Heterogeneity and Decomposition Analysis of Manufacturing Carbon Dioxide Emissions in China's Post-Industrial Innovative Megacity Shenzhen.

Effectively reducing manufacturing carbon dioxide (CO2) emissions is a vital strategy for China to curb its rapidly rising carbon footprint. Features of such a reduction in manufacturing include an increase in the share of high-tech manufacturing and optimization of the energy consumption structure. This study aims to analyze the case of Shenzhen, a unique post-industrial innovative manufacturing megacity, for its leading experience in China's manufacturing transition. Disaggregated manufacturing emissions data of Shenzhen, including 27 sub-sectors in four categories, were collected, and driving factors were identified by the logarithmic mean Divisia index (LMDI) method. The results suggest that: (1) CO2 emissions from Shenzhen's manufacturing show a phased difference between 2008-2012 and 2012-2020. CO2 emissions embodied in electricity consumption have increased by over 30% in the former period and have remained stable at a high level of over 90%. (2) Significant heterogeneity of CO2 emissions in various manufacturing sectors is revealed, with the largest emissions sources being factories that make communication equipment, computers, and other electronic equipment. (3) Lower carbon intensity is the primary factor in reducing CO2 emissions, while the economic activity effect of manufacturing possesses a stimulating impact. (4) The marginal impact of restructuring on CO2 emissions is insignificant since the manufacturing and energy structures of Shenzhen have been upgraded to a low carbon level. Therefore, strengthening the power saving management and improving the energy efficiency of the manufacturing, rather than optimizing the manufacturing and final energy structures, will be a necessary potential solution to the problem of how to reduce CO2 emissions in Shenzhen's manufacturing.

China's provincial process CO2 emissions from cement production during 1993-2019.

Carbon dioxide (CO2) emissions from China's cement production process have increased rapidly in recent decades, comprising the second-largest source of CO2 emissions in the country, next only to fossil fuel combustion. However, there used to lack high-quality data to estimate provincial process-related CO2 emissions from the cement industry of China. It has been recognised that many previous publications have adopted cement-based accounting methods or national average emission factors to estimate them. This study assembles fundamental provincial clinker production data and provincial clinker emission factors from multiple official statistics sources, following the Intergovernmental Panel on Climate Change (IPCC) methodology (A clinker-based estimation methodology), to develop a high-quality panel dataset of China's provincial process-related cement emissions during 1993-2019. In 2019, the gross cement process emissions of China amounted to 818.2 Mt CO2, and the cumulative emissions between 1993-2019 were estimated to be approximately 12.5 Gt CO2. There are significant differences in provincial process-related CO2 emissions. The dataset is crucial to provincial cement process emission characterisation and emissions reduction policy-making in China.

Physical activity and its association with cognitive function in middle- and older-aged Chinese: Evidence from China Health and Retirement Longitudinal Study, 2015.

BACKGROUND: Despite the known benefits of physical activity (PA) on cognitive function, the specific dimensions of PA that are associated with cognitive function require further research in China. We aimed to explore the patterns of PA and elucidate the association between cognitive function and different levels of PA in middle aged and elderly Chinese individuals. METHODS: A total of 8,023 participants aged ≥45 years were selected from the China Health and Retirement Longitudinal Study. The PA intensity was categorized as: vigorous (VPA), moderate (MPA), and light (LPA). The associations of frequency and duration of PA at different intensities with cognitive function were examined using the multivariable linear model, including all respondents and urban-rural subgroups. RESULTS: Compared with those who had no VPA, those who spent 6-7 days/week (ß = -0.59, 95% CI: -1.10, -0.09) or more than 240 min/each time on VPA had poorer cognitive function among rural respondents, whereas cognitive function was only associated with the duration in urban respondents. Compared with those who had no MPA, the rural respondents who spent 1-5 days/week (ß = 0.66, 95% CI: 0.12, 1.20) or 6-7days/week, or spent < 2 hours each time had better cognitive function. For LPA, frequency and duration were both positively associated with cognitive function, and were observed in both rural and urban sub-groups. CONCLUSIONS: The association between cognitive function and PA depended largely on the intensity and area. Cultural context and geographical differences should be considered when designing intervention policies. HighlightsThe prevalence of PA increased as the intensity decreased and was higher in rural respondents than in urban respondents.Cognitive function was related to the intensity, frequency, and duration of PA. However, the magnitude and direction of the association depended mainly on the intensity and geographical area.VPA was negatively correlated with cognitive function, and the association was significant only in rural respondents. However, MPA and LPA were positively correlated with cognitive function, while the association between LPA and cognitive function was significant in both rural and urban respondents.

