaller the initial volume fraction of active ferrite which yields a higher initial deformation hardening rate. This explains the high energy absorbing capacity of DP steels with high volume fractions of martensite. Further, the effect of ferrite grain size strengthening in DP steels is important. The flow stress grain size sensitivity for DP steels is observed to be 7 times larger than that for single phase ferrite.

Evaluation of communication behavior in persons with dementia during caregivers’ singing

The number of persons with dementia (PWD) is increasing rapidly worldwide. Cognitive impairments and communication difficulties are common among PWD. Therefore, gaining mutual togetherness in caring relation between PWD and their caregivers is important. This study was to investigate the effects of music therapeutic care (MTC) during morning care situations on improving verbal and nonverbal communication behaviors in people with dementia. An observation study with 10 PWD participating. Videotaped interactions (VIO) between PWD and their caregivers were conducted during eight weekly sessions, four recordings consisted of usual morning care and four recordings were of morning care with MTC intervention. The Verbal and Nonverbal Interaction Scale was used to analyze the recorded interactions at a later time. The unsociable verbal variable Cursing decreased significantly (P=.037) during MTC when compared with the baseline measurement. A significant (P=.000) reduction was observed for the unsociable nonverbal variable Does not respond to question. MTC significantly (P=.01) increased the mean score for the sociable nonverbal variable – Calm – relaxed. For sociable verbal communication, significant differences were observed for the variables Use coherent communication (P=.012), Use relevant communication (P=.009), Responds to questions (P=.000), Humming (P=.004), Singing (P=.000). MTC during morning care situations can be an effective non-pharmacological treatment, as well as nursing intervention in order to improve sociable communication behaviors, as well as reduce unsociable communication behaviors of PWDs