Activin A inhibits the migration of human lung adenocarcinoma A549 cells induced by EGF.

Activin A, a member of the transforming growth factor ß (TGF-ß) superfamily, is involved in tumorigenesis and tumor progression. However, it remains unclear whether activin A can affect the migration of lung adenocarcinoma (LUAD) cells. In this study, the results of differentially expressed genes (DEGs) identification revealed that lung adenocarcinoma tissues exhibited lower expression of activin ßA mRNA, but higher expression of epidermal growth factor (EGF) and MMP9 mRNA compared to nontumor tissues. Moreover, we found that activin A inhibited human LUAD A549 cell proliferation promoted by EGF. Additionally, EGF induced A549 cell migration in microfluidic device, while activin A attenuated EGF actions. Simultaneously, EGF increased the levels of migration-related proteins, but activin A played the opposite role. Furthermore, the study revealed that EGF upregulated the ratio of p-ERK/ERK in A549 cells, which was weakened by activin A, and A549 cell migration regulated by activin A was not related to calcium signaling. In addition, the inhibitory effect of activin A on EGF-induced A549 cell migration was attenuated by the ERK inhibitor FR180204. These findings demonstrate that activin A effectively hinders the migration of A549 cells induced by EGF through ERK1/2 signaling, suggesting that targeting activin A may hold promise in the treatment of EGF-dependent LUAD growth and metastasis.

Feasibility analysis of using short-term rainfall time series to evaluate rainwater harvesting systems considering climate change.

Employing recent short-term historical rainfall data may enhance the performance of rainwater harvesting systems (RWHs) in response to climate change. However, this assumption lacks extensive research, and the evaluation of RWHs currently relies on long-term historical rainfall time series. This study evaluates the feasibility of this assumption and aims to identify the optimal rainfall time series for evaluating RWH performance under climate change. We evaluated RWHs in residential buildings across 16 Japanese cities utilizing historical rainfall time series of varying lengths and 30-year predicted rainfall time series. The minimum rainfall time series length was obtained based on the similarity index between the evaluation results for historical and future periods. The corresponding optimal series can be determined from the distribution of similarity indices in the minimum length. Finally, we introduce supply pressure indices (SPIs) to summarize the rainfall characteristics of these optimal rainfall time series. Our findings highlight that the minimum rainfall time series length increased from 1 year to 30 years as building non-potable water demand rose and city locations varied. Utilizing rainfall time series incorporating recent rainfall data yielded more dependable evaluation results for RWHs under climate change. These optimal rainfall time series share common characteristics with SPIs ranging from 5.37 to 17.87 mm/d, contingent on the local rainfall patterns. Our study concludes that utilizing recent short-term historical rainfall data is feasible to evaluate and design RWHs under climate change.

Mid-Pleistocene climate transition triggered by Antarctic Ice Sheet growth.

Despite extensive investigation, the nature and causes of the Mid-Pleistocene Transition remain enigmatic. In this work, we assess its linkage to asynchronous development of bipolar ice sheets by synthesizing Pleistocene mid- to high-latitude proxy records linked to hemispheric ice sheet evolution. Our results indicate substantial growth of the Antarctic Ice Sheets (AISs) at 2.0 to 1.25 million years ago, preceding the rapid expansion of Northern Hemisphere Ice Sheets after ~1.25 million years ago. Proxy-model comparisons suggest that AIS and associated Southern Ocean sea ice expansion can induce northern high-latitude cooling and enhanced moisture transport to the Northern Hemisphere, thus triggering the Mid-Pleistocene Transition. The dynamic processes involved are crucial for assessing modern global warming that is already inducing asynchronous bipolar melting of ice sheets.

Enzymatic Deacidification and Aroma Characteristics Analysis of Rapeseed Oil Using Self-Made Immobilized Lipase CALB@MCM-41-C8.

