Search

The quality of residential buildings in old urban areas of Beijing is known to be inconsistent, prompting numerous urban renewal projects in the city. This research investigates how building space impacts energy usage and daylighting in courtyard areas of old urban regions in northern China. It also proposes a quick evaluation method for building performance in courtyard spaces, utilizing multi-objective optimization and machine learning classification prediction as a theoretical framework. A study was conducted to gather and organize building space parameters and their corresponding performances using a genetic algorithm. The dataset was then pre-processed and trained using the LightGBM algorithm. The model validation results revealed a recall of 0.9 and an F1-score of 0.8. These scores indicate that the design scheme's performance level can be accurately identified in practical use. The goal of this study is to propose a set of rapid assessment methods for building performance levels in courtyard spaces. These methods can significantly improve the feedback efficiency between design decision and performance assessment, reduce the time wasted in building performance simulation during the architectural design process, and avoid unreasonable renovation and addition in urban renewal. Furthermore, the research method has universality and can be applied to courtyard-shaped buildings in other regions. [ABSTRACT FROM AUTHOR]

The association between CO and chronic obstructive pulmonary disease (COPD) has been widely reported; however, the association among patients with type 2 diabetes mellitus (T2DM) or hypertension has remained largely unknown in China. Over‐dispersed generalized additive model was adopted to quantity the associations between CO and COPD with T2DM or hypertension. Based on principal diagnosis, COPD cases were identified according to the International Classification of Diseases (J44), and a history of T2DM and hypertension was coded as E12 and I10‐15, O10‐15, P29, respectively. A total of 459,258 COPD cases were recorded from 2014 to 2019. Each interquartile range uptick in CO at lag 03 corresponded to 0.21% (95%CI: 0.08%–0.34%), 0.39% (95%CI: 0.13%–0.65%), 0.29% (95%CI: 0.13%–0.45%) and 0.27% (95%CI: 0.12%–0.43%) increment in admissions for COPD, COPD with T2DM, COPD with hypertension and COPD with both T2DM and hypertension, respectively. The effects of CO on COPD with T2DM (Z = 0.77, P = 0.444), COPD with hypertension (Z = 0.19, P = 0.234) and COPD with T2DM and hypertension (Z = 0.61, P = 0.543) were insignificantly higher than that on COPD. Stratification analysis showed that females were more vulnerable than males except for T2DM group (COPD: Z = 3.49, P < 0.001; COPD with T2DM: Z = 0.176, P = 0.079; COPD with hypertension: Z = 2.48, P = 0.013; COPD with both T2DM and hypertension: Z = 2.44, P = 0.014); No statistically significant difference could be found between age groups (COPD: Z = 1.63, P = 0.104; COPD with T2DM: Z = 0.23, P = 0.821; COPD with hypertension: Z = 0.53, P = 0.595; COPD with both T2DM and hypertension: Z = 0.71, P = 0.476); Higher effects appeared in cold seasons than warm seasons on COPD (Z = 0.320, P < 0.001). This study demonstrated an increased risk of COPD with comorbidities related to CO exposure in Beijing. We further provided important information on lag patterns, susceptible subgroups, and sensitive seasons, as well as the characteristics of the exposure‐response curves. Plain Language Summary: The association between CO and chronic obstructive pulmonary disease (COPD) has been widely reported; however, the association among patients with type 2 diabetes mellitus (T2DM) or hypertension has remained largely unknown in China. The aim of this study was to investigate the acute adverse effect of CO on admission of COPD, and COPD with T2DM or hypertension in Beijing, China. Our findings revealed that short‐term exposure to CO significantly increased the risk of COPD and COPD comorbidities admissions. Females were more vulnerable to CO exposure among COPD with comorbidities (expect T2DM group). We found higher effects appeared in cold season than warm season among COPD group. The exposure response relationship showed that there was no significant threshold effect between CO and COPD admission. Key Points: Exposure to CO was associated with an increased risk of chronic obstructive pulmonary disease (COPD) with comorbiditiesFemales were more vulnerable to CO exposure among COPD with comorbiditiesHigher effect appeared in cold season than warm season among COPD group [ABSTRACT FROM AUTHOR]

