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Reliability of blades has a profound impact on both serviceability and safety of offshore wind turbines. Reliability estimation of wind turbine blade is a complex and time-consuming problem with multi-physics coupling and multi-failure modes correlation. Developing physics-of-failure modeling and reliability analysis methods with high efficiency and accuracy is a long-term challenge. In this work, a high availability and cost-effectiveness reliability estimation framework for offshore wind turbine blade by combining transfer learning (TL) and direct probability integral method (DPIM) is proposed. Extensive performance simulation of offshore wind turbine blade is a complex and necessary task, this paper develops a new adaptive sampling strategy to improve the validity of sample selection in the design space; On this basis, a physics-of-failure surrogate modeling approach is proposed by introducing TL method to fuse two kinds of multi-physics coupling analysis data, then the performance of all critical loads can be predicted efficiently in advance to provide a reliable design; Further, this paper provides an efficient reliability estimation method for offshore wind turbine blades by combining DPIM and surrogate model. Finally, the validity of the proposed approach is illustrated by numerical example and offshore wind turbine blade reliability estimation. The proposed framework provides a cost-effective alternative to higher loads simulation efforts and safety factors selection. • A new adaptive sampling strategy for multi-failure modeling is proposed. • A failure modeling method is developed for multi-physics coupling system. • A reliability estimation method is proposed based on Dirac delta function. [ABSTRACT FROM AUTHOR]

Tap water quality is at risk for odor-producing algae. Besides being hazardous to source water and water treatments, these algae threaten drinking water distribution system (DWDS). Yet little information is available for odorous risks occurring, responding, and transforming in real DWDS. Hence, two algae (Microcystis aeruginosa , MA; Pseudanabaena sp., PS) were selected for pilot studies. Two ways were verified for algal occurrence, including insufficient water treatments and DWDS-biofilm attachment. MA survived moderate disinfectant exposures and restored odorants (β-cyclocitral). Also, MA could be attached to biofilm and its detachment occurred upon flushing (0.60 m/s). These occurrence ways were not seen for PS. Three factors were compared for living algae in DWDS. Flow velocities had minimal impacts on MA but affected PS odorant (2-methylisobropanol, 2-MIB) releases. Releasing rates increased by 115.79% with velocity from 0.05 m/s to 1.50 m/s. Disinfectants were the riskiest, maximizing risks for MA and PS, respectively at 0.30 mg/L NH 2 Cl and 1.00 mg/L Cl 2. Coexisting antibiotics showed selective effects and reduced risks, e.g., tetracycline reduced MA intensity and PS odorant production. For naked odorant transformation, 2-MIB in DWDS had reduced degradation ratios compared to beaker conditions. Overall, odorous risks by MA and PS were different. MA was tough and could resist water treatments and adverse stressors in DWDS, with partial odorants remaining within cells. PS was vulnerable to treatments and DWDS, and the released odorants were not degradable. Hence, customized management is required for various algal odorous problems in DWDS. [Display omitted] • Viable algae entered pipes and formed odorous risks due to insufficient treatments. • Microcystis cells were attached to pipe-biofilm, while Pseudanabaena cells were not. • Flow rates did not affect Microcystis ' integrity, but caused Pseudanabaena 's rupture. • Pipe-biofilm influenced disinfectants and antibiotics working on algal behaviors. • Transforming patterns of 2-MIB differed in pipe and beaker conditions. [ABSTRACT FROM AUTHOR]

RA signaling tiers mitochondrial metabolism to Sertoli cell-mediated efferocytosis of apoptotic germ cells via a mechanism independent of the nuclear RA receptor (RAR) activity. [Display omitted] Efferocytosis of massive non-viable germ cells by Sertoli cells (SCs), the specialized phagocytes, is essential for maintaining testis homeostasis. What elusive is the contribution of mitochondrial metabolism to this energy-consuming process, as SC has a preference of aerobic glycolysis. All-trans retinoic acid (ATRA, hereafter referred to as RA) is a well-known morphogen that primarily acts through the nuclear RA receptor (RAR). It sustains SC blood-testis barrier integrity, and it's SC-derived RA sets the timing of meiotic commitment. In this study, we revisited RA in SC biology, from the perspective of SC-mediated efferocytosis. We provide evidence that RA induces transcriptional programming of multiple regulators involved in efferocytosis, which thereby represses SC-mediated efferocytosis, via a RAR-independent mechanism, as blocking pan-RAR activity fails to rescue RA-induced defective efferocytosis. RA-treated SCs exhibit alternations in mitochondrial dynamics and metabolism, and the hindered efferocytosis can be rescued by stimulating mitochondrial OXPHOS via pharmacological targeting of AMPK and PDK. We thus prefer to propose a signaling axis of RA-mitochondrial metabolism-efferocytosis. Our study uncovers a hitherto unappreciated role of RA in SC biology and tiers mitochondria metabolism to SC-mediated efferocytosis, contributing a deeper understanding of SC in male reproduction. [ABSTRACT FROM AUTHOR]

