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Multifunctional therapeutics have emerged as a solution to the constraints imposed by drugs with singular or insufficient therapeutic effects. The primary challenge is to integrate diverse pharmacophores within a single-molecule framework. To address this, we introduced DeepSA, a novel edit-based generative framework that utilizes deep simulated annealing for the modification of articaine, a well-known local anesthetic. DeepSA integrates deep neural networks into metaheuristics, effectively constraining molecular space during compound generation. This framework employs a sophisticated objective function that accounts for scaffold preservation, anti-inflammatory properties, and covalent constraints. Through a sequence of local editing to navigate the molecular space, DeepSA successfully identified AT-17, a derivative exhibiting potent analgesic properties and significant anti-inflammatory activity in various animal models. Mechanistic insights into AT-17 revealed its dual mode of action: selective inhibition of NaV1.7 and 1.8 channels, contributing to its prolonged local anesthetic effects, and suppression of inflammatory mediators via modulation of the NLRP3 inflammasome pathway. These findings not only highlight the efficacy of AT-17 as a multifunctional drug candidate but also highlight the potential of DeepSA in facilitating AI-enhanced drug discovery, particularly within stringent chemical constraints.

In recent years, China's advanced light sources have entered a period of rapid construction and development. As modern X-ray detectors and data acquisition technologies advance, these facilities are expected to generate massive volumes of data annually, presenting significant challenges in data management and utilization. These challenges encompass data storage, metadata handling, data transfer and user data access. In response, the Data Organization Management Access Software (DOMAS) has been designed as a framework to address these issues. DOMAS encapsulates four fundamental modules of data management software, including metadata catalogue, metadata acquisition, data transfer and data service. For light source facilities, building a data management system only requires parameter configuration and minimal code development within DOMAS. This paper firstly discusses the development of advanced light sources in China and the associated demands and challenges in data management, prompting a reconsideration of data management software framework design. It then outlines the architecture of the framework, detailing its components and functions. Lastly, it highlights the application progress and effectiveness of DOMAS when deployed for the High Energy Photon Source (HEPS) and Beijing Synchrotron Radiation Facility (BSRF).

State-of-health (SOH) estimation of lithium-ion batteries stands as a fundamental metric within the battery management system. It reflects the current level of battery aging and is important for early warning of battery failure to avoid unsafe battery behavior. Therefore, accurate SOH estimation can ensure safe and reliable battery operation. In this paper, the capacity data of the discharge phase are used as the input of the SOH estimation model, and a gray wolf optimization (GWO)–variable mode decomposition (VMD)-transformer-based SOH estimation method for lithium-ion batteries is proposed in a data-driven framework. First, the GWO algorithm is adopted to optimize VMD to decompose the original battery capacity degradation sequence into a series of intrinsic mode functions (IMFs). Then, the transformer is used to separately predict each of these IMFs. Finally, the predicted values of each IMF are integrated to obtain the final prediction of the battery capacity degradation sequence. The model undergoes testing across various datasets, and comparative evaluations are conducted against other data-driven prediction models. The experimental findings underscore the superior SOH estimation performance of the proposed method, along with its robustness when confronted with diverse types of lithium-ion batteries, spanning distinct operational conditions and different aging degrees.

Abstract Objectives To compare the efficacy, overall survival (OS) and safety of drug-eluting beads-TACE (DEB-TACE) and C-TACE as initial treatment in advanced hepatocellular carcinoma (HCC) patients with main portal vein tumor thrombus (mPVTT). Methods The medical records of consecutive advanced HCC patients with mPVTT who underwent initial DEB-TACE or C-TACE from September 2015 to October 2021 were retrospectively evaluated. Treatment crossover was allowed in this retrospective research. The adverse events, disease control rate (DCR), time to tumor progression (TTP) and OS of patients who underwent DEB-TACE were compared with those of patients who underwent C-TACE. Results Eighty-three patients were included: 42 patients in DEB-TACE group and 41 patients in C-TACE group. DEB-TACE could be safely performed in HCC patients with mPVTT, and they gained a better DCR than those submitted to the C-TACE (76.2% vs. 53.7%, P = 0.031), which might have resulted in longer TTP (median TTP: 9.0 months vs. 3.0 months, P

