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Water-soluble components have significant contribution to the oxidative potential (OP) of atmospheric fine particles, while our understanding of their relationship is still limited. In this study, the water-soluble OP levels in wintertime PM2.5 in the south and north of Beijing, representing the difference in sources, were measured with dithiothreitol (DTT) assay. The volume normalized DTT (DTTv) in the north (3.5 ± 1.2 nmol min-1 m-3) was comparable to that in the south (3.9 ± 0.9 nmol min-1 m-3), while the mass normalized DTT (DTTm) in the north (65.3 ± 27.6 pmol min-1 μg-3) was almost twice that in the south (36.1 ± 14.5 pmol min-1 μg-3). In both the south and north of Beijing, DTTv was better correlated with soluble elements instead of total elements. In the north, soluble elements (mainly Mn, Co, Ni, Zn, As, Cd and Pb) and water-soluble organic compounds, especially light-absorbing compounds (also known as brown carbon), had positive correlations with DTTv. However, in the south, the DTTv was mainly related to soluble As, Fe and Pb. The sources of DTTv were further resolved using the positive matrix factorization (PMF) model. Traffic-related emissions (39.1 %) and biomass burning (25.2 %) were the main sources of DTTv in the south, and traffic-related emissions (> 50 %) contributed the most of DTTv in the north. Our results indicate that vehicle emission was the important contributor to OP in Beijing ambient PM2.5 and suggest that more study is needed to understand the intrinsic relationship between OP and light absorbing organic compounds. [ABSTRACT FROM AUTHOR]

Ensemble forecasting systems have become an important tool for estimating the uncertainties in initial conditions and model formulations and they are receiving increased attention from various applications. The Regional Ensemble Prediction System (REPS), which has operated at the Beijing Meteorological Service (BMS) since 2017, allows for probabilistic forecasts. However, it still suffers from systematic deficiencies during the first couple of forecast hours. This paper presents an integrated probabilistic nowcasting ensemble prediction system (NEPS) that is constructed by applying a mixed dynamic-integrated method. It essentially combines the uncertainty information (i.e., ensemble variance) provided by the REPS with the nowcasting method provided by the rapid-refresh deterministic nowcasting prediction system (NPS) that has operated at the Beijing Meteorological Service (BMS) since 2019. The NEPS provides hourly updated analyses and probabilistic forecasts in the nowcasting and short range (0–6 h) with a spatial grid spacing of 500 m. It covers the three meteorological parameters: temperature, wind, and precipitation. The outcome of an evaluation experiment over the deterministic and probabilistic forecasts indicates that the NEPS outperforms the REPS and NPS in terms of surface weather variables. Analysis of two cases demonstrates the superior reliability of the NEPS and suggests that the NEPS gives more details about the spatial intensity and distribution of the meteorological parameters. [ABSTRACT FROM AUTHOR]

The implementation of air pollution reduction measures has significantly reduced the concentration of atmospheric fine particles (PM2.5) in Beijing, among which the "coal-to-gas" conversion measures may play a crucial role. However, the effect of this conversion measure on brown carbon (BrC) is not well known. Here, the chemical composition of BrC in humic-like fraction (HULIS-BrC) and water-insoluble fraction (WI-BrC) were characterized for ambient PM2.5 samples collected in Beijing before and after the "coal-to-gas" conversion measure. After the conversion measure, the number of HULIS-BrC compounds increased by ~14%, while the number of WI-BrC compounds decreased by ~8%. The intensity of over 90% of HULIS-BrC compounds also increased after the conversion measure, and correspondingly the O/C ratios of CHO and CHON compounds in HULIS-BrC fraction generally increased with the increase of intensity ratios after/before the conversion measure, indicating that there were more water-soluble highly oxygenated BrC compounds after "coal-to-gas" conversion measure. On the contrary, the intensity of more than 80% of WI-BrC compounds decreased after the conversion measure, and the O/C ratios of CHO and CHON compounds in WI-BrC fraction generally decreased with the decrease of intensity ratios after/before the conversion measure, indicating that after the "coal-to-gas" conversion measure the water-insoluble low oxygenated BrC compounds decreased. This work sheds light on the differences in the chemical composition of BrC between before and after the "coal-to-gas" conversion measure and suggests that future studies on the residential coal combustion BrC and secondary BrC deserve further exploration. [ABSTRACT FROM AUTHOR]

