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The effects of synchronous variations of influent salinity with the elevation of NH 4 + -N concentration on nitrification performance and microbial community structure of bioreactor are often ignored. In this study, we investigated the dynamic response of nitrifying activated sludge to synchronously increased salinity and ammonia loading rate (ALR) in a nitrification membrane bioreactor (MBR). We found that the increase in influent salinity above 1% (from 0.91 to 1.32%) led to the deterioration of the nitrification performance of the MBR. The combined inhibition effect of salinity (1.32%), free ammonia (FA, an average of 1.37 mg/L), and free nitrous acid (FNA, an average of 0.155 mg/L) on nitrite-oxidizing bacteria (NOB) resulted in long-term (35 days) nitrite accumulation. The further increase of salinity and ALR exhibited little influence on the nitrification performance of MBR after the activated sludge had adapted to high salinity (>1%), effective nitrification performance was achieved at high ALR up to 1.71 kg NH 4 + -N/m 3 ·d and high salinity (2.13%). The microbial analysis showed that the elevated salinity and accumulation of FNA reshaped the microbial community structure of ammonia-oxidizing bacteria (AOB) and NOB. The dominant species of AOB and NOB shifted from the salinity-resistant species Nitrosomonas aestuarii to the species Nitrosomonas mobilis with dual resistant to salinity and FNA, and from non-salinity-resistant species Candidatus Nitrospira defluvii to salinity-resistant species Nitrobacter winogradskyi and Nitrospira marina, respectively. Therefore, the salinity of 1% may be a critical level for the nitrification performance and the shift in the nitrifier community of activated sludge without salinity acclimation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Information on the association between tea drinking and semen quality is limited. Little is reported on whether tea drinking is benefit to sperm quality. This cross-sectional and longitudinal study was conducted between April 2017 and July 2018. Participants were healthy men who were screened as potential sperm donors recruited at the Hubei Province Human Sperm Bank of China. A structured questionnaires containing sociodemographic information, daily habits, sperm collection-related information was completed for each participant at interview. Repeated semen samples were taken to examine the sperm parameters, including sperm volume, sperm concentration, sperm count, progressive motility, and total motility. A total of 1385 men with 6466 sperm samples were included in this study. Two groups were compared: tea drinking men (389, 28.1%) and non-tea drinking men (996, 71.9%). Compared with subjects who never drink tea, the analyses showed that sperm concentration and total sperm count were higher in tea-consuming subjects. A 10-year period or more duration of tea drinking significantly increased semen concentrations by 16.27% (P < 0.05). Sperm concentration was increased in subjects with a frequency of tea drinking of 3 days or more per week (P < 0.05) or, among men who were occasional alcohol drinkers, when tea concentration was weak (P < 0.05). No evidence of trend effects (P for trend > 0.05) or interaction effects (P for interaction > 0.05) between tea consumption and sperm quality, respectively. Our findings provide evidence that tea drinking may improve male reproductive health. Long-term, frequent, weak tea drinking tends to increase sperm quality among men with low BMI or health-related behaviors like smoking or alcohol intake., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The effects of cast iron pipe corrosion on nitrogenous disinfection by-products formation (N-DBPs) in drinking water distribution systems (DWDSs) were investigated. The results verified that in the effluent of corroded DWDSs simulated by annular reactors with corroded cast iron coupons, typical N-DBPs, including haloacetamides, halonitromethanes, and haloacetonitriles, increased significantly compared with the influent of DWDSs. In addition, more dissolved organic carbon, adenosine triphosphate, and iron particles were simultaneously detected in the bulk water of corroded DWDSs, thereby indicating that abundant iron particles acted as a "protective umbrella" for microorganisms. Under the condition of corroded DWDSs, the extracellular polymeric substances gradually exhibited distinct characteristics, including a higher content and lower flocculation efficiency, thereby resulting in a large supply of N-DBPs precursors. Corroded cast iron pipes, equivalent to a unique microbial interface, induced completely distinct microbial community structures and metabolic functions in DWDSs, thereby enhancing the formation of N-DBPs. This is the first study to successfully reveal the interactions among iron particles, biofilms, and chlorine in DWDSs, which may help to fully understand the biofilm transformation and microbial community succession in DWDSs., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Change in water quality was investigated with laboratory-scale ozone-biological activated