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A hybrid method based on the structural equation model (SEM) and a fuzzy cognitive map (FCM) was developed to study the influences of the construction safety risks (CSR) of metro tunnels constructed by the mining method on the project risk (PR). An SEM was used to identify and verify the correlations between the CSR and PR. An FCM was developed adopting the verified standardized causality and path coefficient in the SEM. On this basis, predictive reasoning and diagnostic reasoning were performed in the framework of an FCM to simulate the CSR and PR. The feasibility of the developed method was validated based on the construction project of a metro tunnel in Wuhan City, China. The results show that (1) the cause concept node C2 (tunnel excavation) shows the strongest positive correlation with the target concept node CT (PR). According to their risks, the construction stages are ranked in descending order as C2 (tunnel excavation), C1 (advanced support), C6 (auxiliary measures), C4 (structure waterproofing), C3 (primary support), and C5 (secondary lining). (2) The target concept node CT is most sensitive to changes in the cause concept nodes C2 and C1. (3) Close attention should be paid to key risks, such as X9 (over-excavation and under-excavation) and X8 (unreasonable determination of excavation footage and sequence) in stage C2. Originality and significance: (1) A hybrid method that can simulate the dynamic interaction between the CSR and PR is proposed. (2) A new perspective for the dynamic evaluation of a PR is provided. (3) The method can be used as a decision-making tool for controlling the PR. [ABSTRACT FROM AUTHOR]

Background: Adolescent idiopathic scoliosis (AIS) is the most prevalent type of scoliosis affecting children between the ages of 10–16 years. However, risk factors for AIS, particularly the modifiable ones, are still largely unknown. This study aims to investigate the associations of lifestyle and social environment factors with AIS in Chinese schoolchildren. Methods: This is a matched case–control study based on survey data collected from school-based scoliosis screening program. We used conditional logistic regression models to describe the relative risk of AIS incidence for each variable in the analyses. To examine the independent effect of each factor on developing AIS, a multivariate conditional logistic regression was conducted and odds ratios (ORs) were adjusted for age and other significant variables. Results: Overall, 2538 participants from 49 schools were included in this study, comprising 1269 AIS cases and 1269 controls. Mean age of the study population was 13.4 years ± 1.06 (range 10–18). One thousand five hundred and fifty (61.1%) of the study subjects were girls. After adjusting for other significant factors, inappropriate desk heights, either too low (OR = 1.40, 95% CI 1.04–1.90) or too high (OR = 1.61, 95% CI 1.09–2.38), standing with anterior pelvic tilt (OR = 2.73, 95% CI 1.41–5.28), and sleeping on the right side (OR = 1.38, 95% CI 1.00–1.91), remained associated with elevated AIS risks. In contrast, sitting normally and classroom sitting positions change regularly were associated with lower odds of AIS. The adjusted ORs were 0.69 (95% CI 0.50–0.96) for sitting normally, and 0.72 (95% CI 0.53–0.98) for sitting positions change. Conclusions: This is the first study to address the associations between desk heights and AIS and showed inappropriate desk heights were related to increased AIS risks. To protect school children from developing AIS, stakeholders are advised to consider introducing height-adjustable desks in the class, changing students' sitting positions in the classroom on a regular basis, and implementing educational programs to help students maintain correct sitting postures. [ABSTRACT FROM AUTHOR]

Aiming at the problems of the poor passing capacity of machines and low cleaning rate of seed strip during wheat no-tillage sowing in annual double cropping areas of North China, a spiral discharge anti-blocking and row-sorting device (SDARD) was designed and is reported in this paper. After the straw was cut and chopped by the high-velocity rotating no-till anti-blocking knife group (NAKG), the straw was thrown into the spiral discharging mechanism (SDM) behind the NAKG. The chopped straw was discharged to the non-sowing area to reach the effect of seed strip cleaning through the interaction between the SDM and the row-sorting of straw mechanism (RSM). Based on a theoretical analysis for determining the parameters of crucial components, the quadratic rotation orthogonal combination test method was adopted, and the operating velocity of machines (OVM), the rotary velocity of the spiral shaft (RVSS), and the height of the holding hopper from the ground (HHHG) were selected as the test factors. The straw cleaning rate (SCR) was taken as the test index. The discrete element simulation test was carried out, the regression model of the SCR was established, and parameters optimization and field test were carried out. The results show that the significant order of the three influencing factors on the SCR was HHHG > OVM > RVSS. The optimal combination of operating parameters was that OVM was 5 km/h, RVSS was 80 r/min, and HHHG was 10 mm. Under the optimal parameter combination, the average SCR was 84.49%, which was 15.5% higher than the no-till planter without the device, and the passing capacity of machines was great, which met the agronomic requirements of no-tillage sowing of wheat in annual double cropping areas. This study could provide a reference for the design of no-tillage machines. [ABSTRACT FROM AUTHOR]

Background: It is believed that parents have a great influence on their children's dietary behaviours. However, it is not clear whether parental food patterns are associated with children's nutritional status in China, which includes a vast territory with rich, diverse cultures. The goal of this project is to systematically study the associations between parental food intake and children's overweight and obesity in China, according to children's ages and regional differences.Methods: Based on individual food consumption data from the China Health and Nutrition Survey (CHNS) package in 2011, cross-sectional studies have previously been conducted to analyse the association between different categories of food intake of parents and children. The current study extends this research by directly.Results: Our analysis results show that parental food intake is highly correlated with children's food intake, with the estimated coefficients of most food intake categories being greater than 0.5. Furthermore, this association between parental food intake and children's overweight and obesity is most significant in young children, but it begins to weaken in relation to children aged between 13 and 18. Additionally, the associations between parental food intake and children's overnutrition are more significant in rural areas than they are in urban areas.Conclusions: The association between parental food intake and childhood overweight and obesity is significant, although it varies considerably according to food categories, children's ages and area differences. These results show promise for intervening in the overnutrition of children by controlling household dietary patterns according to children's developmental stages and regional differences. [ABSTRACT FROM AUTHOR]