Backgroud: With the reform of medical system in China, Beijing municipal hospitals explored a new pharmaceutical care model and set up medication therapy management services (MTMs) in ambulatory care since 2019. We were one of the first hospitals to set up this service in China. At the present, there were relatively few reports about the effect of MTMs in China. In this study, we summarized the implementation of MTMs in our hospital, explore the feasibility of pharmacist-led MTMs in ambulatory care and the impact of MTMs on patients' medical costs. Methods: A retrospective study was conducted in a university-affiliated, tertiary comprehensive hospital in Beijing, China. The patients who received at least one MTMs and with complete medical records and pharmaceutical documents from May 2019 to February 2020 were included. Pharmacists provided pharmaceutical care for patients according to the MTMs standards issued by the American Pharmacists Association, identified the numbers and classification of the patients' perceived medication-related demands, identified medication-related problems (MRPs), and developed the medication-related action plans (MAPs). All MRPs found by pharmacists, pharmaceutical interventions, and resolving recommendations were documented, and calculate the cost of treatment drugs that patients can reduce. Results: A total of 112 patients received MTMs in ambulatory care, among them 81 cases with the completed record were included in this study. 67.9% of patients had five or more diseases, 83% of them co-took over 5 drugs. While performing MTMs, 128 patients' perceived medication-related demands were recorded in all, monitoring and judgment of adverse drug reaction (ADR) (17.19%) was the most common demand. 181 MRPs were found, with an average of 2.55 MPRs per patient. Nonadherence (38%), excessive drug treatment (20%), and adverse drug events (17.12%) were the top three MRPs. Pharmaceutical care (29.77%), adjustment of drug treatment plan (29.10%) and referral to the clinical department (23.41%) were the top three MAPs. Whereby the MTMs provided by pharmacists, the cost-saving of each patient was about $ 43.2 monthly. Conclusion: By participating in the MTMs of outpatients, the pharmacists could identify more MRPs and develop personalized MAPs timely for patients, thereby promoting rational drug use and reducing medical expenses. [ABSTRACT FROM AUTHOR]

Greenway is an important linear public space that meets the diverse needs of the public. With the increasing popularity of greenway construction, the study of different greenway usage behavior in different socio-economic areas is of great value to the detailed design and construction of greenway in the future. Using the theory of environment-behavior studies (EBS), this study selected representative urban greenways and suburban greenways in Beijing, China, and conducted a questionnaire survey. Descriptive statistics and the chi-squared test are used to quantitatively analyze and summarize the behavior of greenway users. It is found that user gender, educational level, and residence (i.e., permanent resident or visitor), as well as season of use, are highly similar for urban greenways and suburban greenways in Beijing. However, due to a close relationship with urban location, modified by temporal, spatial, and personal factors, different behavioral characteristics are evident as follows: (1) Urban greenways are most closely related to daily life, work and education of urban residents, with short travel distances, short single use time, high frequency of use, high social and cultural value, wide distribution of age groups and wide distribution of time periods of use. (2) Suburban greenways are an important choice for residents' outdoor activities on weekends and holidays. It is mainly used for ecological protection and sightseeing, supplemented by sports and fitness functions. It has the characteristics of low use frequency, high income level, wide distribution of time and distance, mainly used by young and middle-aged people, and used for a single time of more than 1 hour. Natural scenery along the trail is the most important attraction factor, and waterfront space and walking space are the main use behavior characteristics. [ABSTRACT FROM AUTHOR]