Rapeseed oil is a widely consumed edible oil that contains varieties of beneficial micronutrients such as tocopherols and phytosterols; however, the high acid value due to increased free fatty acid can imperil the oil quality and safety. This paper proposed the enzymatic deacidification for high-acid rapeseed oil and simultaneous production of functional diacylglycerols (DAGs) catalyzed by self-made immobilized lipase CALB@MCM-41-C8. The results indicate that the carrier of molecular sieve MCM-41 exhibited a sufficient surface area of 1439.9 m2/g and a proper pore size of 3.5 nm, promoting the immobilization of lipase CLAB. Under the optimal reaction conditions, the acid value of rapeseed oil was largely decreased from 15.3 mg KOH/g to 1.7 mg KOH/g within 3 h, while DAG content was increased from 1.2% to 40.2%. The antioxidant stability of rapeseed oil was also increased from 4.3 h to 7.6 h after enzymatic deacidification. Besides, the deacidified rapeseed oil exhibited fatty, bitter almond aromas, compared to the picked-vegetable, spicy, and pungent aromas for high-acid oil. Finally, the catalytic stability and applicability of CALB@MCM-41-C8 was validated, thus demonstrating the great potential of CALB@MCM-41-C8 in green refining of edible oils and sustainable synthesis of functional lipids.

Variations and driving factors for concentrations and carbon isotopes of dissolved CO2 in lake water across different Chinese lakes.

Carbon dioxide (CO2) stands as the primary driver of Earth's greenhouse effect, and it's suggested that the global contribution of CO2 emissions from lakes cannot be ignored. Despite the numerous estimations of CO2 fluxes from lakes, limited focus has been directed towards the carbon isotopes (δ13C) of dissolved CO2 in lake water. Particularly, the potential use of δ13C values in tracing the CO2 concentrations in lake water remains as an understudied area, warranting further exploration and investigation. In this study, we conducted an analysis of the concentrations and δ13C values of dissolved CO2 in 33 lakes located at the Tibetan Plateau, Chinese Loess Plateau, and Yangtze Plain (among which high-resolution spatial investigations were performed in 6 lakes through in-situ continuous monitoring). Our findings revealed spatial variations in both the CO2 concentrations and δ13C values in lakes. Additionally, notable differences are observed among lakes in different regions of China, with lakes in the Yangtze Plain exhibiting considerably higher CO2 concentrations, and the overall CO2 δ13C values in lakes on the Tibetan Plateau tend to be more positive, while those in lakes on the Chinese Loess Plateau tend to be more negative. The pH values, dissolved oxygen, and dissolved organic carbon are likely crucial factors influencing the CO2 concentrations and δ13C values in the lakes. Furthermore, lake water CO2 concentrations are negatively correlated with δ13C values of CO2 and dissolved inorganic carbon (DIC) both within a single lake with high spatial resolutions or in lake groups across different regions. These results highlight that the CO2/DIC δ13C values can be applied to trace the concentration variations of dissolved CO2 in lakes.

Microfluidic device reveals new insights into impairment of neutrophil transmigration in patients with sepsis.

Neutrophils need to migrate through tight tissue spaces to eliminate pathogens, but their movement is often hindered by their large and stiff nuclei. Neutrophil migration is impaired in sepsis patients, but it is unclear whether this defect is related to the deformability of their nuclei. Herein, we designed microfluidic devices with micron-scale narrow slits to simulate biological barriers. This setup allowed us to observe and record neutrophil movement and nuclear deformation in real-time. We also developed a method for morphological analysis to quantify nucleus deformation in numerous individual cells. Our studies showed that neutrophils from healthy individuals could adjust their nuclear shape to squeeze through these constrictions, whereas those from sepsis patients demonstrated less flexibility. Neutrophils with rigid nuclei struggled to pass through narrow gaps and were more likely to rupture under pressure. These findings suggest that the migration defects of neutrophils observed in sepsis may be attributed to the inability of neutrophils to deform their nuclei, highlighting the crucial role of microfluidic technologies in offering new insights into migration defects under pathological conditions.