Background: Hypoxia has been shown to induce cancer cells to become dormant meanwhile these cells inclined to disseminate and eventually cause metastasis. However, the molecular mechanism is still elusive. The purpose is to explore whether dormancy-associated microRNAs (DmiRs) get involved in hypoxia-induced cell dormancy of salivary adenoid cystic carcinoma (SACC). Material and Methods: This study performed multi-perspective investigation of the biological effects of miR-922/DEC2 on SACC based on clinical samples, 2D and 3D in vitro model and nude mice in vivo model, based on our previous study of overexpression of DEC2 inducing SACC cellular dormancy. Results: According to the existing microRNA array of SACC tissue, we found that miR-922 was upregulated in SACC tissue and was inversely correlated with DEC2, suggesting that miR-922 might participate in the activation of SACC cell dormancy as a DmiR. Then, we found miR-922 low SACC cells exhibited cell dormancy and a low level of fatty acid oxidation with propensity for lipid droplets accumulation through DEC2. Moreover, HIF1a downregulated the level of miR-922 to induce SACC cell dormancy. In addition, in xenografts of nude mice the inhibition of miR-922 attenuated the growth of primary tumor and the lung metastasis of SACC. Conclusions: miR-922/DEC2 axis was necessary to hypoxia-induced cell dormancy and played an important role in the lipid metabolism reprogramming of SACC.

Background Although the roles of PD-L1 in promoting tumor escape from immunosurveillance have been extensively addressed, its non-immune effects on tumor cells remain unclear.Methods The spatial heterogeneity of PD-L1 staining in human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) tissues was identified by immunohistochemistry. Three-dimensional (3D) specific cell-led invasion assay and 3D cancer spheroid model were used to investigate the roles of PD-L1hileader cells in collective invasion. The impact of M1 macrophages on specific PD-L1 expression in leader cells and its mechanisms were further studied. Finally, the effect of combination therapy of anti-PD-L1 and CDK4 inhibitor on HPV-positive tumors were evaluated on a mice model.Results Here, we observed a distinctive marginal pattern of PD-L1 expression in HPV-positive HNSCC tissues. By mimicking this spatial pattern of PD-L1 expression in the 3D invasion assay, we found that PD-L1hi cells led the tumor collective invasion. M1 macrophages induced specific PD-L1 expression in leader cells, and depletion of macrophages in tumor-bearing mice abrogated PD-L1hileader cells and collective invasion. Mechanistically, TNF-α secreted by M1 macrophages markedly increased the abundance of PD-L1 via CDK4/ubiquitin-specific peptidase 14-mediated deubiquitination of PD-L1. We also found that suppression of CDK4 enhanced the efficacy of anti-PD-L1 therapy in an E6/E7 murine model.Conclusions Our study identified TNF-α/CDK4/ubiquitin-specific peptidase 14-mediated PD-L1 stability as a novel mechanism underlying M1 macrophage-induced PD-L1hileader cells and collective tumor invasion, and highlighted the potential of the combination therapy of anti-PD-L1 and CDK4 inhibitor for HPV-positive HNSCC.

