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Geological conditions of urban subway foundation pits are controllable factors in determining the deformation of pits. In this paper, the monitoring data and statistical data of a subway deep foundation pit in North China are presented and compared with those of Tianjin subway. The deformation characteristics of the proposed pit, open excavated with triple-layer steel supports, are introduced in detail. Based on the aforementioned information, the energy conservation equation of the mobilized strength design (MSD) method in which the compression deformation energy of internal support is considered is applied to predict the maximum lateral movement. The maximum lateral movement turns out to be 22.2 mm according to the improved MSD method, which is very close to the measured value. [ABSTRACT FROM AUTHOR]

Microplastic pollution is considered to be a major coastal environmental issue worldwide, and studies have confirmed the ubiquitous nature of microplastics on many beaches. To best of our knowledge, no previous study on microplastic pollution has been conducted in the present study area to date. This study examined the microplastic abundance, polymer type, size, shape and color in the sediments of Liuqinghewan Bathing Beach and the fishing port beach of Qingdao, China. Microplastics (1–0.5, 0.5–0.25 and 0.25–0.125 mm) were extracted from beach sediments using a density separation method. Fourier transform infrared (FTIR) spectroscopy was used to determine the chemical composition of the plastics while physical characteristics (size, shape, and color) of microplastics were observed using a stereomicroscope. The average microplastic abundance values with the grain size ranges from 1 to 0.125 mm at Liuqinghewan Bathing Beach and at the fishing port beach were approximately 208 ± 3.5 and 299 ± 5.7 microplastics per kg of dry sand, respectively. The number of microplastic particles with the grain size from 0.25 to 0.125 mm was significantly higher than for the other grain sizes. Microplastics were mainly multicolor fibers in all samples making up a large proportion that exceeded 97%. On the basis of FTIR analysis, the microplastics were shown to be composed of polypropylene and polystyrene at both sites. Microplastic characteristics used to identify their origin revealed high development and industrialization predict the non-point source of microplastics related to their hydrodynamic and geographical conditions. Assessing the distribution and characterization of microplastics on sandy beaches of some regions is not novel but a rather common study. However, the outcomes of current study furnish valuable and novel data for the evaluation of microplastic concentrations in beach sediments, environmental risks in China, and a baseline for future analysis. [ABSTRACT FROM AUTHOR]

Although much attention has been paid to investigating and controlling air pollution in China, the trends of air-pollutant concentrations on a national scale have remained unclear. Here, we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017, during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions. Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China, with an annual decrease of ∼7% compared with measurements in 2013. The measured decreased concentrations of SO2, NO2 and CO (a proxy for anthropogenic volatile organic compounds) could explain a large fraction of the decreased PM2.5 concentrations in different regions. As a consequence, the heavily polluted days decreased significantly in corresponding regions. Concentrations of organic aerosol, nitrate, sulfate, ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017, connecting the decreases in aerosol precursors with corresponding chemical components closely. However, surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017, which indicates stronger photochemical pollution. The boundary-layer height in capital cities of eastern China showed no significant trends over the Beijing–Tianjin–Hebei, Yangtze River Delta and Pearl River Delta regions from 2013 to 2017, which confirmed the reduction in anthropogenic emissions. Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017, although the ozone concentration has increased significantly, suggesting a more complex mechanism of improving Chinese air quality in the future. [ABSTRACT FROM AUTHOR]

