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The scale of fluctuation (SOF) is the critical parameter to describe the soil spatial variability, which significantly influences the embedded geostructures. Due to the limited data in the horizontal direction, horizontal SOF estimation is relatively challenging and not well studied yet. This paper aims to develop an efficient convolutional neural network (CNN)-based approach for estimating the horizontal SOF by coupling random field and limited CPT data. Two or three columns (i.e. pseudo-CPT) were selected from the simulated 2D random field with prescribed SOF at the same spacing and combined into a two-dimensional matrix as input data to train the CNN model, namely CNN2 and CNN3 models. The dataset of CNN2 and CNN3 models contains 196,670 and 149,420 samples. Results on the training and testing datasets show that the trained CNN model has a good estimation performance as the mean squared error value is less than 0.1 and the correlation coefficient value is larger than 0.99. The effectiveness of trained CNN models was further verified by the new simulated CPT data with untrained SOF from the random field and CPT data from real site in Hollywood, South Carolina. The excellent agreement indicates that the trained CNN model has the ability to capture the horizontal SOF for limited CPT data from the actual project. Finally, the collected CPT data from the Shanghai site was applied for application. The COV of the estimated results of CNN3 and CNN2 models for the Shanghai site is 0.09 and 0.40, indicating the estimation performance of the CNN3 model has less variability than the CNN2 model. The proposed method provides the potential to characterize the soil spatial variability using very limited CPT data. [ABSTRACT FROM AUTHOR]

The geo-structures embedded in the multiple variable strata could be significantly affected by the geological uncertainty. The quantitative evaluation of geological uncertainty and its influence on the structural safety of embedded tunnels are seldom studied in the past. This paper aims to analyse the effect of geological uncertainty on the structural performance of tunnel using the proposed stochastic geological modelling framework. The geological uncertainty is characterized using an improved coupled Markov chain model based on sparse limited boreholes. A mapping approach is presented to solve the mesh asymmetry problem between the simulated strata and the numerical tunnel model. The tunnel structural performance analysis is then conducted based on the combined model considering the geological uncertainty and tunnel structure. A geological uncertainty index (GUI) is proposed to quantitatively evaluate the level of uncertainty of each borehole and the whole site. The effect of the borehole layout scheme on uncertainty evaluation of factor of safety of tunnel structure is investigated by a large number of stratigraphic realizations. Boreholes collected from Norway with relatively more considerable variability and from Shanghai with relatively more minor variability are adopted as case studies to illustrate the proposed probabilistic analysis framework. The results show that the boreholes with larger GUI values and closer to tunnel locations have a greater weight to affect the embedded tunnel structural performance in uncertain geological strata. [ABSTRACT FROM AUTHOR]

Background: Sibship size and structure have a significant association with overweight and obesity in children, but the relationship with thinness has not been fully studied and understood, especially in Asia. This study evaluated the associations among number of siblings, birth order, and childhood thinness and investigated the association of number of younger or older siblings with childhood thinness. Methods: In this study, we performed a population-based cross-sectional study among 84,075 3- to 12-year-old children in Shanghai using multistage stratified cluster random sampling. We defined grades 1, 2, and 3 thinness according to the body mass index cutoff points set by the International Obesity Task Force and used multinomial logistic regression models to estimate the odds ratio (OR) and 95% confidence interval (95% CI). Results: Compared with only children, for boys, children with two or more siblings were more likely to suffer from grade 2 (OR = 1.29, 95% CI 1.02, 1.64) and grade 3 thinness (OR = 1.60, 95% CI 1.07, 2.40); and the youngest child faced a higher risk of grade 2 (OR = 1.44, 95% CI 1.09, 1.90) and grade 3 thinness (OR = 1.53, 95% CI 1.01, 2.33). For girls, children with one sibling were more likely to suffer from grade 1 thinness (OR = 1.22, 95% CI 1.05, 1.42); the oldest child, middle child, and youngest child faced a higher risk of grade 1 (OR = 1.42, 95% CI 1.09, 1.84), grade 2 (OR = 1.26, 95% CI 1.03, 1.54), and grade 1 thinness (OR = 1.87, 95% CI 1.21, 2.88) respectively. There was no statistically significant relationship, however, between a larger number of younger or older siblings and childhood thinness. Conclusions: Regardless of sex, having either siblings or a higher birth order was positively associated with childhood thinness. The present study has suggested that future interventions to prevent childhood thinness should consider family background as an important factor, especially in multi-child-families. [ABSTRACT FROM AUTHOR]