carbon filters using copper-modified granular activated carbon (Cu/GAC) and unmodified granular activated carbon (GAC). In the first seven days of the experimental period, Cu/GAC removed organic matter more efficiently owing to its enhanced adsorption capacity. As the running time increased, the amount of disinfection by-products (DBPs), dissolved organic carbon, and extracellular polymeric substances (EPS) increased sharply in the effluent of the Cu/GAC filter (CCW). More importantly, the EPS suspended in the CCW exhibited weaker flocculating efficiency and hydrophobicity, causing more active chemical reactions between chlorine and EPS substances. The copper species significantly limited the microbial biomass (0.01 nmol/L adenosine triphosphate) but stimulated the secretion of significant amounts of EPS by microorganisms for self-protection. Furthermore, the microbial community in the bulk water was successfully shaped by Cu/GAC, resulting in a continuous supply of EPS-derived DBP precursors and a sharp rise in chlorine consumption in the downstream drinking water distribution. Therefore, use of modified GAC materials, similar to Cu/GAC, as carrier materials for biological activated carbon (BAC) treatment remains controversial, despite enhanced pollutant adsorption capacity. This is the first study to reveal the mechanism of BAC-modified materials for water quality stability. The study potentially contributes to a comprehensive understanding of the effects of biofilm transformation and microbial community succession on drinking water quality. These results showed that tap water safety risks could be reduced by improving BAC pretreatment in drinking water treatment plants., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The effects of trace phosphate concentrations (0, 0.3 and 0.6 mg/L) in water source were investigated on microbial stability of the drinking water distribution systems (DWDSs). Obviously, the results verified that in the effluent of DWDSs simulated by annular reactors (ARs), the total microbial biomass and the absolute concentration of opportunistic pathogens such as Legionella pneumophila, Mycobacterium avium, and Hartmanella vermiformis increased significantly with phosphate concentration increasing. Based on X-ray powder diffractometer and zeta potentials measurement, trace phosphate did change physicochemical properties of corrosion products, hence promoting microbes escape from corrosion products to bulk water to a certain extent. Stimulated by chlorine disinfectant and phosphate, the extracellular polymeric substances (EPS) from the suspended biofilms of AR-0.6 gradually exhibited superior characteristics including higher content, flocculating efficiency, hydrophobicity and tightness degree, contributing to formation of large-scale suspended biofilms with strong chlorine-resistance ability. However, the disinfection by-products concentration in DWDSs barely changed due to the balance of EPS precursors contribution and biodegradation effect, covering up the microbiological water quality risk. Therefore, more attention should be paid to the trace phosphorus polluted water source though its concentration was much lower than wastewater. This is the first study successfully revealing the influence mechanism of trace phosphate on microbial stability in DWDSs, which may help to fully understand the biofilms transformation and microbial community succession in DWDSs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Graphitic carbon nitride (g-C 3 N 4 ) has enormous potentials for photocatalysis, yet it only possesses moderate activity because of excitonic effects and sluggish charge transfer. Here, we develop a novel two-dimensional g-C 3 N 4 /WO 3 /MoS 2 (CWM) ternary nanocomposite through a facile co-calcination and a hydrothermal process to reach a highly-efficient photocatalyst for organic pollutant elimination under visible light. The WO 3 and MoS 2 nanoparticles were dispersed on the ultra-thin g-C 3 N 4 nanosheets, in which the electronegative g-C 3 N 4 facilitates formation of oxygen vacancies in WO 3 . Compared to pure g-C 3 N 4 , WO 3 , and binary composites, CWM exhibited higher photocatalytic activities for various organic pollutants removal under visible light irradiation. For instance, the CWM showed a removal ratio of ∼99% for RhB after only 10 min irradiation of visible light (λ > 420 nm) and nearly 100% for ciprofloxacin after 2 h of operation. The results showed that OH radicals are the main active species for organic degradation, which suggests a direct Z-scheme heterojunction in CWM that improved spatial separation of charge carries. Furthermore, the collection of electrons is significantly enhanced by MoS 2 for oxygen reduction reaction, and the increased oxygen vacancies of WO 3 further enhanced the separation of electron-hole pairs; therefore, it led to an effective suppression of charge carriers recombination. The above synergistic effects of ternary photocatalyst result in higher photocatalytic oxidation performance for wastewater treatment compared with pure WO 3 , g-C 3 N 4 and their binary composites., (Copyright © 2019. Published by Elsevier Ltd.)