Abstract: Regional composite pollution and variation of atmospheric oxidizing ability are significant problems in Beijing and its surrounding areas. In particular, a southwest–northeast prevailing wind makes nonlinear variation of ozone and its precursors complex. In this study, simultaneous measurements of surface ozone (O3), nitric oxide (NO), nitrogen dioxide (NO2), nitrogen oxide (NOx) and carbon monoxide (CO) were carried out from August 2009 to June 2010 to investigate ozone level and precursor concentrations in Northern China. Gucheng (GC), Longtanhu (LTH) and Xinglong (XL) were selected to represent rural area, urban area and background area in North China Plain, respectively. The results showed that there were two peaks for primary pollutants (NOx and CO) at urban and rural areas, and the highest values appeared nearly on rush hours. There was a single peak for O3 and Ox with peak values appearing at afternoon. The primary pollutants at urban and rural areas were higher than those in background region. However, the concentration of secondary pollutant O3 at downwind background areas was much higher than other sites due to transportation. Diurnal variations of pollutants indicated that O3 and Ox had peak values at afternoon, while other primary pollutants showed two peak values nearly on rush hours. Furthermore, high concentrations of O3 and Ox at background site XL also implied a robust atmospheric oxidizing ability. A positive correlation was observed between CO and O3 at XL site, which implied that air masses to the site had a large loading of anthropogenic emission experiencing strong photochemical processing. The correlation between CO and O3 was negative at GC and LTH, which indicated that local emission of precursors had significant influence on the formation of ozone. There was a positive correlation between NOx and Ox at GC and XL, which implied that NOx contributed to the formation of ozone, while a negative correlation meant titration in urban site LTH neutralized the formation of ozone due to high level of NO. [Copyright &y& Elsevier]

Abstract: Mud deposits are widespread in estuaries and on continental shelves, and contain important information regarding interactions between terrestrial and coastal processes. Magnetic properties of muddy sediments from the northeastern continental shelves of China, including shelves close to Korean coasts, were analyzed using bulk and size-fractionated samples to elucidate muddy sediment sources and transport. Types, concentration, and granulometry of magnetic minerals were determined and all samples were found to be dominated by magnetite. Muddy sediments from the Zhemin coast (off the Zhejiang and Fujian coasts) have the highest magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) values, while those from the central and southeastern South Yellow Sea and the western Korea Strait have lower values reflecting lower magnetic mineral concentrations. Single domain ferrimagnetic grains dominate the magnetic particles in the central South Yellow Sea, while superparamagnetic (SP) grains contribute significantly to the magnetic grains in the Bohai Sea. SP and coarse multi-domain (MD) grains dominate magnetic grain assemblages in the North Yellow Sea and along the Zhemin Coast. Rock sediment particle size is not a major factor affecting the magnetic properties of the mud deposits in the study area. Rather, terrigenous inputs and hydrodynamic transport processes primarily control the magnetic properties, and sediments from the Changjiang and Huanghe rivers make the most significant contribution. This observation applies to the whole study area, although terrigeneous magnetic mineral concentrations decrease with increasing distance from the river mouths due to both sorting and mixing with other sediments with weak magnetic signatures. Bacterial magnetosomes also play a role in the central South Yellow Sea. [Copyright &y& Elsevier]

Abstract: Provenance discrimination of marine sediments is an important topic in marine geology. Although the catchments of the Changjiang and Huanghe Rivers are regarded as the main sources of sediments on the shelves of the China Sea, identification of detailed sediment provenance is necessary for understanding sediment transport patterns and the paleoenvironment. Magnetic properties of both bulk sediment samples and different-sized particles from the Changjiang and Huanghe Estuaries are studied to discuss the origin of the sediments. The results show that the sediments are dominated by ferrimagnetic magnetite with a minor content of anti-ferromagnetic minerals such as hematite, and a higher concentration of ferrimagnetic minerals is observed for the Changjiang Estuary sediments. The crystal grains of ferrimagnetic minerals in the Changjiang Estuary are coarser than those in the Huanghe Estuary, whereas superparamagnetic grains significantly contribute to the Huanghe sediments. Magnetic parameters of χ SIRM, SOFT and χ ARM from different-sized particles present more obvious differences than these parameters from bulk particles, and S−100 and S−300 for both bulk samples and different-sized particles show distinct differences between the sediments from the two estuaries. Therefore the latter parameters are more useful to distinguish sediment origins. A comparison of the magnetic properties of sediments in these two estuaries with those on the shelves of the adjacent China Sea also suggests that the analysis of sediment magnetic properties is effective to identify sediment provenances. [Copyright &y& Elsevier]

