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To explore the genotyping characteristics of human fecal Escherichia coli (E. coli) and the relationships between antibiotic resistance genes (ARGs) and multidrug resistance (MDR) of E. coli in Miyun District, Beijing, an area with high incidence of infectious diarrheal cases but no related data. Over a period of 3 years, 94 E. coli strains were isolated from fecal samples collected from Miyun District Hospital, a surveillance hospital of the National Pathogen Identification Network. The antibiotic susceptibility of the isolates was determined by the broth microdilution method. ARGs, multilocus sequence typing (MLST), and polymorphism trees were analyzed using whole-genome sequencing data (WGS). This study revealed that 68.09% of the isolates had MDR, prevalent and distributed in different clades, with a relatively high rate and low pathogenicity. There was no difference in MDR between the diarrheal (49/70) and healthy groups (15/24). We developed a random forest (RF) prediction model of TEM.1 + baeR + mphA + mphB + QnrS1 + AAC.3-IId to identify MDR status, highlighting its potential for early resistance identification. The causes of MDR are likely mobile units transmitting the ARGs. In the future, we will continue to strengthen the monitoring of ARGs and MDR, and increase the number of strains to further verify the accuracy of the MDR markers. [ABSTRACT FROM AUTHOR]

Clostridium perfringens is an important zoonotic pathogen. This study was designed to explore the prevalence and toxin types of C. perfringens in retail beef collected from Beijing, China. Among 221 beef samples collected, 53 samples were positive for C. perfringens, resulting in the average prevalence as 23.98%. By toxin gene-based typing, the most C. perfringens strains belong to type A (96.23%, 51/53), only 2 strains were identified as type D. By a multi-locus sequence typing (MLST)-based analysis, a total of 36 sequence types (STs) were detected, and the most STs (n=30) represented just a single strain. These finding suggested that the prevalence of C. perfringens in retail beef in Beijing was considerably high and these bacteria displayed extreme diversity in genetics. [ABSTRACT FROM AUTHOR]

Nitrate (NO 3 −) is a key component of secondary inorganic aerosols and PM 2.5. However, the contributions of nitrogen oxides (NO x) emission sources to NO 3 − in PM 2.5 remain poorly constrained. This study measured nitrogen (N) isotopes of NO 3 − (hereafter as δ15N-NO 3 -) in PM 2.5 collected at Beijing in 2014. We observed that δ15N-NO 3 - values in PM 2.5 (−2.3‰ − 19.7‰; 7.3 ± 5.4‰ annually) were significantly higher in winter (11.9 ± 4.4‰) than in summer (2.2 ± 2.5‰). The δ15N differences between source NO x and NO 3 − in PM 2.5 (hereafter as Δ values) were estimated by a computation module as 7.8 ± 2.2‰ − 10.4 ± 1.6‰ (8.8 ± 2.4‰). Using the Δ values and δ15N values of NO x from major fossil (coal combustion, vehicle exhausts) and non-fossil sources (biomass burning, microbial N cycle), contributions of major NO x sources to NO 3 − in PM 2.5 were further estimated by the SIAR model. We found that seasonal variations of δ15N-NO 3 - values in PM 2.5 of Beijing were mainly caused by those of NO x contributions from coal combustion (38 ± 10% in winter, 20 ± 9% in summer). Annually, NO x from coal combustion, vehicle exhausts, biomass burning, and microbial N cycle contributed 28 ± 12%, 29 ± 17%, 27 ± 15%, and 16 ± 7% to NO 3 − in PM 2.5 , respectively, showing actually comparable contributions between non-fossil NO x (43 ± 16%) and fossil NO x (57 ± 21%). These results are useful for planning the reduction of NO x emissions in city environments and for elucidating relationships between regional NO x emissions and atmospheric NO 3 − pollution or deposition. Image 1 • δ15N-NO 3 - values of PM 2.5 in Beijing were higher in winter than in summer. • Seasonal δ15N-NO 3 - variations of PM 2.5 were mainly caused by those of NO x emission from coal combustion. • Fossil and non-fossil NO x sources contributed equally to NO 3 − of PM 2.5 in Beijing. Isotope partitioning of major nitrate sources in PM 2.5 [ABSTRACT FROM AUTHOR]

The impact of COVID-19 is sought to be investigated on the sport legacy of the Beijing 2022 Olympic Winter Games through employing the Legacy Plan of the BOCOG 2022 as the analytic protocol of the qualitative data, which is collected through 26 interviews with personnel from the General Administration of Sport, BOCOG 2022, etc. It is revealed that the negative impact of the pandemic is exerted through two means: directly by the pandemic per se; indirectly by the postponement of the Tokyo 2020 Olympic Summer Games. Moreover, the positive impact could be recognised as consequences of: new knowledge gained through the alternation of working patterns of stakeholders; the additionality of the negative impact of the pandemic; the new relationship forged among stakeholders of the Beijing 2022 Winter Olympics. It is concluded with recommendations for controlling the pandemic and easing its negative impact during the preparation stage of the Games and for the development of the legacy of the 2022 Winter Olympics in the pandemic circumstance. [ABSTRACT FROM AUTHOR]

Pumping wells (PWs) lie at the core of agricultural irrigation infrastructure, and their spatial configuration is of great significance for the scientific management of regional agriculture and rational use of water resources. To solve the problems of unreasonable and unscientific spatial allocation of regional agricultural irrigation PWs, this paper proposes a new strategy for updating agricultural irrigation PWs based on a spatial decision model, using Songzhuang Town, Tongzhou District, Beijing as a case study. The model utilizes constraints based on local factors such as actual land use, and proposes a novel feasible solution strategy that combines random local search and abrupt jumps to increase the probability that feasible solutions will be found, addressing the performance issues of simulated annealing algorithms, influence of initial values, and parameter sensitivity. Finally, we used the proposed method to perform updated decision analysis on the spatial configuration of PWs in the study area. The results showed that most of the crops in the study area lack irrigation, and the currently available PWs cannot meet the needs for irrigation. The new PWs added based on this decision method can be more evenly distributed within the predefined optimization unit. The proposed number of PWs to be added is 166, the density of PWs is 0.04/ha, and the crop area covered by the PWs is 3350.43 ha. In contrast to the previous PW layout, the optimized PW configuration can meet the irrigation needs of residents, indicating that the new method proposed in this paper has good potential for extension and application. [Display omitted] • A new decision-making method for renewal of agricultural irrigation PWs was proposed. • The maximum unit crop area can be covered when the buffer zone radius was set to 166 m. • The optimal spacing of agricultural irrigation wells was 332 m. • The scheme alleviated the problem of insufficient water for agricultural irrigation. • The method has popularization potential for regional agricultural water management. [ABSTRACT FROM AUTHOR]

