[Objective]To analyze the Yunqi characteristics and periodicity of drought disasters in He'nan Province during 2000 years.[Methods]On the foundation of the drought data of He'nan Province from 221 BC to 1840 AD,a hierarchical classification was conducted,using statistical tools and wavelet analysis to explore the frequency and periodicity of drought in different Yunqi periods.[Results]The most frequent dominant Qi period of drought in He'nan Province was 4th Qi(Taiyin Shitu)(P<0.001),the most of Sitian period was Jueyin Fengmu and Shaoyin Junhuo(P<0.05),the most of Zaiquan period was Shaoyang Xianghuo(P<0.05).At multiple time scales,drought disasters in He'nan Province had 4 quasi-cycles,the 1st to the 4th quasi-cycles were 510,690,300 and 150 years,respectively.[Conclusion]There was a significant difference in the frequency of drought levels in He'nan Province in different periods of dominant Qi,Sitian period and Zaiquan period,which was partly consistent with the Yunqi theory.Besides,the drought disaster in He'nan Province had certain periodic characteristics.

[Objective]To analyze the Yunqi characteristics and periodicity of drought disasters in He'nan Province during 2000 years.[Methods]On the foundation of the drought data of He'nan Province from 221 BC to 1840 AD,a hierarchical classification was conducted,using statistical tools and wavelet analysis to explore the frequency and periodicity of drought in different Yunqi periods.[Results]The most frequent dominant Qi period of drought in He'nan Province was 4th Qi(Taiyin Shitu)(P<0.001),the most of Sitian period was Jueyin Fengmu and Shaoyin Junhuo(P<0.05),the most of Zaiquan period was Shaoyang Xianghuo(P<0.05).At multiple time scales,drought disasters in He'nan Province had 4 quasi-cycles,the 1st to the 4th quasi-cycles were 510,690,300 and 150 years,respectively.[Conclusion]There was a significant difference in the frequency of drought levels in He'nan Province in different periods of dominant Qi,Sitian period and Zaiquan period,which was partly consistent with the Yunqi theory.Besides,the drought disaster in He'nan Province had certain periodic characteristics.

Objective To evaluate the effectiveness and safety of moxibustion for knee osteoarthritis and the methodological quality of systematic reviews(SRs).Methods SRs of moxibustion for knee osteoarthritis were retrieved from CNKI,VIP,Wanfang Data,SinoMed,PubMed,Cochrane Library,Embase and Web of Science was conducted from the establishment of the databases to February 10,2022.AMSTAR 2 was used to assess the methodological quality of SRs.The randomized controlled trials(RCTs)included in these SRs were screened and summarized according to inclusion standard.RevMan 5.4 software was used for Meta-analysis,and GRADE approach was used to assess the certainty of evidence.Results A total of 15 SRs were included.The evaluation results of the AMSTAR 2 showed that the methodological quality was very low for 14 SRs,and low for other 1 SR.A total of 36 RCTs were included.Meta-analysis results showed that compared with the non-steroidal anti-inflammatory drugs(NSAIDs),the moxibustion group had better effects on improvement of WOMAC scores[mean difference(MD)=-5.95;95%confidence interval(CI):-9.25 to-2.65;low quality],relieving pain[MD=-1.26;95%CI:-2.19 to-0.32;very low quality],and improving effective rate[risk ratio(RR)=1.16;95%CI:1.11 to 1.22;low quality].In the moxibustion group,some patients experienced blisters,and most healed in 3 days.Conclusion Moxibustion has advantages in pain reduction and improving effective rate compared with routine Western therapy for knee osteoarthritis.However,well-designed high-quality RCTs are needed for further verification.