Authors’ contributions
Xiali Xue conceived the study design and drafted the manuscript. Yuerong Hao and Xinwei Yang supervised the material preparation and data collection. Xiali Xue and Xiaolei Wu performed the statistical analysis and interpreted the results. Xiali Xue, Yuerong Hao, Xinwei Yang, Chaoyang Zhang, Zhongyi Deng, Jie Xu, Xiaolei Wu and Ning Li contributed to the revision. All authors read and approved the final manuscript.