Search

Objective: Obesity has become a major public health problem worldwide and particularly in China. This study examined the secular trend of overweight and obesity in China over the past 100 years. Methods: Nationwide data from the China Health and Nutrition Survey and the Chinese General Social Survey were used. A generalized binary mixed‐effects model and a weighted quantile sum model were applied. Results: From 1909 to 2021, the prevalence of overweight and obesity remained stable from 1909 to 1944, experienced a smooth increase from 1945 to 1959 followed by a decline between 1960 and 1974, continued to rise after 1975, and peaked in 2003. The prevalence of overweight (obesity) among Chinese adults increased by 2.68 (6.21) times, from 20.65% (3.10%) in 1993 to 55.33% (19.26%) in 2021, and cohorts born during the Chinese Cultural Revolution (1960–1974) exhibited the lowest risk of overweight and obesity, associated with low protein intake and high physical activity. Cohorts born during the Reform and Opening‐Up period (1975–2003) showed a high risk of overweight and obesity related to favorable socioeconomic status and rapid urbanization. Persistent differences by sex and emerging differences by socioeconomic status in overweight and obesity prevalence were captured. Conclusions: Overweight and obesity trends in China have shown a distinctive increasing–decreasing–increasing pattern over the past 100 years. These patterns exhibit unique characteristics and are influenced by discernible social forces. [ABSTRACT FROM AUTHOR]

The phenomenon of flexoelectricity, wherein the generation of electrical polarization results from strain gradients, has garnered significant attention in electromechanics. This phenomenon holds immense potential for diverse applications in nanoelectromechanical systems. Doubly curved shells present a particularly compelling structure for implementing flexoelectric devices, representing the most general scenario. To comprehensively understand the mechanical behavior of nanoscale flexoelectric doubly curved shells, we present a novel analytical model in this study. Our model incorporates a reformulated strain gradient elasticity theory, a modified expression of electric enthalpy density considering Maxwell's self-field gradient, and a moderately thick shell configuration. To further elucidate this model, we establish complete formulations and analytical solutions of static bending and free vibration problems. This study reveals the crucial roles that various parameters such as principal curvature radii, length scale parameters, transverse structural sizes, and the Winkler–Pasternak foundation play in controlling the mechanical behavior of nanoscale flexoelectric doubly curved shells. These theoretical findings offer valuable insights into the design of nanodevices based on the direct flexoelectric effect. [ABSTRACT FROM AUTHOR]

Many scholars focus on China's booming economy and its social impacts, while there is little attention regarding subjective well-being, especially after considering income and social capital. Therefore, the purpose of this paper was to examine the correlations between income, social capital and subjective well-being of western Chinese residents, basing on a representative comprehensive social survey. Several meaningful conclusions are shown below: (1) Western residents in China retain a relatively high degree of subjective well-being on average, and the mean value of subjective well-being for urban residents is slightly higher than that for rural residents; (2) there are regional and group differences in the influence of income and social capital on residents' subjective well-being; and (3), although economic factors play a primary role in subjective well-being, the potential influence of non-economic factors cannot be ignored. This paper attempts to fill the gap in perspective regarding potential correlations between income, social capital, and subjective well-being. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that poor mental health is particularly pronounced among Chinese residents, who are exposed to nearly the worst air pollution worldwide. However, the correlations between air pollutant concentration and mental health have not been consistently reported in previous studies. Methodologically speaking, a sufficiently rigorous design is required to demonstrate the causal relationship between the two factors. In this study, we aimed to infer the causal relationship between air pollutant concentration and mental health. In this panel research, the data were compiled through a combination of statistics from the China Family Panel Study, China Environmental Statistics Yearbook, World Meteorological Association, and China National Bureau of Statistics. Ultimately, this study enrolled 65,326 individuals whose mental health, air pollutant concentration, and other demographic information was available and robust. The RD design of this study utilizes the discontinuous variation in air pollutant concentrations and mental health as one crosses the Huai River boundary, which is an arbitrary heating policy that caused the difference in air pollutant concentrations between the north and south of China. In this study, we found that a 10 μg/m3 increase in air pollutant concentrations (air particulate matter smaller than 10 μm (PM10)) leads to a 4.9-unit decrease in the mental health of the Chinese residents(coeff = 0.49, SD = 0.07, p < 0.05), equivalent to 36% of the average of Chinese residents. In the heterogeneity model, the impairment of mental health by air pollutant concentrations was more pronounced in male residents (coeff = 1.37, SD = 0.10, p < 0.05) compared to female residents (coeff = 0.42, SD = 0.04, p < 0.05) and smokers (compared to non-smokers). The robustness of the results is ensured by changing the RD bandwidth and polynomial order, and by two unique sensitivity analyses. The results indicate that air pollutant concentrations significantly impair the mental health of Chinese residents, which provides empirical evidence supporting the Chinese government's decision to invest more in combating air pollution and ensuring the mental health of Chinese residents. [ABSTRACT FROM AUTHOR]

A new connection measure between the precast concrete (PC) cladding panel and PC frame structure is proposed to realize a new kind of isostatic frame-cladding system. Three full-scale PC wall-frame substructures were tested under the quasi-static load. These substructures included a bare wall-frame specimen, a specimen with a cladding panel that has no opening, and a specimen with a cladding panel that has an opening in it. The damage evolution, failure mode, load-bearing capacity, deformation capacity, and energy dissipation capacity of three specimens were compared. The results indicated that the motions of the cladding panels and the main structures were uncoupled through the relative clearance of the bottom connections, and three specimens exhibited approximately identical failure modes and seismic performance. Thus, the reliability of this new isostatic system was validated. [ABSTRACT FROM AUTHOR]