Suchergebnisse

AbstractWith the aggravation of congestion, pollution, and other negative externalities generated by continued urbanization, polycentric strategies have gradually become one of the main urban and regional spatial strategies. It remains unclear, however, whether the polycentric structure is conducive to regional coordinated development. This study examines these issues using China's urban agglomerations (UAs) as a sample. The Prolonged Artificial Nighttime‐light Dataset of China (PANDA) was used to measure the polycentric structure. The results of the nonparametric identification of sub‐centers show that almost all of China's UAs exhibit multiple (sub)centers, and the number of (sub)centers in most UAs has increased from 1992 to 2020. Empirical analysis shows that a polycentric structure is beneficial for narrowing regional disparities within the UA, and the narrowing effect of the polycentric structure on regional disparities increases as the distance between centers increases. Furthermore, a polycentric spatial structure is more conducive to the economic growth of small cities in UA, thereby promoting the coordinated development of regions within UA.

We propose and fabricate a linear variable color filter (LVCF) that possesses an enhanced angular tolerance in conjunction with a wide linear filtering range (LFR) by taking advantage of an Ag-TiO2-Ag configuration. The TiO2 cavity is tapered in thickness along the device so that the resonance wavelength can be continuously tuned according to the position. In addition, the metal-dielectric-metal structure is overlaid with a pre-designed graded anti-reflection coating in SiO2 to complete the etalon, thereby maximizing the transmission efficiency across the entire device. The tapered dielectric layers in the proposed filter were fabricated via glancing angle deposition without the help of any mask or moving parts. The center wavelength was scanned from 410 nm to 566 nm, resulting in an LFR of 156 nm, and the overall spectra exhibited an approximate peak transmission of 40% and spectral bandwidth of 68 nm. The angular tolerance was as large as 45°, incurring a fractional wavelength shift below 4.2%. The resonance wavelength was verified to be linearly dependent on the position, providing a linearity beyond 99%. The proposed LVCF will thus be actively utilized in a portable micro-spectrometer and spectral scanning device. ; National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (No. 2016R1A2B2010170); ARC Future Fellowship FT110100853.

The death of child passengers was one of the leading causes of death among children fatally injured on roads in China. Child restraint can effectively protect child passengers. Mandatory child restraint law has been enacted locally in Shanghai and Shenzhen, two major cities in China. In order to understand the public attitude on national legislation in these cities, we conducted a cross-sectional survey with a sample of parents/caregivers with a child aged 0–6 years and own private car from Shanghai and Shenzhen. We used descriptive statistics to describe the distribution of parental awareness and attitudes towards the legislation of child restraint. There were less than 50% parents who were aware of the local legislation of child restraint use. Even though only around 20% of parents were able to respond accurately to the age standard in legislation, among those who knew of the legislation, most of the parents understood that the law had enforcement measures. More than 70% of parents supported the national legislation of child restraint use, and, among them, around 70% supported enforcement and punishment. Thus, the study provided supportive evidence for national legislation, but it also put forward that the work of popularizing law should be strengthened.

OBJECTIVE: To investigate the association between ambient air pollution and stroke morbidity in different subgroups and seasons. METHODS: We performed a time-series analysis based on generalised linear models to study the short-term exposure–response relationships between air pollution and stroke hospitalisations, and conducted subgroup analyses to identify possible sensitive populations. RESULTS: For every 10 µg/m(3) increase in the concentration of air pollutants, across lag 0–3 days, the relative risk of stroke hospitalisation was 1.029 (95% CI 1.013 to 1.045) for PM(2.5), 1.054 (95% CI 1.031 to 1.077) for NO(2) and 1.012 (95% CI 1.002 to 1.022) for O(3). Subgroup analyses showed that statistically significant associations were found in both men and women, middle-aged and older populations, and both cerebral infarction and intracerebral haemorrhage. The seasonal analyses showed that statistically significant associations were found only in the winter. CONCLUSIONS: Our study indicates that short-term exposure to PM(2.5), NO(2) and O(3) may induce stroke morbidity, and the government should take actions to mitigate air pollution and protect sensitive populations.

FUNDING This study was possible by partial financial support from the following Brazilian government agencies: Fundação Araucária, CNPq (433782/2016-1, 310124/2017-4, and 428388/2018-3), CAPES, and FAPESP (2015/50122-0, 2015/07311-7, 2016/16148-5, 2016/23398-8, 2017/13502-5, 2017/18977-1, 2018/03211-6). ACKNOWLEDGMENTS We also wish to thank the Newton Fund, COFAP, and International Visiting Fellowships Scheme of the University of Essex. We also thank IRTG 1740 for support. ; Peer reviewed ; Publisher PDF