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Probiotics have emerged as promising alternatives to antibiotics for maintaining the health of the Chinese mitten crab (CMC, Eriocheir sinensis). However, the efficacy of probiotic application in CMC culture ecosystems remains uncertain. Intestinal microbiota is often as comprehensive indicators of aquatic animal health, but the effects of probiotics on CMC intestinal microbiota remain poorly understood. In this study, we used 16S rRNA gene amplicon sequencing to investigate the mechanisms underlying the changes of the intestinal microbial communities following short‐term probiotic application in CMC culture. Our data showed there was poor probiotic colonization in the intestines of pond‐cultured CMCs. The short‐term application of probiotics had no significant impact on the alpha‐diversity for the microbial communities; however, it significantly changed the beta‐diversity. Remarkably, the probiotics promoted butanoate metabolism of the CMC intestinal microbiota. According to network analysis, the microbiome of the CMC intestine manifested rapid responses to probiotic application, and cooperation between intestinal microbial communities may have been enhanced. Taken together, our results provide preliminary insights into the roles of probiotics in the CMC intestinal microbial ecosystem. [ABSTRACT FROM AUTHOR]

With low porosity and low permeability, shale reservoirs cannot be mined economically without large-scale hydraulic fracturing operation. However, abundant fracturing fluid will enter the reservoirs during the process of fracture. Nevertheless, there have not been specific research findings on the imbibition law of Fuling shale gas reservoir in China. In this study, an imbibition experiment was carried out on the shale core of Jiaoshiba block of Fuling shale gas reservoir to learn spontaneous imbibition characteristic of Fuling shale gas reservoir. Based on the experimental results, the imbibition process of Fuling shale gas reservoir fracturing fluid is divided into two stages. During the first stage, i.e., the former 30 hours, imbibition velocity is high, with the cumulative imbibition occupying more than 70% of the total imbibition; during the second stage, i.e., the latter 30 hours, the imbibition velocity substantially drops towards balance. There is a typical power function relationship between the average imbibition velocity and imbibition time, and this function relationship runs throughout the whole imbibition process. Nonetheless, the imbibition process of shale core cannot be described directly by the Handy equation. The imbibition velocity is closely related to clay mineral content and pore structure characteristics of shale core. The higher the clay mineral content, the higher the imbibition velocity. According to the relationship between the average imbibition velocity and imbibition time, we derived the estimation equation of fracture area formed by fractured shale gas well to estimate the fracture scale formed by shale gas well fracturing. [ABSTRACT FROM AUTHOR]

The Bayesian-based Source Tracker was performed to assess the contribution of rearing water and rotifer microbiota source to the larvae microbiota (Knights et al., 2011). Crab larvae, hatchery, microbiota, probiotics, source tracker Keywords: crab larvae; hatchery; microbiota; probiotics; source tracker EN crab larvae hatchery microbiota probiotics source tracker 3997 4002 6 07/21/21 20210801 NES 210801 High frequency of disease outbreaks severely restricts the development of mud crab ( I Scylla paramamosain i ) culture (Talib et al., 2016). [Extracted from the article]

In the field of plastic forming, ultrasonic vibration has the advantages of small forming force and high forming quality, and it has been introduced into a single-point incremental plastic forming technique with high flexibility and high precision. The ultrasonic vibration single-point incremental compound forming technology with all the above advantages has been achieved. To reveal the variation tendency of the forming force under ultrasonic vibration and single-point incremental coupling, the process parameters (layer spacing, tool head radius, and feed rate) and vibration parameters (frequency and amplitude) on the forming force of the composite technology were quantitatively analyzed by theory, simulation, and experiment. The simulation and experimental results showed that ultrasonic vibration can significantly reduce the forming force of the composite technology. Compared with the simulation results, the theoretical results are not only closer to the experimental results but also have a shorter computation time and better prediction effect on the forming force. The change in the process parameters has a linear effect on the forming force, the nonlinearity of the vibratory parameters influences the forming force, and the frequencies and amplitudes in a suitable range allow the forming force to reach a minimum value. These conclusions have some significance for further studies on the ultrasonic vibratory single-point incremental composite forming technology. [ABSTRACT FROM AUTHOR]