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The spontaneous combustion of residual coal in goaf has always been the focus of coal mine fire prevention and control work. Mastering the distribution law of coal spontaneous combustion risk area is the key to take prevention and control measures. Based on the latest research results in this field at home and abroad, this paper systematically analyzes the theoretical basis, evolution process and determination conditions of goaf spontaneous combustion hazard area identification by using the methods of literature research and theoretical analysis, and qualitatively summarizes the effectiveness and adaptability of coal spontaneous combustion fire prevention and control technology. Comprehensive analysis suggests that: the chain change and redistribution of stress-strain - porosity - air leakage intensity - gas volume fraction of the mined-out area are the fundamental reasons for the formation of the spontaneous combustion hazard area in the mined-out area, and the determination of the spontaneous combustion hazard area by dynamic parameters is more in line with the field practice; in engineering practice, nitrogen injection and plugging technology have obvious effect on reducing the width of oxidation spontaneous combustion zone.

ObjectiveTo analyze the epidemiological characteristics of rural banquet foodborne disease outbreaks in China from 2010 to 2020 and provide a reference for formulating rural banquet foodborne disease prevention and control measures.MethodsData on foodborne disease outbreaks in rural banquet reported in the China Foodborne Disease Outbreak Surveillance System from 2010 to 2020 were statistically analyzed.ResultsFrom 2010 to 2020， a total of 1 421 foodborne disease outbreaks were reported in rural banquets， with 31 078 cases， 64 deaths， a fatality rate of 0.21%， and an average of 22 cases per outbreak. The overall incidence showed an upward trend. The top five provinces in China were Yunnan Province， Jiangsu Province， Hu’nan Province， Sichuan Province and Anhui Province， with 728 reports accounting for 51.23% （728/1 421）. The time distribution was mainly concentrated in the second and third quarters of the year. According to the analysis of pathogenic factors， pathogenic microorganisms， such as Vibrio parahaemolyticus and Salmonella， had the highest number of cases. The disease factor causing the highest number of deaths was methanol， followed by aconitine plants， toadstools， and toxic wild honey. Meat （livestock meat， poultry meat） and aquatic products such as crustaceans， mollusks and fish were the main causes of foodborne diseases.ConclusionBased on the high incidence areas， high incidence seasons， main pathogenic factors and causes of foodborne diseases in rural banquets in China， effective measures were implemented， focusing on monitoring and management to successfully prevent and control the occurrence of such diseases.

The development of pore structure in coal reservoirs determines the adsorption performance of coal gas. The pore structure of three coal samples with different degrees of metamorphism, namely long-flame coal, coking coal and anthracite, was tested by low-temperature liquid nitrogen adsorption experiments. The pore structure was quantitatively characterized based on fractal theory, and the effect of the pore structure on the methane adsorption properties of coals with different degrees of metamorphism was analyzed in depth in combination with the methane isothermal adsorption experiments. The results showed that the degree of metamorphism and the pore fractal dimension D1 showed a “bathtub” variation, and a linear negative correlation with D2; while the specific surface area and pore volume of the coal sample were positively correlated with the adsorption constant a. The larger specific surface area and pore volume, the stronger the adsorption capacity of coal. With the increase of pore fractal dimension D1, the adsorption constant a presents an approximate linear growth trend. It can be seen that the less smooth the pore structure of coal, the larger the specific surface area will be, so that the ultimate methane adsorption capacity of coal will also increase.

In order to study the influence mechanism of effective stress on permeability, the coal permeability test experiment under simultaneous loading of axial and confining pressure was carried out using the self-developed coal-rock gas adsorption-desorption-seepage platform. The mean effective stress parameter is introduced to characterize the loaded state of the coal body. At the same time, in order to eliminate the influence of the individual differences of the specimens, the effective stress sensitivity coefficient is defined, and the control mechanism and variation law of the effective stress on the permeability of the coal body are discussed in depth. The results show that when the gas pressure remains constant, the coal permeability decreases gradually with the increase of the effective stress, and its variation law conforms to the negative exponential relationship. With the increase of effective stress, the sensitivity coefficient gradually decreases, and it conforms to the power function relationship. At the same time, a mathematical model of coal sample permeability and effective stress is constructed based on the sensitivity coefficient.

ObjectiveTo explore the effective prevention of wild mushroom poisoning， the years of life lost （YLLs） from wild mushroom poisoning in Yunnan Province from 2017 to 2021 was calculated .MethodsThe death data of wild mushroom poisoning in Yunnan Province were collated according to gender， age and year. The YLLs was calculated based on the World Health Organization excel calculation template， and the YLLs was compared among different age， gender and year groups. The indirect economic loss was estimated using human capital approach.ResultsThe YLLs due to wild mushroom poisoning was 2 760 person-years （5.70 person years per 100 000 population）. People aged from 30 to 59 years old were a risk group for wild mushroom poisoning with YLLs of 1 602 person-years. Children aged