High fidelity single shot qubit state readout is essential for many quantum information processing protocols. In superconducting quantum circuit, the qubit state is usually determined by detecting the dispersive frequency shift of a microwave cavity from either transmission or reflection. We demonstrate the use of constructive interference between the transmitted and reflected signal to optimize the qubit state readout, with which we find a better resolved state discrimination and an improved qubit readout fidelity. As a simple and convenient approach, our scheme can be combined with other qubit readout methods based on the discrimination of cavity photon states to further improve the qubit state readout. [ABSTRACT FROM AUTHOR]

In the summer of 2017, heavy ozone pollution swamped most of the North China Plain (NCP), with the maximum regional average of daily maximum 8 h ozone concentration (MDA8) reaching almost 120 ppbv. In light of the continuing reduction of anthropogenic emissions in China, the underlying mechanisms for the occurrences of these regional extreme ozone episodes are elucidated from two perspectives: meteorology and biogenic emissions. The significant positive correlation between MDA8 ozone and temperature, which is amplified during heat waves concomitant with stagnant air and no precipitation, supports the crucial role of meteorology in driving high ozone concentrations. We also find that biogenic emissions are enhanced due to factors previously not considered. During the heavy ozone pollution episodes in June 2017, biogenic emissions driven by high vapor pressure deficit (VPD), land cover change and urban landscape yield an extra mean MDA8 ozone of 3.08, 2.79 and 4.74 ppbv, respectively, over the NCP, which together contribute as much to MDA8 ozone as biogenic emissions simulated using the land cover of 2003 and ignoring VPD and urban landscape. In Beijing, the biogenic emission increase due to urban landscape has a comparable effect on MDA8 ozone to the combined effect of high VPD and land cover change between 2003 and 2016. In light of the large effect of urban landscape on biogenic emission and the subsequent ozone formation, the types of trees may be cautiously selected to take into account of the biogenic volatile organic compound (BVOC) emission during the afforestation of cities. This study highlights the vital contributions of heat waves, land cover change and urbanization to the occurrence of extreme ozone episodes, with significant implications for ozone pollution control in a future when heat wave frequency and intensity are projected to increase under global warming. [ABSTRACT FROM AUTHOR]

Urban activities such as transportation and household heating and cooking, contribute to current air pollution and climate change. Electrification policies such as the transition to electric vehicles and the substitution of household coal with electricity, have been implemented at unprecedented levels in the "2 + 26" Cities (i.e., Beijing, Tianjin and 26 other cities in northern China), to reduce air pollutants and CO 2 emissions at the point of use. We employed the Greenhouse gas and Air pollution Interactions and Synergies model to evaluate the impact of vehicle/residential electrification on air quality and CO 2 emissions from 2017 to 2030. Contribution of the end-use sector depends on its relative importance to the emissions of each pollutant and the ability of each sector to reduce their emissions through electrification. Accordingly, electrifying the residential sector improved the air quality in the cities of Shijiazhuang, Xingtai and Baoding, while electrifying the transportation sector generated more local benefits in Beijing and Tianjin. The combination of fleet electrification and coal-to-electricity could reduce the annual mean PM 2.5 concentration by 2.0 μg/m3 (4.4%) throughout the "2 + 26" Cities in 2030. Moreover, more rapid decarbonization of the power sector is needed to maximize the synergies between air quality and climate goals. • Electrification of transport and resident is assessed together. • NO x and VOCs emissions decrease through 2030 with additional EVs. • Electrify residential sector results in PM 2.5 and SO 2 emission reductions. • Depending on which sectors are electrified, spatial patterns of benefits differ. [ABSTRACT FROM AUTHOR]

This paper proposed a new method to describe, compare, and classify the traffic congestion points in Beijing, China, by using the online map data and further revealed the relationship between traffic congestion and land use. The data of the point of interest (POI) and the real-time traffic was extracted from an electronic map of the area in the fourth ring road of Beijing. The POIs were quantified based on the architectural area of the land use; the congestion points were identified based on real-time traffic. Then, the cluster analysis using the attributes of congestion time was conducted to identify the main traffic congestion areas. The result of a linear regression analysis between the congestion time and the land use showed that the influence of the high proportion of commercial land use on the traffic congestion was significant. Also, we considered five types of land use through performing a linear regression analysis between the congestion time and the ratio of four types of land use. The results showed that the reasonable ratio of land use types could efficiently reduce congestion time. This study makes contributions to the policy-making of urban land use. [ABSTRACT FROM AUTHOR]

