Analyzing greenhouse gas emissions and influencing factors of 247 actual wastewater treatment plants in China using emission factor and operational data integrated methods (ODIM).

In response to China's policies on pollution control and carbon emission (CE) reductions, more stringent regulations have been implemented to evaluate CE in wastewater treatment facilities. In this study, we have analyzed CE from China's wastewater treatment plants (WWTPs) and influencing factor. Emission factor (EF) and operational data integrated methods (ODIM) were utilized to measure emissions, using data collected from 247 WWTPs over a 1-year period across seven regions in China. The average CE intensity was 0.45 kgCO2-eq/m3, affected by region, season, influent water quality, treatment processes, effluent discharge standards, and facilities. The scale effect was obvious only in the range of 2 × 105 m3/day. Underground WWTPs exhibited significantly higher CE compared to aboveground WWTPs. In summary, the assessment of CE in 247 actual WWTPs not only identifies emission reduction potential but also provides a scientific basis for formulating targeted emission reduction measures.

Integrating Olefin Carboamination and Hofmann-Löffler-Freytag Reaction by Radical Deconstruction of Hydrazonyl N-N Bond.

As a type of elementary organic compounds containing N-N single bond, hydrazone involved chemical conversions are extremely extensive, but they are mainly limited to N2-retention and N2-removal modes. We report herein an unprecedented protocol for the realization of division utilization of the N2-moiety of hydrazone by a radical facilitated N-N bond deconstruction strategy. This new conversion mode enables the successful combination of alkene carboamination and Hofmann-Löffler-Freytag reaction by the reaction of N-homoallyl mesitylenesulfonyl hydrazones with ethyl difluoroiodoacetate under photocatalytic redox neutral conditions. Mechanism studies reveal that the reaction undergoes a radical relay involving addition, crucial remote imino-N migration and H-atom transfer. Consequently, a series of structurally significant ϵ-N-sulphonamide-α,α-difluoro-γ-amino acid esters are efficiently produced via continuous C-C bond and dual C-N bonds forging.

Exploratory study on the metabolic similarity of denitrifying carbon sources.

Mixed carbon sources have been developed for denitrification to eliminate the "carbon dependency" problem of single carbon. The metabolic correlation between different carbon sources is significant as guidance for the development of novel mixed carbon sources. In this study, to explore the metabolic similarity of denitrifying carbon sources, we selected alcohols (methanol, ethanol, and glycerol) and saccharide carbon sources (glucose, sucrose, and starch). Batch denitrification experiments revealed that methanol-acclimated sludge improved the denitrification rate of both methanol (14.42 mg-N/gMLVSS*h) and ethanol (9.65 mg-N/gMLVSS*h), whereas ethanol-acclimated sludge improved the denitrification rate of both methanol (7.80 mg-N/gMLVSS*h) and ethanol (22.23 mg-N/gMLVSS*h). In addition, the glucose-acclimated sludge and sucrose-acclimated sludge possibly improved the denitrification rate of glucose and sucrose, and the glycerol-acclimated sludge improved the denitrification rate of volatile fatty acids (VFAs), alcohols, and saccharide carbon sources. Functional gene analysis revealed that methanol, ethanol, and glycerol exhibited active alcohol oxidation and glyoxylate metabolism, and glycerol, glucose, and sucrose exhibited active glycolysis metabolism. This indicated that the similarity in the denitrification metabolism of these carbon sources was based on functional gene similarity, and glycerol-acclimated sludge exhibited the most diverse metabolism, which ensured its good denitrification effect with other carbon sources.

Synergistic mechanisms between chlorine-mediated electrochemical advanced oxidation and ultraviolet light for ammonia removal.

