[Driving Forces and Mitigation Potential of CO2 Emissions for Ship Transportation in Guangdong Province, China].

Ships are important sources of carbon dioxide (CO2) emissions in Guangdong Province. The study of historical evolutions, drivers, and projected pathways of CO2 emissions can provide scientific support for the development of carbon peaking and carbon neutral strategies in Guangdong Province. The emission factor method, log-average index (LMDI) method, and scenario analysis method were adopted to estimate CO2 emissions, identify the drivers, and explore the mitigation potential from ships in Guangdong Province, separately. The results showed that:① CO2 emissions from ships in Guangdong Province increased from 3.319 4 million tons to 6.392 9 million tons from 2006 to 2020, with dry bulk carriers and container ships being the main ship types causing the increase in emissions. ② The positive drivers of CO2 emissions from ships in Guangdong Province from 2006 to 2020 were transport intensity (51%) and economic factors (49%), and the negative drivers were energy intensity (93%) and cargo class structure (7%). ③ Carbon peaking would not be reached by 2030 if Guangdong Province maintains the current policy (baseline scenario) for ship transportation. ④ Simultaneous optimization of the energy structure and promotion of the energy intensity (energy-efficient and low-carbon scenario) had a 56.51% potential to reduce CO2 emissions from ships compared to the baseline scenario. This can provide scientific support for Guangdong Province to develop a carbon peaking and carbon neutral control strategy for the shipping industry.

Comparison of emergency cholecystectomy and delayed cholecystectomy after percutaneous transhepatic gallbladder drainage in patients with acute cholecystitis: a systematic review and meta-analysis.

Laparoscopic cholecystectomy and percutaneous transhepatic gallbladder drainage (PTGBD) are common treatments for patients with acute cholecystitis. However, the safety and efficacy of emergency laparoscopic cholecystectomy (ELC) and delayed laparoscopic cholecystectomy (DLC) after PTGBD in patients with acute cholecystitis remain unclear. The PubMed, EMBASE, and Cochrane Library databases were searched through October 2019. The quality of the included nonrandomized studies was assessed using the Methodological Index for Nonrandomized Studies (MINORS). The meta-analysis was performed using STATA version 14.2. A random-effects model was used to calculate the outcomes. A total of fifteen studies involving 1780 patients with acute cholecystitis were included in the meta-analysis. DLC after PTGBD was associated with a shorter operative time (SMD - 0.51; 95% CI - 0.89 to - 0.13; P = 0.008), a lower conversion rate (RR 0.43; 95% CI 0.26 to 0.69; P = 0.001), less intraoperative blood loss (SMD - 0.59; 95% CI - 0.96 to - 0.22; P = 0.002) and longer time of total hospital stay compared to ELC (SMD 0.91; 95% CI 0.57-1.24; P < 0.001). There was no difference in the postoperative complications (RR 0.68; 95% CI 0.48-0.97; P = 0.035), biliary leakage (RR 0.65; 95% CI 0.34-1.22; P = 0.175) or mortality (RR 1.04; 95% CI 0.39-2.80; P = 0.933). Compared to ELC, DLC after PTGBD had the advantages of a shorter operative time, a lower conversion rate and less intraoperative blood loss.