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Aims: This study aimed to evaluate the association between gestational diabetes mellitus (GDM) and circulating folate metabolites, folic acid (FA) intake, and the methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) genotype. Materials and Methods: A prospective pregnancy cohort study was conducted in Beijing, China, from 2022 to 2023. Circulating folate metabolites, including red blood cell (RBC) 5‐methyltetrahydrofolate (5‐MTHF), 5, 10‐methylene‐tetrahydrofolate (5,10‐CH2‐THF), 5‐ formyltetrahydrofolate (5‐CHO‐THF), and unmetabolised folic acid (UMFA), and plasma homocysteine (HCY), 5‐MTHF, and methylmalonic acid (MMA), were determined at 6–17 weeks and 20–26 weeks of gestation. FA intake and the MTHFR and MTRR genotype were also examined. GDM was diagnosed between 24 and 28 weeks of pregnancy by a 75‐g oral glucose tolerance test (OGTT). The association between the folate status and GDM was ascertained using multivariate generalised linear models, logistic regression models, and restricted cubic spline regression, adjusting for potential confounders. Results: The study included 2032 pregnant women, of whom 392 (19.29%) developed GDM. UMFA above the 75th percentile (≥P75) [adjusted OR (aOR) (95% confidence interval [CI]) = 1.36 (1.01–1.84)], UMFA ≥ P90 [aOR (95% CI) = 1.82 (1.23–2.69)], and HCY ≥ P75 [aOR (95% CI) = 1.40 (1.04–1.88)] in early pregnancy, and RBC 5‐MTHF [aOR (95% CI) = 1.48 (1.10–2.00)], RBC 5,10‐CH2‐THF [aOR (95% CI) = 1.55 (1.15–2.10)], and plasma 5‐MTHF [aOR (95% CI) = 1.36 (1.00–1.86)] in mid‐pregnancy ≥ P75 are associated with GDM. Higher UMFA levels in early pregnancy show positive associations with the 1‐h and 2‐h glucose levels during the OGTT, and higher HCY levels are associated with increased fasting glucose levels during the OGTT. In comparison, RBC 5‐ MTHF and 5,10‐CH2‐THF, and plasma 5‐ MTHF in mid‐pregnancy are positively associated with the 1‐h glucose level (p < 0.05). The MTHFR and MTRR genotype and FA intake are not associated with GDM. Conclusions: Elevated levels of UMFA and HCY during early pregnancy, along with elevated RBC 5‐MTHF and 5,10‐CH2‐THF and plasma 5‐MTHF during mid‐pregnancy, are associated with GDM. These findings indicate distinct connections between different folate metabolites and the occurrence of GDM. [ABSTRACT FROM AUTHOR]

• Androgen receptor mutations were identified in women with Müllerian duct anomalies. • In silico analysis and ACMG guidelines classified the variants' pathogenicity. • Androgen receptor mutations resulted in conformational changes of the native protein. Müllerian duct anomalies (MDAs) are congenital developmental disorders exhibiting as a variety of malformations of female reproductive tract. The identified etiology of MDAs is limited. The present study aimed to unravel the underlying genetic causes of MDAs. Rare variants in androgen receptor (AR) were called from the cohort consists of patients with MDAs and underwent whole exome sequencing (WES) at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China. Sanger sequencing was used to confirm the causative genetic mutations. In silico analysis were used to classify the pathogenicity of each variant. Molecular modeling and simulations were conducted to investigate the conformational changes between the wild-type (WT) and mutant proteins. A total of 3 rare heterozygous variants in AR from the MDAs cohort in our institution were identified, with unknown effects. All variants were missense mutations, including c.173A > T, c.558C > A and c.1208C > T, and were absent or rare in East Asian populations in Genome Aggregation Database and the Exome Aggregation Consortium Database. According to the American College of Medical Genetics and Genomics guidelines, c.1208C > T variant was classified as likely pathogenic, while the other two were variants of uncertain significance. During molecular dynamics simulations, WT and mutant proteins all reached stable status according to root-mean-square variance. Values of radius of gyration showed that Q58L and S186R protein would be more compact than WT, while the structure of A403V became looser. Despite, in comparison with WT, the number of hydrogen bonds increased in Q58L, while decreased in the other two variants. Furthermore, the solvent-accessible surface area diminished in Q58L and A403V while enlarged in S186R proteins, when compared with WT. To our knowledge, this is the first report regarding the association of AR mutation and MDAs. The identification of these variants, predicted to damage the structure and function of AR protein, not only expanded the mutational spectrum of causative genes of MDAs, but provide novel molecular genetic reference for future studies. [ABSTRACT FROM AUTHOR]