The combination of chlorine-mediated electrochemical advanced oxidation (Cl-EAO) and ultraviolet (UV) radiation (UV-E/Cl) can efficiently remove ammonia from wastewater. However, the synergistic mechanisms between Cl-EAO and UV need to be explored in more detail. Thus, in this study, the ammonia oxidation performance of Cl-EAO and UV-E/Cl systems were compared, while the synergistic mechanisms were identified by the performance of UV/chlorine oxidation (UV-ClO) system and the results of electron paramagnetic resonance (EPR) analysis, free radical inhibition assays, and determination of steady-state concentration of free radicals. It was found that, compared with the Cl-EAO system, UV increased the ammonia removal rate by 42.85% and reduced the active chlorine concentration (56.64%) and nitrate yield (53.61%). In the Cl-EAO, and UV-E/Cl systems, Cl• were detected, and the free radical inhibition assays and determination of steady-state concentration of free radicals suggested that UV increased the concentration of Cl• by 51.47%, resulting in Cl• becoming the major contributor to ammonia oxidation in the UV-E/Cl system. Besides, UV also increase the concentrations of HO• and Cl2•-, which further promoted the organic matter removal in the real domestic wastewater. This study also discussed the ammonia oxidation performance of the UV-E/Cl system in real domestic wastewater, even with the presence of significant levels of organic and inorganic anions in the wastewater, UV increased the ammonia oxidation by 21.95%. The results of this study thus clarify the mechanisms and potential applications of UV-E/Cl technology.

The versatility of the putative transient receptor potential ion channels in regulating the calcium signaling in Aspergillus nidulans.

IMPORTANCE: Transient receptor potential (TRP) ion channels are evolutionarily conserved integral membrane proteins with non-selective ion permeability, and they are widely distributed in mammals and single-cell yeast and serve as crucial mediators of sensory signals. However, the relevant information concerning TRP channels in Aspergillus nidulans remains inadequately understood. In this study, by gene deletion, green fluorescent protein tagging, and cytosolic Ca2+ transient monitoring techniques, the biological functions of three potential TRP channels (TrpA, TrpB, and TrpC) have been explored for which they play distinct and multiple roles in hyphal growth, conidiation, responsiveness to external stress, and regulation of intracellular Ca2+ homeostasis. The findings of this study on the functions of potential TRP channels in A. nidulans may serve as a valuable reference for understanding the roles of TRP homologs in industrial or medical strains of Aspergillus, as well as in other filamentous fungi.

A new approach to optimizing aeration using XGB-Bi-LSTM via the online monitoring of oxygen transfer efficiency and oxygen uptake rate.

In wastewater treatment plants (WWTPs), aeration is vital for microbial oxygen needs. To achieve carbon neutrality, optimizing aeration for energy and emissions reduction is imperative. Machine learning (ML) is used in wastewater treatment to reveal complex rules in large data sets has become a trend. In this vein, the present paper proposes an aeration optimization approach based on the extreme gradient boosting-bidirectional long short-term memory (XGB-Bi-LSTM) model via the online monitoring of oxygen transfer efficiency (OTE) and oxygen uptake rate (OUR), thus allowing WWTPs to conserve energy and reduce indirect carbon emissions. The approach uses gain algorithm of XGB to calculate the importance of features and identify important parameters, and then uses Bi-LSTM to predict the target with important parameters as features. Operational data from a WWTP in Suzhou, China, is employed to train and test the approach, the performance of which is compared with ML models suitable for regression prediction tasks (XGB, random forest, light gradient boosting machine, gradient boosting and LSTM). Experimental results show the approach requires only a small number of input parameters to achieve good performance and outperforms other machine-learning models. When OTE and dissolved oxygen (DO) are used as features to predict the alpha factor (αF; since diffusers were used, multiply by the pollution factor F), the R-squared (R2) is 0.9977, the root mean square error (RMSE) is 0.0043, the mean absolute percentage error (MAPE) is 0.0069 and the median absolute error (MedAE) is 0.0032. When the predicted αF and the OUR are used as features to predict the air flow rate of an aeration unit, the R2 is 0.9901, the RMSE is 3.6150, the MAPE is 0.0209 and the MedAE is 1.5472. Using our optimized aeration approach, the energy consumption can be reduced by 23%.

Chlorine-mediated electrochemical advanced oxidation process for ammonia removal: Mechanisms, characteristics and expectation.

