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In recent years, nocturnal ozone enhancement (NOE) events have emerged as a prominent research focus in the field of the atmospheric environment. By using statistical analysis methods, we conducted a comparative investigation of nocturnal ozone concentrations and NOE events in Dongying, the central city of the Yellow River Delta, China, in 2022 and 2023, and further explored the effects of NOE events on O3 and PM2.5 on the same night and the subsequent day. The results showed that from 2022 to 2023, in Dongying, the annual average nocturnal ozone concentrations increased from 51 μg/m3 to 59 μg/m3, and the frequency of NOE events was higher in the spring, summer, and autumn, and lower in the winter. The NOE events not only exhibited promoting effects on nocturnal O3 and Ox, and on the daily maximum 8 h average concentration of O3 (MDA8-O3) on the same day (comparatively noticeable in summer and autumn), but also demonstrated a clear impact on nocturnal PM2.5 and PM2.5-bounded NO3− and SO42− (especially in winter). Additionally, the NOE events also led to higher concentrations of O3 and Ox, as well as higher MDA8-O3 levels during the subsequent day, with more observable impacts in the summer. The results could strengthen our understanding about NOE events and provide a scientific basis for the collaborative control of PM2.5 and O3 in urban areas in the Yellow River Delta in China. [ABSTRACT FROM AUTHOR]

• A single-dose priming vaccination with the bivalent adenovirus-vectored vaccine (Ad5-nCoV/O) induced strong antibody and cellular responses against both the wild type and Omicron variants of SARS-CoV-2. • Both intramuscular and intranasal booster vaccinations using the bivalent Ad5-nCoV/O vaccine resulted in significant serum neutralizing antibody responses. • An intranasal booster, utilizing one-fifth doses of the bivalent Ad5-nCoV/O vaccine after priming with INA, elicited similar levels of neutralizing antibody titers as the intramuscular booster. • Heterologous prime-boost vaccination with Ad5-vectored vaccines after the inactivated vaccine (INA) prime demonstrated higher neutralizing antibody responses compared to homologous prime-boost with INA and INA. The emergence and rapid spread of new mutant strains of SARS-CoV-2 necessitate the development of a new generation vaccine capable of neutralizing a broad range of variants. When the SARS-CoV-2 Omicron variant emerged, individuals in China had already received an inactivated (INA) or a type 5 adenovirus-vectored (Ad5) SARS-CoV-2 vaccine targeting the wild-type virus. We have recently developed a bivalent recombinant type 5 vaccine targeting both the wild-type strain and the Omicron variant (Ad5-nCoV/O). The objectives of this study were to assess the immunogenicity of the bivalent vaccine as a booster against both the wild type and the Omicron variant. In the single immunization model, mice received one intramuscular immunization with monovalent or bivalent Ad5-vectored vaccines targeting both wild-type SARS-CoV-2 and Omicron variants. In the prime-boost model, mice were primed intramuscularly with an INA or Ad5-vectored vaccine targeting wild-type SARS-CoV-2, and then boosted intramuscularly or intranasally with heterologous or homologous INA or monovalent or bivalent Ad5-vectored vaccines targeting both wild-type SARS-CoV-2 and Omicron variants. The vaccine-induced antibody responses and cellular immune responses were measured using ELISA, pseudovirus-based neutralization assays, the intracellular cytokine staining (ICS) and ELISpot. Single-dose prime vaccination with the monovalent and bivalent vaccines elicited robust antibody responses and CD4 + and CD8 + cellular responses against the spike protein of WT and Omicron SARS-CoV-2. Both intramuscular and intranasal boost vaccination with the bivalent Ad5-nCoV/O following a prime with INA or Ad5-vectored vaccines induced strong serum neutralization antibody responses to both wild type and Omicron variants. A heterologous prime-boost vaccination elicited greater neutralization antibody responses than a homologous prime-boost vaccination when mice were boosted with Ad5-vectored vaccines following a prime with INA. Intranasal boost also resulted in significant mucosal IgA responses. The bivalent vaccine Ad5-nCoV/O exhibited robust immunogenicity, inducing broad-spectrum cross-neutralizing antibodies and cellular immune responses against both wild type and Omicron variants of SARS-CoV-2. The results demonstrated the potential of the bivalent vaccine in addressing the challenges posed by emerging SARS-CoV-2 Omicron variants. [ABSTRACT FROM AUTHOR]

In order to investigate the causes of complex air pollution in coastal cities in the Bohai Rim of China, a one-month intensive field observation combined with model simulation was carried out in a typical city named Dongying in September 2022. The results showed that two PM2.5 and O3 complex pollution episodes occurred in Dongying in the observation period, with the primary pollutant being O3. Atmospheric photochemical reactions occurring under unfavorable meteorological conditions led to the production of O3 while at the same time facilitating the generation of nitrate, sulfate, and other secondary components of PM2.5 by enhancing the atmospheric oxidizing capacity, which promoted the formation of complex air pollution. It was worth noting that in the context of high pollutants emission, the occurrence of complex air pollution was more sensitive to the variation in meteorological conditions than to the change in pollutants emission. To continuously improve air quality and protect human health in Dongying, it is recommended that an effective regional joint air pollution prevention and control mechanism with neighboring cities should be established in the premise of effective local pollutants reduction, and special attention should be paid to the adverse effect of the air mass transportation from Bohai Bay. [ABSTRACT FROM AUTHOR]

