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© 2019 Alkaline (especially pH 10) anaerobic fermentation of waste activated sludge (WAS) has been reported to be an effective approach for hydrogen production through inhibiting the homoacetogenesis and methanogenesis. However, the potential effect of the widespread microplastics in sludge on the performance of hydrogen production has never been reported. To fill this knowledge gap, the dominant polyethylene terephthalate (PET) microplastics in WAS were selected as the model microplastics to evaluate their influences on hydrogen production during alkaline anaerobic fermentation of WAS as well as the key mechanisms involved. Experimental results demonstrated that hydrogen production from WAS decreased in the presence of PET microplastics (i.e., 10, 30 and 60 particles/g-TS) compared to the control, with the hydrogen yield at 60 particles/g-TS being only 70.7 ± 0.9% of the control. Although the hydrogen consumption (i.e., homoacetogenesis and methanogenesis) was restrained under alkaline (pH 10) condition, PET microplastics inhibited hydrolysis, acidogenesis and acetogenesis in alkaline WAS anaerobic fermentation, leading to the inhibitory effect on hydrogen production. This was further confirmed by the microbial analysis, which clearly showed PET microplastics caused the shift of the microbial community toward the direction against hydrolysis-acidification. Mechanism studies revealed that PET microplastics carried on their negative influence mainly through leaching the toxic di-n-butyl phthalate (DBP). The reactive oxygen species (ROS) and live/dead staining tests indicated that the increased ROS was induced by PET microplastics, causing more cells dead, which further resulted in the decreased production of hydrogen.

© 2019 American Chemical Society. In this study, novel hexagonal K2W4O13 (h-K2W4O13) nanowires were strategically synthesized via a facial hydrothermal method, which exhibited excellent adsorption capacities for wastewater treatment. The inorganic agent K2SO4 was used as a structure-directing agent to scaffold the tunnel structure of h-K2W4O13 and form the one-dimensional structure. Through increasing the relative molar ratio of K2SO4 to Na2WO4 precursor, the pure-phase h-WO3 nanorods and h-K2W4O13 nanowires were obtained, attributing to the competitive electrostatic adsorption between K+ ions and Na+ ions on h-WO3 nuclei. With a smaller hydrated radius in the solution (dK+ = 3.31 Å, dNa+= 3.58 Å), K+ exhibited superior affinity compared to Na+ with the negatively charged h-WO3 nuclei because of a larger charge density, resulting in the formation of h-K2W4O13. Adsorption experimental results showed that 89.4% of methylene blue was removed by h-K2W4O13 in the first 5 min (99% in 1 h) and the maximum uptake capacity reached 204.08 mg g-1. In addition, the novel h-K2W4O13 exhibited acid or alkali resistance and good reusability, revealed by the stable adsorption capacity in a wide pH range of 3.0-11.0 and five-run recycle tests. The large specific area, high proportion of effective pore volume, and abundant hydroxyl groups of the synthesized h-K2W4O13 resulted in excellent adsorption performance for methylene blue.

© 2018 Elsevier Ltd Heavy metals often coexist in contaminated wastewater systems and their competitive behavior could affect the adsorption capacity of biochar. Till now, the competitive adsorption of heavy metals by biochar derived from anaerobically digested sludge has never been reported. In this work, biochar from anaerobically digested sludge was synthesized and characterized to explore the competitive behavior of widely co-existed Pb(II) and Cd(II). The mutual effects and inner mechanisms of their adsorption on studied biochar were systematically investigated via single-metal and binary-metals systems. In single-metal system, the biochar exhibited much higher adsorption capacity for Pb(II) compared to that for Cd(II). The maximum adsorption capacities of Pb(II) and Cd(II) based on single-component adsorption isotherm were 0.75 and 0.55 mmoL/g, respectively, which were much higher than those reported biochars from different materials. In binary-metals system, the Cd(II) adsorption on biochar was severely inhibited, while the uptake of Pb(II) was not affected significantly. The results of binary-components adsorption isotherm clearly demonstrated the competitive adsorption between two metals occurred as well as the preference of biochar for Pb(II) compared to Cd(II). FTIR and metal characteristics analysis results revealed that Pb(II) had exactly the same adsorption sites with Cd(II), but Pb(II) has a greater affinity than Cd(II), thereby exhibiting a competitive advantage in the coexisting system.

© 2015, eLife Sciences Publications Ltd. All rights reserved. A complex interplay of viral, host and ecological factors shape the spatio-temporal incidence and evolution of human inuenza viruses. Although considerable attention has been paid to inuenza A viruses, a lack of equivalent data means that an integrated evolutionary and epidemiological framework has until now not been available for inuenza B viruses, despite their significant disease burden. Through the analysis of over 900 full genomes from an epidemiological collection of more than 26,000 strains from Australia and New Zealand, we reveal fundamental differences in the phylodynamics of the two co-circulating lineages of inuenza B virus (Victoria and Yamagata), showing that their individual dynamics are determined by a complex relationship between virus transmission, age of infection and receptor binding preference. In sum, this work identifies new factors that are important determinants of inuenza B evolution and epidemiology.

Background: 18 500 laboratory-confirmed deaths caused by the 2009 pandemic influenza A H1N1 were reported worldwide for the period April, 2009, to August, 2010. This number is likely to be only a fraction of the true number of the deaths associated with 2009 pandemic influenza A H1N1. We aimed to estimate the global number of deaths during the first 12 months of virus circulation in each country. Methods: We calculated crude respiratory mortality rates associated with the 2009 pandemic influenza A H1N1 strain by age (0-17 years, 18-64 years, and >64 years) using the cumulative (12 months) virus-associated symptomatic attack rates from 12 countries and symptomatic case fatality ratios (sCFR) from five high-income countries. To adjust crude mortality rates for differences between countries in risk of death from influenza, we developed a respiratory mortality multiplier equal to the ratio of the median lower respiratory tract infection mortality rate in each WHO region mortality stratum to the median in countries with very low mortality. We calculated cardiovascular disease mortality rates associated with 2009 pandemic influenza A H1N1 infection with the ratio of excess deaths from cardiovascular and respiratory diseases during the pandemic in five countries and multiplied these values by the crude respiratory disease mortality rate associated with the virus. Respiratory and cardiovascular mortality rates associated with 2009 pandemic influenza A H1N1 were multiplied by age to calculate the number of associated deaths. Findings: We estimate that globally there were 201 200 respiratory deaths (range 105 700-395 600) with an additional 83 300 cardiovascular deaths (46 000-179 900) associated with 2009 pandemic influenza A H1N1. 80% of the respiratory and cardiovascular deaths were in people younger than 65 years and 51% occurred in southeast Asia and Africa. Interpretation: Our estimate of respiratory and cardiovascular mortality associated with the 2009 pandemic influenza A H1N1 was 15 times higher than reported laboratory-confirmed deaths. Although no estimates of sCFRs were available from Africa and southeast Asia, a disproportionate number of estimated pandemic deaths might have occurred in these regions. Therefore, efforts to prevent influenza need to effectively target these regions in future pandemics. Funding: None. © 2012 Elsevier Ltd.

The photocapacitance method was used to investigate the two donor states with optical ionization energies of 0.73 and 1.30 eV in Sn-doped Al x Ga 1-x As. Evidence is presented that both large-lattice-relaxation states are independent charge states and originate from different deep centers. The observation of phonons at about 10 meV accompanying the multiphonon processes in the photocapacitance transient implies that the atomic structures of the two deep centers are substitutional-interstitial in character