Due to the use of Cu(II) ions as catalysts, the production of polyacrylamide generates Cu-containing wastewater, constituting an environmental safety hazard and a waste of resources. This study proposes symmetric Ti 3 C 2 T x MXene-based electrodes for capacitive deionization to remove Cu(II) ions from chemical wastewater as a clean, low-energy, and resource-recyclable method and investigates their performances and mechanisms. Results showed that the adsorption capacity and removal efficiency of Cu(II) ions could reach 49.4 mg·g−1 and 98.6% under the optimal experimental conditions (the initial Cu(II) ions concentration was 100.0 mg·L−1, imposed voltage of 1.0 V, circulation velocity of 25.0 mL·min−1, and the initial pH of 4.0). At the same time, the adsorption capacity and removal efficiency of Cu(II) ions in real copper-containing wastewater were 47.4 mg·g−1 and 97.7%. In addition, by analyzing the changes of the electrode, the mechanism of electroadsorption was determined to include capacitive electroadsorption (double layer with pseudo-capacitance synergy) and cathodic electrodeposition. Ultimately, by applying a reverse voltage, Ti 3 C 2 T x MXene-based electrodes can be rapidly regenerated and recycled for continued use as catalysts. This simple operation has the advantage of potential economic benefits. Therefore, the Ti 3 C 2 T x MXene-based electrodes can be used potentially to remove Cu(II) ions in practical applications for environmental remediation. [Display omitted] • Ti 3 C 2 T x MXene-based electrode removed copper(II) ions efficiently. • Achieved 97.7% Cu(II) removal from real industrial wastewater. • Regenerated solutions achieve Cu(II) ions recovery as polyacrylamide catalyst. • The mechanism is EDL, pseudo-capacitance and electrodeposition. [ABSTRACT FROM AUTHOR]

Insufficient treatments during bloom-forming seasons allow algae to enter the subsequent drinking water distribution system (DWDS). Yet, scarce information is available regarding the role escaped algae to play in the DWDS, and how they interact with the system. Thus, three scenarios were conducted: a pilot DWDS with algae (a), pipe water (b), and pipe water with algae (c). Experimental results showed that, compared to biofilm and bulk water, escaped algae required fewer disinfectants. Competition for disinfectants varied with algal strains (Microcystis aeruginosa , MA; Pseudanabaena sp., PS) and disinfectant types (chlorine, Cl 2 ; chloriamine, NH 2 Cl). Algae in the MA-Cl 2 group showed the highest demand (6.25%–36.02%). However, the low-concentration disinfectants distributed to algae could trigger distinct algal status alternations. Cl 2 diffused into intact MA cells and reacted with intracellular compositions. Damaged PS cells reached 100% within 2 h. Typical disinfection byproducts (DBPs), including trihalomethanes (THMs), haloacetic acids and halogenated acetonitriles were examined. Disinfectant types and algal strains affected DBP yield and distribution. Although disinfectants consumed by algae might not promote dissolved DBP formation, especially for THMs. DBP formation of the other components was affected by escaped algae via changing disinfectant assignment (reduced by 45.45% for MA-Cl 2) and transformation efficiency (by 34.52%). The cytotoxicity risks were estimated. Dissolved DBP-induced risks were not added when escaped algae occurred, whereas disruption and release of intracellular substances increased risks; the maximum cytotoxicity did not occur at 12 h rather than at the end (24 h). Overall, this study provided an innovative perspective on algal-related water quality issues in water systems. [Display omitted] • Escaped algae had lower disinfectant demand than biofilm and bulk water. • Microcystis was intact even with chlorine entry, yet Pseudanabaena easily ruptured. • Algae impacted dissolved disinfection byproducts (DBPs) formation indirectly. • Chlorine diffusing into intact MA cells allowed extra DBP generation. • Algal entry in short-term (24 h) might not worsen pipe risks, yet algal rupture did. [ABSTRACT FROM AUTHOR]