Abstract: Bed features were mapped using a thermal depth recorder and a side-scan sonar in the Changjiang (Yangtze) Estuary, and flows were observed and bed surface materials were sampled to investigate bed material transport pathways. Distinct scales and dimensions of dunes were observed in terms of the classification scheme of Ashley [Ashley, G.M., 1990. Classification of large-scale sub-aqueous bedforms: A new look at an old problem. Journal of Sedimentary Research, 61, 160–172], forming a dune set in the flood season. Large dunes occurred predominately in the surveyed area of the estuarine zone, and two-dimensional dunes predominated in the dry season while three-dimensional dunes prevailed in the flood season. Sharp lee sides of dunes have low angles, indicating a significant suspended-load transport for the bedform migration, and the majority of them face down-estuary reflecting the controlling process by the ebb current. The bed material migrations in terms of relative maximum gross transport show a satisfactory agreement with the sonar mapping in the dry season. The relative maximum gross transport as an independent estimator of migration direction, can be used to effectively determine the bed material transport directions in the Changjiang Estuary. [Copyright &y& Elsevier]

Extraterrestrial particles have higher 3He/4He ratios than those of terrestrial sediments (> 100 Ra versus <0.03 Ra, where Ra is the 3He/4He ratio normalized to the atmospheric value of 1 .4×10-6). The inter-planetary dust particles (IDPs), which are very rich in 3He, continuously bombard the Earth and can accumulate in deposits. IDPs sedimentation rate changes can significantly influence 3He concentration in the Earth surface sediments. Since IDPs are not easy to detect in terrestrial deposits, measuring helium isotopes is a helpful approach to examine changes in IDPs. Helium concentration and helium isotopic composition magnetic substances and the quartz particles were examined for helium concentration and helium isotopic ratio. Results show that the 3He/4He ratio and the 3He concentrations of the magnetic substances are clearly higher than those of the bulk samples and the quartz particles, and, the 3He/4He ratio of the extracted magnetic substances is also higher than that of the average level of the Earth's crust. The higher helium content in the magnetic fractions can be explained by an influx of IDPs. [ABSTRACT FROM AUTHOR]

China is the largest producer and consumer of rice in the world and a pioneer in applying hybrid rice technology. Although hybrid rice has contributed greatly to Chinese agriculture in the past decades, its potential to improve grain quality further is being questioned. However, to meet the challenges posed by severe crop damage by pests and diseases, the extensive use of pesticides and chemical fertilizers, and a shortage of water and energy, more elite rice cultivars are needed. In recent years, China has seen continued improvements in rice genetics, powered by functional genomics as a way forward to safeguard its rice production. Here, we briefly review the current status of rice breeding in China through strategies integrating hybrid rice technology, molecular marker-assisted breeding, functional genomics and genetically modified rice. [Copyright &y& Elsevier]

Spartina alterniflora (S. alterniflora) has grown rapidly in China since its introduction in 1979, showing the trend of alien species invasion, which has seriously affected the ecosystem balance of coastal wetlands. The temporal and spatial expansion law of S. alterniflora can be obtained through remote sensing monitoring, which can provide a reference and basis for S. alterniflora management. This paper presents a method for extracting and mapping S. alterniflora based on phenological characteristics. The coastal areas of the Yangtze River Delta Urban Agglomeration are selected as the research area, and the Landsat time series data from 1990 to 2022 on the Google Earth Engine (GEE) platform are used to support the experiment in this paper. Firstly, the possible growing area of S. alterniflora was extracted using the normalized differential moisture index (NDMI), normalized differential vegetation index (NDVI), and normalized differential water index (NDWI); Then, the time series curve characterizing the phenological characteristics of vegetation was constructed using the vegetation index to determine the difference phase of phenological characteristics between S. alterniflora and other vegetation. Finally, a decision tree was constructed based on the phenological feature difference phase data to extract S. alterniflora, and it is applied to the analysis of temporal and spatial changes of S. alterniflora in the study area from 1990 to 2022. The results show that the area of S. alterniflora increased from ~1426 ha in 1990 to ~44,508 ha in 2022. However, the area of S. alterniflora began to show negative growth in 2015 due to the construction of nature reserves and ecological management. The results of correlation analysis showed that the growth of C. japonicum was significantly affected by temperature stress and weakly affected by precipitation. This study verified that Landsat time series images can effectively extract vegetation phenological information, which has strong feasibility for extraction and dynamic monitoring of S. alterniflora and provides technical support for the management and monitoring of invasive plants in coastal wetlands. [ABSTRACT FROM AUTHOR]

