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• SAE1 expression increased in rats and patients with hepatic fibrosis, providing direct evidence that SAE1 promotes hepatic fibrosis progression. • GA inhibited SAE1 expression and induced ferroptosis, inhibiting the activation of hepatic stellate cells in vitro. • GA induced ferroptosis and alleviated the progression of hepatic fibrosis in vivo. Finding a drug for early intervention in the hepatic fibrosis process has important clinical significance. Previous studies have suggested SUMOylation as a potential target for intervention in hepatic fibrosis. However, the role of SAE1, a marker of SUMOylation, in hepatic fibrosis is unknown. Additionally, whether ginkgolic acid (GA), a SUMOylation inhibitor, inhibits hepatic fibrosis by inhibiting SUMO1-activating enzyme subunit 1 (SAE1) should be further investigated. Liver tissues of patients with hepatic cirrhosis and a rat model of hepatic fibrosis constructed with CCl 4 (400 mg/kg, twice weekly) or TAA (200 mg/kg, twice weekly) were selected, and the degree of hepatic fibrosis was then evaluated using H&E, Sirius red, and Masson's trichrome staining. After knockdown or overexpression of SAE1 in hepatic stellate cells, the expression levels of ferroptosis and hepatic fibrosis markers were measured in vitro. After intervention with a ferroptosis inhibitor, the expression levels were again measured in vivo and in vitro. We first demonstrated that SAE1 increased in patients with hepatic cirrhosis. Subsequently, testing of the rat hepatic fibrosis model confirmed that GA reduced the expression of SAE1 and improved hepatic fibrosis in rats. Then, we used hepatic stellate cell lines to confirm in vitro that GA inhibited SAE1 expression and induced ferroptosis, and that overexpression of SAE1 or inhibition of ferroptosis reversed this process. Finally, we confirmed in vivo that GA induced ferroptosis and alleviated the progression of hepatic fibrosis, while inhibiting ferroptosis also reversed the progression of hepatic fibrosis in rats. SAE1 is a potential anti-fibrotic target protein, and GA induces ferroptosis of hepatic stellate cells by targeting SAE1 to exert an anti-hepatic fibrosis effect, which lays an experimental foundation for the future clinical application of its anti-hepatic fibrosis effect. Ginkgolic acid inhibits the expression of SAE1 and induces ferroptosis to exert an anti–hepatic fibrosis effect in vivo and vitro. [Display omitted] [ABSTRACT FROM AUTHOR]

Reducing the power consumption of the air supply system has become one of the bottleneck problems for developing PEMFCs. This paper proposes the two-phase expansion of air and liquid water in a twin-screw expander to recover the thermal energy of water simultaneously and achieve quasi-isothermal expansion, aiming at increasing the recovery power of the expander and thus reducing the power consumption of the air supply subsystem in PEMFCs. A mathematical model of the working process for a twin-screw expander is constructed to evaluate the performance improvement of the expander caused by the two-phase expansion at variational rotating speed, inlet pressure, and air stoichiometry ratio. The influence mechanisms of sealing and heat exchange of water are revealed. Results show that the sealing effect of water couldn't bring out obvious performance improvement of the expander mainly due to the limited water generated in the fuel cell stack and flowing into the expander. However, sufficient heat exchange between air and water can effectively improve the expander performance and would have a more significant effect under the condition of less gas leakage. The maximum increment of specific power could reach 10.8% compared to the dry-running condition. [Display omitted] • Introduce the two-phase expansion into TSE used in PEMFCs. • The potential for performance improvement through the two-phase expansion is clarified. • The maximum increment of specific power could reach 10.8% compared to the dry-running condition. [ABSTRACT FROM AUTHOR]

The water-lubricated twin-screw air compressor is very suitable for applications in high-pressure PEMFCs in distributed power generation, for it can provide absolutely oil-free air. Power consumption distribution is a significant characteristic for clarifying the influence mechanism of water injection and lubrication, which could provide the optimizing direction for performance enhancement. Hence, a mathematical model is constructed in this paper, aiming to analyze the power consumption distribution in different positions of the compressor at different rotating speed, including indicated power of dry air, water vapor and liquid water, friction power in the rotor chamber, friction power of radial journal bearings, thrust bearings and the lip seal. Results show that thrust bearings account for the largest amount of total power loss by over 52%, followed by indicated power of liquid water, radial journal bearings, while the indicated power of water vapor, friction powers in the rotor chamber and of the lip seal are minor power losses. This is very different from the common oil-injected twin-screw compressors, in which the friction power in the rotor chamber is also the dominant power loss. It illustrates the advantage of the low friction coefficient of water for sealing clearances in the water-lubricated twin-screw air compressor. [Display omitted]. • Introduce the WLTSAC into high-pressure PEMFCs for distributed power generation applications. • The power consumption distribution characteristics of the WLTSAC are identified. • Reducing friction loss of thrust bearings and indicated power of liquid water is the key to performance improvement. • The mechanical efficiency of the WLTSAC keeps a nearly constant value of about 83% at different rotating speeds. [ABSTRACT FROM AUTHOR]