It is of great significance to understand how urbanization and greenspace areas gradient affect urban plant biodiversity for urban renewal and planning toward urban biodiversity conservation. However, the factors affecting plant diversity under rapid urbanization remain unknown in many cities. To this end,702 vegetation sampling plots from 219 2 km × 2 km grids were selected to explore the urban plant biodiversity variation within two perpendicular 10 km width transects running across the urban center in north-south and east-west directions within the 6th ring road in Beijing, China. Impervious surface area (ISA) and Greenspace area (GSA) of each grid were interpreted from high resolution remote sensing images. ISA mainly includes road surface, asphalt, and buildings, and GSA includes tree, shrub and herb canopy. A total of 396 plant species were recorded, including 95 tree species, 87 shrub species, and 214 herb species. The 396 species belonged to 298 genus and 93 families. We found that woody plant diversity, tree size attributes (DBH, height, canopy breadth), and total plant taxa increased significantly with increased urbanization while herb plant diversity decreased significantly. However, the GSA has no significant impact on plant diversity and taxa. We further found the higher woody plant diversity and lower herb plant diversity in ISA's with a percentage > 50%, and in the ISA percentage < 50% with larger ISA and GSA area (ISA+GSA percentages (i.e., >80%). ISA and GSA can thus be predictive factors for estimating urban plant diversity, which was related to urban planning and different greening decision-makers. The results of this study have important implications for further understanding how current urbanization factors affect plant diversity, which could implement better scientific urban planning to conserve and restore urban biodiversity in many cities around the world. [ABSTRACT FROM AUTHOR]

The near-to-nature urban forestry concept and practices are widely recognized for urban greening, urban ecosystem restoration, urban greenspace management for biodiversity conservation and ecosystem services provision. However, the regeneration and succession of urban vegetation are rarely studied due to the complex settings of the urban environment. To this end, we conducted a large-scale field investigation in the metropolitan area of Beijing, China to explore the spatial variations in plant species composition and diversity in soil seed banks, and their similarity to the aboveground vegetation to assess the potential of urban plant regeneration. Overall, 657 vegetation and soil sampling plots from 219 grids, measuring 2 km × 2 km each, were investigated within two perpendicular 10 km wide transects running across the urban center in north-south and east-west directions within the 6th Ring Road of the city. We recorded a total of 102 plant species in soil seed banks, including 13 tree species, 10 shrub species, and 79 herb species. We found that the soil seed bank species diversity and its similarity to that of the aboveground vegetation communities decreased significantly with the urbanization intensity. Higher urbanization intensity is typically associated with increased human management and a reduction in Greenspace Area (GSA). Soil seed bank species richness increased significantly when GSA exceeded 45 % and the similarity of species composition and diversity between soil seed banks and aboveground vegetation communities was the highest in forest parks. This suggests that habitats under forest park management are more conducive to plant regeneration. Soil seed bank species diversity first increased and then decreased significantly with increased distance to the city center, whereas the species similarity between the soil seed banks and the aboveground vegetation communities showed little change with the ring roads going out. The results of this study have important implications for further understanding the potential for urban vegetation regeneration and sustainability, which have significant implications for urban biodiversity conservation and restoration. • Urbanization reduces the regeneration potential of vegetation communities. • Reduced management disturbances enhance plant biodiversity and seed dispersal. • Large greenspace and forest park are more suitable for vegetation regeneration. [ABSTRACT FROM AUTHOR]

Activities in urban parks contribute to greater socialization and a more active lifestyle, yet such health benefits could be mingled with health concerns – e.g., extreme thermal events or hazardous air quality, which received much less attention than the benefits. Particularly, there is a lack of empirical studies on behavioral changes under different thermal and air-quality conditions. To address the research gap, this study quantitatively measured the impact of thermal environmental parameters (air temperature, humidity, wind scale) and air quality parameters (PM 2.5 , PM 10 , NO 2 , SO 2 , O 3 , integrated air quality index (AQI)) on the daily attendance at Haidian Park – a neighborhood park – and Chaoyang Park – an urban recreational park – in Beijing covering consecutive days from April 1, 2020 to March 31, 2021. The analysis revealed the degrees to which urban park visits were influenced by temperature and air quality. Temperature had the greatest impact on the attendance, while the impact was asymmetric: The effect of low temperature showed more elasticity than that of high temperature. The influence of air quality was not as significant as that of the air temperature. The analysis also showed that such impacts of thermal and air-quality conditions on park visits were mediated by type of activities (the everyday-recreational continuum), days (weekday/weekend), and seasons. The findings provide useful implications for tackling the wicked problem of promoting outdoor activities in parks while controlling adverse effects of thermal and air-quality conditions. [ABSTRACT FROM AUTHOR]

Coal-fired combustion is recognized as a significant anthropogenic source of atmospheric compounds in Beijing, causing heavy air pollution events and associated deterioration in visibility. Obtaining an accurate understanding of the temporal trends and spatial variation characteristics of emissions from coal-fired industrial combustion is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, an integrated emission inventory of primary air pollutants emitted from coal-fired industrial boilers in Beijing is developed for the period of 2007–2013 using a technology-based approach. Future emission trends are projected through 2030 based on current energy-related and emission control policies. Our analysis shows that there is a general downward trend in primary air pollutants emissions because of the implementation of stricter local emission standards and the promotion by the Beijing municipal government of converting from coal-fired industrial boilers to gas-fired boilers. However, the ratio of coal consumed by industrial boilers to total coal consumption has been increasing, raising concerns about the further improvement of air quality in Beijing. Our estimates indicate that the total emissions of PM 10 , PM 2.5 , SO 2 , NO x , CO and VOCs from coal-fired industrial boilers in Beijing in 2013 are approximately 19,242 t, 13,345 t, 26,615 t, 22,965 t, 63,779 t and 1406 t, respectively. Under the current environmental policies and relevant energy savings and emission control plans, it may be possible to reduce NO x and other air pollutant emissions by 94% and 90% by 2030, respectively, if advanced flue gas purification technologies are implemented and coal is replaced with natural gas in the majority of existing boilers. [ABSTRACT FROM AUTHOR]

Black carbon (BC) and PM 2.5 were studied for nine years from 2005 to 2013 in the Beijing urban area. The overall weekly average mass concentrations of BC and PM 2.5 were 4.3 and 66.8 μg/m³. PM 2.5 annual means of the nine years are around 2 times of the standard (GB3095-2012) in China, and are 5–7 times higher than the WHO standard. The Beijing Olympic Games in 2008 was a milestone to mitigate aerosol pollution. Temporal distribution of BC shows a distinct declining trend, and annual mean mass concentrations of PM 2.5 after 2008 were lower than those before 2008 but increased from 2011 to 2013. Wind rose plots show that high BC concentrations are usually associated with low wind speed of northeastern or southwestern winds, generally causing poor visibility. Governmental mitigation measures such as traffic restriction despite increased motor vehicle numbers and gasoline consumption and industry relocation with declining consumption of coal and coke were successful in reducing BC emissions. Annual mean of BC was reduced by 38% in 2013 compared to 2005. However, BC contamination in Beijing is still severe when compared to other urban areas around the world. [ABSTRACT FROM AUTHOR]