Background: The incidence and death rate of non-small cell lung cancer (NSCLC) in China ranks the first among the malignant tumors. Circular RNA (circRNA) was reported to be involved in the progression of NSCLC. Our study aimed to investigate the underlying mechanism of circ_0020123 in NSCLC progression. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circ_0020123, miR-590-5p and Thrombospondin 2 (THBS2) in NSCLC tissues and cells. Cell proliferation and migration were examined by Cell Counting Kit-8 (CCK-8) assay and Transwell assay, respectively. Flow cytometry assay was used to detect the apoptosis of NSCLC cells. The protein levels of Ki-67, matrix metalloprotein-9 (MMP-9), Cleaved-caspase9 (Cleaved-casp9) and THBS2 were detected by Western blot. The targets of circ_0020123 and miR-590-5p were predicted by starBase 3.0 and TargetScan, and then confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. The animal experiment showed the effect of circ_0020123 on tumor growth in vivo. Results: The expression of circ_0020123 was upregulated in NSCLC tissues and cells. Functionally, circ_0020123 downregulation inhibited the proliferation and migration and promoted the apoptosis of NSCLC cells. Interestingly, circ_0020123 directly targeted miR-590-5p, and inhibition of miR-590-5p reversed the knockdown effects of circ_0020123 on NSCLC cells. More importantly, THBS2 was a target of miR-590-5p, and THBS2 overexpression reversed the effects of circ_0020123 knockdown on cell proliferation, migration and apoptosis in NSCLC cells. Finally, suppression of circ_0020123 inhibited tumor growth in vivo through miR-590-5p/THBS2 axis. Conclusion: Circular RNA circ_0020123 regulated THBS2 by sponging miR-590-5p to promote cell proliferation and migration and inhibit cell apoptosis in NSCLC cells. [ABSTRACT FROM AUTHOR]

Having a high-quality historical air pollutant dataset is critical for environmental and epidemiological research. In this study, a novel deep learning model based on convolutional neural network architecture was developed to estimate ground-level ozone concentrations across eastern China. A high-resolution maximum daily average 8-h (MDA8) surface ground ozone concentration dataset was generated with the support of the total ozone column from the satellite Tropospheric Monitoring Instrument, meteorological data from the China Meteorological Administration Land Data Assimilation System, and simulations of the WRF-Chem model. The modeled results were compared with in situ measurements in five cities that were not involved in model training, and the mean R2 of predicted ozone with observed values was 0.9, indicating the good robustness of our model. In addition, we compared the model results with some widely used machine learning techniques (e.g., random forest) and recently published ozone datasets, showing that the accuracy of our model is higher and that the spatial distributions of predicted ozone are more coherent. This study provides an efficient and exact method to estimate ground-level ozone and offers a new perspective for modeling spatiotemporal air pollutants. [ABSTRACT FROM AUTHOR]

Background: This study analyzed factors that affect the financial burden and utilization of medical services of patients with diabetes in a city of China. Methods: We randomly sampled 10% of the information on the front page of diabetic inpatient medical records in the city from January 2014 to September 2019. Total cost of hospitalization, length of hospitalization and the number of hospitalization were analyzed. Descriptive statistical analysis and multiple linear regression analysis were adopted. Results: Understanding the current financial burden of diabetic patients and the use of medical services, the results show that the direct economic burden of diabetic patients per hospitalization was approximately 8,000 Yuan, and the indirect economic burden was approximately 2,000 Yuan. Age, medical payment methods, admission channels, and medical institution grades are all important factors affecting medical expenses and medical service utilization of diabetic patients. In addition, the inequality of medical service utilization of patients is increased due to different types of medical insurance. Conclusions: To reduce the economic burden on patients and society, governments should strengthen supervision, the advancement of diagnosis and treatment systems, the service conditions of primary medical institutions, the management of medical services, and the use of medical resources. To create a more impartial medical and health environment where the value of medical staff are truly reflected, financial investments should be attained to improve medical technologies and labor costs. [ABSTRACT FROM AUTHOR]