Abstract Spinal cord injury (SCI) can result in irreversible sensory and motor disability with no effective treatment currently. After SCI, infiltrated macrophages accumulate in epicenter through destructed blood-spinal cord barrier (BSCB). Further, great majority of macrophages are preferentially polarized to M1 phenotype, with only a few transient M2 phenotype. The purpose of this study was to explore roles of vascular endothelial cells in microglia/macrophages polarization and the underlying mechanism. Lipopolysaccharide (LPS) was used to pretreat BV2 microglia and RAW264.7 macrophages followed by administration of conditioned medium from microvascular endothelial cell line bEnd.3 cells (ECM). Analyses were then performed to determine the effects of exosomes on microglia/macrophages polarization and mitochondrial function. The findings demonstrated that administration of ECM shifted microglia/macrophages towards M2 polarization, ameliorated mitochondrial impairment, and reduced reactive oxygen species (ROS) production in vitro. Notably, administration of GW4869, an exosomal secretion inhibitor, significantly reversed these observed benefits. Further results revealed that exosomes derived from bEnd.3 cells (Exos) promote motor rehabilitation and M2 polarization of microglia/macrophages in vivo. Ubiquitin-specific protease 13 (USP13) was shown to be significantly enriched in BV2 microglia treated with Exos. USP13 binds to, deubiquitinates and stabilizes the NF-κB inhibitor alpha (IκBα), thus regulating microglia/macrophages polarization. Administration of the selective IκBα inhibitor betulinic acid (BA) inhibited the beneficial effect of Exos in vivo. These findings uncovered the potential mechanism underlying the communications between vascular endothelial cells and microglia/macrophages after SCI. In addition, this study indicates exosomes might be a promising therapeutic strategy for SCI treatment.

Background The incidence and mortality of hepatocellular carcinoma (HCC) had increased globally over the past decades. Previous studies found that transarterial chemoembolization (TACE) combined with lenvatinib had also shown efficacy in the unresectable HCC. We aimed to evaluate the safety and efficacy of TACE combined with lenvatinib and camrelizumab to treat unresectable multiple nodular and large HCC (>5 cm). Materials and methods Between November 2018 and June 2021, we retrospectively recruited 82 patients with unresectable multiple nodular and large HCC (BCLC stage B or C with a single nodular diameter of >5 cm). Of the patients who had not previously been treated, 33 patients received TACE + lenvatinib + camrelizumab (group A, TLC), and 49 patients treated with TACE + lenvatinib (group B, TLB) as the initial treatment. Related efficacy and safety results were recorded and assessed. Results The median follow-up periods of groups A and B were 14.5 ± 7.9 months (range, 3-36) and 12.5 ± 8.2 months (range, 3-32), respectively (P = 0.799). The progression-free survival (PFS) of groups A and B was 9.4 months and 5.9 months (P 5 cm), TACE combined with target therapy and immunotherapy is safe and effective.

Background and aim: Percutaneous transhepatic biliary drainage (PTBD) does not always lead to a reduction in serum total bilirubin (TBil) level in patients with hepatocellular carcinoma and obstructive jaundice. We aimed to develop a model for pre-PTBD prediction of post-procedural TBil decrease in these patients. Materials and methods: Retrospective database searches were conducted at four teaching hospitals (reference period: January 2010 to December 2018), and baseline characteristics of eligible patients were extracted. Any decrease in TBil after PTBD and the lowest level of TBil post-PTBD

Abstract Background Conventional-transarterial chemoembolization (C-TACE) was proven to improve overall survival (OS) in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombus (PVTT), drug-eluting microsphere-TACE (DEM-TACE) was supposed to provide more benefit than C-TACE in this respect. Purpose To compare the safety and efficacy between DEM-TACE and C-TACE as the initial treatment in HCC patients with PVTT and to identify prognostic factors of OS. Methods The medical records of advanced HCC patients with PVTT who underwent DEM-TACE or C-TACE as the initial thearpy from September 2015 with mean follow-up time 14.9 ± 1.2 (95% CI 12.6–17.2) months were retrospectively evaluated. A total of 97 patients were included, 49 patients in the DEM-TACE group and 48 in the C-TACE group. Adverse events (AEs) related to TACE were compared. Tumor and PVTT radiologic response, time to tumor progression (TTP) and OS were calculated and compared in both groups. Results Patients in DEM-TACE group had a better radiologic response (Tumr response: 89.8% vs. 75.0%; PVTT response: 85.7% vs. 70.8%; overall response: 79.6% vs. 58.3%, P = 0.024) and longer TTP (7.0 months vs. 4.0 months, P = 0.040) than patients in C-TACE group. A lower incidence of abdominal pain was found in the DEM-TACE group than in C-TACE group (21 vs. 31, P = 0.032), but there were no significant differences between DEM-TACE and C-TACE patients in any other AEs reported. When compared to C-TACE, DEM-TACE also showed significant OS benefits (12.0 months vs. 9.0 months, P = 0.027). DEM-TACE treatment, the absence of arterioportal shunt (APS), lower AFP value and better PVTT radiologic response were the independent prognostic factors for OS in univariate/multivariate analyses, which provided us with a guide for better patient selection. Conclusions Based on our retrospective study, DEM-TACE can be performed safely and might be superior to C-TACE as the initial treatment for HCC patients with PVTT. Trial registration Retrospectively registered.