In recent years, the concentrations of PM2.5 in urban ambient air in China have been declining; however, the strong atmospheric oxidation capacity (AOC) represents challenges to the further reduction of PM2.5 concentration and the continuous improvement of ambient air quality in China in the future, since the overall AOC is still at a high level. For this paper, based on ground observation data recorded in Beijing from 2016 to 2019, the variation in AOC was characterized according to the concentration of odd oxygen (OX = O3 + NO2). The concentrations of the primary and secondary components of PM2.5 were analyzed using empirical formulas, the correlation between AOC and the concentrations of secondary PM2.5 and the secondary inorganic components (SO42−, NO3−, NH4+, and SNA) in Beijing were explored, the impact of atmospheric photochemical reaction activity on the generation of atmospheric secondary particles was evaluated, and the impact of atmospheric oxidation variations on PM2.5 concentrations and SNA in Beijing was investigated. The results revealed that OX concentrations reached their peak in 2016 and reached their lowest point in 2019. The OX concentrations followed a descending seasonal trend of summer, spring, autumn, and winter, along with a spatial descending trend from urban observation stations to suburban stations and background stations. The degree of photochemical activity and the magnitude of the AOC have a large influence on the production of atmospheric secondary particles. When the photochemical reaction was more active and the AOC was stronger, the mass concentrations of the secondary generated PM2.5 fraction were higher and accounted for a higher proportion of the total PM2.5 mass concentrations. In the PM2.5 fraction, SNA accounted for 50.7% to 94.4% of the total mass concentrations of water-soluble inorganic ions in the field observations. Higher concentrations of the atmospheric oxidant OX in ambient air corresponded to a higher sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR), suggesting that the increase in AOC could promote the increase of PM2.5 concentration. Based on a relationship analysis of SOR, NOR, and OX, it was inferred that the relationship between OX and SOR and the relationship between OX and NOR were both nonlinear. Therefore, when establishing PM2.5 control strategies in Beijing in the future, the impact of the AOC on PM2.5 generation should be fully considered, and favorable measures should be taken to properly regulate the AOC, which would be more effective when carrying out further control measures regarding PM2.5 pollution. [ABSTRACT FROM AUTHOR]

Birds are valued in the traditional cultures of Tibetan areas of China for symbolism, spirituality, and medicine. A total of 329 informants from six Tibetan communities were interviewed through ethnobiological survey methods. Results highlight that Tibetan informants value a diversity of birds for multiple symbolic purposes including spirituality, a good harvest, happiness, fortune, beauty, glory, and omens. Over 20 avian species including eagles, crows, pheasants, and red-breasted parakeets were perceived as totems, taboos, and holy birds. Findings revealed that three vulture species (Gyps himalayensis, Gyps fulvus, and Gypaetus barbatus) are the most important avian species because of their sacred roles in celestial burial. A total of 27 bird species were recorded as being used as traditional medicine. The high valuation of birds in Tibetan culture has likely contributed to the transmission of traditional knowledge regarding birds as well as to the conservation of bird biodiversity in the study area. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a very common bone disease in the elderly population and can lead to fractures and disability. Malnutrition can lead to osteoporosis. The geriatric nutritional risk index (GNRI) is a tool used to assess the risk of malnutrition and complications associated with nutritional status in older patients and is a crucial predictor of many diseases. Hence, this study investigated the association between the GNRI and the presence of osteoporosis and assessed the value of this index for predicting osteoporosis in patients with type 2 diabetes mellitus (T2DM). Methods: This cross-sectional study enrolled 610 elderly patients with T2DM. General and laboratory data of the patients were collected, along with their measurements of bone mineral density (BMD). The GNRI was calculated based on ideal body weight and serum albumin (ABL) levels. Correlation analysis was performed to determine the relationship between the GNRI and BMD and bone metabolism indices. The GNRI predictive value for osteoporosis development was analyzed through logistic regression analysis and by creating a receiver operating characteristic curve (ROC), calculating the area under the curve (AUC). Results: All patients were divided into the no-nutritional risk and nutritional risk groups. Compared with the no-nutritional risk group, the nutritional risk group had a longer diabetes course, older age, higher HbA1c