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A full‐scale wastewater treatment plant in China experienced unintentional anammox bacterial enrichment on biofilm carriers placed in the anaerobic and anoxic zones of an anaerobic/anoxic/oxic process under ambient temperatures and without bioaugmentation. Here, we show that microaerophilic conditions resulting from air scouring needed for biofilm carrier suspension in the anaerobic/anoxic zones can support a robust nitritation/anammox process. Results from an in situ on/off air scouring test showed that air scouring strongly induced both ammonia and total inorganic nitrogen removal in the anaerobic/anoxic zones. Ammonium concentration in the anaerobic and anoxic tanks remained constant or even slightly increased when air scouring was off, indicating that air scouring made a noticeable difference in nitrogen profiles in the anaerobic/anoxic zones. Various batch tests further indicated that partial denitrification is not likely to generate nitrite for anammox bacteria. Robust nitritation, and anammox on the carriers, can occur at low dissolved oxygen conditions, as measured in the full‐scale facility. The observations show that mainstream deammonification without sidestream bioaugmentation at moderate temperature is feasible and further optimization by a more dedicated design can result in improved nitrogen removal in cases when chemical oxygen demand is limited in mainstream wastewater treatment. Practitioner points: Microaerophilic conditions in a full‐scale IFAS reactor caused mainstream anammox in moderate temperate area.Robust nitritation, and anammox on the carriers, can occur at low dissolved oxygen conditions in anaerobic/anoxic tanks with air scouring.Anammox can function well with conventional nitrification and denitrification process at mainstream conditions for stable nitrogen removal. [ABSTRACT FROM AUTHOR]

Spontaneous anammox bacteria enrichment at mainstream conditions was reported in a full‐scale Wastewater Treatment Plant (WWTP) in a temperate zone of China. The mainstream anammox was observed after WWTP process retrofit, which constructed a hybrid sludge retention time (SRT) system by providing moving carriers in the anaerobic/anoxic tank and was initially designed to enhance the denitrification process in a conventional anaerobic/anoxic/oxic process. The hybrid SRT system achieved 86.0 ± 4.6% total nitrogen (TN) removal via combined mainstream anammox and conventional denitrification. Autotrophic denitrification via mainstream anammox was confirmed by various shreds of evidence including high‐throughput sequencing, specific anammox activity test, and 15N isotopic tracing. Long‐term anammox bacteria existence in the biofilm of the carrier in anoxic zones was detected in a much higher relative abundance compared with other spots. The contribution of anammox activity to TN removal was estimated at around 20%–30%. The reasons leading to spontaneous anammox enrichment were mainly attributed to the carriers for slow‐growing bacteria growth and dissolved oxygen gradient in the anoxic tank (caused by intermittent aeration) for nitrite production. The insights of this full‐scale case study provide important perspectives for future mainstream anammox application, and also the design of an energy‐neutral WWTP process. Practitioner points: Spontaneous mainstream anammox in a full‐scale WWTP after its retrofit in a temperate zone of China was reported.Anammox bacteria enrichment and long‐term stability on moving carriers at mainstream conditions was achieved by modified hybrid SRT system.The hybrid SRT system achieve stable nitrogen removal even in cold winter and high BOD/N situation by combining mainstream anammox with conventional denitrification.Long term full‐scale operation demonstrated excellent nitrogen removal with about 20%–30% contribution of mainstream anammox.This full‐scale case study provided perspectives for future optimizing mainstream anammox application, and also energy‐neutral WWTP process design. [ABSTRACT FROM AUTHOR]

A full-scale biofilm system using fluidized-carriers integrated with anaerobic-anoxic–aerobic process (treatment capacity of 3.75 × 10 5 m 3 d −1 ) was used for municipal wastewater treatment. The results indicated relatively higher removal efficiencies of 86% total nitrogen (TN), 97% ammonium (NH 4 -N) and 97% total phosphorus (TP) were achieved, with 0.32 mg L −1 TP, 0.81 mg L −1 NH 4 -N and 8.07 mg L −1 TN in the effluent, which meet the Class A of Discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002) of China. Microbial results indicated the dominant microorganisms in the suspended sludge were Proteobacteria and Bacteroidetes at phylum level and β -Proteobacter at class level. The dominant microorganism in the biofilm was Proteobacteria at phylum level, with γ-Proteobacter (17.5%), β -Proteobacter (14%) and δ-Proteobacter (13.08%) distributed at class levels. The presence of Proteobacteria and Bacteroidetes in this system may be related with the phosphorus removal. A reddish color biofilm was formed on the surface of fluidized-carriers in the anaerobic tank and showed specific anammox ability, this may be related with the dominance of 0.0278% Planctomycetaceae at family level and 0.0278% Planctomycetales at order level. Besides the denitrification effects, the possible anammox bacteria present in the anaerobic tank might have also contributed to high nitrogen removal efficiency. [ABSTRACT FROM AUTHOR]

A stable aqueous dispersion of hybrid silica nanocapsules encapsulating fluorescent conjugated polymers have been successfully synthesized viaa facile and highly benign approach of templated condensation of silica precursors at the core–corona interface of PEO-based block copolymer micelles. [ABSTRACT FROM AUTHOR]

Abstract: This study aims to investigate the therapeutic potential of adult bone marrow stromal cells (BMSCs). Exposed to a cocktail of induction medium, some BMSCs could differentiate into cell types with phenotypes of neural lineages in vitro. These cells expressed neural markers nestin, GFAP, 68-kDa neurofilament and β-tubulin III as detected by immunohistochemistry and RT-PCR. Fluorescence-labeled cells were injected intravenously at 72h after traumatic brain injury. Transplanted cells survived and migrated to the ipsilateral cerebral cortex at different time points after injection. They were immunopositive for neuronal marker MAP-2, oligodendrocyte marker CNPase, astrocytic maker GFAP or microglial marker OX-42 in vivo. In rats receiving BMSC transplants, there were significant improvements in motor and neurological functions when compared with the control groups. Hence, the therapeutic potential of BMSCs for traumatic brain injury is further amplified. [Copyright &y& Elsevier]