Background: Progressive supranuclear palsy is a neuropathologically defined disease, and many studies worked on detecting the diagnostic use of Magnetic resonance imaging. This article purposed to detect the diagnostic performance of Magnetic resonance parkinsonism index (MRPI).Methods: We systematically searched electronic database PubMed for articles published since 1996 using the National Institute of Neurological Disorders and Stroke and Society for PSP (NINDS-SPSP) criteria as the diagnostic standard. Methodological quality was assessed by Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) and software Review Manager 5.3, software STATA 14.0 and meta-disc were applied in statistics analysis.Results: Totally 14 articles were included in this article. MRPI is proved to have pooled sensitivity of 0.98, pooled specificity of 0.99 in differentiating patients with Progressive supranuclear palsy (PSP) from patients with Parkinson's disease (PD) and the area under the Receiver operating characteristic curve value was 1.00.Conclusion: MRPI shows excellent performance in differentiating patients with PSP from patients with PD, the clinical usage of MRPI in auxiliary diagnosis of PSP is recommended. [ABSTRACT FROM AUTHOR]

Taste and odor (T & O) issues in drinking water have become serious problems which cannot be ignored by customers. Several studies have confirmed that microbes in water can biotransform halophenols (HPs) to haloanisoles (HAs) with earthy and musty flavors via microbial O -methylation. In this paper, the formation of 2-chloroanisole (2-CA), 2,4-dichloroanisole (2,4-DCA), 2,4,6-trichloroanisole (2,4,6-TCA), 2,3,6-trichloroanisole (2,3,6-TCA) and 2,4,6-tribromoanisole (2,4,6-TBA), and the microbial variation during the microbial O -methylation were investigated in annular reactors (ARs) with three coupon materials. For precursors, 42.5% of 2-CP and 68.9% of 2,4-DCP decayed during the reaction. Among the five HAs, the formation rate constant followed an order of 2,4,6-TCA > 2-CA > 2,4,6-TBA > 2,4-DCA ~ 2,3,6-TCA, while [HA] max followed a totally opposite one. The simulated flow velocity had no significant effect (p > 0.05) on HA formation. Ductile iron (DI) AR could produce more HAs than stainless steel (SS) and polyvinyl chloride (PVC) ARs. The final HA molar concentration followed an order of 2,3,6-TCA > 2,4-DCA > 2,4,6-TBA ~ 2,4,6-TCA > 2-CA, which might be explained by multiple factors including HP's dissociation degree, halogen atom's steric hindrance and specificity of HP O -methyltransferases. During the reaction, the microbial biomass dramatically increased 6.8–9.0 times in bulk water but dropped significantly on coupon biofilms. The effect of HPs significantly changed the bacterial communities on coupon in terms of composition and diversity, and declined the relative abundance of HA-producing bacteria, while fungi and their HA-producing genus showed better resistance ability towards HPs. By using Pearson correlation analysis, a significant correlation (p = 0.0003) was found between [HA] max and initial coupon biofilm biomass. Finally, a linear relationship was established between initial total biomass and HA formation potential. Unlabelled Image • Formation of five haloanisoles (HAs) was studied in annular reactors (ARs). • Ductile iron AR produced more HAs than stainless steel and polyvinyl chloride ARs. • 2,3,6-trichloroanisole had the largest yield among the five HAs. • Both biomass and coupon microbial communities shifted during the reaction. • A linear relationship existed between initial total biomass and [HA] max. [ABSTRACT FROM AUTHOR]

This paper investigates the Minimizing-Interference-for-Multiple-Paths (MIMP) problem for routing with minimum interference in wireless sensor networks, which is defined as: Given k routing requests { s 1 , t 1 } , ... , { s k , t k } , find k paths connecting these routing requests with minimum (wireless) interference. A key point to solve this problem is how to quantify interference level among multiple routing paths. However, all the existing metrics cannot measure interference precisely under some certain circumstances, e.g., some of the routing paths have common nodes or links. This paper proposes a metric that can measure interference precisely among any set of paths, even though these paths have some nodes or links in common. For this proposed metric, the MIMP problem is NP-hard even for k = 2. A heuristic Distributed On-line Algorithm for Minimizing Interference (DOAMI) is given to solve the MIMP problem. DOAMI has good communication and time complexity in theory, whose efficiency is also verified by simulation results. [ABSTRACT FROM AUTHOR]