Drinking water distribution systems (DWDS) may be a "Trojan Horse" for some waterborne diseases caused by opportunistic pathogens (OPs). In this study, two simulated DWDS inoculated with groundwater were treated with chlorine (Cl 2 ) and ultraviolet/chlorine (UV/Cl 2 ) respectively to compare their effects on the OPs distributed in four different phases (bulk water, biofilms, corrosion products, and loose deposits) of DWDS. 16S rRNA genes sequencing and qPCR were used to profile microbial community and quantify target genes of OPs, respectively. Results showed that UV/Cl 2 was more effective than single Cl 2 to control the regrowth of OPs in the water with the same residual chlorine concentration. However, the OPs inhabiting the biofilms, corrosion products, and loose deposits seemed to be tolerant to UV/Cl 2 and Cl 2 , demonstrating that OPs residing in these phases were resistant to the disinfection processes. Some significant microbial correlations between OPs and Acanthamoeba were found by Spearman correlative analysis (p < 0.05), demonstrating that the ecological interactions may exist in the DWDS. 16S rRNA genes sequencing of water samples revealed a significant different microbial community structure between UV/Cl 2 and Cl 2 . This study may give some implications for controlling the OPs in the DWDS disinfected with UV/Cl 2 ., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Effects of sulfadiazine and ciprofloxacin on microorganisms in biofilm of drinking water distribution systems (DWDSs) were studied. The results verified that the increases of 16S rRNA for total bacteria and bacterial genus Hyphomicrobium were related to the promotion of antibiotic resistance genes (ARGs) and class 1 integrons (int1) in DWDSs with sulfadiazine and ciprofloxacin. Moreover, the bacteria showed higher enzymatic activities in DWDSs with sulfadiazine and ciprofloxacin, which resulted in more production of extracellular polymeric substances (EPS). The higher contents of EPS proteins and secondary structure β-sheet promoted bacterial aggregation and adsorption onto surface of pipelines to form biofilm. EPS can serve as a barrier for the microorganisms in biofilm. Therefore, the biofilm bacterial communities shifted and the 16S rRNA for total bacteria increased in DWDSs with antibiotics, which also drove the ARGs promotion. Furthermore, the two antibiotics exhibited stronger combined effects than that caused by sulfadiazine and ciprofloxacin alone., (Copyright © 2018. Published by Elsevier Ltd.)