Influence of eye-related behavior on myopia among junior middle school students under the background of double reduction during the COVID-19 pandemic.

BACKGROUND: To investigate the changes in the unhealthy eye-related behaviors of junior middle school students during the COVID-19 pandemic and the double reduction policy and its relationship with myopia. METHODS: Data were obtained from the 2019-2022 Tianjin Children and Youth Myopia, Common Diseases and Health Influencing Factors Survey. Latent profile analysis (LPA) and a generalized linear model (GLM) were applied to analyze the effect of eye-related behavior classes on myopia. RESULTS: A total of 2508 junior middle school students were included. The types of eye-related behavior were categorized into the medium-healthy behavior group, heavy academic burden and near-eye behavior group, insufficient lighting group and high-healthy behavior group. Students with heavy academic burdens and near-eye behavior were more likely to develop myopia than were those in the high-healthy group (OR = 1.466, 95% CI = 1.203-1.787; P < 0.001). CONCLUSIONS: The dual reduction policy has a positive effect on improving unhealthy eye-related behaviors, and the prevention and control of myopia through the use of different combinations of eye-related behaviors are heterogeneous among junior middle school students. In the post-COVID-19 period, we should continue to implement a double reduction policy and formulate targeted eye-related behavior strategies to provide an important reference for the prevention and control of myopia among children and adolescents during public health emergencies in the future.

Effects of physical activity patterns on myopia among children and adolescents: A latent class analysis.

BACKGROUND: The daily physical activity (PA) patterns of children and adolescents are intricate and ambiguous, with varying effects on myopia resulting from different combinations of PA. This study aims to scrutinize the spectrum of PA patterns among children and adolescents and assess their impact on myopia. METHODS: Data sourced from the 2014 National Student Physical Fitness Survey (Tianjin segment) encompassed PA records and visual acuity measurements of participants. Latent Class Analysis and a generalized linear model were employed to investigate the relationship between PA categories and visual acuity across different educational stages. RESULTS: The study comprised 6465 primary and middle school students, among whom 50.13% were male. PA patterns were categorized into high (27.16%), medium (29.88%) and low visual acuity regulation groups (13.97%) and the nonmainstream group (28.99%). Following adjustments for sex, age, region and BMI, the medium visual acuity regulation group exhibited a lower risk of myopia (OR = 0.617, 95% CI = 0.424-0.897, p = 0.012; OR = 0.654, 95% CI = 0.438-0.976, p = 0.038) compared to the nonmainstream group among junior and senior middle school students. CONCLUSION: The efficacy of diverse PA patterns in mitigating myopia risk varies across educational stages and is influenced by sex-specific factors. It is imperative to advance myopia management strategies by emphasizing tailored PA interventions, discerning between PA patterns and delivering timely guidance and interventions tailored to distinct educational stages and sexes.

Salinity decreases methane concentrations in Chinese lakes.

Lakes are important sources of methane (CH4), and understanding the influence of environmental factors on CH4 concentration in lake water is crucial for accurately assessing CH4 emission from lakes. In this study, we investigated CH4 concentration in two connected Tibetan Plateau lakes, Lake Keluke (an open freshwater lake) and Lake Tuosu (a closed saline lake), through in-situ continuous measurements taken in different months from 2021 to 2023. The results show substantial spatial and seasonal variations in CH4 concentrations in the two lakes, while the CH4 concentrations in Lake Keluke are consistently higher than those in Lake Tuosu for each month. Despite sharing similar environmental conditions due to connected (e.g. pH, water temperature, dissolved oxygen content, and total organic carbon content), the critical difference between the two lakes is their salinity. This implies that salinity is the critical factor contributing to the decrease in CH4 concentrations in Lake Tuosu, possibly due to the changes in microbial species between freshwater and brackish/saline lakes. Additionally, to further validate the effect of salinity on CH4 concentrations in lake water, we compared the CH4 concentrations of 33 lakes (including 5 saline lakes and 28 freshwater lakes) from the Tibetan Plateau, Chinese Loess Plateau, and Yangtze Plain, and found that saline lakes consistently exhibit lower CH4 concentrations (avg. 0.08 µmol/L), while freshwater lakes generally display higher CH4 concentrations (avg. 1.25 µmol/L) with considerable fluctuations. Consequently, freshwater and saline lakes exhibit distinct CH4 emissions, which could be used for more accurate estimation of global CH4 emission from lakes.