Abstract The uptake of hexavalent chromium (Cr(VI)) ions from wastewater is of great significance for environmental remediation and resource utilization. In this study, a self‐designed instrument equipped with an oxidized mesoporous carbon monolith (o‐MCM) as an electro‐adsorbent is developed. o‐MCM with a super hydrophilic surface displayed a high specific surface area (up to 686.5 m2 g−1). With the assistance of an electric field (0.5 V), the removal capacity of Cr(VI) ions is as high as 126.6 mg g−1, much higher than that without an electric field (49.5 mg g−1). During this process, no reduction reaction of Cr(VI) to Cr(III) ions is observed. After adsorption, the reverse electrode with 10 V is used to efficiently desorb the ions on the carbon surface. Meanwhile, the in situ regeneration of carbon adsorbents can be obtained even after ten recycles. On this basis, the enrichment of Cr(VI) ions in a special solution is achieved with the assistance of an electric field. This work lays a foundation for the uptake of heavy metal ions from wastewater with the assistance of the electric field.

In this study, a portable spectral analysis instrument based on spontaneous emission spectroscopy (SES) was developed for the in situ, non-intrusive, and quantitative measurement of gaseous Na inside ZD coal-fired boilers, which is mainly applied for predicting slagging in furnaces. This technology is needed urgently because the problem of fouling and slagging caused by high alkali metals in ZD coal restricts the rational utilization of this coal. The relative extended uncertainty for the measurement of gaseous Na concentration is Urel = 10%, k = 2, which indicates that measurement data are reliable under working conditions. It was found that there is a clear linear relationship between the concentration of gaseous Na and fouling in high-alkali coal boilers. Therefore, a fast and efficient method for predicting the slagging and fouling of high-alkali coal boilers can be established by using this in situ online real-time optical measurement.

The large-scale deployment of carbon capture and storage (CCS) is becoming increasingly urgent in the global path toward net zero emissions; however, global CCS deployment is significantly lagging behind its expected contribution to greenhouse gas emission reduction. Reviewing and learning from the examples and history of successful CCS practices in advanced countries will help other countries, including China, to promote and deploy CCS projects using scientific methods. This paper shows that the establishment of major science and technology CCS infrastructures in advanced countries has become the main source of CCS technological innovation, cost reduction, risk reduction, commercial promotion, and talent training in the development and demonstration of key CCS technologies. Sound development of CCS requires a transition from pilot-scale science and technology infrastructures to large-scale commercial infrastructures, in addition to incentive policies; otherwise, it will be difficult to overcome the technical barriers between small-scale demonstrations and the implementation of million-tonne-scale CCS and ten-million-tonne-scale CCS hubs. Geological CO2 storage is the ultimate goal of CCS projects and the driving force of CO2 capture. Further improving the accuracy of technologies for the measurement, monitoring, and verification (MMV) of CO2 storage capacity, emission reduction, and safety remains a problem for geological storage. CO2 storage in saline aquifers can better couple multiple carbon emission sources and is currently a priority direction for development. Reducing the energy consumption of low-concentration CO2 capture and the depletion of chemical absorbents and improving the operational efficiency and stability of post-combustion CO2 capture systems have become the key constraints to large-scale CCS deployment. Enhanced oil recovery (EOR) is also important in order for countries to maximize fossil fuel extraction instead of importing oil from less environmentally friendly oil-producing countries.

