Deep Continental Scientific Drilling Engineering Project in Songliao Basin:progress in Earth Science researcha

The Songke No.2 well (eastern hole)(referred to as Well SK-2),one of the "two wells and four holes"of the Deep Continental Scientific Drilling Engineering Project in the Songliao Basin,is in Anda City, Heilongjiang Province,and was officially completed on May 26,2018.Tlie scientific goals of Well SK-2 cover four aspects:paleoclimate research,resource and energy exploration,primary geological research, and development of deep earth exploration techniques.Since the official commencement of drilling in 2014,the Well SK-2 scientific drilling engineering team has organized and implemented drilling for coring,in situ logging,chemical analysis of core elements,and deep structural exploration around the well.Currently,the following preliminary scientific research progress has been made:4334.81 m in situ core data has been obtained;the centimeter-level high-resolution characterization of the most complete and continuous Cretaceous continental strata ever unearthed has been completed,and the standard profile of continental strata has been initially established;the unconventional natural gas resources and basin-type hot dry rocks in the deep Songliao Basin were found to have good prospects for exploration and development;the climatic evolutionary history of the Cretaceous continental strata was rebuilt for the first time,covering hundreds of thousands to millions of years,and the major events of Cretaceous climate fluctuations have been discovered;all these reveal strong evidence for the subduction and aggregation of paleo-ocean plates,providing a theoretical basis for the re-recognition of the genesis of the Songliao Basin and for deep earth oil and gas exploration.The implementation of the Deep Continental Scientific Drilling Engineering Project in the Songliao Basin is of great significance for exploring the mysteries of the Earth and solving major problems such as those related to the deep energy environment.It is a solid step along the road of "going deep into the Earth".

Impact of body mass index on short-term outcomes of laparoscopic gastrectomy in Asian patients: A meta-analysis

AIM To perform a meta-analysis to investigate the correlation between body mass index(BMI) and the shortterm outcomes of laparoscopic gastrectomy(LG) for gastric cancer(GC) in Asian patients. METHODS The Pub Med, Cochrane, EMBASE, and Web of Science databases were searched for studies that focused on the impact of obesity on the short-term outcomes of LG for GC in Asian patients who were classified into a high BMI(BMI ≥ 25 kg/m^2) or low BMI group(BMI < 25 kg/m^2). The results are expressed using the pooled odds ratio(OR) for binary variables and standard mean difference(SMD) for continuous variables with 95%confidence interval(CI), and were calculated according to the fixed-effects model while heterogeneity was not apparent or a random-effects model while heterogeneity was apparent.RESULTS Nine studies, with a total sample size of 6077, were included in this meta-analysis. Compared with the low BMI group, the high BMI group had longer operative time(SMD = 0.26, 95%CI: 0.21 to 0.32, P < 0.001), greater blood loss(SMD = 0.19, 95%CI: 0.12 to 0.25, P < 0.001), and fewer retrieved lymph nodes(SMD =-0.13, 95%CI: 0.18 to 0.07, P < 0.001). There was no significant difference between the high and low BMI groups in postoperative complications(OR = 1.12, 95%CI: 0.95 to 1.33, P = 0.169), the duration of postoperative hospital stay(SMD = 0.681, 95%CI:-0.05 to 0.07, P = 0.681), postoperative mortality(OR = 1.95, 95%CI: 0.78 to 4.89, P = 0.153), or time to resuming food intake(SMD = 0.00, 95%CI:-0.06 to 0.06, P = 0.973).CONCLUSION Our meta-analysis provides strong evidence that despite being associated with longer operative time, greater blood loss, and fewer retrieved lymph nodes, BMI has no significant impact on the short-term outcomes of LG for GC in Asian patients, including postoperative complications, the duration of postoperative hospital stay, postoperative mortality, and time to resuming food intake. BMI may be a poor risk factor for shortterm outcomes of LG. Other indices should be taken into account.