To mitigate haze pollution in China, a better understanding of the sources of carbonaceous aerosols is required due to the complexity in multiple emissions and atmospheric processes. Here we combined the analysis of radiocarbon and the stable isotope 13 C to investigate the sources and formation of carbonaceous aerosols collected in two Chinese megacities (Beijing and Xi'an) during severe haze events of a "red alarm" level from December 2016 to January 2017. The haze periods with daily PM 2.5 concentrations as high as ∼ 400 µ g m -3 were compared to subsequent clean periods (i.e., PM 2.5 less than median concentrations during the winter 2016/2017) with PM 2.5 concentrations below 100 µ g m -3 in Xi'an and below 20 µ g m -3 in Beijing. In Xi'an, liquid fossil fuel combustion was the dominant source of elemental carbon (EC; 44 %–57 %), followed by biomass burning (25 %–29 %) and coal combustion (17 %–29 %). In Beijing, coal combustion contributed 45 %–61 % of EC, and biomass burning (17 %–24 %) and liquid fossil fuel combustion (22 %–33 %) contributed less. Non-fossil sources contributed 51 %–56 % of organic carbon (OC) in Xi'an, and fossil sources contributed 63 %–69 % of OC in Beijing. Secondary OC (SOC) was largely contributed by non-fossil sources in Xi'an (56±6 %) and by fossil sources in Beijing (75±10 %), especially during haze periods. The fossil vs. non-fossil contributions to OC and EC did not change drastically during haze events in both Xi'an and Beijing. However, compared to clean periods, the contribution of coal combustion to EC during haze periods increased in Xi'an and decreased in Beijing. During clean periods, primary OC from biomass burning and fossil sources constituted ∼ 70 % of OC in Xi'an and ∼ 53 % of OC in Beijing. From clean to haze periods, the contribution of SOC to total OC increased in Xi'an but decreased in Beijing, suggesting that the contribution of secondary organic aerosol formation to increased OC during haze periods was more efficient in Xi'an than in Beijing. In Beijing, the high SOC fraction in total OC during clean periods was mainly due to an elevated contribution from non-fossil SOC. In Xi'an, a slight day–night difference was observed during the clean period with enhanced fossil contributions to OC and EC during the day. This day–night difference was negligible during severe haze periods, likely due to the enhanced accumulation of pollutants under stagnant weather conditions. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is the most common bacterium occurred in nosocomial infections and is also an important indicator of food spoilage. The worldwide spread of multidrug resistant (MDR) P. aeruginosa is threatening public health. However, the prevalence and spread of MDR P. aeruginosa through the food chain is little referred under the One Health perspective. Here, we collected a total of 259 animal-derived foods (168 chicken and 91 pork) from 16 supermarkets and farmer's markets in six regions of Beijing, China. The prevalence of P. aeruginosa in chicken and pork was 42.1 %. The phenotypic antimicrobial susceptibility testing showed that 69.7 % of isolates were MDR, and isolates from Chaoyang district exhibited a higher resistance rate compared to that from Xicheng district (p < 0.05). P. aeruginosa isolates exhibited high levels of resistance against β-lactams (91.7 %), cephalosporins (29.4 %), and carbapenems (22.9 %). Interestingly, none of strains showed resistance to amikacin. Whole-genome sequencing showed that all isolates carried various kinds of antimicrobial resistance genes (ARGs) and virulence genes (VGs), especially for bla OXA genes and phz genes. Multilocus sequence typing (MLST) analysis indicated that ST111 (12.8 %) was the most predominant ST. Notably, the emergence of ST697 clones in food-borne P. aeruginosa was firstly reported. In addition, the toxin pyocyanin was detected in 79.8 % of P. aeruginosa strains. These findings help to decipher the prevalence and the strong toxigenic ability of MDR P. aeruginosa from animal-derived foods and highlight the effective supervision of animal-derived food hygiene should be strengthened to prevent the spread of ARGs in a One Health strategy. • First comprehensive characterization of MDR P. aeruginosa isolates in animal-derived foods in Beijing, China. • High levels of resistance against β-lactams, cephalosporins, and carbapenems were found. • ST111 was the most predominant ST with high carriage rate of bla OXA-395. • The emergence of ST697 clones in food-borne P. aeruginosa was firstly reported. • High pyocyanin secretion rate was observed in P. aeruginosa isolates. [ABSTRACT FROM AUTHOR]

The thunderstorm gale recognition model is established by using support vector machine based on radar based data from the southern suburb observatory of Beijing and automatic stations. The specific algorithm is: firstly, 9 forecast factors are selected by analyzing 18 thunderstorms in Beijing area in 2010-2014 quantitatively using the statistical method, which are respectively the height of the echo top, the maximum albedo, the height of the maximum reflectivity, the vertical integral liquid water content, the time rate change of vertical integral liquid water content, the vertical integral liquid water content density, the height of the maximum reflectivity factor, the storm moving speed and the width of the velocity spectrum. 451 non high wind samples and 425 high wind samples are selected by matching the time and place of the automatic stations with the value of the quantitative index of the PUP storm monomer recognition product in all the cases. Secondly,the probability distribution of the prediction factors in the wind and non wind samples is calculated, and the degree of the corresponding forecast factors of the thunderstorm is obtained, then the sample data are normalized by the obtained membership function. Finally, the kernel function and model parameters are established, and the thunderstorm gale recognition model is established by using support vector machine. Two typical cases in Beijing Province are analyzed and tested, one caused by a line thunderstorm which happened on 7 July 2017, and the other caused by an isolated single-cell storm which happened on 19 May 2012.The results show that the identified wind range is consistent with the real one, and the hit rate, the false alarm rate and the critical success index are 92.0%,22.1%,73.0% and 99.1%,40.5%,59.2%,respectively. It will help to improve the accuracy of thunderstorm gale warning and forecasting. [ABSTRACT FROM AUTHOR]