levels, higher prevalence of osteoporosis; lower BMI, ABL,triglyceride (TG),Calcium (Ca),25-hydroxy-vitamin-D(25(OH)D),and parathyroid hormone(PTH) and lower femoral neck BMD,total hip BMD (P < 0.05). All patients were also assigned to the non-osteoporosis and osteoporosis groups. The non-osteoporosis group had higher GNRI values than the osteoporosis group (P < 0.05). Correlation analysis revealed a positive correlation between the GNRI and lumbar BMD, femoral neck BMD, and total hip BMD (P < 0.05). After the adjustment for confounding factors, Spearman's correlation analysis revealed that the GNRI was positively correlated with Ca, 25(OH)D, and PTH and negatively correlated with alkaline phosphatase (ALP) and procollagen of type-1 N-propeptide (P1NP). Regression analysis exhibited that the GNRI was significantly associated with osteoporosis. The ROC curve analysis was performed using the GNRI as the test variable and the presence of osteoporosis as the status variable. This analysis yielded an AUC for the GNRI of 0.695 and was statistically significant (P < 0.05). Conclusions: A lower GNRI among T2DM patients in northern China is associated with a higher prevalence of osteoporosis. [ABSTRACT FROM AUTHOR]

Organic components in atmospheric fine particulate matter have attracted much attention and several scientific studies have been performed, although most of the sample extraction methods are time consuming and laborious. Accelerated solvent extraction (ASE) is a new sample extraction method offering number of advantages, such as low extraction cost, reduced solvent and time consumption, and simplified extraction protocols. In order to optimize ASE methods to determine the concentrations of organic compounds in atmospheric fine particulate matter, different parameters were set out for the experiment, and the optimal method was selected according to the recoveries of the standard (i.e., n−alkanes and polycyclic aromatic hydrocarbons (PAHs)). This study also involves a comparison of the optimal method with the traditional method of ultrasonic extraction (USE). In addition, the optimized method was applied to measure the mass concentrations of organic compounds (n−alkanes and PAHs) in fine particulate matter samples collected in Beijing. The findings showed that the average recovery of target compounds using ASE was 96%, with the majority of compounds falling within the confidence levels, and the ASE recoveries and precision were consistent with the USE method tested. Furthermore, ASE combines the advantages of high extraction efficiency, automation, and reduced solvent use. In conclusion, the optimal ASE methods can be used to extract organic components in atmospheric particulate matter and serve as a point of reference for the development of analytical methodologies for assessing organic compounds in atmospheric particulate matter in China. [ABSTRACT FROM AUTHOR]

Objective: Myocardial injury leads to higher mortality in COVID‐19, but the causes and risk factors are variable. We evaluated the potential risk factors for myocardial injury in COVID‐19 patients to improve treatment strategies and reduce mortality. Methods: This retrospective analysis enrolled 325 COVID‐19 patients in Shanghai, China. Results: The median age in our cohort was 51 [range 15‐88] years, 26 (8%) were critically ill, and 177 patients (19.7%) had myocardial injury. The myocardial injury group comprised older, more critically ill patients with hypertension, other comorbidities, history of angiotensin‐converting enzyme inhibitor/angiotensin receptor blocker use, lower peripheral blood lymphocyte count and higher D‐dimer levels. Binary logistic regression analysis identified only age was an independent risk factor for myocardial injury (odds ratio 1.019; 95% confidence interval 1.003‐1.036; age increase by 1 year = myocardial injury risk increase by 1.9%). Conclusions: Older age was associated with a higher incidence of myocardial injury for COVID‐19 patients. [ABSTRACT FROM AUTHOR]

Automatic identification system (AIS)-based ship trajectory data are important for analysing maritime activities. As the data accumulate over time, trajectory compression is needed to alleviate the pressure of data storage, migration and usage. The grating algorithm, as a vector data compression algorithm with high compression performance and low computation complexity, has been considered as a very promising approach for ship trajectory compression. This algorithm needs the threshold to be set for each trajectory which limits the applicability over a large number of different trajectories. To solve this problem, a dynamic adaptive threshold grating compression algorithm is developed. In this algorithm, the threshold for each trajectory is dynamically generated using an effective approaching strategy. The developed algorithm is tested with a complex trajectory dataset from the Qiongzhou Strait, China. In comparison with the traditional grating method, our algorithm has improved advantages in the ease of use, the applicability to different trajectories and compression performance, all of which can better support relevant applications, such as ship trajectory data storage and rapid cartographic display. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the current status of physical restraint of patients in the neurosurgical intensive care unit (NSICU) and analyze the factors influencing this measure using a cross-sectional study design. A total of 312 patients from four tertiary hospitals in NSICU were investigated in Beijing, China. The rate of physical restraint of patients in the NSICU was 42.9%. In 41.8% of cases, nurses performed physical restraint based on experience, and 45.5% of patients had physical restraint-related nursing records. Binary logistic regression analyses revealed that physical restraint was associated with delirium, mild-to-moderate disturbance of consciousness, history of extubation, surgery, and use of sedatives within 24 hour. Analysis of related factors can provide a reference for nurses and managers to improve physical restraint strategies. [ABSTRACT FROM AUTHOR]