Activin A, a Novel Chemokine, Induces Mouse NK Cell Migration via AKT and Calcium Signaling.

Natural killer (NK) cells can migrate quickly to the tumor site to exert cytotoxic effects on tumors, and some chemokines, including CXCL8, CXCL10 or and CXCL12, can regulate the migration of NK cells. Activin A, a member of the transforming growth factor ß (TGF-ß) superfamily, is highly expressed in tumor tissues and involved in tumor development and immune cell activation. In this study, we focus on the effects of activin A on NK cell migration. In vitro, activin A induced NK cell migration and invasion, promoted cell polarization and inhibited cell adhesion. Moreover, activin A increased Ca2+, p-SMAD3 and p-AKT levels in NK cells. An AKT inhibitor and Ca2+ chelator partially blocked activin A-induced NK cell migration. In vivo, exogenous activin A increased tumor-infiltrating NK cells in NS-1 cell solid tumors and inhibited tumor growth, and blocking endogenous activin A with anti-activin A antibody reduced tumor-infiltrating NK cells in 4T-1 cell solid tumors. These results suggest that activin A induces NK cell migration through AKT signaling and calcium signaling and may enhance the antitumor effect of NK cells by increasing tumor-infiltrating NK cells.

Cenozoic Indo-Pacific warm pool controlled by both atmospheric CO2 and paleogeography.

The Indo-Pacific warm pool (IPWP) is crucial for regional and global climates. However, the development of the IPWP and its effect on the regional climate during the Cenozoic remain unclear. Here, using a compilation of sea surface temperature (SST) records (mainly since the middle Miocene) and multimodel paleoclimate simulations, our results indicated that the extent, intensity and warmest temperature position of the IPWP changed markedly during the Cenozoic. Specifically, its extent decreased, its intensity weakened, and its warmest temperature position shifted from the Indian to western Pacific Ocean over time. The atmospheric CO2 dominated its extent and intensity, while paleogeography, by restricting the distribution of the Indian Ocean and the width of the tropical seaways, controlled the shift in its warmest temperature position. In particular, the eastward shift to the western Pacific Ocean from the middle to late Miocene inferred from compiled SST records likely resulted from the constriction of tropical seaways. Furthermore, by changing the atmospheric thermal structure and atmospheric circulation, the reduced extent and intensity of the IPWP decreased the annual precipitation in the western Indian Ocean, eastern Asia and Australia, while the shift in the warmest temperature position from the Indian to western Pacific Ocean promoted aridification in Australia. Qualitative model-data agreements are obtained for both the IPWP SST and regional climate. From the perspective of past warm climates with high concentrations of atmospheric CO2, the expansion and strengthening of the IPWP will occur in a warmer future and favor excessive precipitation in eastern Asia and Australia.

Modifying effects of green space on the relationships between air pollution and ischemic cerebrovascular event recurrence in Tianjin, China.

This study aimed to explore how air pollution and green space influence ICE recurrence and whether they might interact with each other. A case-cross design was used in this study, which was carried out in Tianjin, China. A total of 8306 patients with recurrent ICE were collected from 2019 to 2020. The maximum effects of PM2.5, PM10, SO2, NO2, CO were 1.012 (95%CI: 1.004, 1.019), 1.010 (95%CI: 1.004, 1.016), 1.035 (95%CI: 0.982, 1.091), 1.067 (95%CI: 1.043, 1.091) and 1.012 (95%CI: 1.004, 1.021) , respectively, and the risk was higher in males and in the 50-60 age group. In the stratification of greening, it was found that air pollution except O3 had the highest risk of ICE recurrence for those with lower green space. Our study found that air pollution (except O3) can increase the risk of ICE recurrence, and this risk can be reduced by increasing green space.

