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This study compares the effects and bacterial community structure of single-chamber microbial fuel cells (MFCs) in the treatment of NH4+-containing wastewater with different chemical oxygen demand (COD)/N ratios, whilst simultaneously conducting stratification research on the cathode biofilm. To this end, five nitrifier pre-enriched single-chamber MFC reactors are established to treat five different COD/N wastewaters, respectively. The results show that MFCs with low COD/N have better NH4+-N removal, electrochemical performance, but the removal stability and COD removal effect are lower than MFCs with high COD/N. High-throughput sequencing reveals that the anode community structure is weakly affected by the COD/N and is dominated by Geobacter; however, the cathode community is complex and susceptible to the COD/N. Furthermore, the pH profile in the cathode biofilm is characterized by a pH microelectrode and fluorescence in situ hybridization (FISH) is used to confirm that the distribution trend of nitrifiers and denitrifiers in cathode biofilm.Although the combination of endogenous partial denitrification (EPD) and Anammox (EPD-AMX) were developed for deep-level nitrogen removal, the effects of different carbon source were not clear. In this study, the EPD performance was investigated comparatively with acetate (EPDA) and glucose (EPDG). Results revealed that through regulating chemical oxygen demand to phosphate ratio, Candidatus_Competibacter was highly enriched in EPDA (54.2%) and EPDG (51.3%), resulting high intracellular carbon storage efficiencies (90.2% and 85.3%, respectively). More stable nitrite accumulation was observed in EPDG than EPDA. But, higher specific nitrite generated rate (rNO2, 8.25 > 7.04 mgN·gVSS-1·h-1) and nitrate-to-nitrite transformation rate (NTR, 87.9% > 85.2%) were achieved in EPDA than those in EPDG. The functional bacterium was also shifted to Defluviicoccus in both EPDA (30.6%) and EPDG (25.8%). Moreover, with whether acetate or glucose, the EPD-AMX processes could achieve the same level of total nitrogen removal efficiencies (88.7% and 91.3%, respectively) via anammox mainly (87.8% and 89.4%, respectively).Bacterial cell division is orchestrated by the divisome, a protein complex centered on the tubulin homolog FtsZ. FtsZ polymerizes into a dynamic ring that defines the division site, recruits downstream proteins, and directs peptidoglycan synthesis to drive constriction. Recent studies have documented treadmilling of FtsZ polymer clusters both in cells and in vitro. Emerging evidence suggests that FtsZ dynamics are regulated largely by intrinsic properties of FtsZ itself and by the membrane anchoring protein FtsA. Although FtsZ dynamics are broadly required for Z-ring assembly, their role(s) during constriction may vary among bacterial species. These recent advances set the stage for future studies to investigate how FtsZ dynamics are physically and/or functionally coupled to peptidoglycan metabolic enzymes to direct efficient division.Glyphosate is the active ingredient of some of the most highly produced and used herbicides worldwide. The intensive applications of glyphosate-based herbicides and its half-life in water lead to its presence in many aquatic ecosystems. Whereas recent studies have reported neurotoxic effects of glyphosate including autism-related effects, most of them used extremely high (mg/L to g/L) concentrations, so it is still unclear if chronic, low environmentally relevant concentrations of this compound (ng/L to μg/L) can induce neurotoxicity. In this study we analyzed the neurotoxicity of glyphosate in adult zebrafish after waterborne exposure to environmentally relevant concentrations (0.3 and 3 μg/L) for two weeks. Our data showed that exposed fish presented a significant impairment of exploratory and social behaviors consistent with increased anxiety. The anterior brain of the exposed fish presented a significant increase in dopamine and serotonin levels, as well as in the DOPAC/dopamine and homovanillic acid/dopamine turnover ratios. Moreover, the expression of genes involved in the dopaminergic system, as th1, th2, comtb, and scl6a3 was downregulated. AOA hemihydrochloride ic50 Finally, the brain of exposed fish presented a significant increase in the catalase and superoxide dismutase activities, with a concomitant decrease of glutathione stores. These changes in the antioxidant defense system are consistent with the observed increase in oxidative stress, reflected by the increase in the levels of lipid peroxidation in the brain. The presented results show that current glyphosate concentrations commonly found in many aquatic ecosystems may have detrimental consequences on fish survival by decreasing exploration of the environment or altering social interactions. Furthermore, as zebrafish is also a vertebrate model widely used in human neurobehavioral studies, these results are relevant not only for environmental risk assessment, but also for understanding the risk of chronic low-dose exposures on human health.The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged less then 5 years and breastfeeding time less then 6 months enhanced the risks of pneumonia. Our study provided robust results that long-term levels of ambient PM2.5 and its constituents increased the risk of childhood pneumonia, especially NH4+, NO3- and OM.

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