• Four urban morphological parameters were used to map LCZs, based on open data. • Artificial built types of LCZs covered 11% of the total area in Beijing. • 6% of total area and 58% of all residents were under heat risks in Beijing. • The LCZ of lightweight low-rise suffered the most serious heat risk in Beijing. • 4.0~7.4 million more people will be under heat risks due to future climate change. The "Urban Heat Island" (UHI) effects in cities pose great threats to heat health risks for urban dwellers, but they present great differences inside cities. Local climate zones (LCZs), with distinct surface morphologies and physical structures, can be used to better explore differences of UHI effects inside cities and can also solve their different heat risks there. However, there still existed some gaps to map LCZs and their associated heat risks in cities, due to lack of detailed urban building data. Thus, we focused on mapping LCZs and their associated heat risks in Beijing, based on open data of four urban morphology parameters, including sky view factors, permeable surface fraction, building surface fraction and building height. Seven types of land cover LCZs and eight types of artificial built LCZs were divided. In spite of only 11% of total area, artificial built types of LCZ played vital roles in local economic development. Different types of LCZ were highly related with their urban functions, and most of artificial built LCZs were located in the Capital Functional Core Area and the Urban Functional Development Area. Open low-rise and open midrise were two important artificial built types of LCZ in Beijing, due to their high value of traditional and cultural buildings. Beijing faced serious heat risks in summer, especially for artificial built type LCZs. About 6% of total area and 58% of all residents suffered heat risks in Beijing, and most of them were located in artificial built type of LCZs. Lightweight low-rise suffered the most serious heat risks, and more than 90% of its area and residents were under heat risks. Considering climate change, about 4.0~7.4 million more people would suffer heat risks in future, and the LCZ of compact high-rise was highly sensitive to future climate change in Beijing. Urban morphology, economic function, population density and heat risks existed great differences among various LCZs in Beijing, and thus different strategies should be applied to mitigate heat risks in different LCZs for future city planning. [ABSTRACT FROM AUTHOR]

Extreme temperature-related cardiovascular diseases (CVDs) have become a growing public health concern. However, the impact of temperature on the cause of specific CVDs has not been well studied in the study area. The objective of this study was to assess the impact of temperature on cause-specific cardiovascular hospital admissions in Beijing, China. We obtained data from 172 large general hospitals from the Beijing Public Health Information Center Cardiovascular Case Database and China. Meteorological Administration covering 16 districts in Beijing from 2013 to 2017. We used a time-stratified case crossover design with a distributed lag nonlinear model (DLNM) to derive the impact of temperature on CVD in hospitals back to 27 days on CVD admissions. The temperature data were stratified as cold (extreme and moderate) and hot (moderate and extreme). Within five years (January 2013–December 2017), a total of 460,938 (male 54.9% and female 45.1%) CVD admission cases were reported. The exposure-response relationship for hospitalization was described by a "J" shape for the total and cause-specific. An increase in the six-day moving average temperature from moderate hot (30.2 °C) to extreme hot (36.9 °C) resulted in a significant increase in CVD admissions of 16.1%(95% CI = 12.8%–28.9%). However, the effect of cold temperature exposure on CVD admissions over a lag time of 0–27 days was found to be non significant, with a relative risk of 0.45 (95% CI = 0.378–0.55) for extreme cold (−8.5 °C)and 0.53 (95% CI = 0.47–0.60) for moderate cold (−5.6 °C). The results of this study indicate that exposure to extremely high temperatures is highly associated with an increase in cause-specific CVD admissions. These finding may guide to create and raise awareness of the general population, government and private sectors regarding on the effects of current weather conditions on CVD. • Extreme temperature-related cardiovascular diseases (CVDs) have become a growing public health concern. • Exposure to extreme high temperatures is strongly associated an increase in cause-specific CVD admissions. • Higher susceptibility for the elderly people (≥65 years old) to the extremely high temperature. • Provide suggestions for public health intervention policy making, adjusting strategy planning, and communicating high risks. [ABSTRACT FROM AUTHOR]