In busy waterways, spatial-temporal discretisation, safe distance and collision avoidance timing are three of the core components of ship traffic flow modelling based on cellular automata. However, these components are difficult to determine in ship traffic simulations because the size, operation and manoeuvrability vary between ships. To solve these problems, a novel traffic flow model is proposed. Firstly, a spatial-temporal discretisation method based on the concept of a standard ship is presented. Secondly, the update rules for ships' motion are built by considering safe distance and collision avoidance timing, in which ship operation and manoeuvrability are thoroughly considered. We demonstrate the effectiveness of our model, which is implemented through simulating ship traffic flow in a waterway of the Yangtze River, China. By comparing the results with actual observed ship traffic data, our model shows that the behaviours and the characteristics of ships' motions can be represented very well, which also can be further used to reveal the mechanism that affects the efficiency and safety of ship traffic. [ABSTRACT FROM AUTHOR]

Benzene homologues are important chemical precursors to the formation of ground-level ozone and secondary organic aerosol (SOA) in the atmosphere, in addition, some toxic species are harmful to human health. Strict countermeasures have been taken to fight air pollution since 2013, and total amount control of volatile organic compounds is being promoted in China at present. Therefore, it is important to understand the pollution situation and the control status of ambient benzene homologues in China. This paper reviews research progress from published papers on pollution characteristics, atmospheric photochemical reactivity, health risk assessment and source identification of ambient benzene homologues in recent years in China, and also summarizes policies and countermeasures for the control of ambient benzene homologues and the relevant achievements. The total ambient levels of benzene, toluene, ethylbenzene and xylenes (BTEX) shows a declining tendency from 2001 to 2016 in China. The mass concentrations of BTEX are generally higher in southern regions than in northern regions, and they present vertical decreasing variation characteristics with increasing altitude within the height range of about 5500 m. Toluene has the highest ozone formation potential and SOA formation potential both in urban areas and background areas, while benzene poses an obvious carcinogenic risk to the exposed adult populations in urban areas. Source identification of ambient benzene homologues suggested that local governments should adopt differentiated control strategies for ambient benzene homologues. Several recommendations are put forward for future research and policy-making on the control of ambient benzene homologues in China. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Research progress of observation-based ozone formation sensitivity is reviewed. • Threshold values for Photochemical Indicator methods need to be localized. • Reaction mechanisms and monitoring capability need to be improved for OBM. • Ozone formation sensitivity in China presents the gradual shifting tendency. • Dynamic regulation capability for ozone pollution control needs to be built. Observation-based method for O 3 formation sensitivity research is an important tool to analyze the causes of ground-level O 3 pollution, which has broad application potentials in determining the O 3 pollution formation mechanism and developing prevention and control strategies. This paper outlined the development history of research on O 3 formation sensitivity based on observational methods, described the principle and applicability of the methodology, summarized the relative application results in China and provided recommendations on the prevention and control of O 3 pollution in China based on relevant study results, and finally pointed out the shortcomings and future development prospects in this field in China. The overview study showed that the O 3 formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO x -limited regime due to the implementation of the O 3 precursors emission reduction policies; O 3 pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O 3 pollution control measures should be improved. There are still some current deficiencies in the study field in China. Therefore, it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved; the atmospheric chemical mechanisms should be vigorously developed, and standardized methods for determining the O 3 formation sensitivity should be established in China in the near future. [Display omitted] [ABSTRACT FROM AUTHOR]