Algae and mercury (Hg) are ubiquitous in marine environments. In this study, we investigated the effects of a typical marine algae of diatom Skeletonema costatum on Hg methylation by an iron-reducing bacterium of Geobacter sulfurreducens (G. sulfurreducens) PCA. In the absence of Skeletonema costatum, the bacterial MeHg production rate maximized at 104.06 ± 11.7 ng L -1 h -1 with a high Hg level, while the highest methylation efficiency was achieved at a low Hg concentration. The existence of Skeletonema costatum greatly inhibited the capability of G. sulfurreducens PCA to methylate Hg. With the increase in algal biomass, there was a significant mitigation of MeHg formation and Hg 0 release, leaving a considerable proportion of immobilized Hg 2+ species (up to 47%) associated with algal cell materials. These results suggest that marine algae are crucial in determining the bioavailability of Hg contaminants and the methylating potential of G. sulfurreducens PCA., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Academics researchers and "citizen scientists" from 22 countries confirmed that yellow mealworms, the larvae of Tenebrio molitor Linnaeus, can survive by eating polystyrene (PS) foam. More detailed assessments of this capability for mealworms were carried out by12 sources: five from the USA, six from China, and one from Northern Ireland. All of these mealworms digested PS foam. PS mass decreased and depolymerization was observed, with appearance of lower molecular weight residuals and functional groups indicative of oxidative transformations in extracts from the frass (insect excrement). An addition of gentamycin (30 mg g -1 ), a bactericidal antibiotic, inhibited depolymerization, implicating the gut microbiome in the biodegradation process. Microbial community analyses demonstrated significant taxonomic shifts for mealworms fed diets of PS plus bran and PS alone. The results indicate that mealworms from diverse locations eat and metabolize PS and support the hypothesis that this capacity is independent of the geographic origin of the mealworms, and is likely ubiquitous to members of this species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The cathodic reduction of complex-state copper(II) was investigated in a dual chamber microbial fuel cell (MFC). The inner resistance of MFC system could be reduced in the presence of ionizing NH(4)(+), however, mass transfer was hindered at higher ammonia concentration. Thermodynamic and electrochemical analyses indicated that the processes of complex dissociation and copper reduction were governed by the ratio of T[Cu]:T[NH(3)] and the pH of solution. The reduction of Cu(NH(3))(4)(2+) could be achieved via two possible pathways: (1) releasing Cu(2+) from Cu(NH(3))(4)(2+), then reducing Cu(2+) to Cu or Cu(2)O and (2) Cu(NH(3))(4)(2+) accepting an electron and forming Cu(NH(3))(2)(+), and depositing as Cu or Cu(2)O consequently. At initial concentration of 350 mg T[Cu] L(-1), copper removal efficiency of 96% was obtained at pH=9.0 within 12 h (with △Cu/△COD=1.24), 84% was obtained at pH=3.0 within 8 h (with △Cu/△COD=1.72). Cu(NH(3))(4)(2+) was reduced as polyhedral deposits on the cathode., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

AgBr was creatively immobilized on a magnetic substrate (SiO(2)-coated Fe(3)O(4) nanoparticle, SFN) to achieve magnetic separation after visible light-driven photocatalytic oxidation (PCO). The resulted Ag/AgBr/SFN was characterized by TEM, vibrating sample magnetometer and other techniques. It is found that the average diameter of the Ag/AgBr/SFN particle is less than 20 nm. The typical superparamagnetic behavior of Ag/AgBr/SFN implies that the catalyst can be magnetically separated. The physicochemical features of the used Ag/AgBr/SFN after visible light irradiation were not dramatically changed by X-ray diffraction, UV-Vis diffuse reflectance spectra and Fourier transform-infrared analysis. SiO(2) interlayer was proven to slightly increase the degradation efficiency for an azo dye Acid Orange 7. UV-Vis spectra and HPLC analysis indicated that the dye was oxidized and decomposed. The photoactivity of Ag/AgBr/SFN was partly maintained after successive PCO under visible light. In order to evaluate the roles of e(-)-h(+) pairs and reactive oxygen species, the quenching effect was examined by employing Ag/AgBr/SFN and commercial TiO(2) (P-25) under visible light (lambda>400 nm) and UV-A irradiation, respectively. Active h(+) and the resulting (*)OH played the major roles for degradation. The effect of active h(+) and (*)OH were proven to be highly dependent on the concentration of photocatalysts. The effect of (*)OH was more obvious for P-25, while that of active h(+) was more predominant for Ag/AgBr/SFN.