Purpose: Older patients with cancer are underrepresented in pivotal trials of immune checkpoint inhibitors (ICIs). This study aimed to investigate immune-related adverse events (irAEs) that occur in older patients with lung cancer treated with ICIs, and explore predictors of the occurrence of irAEs. Methods: A prospective analysis was performed on older patients with lung cancer aged ≥ 65 years who were treated with anti-programmed cell death-1/-ligand 1 (PD-1/PD-L1) inhibitors in Beijing Hospital from January 2018 to December 2022. The incidence and risk factors of irAEs were estimated by the Chi-square test or Wilcoxon rank-sum tests. The predictive power of Geriatric-8 (G-8) for irAEs was tested by receiver operating characteristic (ROC) curve analysis. Lymphocyte counts were measured by flow cytometry. Cytokine levels were tested by Enzyme-linked immunosorbent assay, respectively. Kaplan–Meier method was used to calculated progression-free survival (PFS) curves, and the log-rank test was used to evaluate differences. Results: A total of 201 older patients aged ≥ 65 years with lung cancer were enrolled in this study. The most common irAEs were interstitial pneumonia, dermatological toxicity and hypothyroidism, with rates of 17.2%, 16.1% and 5.6%, respectively. ROC showed that G-8 could predict the occurrence of irAEs in patients aged 65–71 years (≥ G2 irAEs: AUC = 0.757, p < 0.001; ≥ G3 irAEs: AUC = 0.862, p < 0.001), but not for patients aged ≥ 71 years. NLR, LMR, PNI, hypertension and diabetes were associated with irAEs. Lower CD4 + T cells and B cells, and lower levels of IL-10 were associated with the development of irAEs. Conclusion: Our study confirmed the accuracy of G-8 for predicting irAEs in older patients. We also identified several predictors of irAEs in older patients with lung cancer. [ABSTRACT FROM AUTHOR]

