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Background: Planetary plastic pollution poses a major threat to ecosystems and human health in the Anthropocene, yet its impact on biogeochemical cycling remains poorly understood. Waterlogged rice paddies are globally important sources of CH 4 . Given the widespread use of plastic mulching in soils, it is urgent to unravel whether low-density polyethylene (LDPE) will affect the methanogenic community in flooded paddy soils. Here, we employed a combination of process measurements, short-chain and long-chain fatty acid (SCFAs and LCFAs) profiling, Fourier-transform ion cyclotron resonance mass spectrometry, quantitative PCR, metagenomics, and mRNA profiling to investigate the impact of LDPE nanoplastics (NPs) on dissolved organic carbon (DOC) and CH 4 production in both black and red paddy soils under anoxic incubation over a 160-day period., Results: Despite significant differences in microbiome composition between the two soil types, both exhibited similar results to NPs exposure. NPs induced a change in DOC content and CH 4 production up to 1.8-fold and 10.1-fold, respectively. The proportion of labile dissolved organic matter decreased, while its recalcitrance increased. Genes associated with the degradation of complex carbohydrates and aromatic carbon were significantly enriched. The elevated CH 4 production was significantly correlated to increases in both the PCR-quantified mcrA gene copy numbers and the metagenomic methanogen-to-bacteria abundance ratio. Notably, the latter was linked to an enrichment of the hydrogenotrophic methanogenesis pathway. Among 391 metagenome-assembled genomes (MAGs), the abundance of several Syntrophomonas and Methanocella MAGs increased concomitantly, suggesting that the NPs treatments stimulated the syntrophic oxidation of fatty acids. mRNA profiling further identified Methanosarcinaceae and Methanocellaceae to be the key players in the NPs-induced CH 4 production., Conclusions: The specific enrichment of Syntrophomonas and Methanocella indicates that LDPE NPs stimulate the syntrophic oxidation of LCFAs and SCFAs, with Methanocella acting as the hydrogenotrophic methanogen partner. Our findings enhance the understanding of how LDPE NPs affect the methanogenic community in waterlogged paddy soils. Given the importance of this ecosystem, our results are crucial for elucidating the mechanisms that govern carbon fluxes, which are highly relevant to global climate change., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Mounting evidence suggests that gut microbial composition and its metabolites, including short-chain fatty acids (SCFAs), have beneficial effects in regulating host immunogenicity to vaccines. However, it remains unknown whether and how SCFAs improve the immunogenicity of the rabies vaccine. In this study, we investigated the effect of SCFAs on the immune response to rabies vaccine in vancomycin (Vanco)-treated mice and found that oral gavage with butyrate-producing bacteria ( C. butyricum ) and butyrate supplementation elevated RABV-specific IgM, IgG, and virus-neutralizing antibodies (VNAs) in Vanco-treated mice. Supplementation with butyrate expanded antigen-specific CD4 + T cells and IFN-γ-secreting cells, augmented germinal center (GC) B cell recruitment, promoted plasma cells (PCs) and RABV-specific antibody-secreting cells (ASCs) generation in Vanco-treated mice. Mechanistically, butyrate enhanced mitochondrial function and activated the Akt-mTOR pathway in primary B cells isolated from Vanco-treated mice, ultimately promoting B lymphocyte-induced maturation protein-1 (Blimp-1) expression and CD138 + PCs generation. These results highlight the important role of butyrate in alleviating Vanco-caused humoral immunity attenuation in rabies-vaccinated mice and maintaining host immune homeostasis. IMPORTANCE The gut microbiome plays many crucial roles in the maintenance of immune homeostasis. Alteration of the gut microbiome and metabolites has been shown to impact vaccine efficacy. SCFAs can act as an energy source for B-cells, thereby promoting both mucosal and systemic immunity in the host by inhibiting HDACs and activation of GPR receptors. This study investigates the impact of orally administered butyrate, an SCFA, on the immunogenicity of rabies vaccines in Vanco-treated mice. The results showed that butyrate ameliorated humoral immunity by facilitating the generation of plasma cells via the Akt-mTOR in Vanco-treated mice. These findings unveil the impact of SCFAs on the immune response of the rabies vaccine and confirm the crucial role of butyrate in regulating immunogenicity to rabies vaccines in antibiotic-treated mice. This study provides a fresh insight into the relationship of microbial metabolites and rabies vaccination., Competing Interests: The authors declare no conflict of interest.

Aims: To test the relationship between practice environment and turnover intention, considering the moderation of perceived organizational support (POS) and the mediation of general well-being (GWB) and occupational burnout (OB) among the nurse population., Design: A cross-sectional survey design., Methods: Based on a sample of 474 nurses from two hospitals between May 2020 and September 2021, a moderated multi-mediation model was tested in which GWB and OB served as two mediators between practice environments and nurses' turnover intention, and POS was regarded as a moderator between practice environments and GWB., Results: This current study supported a moderated multi-mediation model where the relationship between practice environment and turnover intention (B = 0.33, p < 0.001) was mediated by GWB (B = 0.17, p < 0.001) and OB (B = 0.18, p < 0.001), and POS moderated the effect of practice environment and GWB (B = 0.19, p < 0.001)., Public Contribution: The findings of this study can inform the design of effective organizational support and meet nurse emotional needs programmes to reduce the turnover intention among nurses., (© 2023 The Authors. Nursing Open published by John Wiley & Sons Ltd.)

Fourier domain mode-locking has been used in fiber Bragg grating interrogation for high-speed and long-distance measurement. But the delays induced by long fiber between multisensors and interrogation systems result in nonneglected wavelength error in this high-speed wavelength-swept system. More seriously, the cross-sweep cycle and different distance delays may cause the delay-disorder problem which makes the system unable to determine the order of the delayed peaks and unable to address the location of sensors with corresponding wavelength-encoding characteristics. This paper proposes a novel delayed-peak recognition and calibration method in which the laser works at four different scanning rates. We confirm the relationship between delayed peaks and sensors with recognition parameters at two low rates and eliminate wavelength error at two high rates. Experimental results show that this method recognizes the delayed peaks correctly and calibrates wavelength accurately with error below 10 pm.

In order to endow environmental protection features to dentifrice, hydroxyapatite (HA) was added to ordinary dentifrice. The effects on dentinal tubule occlusion and surface mineralization were compared after brushing dentine discs with dentifrice with or without HA. The two types of dentifrice were then added to 100 µg/ml of hexavalent chromium cation (Cr(6+)) solution in order to evaluate their capacities of adsorbing Cr(6+) from water. Our results showed that the dentifrice containing HA was significantly better than the ordinary dentifrice in occluding the dentinal tubules with a plugging rate greater than 90%. Moreover, the effect of the HA dentifrice was persistent and energy-dispersive spectrometer (EDS) revealed that the atomic percentages of calcium and phosphorus on the surface of dentine discs increased significantly. Adding HA to ordinary dentifrice significantly enhanced the ability of dentifrice to adsorb Cr(6+) from water with the removal rate up to 52.36%. In addition, the sorption was stable. Our study suggests that HA can be added to ordinary dentifrice to obtain dentifrice that has both relieving dentin hypersensitivity benefits and also helps to control environmental pollution.