Chlorine-Mediated Electrochemical Advanced Oxidation (Cl-EAO) technology is a promising approach for ammonia removal from wastewater due to its numerous advantages, including small infrastructure, short processing time, easy operation, high security, and high nitrogen selectivity. This paper provides a review of the ammonia oxidation mechanisms, characteristics, and anticipated applications of Cl-EAO technology. The mechanisms of ammonia oxidation encompass breakpoint chlorination and chlorine radical oxidation, although the contributions of active chlorine, Cl, and ClO remain uncertain. This study critically examines the limitations of existing research and suggests that a combination of determining free radical concentration and simulating a kinetic model would help elucidate the contributions of active chlorine, Cl, and ClO to ammonia oxidation. Furthermore, this review comprehensively summarizes the characteristics of ammonia oxidation, including kinetic properties, influencing factors, products, and electrodes. The amalgamation of Cl-EAO technology with photocatalytic and concentration technologies has the potential to enhance ammonia oxidation efficiency. Future research should concentrate on clarifying the contributions of active chlorine, Cl, and ClO to ammonia oxidation, the production of chloramines and other byproducts, and the development of more efficient anodes for the Cl-EAO process. The main objective of this review is to enhance the understanding of the Cl-EAO process. The findings presented herein contribute to the advancement of Cl-EAO technology and provide a foundation for future studies in this field.

Performance and mechanism of phosphorus adsorption removal from wastewater by a Ce-Zr-Al composite adsorbent.

With the increasingly serious eutrophication of global water bodies and the strict discharge standards of tail water in wastewater treatment plants (WWTPs), there is an urgent technology need for efficient deep phosphorus removal from wastewater. A composite cerium-based adsorbent (Ce-Zr-Al) was synthesized by coprecipitation method for the adsorption of low concentration phosphorus in water. The performance of the Ce-Zr-Al composite adsorbent was explored, and the mechanism was also revealed through the analyses including SEM, BET, XPS, and FT-IR. The results showed that the composite adsorbent had excellent phosphorus removal performance. The phosphorus removal rate reached up to 92.6%, and the phosphorus concentration in effluent was less than 0.074 mg/L. The phosphate adsorption capacity of saturation was 73.51 mg/g. The adsorption process of phosphate was in accordance with pseudo-second-order kinetic model and Langmuir model. In addition, the composite adsorbent had a high zero potential point (pH PZC= 8) and a wide range of pH application. After the repeated desorption for 10 times in NaOH solution, the composite adsorbent still maintained good adsorbability (adsorption rate > 94%). The ligand exchange and electrostatic adsorption played the main role for the phosphorus removal from water using the composite adsorbent.

Pericytes protect rats and mice from sepsis-induced injuries by maintaining vascular reactivity and barrier function: implication of miRNAs and microvesicles.

BACKGROUND: Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis. We hypothesized that pericytes, a group of pluripotent cells that maintain vascular integrity and tension, are protective against sepsis via regulating vascular reactivity and permeability. METHODS: We conducted a series of in vivo experiments using wild-type (WT), platelet-derived growth factor receptor beta (PDGFR-ß)-Cre + mT/mG transgenic mice and Tie2-Cre + Cx43flox/flox mice to examine the relative contribution of pericytes in sepsis, either induced by cecal ligation and puncture (CLP) or lipopolysaccharide (LPS) challenge. In a separate set of experiments with Sprague-Dawley (SD) rats, pericytes were depleted using CP-673451, a selective PDGFR-ß inhibitor, at a dosage of 40 mg/(kg·d) for 7 consecutive days. Cultured pericytes, vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) were used for mechanistic investigations. The effects of pericytes and pericyte-derived microvesicles (PCMVs) and candidate miRNAs on vascular reactivity and barrier function were also examined. RESULTS: CLP and LPS induced severe injury/loss of pericytes, vascular hyporeactivity and leakage (P < 0.05). Transplantation with exogenous pericytes protected vascular reactivity and barrier function via microvessel colonization (P < 0.05). Cx43 knockout in either pericytes or VECs reduced pericyte colonization in microvessels (P < 0.05). Additionally, PCMVs transferred miR-145 and miR-132 to VSMCs and VECs, respectively, exerting a protective effect on vascular reactivity and barrier function after sepsis (P < 0.05). miR-145 primarily improved the contractile response of VSMCs by activating the sphingosine kinase 2 (Sphk2)/sphingosine-1-phosphate receptor (S1PR)1/phosphorylation of myosin light chain 20 pathway, whereas miR-132 effectively improved the barrier function of VECs by activating the Sphk2/S1PR2/zonula occludens-1 and vascular endothelial-cadherin pathways. CONCLUSIONS: Pericytes are protective against sepsis through regulating vascular reactivity and barrier function. Possible mechanisms include both direct colonization of microvasculature and secretion of PCMVs.