Pelvic floor electrical stimulation (ES) is an effective treatment for pelvic floor dysfunction. However, the impact of ES on vaginal microbiota and local inflammatory response is yet poorly understood. Therefore, we designed a longitudinal study to investigate the impact of ES on vaginal microbiota and cytokines. A total of 170 participants were recruited into the study at Peking University International Hospital, Beijing, China, from December 2021 to April 2022. They were divided into two groups concerning the follow-up: long-term cohort (n = 147) following up to seven treatment sessions and short-term cohort (n = 23) following up to 7 h after a 30-min treatment. Paired vaginal discharge samples were collected from 134 individuals. Vaginal microbiota was characterized by 16S rRNA sequencing, and local cytokines concentrationswere detected by the cytometric bead arraymethod. A significant increase in the relative abundance of Lactobacillus spp. was observed after ES treatment (P < 0.001). In addition, L. crispatus (P = 0.012) and L. gasseri (P = 0.011) also increased significantly. Reduced microbial diversity was observed in the vaginal microbiota after the treatment. In the long-term cohort, a significant downregulation of IFN-g, IL-2, IL-4, IL-10, IL-17A, and TNF-awas compared with baseline. However, the short-term cohortpresentedwithanelevated IL-6 level at 7 h after the treatment. In conclusion, this study suggested that transvaginal electrical stimulationmight help to restore and maintain a healthy vaginalmicrobiota dominated by Lactobacillus, reducing the risk of vaginal inflammation. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization, road dust poses a significant threat to ecological systems. To explore the source and ecological risks associated with heavy metals in surface dust, 36 road dust samples were collected in Beijing in May, August, and November 2018, and February 2019. The results indicated that the concentrations of Cd, Cr, Cu, Hg, Ni, Pb, and Zn exceeded their background values, and the mean concentration of Cd was nearly 10 times the background value. Three main sources were identified by Principal Component Analysis (PCA): industrial emissions, fuel combustion, and traffic exhaust. According to the Genetic Algorithm optimized Back Propagation (GA-BP) neural network, heavy metals from industrial sources and fuel combustion originate from suburban districts, while heavy metals from traffic exhaust originate from the city center. After careful screening of species and corresponding toxicity data, the concentration of pollutants corresponding to a 5% cumulative probability on the curve (HC5) of eight heavy metals was calculated by species sensitivity distribution (SSD), and the results indicate that most HC5 values are consistent with national standards. However, the HC5 values of Ni, Cu, and As differed from the national standards, which can be used to supplement existing standards. From the risk analysis based on HC5 values, the high-risk area of Ni (12.70–30.97%) was much larger than that of As (1.55–4.95%), and the proportions of high-risk areas of Ni and As reached their highest values in spring and autumn, respectively. Uncertainty existed between different geostatistical methods. The areas of uncertainty of Ni and As were small (less than 5.58%). The heavy metals in the surface dust in Beijing had potential ecological risks that vary with seasons and regions. Therefore, it is critical to implement targeted management measures based on pollution sources and risk distribution. [ABSTRACT FROM AUTHOR]

• Renovation strategies prioritize the residential experience. • Identifies 20 patterns for designing public spaces, informing practical suggestions. • Examples are provided for renovating four courtyards and two hutongs. • Participation empowers residents to make renovation decisions autonomously. This paper proposes design strategies for renovating traditional communities in Beijing based on measured microclimate and thermal comfort and preserving historical authenticity to empower residents to make autonomous decisions about the renovation process. Based on the collected data from 11 hutongs and 102 courtyards in Dongcheng District, 4 representative courtyards and 2 representative hutongs are summarized. Microclimate data were collected in the representative months of January and September 2022. The design guidelines for 4 courtyards and 2 hutongs design guidelines, including 20 renovation modes, are proposed through on-site measurement and thermal comfort analysis. Due to the difference in microclimate, the proposed design guidelines can only be applied to the public space of traditional communities in Beijing but not to the public space in traditional villages in the suburbs. The application of the results also faces two challenges: the willingness of the public to participate in the renovation work and the demolition of illegal buildings. This study emphasizes human comfort as a factor to be considered in renovation projects. This study provides a standardized method for public space renovation in historic districts through microclimate analysis and thermal comfort assessment. [ABSTRACT FROM AUTHOR]

The focus of this study is an intense heat episode that occurred on 9–13 July 2017 in Beijing, China, that resulted in severe impacts on natural and human variables, including record-setting daily electricity consumption levels. This event was observed and analyzed with a suite of local and mesoscale instruments, including a high-density automated weather station network, soil moisture sensors, and ground-based vertical instruments (e.g., a wind profiler, a ceilometer, and three radiometers) situated in and around the city, as well as electric power consumption data and analysis data from the U.S. National Centers for Environmental Prediction. The results show that the heat wave originated from dry adiabatic warming induced by the dynamic downslope and synoptic subsidence. The conditions were aggravated by the increased air humidity during subsequent days, which resulted in historically high records of the heat index (i.e., an index representing the apparent temperature that incorporates both air temperature and moisture). The increased thermal energy and decreased boundary layer height resulted in a highly energized urban boundary layer. The differences between urban and rural thermal conditions throughout almost the entire boundary layer were enhanced during the heat wave, and the canopy-layer urban heat island intensity (UHII) reached up to 8°C at a central urban station at 2300 local standard time 10 July. A double-peak pattern in the diurnal cycle of UHIIs occurred during the heat wave and differed from the single-peak pattern of the decadal average UHII cycles. Different spatial distributions of UHII values occurred during the day and night. [ABSTRACT FROM AUTHOR]

