ObjectivesThis study aimed to assess the reliability and validity of the Chinese version of the 10-item Perceived Efficacy in Patient–Physician Interaction (PEPPI-10) scale in hospitalized patients with severe knee osteoarthritis in the People’s Republic of China.MethodsBetween January and March 2015, the Chinese versions of PEPPI, self-efficacy for exercise scale, osteoporosis self-efficacy scale, and modified fall efficacy scale were applied to assess 110 severe knee osteoarthritis patients who were hospitalized in the second ward of the department of arthroplasty surgery of Tianjin Hospital.ResultsThe Chinese version of the PEPPI-10 scale had a high coefficient of internal consistency (Cronbach’s α coefficient, 0.907). The score of the Chinese version of PEPPI was weakly correlated with the scores of the Chinese versions of self-efficacy for exercise scale, osteoporosis self-efficacy scale, and modified fall efficacy scale.ConclusionThe Chinese version of the PEPPI-10 scale exhibits sufficient internal consistency and convergent validity in hospitalized patients with severe knee osteoarthritis in the People’s Republic of China.

A novel set of unified constitutive equations has been developed and validated to describe stress relaxation ageing (SRA) behaviour. The model, based on dynamic ageing and power-law creep relations, can predict the stress relaxation, age hardening response and their interactions at different temperatures, through considering the microstructure evolutions (precipitate radius, volume fraction and dislocation density) during SRA. In addition, the model newly incorporates the effects of prior cold work. This model was verified through T74 multi-step SRA experiments for different pre-strain conditions. Excellent agreement was achieved between the predicted and experimental stress relaxation and yield strength evolutions. The evolutions of microinternal variables (e.g. normalised precipitate radius) within the model were calibrated by both the TEM results in this work and the experimental results from the literature. The model provides a valuable tool to predict the mechanical properties, and residual stresses post ageing, thus provides important guidance for designing manufacturing processes, leading to many benefits including reduced scrap rates and financial losses.

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An advanced hybrid joining technology for joining metal and composite is introduced. Protrusions formed on the surface of the metal by electron beam are embedded into carbon fibre reinforced polymer layers and thus forms an integrated joint. The performance of a joint produced using such method was found to be better than traditional joints. In this paper, the properties of two different patterns of protrusions, including a linear pattern and a cylindrical pattern were studied by uniaxial tensile testing of double lap composite structures using digital image correlation. The distributions of strains in the composites tested varied and were found to be influenced by the shape of the protrusions which also resulted in different failure modes. The joints with a linear pattern failed between laminate layers, whereas the joints with a cylindrical pattern fractured at the interface of metal and composite. Furthermore, the tensile properties such as the ultimate tensile strength and elongation to failure of the joint with the linear pattern were around twice the value of the joint with the cylindrical pattern. Consequently, the performance of hybrid joints can be improved significantly by optimising the protrusion pattern