Background: Air pollution and cardiovascular disease are increasing problems in China. However, the short-term association between fine particulate matter (PM2.5) and cardiovascular disease (CVD) is not well documented. The purpose of this study is to estimate the short-term effects of PM2.5 on CVD admissions in Beijing, China.Methods: In total, 460,938 electronic hospitalization summary reports for CVD between 2013 and 2017 were obtained. A generalized additive model using a quasi-Poisson distribution was used to investigate the association between exposure to PM2.5 and hospitalizations for total and cause-specific CVD, including coronary heart disease (CHD), atrial fibrillation (AF), and heart failure (HF) after controlling for the season, the day of the week, public holidays, and weather conditions. A stratified analysis was also conducted for age (18-64 and ≥ 65 years), sex and season.Results: For every 10 μg/m3 increase in the PM2.5 concentration from the previous day to the current (lag 0-1) there was a significant increase in total CVD admissions (0.30, 95% CI: 0.20, 0.39%), with a strong association for older adults (aged ≥65 years), CHD (0.34, 95% CI: 0.22 to 0.45%) and AF (0.29, 95% CI, 0.03 to 0.55%). However, the observed increased risk was not statistically significant for HF hospitalizations. The associations in the single-pollutant models were robust to the inclusion of other pollutants in a two-pollutant model. No differences were found after stratification by sex and season.Conclusions: Exposure to PM2.5 increased the risk of hospitalizations from CVD, especially for CHD, and appeared to have more influence in the elderly. Precautions and protective measures and efforts to reduce exposure to PM2.5 should be strengthened, especially for the elderly. [ABSTRACT FROM AUTHOR]

Clarifying the impact of human activities on polycyclic aromatic hydrocarbons (PAHs) in soil can provide a scientific basis to reduce PAHs pollution and formulate control measures to manage soil PAHs pollution, which are important to reduce global warming and support China's implementation of carbon neutrality goals. Here, we characterize the PAHs in 1055 samples of urban soil collected in China from 2000 to 2020. The total concentration of PAHs ranged from 2.75 to 38,865 ng g−1. PAHs concentrations in the Yangtze River Delta (YangtzeD) and Pearl River Delta exhibited an inverted U-shaped curve over time, and PAHs concentrations in Beijing have decreased. Air pollution prevention policies and vehicle emission standards in these regions reduced PAHs in the soil. We measured PAHs in soils of 18 major cities in YangtzeD, representing a typical area. Total concentration of PAHs was 3.88–2153 ng g−1 in YangtzeD, with 40.5%, 36.3%, and 23.2% of PAHs coming from industry and transportation, coal combustion, and biomass combustion, respectively by Positive matrix factorization (PMF) model. To explore how human activities affect the PAH concentrations, we screened three machine learning models and selected SHapley Additive explanation-extreme gradient boosting (XGB-SHAP) as the best model. The results of XGB-SHAP (R2 = 0.64) show that the main human activities affecting PAHs were carbon emissions, population size, and economic development (MAS = 709.1) and industrial waste gas emissions (MAS = 577.1), and these were positively correlated with PAHs. Therefore, effective ways to reduce PAHs may largely rely on industrial co-control. With the prevention and control of air pollution, clean energy, and green and low-carbon development policies constantly being implemented, PAH concentrations will continue to be reduced in the future. [ABSTRACT FROM AUTHOR]

Consecutive measurements of ambient fine particulate matter (PM 2.5) from February 2016 to April 2018 have been performed at four representative sites of Beijing to evaluate the impact of "2 + 26" regional strategies implemented in 2017 for air quality improvement in non-heating period (2017NH) and heating period (2017H). The decrease of PM 2.5 were significant both in 2017NH (20.2% on average) and 2017H (43.7% on average) compared to 2016NH and 2016H, respectively. Eight sources were resolved at each site from the PMF source apportionment including secondary nitrate, traffic, coal combustion, soil dust, road dust, sulfate, biomass/waste burning and industrial process. The results show that the reductions of industrial process, soil dust, and coal combustion were most effective among all sources at each site after the regional strategies implementation with the large reductions in potential source areas. The decrease of coal combustion in 2017NH were larger than 2017H at all sites while that of soil dust and industrial sources were the opposite. Insignificant reduction of coal combustion contribution at the suburban site in the heating period indicated that rural residential coal burning need further control. The industrial source control in the suburbs were least effective compared with other districts. Traffic was the largest contributer at each site and control of traffic emissions were more effective in 2017H than 2017NH. The local nature and increase of biomass/waste burning contributions emphasized the effect of fireworks and bio-fuel use in rural areas and incinerator emissions in urban districts. Secondary nitrate and sulfate were mainly impacted by the regional transport from southern adjacent areas and favorable meteorological conditions played an important part in the PM 2.5 abatements of 2017H. Secondary nitrate became a more major role in the air pollution process because of the larger decrease of sulfate. Finally suggestions for future control are made in this study. • "2 + 26" strategies were evaluated for different functional areas based on more than two years consecutive observation. • The control of coal combustion, industrial process and soil dust were most effective. • Secondary nitrate and road dust became more important in the air pollution process after the regional strategies. • The residential coal, biomass burning and industrial sources in rural areas need stricter control. [ABSTRACT FROM AUTHOR]