Aims and objectives To explore the incidence of delirium in cerebrovascular patients admitted in our Neurosurgery Intensive Care Unit and analyse the risk factors leading to delirium. Background Delirium is one of the most common mental disorders in general hospitals, but the incidence of different kinds of diseases and studies varies. Cerebrovascular patients in our Neurosurgery Intensive Care Unit are high-risk groups for delirium; identifying risk factors for delirium and taking early interventions are crucial for patient prognosis. Design A prospective study. Methods A convenience sampling method was used to collect data from 128 patients in the Neurosurgery Intensive Care Unit of Xuanwu Hospital, Capital Medical University, Beijing, China, between May 2016-January 2017. Researchers used Confusion Assessment Method for the Intensive Care Unit (Chinese version) to assess each patient's delirium statement twice a day at regular times. We also collected other independent data variables and followed up the short-term clinical outcomes daily. Results On the basis of Confusion Assessment Method for the Intensive Care Unit evaluation, patients were divided into a delirium group and a nondelirium group. The prevalence of delirium among the 128 patients was 42.2%. Multivariate analysis showed that severity of illness, fever, the use of physical restraints and sleep deprivation were independent predictors of delirium in cerebrovascular patients in the Neurosurgery Intensive Care Unit. Conclusions Cerebrovascular patients in the Neurosurgery Intensive Care Unit with a critical condition, fever or use of physical restraints or experiencing sleep deprivation were more prone to delirium. Relevance to clinical practice Cerebrovascular patients in the Neurosurgery Intensive Care Unit showed a high incidence of delirium. There are many risk factors leading to delirium, some of which are independent predictors of intensive care delirium. Patients with delirium will suffer various adverse effects upon their short-term clinical outcomes. Therefore, nurses should pay close attention to changes in a patient's mental state and learn about the risk factors associated with delirium, in order to be able to take early measures to prevent delirium. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chemical profiles were established using UPLC-QTof-MS metabolomics. • Over 100 marker compounds contributing to the chemotaxonomy were characterized. • All extracts inhibited NO production in LPS-induced RAW264.7 cells at 100 μ g/mL. • H. japonicum showed cytotoxicity to SMMC-7721 cells (IC 50 = 59.8 μ g/mL). • Potential antiproliferative markers were identified using a chemometrics approach. Many Hypericum species have been used as medicinal plants, herbal teas, and dietary supplements around the world. A previous ethnobotanical survey found that seven Hypericum species in southern China (H. daliense , H. hengshanense , H. himalaicum , H. japonicum , H. petiolulatum subsp. yunnanense , H. seniawinii , and H. wightianum) have been used traditionally to treat inflammation and infectious diseases, but studies on the chemical compositions and bioactivities of these folk medicines are limited. The current study aimed to characterize bioactive marker compounds correlated with two in vitro bioassays for cytotoxicity and anti-inflammation. Methanolic extracts of these species were chemically profiled using UPLC-QTof-MS metabolomics, characterizing the 52 major components from these Hypericum species. To chemically differentiate these seven species, 112 chemical features were characterized as potential chemotaxonomic markers, out of which 89 were tentatively identified. Using a chemometric approach, antiproliferative activity was tracked with chemical markers. H. japonicum showed antiproliferative effects on SMMC-7721 human hepatocarcinoma cell line with an IC 50 value of 59.8 μ g/mL. Comparison of H. japonicum to six other Hypericum species revealed that betulinic acid, isojacareubin, and taxifolin are potential antiproliferative compounds. In addition, a primary in vitro anti-inflammatory assay revealed that all the seven extracts inhibited NO production in lipopolysaccharide-induced RAW 264.7 murine macrophage cells at 100 μ g/mL, indicating that anti-inflammatory compounds may exist in all the seven species. Out of the 52 major components identified from these species, 11 have been previously reported to possess anti-inflammatory properties. These findings provide a scientific rationale for traditional uses of the seven Hypericum species in China and merit further study for the development of new medicinal products. [ABSTRACT FROM AUTHOR]

Hypericum species have been used traditionally as astringent, antipyretic, diuretic, antiphlogistic, analgesic, and antidepressant in Europe, America, Africa, and Asia. One of the most extensively investigated medicinal herbs, H. perforatum L. (St. John's wort), is widely used in many countries to treat mild to moderate mental depression. Hypericum species are abundant throughout China, including 30 used as ethnomedicines. There are limited publications describing the ethnobotanical uses and biological activities associated with Hypericum species in China. Some reported activities include the treatment of wounds and bruises, irregular menstruation, dysentery, hepatitis, mastitis, jaundice, hemoptysis, and epistaxis. This review aims to critically examine how Hypericum species are used ethnomedicinally in China, to see if the ethnobotanical data may be useful to help prioritize Hypericum species and certain phytochemical constituents that may be new drug leads, and consider the focus and lack of the phytopharmacological study on Hypericum species in China. Classic medicinal books and ethnomedicinal publications were reviewed for