Air pollution is a major trigger of chronic obstructive pulmonary disease (COPD). Dysregulation of the neuroendocrine hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal medullary (SAM) axes is essential in progression of COPD. However, it is not clear whether air pollution exposure is associated with neuroendocrine responses in individuals with and without COPD. Based on a panel study of 51 stable COPD patients and 78 non-COPD participants with 384 clinical visits, we measured the morning serum levels of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), cortisol, norepinephrine, and epinephrine as indicators of stress hormones released from the HPA and SAM axes. Ambient nitrogen dioxide (NO 2), fine particulate matter (PM 2.5), and meteorological conditions were continuously monitored at the station from 2 weeks before the start of clinical visits. Linear mixed-effects models were used to estimate associations between differences in stress hormones following an average of 1–14-day exposures to NO 2 and PM 2.5. The average 1 day air pollutant levels prior to the clinical visits were 24.4 ± 14.0 ppb for NO 2 and 55.6 ± 41.5 μg/m3 for PM 2.5. We observed significant increases in CRH, ACTH, and norepinephrine, and decreases in cortisol and epinephrine with interquartile range increase in the average NO 2 and PM 2.5 concentrations in all participants. In the stratified analyses, we identified significant between-group difference in epinephrine following NO 2 exposure in individuals with and without COPD. These results may suggest the susceptibility of COPD patients to the neuroendocrine responses associated with short-term air pollution exposure. [Display omitted] • Short-term NO 2 and PM 2.5 exposures are associated with stress hormones levels. • We compare pollutant-associated stress hormone responses in individuals with and without COPD. • Pollutant-associated neuroendocrine responses differ between individuals with and without COPD. [ABSTRACT FROM AUTHOR]

Urban green spaces (UGSs) are often positively associated with the health of urban residents. However, UGSs may also have adverse health effects by releasing biogenic volatile organic compounds (BVOCs) and increasing the ambient concentrations of ozone (O 3) and secondary organic aerosols in urban areas. BVOC emissions from UGSs might be underestimated because of the lack of consideration of the UGS land-use type in urban areas. As such, in this study, we used a newly released satellite dataset, Sentinel-2, with a resolution of 10 m, to derive the classification distribution of UGSs and predict the UGS emissions of BVOCs in Beijing in 2019. The results showed that the annual emissions of BVOCs from UGSs were approximately 2.9 Gg C (95% confidence interval (CI): 2.4–3.3) in the six core districts, accounting for approximately 39% of the total UGS emissions in Beijing. Compared with the results based on Sentinel-2, the BVOC emissions might be underestimated by approximately 37% (95% CI: 11–63) using the commonly used satellite dataset. UGSs produced the highest BVOC emissions in summer (from June to August), accounting for 75.2% of the annual emissions. UGSs contributed the most to the O 3 formation potential in summer, accounting for 41.5% of the total. We could attribute a considerable amount of the O 3 concentration (27.0 μg m−3, 95% CI: 21.4–32.6) to the UGS BVOCs produced in the core districts of Beijing in July. The new BVOC emissions dataset based on Sentinel-2 vegetation information facilitates modeling studies on the formation of surface O 3 in urban areas and assessments of the impact of UGSs on public health. [Display omitted] • Urban biogenic volatile organic compounds (BVOCs) were underestimated in summer. • A new satellite dataset of urban green space (UGS) gives a better estimation of BVOCs. • UGS BVOCs emissions in the core districts of Beijing were estimated to be 2.9 Gg C yr−1. • Approximately 13% of ozone concentration in summer can be attributed to UGS BVOCs. [ABSTRACT FROM AUTHOR]

Understanding the spatial patterns of atmospheric pollutants in urban and suburban areas is important for evaluating their effects on regional air quality, climate, and human health. The analyses of pollutant monitoring data of the China National Environmental Monitoring Center revealed that the differences in the concentrations of ambient O 3 , PM 2.5 , NO 2 , SO 2 , and CO between urban and suburban areas rapidly decreased from 2014 to 2019 in Beijing. Considering the negligible urbanization and interannual meteorological changes during the study period, the results reveal a quick response of the urban-to-suburban difference (Δ Urban-Suburban) in the ambient pollutants concentrations to emission reduction measures implemented in China in 2013. However, owing to the efficient O 3 formation in summer in urban areas in recent years, we observed a more rapid decrease in the Δ Urban-Suburban in O 3 concentration in summer (64.8%) than in winter (16.1%). In addition, the Δ Urban-Suburban in daytime summer O 3 changed from negative in 2014–2018 to positive in 2019, indicating that the daytime O 3 concentration in urban areas exceeded that in suburban areas. Furthermore, instantaneous changes in Δ Urban-Suburban in air pollutants were more sensitive to meteorological variations in 2014 than in 2019. The results indicate a less significant role of regional air mass transport in the spatial variability of pollutants under a future scenario of strong emission reduction in China. [Display omitted] • The Δ Urban-Suburban in the air pollutant concentrations rapidly decreased since 2014. •The daytime O 3 concentration in urban exceeded that in suburban area in 2019. •A quick response of the Δ Urban-Suburban to emission reduction measures is revealed. [ABSTRACT FROM AUTHOR]

In the context of urbanization, due to lack of the unified planning of land use for representative ecological indicators, the sustainable wildlife existence in urban ecosystems is emerging as a burning issue. A new descriptive method is proposed to establish the sustainable conservation strategy of protected wildlife in the current urbanization scenario. We use the Habitat Quality module in the Integrated Valuation of Ecosystem Services and Tradeoffs model (InVEST-HQ), straightforward construction package of complex ecological niche Ecological Niche Modeling at The MetaLand EcologyLab (ENMTML) and ecological corridors construction model Species Distribution Model toolbox (SDMtoolbox) to distinguish the priority protected areas (PAs) and construct the ecological corridors of Gallinula chloropus (G. chloropus) in Beijing-Tianjin-Hebei (BTH) region, China in 2018. The results show that the PAs are fragmented and only occupy 0.05% of total area in BTH region, which indicate an urgent conservation issue in highly urbanization area. For the sustainable conservation strategy of protected G. chloropus , 25 ecological corridors comprised 2790.8 km are required to construct, mainly distributed in Beijing and Tianjin city. Ecological corridors are also distributed close to the border of southeast, southwest and eastern coastal areas of the BTH region. In order to optimize the ecological corridors, 9 important ecological corridors comprised 813.4 km are suggested to build firstly, which are mainly distributed in the central and eastern coastal areas of the BTH region. Our combined modeling (ENMTML-InVEST-HQ) indicate that based on actual species occurrence data and land uses, it can successfully generate the PAs which should be paid more attention. Furthermore, concrete measures to build ecological corridors which connect PAs in BTH region are proposed. In order to well-targeted organized planning in highly urbanized areas, measures to protect key habitats of wildlife need to be defined and this research provides a reference for sustainable protection and management of wildlife. • The area of suitable habitats obtained by considering land use and type and human threat. • Combination of ENMTML package and InVEST-HQ model is proposed to determine the priority protected areas. • Ecological corridors are built to connect the fragmented priority protected areas. • Communication of species is promoted by the important ecological corridors. [ABSTRACT FROM AUTHOR]