Spatial patterns of Holocene temperature changes over mid-latitude Eurasia.

The Holocene temperature conundrum, the discrepancy between proxy-based Holocene global cooling and simulated global annual warming trends, remains controversial. Meanwhile, reconstructions and simulations show inconsistent spatial patterns of terrestrial temperature changes. Here we report Holocene alkenone records to address spatial patterns over mid-latitude Eurasia. In contrast with long-term cooling trends in warm season temperatures in northeastern China, records from southwestern Siberia are characterized by colder conditions before ~6,000 years ago, thus long-term warming trends. Together with existing records from surrounding regions, we infer that colder airmass might have prevailed in the interior of mid-latitude Eurasian continent during the early to mid-Holocene, perhaps associated with atmospheric response to remnant ice sheets. Our results challenge the proposed seasonality bias in proxies and modeled spatial patterns in study region, highlighting that spatial patterns of Holocene temperature changes should be re-considered in record integrations and model simulations, with important implications for terrestrial hydroclimate changes.

Current status of regional school health work in Tianjin during 2019-2023 / 中国学校卫生

Objective@#To explore the current status and progress of regional school health work to provide policy reference for school health improvement.@*Methods@#Survey data on school health work in Tianjin from 2019, 2021 and 2023 was used. School health staff allocation and expenditure of the health administrative department, CDC and education department, as well as the annual implementation of health education, prevention and control of common diseases and infectious diseases, sports activities and food nutrition in primary and secondary schools were analyzed. Statistical analysis was conducted using KruskalWallis test, Chisquare test, and Fishers exact test.@*Results@#The number of school health staff in the health commissions and education departments from 2019, 2021 and 2023 was relatively stable. Parttime staffs were often employed by health commissions while fulltime staffs were mainly employed by education departments. The number of school health staff at CDCs increased gradually (H=12.65, P<0.01). School health expenditure of administrative departments and schools in 2021 and 2023 increased significantly compared with that in 2019 (H=22.28, 23.75, P<0.05). More than 95% of schools set up clinics or health care rooms, and about 97% of schools had school health technicians or health teachers. More than 90% of schools had health education courses over 4 hours per semester. The rate of mental health education increased by year (86.87%, 89.91%, 96.30%, Z=2.40，P<0.05). Lack of courses regarded safety emergency and risk avoidance, growth and development, and adolescent health education. The provision rate of psychological counseling services (89.00%, 97.25%, 100.00%) and psychological problem prevention and control (56.12%, 71.56%, 81.48%) also increased by year (Z=3.83, 3.96, P<0.01). The implementation rates of prevention and control of poor vision, dental caries, overweight and obesity were all higher than 80%, and the prevention and control rate of abnormal spinal curvature showed an increasing trend (38.78%, 77.06%, 72.22%, Z=4.87, P<0.01). More than 90% of schools met the standard for physical education class hours, and the proportion of schools conducting at least 30 minutes of recess physical activities every day increased year by year (65.00%, 80.73%, 85.98%, Z=3.59, P<0.01). All schools did not have shops.@*Conclusions@#School health work in Tianjin is effective and constantly developing. It is necessary to continue to increase the investment of human resources and expenditure in school health, explore the approaches of cooccurrence and prevention of common diseases, and improve the school sports and nutrition environment.

