Atomic scale investigation of solutes and precipitates in high strength steels

Two steels, ferritic, high strength with interphase precipitation and nano-bainitic, were used to show the advances in and application of atom probe. The coexistence of the nano-scale, interphase Nb-Mo-C clusters and stoichiometric MC nano particles was found in the high strength steel after thermomechanical processing. Moreover, the segregation of carbon at different heterogeneous sites such as grain boundary that reduces the solute element available for fine precipitation was observed. The APT study of the solutes redistribution between the retained austenite and bainitic ferrite in the nano-bainitic steel revealed: (i) the presence of two types of the retained austenite with higher and lower carbon content and (ii) segregation of carbon at the local defects such as dislocations in the bainitic ferrite during the isothermal hold.

Group and team processes in organisations

During recent decades, organisations have shifted towards team-based structures to enhance organisational performance, and research has shifted to investigate these new work structures. This chapter explores team and group process research in organisations. The initial focus of this chapter is to define groups and teams. Types of teams and team development theory will also be briefly discussed. Several theories of group dynamics will then be presented. The input-process-output framework, which explains the relationships between variables in team research, will provide structure to the ensuing discussion of team-related variables, such as individual and team-level characteristics, team and group processes and team performance. A frequent goal of group and team-based research is to understand how to improve team effectiveness and thus performance. Team performance is therefore included in this framework as an important outcome variable. This framework is then extended and a contemporary way of categorising team-based research in organisations is presented. In addition, the potentially important role of moderating variables in team research will also be discussed.

Does gender matter? A one year follow-up of autistic, attention and anxiety symptoms in high-functioning children with autism spectrum disorder

Gender differences in autism spectrum disorder (ASD) symptoms and associated problem behaviours over development may provide clues regarding why more males than females are diagnosed with ASD. Fifty-six high-functioning children with ASD, and 44 typically developing controls, half of the participants female, were assessed at baseline (aged 7–12 years) and one-year later, collecting measures of autism, attention and anxiety symptoms, school placement and support information. Findings indicated no gender differences in autistic symptoms. Males were more hyperactive and received more integration-aide support in mainstream schools, and females were more socially anxious. Overall, similar gender profiles were present across two time points. Lower hyperactivity levels in females might contribute to their under-identification. Implications are discussed using a biopsychosocial model of gender difference.

Sleep in high-functioning children with autism : longitudinal developmental change and associations with behavior problems

Sleep disturbance is common in autism spectrum disorder (ASD), but longitudinal trajectories are poorly defined. This study measured sleep disturbance at baseline and 1 year later examining change over time and associated problem behaviors. Participants were 84 gender-matched children, aged between 7 and 12 years at baseline; 46 children were diagnosed with ASD, and 38 were typically developing (TYP) children. Parent reports on a range of scales were collected. The ASD group had more sleep disturbance than the TYP group. Sleep disturbance decreased over the year in children with ASD, but not in TYP children. Reduced sleep disturbance was associated with improved social ability. Sleep disturbance at baseline predicted later anxiety. Findings indicated different trajectories of sleep disturbance in ASD, and the implications are discussed.

Impact of nanodiffusion on the stacking fault energy in high-strength steels

A key requirement of modern steels – the combination of high strength and high deformability – can best be achieved by enabling a local adaptation of the microstructure during deformation. A local hardening is most efficiently obtained by a modification of the stacking sequence of atomic layers, resulting in the formation of twins or martensite. Combining ab initio calculations with in situ transmission electron microscopy, we show that the ability of a material to incorporate such stacking faults depends on its overall chemical composition and, importantly, the local composition near the defect, which is controlled by nanodiffusion. Specifically, the role of carbon for the stacking fault energy in high-Mn steels is investigated. Consequences for the long-term mechanical properties and the characterisation of these materials are discussed.