Intergenerational Ties in Context: Association between Caring for Grandchildren and Cognitive Function in Middle-Aged and Older Chinese.

Grandchild caregiving is suggested to improve the elderly's cognitive function, but the specific relationship remains under-investigated. Considering gender disparity, this study aimed to understand the relationship between grandchild caregiving and cognition. In total, 7236 Chinese residents (≥45 years old) were selected from the 2015 China Health and Retirement Longitudinal Study (CHARLS). The China Health and Retirement Longitudinal Study Harmonized Cognitive Assessment Protocol (CHARLS-HCAP) was used to measure cognition. Grandparenting was measured from three dimensions: caregiving frequency, intensity, and the number of grandchildren cared for. The relationship was examined by multivariate linear regression, with age as a moderator. The results showed that the majority of respondents provided care to their grandchildren, especially grandmothers. Grandchild caregiving was positively associated with cognition (ß = 0.686, 95% CI = 0.334-1.038), especially in the older-aged group. Moderate, not regular grandparenting, or caring for one grandchild was more positively associated with cognitive function. However, intensive and regular grandchild care was significantly associated with cognition only in men. No moderating effects of age were found in women. The study confirmed that moderate intensity and frequency of caregiving was related to better cognitive function in middle-aged and older Chinese population, whereas cultural context and gender differences could be considered when designing targeted policies.

Association between social participation and cognitive function among middle- and old-aged Chinese: A fixed-effects analysis.

BACKGROUND: Social Participation (SP) is known to benefit cognitive function. However, whether the positive relationship holds across different types of SP and dimensions of cognitive function, and whether the statement stays true in middle- and old-aged Chinese have not been investigated. The present study aimed to understand the current patterns of SP and cognitive function in China's context, and therefore, explore the associations between cognitive function and SP at different levels from various aspects. METHODS: A total of 7973 community residents aged 45 years and older were selected from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2015). A fixed-effects analysis was used to explore the association between changes in SP (diversity, frequency, and type) and that in cognitive function (memory and mental status) over a four-year period. RESULTS: Changing from no SP to more variety (ß = 0.377, 95% confidence interval (CI) = 0.192-0.562 for 1 type, ß = 0.703, 95% CI = 0.470-0.937 for ≥2 types) or higher frequency (ß = 0.235, 95% CI = 0.007-0.462 for not regularly, ß = 0.604, 95% CI = 0.411-0.798) of SP was associated with improvements in cognitive function. Playing mah-jong and using Internet were associated with improved memory but not with mental status. Sports and volunteering were associated with improved mental status but not with memory. The same pattern was observed in men and in women. CONCLUSIONS: The study confirmed that more diversity and higher frequency of SP was associated with improved cognitive function, whereas reminded policymakers to consider cultural context when developing target strategies to improve cognitive function.

Variety, frequency, and type of Internet use and its association with risk of depression in middle- and older-aged Chinese: A cross-sectional study.

BACKGROUND: Internet use is beneficial to mental health has been acknowledged, but its specific patterns await further investigation in China's context of urban-rural disparity. Therefore, we aimed to understand the patterns of Internet use and measure their associations with risk of depression in China from three dimensions: variety, frequency and type. METHODS: We selected 18,492 urban and rural Chinses respondents aged 45 years and older from China Health and Retirement Longitudinal Study (CHARLS) 2015 dataset. Risk of depression was measured by 10-item Centre for Epidemiologic Studies (CES-D 10). Internet use was measured from three dimensions: variety, frequency and type, whereas its relationship with risk of depression was examined by multivariate logistic regression model. RESULTS: In the whole sample, 67.2% of respondents had no risk of depression, and approximately 7% used Internet, which was inversely associated with risk of depression (AOR=0.617, 95% CI=0.444, 0.858). Rural respondents had higher risk of depression (37.1% VS 26.2%) and lower prevalence of Internet use (2.6% VS 13%). Among rural respondents, using Internet occasionally (AOR=0.338; 95% CI=0.130, 0.881), using one type of device (AOR=0.293; 95% CI=0.113, 0.760), especially mobile phone (AOR=0.427; 95% CI=0.187, 0.978) were associated with lower odds of depression. No significant associations were observed in urban respondents. LIMITATIONS: The causal relationship between variables awaits further investigation with a longitudinal design. CONCLUSION: Internet use was negatively associated with risks of depression, especially in rural but not in urban participants. Rural-urban disparities should be considered when designing strategies to encourage moderate Internet use.