HIV-1 dual infection occurs when an individual is simultaneously or sequentially infected with two or more genetically distinct HIV-1 strains. According to the number of infected strains, HIV-1 dual infection can be divided in double infection and triple infection and so on. Currently, the majority of dual infection cases have been reported to be double infections which can result in detrimental clinical outcomes. The high incidence of double infection among specific high-risk populations increases the likelihood of triple infection, which has been sporadically described. There is no doubt that we are concerned about the association between triple infection and disease progression. However, this relationship is still unclear on the population level. In this study, 70 individuals from the Beijing PRIMO cohort were longitudinally followed up with a median time of 15.75 months for the purpose of investigating the incidence of dual infection. Phylogenetic analyses using bulk and single-genome sequences showed that nine individuals acquired double infection, with the incidence of 9.21 per 100 person-years, and three individuals with triple infection were identified, with the incidence of 3.07 per 100 person-years. The further survival analysis demonstrated that the triple infection group exhibited faster CD4+ T-cell decline. In summary, these results demonstrate for the first time that the triple HIV-1 infection might reduce CD4+ T-cell counts, which would predict a more rapid disease progression. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine if there are any genetic changes with whole-exome sequencing associated with distal vaginal atresia. This was a retrospective genetics study of 5 patients who presented with distal vaginal atresia who were recruited between 2017 and 2018. Whole-exome sequencing was performed in each subject with distal vaginal atresia. Sanger sequencing was used to confirm the potential causative genetic mutation. Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China. The main outcome measure was the rare mutations potentially associated with distal vaginal atresia in 5 patients. A truncating mutation c.266delC (p.P89Rfs*5) in the T-box transcription factor 6 (TBX6) gene, which is highly expressed in the human vagina, was identified in 1 patient using whole-exome sequencing. The deletion of the 16p11.2 region containing the TBX6 locus has also been reported previously to have the clinical feature of Müllerian agenesis. This mutation was paternally inherited by the patient. This truncating mutation was absent from all of the databases we checked, suggesting that the variant is rare and pathogenic. We showed, to our knowledge, for the first time, that the mutation in TBX6 might be associated with human distal vaginal atresia. [ABSTRACT FROM AUTHOR]

Objectives: To determine whether a large-scale physical activity intervention could affect body composition in primary school students in Beijing, China. Methods: The study design was one-year cluster randomized controlled trial of physical activity intervention (20 min of daily exercise in the classroom) with an additional year of follow-up among 4 700 students aged 8-11 years at baseline. Results: After the one-year intervention, BMI increased by 0.56 kg/m2 (SD 1.15) in the intervention group and by 0.72 kg/m2 (SD 1.20) in the control group, with a mean difference of −0.15 kg/m2 (95% CI: −0.28 to −0.02). BMI z score decreased by −0.05 (SD 0.44) in the intervention group, but increased by 0.01 (SD 0.46) in the control group, with a mean difference of −0.07 (−0.13 to −0.01). After another year of follow up, compared to the control group, children in the intervention group had significantly lower BMI (−0.13, −0.25 to −0.01), BMI z score (−0.05, −0.10 to −0.01), fat mass (−0.27 kg, −0.53 to −0.02) and percent body fat (−0.53, −1.00 to −0.05). The intervention had a more pronounced effect on weight, height, BMI, BMI z score, and body composition among obese children than among normal weight or overweight children. Compared to the control group, the intervention group had a significantly higher percentage of children who maintained or reduced their BMI z score at year 1 (P=0.008) and year 2 (P=0.04). Conclusions: These findings suggest that 20 min of daily moderate to vigorous physical activity during the school year is a feasible and effective way to prevent excessive gain of body weight, BMI, and body fatness in primary school students. [ABSTRACT FROM AUTHOR]