Taste & odor (T&O) problems in drinking water are always complained by customers. Recent studies have indicated biofilms in drinking water distribution system (DWDS) are always ignored as potential sources of T&O compounds. In this paper, the formation of 2,4,6-trichloroanisole (2,4,6-TCA), one of the dominant T&O compounds, was investigated in a pilot-scale DWDS. The addition of precursor 2,4,6-trichlorophenol (2,4,6-TCP) of 0.2 mg/L induced the formation of 2,4,6-TCA with a maximum yield of ∼400 ng/L, and the formation kinetics can be described by a pseudo-first-order kinetic model. Effects of water distribution factors such as pipe material, temperature, flow velocity, and residual chlorine on the formation of 2,4,6-TCA were evaluated, and the pipe material was found to have the most remarkable effect. Ductile iron and stainless steel pipes produced much more 2,4,6-TCA than polyethylene (PE) pipe. The biofilm microbial communities on the three types of pipe walls were then comprehensively analyzed by heterotrophic plate count and 16S rRNA/ITS1 genes high throughput sequencing. The links between the 2,4,6-TCA formation potential and the microbial activity in genus and enzymatic levels in DWDS have been revealed for the first time. According to the characteristics of microbial assemblages of producing 2,4,6-TCA, quorum-sensing (QS) bacterial signaling system and extracellular DNA (eDNA) may be two promising targets for biofilm treatment and 2,4,6-TCA control in DWDS. [ABSTRACT FROM AUTHOR]

Peracetic acid (PAA) is a disinfection oxidant used in many industries including wastewater treatment. β -Lactams, a group of widely prescribed antibiotics, are frequently detected in wastewater effluents and surface waters. The reaction kinetics and transformation of seven β -lactams (cefalexin (CFX), cefadroxil (CFR), cefapirin (CFP), cephalothin (CFT), ampicillin (AMP), amoxicillin (AMX) and penicillin G (PG)) toward PAA were investigated to elucidate the behavior of β -lactams during PAA oxidation processes. The reaction follows second-order kinetics and is much faster at pH 5 and 7 than at pH 9 due to speciation of PAA. Reactivity to PAA follows the order of CFR ∼ CFX > AMP ∼ AMX > CFT ∼ CFP ∼ PG and is related to β -lactam's nucleophilicity. The thioether sulfur of β -lactams is attacked by PAA to generate sulfoxide products. Presence of the phenylglycinyl amino group on β -lactams can significantly influence electron distribution and the highest occupied molecular orbital (HOMO) location and energy in ways that enhance the reactivity to PAA. Reaction rate constants obtained in clean water matrix can be used to accurately model the decay of β -lactams by PAA in surface water matrix and only slightly overestimate the decay in wastewater matrix. Results of this study indicate that the oxidative transformation of β -lactams by PAA can be expected under appropriate wastewater treatment conditions. [ABSTRACT FROM AUTHOR]

Both excellent osteoinductivity and self-antibacterial performance are important for the successful clinical application of Ti-based metals as bone implant materials. Titania nanotube (TNT) arrays can endow Ti-based materials with multi-biofunctions due to the unique geometric structures of TNT that can be directly functionalized on the substrates through diverse techniques. In this work, strontium (Sr) and zinc oxides (ZnO) were doped into TNT arrays successively by hydrothermal treatment (HT) and subsequent atomic layer deposition (ALD). The super hydrophobic TNT array was obtained by grafting octadecylphosphonic acid (OPDA)-toluene. The results showed that the dual doping of Sr and ZnO together with super-hydrophobic property could not only enhance the osteoinductivity of Ti-based implants but also endow these implant materials with effective self-antibacterial ability. The former was ascribed to the osteogenic effects of Sr while the latter was contributed to the synergistic effects of ZnO and hydrophobic of OPDA. [ABSTRACT FROM AUTHOR]

To explore the mechanisms and influence factors on the production of 2,4,6-trichloroanisole (2,4,6-TCA) in surface waters, the 2,4,6-TCA formation potential (FP) test was conducted by incubating the real lake water with the addition of 2,4,6-trichlorophenol (2,4,6-TCP) precursor. Besides bacteria and fungi, two common cyanobacteria and algae species, i.e., Chlorella vulgaris and Anabaena flos-aquae , have been proved to have strong capabilities to produce 2,4,6-TCA, which may contribute the high 2,4,6-TCA FP (152.2 ng/L) of lake water. The microbial O-methylation of 2,4,6-TCP precursor is catalyzed by chlorophenol O -methyltransferases (CPOMTs), and their characteristics were identified by adding inductive methyl donors or excluding microorganisms via ultrafiltration. The results indicated both S -adenosyl methionine (SAM) dependent and non-SAM dependent CPOMTs played important roles; extracellular CPOMTs also participated in the biosynthesis of 2,4,6-TCA. Moreover, investigating the effects of various environmental factors revealed initial 2,4,6-TCP processor concentration, temperature, pH and some divalent metal cations (i.e., Mn 2+ , Mg 2+ and Zn 2+ ) had obvious effects on the production of 2,4,6-TCA. [ABSTRACT FROM AUTHOR]