• TAZ unit is applied to analyzing the relationships between urban features and LST. • SQR model explores heterogeneity of urban features on conditional low- or high-LST. • Spatial dependence bears a downward trend across the whole quantiles of LST. • SQR model is a promising method on estimation of LST. To seek mitigation strategies of urban heat island (UHI), many statistical methods have been applied to quantitatively explore the impact of driving factors on UHI. Nonetheless, the commonly used statistical models, such as ordinary least-squares (OLS) model and spatial autoregression model (SAM), were limited to explore the homogeneity relationship of driving factors on UHI. Although the spatial dependence of spatial data was considered, SAM failed to address the heterogeneity of relationships. In this study, a spatial quantile regression (SQR) model is innovatively introduced to investigate the relationships between driving factors and land surface temperature (LST) at different quantiles (heterogeneity) while considering spatial dependence. Substantial variations in SQR are found, compared with OLS and the spatial lag model (SLM). The coefficients of all driving factors in SQR are not constant and the spatial dependence shows an obvious downward trend throughout the whole quantiles of LST. The results of root mean square deviation (RMSD), coefficient of determination (R2) and concordance correlation coefficient (CCC) show that SQR has better performance than SLM in LST prediction. These indicate that the characteristics of both spatial dependence and heterogeneity are concurrence. Therefore, joint prevention strategies with regional governance according to local conditions are suggested to mitigate LST. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the dynamics of the microfauna community in activated sludge, with special reference to sludge bulking, in two parallel municipal wastewater treatment systems in Beijing, China over a period of 14 months. Annual cyclic changes in microfauna community structures occurred in both systems. RELATE analysis based on Spearman's Rank correlation indicated that microfauna community structures were highly correlated with the sludge volume index (SVI) (p <0.001), which indicates sludge settleability. Nutrient conditions of raw sewage (p <0.01) and hydraulic retention time (HRT) (p <0.05) were also related to microfauna community structures. Abundances of the species Epistylis plicatilis and Vorticella striata increased significantly with an increase in SVI (p <0.001) and decrease in water temperature (p <0.001), suggesting that sludge bulking may have created favorable conditions for the two species, even under unfavorable temperature conditions. Sludge de-flocculation primarily due to the excessive growth of Microthrix parvicella-like filaments could be an important driving force for the microfauna community changes. The release of flocculated non-filamentous bacteria may represent a suitable food source for these species. The two species may be considered as potential bioindicators for sludge bulking. [Copyright &y& Elsevier]

Lung cancer is the most common cancer in China and second worldwide, of which the incidence of lung adenocarcinoma is rising. As an independent factor, air pollution has drawn the attention of the public. An increasing body of studies has focused on the effect of PM 2.5 on lung adenocarcinoma; however, the mechanism remains unclear. We collected the PM 2.5 in two megacities, Beijing (BPM) and Shijiazhuang (SPM), located in the capital of China, and compared the different components and sources of PM 2.5 in the two cities. Vehicle emissions are the primary sources of BPM, whereas SPM is industrial emissions. We found that chronic exposure to PM 2.5 promotes the tumorigenesis and metastasis of lung adenocarcinoma in patient-derived xenograft (PDX) models, as well as the migration and invasion of lung adenocarcinoma cell lines. SPM has more severe effects in vivo and in vitro. The underlying mechanisms are related to the stem cell properties of cancer cells, the epithelial-mesenchymal transition (EMT) process, and the corresponding miRNAs. It is hopeful to provide a theoretical basis for improving air pollution in China, especially in the capital area, and is of the significance of long-term survival of lung cancer patients. [Display omitted] • PM 2.5 promote the metastasis of lung adenocarcinoma PDX models. • PM 2.5 from Shijiazhuang (SPM) has more severe effect than Beijing (BPM). • PM 2.5 promote the expression of CSCs-related genes of lung adenocarcinoma cell. • PM 2.5 regulated miRNA of CSCs-related pathway of lung adenocarcinoma cells. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between arterial stiffness and pre-diabetes when assessed by the new glycosylated hemoglobin A1c (HbA1c) 5.7%-6.4% criterion or by impaired fasting glucose in middle aged Chinese. Methods: 1122 adults aged 55 years or younger in the health examination centers for physical check-ups were enrolled in the two large-sized Tertiary Comprehensive Hospitals in Beijing from June 2011 to June 2012 after excluding those who previously had been diagnosed or treated as diabetes or cardiovascular disease. Subjects with a diagnosis of pre-diabetes according to impaired fasting glucose (IFG) (fasting plasma glucose (FPG) levels at 5.6-6.9 mmol/L), HbA1c levels at 5.7%-6.4%, or both, were classified into four groups for observation: (1) Normoglycaemia (HbA1c<5.7% and FPG <5.6 mmol/L); (2) IFG alone (FPG levels at 5.6-6.9 mmol/L and HbA1c<5.7%); (3) HbA1c 5.7%-6.4% alone (HbA1c levels at 5.7%-6.4% and FPG <5.6 mmol/L); and (4) both HbA1c 5.7%-6.4% and IFG (HbA1c levels at 5.7%-6.4% and FPG levels at 5.6-6.9 mmol/L). All subjects were measured for weight, height, waist circumference, blood pressure, fasting plasma glucose, HbA1c, lipid profile and brachial-ankle pulse wave velocity (baPWV). Results: The mean values of baPWV were 1282±8, 1311±10, 1398±30, and 1418±27 cm/s (Mean±SE) in Normoglycaemia, HbA1c 5.7%-6.4% alone, IFG alone and the both HbA1c 5.7%-6.4% and IFG groups, respectively. After adjusting for age, gender, blood pressure, BMI and triglyceride, baPWV was significantly higher in subjects with both HbA1c 5.7%-6.4% and IFG compared among the subjects with Normoglycaemia (1350±14 vs. 1301±6 cm/s, P=0.002) and HbA1c 5.7%-6.4% alone (1350±14 vs. 1309±8 cm/s, P=0.013). Conclusion: Subjects with pre-diabetes exhibited a greater arterial stiffness. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Symptomatic predictors of influenza could assess risks and improve decisions about isolation and outpatient treatment. To develop such predictors, we undertook a prospective analysis of pandemic (H1N1) 2009 and seasonal influenza (H3N2) in patients attending fever clinics. Methods: From 1 May 2009 to 1 January 2010, all adult patients admitted to fever clinics for suspected influenza, confirmed by real time RT-PCR, were enrolled. Predictors of influenza virus infection were selected with logistic regression models. Measures of sensitivity, specificity, positive and negative likelihood ratios (LRs) were calculated to identify the best predictors. Results: The clinical features and routine blood test results of influenza (H1N1) 2009 and seasonal influenza were similar. The positive and negative LRs of current US CDC influenza-like illness (ILI) criteria were modest in predicting influenza infection. Our modified clinic predictors improved the ability of the positive and negative LRs to recognize pandemic (H1N1) 2009 and seasonal influenza. The revised criteria are: fever ⩾38 °C accompanied by at least one of the following-cough, arthralgia or relative lymphopenia. Conclusion: Patients with symptoms and signs that meet the new criteria are likely to have influenza and timely antiviral therapy may be appropriate. In addition, physicians should ascertain if influenza is circulating within the community or if there is a contact history of influenza and combine this information with the newly developed criteria to clinically diagnose influenza. [Copyright &y& Elsevier]

