The impact of residential environment on stroke onset and its spatial heterogeneity: A multiscale exploration in Shanghai.

BACKGROUND: Stroke is a worldwide concern due to its high disability and mortality rates, especially in many countries entering ageing societies. This study aims to understand the spatial heterogeneity of stroke onset and residential environment influence scopes from multiscale. METHODS: The 2013 to 2022 spatiotemporal distribution pattern of stroke onset was obtained via out-patient data from a hospital in Shanghai. Then nine residential environmental factors were selected to estimate the association of stroke onset by multiscale geographically weighted regression (MGWR), in three scenarios. RESULTS: Accessibility to pubs/bars (PUB) and building density (BD) were the top two residential environmental factors both for the entire sample and by gender. Stress-related environmental factors have a greater impact on the onset of stroke in men but are limited in scope. The population of elderly people have relevance to environmental variables heterogeneity. The indicators relating to unhealthy food and alcohol suggest that habit-inducing environmental factors have a limited impact on stroke onset, but rather that pre-existing habits play a greater role. CONCLUSIONS: MGWR analyses individual components across multiple bandwidths, revealing geographical disparities in the impact of elements that would otherwise be undetected on a global scale. Environmental factors have a limited impact on the onset of stroke. When society is faced with both heavy ageing and fiscal constraints, some of the blue-green space budgets can be scaled back to invest in more secure facilities.

Spatiotemporal variations of air pollutants based on ground observation and emission sources over 19 Chinese urban agglomerations during 2015-2019.

The "comparative attitude" of urban agglomerations involves multidimensional perspectives such as infrastructure, ecological protection, and air pollution. Based on monitoring station data, comparative studies of multispatial, multitimescale and multiemission pollution sources of air quality on 19 urban agglomerations during the 13th Five-Year Plan period in China were explored by mathematical statistics. The comparison results are all visualized and show that clean air days gradually increased and occurred mainly in summer, especially in South and Southwest China. PM2.5, PM10 and O3 were still the main primary pollutants. PM2.5 is mainly concentrated in December, January and February, and PM10 is mainly concentrated in October-November and March-April. The O3 pollution in the Pearl River Delta and Beibu Gulf urban agglomerations located in the south is mainly concentrated from August to November, which is different from others from May to September. Second, from 2015 to 2019, the increasing rate of O3 concentration in any hour is higher than that of particulate matter (PM). Diurnal trends in O3 concentration in all directions also showed a single peak, with the largest increments that appeared between 13:00 and 16:00, while the spatial distribution of this peak was significantly regional, earlier in the east but later in the west. Third, this analysis indicated that the annual average air quality index (AQI) showed a gradually decreasing trend outward, taking the Central Plain urban agglomeration as the center. The ambient air pollutants are gradually moving southward and mainly concentrated in the Central Plains urban agglomeration from 2015 to 2019. Furthermore, in each urban agglomeration, the cumulative emission of PM2.5 is consisted of the four average emissions, which is approximately 2.5 times of that of PM10, and industries are the main sources of PM2.5, PM10 and VOCs (volatile organic compounds). VOCs and NOX increased in half of the urban agglomerations, which are the reasons for the increase in ozone pollution. The outcomes of this study will provide targeted insights on pollution prevention in urban agglomerations in the future.

Reconsideration of the methodology for estimation of land population carrying capacity in Shanghai metropolis.

How to estimate the urban land carrying capacity (ULCC)? Based on our previous research, this paper made improvements in two aspects: One is to subdivide land use types from four subspaces to seven subspaces (i.e. urban construction, industrial development, agricultural production, rural living, green ecological, other ecological and other subspaces), so as to distinguish more detailed the urban functional and spatial heterogeneities; the other is to reconstructing evaluation index system and estimate both maximum and appropriate population carrying capacities. The results demonstrate as follows: ① There is a significant difference between the population capacities in different types of subspaces. The urban construction and industrial development subspaces are the main carrier of population and economy. The agricultural production and rural living subspaces have low population capacities. The ecological protection and other subspaces have only a very low share of load. ② The appropriate and maximum population capacities of Shanghai metropolis are estimated to be approximately 20-23 million persons and 27-30 million persons, respectively, in 2009. There were 22.1028 million permanent residents of Shanghai in 2009, approaching the limit of the appropriate population capacity but lower than the limit of the maximum population capacity. ③ The methodology for estimation of maximum and appropriate ULCC in this paper not only gives the quantitative range, but also can provide the basis for growth control of urban population.