the genus Hypericum (called jin si tao in Chinese). In addition, relevant information about ethnobotany, phytochemistry, and pharmacology were from online databases including SciFinder, Science Direct, PubMed, Google Scholar, and China National Knowledge Infrastructure (CNKI). " Hypericum ", "金丝桃", "ethnobotany", "traditional use", "ethnomedicine", "phytochemistry", "pharmacology" and "bioactivity" were used as keywords when searching the databases. Thus, available articles from 1959 to 2019 were collected and analyzed. Among 64 Hypericum species recorded in China, 30 have been used as ethnomedicines by 15 linguistic groups such as Dai, Dong, Han, Miao, and Mongolian people. Hypericum species in China possess traditional uses which are also mirrored in Europe, America, Africa, and other countries in Asia. However, there are some unique ethnomedicinal uses in China. For example, several Hypericum species are used as a local remedy in southwest China, and H. attenuatum Fisch. ex Choisy is used to treat cardiac disorders in northeast China. Antitumor, anti-inflammatory, antimicrobial, neuroprotective, antidepressant, hepatoprotective, cardioprotective, and antiviral activities have been reported in numerous biological studies. The main phytochemical constituents in Hypericum consist of phloroglucinols, naphthodianthrones, xanthones, flavonoids, and terpenoids. There is a rich traditional knowledge regarding the ethnomedicinal uses of Hypericum species in China. Through phytochemical and pharmacological studies, several medicinal Hypericum from China have yielded many bioactive phytochemicals, possessing antitumor, anti-inflammatory, antimicrobial, and neuroprotective properties. Hypericum species from China are potential sources of drugs to fight cancer and other chronic diseases. Remarkably, nearly half of Hypericum species in China have rarely been studied, and their ethnomedicinal potential have not been scientifically evaluated. Thus, in vitro mechanistic studies, in vivo pharmacology, and clinical efficacy are all needed, prioritizing those studies that relate most closely with their traditional uses. In addition, a comprehensive plant-resource evaluation, quality control, and toxicology studies are needed. Image 1 [ABSTRACT FROM AUTHOR]

Hypericum stellatum, a species endemic to China, is used to treat hepatitis by several ethnic groups in Guizhou Province. This research was inspired by the traditional medicinal usage of H. stellatum, and aims to explore the phytochemistry and bioactivity of H. stellatum to explain why local people in Guizhou widely apply H. stellatum for liver protection. In this study, two new prenylated xanthones, hypxanthones A (8) and B (9), together with seven known compounds, were isolated from the aerial parts of the plant. Spectroscopic data as well as experimental and calculated ECD spectra were used to establish the structures of these compounds. Six xanthones isolated in this study, together with four xanthones previously isolated from H. stellatum, were evaluated for their growth-inhibitory activities against five human liver carcinoma cell lines to analyze the bioactivity and structure-activity relationship of xanthones from H. stellatum. Isojacareubin (6) showed significant cytotoxicity against five human liver carcinoma cell lines, with an IC50 value ranging from 1.41 to 11.83 μM, which was stronger than the positive control cisplatin (IC50 = 4.47–20.62 μM). Hypxanthone B (9) showed moderate cytotoxicity to three of the five cell lines. Finally, structure-activity analysis revealed that the prenyl and pyrano substituent groups of these xanthones contributed to their cytotoxicity. [ABSTRACT FROM AUTHOR]

To investigate the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts of the workers, domestic and foreign published research data on the change of human peripheral blood leukocyte counts under low-level occupational benzene exposure from January 1990 to December 2020 were collected and analyzed. According to the literature inclusion and exclusion criteria, 18 independent studies from 12 publications were selected for meta-analysis to explore the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts. The results showed that the peripheral blood leukocyte counts abnormal rates of low-level occupational benzene exposure group were higher than those of the control group, and the difference was statistically significant. Low-level occupational benzene exposure could result in a relatively higher abnormal rate of peripheral blood leukocyte counts in the exposed population, indicating that low-level occupational benzene exposure at workplaces specified by the current benzene occupational exposure limit in China would affect the peripheral blood leukocyte counts of the workers, thus benzene with concentrations under the limit in the ambient air of workplace could be still harmful to the health of the exposed workers. The results of this study could provide a scientific basis for future revision of the benzene occupational exposure limit in China, and could also be a reference for the formulation of environmental standard concerning benzene in China in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

