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The involvement of left-behind children (LBC) in school bullying has raised concern in China. However, the susceptibility of LBC to engage in bullying is controversial, and comprehensive, representative studies covering the entire country are lacking. The purpose of this study was to evaluate the prevalence and severity of school bullying among LBC. The Chinese National Knowledge Network, WanFang, VIP, PubMed, Web of Science, EMBASE, and EBSCO databases were searched for literature on being left-behind and bullying before April 2022. The effect size was measured by odds ratio (ORs), standard mean difference (SMD), and 95% confidence interval (CI). Random-effects or fixed-effects models were selected for meta-analysis, and subgroup analysis was used to explore the sources of heterogeneity. The meta-analysis included 25 studies of school bullying among LBC and non-LBC (NLBC). The prevalence of bullying perpetration and victimization among LBC were 18.58% (95% CI [3.72%, 33.44%], p <.05) and 40.62% (95% CI [25.47%, 55.78%], p <.05), respectively. Compared with NLBC, the risk of bullying perpetration and victimization among LBC increased 1.97 times (OR = 1.97, 95% CI [1.77, 2.20], p <.05) and 2.17 times (OR = 2.17, 95% CI [1.43, 3.29], p <.05), respectively. The severity of bullying experienced by LBC was higher than that of NLBC (SMD = 0.49, 95% CI [0.20, 0.79], p <.05). The prevalence and severity of school bullying were higher in LBC than in NLBC, and left-behindness was positively associated with school bullying. LBC are a crucial population to protect when developing bullying interventions. [ABSTRACT FROM AUTHOR]

Accurate, detailed, and up-to-date information on cropland extent is crucial for provisioning food security and environmental sustainability. However, because of the complexity of agricultural landscapes and lack of sufficient training samples, it remains challenging to monitor cropland dynamics at high spatial and temporal resolutions across large geographical extents, especially for regions where agricultural land use is changing dramatically. Here we developed a cost-effective annual cropland mapping framework that integrated time-series Landsat satellite imagery, automated training sample generation, as well as machine learning and change detection techniques. We implemented the proposed scheme to a cloud computing platform of Google Earth Engine and generated a novel dataset of China's annual cropland at a 30 m spatial resolution (namely CACD). Results demonstrated that our approach was capable of tracking dynamic cropland changes in different agricultural zones. The pixel-wise F1 scores for annual maps and change maps of CACD were 0.79 ± 0.02 and 0.81, respectively. Further cross-product comparisons, including accuracy assessment, correlations with statistics, and spatial details, highlighted the precision and robustness of CACD compared with other datasets. According to our estimation, from 1986 to 2021, China's total cropland area expanded by 30 300 km 2 (1.79 %), which underwent an increase before 2002 but a general decline between 2002 and 2015, and a slight recovery afterward. Cropland expansion was concentrated in the northwest while the eastern, central, and southern regions experienced substantial cropland loss. In addition, we observed 419 342 km 2 (17.57 %) of croplands that were abandoned at least once during the study period. The consistent, high-resolution data of CACD can support progress toward sustainable agricultural use and food production in various research applications. The full archive of CACD is freely available at 10.5281/zenodo.7936885 (Tu et al., 2023a). [ABSTRACT FROM AUTHOR]