Effects of Liquid Viscosity on the Formation and Attenuation of Capillary Waves Induced by AC Electrowetting-on-Dielectric.

The capillary waves induced by electrowetting-on-dielectric have great potential in terms of capillary propulsion and other applications. At present, these applications are limited by a lack of research on the effects of liquid viscosity, which is an important parameter in controlling this phenomenon. This paper examines the formation, propagation, and attenuation of electrowetting-on-dielectric-induced capillary waves (EWCWs) on a liquid-free surface with different levels of liquid viscosity. The formation and propagation of the capillary waves are visualized using a high-speed camera and a free-surface synthetic Schlieren method. A theoretical model is established to describe the wave amplitude and wave propagation of EWCWs. The results show that the liquid viscosity, as well as the surface tension, significantly affects the formation and propagation of EWCWs. Using the results presented in this paper, a new type of Stokes viscometer based on EWCWs is proposed, enabling accurate measurements of liquid viscosity over a wide range of viscosity and temperature conditions.

Activated sludge process enabling highly efficient removal of heavy metal in wastewater.

Activated sludge process was a low-cost alternative method compared to the conventional physicochemical process for the treatment of heavy metal-containing wastewater. In the present study, the removal efficiency of Pb2+, Cu2+, and Ni2+ from wastewater by a sequencing batch reactor (SBR) activated sludge system was investigated, and the mechanism was revealed by static adsorption experiment of activated sludge. The results showed that the activated sludge in the SBR system was effective in removing Pb2+ and Cu2+ from wastewater at 10 mg·L-1 initial concentration, with a removal efficiency of 83.1 ~ 90.0% for Pb2+ and 74.3 ~ 80.6% for Cu2+, respectively. However, the removal efficiency for Ni2+ was only 0 ~ 6.2%. Static adsorption experiments showed that the adsorption capacity of activated sludge for three heavy metals was shown as Pb2+ > Cu2+ > Ni2+. When the initial concentration was 20 mg·L-1, the equilibrium adsorption capacity of activated sludge for Pb2+, Cu2+, and Ni2+ was 18.35 mg·g-1, 17.06 mg·g-1, and 8.37 mg·g-1, respectively. The main adsorption mechanisms for Pb2+ and Cu2+ were ligand exchange, electrostatic adsorption, and surface organic complexation processes, but Ni2+ removal mechanism mainly included electrostatic adsorption and surface organic complexation processes, showing that Ni2+ removal was inhibited in the presence of Pb2+ and Cu2+. The physicochemical properties and microbial diversity of activated sludge were greatly affected by the heavy metals in the SBR system, and genus Rhodobacter was found to be dominant bacteria enabling resistance to heavy metal ions.

Optimization on structure and operation parameters of biofilter for decentralized sewage treatment.

Aiming for treating decentralized domestic wastewater in rural China, this study evaluates the effects of ceramsite size and structure, and water recirculation parameters, upon the performance of recirculating biofilter (RBF). RBF shows stable capability of chemical oxygen demand (COD) remediation and ammonia nitrification. In addition, the microbial flora and structures of the various layers in the system are analyzed via high-throughput sequencing in order to study the microbial diversity. The results indicate that while the ceramic particle size has no significant influence on the COD remediation capacity, the ceramics with smaller particle sizes exhibit better ammonia nitrogen (NH4+-N) removal ability, with a first-order linear relationship between the influent ammonia nitrogen load and the effluent NH4+-N concentration in RBF (R2 > 0.64). An increased hydraulic load and intermittent operation are shown to deteriorate the water quality with respect to NH4+-N, while an increased recirculation ratio increases the removal rate of NH4+-N from the effluent. Further, the water distribution time has a stronger effect upon the NH4+-N concentration in the effluent than does the recirculation ratio. Moreover, the microbial structure of the multi-layer recirculating trickle biofilter varies significantly during the process. The results indicate that a high recirculation ratio, long water distribution time, and multi-layer structure will be beneficial for improving the pollutant treatment capacity of RBF.