Chloroanisoles are often reported as off-flavor compounds which produce an earthy and musty flavors and odors in drinking water. To improve understanding and ultimately minimize the formation of 2,4-dichloroanisole (2,4-DCA), 2,6-dichloroanisole (2,6-DCA) and 2,4,6-trichloroanisole (2,4,6-TCA), which have low odor threshold concentrations (OTC: 0.03–4 ng L −1 ), a kinetic database for the chlorination of anisole was established by kinetic measurements. The results showed that HOCl reacted with anisole in acidic solution, with the hydrogen ion as an important catalyst. Quantification of product distribution of the produced chloroanisoles demonstrated that a chlorine attack in the para-position was favored over the ortho-position. A kinetic model was formulated, which permitted investigation of the relative importance of the chlorine dose and other water quality parameters including the concentrations of anisole and several metal ions, as well as temperature, on the product distribution of chloroanisoles. In general, high chlorine doses led to low concentrations of intermediates. The presence of ions such as Fe 3+ and Al 3+ facilitated the formation of chloroanisoles, but Zn 2+ and Mn 2+ did not. The kinetic model can be applied to optimize water chlorination and minimize earthy and musty odors. [ABSTRACT FROM AUTHOR]

• Epanet combined with BP neural network was used to build a multi-parameter water quality model. • Complex chloric odor with chlorine and chloramines was considered. • Balancing chloric odor intensity and biosecurity in DWDS using Borg algorithm. • Chloric odor was firstly applied in real case to optimize chlorine dosage and sites. The traditional methods of increasing the chlorine disinfectant dosage in the drinking water distribution system (DWDS) to control microorganisms and improve the safety of drinking water quality are subjected to several challenges. One noticeable problem is the unpleasant odor generated by chlorine and chloramines. However, the generally proposed chlorine dosage optimization model ignores the chloric odor distribution in the DWDS. This study proposes a comprehensive multi-parameter water quality model and aims to balance the trade-offs between: (i) minimize the flavor profile analysis (FPA) degree of the chloric odor produced by chlorine and chloramines in the DWDS, and (ii) minimize the economic investment (chlorine dosage and operation cost). EPANET and back propagation (BP) network integrated with the Borg algorithm were employed as innovative approaches to simulate the chlorine, chloramines, and chloric odor intensity in the DWDS. Moreover, the application of the multi-parameter model was demonstrated in a real-world DWDS case study. 0.5 mg-Cl 2 /L (mg/L) chlorine at 8 secondary chlorination points was added to the DWDS as an optimized chlorine dosing scheme considering the olfactory and financial objective functions simultaneously. When switching to a superior water source, the FPA of the chloric odor in DWDS increased by a maximum of 1.4 at most if the initial chlorine dosage remained as before. To avoid the occurrence of chloric odor and also control the residual free chlorine (residual chlorine) at a suitable value, the initial and secondary chlorine dosages were optimized to 0.4 mg/L and 0.3 mg/L, respectively. Under this condition, the initial chlorine dosage was reduced by 50% compared to the original operation scheme in City J, China, the qualification rate of the residual chlorine reached 97.2%, basically consistent with that before water source switching, and the chloric odor intensity of the DWDS was controlled below FPA 3.4. [Display omitted] [ABSTRACT FROM AUTHOR]

Smtnl2 is an epithelial Smoothelin that binds to actin filaments and is crucial for epithelial morphogenesis. We examined the role of Smtnl2 in Sertoli cells, which undergo dynamic cytoskeleton reorganization to phagocytose apoptotic germ cells, a process known as efferocytosis. We observed Smtnl2 expression in primary mouse Sertoli cells and the 15P1 Sertoli cell line. Smtnl2 expression increased in 15P1 cells committing efferocytosis. Smtnl2-deficient Sertoli cells exhibited defective ability to engulf apoptotic germ cells and importantly, the phenomenon occurred in the setting of an unaffected maturation of phagosome. We demonstrated that Smtnl2 regulates the engulfment process through the function of branched actin nucleation protein ARP3, an actin assembly dictator. Intriguingly, a shift in glucose metabolism that restricts lactate production in Sertoli cells was induced upon Smtnl2 depletion, leading to the activation of downstream AMPK and AKT signaling. Using an in vivo RNAi approach, we found that silencing of Smtnl2 in testis triggers an obvious disruption in cytoskeleton architecture and blood-testis barrier integrity across seminiferous epithelium, causing the detachment of massive germ cells from their nest, as evidenced by their exfoliation into the lumen. Overall, our study identifies Smtnl2 as a determinant for Sertoli cells' functioning in supporting spermatogenesis. [Display omitted] • Smtnl2 is an actin filament-binding protein required for mouse Sertoli cells function. • RNA silencing of Smtnl2 in cultured Sertoli cells impairs efferocytosis and lactate biosynthesis. • Smtnl2 orchestrates actin assembly by recruitment of ARP3. • RNA inhibition of Smtnl2 in mouse testis disrupts spermatogenesis and the blood-testis barrier. [ABSTRACT FROM AUTHOR]

