Fei Guo1, Jun Li2, Kun Chen3, Rongquan Tang3, Lu Zhou3. 1. Department of Forensic Medicine, National Police University of China, No. 83, Tawan Street, Huanggu District, Shenyang, Liaoning 110854, China. Electronic address: nevergfaye@163.com. 2. Department of Forensic Medicine, National Police University of China, No. 83, Tawan Street, Huanggu District, Shenyang, Liaoning 110854, China. 3. Institute of Forensic Science, Public Security Bureau of Laibin City, No. 320, North 2nd Road, Xingbin District, Laibin, Guangxi Zhuang Autonomous Region 546100, China.