Molecular mechanisms through which different carbon sources affect denitrification by Thauera linaloolentis: Electron generation, transfer, and competition.

Characterizing the molecular mechanism through which different carbon sources affect the denitrification process would provide a basis for the proper selection of carbon sources, thus avoiding excessive carbon source dosing and secondary pollution while also improving denitrification efficiency. Here, we selected Thauera linaloolentis as a model organism of denitrification, whose genomic information was elucidated by draft genome sequencing and KEGG annotations, to investigate the growth kinetics, denitrification performances and characteristics of metabolic pathways under diverse carbon source conditions. We reconstructed a metabolic network of Thauera linaloolentis based on genomic analysis to help develop a systematic method of researching electron pathways. Our findings indicated that carbon sources with simple metabolic pathways (e.g., ethanol and sodium acetate) promoted the reproduction of Thauera linaloolentis, and its maximum growth density reached OD600 = 0.36 and maximum specific growth rate reached 0.145 h-1. These carbon sources also accelerated the denitrification process without the accumulation of intermediates. Nitrate could be reduced completely under any carbon source condition; but in the "glucose group", the maximum accumulation of nitrite was 117.00 mg/L (1.51 times more than that in the "ethanol group", which was 77.41 mg/L), the maximum accumulation of nitric oxide was 363.02 µg/L (7.35 times more than that in the "ethanol group", which was 49.40 µg/L), and the maximum accumulation of nitrous oxide was 22.58 mg/L (26.56 times more than that in the "ethanol group", which was 0.85 mg/L). Molecular biological analyses demonstrated that diverse types of carbon sources directly induced different carbon metabolic activities, resulting in variations in electron generation efficiency. Furthermore, the activities of the electron transport system were positively correlated with different carbon metabolic activities. Finally, these differences were reflected in the phenomenon of electronic competition between denitrifying reductases. Thus we concluded that this was the main molecular mechanism through which the carbon source type affected the denitrification process. In brief, carbon sources with simple metabolic pathways induced higher efficiency of electron generation, transfer, and competition, which promoted rapid proliferation and complete denitrification; otherwise Thauera linaloolentis would grow slowly and intermediate products would accumulate seriously. Our study established a method to evaluate and optimize carbon source utilization efficiency based on confirmed molecular mechanisms.

Insights into the relationship between denitrification and organic carbon release of solid-phase denitrification systems: Mechanism and microbial characteristics.

Solid-phase denitrification is a promising alternative denitrification technology when facing a shortage of carbon sources. Nevertheless, it is still unclear whether there is a certain interaction between the denitrification process and the carbon release process in a solid-phase denitrification system. In this study, the concept of "Self-adaptation" was proposed for the relationship between denitrification and carbon release. At various influent nitrate loads, the PCL-supported denitrification system achieved an average nitrate removal rate of over 90.59 ± 7.01 % and a maximum denitrification rate of 0.67 ± 0.06 gN/(L·d). Microorganisms can spontaneously regulate the carbon release rate of PCL in response to changes in influent nitrate load, demonstrating "self-adaptation" of the PCL-supported solid-phase denitrification system. Regulation of carbon release rate via the "Self-adaptation" was achieved by changes in extracellular depolymerase activity. Acidovorax_sp. played a key role in "Self-adaptation", for its function of both denitrification and PCL degradation.

Revision surgery for symptomatic postoperative pseudocyst following full-endoscopic lumbar discectomy: clinical characteristics and surgical strategies.