Production and characteristics of typical taste and odor (T&O) compounds by Microcystis aeruginosa were investigated. A few terpenoid chemicals, including 2-MIB, β-cyclocitral, and β-ionone, and a few sulfur compounds, such as dimethyl sulfide and dimethyl trisulfide, were detected. β-Cyclocitral and β-carotene concentrations were observed to be relevant to the growth phases of Microcystis . During the stable growth phase, 41–865 fg/cell of β-cyclocitral were found in the laboratory culture. β-Cyclocitral concentrations correlated closely with β-carotene concentrations, with the correlation coefficient R 2 = 0.96, as it is formed from the cleavage reaction of β-carotene. For dead cell cases, a high concentration of dimethyl trisulfide was detected at 3.48–6.37 fg/cell. Four T&O compounds, including β-cyclocitral, β-ionone, heptanal and dimethyl trisulfide, were tested and found to be able to inhibit and damage Microcystis cells to varying degrees. Among these chemicals, β-cyclocitral has the strongest ability to quickly rupture cells. [ABSTRACT FROM AUTHOR]

The remediation of water polluted by fluroquinolones antibiotics remains an important issue. Although zero-valent copper (ZVC) coupled with molecular oxygen can destruct refractory organic pollutants, the activation efficiency still needs to be further improved. In this study, the introduction of ascorbic acid (AA) in ZVC/air process maintained a high-concentration of Cu(Ⅰ), which can efficiently activate molecular oxygen to generate reactive oxygen species (ROSs). Superoxide radicals and hydroxyl radicals coexisted in nZVC/AA/air system. The former contributed to the yield of H 2 O 2 and also acted as a mediator for Cu(Ⅱ)/Cu(Ⅰ) redox cycles, the latter was the pivotal ROSs for ciprofloxacin (CIP) destruction. The CIP degradation decelerated through the addition of excessive nZVC and AA, and the optimum dosages of nZVC and AA were determined to be 0.2 g/L and 1 mM, respectively. The developed nZVC/AA/air process could efficiently operate in a relative broad pH range of 3.0–7.0, which was due to the fact that AA prevented the precipitation of copper ions in solution via forming stable chelates. The coexistence of Cl− severely retarded the CIP removal. According to the results of UPLC-MS/MS analysis and density functional theory calculations, the plausible degradation pathways including the decarboxylation, defluorination, hydroxylation and cleavage of C–C bond in piperazine ring were proposed. [Display omitted] • The introduction of AA in nZVC/air system greatly accelerated CIP degradation. • AA maintained a high-concentration of Cu(Ⅰ), which efficiently activated molecular oxygen to generate ROSs. • Hydroxyl radicals mainly contributed to CIP destruction, while superoxide radical functioned as the mediator for copper cycles. • Several key affecting factors including ZVC dosage, AA concentration, solution pH and chlorine were examined. • The transformation route of CIP in nZVC/AA/air system was put forward. [ABSTRACT FROM AUTHOR]