Accurate characterization of land use and land cover changes (LULCC) is essential for numerical models to capture LULCC-induced effects on regional meteorology and air quality, while outdated LULC dataset largely limits model capability in reproducing land surface parameters, particularly for complex terrain. In this study, we incorporate land cover data from MODIS in 2019 into the Weather Research and Forecasting (WRF) model to simulate the impacts of LULC on meteorological parameters over the Sichuan Basin (SCB). Further, we conduct Community Multiscale Air Quality (CMAQ) simulations with WRF default LULC and MODIS 2019 to probe the effects on regional air quality. Despite consistency found between meteorological observations and WRF-CMAQ simulations, the default WRF land cover data does not accurately capture rapid urbanization over time compared with MODIS. Modeling results indicate that magnitude changes trigged by LULCC are highly varied across SCB and the impacts of LULCC are more pronounced over extended metropolitan areas due to alteration by urbanization, featured by elevating 2-m temperature up to 2°C and increased planetary boundary layer height (PBLH) up to 400 m. For air quality implications, it is found that LULCC leads to basin-wide O3 enhancements with maximum reaching 21.6 μg/m3 and 57.2 μg/m3 in the daytime and nighttime, respectively, which is mainly attributed to weakening NOx titration effects at night. This work contributes modeling insights into quantitative assessment for impacts of LULCC on regional meteorology and air quality which pinpoints optimization of the meteorology-air quality model.

Rapid urbanization has the potential to fundamentally perturb energy budget and alter urban air quality. While it is clear that urban meteorological parameters are sensitive to urbanization-induced changes in landscapes, a gap exists in our knowledge about how changes in land use and land cover affect the dynamics of urban air quality. Herein, we simulated a severe O3 episode (10–16 July 2017) and a highly polluted PM2.5 episode (25–30 December 2017) and assessed the changes of meteorological phenomenon and evolution of air pollutants induced by urbanization. We found that the urban expansion area (i.e., land use transition from natural to urban surfaces between 2000 and 2017, UEA) has a significant increase in nocturnal 2-m temperature (T2) with maximum values reaching 3 and 4°C in summer and winter, respectively. In contrast, UEA experienced cooling in the daytime with stronger reductions of T2 in winter than in summer. The T2 variability is primarily attributed to the intense thermal inertia and high heat capacity of the urban canopy and the shadowing effect caused by urbanization. Owing to increased surface roughness and decreased surface albedo as well as shadowing effects, the ventilation index (VI) of UEA increased up to 1,200 m2/s in winter while decreased up to 950 m2/s in summer. Changes in meteorological phenomenon alter physical and chemical processes associated with variations in PM2.5 and O3 concentrations. Urbanization leads to enhanced vertical advection process and weakened aerosol production, subsequently causing PM2.5 levels to decrease by 33.2 μg/m3 during the day and 4.6 μg/m3 at night, respectively. Meanwhile, O3 levels increased by 61.4 μg/m3 at 20:00 due to the reduction of horizontal advection induced by urbanization, while O3 concentrations changed insignificantly at other times. This work provides valuable insights into the effects of urbanization on urban meteorology and air quality over typical megacities, which support informed decision-making for urban heat and air pollution mitigation.