Comorbidity of myopia and scoliosis in primary and secondary school students and analysis of risk factors in school environment in Tianjin / 中国学校卫生

Objective@#To investigate the comorbidity of myopia and scoliosis among primary and secondary school students in Tianjin, and to analyze the school environment risk factors contributing to these health issues, so as to provide a scientific basis for development effective prevention measures.@*Methods@#A total of 41 654 primary and secondary school students from 16 districts of Tianjin were selected by stratified random cluster sampling from September to October 2023 to screen for myopia and scoliosis. Univariate analysis was performed to examine the data, followed by a bivariate multivariate Logistic regression model and cumulative effect analysis to explore the influencing factors of their comorbidity.@*Results@#In 2023, the prevalence of comorbidity of screening positive myopia and scoliosis among primary and secondary school students in Tianjin was 2.65%. The prevalence was higher in suburban areas (3.26%) compared to urban areas (2.02%), higher among females (3.81%) compared to males (1.59%), and highest in high school students (6.17%) compared to middle school (4.19%) and primary school students (0.44%) (χ2=62.23, 198.69, 953.19, P<0.01). Logistic regression analysis showed that the number of physical education classes ≥3 per week, the number of eye health exercises at school ≥2 per day, outdoor activities between classes, teachers reminding to pay attention to reading and writing posture and strict eye standing posture were negatively correlated with the comorbidity of screening positive myopia and scoliosis (OR=0.66, 0.77, 0.71, 0.78, 0.74, P<0.05). Reading or electronic screen while lying or lying on the stomach was positively associated with the comorbidity of screening positive myopia and scoliosis (OR=1.77, P<0.05). Cumulative effect analysis showed that the cumulative score (4-7, 7-9, ≥10) was negatively correlated with the comorbidity of screening positive of myopia and scoliosis (OR=0.65, 0.55, 0.52, P<0.05).@*Conclusions@#The school environment support and students personal behavior habits in school are related to the comorbidity of comorbidity of screening positive myopia and scoliosis. Prevention and control of myopia and scoliosis should improve the environmental factors related to students health in school.

Activin A induces apoptosis of human lung adenocarcinoma A549 cells through endoplasmic reticulum stress pathway.

Activin A, a member of the transforming growth factor­ß (TGF­ß) superfamily, has been implicated in the tumorigenesis and progression of various cancers. However, it remains unclear whether activin A induces apoptosis in human lung adenocarcinoma cells through the endoplasmic reticulum (ER) stress pathway. In the present study, BrdU, flow cytometry and western blotting were used to examine cell proliferation, apoptosis and protein expression, respectively. The present study revealed that activin A inhibited human lung adenocarcinoma A549 cell proliferation, induced apoptosis, and upregulated the protein levels of C/EBP homologous protein (CHOP), growth arrest and DNA damage­inducible protein 34 (GADD34), cleaved­caspase­3 and caspase­12. Furthermore, the administration of activin A did not alter the levels of suppressor of mothers against decapentaplegic 3 (Smad3) or phosphorylated (p)­Smad3 proteins, whereas, it significantly elevated the levels of ActRIIA and p­extracellular signal regulated kinase proteins 1 and 2 (ERK1/2) proteins in A549 cells. The apoptotic effects of activin A on A549 cells were attenuated by the ERK inhibitor FR180204, which also downregulated CHOP and caspase­12 protein levels. Additionally, activin A increased intracellular calcium flux in A549 cells, and the calcium ion chelator BAPTA acetoxymethyl ester (BAPTA­AM) inhibited activin A­induced A549 cell apoptosis, whereas the calcium agonist ionomycin significantly increased apoptosis of A549 cells induced by activin A. These findings indicated that the activation of the ER stress pathway resulting in apoptosis of A549 cells triggered by activin A is facilitated by the ActRIIA­ERK1/2 signaling and calcium signaling. The present findings suggest that the agonists of ERK and calcium signaling exhibit promising clinical therapeutic potential for the induction of apoptosis in lung adenocarcinoma.

Unraveling FOXO3a and USP18 Functions in Idiopathic Pulmonary Fibrosis through Single-Cell RNA Sequencing of Mouse and Human Lungs.