Bulk deposition samples were collected in remote, rural village and urban areas of Beijing–Tianjin region, North China in spring, summer, fall and winter from 2007 to 2008. The annually averaged PAHs concentration and deposition flux were 11.81 ± 4.61 μg/g and 5.2 ± 3.89 μg/m2/day respectively. PHE and FLA had the highest deposition flux, accounting for 35.3% and 20.7% of total deposition flux, respectively. More exposure risk from deposition existed in the fall for the local inhabitants. In addition, the PAHs deposition flux in rural villages (3.91 μg/m2/day) and urban areas (8.28 μg/m2/day) was 3.8 and 9.1 times higher than in background area (0.82 μg/m2/day), respectively. This spatial variation of deposition fluxes of PAHs was related to the PAHs emission sources, local population density and air concentration of PAHs, and the PAHs emission sources alone can explain 36%, 49%, 21% and 30% of the spatial variation in spring, summer, fall and winter, respectively. [Copyright &y& Elsevier]

The concentrations, profiles, sources and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) were determined in 40 surface soil samples collected from Beijing, Tianjin and surrounding areas, North China in 2007, and all sampling sites were far from industrial areas, roadsides and other pollution sources, and across a range of soil types in remote, rural villages and urban areas. The total concentrations of 16 PAHs ranged from 31.6 to 1475.0 ng/g, with an arithmetic average of 336.4 ng/g. The highest PAH concentrations were measured in urban soils, followed by rural village soils and soils from remote locations. The remote–rural village–urban PAH concentration gradient was related to population density, gross domestic product (GDP), long-range atmospheric transport and different types of land use. In addition, the PAH concentration was well correlated with the total organic carbon (TOC) concentration of the soil. The PAH profile suggested that coal combustion and biomass burning were primary PAH sources. [Copyright &y& Elsevier]

Previous studies have reported inverse associations between urban greenness and mortality. However, findings regarding contemporaneous and cumulative average greenness exposure are inconsistent. A potential explanation is the weak effects of greenness among the general population. This study assessed the associations between contemporaneous and cumulative average greenness exposure and survival in lung cancer patients. An open cohort consisting of lung cancer patients enrolled from 1 January 2001 was studied. The cohort was followed up until 31 December 2018. We evaluated contemporaneous and cumulative greenness exposure using the normalized difference vegetation index (NDVI) within a 250 m buffer of each patient's geocoded residential address. The association between NDVI and mortality was evaluated using both time-fixed and time-varying Cox models. Their difference was compared either. In time-fixed Cox models, a 0.1-unit increment in contemporaneous and cumulative average NDVI was associated with 17% (95% confidence interval [CI], 15–18%) and 7% (95% CI, 5–8%) reductions in mortality rate, respectively. Time-varying Cox models consistently revealed significant associations, but their magnitudes were lower, at 2% (95% CI, 1–3%) for both contemporaneous and cumulative average NDVI. Compared to the time-fixed models, the time-varying ones exhibited better fit for the proportional hazard assumption in Cox regressions with more conservative results. Urban greenness is positively associated with an increased chance of survival in lung cancer patients. Compared to time-fixed Cox models, the results of time-varying Cox models were more conservative. This study confirms the beneficial health effects of urban greenness, which may facilitate the improvement of public health by urban green space planning. • Associations between urban greenness and mortality remain inconclusive. • We conducted a registry-based cohort study among lung cancer patients in Beijing. • Urban greenness is found positively associated with an increased survival rate. • The comparison shows time-varying model is more conservative to study greenness. [ABSTRACT FROM AUTHOR]

The article discusses the online branding of Beijing, China, by the government through the 2008 Olympics. It mentions how people construct the brand of Beijing by relying on the information provided in the Internet. It also explores the role of Web 2.0 in changing the pattern of branding communication by discussing how it empowers the public vis-à-vis official actors and how the public changes the Beijing brand through 'produsage.' It argues that, because of engagement with the people's construction, the official branding was unable to promote Green Beijing, High-tech Beijing and People's Beijing, which are the three core concepts of the Beijing brand.

Objective To describe the case fatality rate of SARS in Beijing. Methods Data of SARS cases notified from Beijing Center for Disease Control and Prevention (BCDC) and supplemented by other channels were collected. The data were analyzed by rate calculation. Results The case fatality rate of SARS in Beijing was 7.66%, and had an ascending trend while the age of cases was getting older, and a descending trend while the epidemic development. The case fatality rate in Beijing was lower than that in other main epidemic countries or regions. Conclusions The risk of death increases with the increment of age of SARS patients. Beijing is successful in controlling and treating SARS. [ABSTRACT FROM AUTHOR]

Objectives To assess the impacts of public health interventions on the outbreak of SARS in Beijing by analyzing the intervals between symptom onset, hospital admission and notification of its cases. Methods Data of SARS cases reported from the Beijing Municipal Centers for Disease Prevention and Control (BCDC) were collected and analyzed by descriptive epidemiology. Results in the early epidemic period, the intervals between the disease onset and the hospital admission seemed irregular, so was the intervals between the hospital admission and the notification. After the middle ten days of April, the intervals turned out to be more regular, and the disordered situation in terms of the hospital admission and the case notification was gradually brought under control. Conclusions Public health interventions against SARS has revealed positive impacts on SARS control program in Beijing. The timing and sensitivity of epidemic information reporting Systems has been greatly improved in Beijing as a result of successful fight against this disease. [ABSTRACT FROM AUTHOR]

Objective To describe the specific features of the contact history of probable cases of severe acute respiratory syndrome (SARS) in Beijing. Methods Data of SARS cases notified from the Beijing Municipal Center for Disease Control and Prevention (BCDC) and supplemented by other channels were collected. All the data were analyzed by descriptive epidemiology. Results 1) The number of probable cases with contact history was significantly higher than the excluded cases. 2) The proportion of probable cases with contact history descended with epidemic development, but this situation did not occur in health care workers (HCWs). 3) The fatality rate of probable cases with contact history was significantly higher than the cases without contact history (OR= 1.489). 4) The proportion of probable cases with contact history was 85.86% among health care workers, which was significantly higher than that of non-health care workers (85.86% v.s. 56.44%, OR=4.69). Conclusions 1) The susceptible persons with contact history may not get infected, and the contact history is just a sufficient condition of infecting SARS; 2) There are 3 conceivable reasons for the descending trend of the proportion in probable cases with contact history; 3) The contact history is one of the risk factors of the death of SARS cases; 4) The risk of contacting with SARS among health care workers is approximately 5 times higher than that of non-HCWs. [ABSTRACT FROM AUTHOR]

