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Straw returning has been broadly recognized as an agronomic strategy to manage soil quality and has great potential to enhance soil fertility. However, soil microbial metabolism and ecosystem multifunctionality in response to various straw returning strategies in the black soil remain poorly understood. Here, a 5‐year field trial was conducted to discover the effects of four straw management strategies (SIDP, straw incorporation by deep ploughing; SIRT, straw incorporation by rotary tillage; SM, straw mulching with no‐tillage; SR, straw removal with no‐tillage) on the soil biochemical properties in the topsoil (0–20 cm) and subsoil (20–40 cm). SM maintained soil fertility, as evidenced by increases in soil organic carbon, total nitrogen, dissolved organic carbon, and nitrogen, compared with SIDP and SR. Additionally, this strategy promoted microbial biomass. It also stimulated nutrient cycling through increased enzyme activity. Meanwhile, SM alleviated microbial carbon limitation and promoted the shift of soil microbial metabolism from P limitation to N limitation compared to other treatments, especially in the subsoil. This shift was directly influenced by soil available nutrients and microbial properties, as revealed by the partial least‐squares path modeling analysis. Besides, SM promoted soil ecosystem multifunctionality by 29%–37% in both soil layers compared to SIDP and SR. Random forest analysis indicated that soil microbial biomass and activity were the main drivers of this increase in multifunctionality. In conclusion, straw returning with no‐tillage is an optimal straw management strategy for improving the soil biochemical properties, stimulating enzyme activities, alleviating microbial carbon limitation, and increasing ecosystem multifunctionality in the Northeast Plain. [ABSTRACT FROM AUTHOR]

The HTV silicone rubber was prepared with methyl vinyl silicone rubber as the binder, fumed silica as the reinforcing filler, aluminium hydroxide as the flame-retardant filler, hydroxyl silicone oil as the structural controlled agent, and silane as the coupling agent and vulcanizing agent. The effects of the types and amounts of silane coupling agents on the mechanical properties, vulcanization characteristics, and processing properties of silicone rubber were studied. The results show that the silane coupling agent can significantly increase the tensile strength and hardness of the rubber compound, reduce the elongation at break, vulcanization rate, and roll operability, and produce certain odor. The vinyl silane coupling agents increased the MH value of the rubber. As the mount of silane coupling agent increased, the tensile strength first increased and then decreased, and the vulcanization rate decreased gradually as well as the operability of the roller and the rubber produced certain odor. Thus 2 phr of KH 560 silane coupling agent is recommended. [ABSTRACT FROM AUTHOR]

In this work, a selective and highly sensitive gas sensor using tungsten oxide (WO3) nanofibers was fabricated via electrospinning. WO3 was functionalized with gold nanoparticles by magnetron sputtering at different sputtering times to obtain Au films with thicknesses of 1, 5, 10, and 15 nm. The sensing performance of Au film composite nanomaterials with different Au layer thicknesses was tested at 100–250 °C and different nitrogen dioxide (NO2) concentrations ranging from 200 to 1000 ppb. The findings showed that the 10 nm Au–WO3 composite nanomaterial sensor had the most significant improvement in the performance of the pristine WO3 sensor compared with other Au–WO3 composite nanomaterial sensors, and the optimal operating temperature of the sensor was 175 °C. The composite nanomaterial sensor exhibited excellent selectivity when exposed to different gases and also exhibited high sensibility when exposed to low concentrations of NO2 under high humidity (80%). The mechanism of gas sensor performance improvement was also investigated. [ABSTRACT FROM AUTHOR]

MoS 2 nanochains were successfully prepared via facile electrospinning and a hydrothermal process. The morphology of MoS 2 nanochains was evaluated by field emission scanning electron microscopy and high-resolution transmission electron microscopy. A slurry composed of the MoS 2 nanochains was coated on a silver electrode to detect ammonia. The detection range of ammonia was between 25 and 500 ppm. MoS 2 nanochains offered outstanding sensing response, repeatable reproducibility, and excellent selectivity with a detection limit of 720 ppb. The responsiveness of MoS 2 nanochains to ammonia remained unchanged for 1 week., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Accumulating clinical and experimental evidence has suggested that Helicobacter pylori ( H. pylori ) infection-associated gastric cancer (GC) is associated with high rates of mortality and serious health effects. The majority of patients succumb to H. pylori infection-associated GC due to metastasis. Mesenchymal stem cells (MSCs), which have multipotent differentiation potential, may be recruited into the tumor-associated stroma. MSCs are crucial components of the H. pylori infection-associated GC microenvironment, and may be critical for GC cell migration. In this study, an MSCs/ H. pylori co-culture model was designed, and the effect of H. pylori -infected MSCs on the migration of GC cells was evaluated using a Transwell migration assay. H. pylori -infected MSC cytokine expression was evaluated using Luminex/ELISA. The expression of epithelial-mesenchymal transition (EMT) markers in the GC cells treated with supernatants from H. pylori -infected MSCs were detected by western blot analysis. The results demonstrated that the interaction between MSCs and H. pylori may induce GC cell migration, through secretion of a combination of cytokines that promote EMT in GC cells. The expression of phosphorylated forms of nuclear factor-κB (NF-κB) was observed to be increased in MSCs by H. pylori . Inhibition of NF-κB activation by pyrrolidine dithiocarbamate blocked the effects of H. pylori -infected MSCs on SGC-7901 human stomach adenocarcinoma cell migration. Overall, the results of the present study suggest that H. pylori -infected MSCs acquire a pro-inflammatory phenotype through secretion of a combination of multiple cytokines, a number of which are NF-κB-dependent. These cytokines enhance H. pylori infection-associated GC cell migration by promoting EMT in GC cells. The results of the present study provide novel evidence for the modulatory effect of MSCs in the tumor microenvironment and provide insight into the significance of stromal cell involvement in GC progression.