The mechanism driving the dissemination of antibiotic resistance genes (ARGs) in drinking water supply systems (DWSSs) with multiple barriers remains poorly understood despite several recent efforts. Phosphorothioate (PT) modifications, governed by dndABCDE genes, occur naturally in various bacteria and involve the incorporation of sulfur into the DNA backbone. PT is regarded as a mild antioxidant in vivo and is known to provide protection against bacterial genomes. We combined quantitative polymerase chain reaction, metagenomic, and network analyses for the water treatment process and laboratory-scale experiments for chlorine treatment using model strains to determine if DNA PT modification occurred in DWSS and facilitated the dissemination of mobilized colistin resistance-1 (mcr-1) and New Delhi metallo-β-lactamase-1 (bla NDM-1) in DWSS. Our results indicated that the relative abundance of dndB increased in the effluent, compared with the influent, in the water treatment plants. Presence of dndB copies had a positive correlation with the concentration of chloramine disinfectant. Network analysis revealed Bdellovibrio as a potential host for MCR genes, NDM genes, and dndB in the DWSS. E. coli DH10B (Wild-type with the dndABCDE gene cluster and ΔdndB) model strains were used to investigate resistance to chlorine treatment at the concentration range of 0.5–3 mg/L. The resistance of the wild-type strain increased with increasing concentration of chlorine. DNA PT modification protected MCR- and NDM -carrying bacteria from chloramine disinfection during the water treatment process. The higher relative abundance of ARGs in the effluent of the water treatment plants may be due to the resistance of DNA PT modification to chloramine disinfection, thereby causing the enrichment of genera carrying MCR , NDM , and dndB. This study provides a new understanding on the mechanism of ARG dissemination in DWSS, which will help to improve the performance of drinking water treatment to control the risk associated with antibiotic-resistant bacteria. Image 1 • dndB positively correlates with the concentration of chloramine disinfectants. • dndB positively correlates with MCR and NDM in water supply system. • Bdellovibrio is the core genera carrying MCR , NDM and dndB. • DNA PT modification can protect ARB escape chloramine disinfection. Main finding: DNA phosphorothioate modification mediates the dissemination of antibiotic resistance genes, mcr-1 and bla NDM-1 , in drinking water supply system. [ABSTRACT FROM AUTHOR]

Mcr-1 and bla NDM-1 antibiotic resistance genes (ARGs) confer resistance to colistins and carbapenems, which are often antibiotics used as a last resort in tertiary care hospitals. Dissemination of these two ARGs in drinking water supply systems and their effect on healthy gut bacteria are poorly studied. In this study, the dissemination of mcr-1 and bla NDM-1 in a drinking water supply system, and their effect on the antibiotic resistance of mouse gut bacteria are explored. Metagenome analysis revealed that source water (Taipu river and Jinze reservoir) was polluted with ARGs. Mcr-1 and bla NDM-1 can be disseminated through the water distribution system. Even advanced water treatments (ozone and biological activated carbon (BAC)) could not effectively remove mcr-1 and bla NDM-1. Low concentrations of chloramine disinfectants in the water distribution system were not effective at limiting ARG abundance. Mobile genetic elements were also found to play a major role in the dissemination of ARGs via horizontal gene transfer (HGT) throughout the water supply system. Statistical analysis revealed that there was no effect of temperature on the abundance of mcr-1 and bla NDM-1 throughout the water supply system. A last resort ARG, mcr-1 can disseminate from drinking water to the healthy mouse gut. The presence of mcr-1 in a strain belonging to Enterococcus hirae , which is different from the strain belonging to the Bacillus cereus group isolated from drinking water, strongly supports the phenomena of HGT inside the gut. This research provides novel insights into the role of drinking water in disseminating ARGs to the gut and strongly suggests that drinking water may also play a major role apart from other factors known to be involved in the prevalence of last resort ARGs in the gut. Image 1 • mcr-1 and bla NDM-1 were found to disseminate from source to tap in water supply system. • Advanced water treatment process could not effectively remove mcr-1 and bla NDM-1. • Chloramine disinfection had no effect on elimination of mcr-1 and bla NDM-1. • Last resort ARG mcr-1 could disseminate from drinking water to the gut via HGT. • Drinking water is one of the reasons of last resort ARGs transfer in a healthy gut. mcr-1 and bla NDM-1 can disseminate through drinking water supply systems and mcr-1 was found to disseminate from drinking water to the mouse gut. [ABSTRACT FROM AUTHOR]

This research presents a numerical method to analyze the propagation characteristics of guided waves in multi-layered anisotropic composite laminates. The dispersion equations were derived theoretically, while the displacement and stress components of each layer are expressed in the form of state vectors, by combining the state-vector formalism and the Legendre polynomials (SVF-LP). The displacement fields are fitted approximately by Legendre polynomials, and the system of linear equations are constructed by the orthogonal projection. The eigenvalue/eigenvector solution is established to compute the phase dispersion curves instead of solving the transcendental dispersion equations. This overcomes the problem of missing roots in traditional matrix method effectively. In order to verify the robustness of the SVF-LP, three cases of multi-layered laminates, formed by isotropic material, unidirectional carbon-fiber epoxy prepreg and fiber-metal laminate (GLARE 3-3/2) are investigated, respectively. The influences of fiber angle change and the stacking sequence are primarily analyzed, on the dispersion characteristics and the displacement and stress profiles. The matrix method is also carried out to compare the accuracy of this proposed method, which is done by the commercial software Disperse. Finally, the displacement and stress profiles of fundamental modes of the guided waves in an arbitrary lay-up quasi-isotropic plate at a given frequency is discussed in details. [ABSTRACT FROM AUTHOR]