BACKGROUND: A symptomatic postoperative pseudocyst (PP) is a cystic lesion that is formed in the operation area of the intervertebral disc, leading to worse symptoms. Some minority patients who developed PP experienced rapidly aggravating symptoms and could not be treated by any kind of conservative treatment. However, no clinical studies have evaluated the clinical characteristics and surgical strategies of symptomatic PP requiring a revision surgery after full-endoscopic lumbar discectomy (FELD). This study aimed to demonstrate the clinical characteristics and surgical strategies of symptomatic PP requiring a revision surgery after FELD. METHODS: We retrospectively analyzed the data of patients who received FELD revision surgeries due to symptomatic PP formation between January 2016 and December 2021. Common characteristics, time intervals of symptom recurrence and revision surgery, strategies for conservative treatment and revision surgery, operative time, imaging characteristics, numeric rating scale (NRS) score, Oswestry disability index (ODI) and overall outcome rating based on modified MacNab criteria were analyzed. RESULTS: Fourteen patients (males = 10, females = 4), with a mean age of 24.4 years, were enrolled. The mean time intervals of symptom recurrence and revision surgery were 43.5 and 18.9 days respectively. While the patients were conservatively managed with analgesics and physical therapy, pain persisted or progressively worsened. In comparison to the initial herniated disc, the PP was larger in 11 cases, and up- or down-migrated in four cases. The PP location included the lateral recess (n = 12), foraminal (n = 1), and centrolateral (n = 1) zones. One of the two cases treated by percutaneous aspiration (PA) was eventually treated by FELD as pain was not relieved. Follow-ups revealed an improved mean NRS score from 7.1 to 1.4, mean ODI from 68.6 to 7.9% and promising overall surgical outcomes. CONCLUSIONS: The progressively severe pain experienced due to PP might be a result of its enlargement or migration to the lateral recess and foraminal zones. As complete removal of capsule is the goal, we recommend FELD instead of PA.

Genome-wide association study reveals that GhTRL1 and GhPIN8 affect cotton root development.

KEY MESSAGE: Two regions located at chromosome A05 and D04 were found to be significantly associated with 0-0.5 mm and 0.5-2 mm diameter roots, respectively, and two candidate genes related to root development were identified. Roots absorb water and nutrients, and play an important role in plant growth. However, there are few genetic developmental studies on cotton root structural traits. In this study, we used 200 upland cotton (Gossypium hirsutum L.) varieties to analyze the phenotypic variation of 43 traits. A total of 2001 related single-nucleotide polymorphism (SNP) sites located within or near 1046 genes were detected through a genome-wide association study (GWAS). The 32 root traits were linked to SNPs that corresponded to 317 nonrepetitive genes. For SNPs associated with root length and 0-0.5 mm diameter root traits, a significant peak appeared on chromosome A05 (between 21.91 and 22.24 Mb). For SNPs associated with root surface area, root volume and 0.5-2 mm diameter root traits, a significant peak appeared on chromosome D04 (between 7.35 and 7.70 Mb). Within these two key regions, SNPs were detected in the promoter and coding regions of two candidate genes, GhTRL1-A05 and GhPIN8-D04. The expression levels of these two genes also changed significantly according to transcriptome sequencing and quantitative real-time PCR (qRT-PCR). After silencing the GhTRL1 and GhPIN8 genes via virus-induced gene silencing (VIGS), we found that the plants expressing TRV2::GhTRL1 and TRV2::GhPIN8 had a reduced root length, surface area. Moreover, the contents of cis-12-oxo-phytodienoic acid (cis-OPDA), isopentenyl adenosine (iPR) and cis-zeatin (cZ) in the roots of the plants expressing TRV2::GhTRL1 decreased. This study contributes to the cultivation and improvement of cotton varieties.

Analysis on common problems of the wastewater treatment industry in urban China.

The wastewater treatment industry in urban China generally faces certain common problems. To provide a comprehensive analysis on common problems of the wastewater treatment industry, survey data from 467 wastewater treatment plants (WWTPs) and field investigation reports of 38 WWTPs were analyzed. The research results showed that, the common problems of the wastewater treatment industry are mainly concentrated in WWTPs and the drainage system. The length of per capita drainage networks is insufficient, only 0.85 m; approximately 63.17% WWTPs have hydraulic load rates (HLRs) are greater than 80%, and the ratio of water quality between the design value and actual value is approximately 0.7; and there is still a considerable gap in construction of wastewater treatment facilities compared to those in developed countries. These are still major common problems perplexing the wastewater treatment industry in urban China. In this study, the common problems that hinder improving the operation efficiency of WWTPs were investigated, the causes of the discrepancy were analyzed, and three countermeasures, such as refinement design, optimization facilities and reasonable process control were jointly explored to solve them. This study may provide valuable insights and methods for the wastewater treatment industry to effectively address the discrepancy between the design and actual operation of WWTPs.