Research on the relationship between short-term exposure to fine particulate matter (PM 2.5) and urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) is sparse in the nonoccupationally exposed populations. A quasi-experimental observation of haze events nested within a randomized crossover trial of alternative 1-week real or sham indoor air filtration was conducted to evaluate the associations of urinary monohydroxy-PAHs (OH-PAHs) with short-term exposure to PM 2.5 and PM 2.5 -bound PAHs. The study was conducted among 57 healthy college students in Beijing, China. PM 2.5 -bound PAHs and urinary OH-PAHs were quantified using gas chromatography coupled with a triple-quadrupole tandem mass spectrometer. Linear mixed-effect models were applied to evaluate the association of urinary OH-PAHs with time-weighted personal PM 2.5 and PM 2.5 -bound PAHs, controlling for potentially confounding variables. The results demonstrated that air filtration could markedly reduce external exposure to PM 2.5 and PM 2.5 -bound parent, nitrated, and oxygenated PAHs. In the intervention trial, the urinary concentrations of 2-hydroxyfluorene (2-OH-FLU) and 9-hydroxyphenanthrene (9-OH-PHE) were elevated significantly by 16.5% (95% CI, 2.1%, 33.1%) and 37.9% (95% CI, 8.4%, 75.4%), respectively, in association with a doubling increase in personal PM 2.5 exposure. Urinary 9-OH-PHE was also significantly positively associated with the increase in the sum of PM 2.5 -bound parent PAHs. Furthermore, the levels of urinary OH-PAHs such as 2-OH-FLU and 9-OH-PHE in the haze events were elevated by 31.1% (95% CI, 8.7%, 53.4%) and 73.5% (95% CI, 16.0%, 131.0%), respectively, in association with a doubling increase in personal PM 2.5 exposure. The findings indicated that urinary 2-OH-FLU and 9-OH-PHE could serve as potential internal exposure biomarkers for assessing short-term PM 2.5 exposure in nonoccupational populations. [Display omitted] • Air filtration markedly reduced indoor PM 2.5 and most PM 2.5 -bound PAHs. • Air filtration abated increases in specific urinary OH-PAHs during haze events. • Urinary 2-OH-FLU and 9-OH-PHE could indicate short-term PM 2.5 exposure levels. Urinary 2-OH-FLU and 9-OH-PHE could serve as potential internal exposure biomarkers to indicate short-term PM 2.5 exposure in nonoccupational populations. [ABSTRACT FROM AUTHOR]

Ground-level ozone (O 3) has become the principal air pollutant in Beijing during recent summers. In this context, an investigation of ambient concentrations and variation characteristics of O 3 and its precursors in May and June from 2014 to 2017 in a typical urban area of Beijing was carried out, and the formation sensitivity and different causes of heavy O 3 pollution (HOP, daily maximum 8-h O 3 (MDA8h O 3)>124 ppbv) were analyzed. The results showed that the monthly assessment values of the O 3 concentrations (the 90th percentile MDA8h O 3 within one month) were highest in May or June from 2014 to 2017, and the values presented an overall increasing trend. During this period, the number of O 3 pollution days (MDA8h O 3 > 75 ppbv) also showed an increasing trend. During the HOP episodes, the concentrations of volatile organic compounds (VOCs), nitrogen oxides (NO X), and carbon monoxide (CO) were higher than their respective mean values in May and June, and the meteorological conditions were more conducive to atmospheric photochemical reactions. The HOP episodes were mainly caused by local photochemical formation. From 2014 to 2017, O 3 formation during the HOP episodes shifted from VOC and NO X mixed-limited to VOC-limited conditions, and O 3 formation was most sensitive to anthropogenic VOCs. Six categories of VOC sources were identified, among which vehicular exhaust contributed the most to anthropogenic VOCs. The VOC concentrations and OFPs of anthropogenic sources have decreased significantly in recent years, indicating that VOC control measures have been effective in Beijing. Nevertheless, NO X concentrations did not show an evident decreasing trend in the same period. Therefore, more attention should be devoted to O 3 pollution control in May and June; control measure adjustments are needed according to the changes in O 3 precursors, and coordinated control of VOCs and NO X should be strengthened in long-term planning. [Display omitted] • HOP episode occurrence frequency was the highest in May or June from 2014 to 2017. • HOP episodes were mainly caused by local photochemical formation. • VOCs, NO X , and CO concentrations increased during HOP episodes. • Vehicular exhaust contributed the most to anthropogenic VOCs. • Control strategy adjustment is needed according to the changes of precursors. [ABSTRACT FROM AUTHOR]

• We estimated multi-temporal anthropogenic heat flux (AHF) using a new framework. • The urban core has a low AHF but areas between 2nd and 4th ring-road have a high AHF. • AHF varies significantly among different seasons, with the highest AHF in winter. • AHF on workdays of january is higher than that on non-workdays from 7:00 to 20:00 h. • The detailed AHF patterns are helpful for solving urban thermal environment issues. Anthropogenic heat is a dominant component in the urban surface energy system and a key to understanding urban thermal environments. The top-down method was widely used to estimate anthropogenic heat flux (AHF) using statistical energy consumption data and proxies. However, there are several limitations. First, the coarse resolutions of current proxies cannot capture the heterogeneous AHF. Besides, the temporal resolution is generally low (annual) in most AHF studies using the top-down method. This study estimated AHFs from three sectors and their monthly and hourly patterns in Beijing, China by developing a new framework. We first used a new proxy of building volume to obtain the AHF from buildings. Then, we estimated the AHF from vehicles and human metabolism using road density and population density, respectively. Finally, the monthly and hourly (workday and non-workday) AHFs were derived using temporal downscaling methods. The results show that the historic buildings in the urban center have a relatively low AHF. Areas with high AHF mainly distribute in the region between the 2nd and 4th ring-road and industrial zones outside the 5th ring-road. The magnitude of AHF varies among months, with the maximum monthly AHF at the district level reaching 68.1 W/m2 in January. AHF in January workdays is significantly higher than that in January non-workdays during 7:00 h to 20:00 h. The estimated AHF in this study can better capture multi-temporal AHF through the top-down method and temporal downscaling methods. The improved AHF data help policymakers design various strategies to improve urban thermal environments under sustainable development goals. [Display omitted] [ABSTRACT FROM AUTHOR]

Following advancement in urbanization, outdoor thermal comfort is receiving increasing attention, with radiation being an influencing factor. To determine the shading preference, instead of a subjective questionnaire survey, an objective foot vote approach was proposed using remote sensing images. Subsequently, the meteorological data of cities were obtained from the Bureau of Meteorology. From the results, the foot vote was approximately consistent with the PMV, and pedestrians tended to move to the shaded area if it was hot and to the non-shaded area if it was cold. However, people do not move if the foot vote value ranges from 1 to 2, and the thermal acceptance range of PET is 19.2–29 °C in Beijing when using the definitions of foot vote. The outdoor thermal acceptance differs significantly with the types of outdoor sites and climates, and pedestrians in Beijing are significantly more sensitive than those in Wuhan if the outdoor thermal environment changes. Compared to transportation hubs and shopping malls, pedestrians in public buildings are less sensitive, whereas those in scenic spots are more sensitive. Results from this study will be beneficial to policymakers in urban designing to renovate and improve thermally comfortable urban environments at the pedestrian level. [Display omitted] • An objective foot vote approach from remote sensing images is proposed. • The foot vote approach is tested and consistent with PMV approach. • Air temperature and global radiation are important factors affecting foot votes. • Thermal acceptance range of PET is 19.2–29 °C in Beijing under foot vote approach. • Outdoor thermal sensitivity differs with the types of outdoor sites and climates. [ABSTRACT FROM AUTHOR]