The CALMET/CALPUFF modeling system was applied to estimate the air quality impacts of power plants in 2000 and 2008 in Beijing, and the intake fractions (IF) were calculated to see the public health risks posed. Results show that in 2000 the high emission contribution induced a relatively small contribution to average ambient concentration and a significant impact on the urban area (9. 52μg/m3 of SO2 and 5. 29μg/m3 of NOx). The IF of SO2, NOx and PM10 are 7. 4×10−6, 7. 4×10−6 and 8. 7×10−5, respectively. Control measures such as fuel substitution, flue gas desulfurization, dust control improvement and flue gas denitration planned before 2008 will greatly mitigate the SO2 and PM10 pollution, especially alleviating the pressure on the urban area to reach the National Ambient Air Quality Standard (NAAQS). NOx pollution will be mitigated with 34% decrease in concentration but further controls are still needed. [Copyright &y& Elsevier]

Based on the concentrations of ten heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe) in 144 road dust samples collected from 36 sites across 4 seasons from 2016 to 2017 in Beijing, this study systematically analyzed the levels and main sources of health risks in terms of their temporal and spatial variations. A combination of receptor models (positive matrix factorization and multilinear engine-2), human health risk assessment models, and Monte Carlo simulations were used to apportion the seasonal variation of the health risks associated with these heavy metals. While non-carcinogenic risks were generally acceptable, Cr and Ni induced cautionary carcinogenic risks (CR) to children (confidence levels was approximately 80% and 95%, respectively).. Additionally, fuel combustion posed cautionary CR to children in all seasons, while the level of CR from other sources varied, depending on the seasons. Heavy metal concentrations were the most influential variables for uncertainties, followed by ingestion rate and skin adherence factor. The values and spatial patterns of health risks were influenced by the spatial pattern of risks from each source. [Display omitted] • Temporal, spatial and source-specific variation in heavy metal health risks were explored. • Carcinogenic risk (CR) of Cr and Ni were cautionary to children in each season. • Health risks were from four main sources, fuel combustion was significant in all seasons. • Sources of CR changed with seasons, the use of pesticide and fertilizers peaked in spring. • Contributions and spatial patterns of CR were under combined effect of multiple sources. [ABSTRACT FROM AUTHOR]

Fourteen-month precipitation measurements from a second-generation PARSIVEL disdrometer deployed in Beijing, northern China, were analyzed to investigate the microphysical structure of raindrop size distribution and its implications on polarimetric radar applications. Rainfall types are classified and analyzed in the domain of median volume diameter D 0 and the normalized intercept parameter N w . The separation line between convective and stratiform rain is almost equivalent to rain rate at 8.6 mm h−1 and radar reflectivity at 36.8 dBZ. Convective rain in Beijing shows distinct seasonal variations in log 10 N w – D 0 domain. X-band dual-polarization variables are simulated using the T-matrix method to derive radar-based quantitative precipitation estimation (QPE) estimators, and rainfall products at hourly scale are evaluated for four radar QPE estimators using collocated but independent rain gauge observations. This study also combines the advantages of individual estimators based on the thresholds on polarimetric variables. Results show that the blended QPE estimator has better performance than others. The rainfall microphysical analysis presented in this study is expected to facilitate the development of a high-resolution X-band radar network for urban QPE applications. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive approach to renovating and optimizing balconies in old residential buildings in Beijing. Firstly, it explores residential balconies' evolution, characteristics, and development trends to identify various sample types and understand the associated problems and residents' needs related to balconies through investigation. Secondly, the Rhino/Grasshopper parametric platform is employed to simulate the performance and analyze data from standard balcony types, resulting in five qualitative and four quantitative renovation strategies and methods. Subsequently, these comprehensive renovation and optimization design strategies are implemented in the renovation process, and their performance is simulated. The daylight autonomy (DA), universal daylight indicator (UDI), and spatial daylight autonomy (sDA) metrics experienced significant increases of 16.56, 20.12, and 0.13, respectively, indicating improved light environment and functionality. Notably, the proposed strategies maintain consistent energy consumption and thermal comfort levels. Both PMV and PPD have improved, but the improvement is not significant, only by 0.01. The window-to-wall ratio has been increased by 0.1, and insulation has been added. The overall thermal comfort value is stable. These findings validate the practicality and effectiveness of the proposed approach and methods. This study provides valuable references for renovating and optimizing balconies in old residential buildings, contributing to problem-solving efforts and enhancing living quality. [ABSTRACT FROM AUTHOR]