Head and neck squamous cell carcinomas (HNSCCs) are closely linked with immunosuppression, accompanied by complex immune cell functional activities. The abnormal competition between costimulatory and coinhibitory signal molecules plays an important role in the malignant progression of HNSCC. This review will summarize the features of costimulatory molecules (including CD137, OX40 as well as CD40) and coinhibitory molecules (including CTLA-4, PD-1, LAG3, and TIM3), analyze the underlying mechanism behind these molecules' regulation of the progression of HNSCC, and introduce the clinic application. Vaccines, such as those targeting STING while working synergistically with monoclonal antibodies, are also discussed. A deep understanding of the tumor immune landscape will help find new and improved tumor immunotherapy for HNSCC.

After the national "30.60" carbon peaking and carbon neutrality goals were proposed, Yulin City in Shaanxi Province, an important energy base in China, came under intense pressure to reduce emissions because of its rich fossil energy reserves and large number of coal chemical and coalfired power plant enterprises. As a result, it urgently needs to switch from high emission to low carbon. In this paper a four-dimensional seismic forward modeling is established to prove that the geological conditions of the area are suitable for CO2 geological storage and CO2 can be monitored in this area. Then the CO2 emissions of major industrial parks and counties in Shaanxi Province were summarized the Yulin City's current CO2 capture, utilization, and storage (CCUS) industrial chain was organized. Last but not least, the following recommendations were made for the development of the CCUS cluster in Yulin: (1) Yulin is appropriate for large-scale CO2 capturing activities due to its highly concentrated emissions and matured CO2 capturing technology. (2) Since the cost of transporting CO2 to its storage location by tank truck is significant, it is suggested that a pipeline be constructed to transport the gas in order to reduce costs. (3) Despite the promise of CO2-EOR (CO2-enhanced oil recovery) in Yulin, geological storage in a deep saline aquifer close by is now the preferred method due to the emission source's distance from the oilfield. (4) Two CO2 geological storage demonstration projects in Yulin City are still centered on oil displacement at the moment. It is necessary to conduct surveillance research on the volume of CO2 storage and use the CCUS method to define the accounting boundary. Yulin's geological sequestration of CO2 is now too small to satisfy the urgent requirement for significant emission reductions. It is vital to draw lessons from industrialized nations' experience, establish scientific research institutions for CO2 geological sequestration, and then design innovative and motivating policies in technology, supply chains, and commercial models that can extend the CCUS scale. [ABSTRACT FROM AUTHOR]