Regional discrepancy of microbial community structure in activated sludge system from Chinese WWTPs based on high-throughput 16S rDNA sequencing.

Overall understanding of microbial community structure in activated sludge (AS) system at regional level is of great significance for operation regulation of wastewater treatment plants (WWTPs). In this study, 110 AS samples from 21 cities in different Chinese regions were analyzed based on high-throughput 16S ribosomal DNA (rDNA) sequencing to explore effects of different regions on microbial community structure. Results showed that the regions with different characteristics (south and north, coastal and inland, high GDP and low GDP) had great impact on AS bacterial community in China. Core bacterial communities (101 OTUs) in south China were more abundant than those in north China (49 OTUs), and many core species in south China were associated with nutrient removal. Coastal WWTPs possessed unique bacterial communities due to the influence of marine bacteria. Phyla Chloroflexi and Acidobacteria were observed to be main biomarkers in coastal WWTPs. Compared with low GDP regions, more diverse microbial community and effective wastewater treatment were discovered in high GDP regions, and environmental factor analysis suggested that they were mainly correlated with high capacity and influent TP in the WWTPs. ß nearest taxon index (ßNTI) analysis showed that microbial community assembly in the analyzed AS samples was dominated by deterministic factors (70.67%) and influent quality was observed to be main factor.

Heavy metal-contained wastewater in China: Discharge, management and treatment.

A large amount of heavy metal-contained wastewater (HMW) was discharged during Chinese industry development, which has caused many environmental problems. This study reviewed discharge, management and treatment of HMW in China through collecting and analyzing data from China's official statistical yearbook, standards, technical specifications, government reports, case reports, and research paper. Results showed that industry wastewater discharged by an amount of about 221.6 × 108 t (in 2012), where emission of heavy metals including Pb, Hg, Cd, Cr(VI), T-Cr was around 388.4 t (in 2012). Heavy metal emission with wastewater in east China and central south China was observed to be graver than that in other areas. However, control of heavy metals in Pb and Cd in northwest China was more difficult compared with other areas. In terms of management, China's government has issued many wastewater discharge standards, strict management policies for controlling HMW discharge in recent years, resulting in reduced HMW discharge. In addition, main HMW treatment technology in China was chemical precipitation, and other technologies such as membrane separation, adsorption, ion exchange, electrochemical and biological methods were also occasionally applied. In the future, chemical industries will be concentrated in northwest China, therefore control of HMW discharge should be paid much more attention in those areas. In addition, more effective and environment-friendly heavy metal removal and regeneration technologies should be developed, such as biomaterials adsorbent.

A Transient Receptor Potential-like Calcium Ion Channel in the Filamentous Fungus Aspergillus nidulans.

Transient Receptor Potential (TRP) proteins constitute a superfamily that encodes transmembrane ion channels with highly diverse permeation and gating properties. Filamentous fungi possess putative TRP channel-encoded genes, but their functions remain elusive. Here, we report that a putative TRP-like calcium channel, trpR, in the filamentous fungus Aspergillus nidulans, performs important roles in conidiation and in adapting to cell wall disruption reagents in a high temperature-induced defect-dependent manner, especially under a calcium-limited culture condition. The genetic and functional relationship between TrpR and the previously identified high-affinity calcium channels CchA/MidA indicates that TrpR has an opposite response to CchA/MidA when reacting to cell wall disruption reagents and in regulating calcium transients. However, a considerable addition of calcium can rescue all the defects that occur in TrpR and CchA/MidA, meaning that calcium is able to bypass the necessary requirement. Nevertheless, the colocalization at the membrane of the Golgi for TrpR and the P-type Golgi Ca2+ ATPase PmrA suggests two channels that may work as ion transporters, transferring Ca2+ from the cytosol into the Golgi apparatus and maintaining cellular calcium homeostasis. Therefore, combined with data for the trpR deletion mutant revealing abnormal cell wall structures, TrpR works as a Golgi membrane calcium ion channel that involves cell wall integration.