• A bi-level optimization model is proposed for charging and discharging battery-exchange buses. • The calculation method of carbon quota for battery-exchange buses to participate in carbon trading market is put forward. • The battery-exchange buses participation in ancillary service market has economic benefits. The mode of battery replacement will become the main means of urban public transport energy supply, which will have a significant impact on the energy cost of public transport companies and the stability of the power system. Therefore, this paper proposes a charging and discharging optimization model for electric buses to participate in the carbon trading market and the peak shaving auxiliary service market. The upper model aims to minimize the total daily energy cost of the bus company, and the lower model is optimized based on the upper optimization results to minimize grid load fluctuations. Then, the scheme proposed in this paper is compared with disordered charging and orderly charging based on time of use price. Finally, a bus company in Beijing is taken as an example of simulation. The results show that compared with the disordered charging and the orderly charging based on time of use price, the charging and discharging schemes proposed in this paper can reduce the daily energy cost of 6052.68 yuan and 617.42 yuan respectively, reduce the fluctuation of power grid load by 92.14 % and 13.85 %, and reduce the carbon emission of the "bus power" combined system by 3930 kg and 2080 kg. [ABSTRACT FROM AUTHOR]

With the implementation of clean air strategies, PM 2.5 pollution abatement has been observed in the "2 + 26" cities in the Beijing-Tianjin-Hebei (BTH) region (referred to as the BTH2+26) and their surrounding areas. To identify the drivers for PM 2.5 concentration decreases in the BTH2+26 cites from the 2016/17 heating season (HS1617) to the 2017/18 heating season (HS1718), we investigated the contributions of meteorological conditions and emission-reduction measures by Community Multi-Scale Air Quality (CMAQ) model simulations. The source apportionments of five sector sources (i.e., agriculture, industry, power plants, traffic and residential), and regional sources (i.e., local, within-BTH: other cities within the BTH2+26 cities, outside-BTH, and boundary conditions (BCON)) to the PM 2.5 decreases in the BTH2+26 cities were estimated with the Integrated Source Apportionment Method (ISAM). Mean PM 2.5 concentrations in the BTH2+26 cities substantially decreased from 77.4 to 152.5 μg m−3 in HS1617 to 52.9–101.9 μg m−3 in HS1718, with the numbers of heavy haze (daily PM 2.5 ≥150 μg m−3) days decreasing from 17-77 to 5–30 days. The model simulation results indicated that the PM 2.5 concentration decreases in most of the BTH2+26 cities were attributed to emission reductions (0.4–55.0 μg m−3, 2.3–81.6% of total), but the favorable meteorological conditions also played important roles (1.9–25.4 μg m−3, 18.4–97.7%). Residential sources dominated the PM 2.5 reductions, leading to decreases in average PM 2.5 concentrations by more than 30 μg m−3 in severely polluted cities (i.e., Shijiazhuang, Baoding, Xingtai, and Beijing). Regional source analyses showed that both local and within-BTH sources were significant contributors to PM 2.5 concentrations for most cities. Emission controls in local and within-BTH sources in HS1718 decreased the average PM 2.5 concentrations by 0.1–47.2 μg m−3 and 0.3–22.1 μg m−3, respectively, relative to those in HS1617. Here we demonstrate that a combination of favorable meteorological conditions and anthropogenic emission reductions contributed to the improvement of air quality from HS1617 to HS1718 in the BTH2+26 cities. Image 1 1) PM 2.5 pollution abatements were witnessed by observations and simulations. 2) Both emission reductions and favorable meteorological conditions help to reduce PM 2.5 concentrations. 3) Residential sources dominated the PM 2.5 decreases in the Beijing-Tian-Hebei (BTH) region. 4) Local and within-BTH sources emission reduction controls contributed the most to PM 2.5 concentration decreases. [ABSTRACT FROM AUTHOR]

To explore high-resolution temporal variation characteristics of atmospheric metal elements concentration and more accurate pollution sources apportionment, online monitoring of metal elements in PM 2.5 with 1-h time resolution was conducted in Beijing from August 22, 2018 to August 21, 2019. Concentration of 18 elements varied between detection limit (ranging from 0.1 to 100 ng/m3) and nearly 25 μg/m3. Si, Fe, Ca, K and Al represented major elements and accounted for 93.47% of total concentration during the study period. Compared with previous studies, airborne metal pollution in Beijing has improved significantly which thanks to strict comprehensive control measures under the Clean Air Action Plan since 2013. Almost all elements present higher concentrations on weekdays than weekends, while concentrations of elements associated with dust sources during holidays are higher than those in working days after the morning peak, and there is almost no concentration difference in the evening peak period. Soil and dust, vehicle non-exhaust emissions, biomass, industrial processes and fuel combustion were apportioned as main sources of atmospheric metal pollution, accounting for 63.6%, 18.4%, 16.8%, 1.0% and 0.18%, respectively. Furthermore, main occurrence season of metal pollution is judged by characteristic radar chart of varied metal elements proposed for the first time in this study, for example, fuel combustion type pollution mainly occurs in winter and spring. Results of 72-h backward trajectory analysis of air masses showed that, except for local emissions, atmospheric metal pollution in Beijing is also affected by regional transport from Inner Mongolia, Hebei, the Bohai Sea and Heilongjiang. Image 1 • Content of 18 metals in PM 2.5 of Beijing with 1-h resolution for 1 year is gained. • Higher concentrations of metal elements are observed during weekdays than weekends. • K concentration in Beijing shows an order of winter > autumn > spring ≫ summer. • Soil and dust are identified as predominate source of metal elements in PM 2.5. • Radar chart of metal elements is used for the first time to discern pollution type. Temporal variations and source apportionment of metals are presented based on 1-h time resolution monitoring of metal elements in PM 2.5 in Beijing from August 22, 2018 to August 21, 2019. [ABSTRACT FROM AUTHOR]

Two plant-associated bacterial strains were isolated from Beijing, China. The two strains possessed almost identical 16S rRNA gene sequences. However, REP-PCR fingerprint patterns discriminated that they were not from one clonal origin. The average nucleotide identity (ANI) value and the digital DNA-DNA hybridization (dDDH) value between the two strains were 99.4% and 94.7%, respectively, suggesting that they belonged to the same species. The 16S rRNA gene phylogeny analysis indicated that the two strains belonged to the genus Variovorax and were closely related to V. paradoxus NBRC 15149T and V. boronicumulans BAM-48T. Their phylogenetic relationship were confirmed in both phylogenetic trees constructed with house-keeping gene sequences and concatenated core genes of the genome. The ANI and dDDH comparisons among 502T and the most related type strains showed values below the accepted threshold for species discrimination. The genome sizes of strains 502T and T529 were 6.76 and 6.69 Mbp, respectively. The strain 502T had 6,227 predicted genes with DNA G + C content of 67.4 %. The respiratory quinone was ubiquinone-8 and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphospatidylglycerol. The major fatty acids of strain 502T were C 10: 0 3-OH (26.2%), C 16:0 (12.9%), C 17:0 cyclo (14.5%) and summed feature 3 (21.4%). Furthermore, both strains showed the potential of plant growth promotion. Based on these results, the two isolates could be considered to represent a novel species of the genus Variovorax , for which the name Variovorax beijingensis sp. nov., is proposed, with 502T (= DSM 106862T = CGMCC 1.16560T) as the type strain. [ABSTRACT FROM AUTHOR]

