Yucai Li

To evaluate the changes of total phenolic content and antioxidant capacities of five peach cultivars, this work measured them separately in extractable polyphenols and non-extractable polyphenols during the last month of ripening. Total phenolic content was detected using the Folin-Ciocalteau reagent, while total antioxidant activity was detected by DPPH and FRAP assay. In addition, the contribution of extractable polyphenols and non-extractable polyphenols to the total antioxidant activity of peaches was investigated. It is noted that ripening caused a decrease of total phenolic content associated to extractable polyphenols and non-extractable polyphenols by 45.1%–74.6%, 20.7%–41.7%, respectively. Additionally, total antioxidant activity decreased over the ripening period with a high correlation with total phenolic content. Extractable polyphenols contributed more than 50% to the total antioxidant activity, while the non-extractable antioxidants contributed around 31.3%–45.7% (DPPH) or 12.6%–25.4% (FRAP), which suggests that the antioxidant properties of peaches may be undervalued in previous researches.

We analyzed the impact of performance appraisal purpose on employees' proactive behavior, and explored the roles of psychological ownership and self-efficacy as mediators in this relationship. We conducted a survey with 512 employees of enterprises in 4 cities in China. The results of analysis of the data collected showed that an evaluative performance appraisal had a negative influence on the employees' proactive behavior whereas a developmental performance appraisal had a positive influence. Psychological ownership and self-efficacy were found to have an intermediary role between performance appraisal purpose and the employees' proactive behavior. Self-efficacy had a significant positive effect on psychological ownership. Implications of these results for theory and management practice are discussed.