Carbonyls have attracted continuous attention due to their critical roles in atmospheric chemistry and their potential hazards to the ecological environment and human health. In this study, atmospheric carbonyls were measured during several ground-level-ozone (O 3 ) pollution episodes at three urban sites (CRAES, IEP and BJUT) in Beijing in 2019 and 2020. Comparative analysis revealed that the carbonyl concentrations were 20.25 ± 6.91 ppb and 13.43 ± 5.13 ppb in 2019 and 2020 in Beijing, respectively, with a significant spatial trend from north to south, and carbonyl levels in urban Beijing were in an upper-intermediate range in China, and higher than those in other countries reported in the literature. A particularly noteworthy phenomenon is the consistency of carbonyl concentrations with variations in O 3 concentrations. On O 3 polluted days, the carbonyl concentrations were 1.3-1.5 times higher than those on non-O 3 polluted days. Secondary formation contributed more to formaldehyde (FA) and acetaldehyde (AA) on O 3 polluted days, while the anthropogenic emissions were more significant for acetone (AC) on non-O 3 polluted days. Vehicle exhaust and solvent utilization were the main primary contributors to carbonyls. Due to reduced anthropogenic emissions caused by the COVID-19 lockdown and the "Program for Controlling Volatile Organic Compounds in 2020" in China, the contributions of primary emissions to carbonyls decreased in 2020 in Beijing. Human cancer risks to exposed populations from FA and AA increased with elevated O 3 levels, and the risks still remained on non-O 3 polluted days. The residents around the BJUT site might experience relatively higher human cancer risks than those around the other two sites. The findings in this study confirmed that atmospheric carbonyl pollution and its potential human health hazards cannot be ignored in urban Beijing; therefore, more strict control strategies for atmospheric carbonyls are urgently needed to better protect human health in Beijing in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Surface water (SW) and groundwater (GW) are crucial water supply sources in the southern margin of Junggar Basin in Xinjiang. The sources of toxic components in SW and GW and their negative effects on human health are of great concern. A total of 40 SW and 596 GW samples were collected at the oasis belt to analyze distribution, sources and potential health risks of inorganic pollutants in SW and GW. Results revealed that SW quality was severely affected by Hg, 30.0% of which had Hg concentration greater than the national drinking water standard. High Hg SW was mainly distributed near Manas County and Urumqi City. GW quality was mostly affected by SO 4 2- , 24.7% of which had SO 4 2- concentration greater than the national drinking water standard. High SO 4 2- GW primarily occurred in the northwest and middle of the study area. Source apportionment of inorganic pollutants identified geological background, municipal wastewater disposal, water-rock interaction, geological environment, geological structure and industrial emission were the prominent potential sources of inorganic pollution in SW, with contribution rates of 1.2%, 10.0%, 43.6%, 35.1%, 6.3% and 3.8%, respectively. Five potential pollution sources in GW (including geological background, municipal wastewater disposal, water-rock interaction, geological environment and aquifer burial depth) were identified, with contribution rates of 0.7%, 9.6%, 77.6%, 11.1% and 1.0%, respectively. Probabilistic health risk assessment showed that Cl - and As in SW and GW were the main inorganic pollutants threatening human health. Non-carcinogenic risks for adults and children were negligible, while carcinogenic risks cannot be negligible. Furthermore, the contribution of potential pollution sources to health risks was quantified using positive matrix factorization coupling with health risk assessment model. Based on which, we offered the suggestion that water quality improvement in contaminated areas should be implemented in combination with pollution monitoring systems., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Polycyclic aromatic hydrocarbons (PAHs) and their nitrated derivatives (NPAHs) attract continuous attention due to their distinct carcinogenicity and mutagenicity. To investigate the characteristics, sources, formation mechanism and health risk assessment of PAHs and NPAHs, PM 2.5 were collected at an urban site in Beijing from 2017 to 2018. The highest PAHs and NPAHs concentrations were 77.92 ± 54.62 ng/m 3 and 963.71 ± 695.06 pg/m 3 in the winter campaign, which were several times larger than those in other seasonal campaigns. Distinct diurnal variations of nocturnal levels higher than daytime levels were shown for PAHs and NPAHs. Source analysis indicated that besides vehicle exhaust, biomass burning and coal combustion were important sources of PAHs and NPAHs in the fall and winter campaigns. Secondary formation in atmosphere was another source of NPAHs especially in the spring and summer campaigns. NO 2 and RH could positively influence the heterogeneous formation of NPAHs when RH was less than 60%. Quantum calculation results confirmed the formation pathway of 2N-FLA from the OH/NO 3 -initiated oxidation of FLA. The results of health risk assessment showed the potential health risks for the residents, especially in the winter campaign. These results indicated that PAHs and NPAHs still deserve attention following with the decrease concentrations of particulate matter., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Nitrated aromatic compounds (NACs) constitute a key segment of brown carbon (BrC), thereby contributing to the light-absorbing characteristics of aerosols in the atmosphere. However, until recently, there is a scarcity of research on their generation in the urban environment. The current