Abstract: Aim: We aimed to appraise the quality of Chinese Society of Infectious Diseases of China Medical Association clinical practice guidelines (CPGs) for infectious diseases in China. Methods: We performed the electronic search and hand search on the above‐mentioned CPGs for infectious diseases published from January 1997 to October 2017. Each publication was evaluated using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. Results: Thirteen guidelines were identified and enrolled for the further evaluation. The median scores of the AGREE II domains across all 13 guidelines were as follows: scope and purpose 73.61% (36.11% to 84.72%), stakeholder involvement 12.50% (8.33% to 20.83%), rigor of development 19.27% (12.50% to 26.04%), clarity of presentation 86.11% (23.61% to 94.44%), applicability 33.33% (26.04% to 50.00%), and editorial independence 8.33% (4.17% to 16.67%). The clarity of presentation domain got the highest score among the six domains. Moreover, when compared the CPGs by the year of publication (2002 to 2006 vs. 2007 to 2017), the quality scores were higher in the CPGs published in the last 10 years than those published before, but with no significant difference. Conclusions: The quality score of CPGs for infectious diseases in China from January 1997 to October 2017 was moderate, but had significant shortcomings, especially in the stakeholder involvement and editorial independence domains. However, the AGREE II instrument is useful and feasible for appraising the CPGs and should be applied to develop, implement, and promote the CPGs in China. [ABSTRACT FROM AUTHOR]

Climatic conditions, including temperature range and solar radiation, are closely linked to maize ( Zea mays L.) growth and development. Adjusting plant density is one of the most effective measures for maximizing maize yield under different climatic conditions. The objectives of this study were (1) to determine the optimum plant density as well as the corresponding leaf area index (LAI) and yield in different maize producing regions in China and (2) to learn how climatic conditions influence maize growth and grain yield. The 3-year (2013–2015) field experiment used a hybrid maize cultivar (‘Zhengdan 958’) with six plant density treatments: 4.5, 6, 7.5, 9, 10.5, and 12 plants m −2 . Three different ecological regions were chosen for the study: Gongzhuling (Jilin Province, China), Yinchuan (Ningxia Hui Autonomous Region, China), and Qitai (Xinjiang Uygur Autonomous Region, China). Comparing the same plant density treatment at different sites, grain yield and dry matter accumulation decreased in the order Qitai > Yinchuan > Gongzhuling. The optimum plant densities (i.e., treatments with greatest yield) were 12 plants m −2 at Qitai, 10.5 plants m −2 at Yinchuan, and 7.5 plants m −2 at Gongzhuling. At the optimum plant density, the LAIs at silking and physiological maturity were, respectively, 8.94 and 4.27 at Qitai, 7.50 and 1.85 at Yinchuan, and 6.18 and 1.67 at Gongzhuling. Climatic factors, especially solar radiation and diurnal temperature range, exerted significant influences on maize yield. These observations will be useful for determining best management practices for maize production under different climatic conditions across large areas and for providing helpful suggestions for maize breeders. [ABSTRACT FROM AUTHOR]

