[Water Environment Characteristics and Water Quality Assessment of Typical Lakes in Inner Mongolia].

Lakes on the Inner Mongolia Plateau, located in the ecologically fragile area of the northern border of China, play a very important role in regulating the regional climate and ecological environment and maintaining biodiversity. Owing to the dual influence of natural factors and human factors, the lake water environment in Inner Mongolia is facing challenges. To clarify the overall water quality of lakes in Inner Mongolia, based on the water quality data of typical lakes in Inner Mongolia in autumn 2019(October-November) and summer 2021(July-August), the temporal and spatial variation in water quality was discussed, and the influence of different indexes on lake water quality was analyzed, and the key factors affecting lake water quality were identified. The results showed as follows:① the spatiotemporal distribution of multiple physicochemical indices of typical lakes in Inner Mongolia were different in the two seasons. On the time scale, the concentration of ammonia nitrogen(NH4+-N) and nitrite nitrogen(NO2--N) were lower in autumn than that in summer, whereas dissolved oxygen(DO) was higher in autumn than that in summer. On the spatial scale, the concentrations of total phosphorus(TP), total nitrogen(TN), chemical oxygen demand(COD), and salinity(Sal) and other indicators in the southwest lakes of Inner Mongolia were higher than those of lakes in the northeast, but the DO index showed the opposite trend. ② Dissolved total solids(TDS) was the main characteristic factor of water quality of typical lakes in Inner Mongolia. ③ The spatiotemporal distribution of lake water quality index(WQI) was significantly different. The lake water quality level decreased with the increase in TDS, and the lake water quality was better in autumn than that in summer.

Study of Building Safety Monitoring by Using Cost-Effective MEMS Accelerometers for Rapid After-Earthquake Assessment with Missing Data.

Suffering from structural deterioration and natural disasters, the resilience of civil structures in the face of extreme loadings inevitably drops, which may lead to catastrophic structural failure and presents great threats to public safety. Earthquake-induced extreme loading is one of the major reasons behind the structural failure of buildings. However, many buildings in earthquake-prone areas of China lack safety monitoring, and prevalent structural health monitoring systems are generally very expensive and complicated for extensive applications. To facilitate cost-effective building-safety monitoring, this study investigates a method using cost-effective MEMS accelerometers for buildings' rapid after-earthquake assessment. First, a parameter analysis of a cost-effective MEMS sensor is conducted to confirm its suitability for building-safety monitoring. Second, different from the existing investigations that tend to use a simplified building model or small-scaled frame structure excited by strong motions in laboratories, this study selects an in-service public building located in a typical earthquake-prone area after an analysis of earthquake risk in China. The building is instrumented with the selected cost-effective MEMS accelerometers, characterized by a low noise level and the capability to capture low-frequency small-amplitude dynamic responses. Furthermore, a rapid after-earthquake assessment scheme is proposed, which systematically includes fast missing data reconstruction, displacement response estimation based on an acceleration response integral, and safety assessment based on the maximum displacement and maximum inter-story drift ratio. Finally, the proposed method is successfully applied to a building-safety assessment by using earthquake-induced building responses suffering from missing data. This study is conducive to the extensive engineering application of MEMS-based cost-effective building monitoring and rapid after-earthquake assessment.

Gender disparity in the associations of overweight/obesity with occupational activity, transport to/from work, leisure-time physical activity, and leisure-time spent sitting in working adults: A cross-sectional study.

BACKGROUND: The associations of occupational activity (OA), commuting, leisure-time physical activity (LTPA), and sitting with overweight/obesity in working adults are controversial. This study explored these factors with the risk of overall and abdominal overweight/obesity in a Chinese working population and whether these associations differ by gender. METHODS: A cross-sectional study was conducted. Data analysis was done among 6739 employed participants. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the studied associations. RESULTS: For male employees, those with heavy OA had a lower overall (OR 0.76; 95% CI, 0.62-0.93) and abdominal (OR 0.76; 95% CI, 0.62-0.93) overweight/obesity risk than those with light OA. Those with LTPA ≥150 min/week had a lower risk of overall (OR 0.73; 95% CI, 0.56-0.96) and abdominal (OR 0.70; 95% CI, 0.53-0.91) overweight/obesity than those with LTPA <150 min/week. Men with leisure-sitting time <2.5 h/day had a significantly lower risk of abdominal overweight/obesity than those sitting ≥4 h/day (OR 0.80; 95% CI, 0.65-0.99). And men who cycled to/from work had a lower risk of overall (OR 0.69; 95% CI, 0.53-0.90) and abdominal overweight/obesity (OR 0.71; 95% CI, 0.54-0.92) than passive transports. However, the above significant associations disappeared among female employees. CONCLUSIONS: Heavy OA, cycling to/from work, and LTPA were associated with lower risk of overall or abdominal overweight/obesity in male employees. Reducing leisure sitting time can also help male employees reduce the risk of abdominal overweight/obesity. More research on gender disparity in the risk of overweight and obesity should be done.