Despite significant advancements in improving the dataset for biomass burning (BB) emissions over the past few decades, uncertainties persist in BB aerosol emissions, impeding the accurate assessment of simulated aerosol optical properties (AOPs) and direct radiative forcing (DRF) during wildfire events in global and regional models. This study assessed AOPs (including aerosol optical depth (AOD), aerosol absorption optical depth (AAOD), and aerosol extinction coefficients (AEC)) and DRF using eight independent BB emission inventories applied to the WRF-Chem model during the BB period (March 2019) in Peninsular Southeast Asia (PSEA), where the eight BB emission inventories were the Global Fire Emissions Database version 4.1s (GFED), Fire INventory from NCAR version 1.5 (FINN1.5), the Fire Inventory from NCAR version 2.5 MOS (MODIS fire detections, FINN2.5 MOS), the Fire Inventory from NCAR version 2.5 MOSVIS (MODIS+VIIRS fire detections, FINN2.5 MOSVIS), Global Fire Assimilation System version 1.2s (GFAS), Fire Energetics and Emissions Research version 1.0 (FEER), Quick Fire Emissions Dataset version 2.5 release 1 (QFED), and Integrated Monitoring and Modelling System for Wildland FIRES Project version 2.0 (IS4FIRES), respectively. The results show that in the PSEA region, organic carbon (OC) emissions in the eight BB emission inventories differ by a factor of about 9 (0.295–2.533 Tg/M), with 1.09 ± 0.83 Tg/M and a coefficient of variation (CV) of 76 %. High-concentration OC emissions occurred primarily in savanna and agricultural fires. The OC emissions from the GFED and GFAS are significantly lower than the other inventories. The OC emissions in FINN2.5 VISMOS are approximately twice as high as those in FINN1.5. Sensitivity analysis of AOD simulated by WRF-Chem to different BB emission datasets indicated that the FINN scenarios (v1.5 and 2.5) significantly overestimate AOD compared to observation (VIIRS), while the other inventories underestimate AOD in the high AOD (HAOD, AOD>1) regions range from 97–110° E, 15–22.5° N. Among the eight schemes, IS4FIRES and FINN1.5 performed better in terms of AOD simulation consistency and bias in the HAOD region when compared to AERONET sites. The AAOD in WRF-Chem during the PSEA wildfire period was assessed using satellite observations (TROPOMI) and AERONET data, and it was found that the AAOD simulated with different BB schemes did not perform as well as the AOD. The significant overestimation of AAOD by FINN (v1.5 and 2.5), FEER, and IS4FIRES schemes in the HAOD region, with the largest overestimation for FINN2.5 MOSVIS. FINN1.5 schemes performed better in representing AAOD at AERONET sites within the HAOD region. The simulated AOD and AAOD from FINN2.5 MOSVIS always show the best correlation with the observations. AEC simulated by WRF-Chem with all the eight BB schemes trends were consistent with CALIPSO in the vertical direction (0.5 km to 4 km), demonstrating the efficacy of the smoke plume rise model used in WRF-Chem to simulate smoke plume heights. However, the FINN (v1.5 and 2.5) schemes overestimated AEC, while the other schemes underestimated it. In the HAOD region, BB aerosols exhibited a daytime shortwave radiative forcing of -32.60±24.50 W/m² at the surface, positive forcing (1.70±1.40 W/m²) in the atmosphere, and negative forcing (-30.89±23.6 W/m²) at the top of the atmosphere. Based on the analysis, FINN1.5 and IS4FIRES are recommended for accurately assessing the impact of BB on air quality and climate in the PSEA region. [ABSTRACT FROM AUTHOR]

Reactive chlorine species play a crucial role as precursors to Cl radicals, which can significantly impact the atmospheric oxidation capacity and influence the levels of trace gases related to climate and air quality. However, their anthropogenic sources remain uncertain and require further investigation. In previous studies, we developed the Anthropogenic Chlorine Emission Inventory for China (ACEIC) for the years 2012 and 2014. This inventory focused solely on the emissions of hydrogen chloride (HCl) and chlorine gas (Cl2) from coal combustion and prescribed waste incineration. In the present study, we updated this inventory to include data from a more recent year (2018) and expanded the range of species considered (HCl, fine particulate Cl-, Cl2, and hypochlorous acid (HOCl)) as well as the number of anthropogenic sources (41 specific sources). The emission factors used in this updated inventory were primarily based on localized survey data. The total emissions of HCl, fine particulate Cl-, Cl2, and HOCl in mainland China for the year 2018 were estimated to be 454 (- 48%~45%), 238 (-59%~89%), 17 (-44%~58%), and 73 (-44%~79%) Gg, respectively. To facilitate analysis, we aggregated the chlorine emissions from various sources into five economic sectors: power, industry, residential, agriculture, and biomass burning. HCl emissions were primarily derived from biomass burning (45%), industry (35%), and residential (15%) sectors. The biomass burning and industry sectors accounted for 78% and 14% of the fine particulate Cl- emissions, respectively. Residential and industry sectors contributed 59% and 31% of the total Cl2 emissions. HOCl emissions were predominantly from the residential sector, constituting 90% of the total emissions. Notably, the usage of chlorine-containing disinfectants was identified as the most significant source of Cl2 and HOCl emissions in the residential sector. Geographically, regions with high HCl and fine particulate Cl- emissions were found in northeast China, the North China Plain, and the Sichuan Basin, whereas the Pearl River Delta, Yangtze River Delta, and Beijing-Tianjin-Hebei regions exhibited elevated levels of Cl2 and HOCl emissions. Regarding monthly variation, emissions of HCl and fine particulate Cl- were relatively higher during early summer (June-July) and October due to intensified agricultural activities, while Cl2 and HOCl emissions were higher in the summer months due to increased demand for water disinfection. This updated inventory contributes to a better understanding of anthropogenic sources of reactive chlorine species and can aid in the formulation of emission control strategies to mitigate secondary pollution in China. [ABSTRACT FROM AUTHOR]

