Qin, Wenzhe
Xu, Lingzhong
Li, Jiajia
Sun, Long
Ding, Gan
Shao, Hui
Xu, Ningze
Funding for this research was provided by:
National Natural Science Foundation of China (71673169, 71673170)
Article History
Received: 15 January 2018
Accepted: 8 May 2018
First Online: 18 May 2018
Ethics approval and consent to participate
: This study was approved by the Academic Research Ethics Committee of Shandong University. All procedures were in accordance with the ethical standards of the Helsinki Declaration. Participants provided informed consent prior to data collection.
: The authors declare that they have no competing interests.
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