As a globally important artificial sweetener, sucralose (SUC) is a persistent emerging contaminant in global aquatic environments. This research comprehensively track the fate and transport of SUC throughout an urban water cycle; to perform laboratory experiments to determine chlorinated disinfection by-products (DBPs) of SUC sebsequent to advanced oxidation with ozone; and to perform a risk evaluation of SUC related DBPs.; The results demonstrated that SUC was consistently present throughout the urban water cycle, including consumer's tap water. The inluent to the municipal wastewater treatment plant contained 1033.4-2626.3 ng/L SUC, and as expected for this non-biodegradable artificial sweetener, the concentration in the effluent was slightly reduced to 917.6-2031.2 ng/L. The concentration of SUC varied in surface waters with a peak value of 2070.0 ng/L. In finished drinking water 288.1–505.3 ng/L SUC was found, and values of 177.7–409.7 ng/L were present in the distribution system. Up to 16.3% of SUC concentration discharged as municipal wastewater was delivered to residents in their drinking water. While conventional treatment little removed SUC, the mean removal efficiency of SUC with ozonation followed by activated carbon filtration was 39.6% at a full-scale drinking water treatment plant. The fate and transformation of SUC in drinking water treated by ozonation and chlorination were investigated in laboratory experiments. Ozonation partially degraded SUC; however, intermediates reacted with chlorine to generate DBPs, including trichloromethane (TCM), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA). Peak 7-days potential formation of TCM, DCAA and TCAA were 0.016, 0.51 and 23.34 μ g/mg SUC, respectively. DBP yields increased with increasing chlorine dosage, chlorination time, temperature, and solution pH. The presence of ammonia nitrogen in water facilitated dichloroacetonitrile (DCAN) production up to 0.78 μ g/mg SUC, while simultaneously reducing the yield of TCM, DCAA and TCAA. Human exposure analysis revealed that carcinogenic risks of DBPs caused only by SUC ozonation were in the range of 1.86 × 10−12-6.12 × 10−9, while non-carcinogenic risks were in the range of 6.0 × 10−9-4.37 × 10−6. The pervasive occurrence of SUC in an urban water cycle, couple to its resistance to biological and chemical treatment, confirms that SUC is a persistent contaminant in the aquatic system, including tap water. [Display omitted] • Sucralose occurs at hundreds ng/L in waters: sewage > surface water > tap water. • Ozonation transforms chlorine resistant sucralose to DBPs precursor. • TCAA is the major DBP generated by sucralose subsequent to ozonation. • Alkaline pH favors DBP formation from sucralose in treatment and distribution. [ABSTRACT FROM AUTHOR]

Delivering quality-changed water often contributes to the biological instability of drinking water distribution systems (DWDS). However, the potential effects of quality-changed water on the biostability within DWDS are not well understood, especially after water switching to quality-improved water. The objective of this study was to investigate the effects of quality-improved water on DWDS, focusing on the stability of biofilm. The practical aged-pipe was assembled into pipe reactors to simulate the effect of switching to quality-improve water. The adenosine triphosphate (ATP) concentration of bulk water in the pipe reactors increased from ∼1.2 ng/L to almost above 5 ng/L when fed water switching to TP 2. Biomass quantified by measuring ATP concentration confirmed that the risk of biofilm release through aged cast-iron (CI) pipe surfaces after water source switching. The changes in water characteristics due to quality-improved water source could cause bacteria release in DWDS at the initial period (at the first 7 days). However, the DWDS can establish the new stable phase after 42 days. Over time, biomass in the bulk water of the distribution system decreased significantly (The ATP concentration in the bulk maintains around 3 ng/L) after 42 days, indicating the improvement of water quality. The biofilm was dominated by bacteria related to iron-cycling process, and at the genus level, Desulfovibrio had the highest relative abundance, however, it decreased significantly (from 48% to 9.3%) after water source switching. And there was a slightly increase in the fraction of iron-oxidizing bacteria (IOB) and siderophore-producing bacteria (SPB), but a relatively higher increase in nitrate-reducing bacteria (NRB), nitrobacteria (NOB), and iron-reducing bacteria (IRB) was observed. Taken together, these results and the corrosion morphology, indicate that pipe biofilm and corrosion were chemically and microbially stable after re-stability under water source switching. In addition, the bulk water environment showed a marked decrease in selected bacteria at genus level, including pathogenic species, indicating the improvement of quality in drinking water. Image 1 • Biofilm detachment could be sensitively quantified by ATP measurement. • Pipe corrosion was stable after switching to low corrosive water. • Profile of microbial communities' alternation reveal the mechanism of biostability. • Less biomass and risk were found after switching to quality-improved water source. [ABSTRACT FROM AUTHOR]

• Eight bacteria from biofilms were identified and could produce haloanisoles. • Sphingomonadaceae was firstly proved to be able to O -methylate halophenols. • The halophenol O -methyltransferases of some bacteria were inducible. • Trihaloanisoles have higher potential risks than less substituted haloanisoles. • A new drinking water 2,4,6-trichlorophenol criteria was proposed. Microorganisms in drinking water distribution systems (DWDSs) can O -methylate toxic halophenols (HPs) into earthy-musty haloanisoles (HAs). However, the dominant HA-producing bacterial species and their O -methylation properties are still unknown. In this study, eight bacterial strains from DWDS were isolated and the community abundances of the related genera in bulk water and biofilms as well as their O -methylation properties were investigated. Among the genera discovered in this study, Sphingomonas and Pseudomonas are dominant and play important roles in DWDSs. All bacteria could simultaneously convert five HPs to the corresponding HAs. Two Sphingomonas ursincola strains mainly produced 2,3,6-trichloroanisole (2,3,6-TCA) (2.48 × 10-9−1.18 × 10-8 ng/CFU), 2,4,6-trichloroanisole (2,4,6-TCA) (8.12 × 10-10−3.11 × 10-9 ng/CFU) and 2,4,6-tribromoanisole (2,4,6-TBA) (2.95 × 10-9−3.21 × 10-9 ng/CFU), while two Pseudomonas moraviensis strains preferred to generate 2-monochloroanisole (2-MCA) (1.19 × 10-9−3.70 × 10-9 ng/CFU) and 2,4-dichloroanisole (2,4-DCA) (3.81 × 10-9−1.20 × 10-8 ng/CFU). Among the chloramphenicol-susceptible strains, four strains contained inducible O -methyltransferases (OMTs), while the O -methylations of the others were expressed constitutively. All bacteria could use S -adenosyl methionine as methyl donor. Potential taste and odor (T & O) risks of five HAs in DWDS followed an order of 2,4,6-TBA > 2,4,6-TCA > 2,3,6-TCA > 2,4-DCA > 2-MCA. The recommended 2,4,6-TCP criteria for T & O control is 0.003−0.07 mg/L. [ABSTRACT FROM AUTHOR]