Nighttime ozone in the lower boundary layer regulates atmospheric chemistry and surface ozone air quality, but our understanding of its vertical structure and impact is largely limited by the extreme sparsity of direct measurements. Here we present 3-year (2017-2019) measurements of ozone in the lower boundary layer (up to 500 m) from the Canton Tower at Guangzhou, the core megacity in South China, and interpret the measurements with a one-month high-resolution chemical simulation from the Community Multiscale Air Quality (CMAQ) model. Measurements are available at 10 m, 118 m, 168 m, and 488 m, with the highest 488 m measurement platform higher than the typical height of nighttime stable boundary layer that allows direct measurements of ozone in the nighttime residual layer (RL). We find that ozone increases with altitude in the lower boundary layer throughout the day, with nighttime (daytime) ozone at the 488 m height being 2.4-5.4 (1.5-2.4) times as that at the 10 m height. This indicates a persistent high ozone level and oxidation capacity aloft the surface. The ozone vertical gradient between the 10 m and 488 m height (ΔO3/ΔH10-488 m) is 3.6-6.4 ppbv/hm in nighttime and 4.4-5.8 ppbv/hm daytime. We identify a strong ozone residual capacity, defined as the ratio of the ozone concentration averaged over nighttime to that in the afternoon (14:00-17:00 LT), of 67%-90% in January, April and October, remarkably higher than that in the other three layers (29%-51%). Ozone in the afternoon convective mixing layer provides the source of ozone in the RL, and strong temperature inversion facilitates the ability of RL to store ozone from the daytime convective mixing layer, by constraining the exchange of RL ozone with ozone inside the nocturnal stable boundary layer that is subject to strong chemical destruction and deposition. The tower-based measurement also indicates that nighttime surface Ox (Ox=O3+NO2) level can be an effective indicator of RL ozone if direct measurement is not available. We further find significant influences of nocturnal RL ozone on both nighttime and the following day's daytime surface ozone air quality. During the surface nighttime ozone enhancement (NOE) event, we observe significant decrease in ozone and increase in NO2 and CO at the 488 m height, in contrast to their changes at the surface, a typical feature of enhanced vertical mixing. The enhanced vertical mixing leads to NOE event by introducing ozone-rich air in the RL to enter the nighttime stable boundary layer and weakens the titration effect by diluting NOx concentrations. The CMAQ model simulations also demonstrate enhanced positive contribution of vertical diffusion (ΔVDIF) to ozone at the 10 m and 118 m and negative contribution at the 168 m and 488 m during the NOE event. We also observe strong correlation between nighttime RL ozone and the following day's surface MDA8 ozone. This is tied to enhanced vertical mixing with the collapse of nighttime RL and the development of convective mixing layer, which is supported by the CMAQ simulated increase in positive ΔVDIF of +50 ppbv⋅hr-1 at the 10 m and negative ΔVDIF of -10 ppbv⋅hr-1 at 488 m at early morning (08:00-09:00 LT), suggesting that the mixing of ozone-rich air from nighttime RL downward to surface via the entrainment is an important mechanism to aggravate ozone pollution in the following day. We find that the bias of CMAQ simulated surface MDA8 ozone in the following day shows a strong correlation coefficient (r=0.74) with the bias in nighttime ozone in the RL, highlighting the necessity to correct air quality model bias in the nighttime RL ozone for accurate prediction of daytime ozone. Our study thus highlights the value of long-term tower-based measurements for understanding the coupling between nighttime ozone in the RL, surface ozone air quality, and boundary layer dynamics. [ABSTRACT FROM AUTHOR]