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Reservoir spaces, such as vesicles, 'secondary' amygdales, dissolution caverns and geodes, are widely developed in the Emeishan basaltic lavas in the Zhoudaping section, Leshan, west Sichuan, China. The dissolution characteristics, cementation sequences, hydrothermal activity stages, as well as fluid types, and their effects on the reservoir capacity were investigated for each stage. Macroscopically, the dissolution features present as irregular dissolution zones, which are characterised by a light red colour. Microscopically, in the dissolved zone, the cementation-filling minerals are associated with complex fill sequences, such as quartz/laumontite/chlorite–chlorite/saponite–epidote/celadonite–cryptocrystalline chlorite–laumontite/calcite/quartz. The U–Pb geochronology shows that the age of chlorite fill in amygdales is 235.3 ± 19.6 Ma; the coarse-crystalline quartz inside dissolution caverns/geodes, 124.47 ± 5.63 to 123.84 ± 5.63 Ma; and the siliceous mineral-filled amygdales, 118.34 ± 3.70 to 114.08 ± 3.76 Ma, which correspond to the early Late Triassic and the mid–late Early Cretaceous, respectively. Combined with geochemical characteristics of post-dissolution fill, the amygdales are affected by two stages of hydrothermal activity: chlorite filling of the amygdales corresponds to post-magma hydrothermal fluids during the early Late Triassic, and the siliceous mineral-fill in amygdales corresponds to deep-sourced hydrothermal fluids during the mid–late Early Cretaceous. The geodes/dissolution caverns result from a single stage of hydrothermal activity related to the mid–late Early Cretaceous deep-source low-temperature hydrothermal fluid. The Late Triassic post-magma hydrothermal fluids are generally destructive to pores, and tectonic-related dissolution of deep-sourced hydrothermal fluids has a positive effect on the formation of reservoir spaces, greatly enhancing fluid storage and flow capacities of the volcanic lavas. We recommend the multi-stage hydrothermal dissolution during Late Triassic–Early Cretaceous and faults, fractures and columnar joints be the focus of hydrocarbon exploration. The reservoir spaces developed in the Zhoudaping section, such as amygdales, dissolution caverns and geodes, were controlled by different stages and types of hydrothermal alteration. Amygdales are the product of two hydrothermal events, which correspond to post-magma hydrothermal fluids during the early Late Triassic and the deep-sourced hydrothermal fluids of the mid–late Early Cretaceous. Geodes/dissolution caverns are affected by deep-source low-temperature hydrothermal fluids in the mid–late Early Cretaceous. The multi-stage hydrothermal dissolution during the Late Triassic–Early Cretaceous and faults, fractures and columnar joints should be the focus of hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

The environmental behavior of arsenic (As) in soil is closely related to the composition of the soil microbial community and soil enzyme activity. In this paper, the effects of inorganic selenium (Se(IV), Se(VI)) and organic Se (Se-Cys, Se-Met) on enzyme activity and microbial community composition in As-contaminated soil were studied by a pot experiment under greenhouse conditions. The results showed that the application of inorganic Se and organic Se can significantly affect the activities of urease, catalase, invertase, fluorescein diacetate (FDA) hydrolase and dehydrogenase in As-contaminated soil. The total phospholipid fatty acid (PLFA) microbial content in the soil with organic Se treatments was higher than that in the control group (CK), while the inorganic Se treatments was opposite. Organic Se promoted the growth of microorganisms in the soil, while the inorganic Se treatments was opposite. From the perspective of the distribution and community structure of microorganisms, organic Se treatment enriches the microbial diversity and increases the content of gram-positive bacteria (G+), gram-negative bacteria (G-), and fungi, while the inorganic Se treatment group shows the opposite trend. This study can provide a reference for in-depth exploration of the mechanism of Se and microbial metabolism of As and its application in the treatment of As pollution. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Acute respiratory distress syndrome (ARDS) is greatly threatening human health with high morbidity and mortality. The pathogenesis of ARDS is closely related to the inflammatory response in patients. The micro-ribonucleic acid (miR)-155/nuclear factor-κB (NF-κB) signaling pathway is crucial in regulating the expression of inflammation-related genes. Therefore, the influences of miR-155/NF-κB signaling pathway on inflammatory factors in ARDS in neonatal pigs were explored in this study. MATERIALS AND METHODS: The model of ARDS in neonatal pigs was established first. The expression levels of miR-155, NF-κB-related proteins, and inflammatory factors in model group and control group were detected, and their differences were compared. Moreover, after treatment with the miR-155/NF-κB signaling pathway inhibitor, the changes of the inflammatory factors expression in ARDS neonatal pigs were observed at different time points. RESULTS: In the model group, the levels of miR-155 and NF-κB-related proteins were significantly increased, and the levels of inflammatory factors, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, were also increased synchronously. However, the levels of IL-4 and IL-10 declined significantly. In addition, it was proved that after treatment with the inhibitor in model group the mRNA expressions of miR-155/NF-κB signaling pathway-related proteins were significantly inhibited, and the levels of IL-1β, TNF-α, and IL-6 were also significantly inhibited (p<0.05). The levels of IL-4 and IL-10 remarkably rose after treatment with the inhibitor for 24 h (p<0.05). CONCLUSIONS: The miR-155/NF-κB signaling pathway influenced the changes of inflammatory factors in ARDS in neonatal pigs, which might be a potential target for eliminating the inflammatory response after ARDS in neonatal pigs. [ABSTRACT FROM AUTHOR]