Accurate estimation of maize (Zea mays L.) straw production and exploration of appropriate straw return rate have important reference for guiding the comprehensive utilization of crop straw. In this study, we estimated the maize straw production (including aboveground straw and root straw) in recent ten years (2009–2018) of the four largest maize growing regions across China using the latest obtained region-specific maize straw index and root-shoot ratio and then determined the appropriate straw return rate of different regions based on the carbon (C) balance between straw C input and the total C emissions generated in maize cultivation. Our results showed that there were significant differences in maize straw index (MSI) and root-shoot ratio between different maize growing regions in China with spatial distribution trends of Huanghuaihai (HM) > North (NM) > Southwest (SW) > Northwest (NW) maize regions and SW > NW > NM > HM, respectively. On average, in the recent ten years, the total maize straw production of the four major regions was 216.03 Mt yr−1, including 192.73 Mt yr−1 for the aboveground straw production and 23.30 Mt yr−1 for root straw production. Nationally, when the maize straw return rate was 70.4% (45.8%, 57.4%, 62.2% and 84.5% in SW, HM, NW and NM respectively), the straw C input into soil can theoretically counterbalance the total C emission generated in maize cultivation. Additionally, the total soil organic C sequestration increased from 11.26 to 18.88 Mt C yr−1 for the whole four regions under the scenarios of 0%, 25%, 50%, 75% and 100% maize straw return. • The latest region-specific MSI and root-shoot ratio were obtained in China. • Maize straw productions of different maize growing regions in China were estimated. • Nationally, the optimal maize straw return rate was 70.4% to achieve carbon balance. • The total SCS was from 11.26 to 18.88 Mt C yr-1 under different maize straw return scenarios. [ABSTRACT FROM AUTHOR]

Abstract: Leprosy continues to be detected at near stable rates in China even with established control programs, necessitating new knowledge and alternative methods to interrupt transmission. A molecular epidemiology investigation of 190 patients was undertaken to define Mycobacterium leprae strain types and discern genetic relationships and clusters in endemic and non-endemic regions spanning seventeen provinces and two autonomous regions. The findings support multiple locus variable number of tandem repeat (VNTR) analysis as a useful tool in uncovering characteristic patterns across the multiethnic and divergent geographic landscape of China. Several scenarios of clustering of leprosy from township to provincial to regional levels were recognized, while recent occupational or remote migration showed geographical separation of certain strains. First, prior studies indicated that of the four major M. leprae subtypes defined by single nucleotide polymorphisms (SNPs), only type 3 was present in China, purportedly entering from Europe/West/Central Asia via the Silk Road. However, this study revealed VNTR linked strains that are of type 1 in Guangdong, Fujian and Guangxi in southern China. Second, a subset of VNTR distinguishable strains of type 3, co-exist in these provinces. Third, type 3 strains with rpoT VNTR allele of 4, detected in Japan and Korea were discovered in Jiangsu and Anhui in the east and in western Sichuan bordering Tibet. Fourth, considering the overall genetic diversity, strains of endemic counties of Qiubei, Yunnan; Xing Yi, Guizhou; and across Sichuan in southwest were related. However, closer inspection showed distinct local strains and clusters. Altogether, these insights, primarily derived from VNTR typing, reveal multiple and overlooked paths for spread of leprosy into, within and out of China and invoke attention to historic maritime routes in the South and East China Sea. More importantly, new concepts and approaches for prospective case finding and tracking of leprosy from county to national level have been introduced. [Copyright &y& Elsevier]