Causes of autism spectrum disorder (ASD) have not been fully understood. Previous studies have linked environmental factors with ASD. However, evidence for the greenness-ASD association is limited, especially in China. To fill this gap, we conducted a matched case-control study to examine the association between greenness and ASD in China. Participants in this study were 84,934 children aged 3−12 years in Shanghai, China, selected using a multi-stage cluster sampling method. ASD cases were firstly screened by questionnaires completed by both children's parents and teachers, and were then confirmed by clinical examinations. Further, 10 healthy controls were randomly selected to match each ASD case by age and sex. The final analyses included 146 ASD cases and 1460 healthy controls. Participants' exposure to greenness before and after birth was assessed by normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) from NASA's Earth Observing System according to their residential locations. We used conditional logistic regression to examine the ASD-greenness association. Per interquartile range (IQR) increase in EVI 500m and NDVI 500m during the year before birth were associated with lower risks of ASD with adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of 0.96 (95%CI: 0.946, 0.975, IQR = 0.074) and 0.937 (95%CI: 0.915, 0.959, IQR = 0.101). Exposure to greenness during the first 3 years after birth was also significantly associated with lower risk of ASD [IQR ORs for EVI 500m and NDVI 500m were 0.935 (95%CI: 0.91, 0.962, IQR = 0.06) and 0.897 (95%CI: 0.861, 0.935, IQR = 0.09), respectively]. Air pollution showed mediation effects on thegreenness-ASD association. Greenness was observed to have stronger beneficial effects on children without historical diseases and term birth. More greenness exposure before and after birth were significantly associated with lower risks of ASD in children. Our results highlight the importance of greenness in urban planning. [Display omitted] • More greenness was associated with lower risks of autism spectrum disorder (ASD). • IQR OR for NDVI 500m before birth associated with ASD were 0.935 (95%CI: 0.91, 0.962). • IQR OR for NDVI 500m after birth associated with ASD were 0.897 (95%CI: 0.861, 0.935). • Greenness may have beneficial effects on ASD children by absorbing air pollutants. [ABSTRACT FROM AUTHOR]