In studying the spatial, temporal, and particle size variations heavy metal sources, a source apportionment model for a four-way array of data is required. In this study, referencing two-way and three-way models, a four-way (particle fractions, elements, sites, and time) source apportionment model (FEST) was developed. Errors in the three-way models solving four-way problems verified the necessity of developing the FEST model. The results showed that the FEST model had a higher accuracy than the existing models, which was probably because of more constraints and input data in the FEST model. Based on the sampled data in Beijing, sources were apportioned for the four-way array of data using the FEST model, and the spatial, temporal, and particle size variations of sources were evaluated. The main sources of heavy metals were similar to those in our prior studies, whereas the contributions of sources to specific heavy metals differed. Traffic exhaust and fuel combustion contributed more to fine particles than coarse particles, indicating that the two should be controlled preferentially among all sources. The management of traffic exhaust should be focused on the central and northern areas in each season, and the control of fuel combustion should be strengthened in the southern area in winter. [Display omitted] • A four-way source apportionment model (FEST) was developed for the first time. • Accuracy of the FEST model was higher than that of existing models. • Tempo–spatial and particle size changes of sources were analyzed using the FEST model. • Traffic exhaust and fuel combustion impacted larger on fine particles than coarse particles. [ABSTRACT FROM AUTHOR]

Abstract: The first Sino-German Symposium on DNA Repair and Human Diseases was held in the Capital Normal University, Beijing, China, from October 9th to 11th, 2010. It was initiated and organized by Xingzhi Xu and Zhao-Qi Wang with strong support from top scientists in the field from China, Germany and the United States. Financially, it was fully supported by the Sino-German Center for Science Promotion jointly founded by the National Natural Science Foundation of China (NSFC) and the Deutsche Forschungsgemeinschaft (DFG). This report summarizes 35 plenary lectures presented during this three-day symposium, with topics ranging from DNA damage checkpoint signaling, DNA repair, posttranslational protein modifications in DNA damage response (DDR) to DDR in ageing and cancer. This symposium stimulated extensive discussions on science and potential collaboration among the 230 participants. [Copyright &y& Elsevier]