Aerosol pollution is an acute environmental issue in developing countries. Asia has been experiencing rapid changes in anthropogenic aerosols during the past two decades due to fast growth in population and economy. It is still an open question how aerosol loadings, represented by aerosol optical depth (AOD), have evolved in this century, particularly during the past decade when China and India implemented a clean air act aiming to improve air quality. Based on Terra aerosol retrievals and aerosol reanalysis, a change point of AOD trend is detected at 2010 in East China versus a persistent increasing AOD trend in the Indian subcontinent with no detectable change point from 2000 to 2019. In East China, positive AOD trend (+0.11 ± 0.022 decade−1) is confirmed from 2000 to 2010 (hereinafter the former period) yet negative trend (−0.26 ± 0.027 decade−1) is identified from 2011 to 2019 (hereinafter the later period). In the Indian subcontinent, persistent positive trend (+0.04 ± 0.001) is detected from 2000 to 2019 (hereinafter the whole period). All of these trends are attributed mainly to changes in sulfate aerosols. Further analysis of the aerosol pollution extreme events (APEE; defined as daily AOD over the long-term local 90th AOD percentile) manifest a positive trend (+0.16 ± 0.029 decade−1) of the APEEs' magnitude in East China during the former period yet a negative trend (−0.11 ± 0.020 decade−1) during the latter period; the Indian subcontinent demonstrates a positive trend (+0.02 ± 0.004 decade−1) during the whole period due to increasing sulfate aerosols. The APEEs have become more frequent (+3.5 ± 0.53 day month−1 decade−1) in East China during the former period yet less frequent (−3.6 ± 0.39 day month−1 decade−1) during the latter period; in the Indian subcontinent, more frequent APEEs (+1.1 ± 0.25 day month−1 decade−1) have been detected during the whole period. Consistent with the AOD trends, clear-sky radiation in East China shows a negative trend at the surface (−3.2 ± 0.67 W m−2 decade−1), a positive trend in the atmosphere (+1.4 ± 0.68 decade−1), and a negative trend at the top of the atmosphere (−1.8 ± 0.43 decade−1) during the former period, respectively; opposite trends with much larger magnitude are seen during the latter period. In the Indian subcontinent, the clear-sky radiation trends during the whole period are −1.4 ± 0.38, +1.7 ± 0.31, and + 0.5 ± 0.16 W m−2 decade−1 at the surface, in the atmosphere, and at the top of the atmosphere, respectively. Comparison of radiation trends at clear-sky and all-sky conditions suggests that absorbing aerosols dominate the radiation budget in the atmosphere and the aerosol reanalysis of the Modern-Era Retrospective Analysis for Research ans Applications version 2 (MERRA-2) might overestimate the radiation response to clouds. This study provides an up-to-date analysis of the long-term trends in aerosols and their extreme events and radiation in two of the world's heavily polluted regions and the results have important implications for assessment of the environmental and climatic impacts of the ongoing clean air acts in Asia. • Fewer aerosol pollution extreme events were observed in China in the past decade. • Surface solar radiation increased in China but maintained in India for 2011–2019. • Clean Air Act has improved air quality in China but not in India in the past decade. [ABSTRACT FROM AUTHOR]

Despite much effort made in studying human health associated with fine particulate matter (PM 2.5), our knowledge about PM 2.5 and human health from a long-term perspective is still limited by inadequately long data. Here, we presented a novel method to retrieve surface PM 2.5 mass concentrations using surface visibility measurements and GEOS-Chem model simulations. First, we used visibility measurements and the ratio of PM 2.5 and aerosol extinction coefficient (AEC) in GEOS-Chem to calculate visibility-inferred PM 2.5 at individual stations (SC-PM 2.5). Then we merged SC-PM 2.5 with the spatial pattern of GEOS-Chem modeled PM 2.5 to obtain a gridded PM 2.5 dataset (GC-PM 2.5). We validated the GC-PM 2.5 data over the North China Plain on a 0.3125° longitude x 0.25° latitude grid in January, April, July and October 2014, using ground-based PM 2.5 measurements. The spatial patterns of temporally averaged PM 2.5 mass concentrations are consistent between GC-PM 2.5 and measured data with a correlation coefficient of 0.79 and a linear regression slope of 0.8. The spatial average GC-PM 2.5 data reproduce the day-to-day variation of observed PM 2.5 concentrations with a correlation coefficient of 0.96 and a slope of 1.0. The mean bias is less than 12 μg/m3 (<14%). Future research will validate the proposed method using multi-year data, for purpose of studying long-term PM 2.5 variations and their health impacts since 1980. • We integrate visibility data and GEOS-Chem simulations to estimate PM 2.5 concentrations in 2014 over North China. • Visibility converted PM 2.5 are spatiotemporally consistent with PM 2.5 measurements. • Our method provides a novel, plausible way to retrieve long-term variation of PM 2.5. [ABSTRACT FROM AUTHOR]

