Effect of nitrogen application levels on photosynthetic nitrogen distribution and use efficiency in soybean seedling leaves.

BACKGROUND: Nitrogen nutrition is strongly associated with crop growth and development. Nitrogen application level affects leaf size as well as nitrogen content and distribution, and thus affects photosynthetic nitrogen-use efficiency (PNUE) and yield. In this study, soybean varieties "Jinyuan 55" and "Keshan 1" were treated with nitrogen as urea at: N0, 0 kg hm-2; N0.5, 60 kg hm-2; N1, 120 kg hm-2; and N1.5, 180 kg hm-2. We compared the effect of nitrogen level on plant morphology, biomass, photosynthetic physiology, nitrogen distribution, PNUE, and other soybean seedling leaf characteristics. RESULTS: Maximum carboxylation and electron transfer, net photosynthetic rates, and PNUE of both soybean varieties showed initial significant increases with increasing nitrogen application rate and subsequent stabilization. PNUE, carboxylation system components, electron transport components, and non-photosynthetic system distribution ratios in the photosynthetic system increased and subsequently decreased with increased nitrogen application rate. The nitrogen ratio between carboxylation and electron transport systems was positively correlated with PNUE in both soybean varieties. The nitrogen ratio in light-harvesting and non-photosynthetic systems showed a linear negative correlation with PNUE. CONCLUSIONS: Overall, an appropriate nitrogen level maintained a high photosynthetic nitrogen ratio, whereas low- or high-nitrogen conditions increased or decreased the nitrogen ratio in non-photosynthetic and photosynthetic systems, respectively, thus decreasing the PNUE and photosynthetic capacity. Moreover, increased nitrogen application rate led to a decreased nitrogen ratio in the light-harvesting system and an increased nitrogen ratio of electron transport and carboxylation systems. Our results provide a theoretical basis for optimizing leaf nitrogen distribution, determining optimum nitrogen levels, and promoting soybean seedling growth.

The Impact of Transformational Leadership on Physicians' Performance in China: A Cross-Level Mediation Model.

Transformational leadership has been becoming increasingly vital to the provision of high-quality health care, particularly during major public health emergencies. The present study aims to investigate the impact of transformational leadership on physicians' performance and explore the cross-level underlying mechanisms with achievement motivations and coping styles among Chinese physicians. During 2017-2019, 1,527 physicians of 101 departments were recruited from six hospitals in China with a cluster random sampling method. Participants completed several questionnaires regarding their job performance, achievement motivations, coping styles, and transformational leadership. Multilevel mediation effects were tested using cross-level path analysis. The result of this study indicated that transformational leadership was applied well in Chinese medical settings with a score of 101.56 ± 6.42. The hierarchical linear model showed that transformational leadership had a cross-level direct positive effect on physicians' performance (ß = 1.524, p < 0.05). Furthermore, results of cross-level path analyses revealed that transformational leadership contributed to physicians' performance by sequentially influencing achievement motivations first and then coping styles. In addition, the path "transformational leadership → positive coping (PC) style → physicians' performance" showed the strongest cross-level indirect effect. In summary, public health leaders should enhance physicians' performance by promoting individual development, especially achievement motivation and PC style.

The Relationship between Achievement Motivation and Job Performance among Chinese Physicians: A Conditional Process Analysis.

BACKGROUND: To explore the relationship between achievement motivation and job performance among physicians, this study investigated the impacts of different personality traits on job performance among the physicians. METHODS: This cross-sectional study was conducted in 2017 and 1,523 physicians from eight tertiary grade A hospitals in Harbin, China. The type of data collected included the achievement motivation of the physicians, job performance, organizational commitment, personality traits, and other demographic variables. To assess and compare the demographic data, independent t-test and ANOVA were applied. Further, Pearson correlation coefficients were used to evaluate the correlation among the variables. Moderated mediation analysis was performed to test the correlation among the job performance, achievement motivation, organizational commitment, neuroticism, extraversion, openness, agreeableness, and conscientiousness. RESULTS: Achievement motivation directly influences job performance and organizational commitment partially mediates the direct effects of achievement motivation on job performance. Additionally, our findings demonstrated that agreeableness and conscientiousness moderate the strength of the relationships between achievement motivation and job performance mediated by organizational commitment. CONCLUSION: We propose that hospital managers should pay attention to the personal growth of the physicians and improve their organizational commitment via creating a positive working climate and training for career planning and education. Moreover, managers should identify conscientiousness and agreeableness individuals and increase their responsibilities geared towards improving the performance of the organization.