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Al/SiC composites are excellent candidates to be applied in many area, however, the generation of Al 4 C 3 in Al/SiC composites result in their mechanical properties below expectation. In present work, Al matrix reinforced by SiC composites fabricated by plasma activated sintering (PAS) are investigated. Al/SiC composites synthesized in such a way can be well consolidated under 530 °C with a relative density higher than 99%. The interfacial microstructures of Al/SiC composites prepared under different temperatures are observed to analyze the sintering mechanisms. The results indicate that the oxide impurity on Al and SiC surface is firstly removed by the plasma activation. Due to the interfacial current effect and Peltier effect, local hotspots on the interface of SiC and Al cause the reaction of Al and SiC to form an Al–Si diffusion layer and Si 1-x C. Finally, the Al elements react with Si 1-x C to form Al 4 C 3. In addition, owing to PAS rapid sintering effect, high tensile strength 256 MPa is reached by different strengthening mechanisms. • Al matrix reinforced by SiC composites fabricated by plasma activated sintering (PAS) are firstly investigated. • Al/SiC composites s can be well consolidated under 530 °C with relative density higher than 99% by PAS. • The reaction of Al and SiC to form an Al–Si diffusion layer and Si 1-x C was explained based on the interfacial current effect and Peltier effect. • High tensile strength 256 MPa of Al/SiC composites prepared by PAS is reached by different strengthening mechanism. [ABSTRACT FROM AUTHOR]

Prefrontal cortex plays a vital role in the theory of mind (ToM) and decision making, as shown in functional brain imaging and lesion studies. Considering the primary neuropathology of Parkinson's disease (PD) involving the frontal lobe system, patients with PD are expected to exhibit deficits in ToM and social decision making. The aim of this study was to investigate affective ToM and decision making in patients with PD and healthy controls (HC) in a task assessing affective ToM (Reading the Mind in the Eyes, RME) and two decision-making tasks (Iowa Gambling Task, IGT; Game of Dice Task, GDT). Consistent with previous findings, patients with PD were impaired in the affective ToM task, and when making decisions under ambiguity and in risk situations. The score of emotion recognition in the RME task was negatively correlated with the severity of the disease and positively correlated with the total number of advantageous cards chosen in the IGT. However, the final capital in the GDT was correlated with memory impairment. The present study implies that affective ToM and decision making under ambiguity may share similar neural mechanisms, while decision making under ambiguity and decision making under risk may involve processing within different neural networks. [ABSTRACT FROM AUTHOR]

Abstract: Recent works have suggested an association between the ventromedial prefrontal cortex (VMPC) and social cognition or decision making. The aim of this study is to investigate the theory of mind and decision making in patients with VMPC lesions and in those with dorsolateral prefrontal cortex (DLPC) lesions. Patients with VMPC lesions (n =16) and those with DLPC lesions (n =14) were compared with healthy controls (HC) on faux pas recognition and 2 decision-making tasks. Consistent with previous data, patients with VMPC lesions performed worse on the theory of mind and decision making. Patients with DLPC lesions showed impairments of the theory of mind but performed at control levels on the 2 decision-making tasks. The results supported the view that a separation of function of 2 distinct subregions of the prefrontal cortex is important to the theory of mind and decision making. [Copyright &y& Elsevier]