study is based upon an extensive field study of NACs from fine particle samples obtained at an urban location in Beijing in the spring and summer of 2017, which was characterized by both high anthropogenic volatile organic compounds (VOCs) and high-NO x dominated conditions. The mean total concentration of the nine NACs was 8.58 ng m -3 in spring and 8.54 ng m -3 in summer. In the spring, the most abundant NACs were 4-nitrophenol (33.7%) and 4-nitrocatechol (19.3%), while in the summer, the most abundant NACs were 4-nitroguaiacol (34.9%) and 2, 4-dinitrophenol (23%). Atmospheric NACs were primarily produced from coal combustion (52%) and biomass burning (32%) in spring, and originated from the secondary formation (37%) and traffic (35%) in summer. NO 2 could promote the formation of NACs with a significant effect on their compositions, especially for nitrophenols and nitrocatechols. It can also affect the formation of nitrated aerosols and their existing form. Inorganic nitrates were increased to conversion in the daytime when NO 2 concentrations were higher than 30 ppb, but the corresponding oxidation products shifted to primarily organic ones at night. The transition was VOC-sensitive regimes for NAC formation, and nitration of toluene was a more important pathway during the campaign in Beijing., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Volatile halogenated hydrocarbons (VHCs) have attracted wide attention in the atmospheric chemistry field since they not only affect the ecological environment but also damage human health. In order to better understand the characteristics, sources and health risks of VHCs in typical urban areas in Beijing, and also verify the achievement in implementing the Montreal Protocol (MP) in Beijing, observational studies on 22 atmospheric VHCs species were conducted during six air pollution episodes from December 2016 to May 2017. The range in daily mixing ratios of the 6 MP-regulated VHCs was 1000-1168 pptv, and the 16 MP-unregulated VHCs was 452-2961 pptv. The 16 MP-unregulated VHCs accounted for a relatively high concentration proportion among the 22 VHCs with a mean of 70.25%. Compared with other regions, the mixing ratios of MP-regulated VHCs were in the middle concentrations. The mixing ratios of the MP-regulated VHCs remained the same concentrations during the air pollution episodes, while the concentrations of MP-unregulated VHCs were generally higher on polluted days than on clean days and increased with the aggravation of the pollution episodes. The mixing ratios of dichlorodifluoromethane and trichlorofluoromethane were higher than Northern Hemisphere (NH) background values, while the mixing ratios of the other 4 MP-regulated VHCs were moderate and similar to the NH background values. All the 9 VHCs with carcinogenic risk might pose potential carcinogenic risks to the exposed populations in the six pollution episodes, while none of the 12 VHCs might pose appreciable non-carcinogenic risks to the exposed populations. Considering the higher concentration levels and higher risk values of 1,2-dichloropropane, 1,2-dichloroethane, carbon tetrachloride and trichloromethane, Beijing needs to further strengthen the control of these VHCs. The analysis of air mass transportation and PMF model showed that regional transportation and leakage of CFCs banks were important sources of VHCs in Beijing, and the contribution of industrial process and solvent usage should not be neglected. The results revealed the effective implementation of the MP in Beijing and its surrounding areas, while further measures are suggested to control the emissions of important VHCs especially from regional transportation and leakage of CFCs banks to reduce the possible health risks to the exposed population., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The deteriorating groundwater quality due to natural genesis and anthropogenic activities has prevented the sustainable use of groundwater. The characteristics and factors affecting groundwater quality for drinking in shallow aquifers (depth ≤ 100 m) in the plain area of Yarkant River Basin in Xinjiang were analyzed using water quality index (WQI), geostatistics, and geochemical methods. Results showed that the groundwater was weak-alkaline with neutral pH, with dominant water types being SO 4 •HCO 3 -Ca•Mg, SO 4 •Cl•HCO 3 -Na•Ca, SO 4 •HCO 3 •Cl-Ca•Na, Cl•SO 4 -Na•Ca, and HCO 3 •SO 4 -Mg•Ca. WQI ranged between 31.79 and 549.37, and about 14.43%, 31.96%, 18.56%, 22.68%, and 12.37% of the all samples were excellent, good, medium, poor, and extremely poor quality, respectively. The proportion of excellent quality was the highest in single structure phreatic aquifer (SSPA, 50.00%) and good quality were the highest in multilayered structure phreatic aquifer (MSPA, 34.21%) and multilayered structure confined aquifer (MSCA, 28.89%). With the extension of the river, the groundwater quality gradually degenerated from south to north in phreatic aquifer (PA, including SSPA and MSPA). The further away from the Yarkant river, the worse the groundwater quality of PA. Furthermore, the WQI showed excellent, good, and an alternation of medium and poor quality (including extremely poor quality) from south to north in the MSCA. The groundwater quality deterioration might have been affected by the dissolution of evaporite minerals, such as halite, gypsum, and anhydrite and ion exchange process. In addition, local effects of anthropogenic activities and land usage patterns on the groundwater quality should be reckoned as well.