• The domain-averaged PM 2.5 in North China decreased significantly from 2013 to 2017. • Firstly established two automatic algorithms to identify regional pollution types and events. • The relationships of synoptic circulations and regional PM 2.5 levels were quantified. • Starting areas, synoptic and local meteorological mechanisms were analyzed based on persistent regional pollution events. • Quantifying the effects of weather changes on the interannual PM 2.5 variations. In the last decade, North China (NC) has been one of the most populated and polluted regions in the world. The regional air pollution has had a serious impact on people's health; thus, all levels of government have implemented various pollution prevention measures since 2013. Based on multi-city in situ environmental and meteorological data, as well as the meteorological reanalysis dataset from 2013 to 2017, regional pollution characteristics and meteorological formation mechanisms were analyzed to provide a more comprehensive understanding of the evolution of PM 2.5 in NC. The domain-averaged PM 2.5 was 79 ± 17 µg m−3 from 2013 to 2017, with a decreasing rate of 10 μg m−3 yr−1. Two automatic computer algorithms were established to identify 6 daily regional pollution types (DRPTs) and 48 persistent regional pollution events (PRPEs) over NC during 2014–2017. The average PM 2.5 concentration for the Large-Region-Pollution type (including the Large-Moderate-Region-Pollution and Large-Severe-Region-Pollution types) was 113 ± 40 µg m−3, and more than half of Large-Region-Pollution days and PRPEs occurred in winter. The PRPEs in NC mainly developed from the area south of Hebei. The number of Large-Region-Pollution days decreased notably from 2014 to 2017, the annual number of days varying between 194 and 97 days, whereas a slight decline was observed in winter. In addition, the averaged PM 2.5 concentrations and the numbers and durations of the PRPEs decreased. Lamb-Jenkinson weather typing was used to reveal the impact of synoptic circulations on PM 2.5 across NC. Generally, the contributions of the variations in circulation to the reduction in PM 2.5 levels over NC between 2013 and 2017 were 64% and 45% in summer and winter, respectively. The three most highly polluted weather types were types C, S and E, with an average PM 2.5 concentration of 137 ± 40 µg m−3 in winter. Furthermore, three typical circulation dynamics were categorized in the peak stage of the PRPEs, namely, the southerly airflow pattern, the northerly airflow pattern and anticyclone pattern; the averaged relative humidity, recirculation index, wind speed and boundary layer height were 63%, 0.33, 2.0 m s−1 and 493 m, respectively. Our results imply that additional emission reduction measures should be implemented under unfavorable meteorological situations to attain ambient air quality standards in the future. [ABSTRACT FROM AUTHOR]

Background: Little is known about the relationship between serum uric acid (SUA) and cardio-ankle vascular index (CAVI) in Chinese population. Therefore, we aimed to investigate the gender difference in the association of SUA and CAVI in a southwestern Chinese population. Methods: Data were obtained from subjects via routine physical examinations in the Public Health Center of our hospital between 2011 and 2014 in Chongqing. The data included completed anthropometry and blood biochemical indicators. The CAVI were recorded using an automatically VaseraVS-1000 vascular screening system. Results: We found females with hyperuricemia (HUA) had significantly higher CAVI than women with normal SUA (8.45 ± 1.40 vs 7.67 ± 1.15, P<0.05). Then we defined high CAVI as CAVI≥9 m/s, and compared the percentage of high CAVI, we found women with HUA had higher percentage of high CAVI than women with normal SUA (26.83% vs 9.38%, P<0.05). Those differences were not significant in males. Also, the logistic regression analysis found age and hypertension were major independent risk factors associated with high CAVI in both genders. HUA and hyperglycemia were independently associated with high CAVI in females with an OR of 3.65, 95%CI (1.37-9.73) and 3.02, 95%CI (1.38-6.63) respectively. However, these significant associations were not be found in males. Conclusions: Our data showed positive associations between elevated SUA levels and higher CAVI risk in the inland Chinese females, but not in males. The reason for the gender differences were still unclear, sex hormones may play a role. Further prospective studies including detailed personal information and multicenter were required. [ABSTRACT FROM AUTHOR]