• 1.A well-documented settlement recovery case of shield tunnel is introduced. • 2.Grouting effect on deformation in spatial and temporal dimensions is revealed. • 3.Volume-based grouting efficiency is used to study the deformation characteristics. • 4.Grouting efficiency is low, horizontal convergence increases during the grouting. This paper presents a case study introducing the effect of soil grouting conducted to repair the longitudinal performance of shield tunnel in Shanghai. The maximum of cumulative settlement of the shield tunnel was approximately 15 mm with an averaged increasing rate as high as 0.50 mm/d caused by a new tunneling project underneath. The grouting reinforcement for soils under the invert of tunnel was thus carried out in the distorted section. A full process of deformational responses in terms of settlement and horizontal convergence to the grouting was measured to analyze the influence of grouting on performance recovery in the longitudinal direction. Volume-based grouting efficiency was defined for evaluating the contribution of grouting to structural deformation recovery. The results showed that the settlement is reduced linearly with the increasing of grouting volume. However, horizontal convergence increased during the grouting process and the maximum convergence increment was about 63 % of the magnitude of settlement reduction. Meanwhile, grouting efficiency was found to be relatively low. An average of 9.03 % of the grout volume is contributed to the recovery of settlement trough, while 2.75 % acted on the increase of convergence. Besides, continuous grouting can effectively recover tunnel settlement and remain a safe state. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the prevalence of grade 1, 2 and 3 thinness among Chinese children and to explore their associations with socio-economic status (SES).Design: A population, school-based cross-sectional study using multistage, stratified cluster random sampling. Grade 1, 2 and 3 thinness, overweight, obesity and severe obesity were defined by the International Obesity Task Force BMI cut-offs.Setting: Seven districts of Shanghai, China.Subjects: Chinese children aged 3-12 years (n 84 075).Results: In boys and girls, respectively, the prevalence of grade 1 thinness was 8·89 % and 11·78 %, of grade 2 thinness was 2·80 % and 3·74 %, and of grade 3 thinness was 2·23 % and 2·93 %. Compared with urban children, suburban children had higher prevalence of thinness. Children whose parent had low education had higher prevalence of grade 1, 2 and 3 thinness than those whose parent had high education. The prevalence of grade 2 and 3 thinness, obesity and severe obesity in low-SES children was higher than that in high-SES children, and the prevalence of grade 1 thinness was lower than that in high-SES children. Particular patterns of prevalence of grade 1, 2 and 3 thinness appeared in low-, middle- and high-SES children.Conclusions: The study describes associations of SES with grade 1, 2 and 3 thinness, overweight, obesity and severe obesity in Shanghai children. The patterns of thinness and obesity in Shanghai provide further insights into BMI patterns in mega-cities in developing countries. [ABSTRACT FROM AUTHOR]

Background: China is currently facing a rapid and widespread increase in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). The activities of female sex workers (FSWs) have contributed to the mounting epidemic of HIV/AIDS and other sexually transmitted diseases (STDs). Therefore, this study aimed to assess the HIV/AIDS-related knowledge, attitude and risk behaviors among FSWs operating in Shanghai China.Methods: A cross-sectional study was conducted in five districts of Shanghai, including three suburbs and two downtown locales. We adopted a cluster randomized sampling method to obtain ten geographic sites which consisted of one or more communities/villages proximal to a location where FSWs were accessible. A total of 324 FSWs from 109 Xitou Fang, massage parlors and hair salons who explicitly provided sexual services were enrolled in the study. Each participant completed a questionnaire survey and interview aimed to collect information on the individual's knowledge, attitude, and behaviors associated with risk for HIV/AIDs.Results: The overall correct answer rate of HIV/AIDS-related knowledge was 60.8%, and the knowledge of FSWs from downtown areas was significantly higher than those from suburban areas (P < 0.05). The percentage of FSWs who reported having experiences in commercial sexual services without the use of condoms was 33.6%. Condom slippage or breakage was reported as having occurred at least once by 51.2% of the FSWs. FSWs from suburban areas were found to more often engage in high-risk behaviors, including oral and anal sex, than those from downtown areas (P < 0.001). Many of the FSWs (65.7%) reported having non-client sexual partners (most were identified as boyfriends or husbands); however, condom usage with these partners were lower (34.3%).Conclusions: Based on the findings from our survey, we advise that promotion of HIV/AIDS-related knowledge be targeted towards FSWs in Shanghai, especially those operating in the suburbs. HIV prevention efforts, such as urging constant condom usage with both clients and steady partners, should be sustained and reinforced among the female sex workers population. [ABSTRACT FROM AUTHOR]