Background Idiopathic pulmonary fibrosis (IPF) is identified as a chronic, progressive lung disease, predominantly marked by enhanced fibroblast proliferation and excessive deposition of extracellular matrix. The intricate interactions between diverse molecular pathways in fibroblasts play a crucial role in driving the pathogenesis of IPF. Methods This research is focused on elucidating the roles of FOXO3a, a transcription factor, and USP18, a ubiquitin-specific protease, in modulating fibroblast functionality in the context of IPF. FOXO3a is well-known for its regulatory effects on cellular responses, including apoptosis and oxidative stress, while USP18 is generally associated with protein deubiquitination. Results Our findings highlight that FOXO3a acts as a critical regulator in controlling fibroblast activation and differentiation, illustrating its vital role in the pathology of IPF. Conversely, USP18 seems to promote fibroblast proliferation and imparts resistance to apoptosis, thereby contributing to the exacerbation of fibrotic processes. The synergistic dysregulation of both FOXO3a and USP18 in fibroblasts was found to significantly contribute to the fibrotic alterations characteristic of IPF. Conclusion Deciphering the complex molecular interactions between FOXO3a and USP18 in fibroblasts provides a deeper understanding of IPF pathogenesis and unveils novel therapeutic avenues, offering a promising potential for not just halting but potentially reversing the progression of this debilitating disease.

Source apportionment of heavy metals in PM2.5 samples and effects of heavy metals on hypertension among schoolchildren in Tianjin.

The prevalence of hypertension in children has increased significantly in recent years in China. The aim of this study was to provide scientific support to control ambient heavy metals (HMs) pollution and prevent childhood hypertension. In this study, ambient HMs in PM2.5 were collected, and 1339 students from Tianjin were randomly selected. Positive matrix factorization (PMF) was used to identify and determine the sources of HMs pollution. The generalized linear model, Bayesian kernel machine regression (BKMR) and the quantile g-computation method were used to analyze the relationships between exposure to HMs and the risk of childhood hypertension. The results showed that HMs in PM2.5 mainly came from four sources: soil dust, coal combustion, incineration of municipal waste and the metallurgical industry. The positive relationships between As, Se and Pb exposures and childhood hypertension risk were found. Coal combustion and incineration of municipal waste were important sources of HMs in the occurrence of childhood hypertension. Based on these accomplishments, this study could provide guidelines for the government and individuals to alleviate the damaging effects of HMs in PM2.5. The government must implement policies to control prime sources of HMs pollution.

iEarth: an interdisciplinary framework in the era of big data and AI for sustainable development.

The Intelligent Earth (iEarth) framework, composed of four major themes: iEarth data, science, analytics, and decision, is proposed to define and build an interdisciplinary and synergistic framework for research, practice, and education that simultaneously safeguards the sustainable development of our living planet.

Study on the mesh size determination method of blast wave numerical simulation with strong applicability.

With the rapid development of computer hardware and software technology, numerical simulations have become one of the most important tools for studying propagation law of blast wave. Results of numerical simulations of explosion events greatly depend on the mesh size. The mesh size determination methods in the literature are relatively weak in generality. In this paper, a mesh size determination method with strong applicability is proposed. According to this method, the mesh size is the product of the scale coefficient and the third root of the equivalent TNT mass. The scale coefficient is related to the model dimension, scaled distance and simulation accuracy, and is independent of the TNT shape and the location of the detonation point. A large number of numerical simulation results confirm the accuracy of this method. The recommended scale coefficient to meet the engineering accuracy requirements is related to the model dimension and scaled distance. In general, when the scaled distance and model dimension are larger, the recommended scale coefficient will be larger. In this paper, the figures and tables of the recommended scale coefficients of 1D, 2D and 3D models varying with the scaled distance are given, and their rationality is verified by the existing numerical simulation events of blast wave. They can be used as a reference to determine the mesh size in numerical simulation of blast wave.