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Objective To explore the association between body mass index (BMI) and all-cause mortality among the elderly in Beijing. Methods This analysis was based on the Beijing multidimensional longitudinal study of aging (BLSA), which included 2,090 subjects over 55 years old and was followed-up from 1992 to 2012. BMI-mortality curves were drawn to find the optimal BMI range with the lowest mortality. Cox proportional hazard models were used to obtain the hazard ratios (HRs) for BMI and BMI changes in the overall population and in specific stratified populations. Results During follow-up, 1,164 deaths were recorded; BMI-mortality curve was U-shaped, with the lowest mortality at a BMI of approximately 25 kg/m 2 . After adjusting for gender, age, smoking, drinking and some pre-existing diseases, HRs for underweight, overweight and obesity compared with normal weight were 1.372 (95% CI : 1.154-1.631), 0.767 (95% CI : 0.666-0.884) and 0.871 (95% CI : 0.830-1.246), respectively. HR for BMI drop was 3.245 (95% CI : 0.824-12.772) in the underweight group and 1.892 (95% CI : 0.830-1.246) in the normal weight group, HR for BMI rise was 1.795 (95% CI : 1.243-2.591) in normal weight group and 1.962 (95% CI : 1.202-3.203) in the overweight group. Conclusion Keeping BMI in an overweight status and stable is related to a reduced mortality. [ABSTRACT FROM AUTHOR]

• Using interval-thresholding regression to identify the relationship between cooling, recreational, co-benefit and park size of 349 urban parks in six districts of Beijing. • In all of the urban parks, park size and socioeconomic development being the most positively influential factors. • The TVoEs (threshold value of efficiency) of services in urban parks varied according to socioeconomic development levels, and sustainable planning suggestions were obtained from the intervals' features. Highly urbanized and scarcity of land resource have posed urgent need of threshold analyses of ecological services to achieve optimal ecosystem services efficiency. Whereas previous studies have highlighted the threshold value of efficiency (TVoE) of cooling service, the interval non-linear characteristic of TVoEs of recreational service and co-benefit in urban parks remain unclear, especially identifying the socioeconomic impact on the TVoEs. Taking Beijing as our study area, we identified the dominant impact factors on cooling, recreational services and co-benefit, and assessed the interval variation characteristics of TVoEs of these three services in diversely developed regions. The result indicated that park size and socioeconomic development were dominant factors. And interval-thresholding, which can determine the change interval and trip point, is innovatively used to analyze the relationship between park size and services. This relationship showed different characteristics in two intervals and the TVoE ranges of the parks' co-benefit increased with the improvement of local socioeconomic level. These results can provide quantitative inputs for green space smart planning relating to climate change and public health considerations. [ABSTRACT FROM AUTHOR]

• A multi-criteria approach integrating demand for ecological and cultural services. • We quantified the consumption of green spaces using check-in data. • We applied the demand for ES to optimize the ecological security pattern in central Beijing. A growing number of studies have mapped the demand for ecosystem services (ES). Recently, demand for ES has been broadened to include cultural services in addition to ecological services, especially for urbanized areas. In this study, a multi-criteria approach is proposed that synthesizes the available ecological and cultural services to map the demand for ES: including 1) soil erosion sensitivity, 2) geological hazard sensitivity, 3) water management, 4) vegetation coverage, 5) permanent farmland, 6) accessibility, 7) population density, 8) direct use of green spaces, and 9) cultural heritage. The cultural services demand describes the desire or preference, and consumption or direct use of cultural services, e.g. recreation and cultural heritage. Most studies discussed only the desire or preference for cultural services because of the difficulty quantifying the actual consumption of these cultural services. This research gap was filled using the check-in data collected from WeChat (a major social network in China). Each criterion was assigned a weight so that the ecological services demand, the cultural services demand, and the overall ES demand could be quantified. The results suggest that in general, the mountainous areas, farmlands, and suburban areas have high demand for ecological services while public parks in urban areas show high demand for cultural services. However, the ES demand in the availability of some small green spaces in highly urbanized areas may be higher than that for large green spaces in suburban areas. This multi-criteria analysis is necessary to obtain a comprehensive assessment of ES demand, which will contribute to improving the applicability of ES in real-world decision making, e.g. green space planning and conservation. [ABSTRACT FROM AUTHOR]