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Additional file 1. PRISMA Network Meta-analysis Checklist.

Additional file 2: Table S1. Strategy of this meta-analysis. Table S2. Inclusion and exclusion criteria in each involved study. Table S3. Head-to-head comparisons of incidence of post-dural puncture headache at 48 hours after surgery. Table S4. Head-to-head comparisons of incidence of post-dural puncture headache at 24 hours after surgery. Table S5. Head-to-head comparisons of severity of post-dural puncture headache at 24 hours after surgery. Table S6. Head-to-head comparisons of severity of post-dural puncture headache at 48 hours after surgery. Table S7. Head-to-head comparisons of severity of post-dural puncture headache at 72 hours after surgery. Table S8. Head-to-head comparisons of incidence of postoperative nausea and vomiting. Table S9. Assessment of publication bias for network meta-analysis. Figure S1. Risk of bias summary. Figure S2. Risk of bias graph. Figure S3. Inconsistency test of cumulative incidence of post-dural puncture headache within 7 days. Figure S4. Inconsistency test of incidence of post-dural puncture headache at 24 hours after surgery. Figure S5. Inconsistency test of incidence of post-dural puncture headache at 48 hours after surgery. Figure S6. Inconsistency test of severity of post-dural puncture headache at 24 hours after surgery. Figure S7. Inconsistency test of severity of post-dural puncture headache at 48 hours after surgery. Figure S8. Inconsistency test of severity of post-dural puncture headache at 72 hours after surgery. Figure S9. Inconsistency test of postoperative nausea and vomiting. Figure S10. Funnel plot of the outcomes.

The emergence of big data is breaking the spatial and time limitations of urban waterlogging scenario description. The scenario data of different dimensions (e.g., administrative levels, sectors, granularities, and time) have become highly integrated. Accordingly, a structural and systematic model is needed to represent waterlogging scenarios for more efficient waterlogging response decision-making. In this article, a full-view urban waterlogging scenario is first defined and described from four dimensions. Next a structured representation of scenario element is given based on knowledge unit method. The full-view scenario model is then constructed by extracting the scenario correlation structures between different dimensions (called scenario nesting), i.e., inheritance nesting, feedback nesting, aggregation nesting, and selection nesting. Finally, a real-world case study in Wuhan East Lake High-tech Development Zone, China is evaluated to verify the reasonability of the full-view model. The results show that the proposed model effectively integrates scenario data from different dimensions, which helps generate the complete key scenario information for urban waterlogging decision-making. The full-view scenario model is expected to be applicable for other disasters under big data environment.

This study aims to investigate the characteristics and kinetics of cellulose degradation in oil-impregnated pressboard (OIP) under simultaneous thermal-electrical-mechanical stress accelerated aging. Thus, the multi-stress aging experimental setup is designed and established. OIP multi-stress aging experiments are performed at 130 °C, a DC electric voltage of +6 kV, vibration amplitude of ${10}{-}{50}\ \mu\mathrm{m}$ and vibration frequency of 100–300 Hz. The aging characteristics of pressboard and oil are then measured, including the degree of polymerization and aging by-products (i.e., furfural, moisture, acidity and dissolved gas). Investigations on aging characteristics reveal that thermal stress is still the dominant factor of cellulose degradation, while electrical and mechanical stresses serve as aging acceleration factors. The simultaneous thermal-electrical-mechanical aging of OIP is 10-24% faster than the single thermal aging. Moreover, the kinetics of cellulose degradation is also proposed to predict the bond scission fraction of cellulose with a goodness-of-fitting over 0.97. Finally, the correlations between the parameters in the kinetics of cellulose degradation and mechanical stress reveal that the increase of vibration amplitude generates more weak and amorphous links available for degradation, while the increase of vibration frequency accelerates the reaction rate.

Summary The use of electronic cigarettes (ECs) has grown exponentially over the past few years in China. To obtain the basic information of Chinese EC users, a questionnaire survey was performed to collect the data that describe characteristics of study populations, including daily usage, consumption preference, and risk perception. Volunteers were recruited from Beijing, Shanghai, Guangzhou, and Shenzhen cities of China. In total, among the 511 participants that were included in the analysis, 491 participants (95%) used refillable ECs in the past 3 months. There was a strong association between EC use and traditional cigarette smoking. The majority of participants were dual users and the number of cigarettes smoked decreased with the use of ECs. After using an EC, 20.7% of conventional cigarette smokers attempted to quit smoking. Young people were the primary users across all geographic locations. Specifically, the daily usage for the participants who were 18–39 years old, was higher than those over 40 years old. The majority of participants (59.9%) preferred fruit flavors and 57.8% of them used 1–5 mg/mL nicotine-concentration liquids. Most EC users are motived to quit smoking, and 74.6% claimed that the ECs had no irritant effect on the oral cavity. A total of 50.5% of family members of the study participants reported an improvement of health status while the participants used ECs instead of traditional cigarettes. Overall, the results of this Chinese survey indicate that the per-day cigarette consumption of the dual users decreased whereas their proportion of smokers of low-“tar” cigarettes increased.

Summary With the rapid popularity and increasing numbers of E-cigarette (EC) users, debates on possible health risks and regulation of EC products have attracted attention in public. As a useful means to help assessing the risks of EC consumers, puffing topography studies have come to be an important tool globally. In this paper, a cross-sectional epidemiological study on puffing topography of 511 EC consumers in four cities of China was conducted in January 2018. Data acquisition was based on a questionnaire and a Clinical Research Support System (CReSS) Pocket device for the smoking behavior recording. The results showed that EC consumers in the four cities were mainly young males, most of whom preferred tank systems with zero or low nicotine concentrations (1–5 mg/mL) in the liquid. The average puff volume, puff duration and inter-puff interval (IPI) were 87.2 mL, 1.97 s and 22.0 s, respectively. The factors that may have affected puffing topography such as product type, nicotine concentration, using time, smoking status and battery power were studied. The results suggest that the EC product type and the concentration of nicotine in EC liquids were the main factors that affected the puffing topography of the users. This study was the first study on the puff topography of Chinese EC consumers with a large number of participants. The results may not only help to more deeply understand smoking behavior and to better assess the potential risks for the EC users, but they may also supply useful information for the development of smoking machine regimes for ECs.