Objective To analyze the status of non-response to hepatitis B vaccine and its related factors in children born to mothers infected with hepatitis B virus (HBV). Methods The children born to mothers with HBV infection reported in Hunan Province from January to December 2022 were selected. All the children received hepatitis B immunoglobulin injection and 3 doses of hepatitis B vaccination and were followed up to 7-12 months of age for detection of hepatitis B surface antigen (HB-sAg) and anti-HBs. Both HBsAg and anti-HBs were negative, indicating that there was no response to hepatitis B vaccine in children. Unconditional binary logistic regression model was used to analyze the related factors of non-response to hepatitis B vaccine in children. Results A total of 9 792 children born to mothers infected with HBV were analyzed. Among 9 792 children, the non-response rate of hepatitis B vaccine was 9.5% (928/9 792). Non-conditional binary Logistic regression analysis showed that the risk of non-response to hepatitis B vaccine in children born to HBeAg-positive mothers was 1.62 times higher than that in children born to HBeAg-negative mothers (OR=1.62, 95% CI: 1.40-1.88). The risk of non-response to hepatitis B vaccine in children with macrosomia (birth weight ≥ 4 000g) was 1.41 times higher than that in children with normal birth weight (OR = 1.41, 95% CI: 1.08-1.85). Maternal antiviral therapy (OR=0.59, 95% CI: 0.48-0.73) and child HepB standard vaccination (OR=0.66, 95% CI: 0.57-0.78) were the protective factors of non-response to hepatitis B vaccine in children. Conclusion The non-response rate of hepatitis B vaccine in children born to HBV infected mothers is high, and it is affected by maternal HBeAg positive, antiviral therapy during pregnancy, birth weight, and standard vaccination. [ABSTRACT FROM AUTHOR]

Rockfalls are major geological hazards threatening prestressed concrete cylinder pipes (PCCPs) in water diversion projects. To accurately assess the impact of large deformation movements of rockfalls on PCCPs, this study utilized the continuous–discontinuous method to investigate the dynamic response of a PCCP under a rockfall. The impact mode of rockfalls, the mechanical characteristics of PCCP, and the nonlinear-contact characteristics between soil and PCCP were considered in this study. The advantages of continuous and discontinuous numerical simulation methods were utilized to establish a continuous and discontinuous coupling model of "tube-soil-rock" considering the interaction of soil and structure. The impact mechanism and process of PCCP under the rockfall were investigated by simulating the rockfall process and analyzing its spatiotemporal evolution. The influence of PCCP under rockfalls with different heights and radii was studied to clarify the effects of these two parameters on the PCCP. Combined with a practical application example of large-scale water transfer projects, there is a tendency of center flattening under static load and dynamic impact load, and the PCCP part directly below the impact point is the most dangerous. This investigation provided a comprehensive understanding of the impact mechanism of the PCCPs under rockfall. The findings of this study have significant implications for the design of the protection engineering of PCCPs and ensuring the safe operation of water diversion projects. [ABSTRACT FROM AUTHOR]

Background: Sensitivity skin (SS) is a common skin disorders, which have a various of clinical manifestation. Facial erythema is common objective symptom of SS. However, the reasons for the occurrence of erythema in sensitive skin are not fully understood. Aims: In this study, we preliminarily explain the possible factors inducing erythema of sensitive skin by evaluating facial erythematous reaction to lactic acid sting test (LAST) and capsaicin test (CAT) in subjects with sensitive skin. Methods: A total of 197 subjects were divided into five groups, that is, normal controls (NC), LAST‐positive (LAST+), both LAST and CAT positive (L+C+), both LAST and CAT negative (L−C−) and CAT‐positive (CAT+). Erythema index (EI), a* value, and tissue viability imaging (TIVI) were measured before and after LAST and CAT, The ΔEI, Δa*, and ΔTIVI before and after LAST and CAT were calculated, and the correlation between the scores of CAT, EI values, a* values, and TIVI values were analyzed to clarify the causes of facial erythema. Results: Our results showed that EI values and a* values were significantly higher in the L+C+ and CAT+ group than in NC group, TIVI values were higher in the L+C+ group than in NC group. ΔEI and Δa* values after LAST did not differ significantly among five groups. However, ΔEI values in L+C+ group were higher than that in L−C− group, while Δa* values were higher in CAT+ group than in NC. Moreover, ΔTIVI values in L+C+ group and CAT+ group were also significantly higher than that in NC group after capsaicin stimulation. CAT scores correlated positively with EI, a* and TIVI values. Conclusion: Our results suggest that sensitive skin subjects with positive CAT are more likely to experience erythema reactions, and vasodilation is more pronounced after capsaicin stimulation. Reducing vascular and neural hyperreactivity could be therapeutic target in management of facial erythema in subjects with sensitive skin. [ABSTRACT FROM AUTHOR]