The mechanism of MaiFuSheng (MFS) on inhibiting Nonalcoholic Fatty Liver Disease (NAFLD) were investigated based on the exploration of chemical compositions, the techniques of network pharmacology and molecular docking, and the validation using NAFLD mice model. The components of MFS were identified through UPLC-Zeno TOF-MS/MS. The Swiss Bioinformatics Research Platform were applied to obtain active components and potential targets of MFS. The DisGeNet and OMIM databases were used to screen disease targets of NAFLD. The intersection between disease targets and potential targets of MFS were obtained from Venn diagram, which were analyzed by constructing cross-target protein-protein interaction (PPI) network. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were conducted on Metascape database. The molecular docking about core targets and active components of MFS were carried out. Using high-fat diet (HFD)-induced C57BL/6J mice as NAFLD animal model to validate key targets. A total of 130 compounds were recognized, 54 active constituents and 176 potential targets of NAFLD were collected. The molecular docking experiments for the top 10 components with the targets are based on the degree value. We found docking models with the best binding energy for TNF-α with Quercetin, IL-17 with Asiatic acid, and IL-1β with Quercetin. We applied qPCR technique to detect above inflammation and lipid metabolism related indicators. Enrichment analysis demonstrated that MFS protects NAFLD via biological processes such as fatty acid transformation and positive regulation of lipid metabolism, as well as signaling pathways such as AGE-RAGE, HIF-1, and IL-17. Compared to the control groups, the model group's ALT, TG, and LDL-C indicators increased, whereas HDL-C indicators dropped (P<0.05) . MFS and Simvastatin treatment groups significantly reduced body weight, liver weight, and fat weight compared to the model groups (P<0.05). Higher doses resulted in significant reductions in serum levels and expression of TNF-α, IL-1β, and IL-17 (P<0.01). Compared to the control groups, the MFS treatment groups can minimize liver lipid accumulation by modulating the expression of lipid metabolism-related genes and improving hepatic fat breakdown. [ABSTRACT FROM AUTHOR]

In order to study the influence of the pore characteristics of tectonic coal and primary structural coal on the gas adsorption characteristics, we take Sanjia Coal Mine outburst hole tectonic coal and primary structure as the research object, use the combining methods of mercury injection and liquid nitrogen adsorption experiment method to study the pore structure of different structures of coal, and then combined with the Menger geometric model, we analyze different structure coal pore fractal characteristics, further elaborate the pore structure fractal characteristics of the impact of gas adsorption characteristics. The results show that: there is hysteresis loop in both primary structural coal and outburst hole tectonicl coal, and the hysteresis loop in outburst hole tectonic coal is obviously larger than that in primary structural coal. The fractal dimension of outburst hole tectonic coal are both greater than that of primary structural coal, and the porosity complexity of outburst hole tectonic coal is higher than that of primary structural coal. The porosity complexity of outburst hole tectonic coal provides good conditions for gas adsorption. The overall pore development of structural coal with outburst pores is better than that of primary structural coal, and the pore development at the stage of micropore and pore is much better than that of primary structural coal.

In order to study the influence of reverse fault on coal pore structure and gas adsorption and desorption characteristics, taking 1503 mining face of Xinchun Mine in Guizhou as the research object, the coal samples at different distances from the reverse fault are selected to carry out scanning electron microscope test and low-temperature liquid nitrogen adsorption test respectively. It is concluded that the closer the coal is to the reverse fault, the more seriously affected by the reverse fault structure, and the higher the pore volume and specific surface area of coal samples, in the region of relative pressure 0.4-0.5, there is a slight inflection point in the low-temperature liquid nitrogen adsorption regression curve, indicating that there are abundant ink bottle holes in the coal sample; by studying the gas adsorption interpretation law of coal at different distances from the reverse fault, it is concluded that the gas desorption capacity increases with the increase of equilibrium pressure. Under the same desorption equilibrium pressure, the stronger the coal structure closest to the reverse fault is transformed, the stronger the gas adsorption performance is, the greater the gas adsorption capacity and adsorption rate are, and the stronger the desorption capacity is.

The pore distribution characteristics of coal not only directly affect the gas storage and migration ability in coal seam, but also directly affect the development process of physical adsorption and chemical reaction between coal and oxygen. Therefore, in-depth study of the pore distribution characteristics of coal is conducive to the reasonable classification and evaluation of coal reservoirs, and then study and analyze the laws of gas storage and migration in coal seams and the low-temperature oxidation reaction mechanism of coal, improve the accuracy of gas content prediction and gas extraction efficiency, and describe the process of coal spontaneous combustion in detail. We have systematically summarized the current research theories and methods of pore distribution characteristics of coal through a large number of relevant literature investigations, and compared and analyzed various research theories and methods, pointed out their respective advantages and disadvantages. Finally, it is proposed that the next step can be carried out from three directions: accurate measurement of micro-pores and reasonable characterization at full scale, research on microscopic effects of coal pores, and establishment of accurate coal medium models.

To effectively treat osteoarthritis (OA), the existing inflammation must be reduced before the cartilage damage can be repaired; this cannot be achieved with a single type of extracellular vesicles (EVs). Here, a hydrogel complex with logic‐gates function is proposed that can spatiotemporally controlled release two types of EVs: interleukin 10 (IL‐10)+ EVs to promote M2 polarization of macrophage, and SRY‐box transcription factor 9 (SOX9)+ EVs to increase cartilage matrix synthesis. Following dose‐of‐action screening, the dual EVs are loaded into a matrix metalloporoteinase 13 (MMP13)‐sensitive self‐assembled peptide hydrogel (KM13E) and polyethylene glycol diacrylate/gelatin methacryloyl‐hydrogel microspheres (PGE), respectively. These materials are mixed to form a "microspheres‐in‐gel" KM13E@PGE system. In vitro, KM13E@PGE abruptly released IL‐10+ EVs after 3 days and slowly released SOX9+ EVs for more than 30 days. In vivo, KM13E@PGE increased the CD206+ M2 macrophage proportion in the synovial tissue and decreased the tumor necrosis factor‐α and IL‐1β levels. The aggrecan and SOX9 expressions in the cartilage tissues are significantly elevated following inflammation subsidence. This performance is not achieved using anti‐inflammatory or cartilage repair therapy alone. The present study provides an injectable, integrated delivery system with spatiotemporal control release of dual EVs, and may inspire logic‐gates strategies for OA treatment. [ABSTRACT FROM AUTHOR]