Abstract Background The evidence for adverse effects of ambient particulate matter (PM) pollution on mental health is limited. Studies in Western countries suggested higher risk of autism spectrum disorder (ASD) associated with PM air pollution, but no such study has been done in developing countries. Methods A case-control study was performed in Shanghai with a multi-stage random sampling design. Children's exposures to PM 1 , PM 2.5 and PM 10 (particulate matter with aerodynamic diameter < 1 μm, < 2.5 μm and < 10 μm, respectively) during the first three years after birth were estimated with satellite remote sensing data. Conditional logistic regression was used to examine the PM-ASD association. Results In total, 124 ASD cases and 1240 healthy controls were included in this study. The median levels of PM 1 , PM 2.5 and PM 10 exposures during the first three years of life were 48.8 μg/m3, 66.2 μg/m3 and 95.4 μg/m3, respectively, and the interquartile range (IQR) for these three pollutants were 4.8 μg/m3, 3.4 μg/m3 and 4.9 μg/m3, respectively. The adjusted odds ratios (and 95% confidence intervals) of ASD associated with an IQR increase for PM 1 , PM 2.5 and PM 10 were 1.86 (1.09, 3.17), 1.78 (1.14, 2.76) and 1.68 (1.09, 2.59), respectively. Higher ORs of ASD associated with PM pollution were observed in the second and the third year after birth. Conclusions Exposures to PM 1 , PM 2.5 and PM 10 during the first three years of life were associated with the increased risk of ASD and there appeared to be stronger effects of ambient PM pollution on ASD in the second and the third years after birth. Highlights • Post-natal exposure to PM 1 significantly increased the risk of autism (OR = 1.86). • Post-natal exposure to PM 2.5 significantly increased the risk of autism (OR = 1.78). • Stronger associations were observed in the second and the third year after birth. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To investigate the prevalence of obesity in a Chinese community according to the World Health Organization recommended criteria for Asians in 2000 based on body mass index (BMI) and waist circumference (WC), and to examine the associations between obesity and the risk of hypertension and type 2 diabetes among adults age 40 years and over in Shanghai, China. Methods: A population-based survey was conducted in Youyi Community in Shanghai. Five thousand seventy-one subjects (1917 men and 3154 women) were included in this study. Standard questionnaires were used to collect baseline data of participants. Body weight, height, WC, blood pressure, and glucose in the blood were measured. Results: The prevalence of general obesity was 44.6% (46.4% for men and 43.6% for women) according to BMI and 36.1% (25.5% for men and 42.6% for women) for central obesity according to WC. The prevalence of obesity I was higher in men (41.6%) than in women (36.2%; χ2 =14.8, P <0.05), although the rate was higher in women than in men for obesity II (7.4% versus 4.8%, χ2 =13.6, P <0.01) or central obesity (42.6% versus 25.5%, χ2 =152.1, P <0.01). Odds ratios of hypertension and type 2 diabetes were significantly higher in the obesity group compared with either the group with BMI 18.5–<23.0kg/m2 or the group with WC<90cm for men or <80cm for women. Conclusions: According to the criteria of obesity for Asians, the prevalence of obesity among Chinese adults age 40 years and over in Shanghai is high. Subjects with obesity have a significantly higher risk of hypertension and type 2 diabetes. [Copyright &y& Elsevier]

The inherent spatial variability of soil properties is the main sauces of uncertainties in the site investigation, and it is commonly characterized using random field theory. In the context of random fields, the scale of fluctuation (SOF) is a significant parameter to reflect the spatial correlation between the two points of soil properties. However, it is challenging to estimate the SOF value accurately, especially when there are only limited project-specific test results, such as cone penetration test (CPT) data. This study aims to develop a convolutional neural network (CNN) approach to estimate the vertical SOF based on limited CPT data. The CNN model was constructed and trained by the simulated 15,000 CPT samples using random fields. The results show that the CNN model has excellent performance for estimating vertical SOF. The approach is validated and illustrated through newly simulated CPT data, eight real CPT data obtained from the literature, and three CPT data collected from the Shanghai site. The proposed scale factor method can solve the mismatch between the actual CPT depth and the required depth for input data of the CNN model, making the CNN model more widely applicable. • A CNN approach is developed to estimate vertical SOF for soil properties. • The approach is validated and illustrated using both real and simulated data. • The proposed scale factor method can make CNN model more widely applicable. • Promising estimation performance is achieved. [ABSTRACT FROM AUTHOR]