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Microorganisms play an important role in aquaculture systems; however, we know a little about their contributions to nitrogen cycling and balancing nitrite conversion. Both 16S rRNA pyrosequencing‐based analysis and quantifying functional genes related to nitrite conversion were performed to study the niche function of microbial flora in a marine aquaculture system. During the whole aquaculture period, bacterial abundance was maintained at a high level (1010−11 copies/L), which was 105 times larger than that of archaea. Proteobacteria and Bacteroidetes dominated the bacterial communities, and the core species mainly belonged to the families Rhodobacteraceae and Flavobacteriaceae. Bacterial denitrifiers and dissimilatory nitrate reduction to ammonium (DNRA) bacteria were highly abundant and played key roles in the conversion and removal of nitrite, and the narG and nirK genes were highly correlated with the variation in nitrate and nitrite contents. Ammonia‐ and nitrite‐oxidizing microorganisms might contribute little to the conversion of nitrite during the whole aquaculture, although high abundance of bacterial amoA gene was detected at Day 131. The nitrite conversion‐related microbial community consisted dominantly of diverse microorganisms, and Flavobacteriaceae, Rhodobacteraceae and Alteromonadaceae were the main groups. Temperature and NH4+ had the largest impact on the microbial community. These results indicated that in eutrophic water of shrimp aquaculture, the core microbiome, including Flavobacteriaceae and Rhodobacteraceae, and other denitrifiers, plays an important role in nitrite cycling and maintaining the health of the aquaculture system. [ABSTRACT FROM AUTHOR]

Household humidification is widely practiced to combat dry indoor air. While the benefits of household humidification are widely perceived, its implications to the indoor air have not been critically appraised. In particular, ultrasonic humidifiers are known to generate fine particulate matter (PM). In this study, we first conducted laboratory experiments to investigate the size, quantity, and chemical composition of PM generated by an ultrasonic humidifier. The mass of PM generated showed a correlation with the total alkalinity of charge water, suggesting that CaCO3 is likely making a major contribution to PM. Ion chromatography analysis revealed a large amount of SO42− in PM, representing a previously unrecognized indoor source. Preliminary results of organic compounds being present in humidifier PM are also presented. A whole‐house experiment was further conducted at an actual residential house, with five low‐cost sensors (AirBeam) monitoring PM in real time. Operation of a single ultrasonic humidifier resulted in PM2.5 concentrations up to hundreds of μg m−3, and its influence extended across the entire household. The transport and loss of PM2.5 depended on the rate of air circulation and ventilation. This study emphasizes the need to further investigate the impact of humidifier operation, both on human health and on the indoor atmospheric chemistry, for example, partitioning of acidic and basic compounds. [ABSTRACT FROM AUTHOR]

Diphenyl difluoroketone (EF24), a curcumin analog, is a promising anticancer compound that exerts its effects by inhibiting cell proliferation and inducing apoptosis. However, the efficacy of EF24 against cancer metastasis, particularly in hepatocellular carcinoma (HCC), remains elusive. In this study, the effect of EF24 on HCCLM-3 and HepG2 cell migration and invasion was detected by wound healing and transwell assay, respectively. The results revealed that EF24 suppressed the migration and invasion of both HCCLM-3 and HepG2 cells. Furthermore, EF24 treatment decreased the formation of filopodia on the cell surface and inhibited the phosphorylation of Src in both cell lines, which may help contribute towards understanding the mechanism underlying the suppressive effect of EF24 on HCC migration and invasion. Additionally, the expression of total- and phosphorylated-Src in primary HCC tissues and their paired lymph node metastatic tissues was detected, and phosphorylated-Src was found to be associated with HCC lymph node metastasis. The results of this study suggest that Src is a novel and promising therapeutic target in HCC and provide evidence to support the hypothesis that EF24 may be a useful therapeutic agent for the treatment of HCC. [ABSTRACT FROM AUTHOR]