Pollutant gases and particulate matters (PM) from livestock facilities can affect the health of animals and farm workers and lead to great social environmental risks. This paper presents a comprehensive study on the characteristics of ammonia (NH 3), nitrogen oxides (NO x), sulfur dioxide (SO 2) and PM (including PM 2.5 and PM 10) in a 100,000-bird manure-belt layer house in suburb Beijing for three typical seasons of summer, autumn and winter. Indoor air was sampled at an exhaust fan of the mechanically ventilated commercial house. The monitored indoor concentrations of NH 3 , NO x , SO 2 , PM 2.5 and PM 10 were 3.7–5.0 mg m−3, 17–58 μg m−3, 0–11 μg m−3, 100–149 μg m−3 and 354–828 μg m−3, respectively. The indoor NH 3 concentrations were largely influenced by the manure removal frequency. The NO x and SO 2 were mainly sourced from the ambient air, and the NO x was also partly sourced from manure decomposition in summer. The indoor PM 2.5 and PM 10 were largely sourced from the ambient air and the indoor manure, respectively. The abundant indoor NH 3 caused significantly higher NH 4 + concentration in the indoor PM 10 (7.98 ± 9.04 μg m−3) than that in the ambient PM 10 (3.48 ± 3.52 μg m−3). Secondary inorganic ions (SO 4 2−, NO 3 − and NH 4 +) totally contributed 5.7% and 14.6% to the indoor and ambient PM 2.5 , respectively; they contributed 2.8% and 8.9% to the indoor and ambient PM 10 , respectively. Organic carbon was the main component of the PM and accounted for 26.6% and 41.5% of the indoor PM 2.5 and PM 10 , respectively. Heavy metal elements (Zn, Cu and Cr) were likely transported from feed to manure and finally accumulated in the PM. Given the high emission potential, the air pollutants from animal production suggested potential risks for human health. Image 1 • Indoor NO x , SO 2 and PM 2.5 were mainly sourced from the ambient air. • Indoor NO x was also partly sourced from manure decomposition in summer. • Indoor PM 10 had higher NH 4 + concentration than ambient PM 10 (7.98 vs. 3.48 μg m−3). • Secondary inorganic ions contributed 5.7% (14.6%) to the indoor (ambient) PM 2.5. • Zn, Cu, Cr likely transported from feed to manure and finally accumulated in PM. Sources for aerial pollutants of NH3, NOx, SO2, PM2.5 and PM10 in layer house were identified. The characteristics of indoor PM components including heavy metal elements and secondary inorganic ions were revealed. [ABSTRACT FROM AUTHOR]

Purpose To explore the needs for basic community-based rehabilitation services for disabled persons in Xuanwu District, Beijing, China, and to identify factors which influence disabled persons to accept rehabilitation services. Method One hundred and eight disabled persons were selected by systematic sampling and simple random sampling to assess their needs for community-based rehabilitation services. Results Of the interviewees, 57.4% needed the community-based rehabilitation services, but only 13.9% took advantage of it. The main factors influencing the interviewees to accept these services were cost (P<0.05), knowledge about rehabilitation medicine (P<0.05); and the belief in the therapeutic benefit of the community-based rehabilitation service (P<0.05). Conclusion A considerable gap exists between the supply of community-based rehabilitation services in Beijing and the needs for these services by disabled residents underscoring the need for improved availability, and for additional research. [ABSTRACT FROM AUTHOR]

• The influence of adjacent room heat transfer on heating load is investigated. • Both measurement and simulation are adopted to validate the model accuracy. • Three factors are proved to have great impacts on adjacent room heat transfer. • Adjacent room heat transfer could takes up 40%–70% of the total heating load. • Quantitative study on adjacent room heat transfer promotes household heat metering. Household heat metering plays a significant role in building energy efficiency and has become an inevitable trend in northern China. Precise supplying aims to ensure indoor thermal comfort while realizing energy saving with occupants' behavior. Due to the different indoor temperature, interior envelope material and occupancy rate of each room, the Adjacent Room Heat Transfer (ARHT) will greatly affect the fair heating charging under household heating metering. This study takes an office building in Beijing as the object to measure the indoor and outdoor temperature in winter. EnergyPlus is adopted to establish a building model and calculate the heating load. The time-dependent temperature of the simulated room is compared with the hourly measured temperature to validate model accuracy. The validated model is further adopted to calculate the ratio of ARHT under three different conditions. The result indicates all these three factors have important impacts on ARHT. The ratio of ARHT to the real total heating load could stay around 40% and even reach up to 70%. The result shows an unexpected influence of ARHT, while it provides a case study for fair allocation of heat charges, which is vital to the implementation of household heat metering in China. [ABSTRACT FROM AUTHOR]

Understanding the level of indoor air quality is very important to improve the quality of air that people breathe indoors. In this paper, a comprehensive evaluation method combining rough sets and a wavelet neural network is proposed to evaluate the indoor air quality of buildings. Through on-site inspections of the indoor air in six large shopping malls in Beijing, Wuhan and Guangzhou, raw data of the environmental parameters affecting the indoor air quality of large shopping malls are obtained. First, rough sets are used to reduce the dimension of features that affect indoor air quality by removing unimportant features, and important environmental parameters that affect indoor air quality are obtained. These important environmental parameters are used as input parameters of the wavelet neural network. Then, the structure of the wavelet neural network is determined, and an evaluation model of the indoor air quality of buildings based on rough sets and the wavelet neural network is established. Finally, the model is applied to the evaluation of indoor air quality in large shopping malls, and the back propagation neural network, fuzzy neural network and Elman neural network are introduced for comparison of the testing accuracy of the wavelet neural network in the sample testing stage. The results show that the structure of the wavelet neural network is optimized by using a rough set to reduce the redundant attributes of the data, and that the comprehensive evaluation method based on rough sets and a wavelet neural network can accurately evaluate the indoor air quality level of buildings. The results of this study have significance for and can guide the evaluation of the indoor air quality of buildings. • A new comprehensive evaluation method is proposed for indoor air quality of buildings. • The combination of rough sets and a wavelet neural network is analyzed. • The genetic algorithm in RS theory is applied to perform attribute reduction. • The accuracy comparison of several evaluation models based on rough sets and different neural networks is made. [ABSTRACT FROM AUTHOR]

Particulate air pollution is a severe environmental problem in China, affecting visibility, air quality, climate and human health. However, previous studies focus mainly on large cities such as Beijing, Shanghai, and Guangzhou. In this study, an Aerodyne Aerosol Chemical Speciation Monitor was deployed in Baoji, a middle size inland city in northwest China from 26 February to 27 March 2014. The non-refractory submicron aerosol (NR-PM 1 ) was dominated by organics (55%), followed by sulfate (16%), nitrate (15%), ammonium (11%) and chloride (3%). A source apportionment of the organic aerosol (OA) was performed with the Sofi (Source Finder) interface of ME-2 (Multilinear Engine), and six main sources/factors were identified and classified as hydrocarbon-like OA (HOA), cooking OA (COA), biomass burning OA (BBOA), coal combustion OA (CCOA), less oxidized oxygenated OA (LO-OOA) and more oxidized oxygenated OA (MO-OOA), which contributed 20%, 14%, 13%, 9%, 23% and 21% of total OA, respectively. The contribution of secondary components shows increasing trends from clean days to polluted days, indicating the importance of secondary aerosol formation processes in driving particulate air pollution. The formation of LO-OOA and MO-OOA is mainly driven by photochemical reactions, but significantly influenced by aqueous-phase chemistry during periods of low atmospheric oxidative capacity. [ABSTRACT FROM AUTHOR]