Regional raindrop size distribution (DSD) features are poorly understood due to the lack of observations. Here we investigate the regional variability of summertime DSD in Beijing, using the DSD observations from ten disdrometer sites from April to September 2017. The characteristics of DSD are analyzed for both convective and stratiform precipitation, mainly classified by rain rate (R). The shape (μ) and slope (λ) parameters follow a second-degree polynomial regression relationship for both stratiform and convective precipitation. On average, stratiform precipitation is found to have larger values of μ and λ than convective precipitation, whereas convective precipitation has a larger mass-weighted mean diameter (D m) and a generalized intercept parameter (N w). Interestingly, the north of Beijing has larger values of μ and λ , as opposed to D m and N w that exhibit greater values in the south, which could probably be attributed to terrain differences. The rain rate dependence on DSD is analyzed as well. In general, the D m -R and N w -R relationships follow a power-law distribution, and both D m and N w increase significantly with R. As the rain rate increases, D m keeps increasing to around 1.5 mm until an equilibrium state is reached. The findings obtained here could provide useful reference for better estimations of rainfall using the remote sensing techniques. • Raindrop size distribution is reported from a network of disdrometers in Beijing. • Convective DSDs have larger D m and N w as compared to stratiform DSDs. • DSDs show variablity over space and dependence on precipitation regimes. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) and odors are two important gaseous pollutants escaped from landfill, which are harmful to human health and the surrounding environment. In this study, biofilter was used to control VOCs and odors from an actual landfill. The operating efficiency and mechanism of biofilters on the sealing zone and leachate treatment zone were respectively analyzed and compared. The results found that components of gaseous pollutants from these two zones are different. Hydrogen sulfide (572.96 μg/m3), ammonia (479.28 μg/m3), and dimethyl sulfide (279.81 μg/m3) were mainly detected in sealing zone, and dichloromethane (3573.97 μg/m3), triethylamine (1818.21 μg/m3), benzene (1809.11 μg/m3), and chlorobenzene (1286.81 μg/m3) were main components of gaseous pollutants in leachate treatment zone. Although the types and concentrations of gaseous pollutants in these two zones were significantly different, the biofilters showed good removal efficiencies. The average removal rate of the total VOC (TVOC), sulfides, and amines in both biofilters exceeded 80%. The outlet concentrations meet the level-3 standard of the Emission standards for odor pollutants (GB 14544–93). This is mainly related to the evolution of bacterial population during the operation of biofilters. In the inoculums, the dominant bacterial genus is Brevibacillus (58.84%), and bacteria with Bacillus and Pseudomonas only occupied 2.67% and 1.77%. With the extension of operation time, the dominant bacteria of biofilter in the sealing zone gradually evolved into Mycobacterium (67.82%) and Bacillus (27.90%), while the dominant bacteria of biofilter in the leachate treatment zone evolved into Bacillus (72.69%) and Pseudomonas (21.59%). These results indicated that identification of gaseous pollutant components and design of appropriate treatment systems based on their components will further improve the operating efficiency of biofilters in the actual landfill. Image 1 • Treatment of volatile organic compounds (VOCs) and odors by biofilters was studied. • Two biofilters were constructed in an actual landfill in Beijing. • Variation in waste gas concentrations and bacterial populations were analyzed. • The biofilters showed good removal efficiencies. • Scientific basis for co-treatment of VOCs and odors in landfills by biofilters provided. [ABSTRACT FROM AUTHOR]

Based on total lightning location data from the Beijing Lightning Network (BLNET) and hailfall reports from 2015 to 2017 in Beijing, as well as S-band radar data from the Beijing Meteorological Observation Center, the total lightning activities for 148 hailfall events are analyzed with the identification method of strong convective cells (CCs) (similar to Thunderstorm Identification Tracking Analysis and Nowcasting, TITAN). Most of the hailstorms have a very high flash rate (FR), and a significant increase in FR is observed before hailfall events. The 2σ lightning jump (LJ) algorithm (with 4 and 10 flashes/min activation thresholds for different districts of Beijing) is tested as a hailfall nowcasting predictor. The average LJ lead time is 27.1 min. LJs precede 81.8% of all hailfall events, and 38.6% of LJs are not followed by hailfall reports within one hour. The merging of two adjacent strong CCs usually forms hail-bearing severe thunderstorms producing a sudden increase in total lightning. In addition, most hailfall events occurred at the boundary of strong CCs instead of at the cell centers. This study shows that the total LJ is a potentially useful predictor for hail nowcasts in the Beijing area. • Detailed analysis on operational feasibility of the 2σ lightning jump algorithm for the hail nowcast in Beijing. • Hails usually occur in the vertical convection decline stage with the maximum VCS intensity exceeding 55 dBZ. • Hailstones are usually generated after two cells merge, except for isolated storms. [ABSTRACT FROM AUTHOR]