The improvement of the environmental efficiency in the power industry is crucial in promoting energy conservation and emission reduction to achieve sustainable development. This study constructs a multi-hierarchy meta-frontier BAM model to measure environmental efficiency considering technological and regional heterogeneity. Using this model, we measure and decompose the environmental efficiency of the power industry in 30 Chinese provinces during 2008–2020. The main results are as follows. (1) Beijing and four other provinces have the highest environmental efficiency among the high-technology group, while Jiangsu and Hainan have the highest environmental efficiency among the medium-technology and low-technology groups, respectively. There are significant differences in environmental efficiency among provinces within each technology group. (2) Regional and technical inefficiencies in the high-technology and medium-technology groups are the main factors influencing inefficiency. However, the inefficiency of the low-technology group is 0.36, while technical inefficiency is 0.34. (3) The environmental efficiency of all three technical groups has improved as a result of technological progress. Environmental efficiency improvement is the largest in the high-technology group but only by 1%. This study extends conventional approaches of environmental efficiency assessment and enhances the comprehension of the operation of the power industry in various Chinese provinces. The research outcomes provide insights for formulating more precise and effective strategies towards the sustainable evolution of China's power sector. • The efficiency is measured by the combined model from a new perspective. • The technology, the management, and the regional heterogeneity are studied. • Each efficiency of each province is ranked as follows, RE > TE > ME. • The environmental efficiency improved in all three technical groups. [ABSTRACT FROM AUTHOR]

Evidence of the short-term effect of SO 2 on hospital admissions for cause-specific cardiovascular diseases (CVD) is still limited. This study aimed to examine the short-term associations between SO 2 and cause-specific CVD hospital admission in Beijing. A total of 460,938 hospitalizations for total CVD were obtained from electronic hospitalization summary reports from 2013 to 2017. A time series analysis was conducted to investigate the association between SO 2 exposure and hospitalizations for total and cause-specific CVD, including coronary heart disease (CHD), atrial fibrillation (AF), and heart failure (HF). Stratified analysis was also conducted by age group (18–64 years and ≥65 years), sex and season. A generalized additive quasi-Poisson model was used to examine the associations between SO 2 and cause-specific CVD after controlling for seasonality, day of the week, public holidays, and weather conditions. We found an almost linear relationship between the exposure to SO 2 and cause-specific CVD admissions. A 10 μg/m3 increase in the two-day average concentration (lag0-1) of SO 2 was associated with an increase of 1.38% (95% CI:0.99%; 1.77%) in hospital admission for total CVD, 1.58% (95% CI: 1.16%; 2%) for CHD and 1.69% (95% CI:0.41%; 2.99%) for AF. Nevertheless, a statistically significant association was not observed for admissions for HF. The observed associations in the single-pollutant models were robust to the inclusion of pollutants in the two-pollutant model, but the estimate was attenuated when adjusting for fine particulate matter (PM 2.5). No difference in the association was observed for the effect modifiers of sex, season and age. A statistically significant association between hospitalizations and SO 2 was observed. The observed association between SO 2 and hospitalization might not be independent of fine particulate matter ( PM 2.5 ), and further studies should be conducted to demonstrate the independent effect of SO 2. • SO 2 has adverse short-term effects of on total and cause-specific cardiovascular disease (CVD) hospital admission. • No difference of association was found for effect modifier of sex, season and age. • The association between SO 2 and cause-specific CVD admission might not be independent of PM 2.5. [ABSTRACT FROM AUTHOR]