• Degradation rate followed the order: 2,4,6-TBA>2-MCA>2,4-DCA>2,4,6-TCA. • OH and superoxide radical were involved in PAA/UV system. • The primary contribution: TBA (light radiation) and TCA (OH attacking). • The degradation pathway of haloanisoles in PAA/UV process were determined. • PAA/UV could largely reduce olfactory discomfort and health risk of haloanisoles. This study reported the kinetics and mechanism of degradation of odorant haloanisoles by peracetic acid combined with UV irradiation (PAA/UV). The removal efficiency of haloanisoles by PAA/UV was more than 92 % after 1 h reaction at pH 5, 25 °C, [HAs] =50 μg/L and [PAA] = 10 mg/L. The degradation of haloanisoles was fitted by the first-order kinetic model, and the rate constants of various haloanisoles followed the order: 2,4,6-tribromoanisole (2,4,6-TBA, (9.25 ± 0.71)×10−2 s-1) > 2-monochloroanisole (2-MCA, (8.00 ± 0.34)×10−2 s-1) > 2,4-dichloroanisole (2,4-DCA, (6.24 ± 0.55)×10−2 s-1) > 2,4,6-trichloroanisole (2,4,6-TCA, (5.05 ± 0.04)×10−2 s-1). The contribution of PAA (mainly composed of free radicals produced from PAA activation by UV) to the degradation rate of chloroanisoles in PAA/UV process ranged from 24 % to 36 %, while 25 % to the degradation rate of bromoanisole. Direct photolysis contributed much more to the removal of bromoanisole (42 %) than chloroanisoles (9–14 %). The inhibition of tert -butanol on degradation demonstrated the existence of ·OH, and superoxide radical and carbon-centered radicals were also probably existed in PAA/UV process. Combining density functional theory (DFT) calculation and products analysis, the degradation pathway of haloanisoles in PAA/UV process were determined. The odor and toxicity evaluation indicated PAA/UV process could reduce olfactory discomfort and health risk of haloanisoles. [ABSTRACT FROM AUTHOR]

Microcystis aeruginosa and Pseudanabaena are two common cyanobacterial species/genus and they can occur coincidently in many eutrophic lakes globally. These two cyanobacteria could produce Taste & Odor (T&O) compounds, and their production of T&O compounds might be changed when they are present coincidently. The amounts of T&O compounds and their producers may influence the effectiveness of water treatment processes. Therefore, the mutual interactions between Microcystis aeruginosa (FACHB-905, M) and Pseudanabaena sp. (FACHB-1277, P) on T&O compounds in co-cultures were evaluated in this study. Different initial cell concentrations of M and P, with ratios of M:P = 1:1, M:P = 1:2 and M:P = 2:1 were applied in the co-cultures. The growth of M was enhanced under all of the cyanobacterial cell ratios. The growth of P was enhanced under the ratio of M:P = 1:1, while it was inhibited under the ratios of M:P = 1:2 and M: P = 2:1. In addition, the growth of the two cyanobacteria and their production of β-cyclocitral and 2-methylisoborneol (2-MIB) in the filtrate of P were higher than those in the filtrate of M, which may be attributed to their associated secondary metabolites. The cell integrity and photosynthetic capacity of the two studied cyanobacteria are greatly affected by exposure to β-cyclocitral and 2-MIB. The results showed that β-cyclocitral and 2-MIB had the allelopathic effects on the two cyanobacteria species which might influence the composition of co-existing cyanobacteria and their production of T&O compounds. Image 1 • The growth of M. aeruginosa and associated β-cyclocitral is enhanced in co-cultures. • Allelopathy is crucial in the interspecific competition of co-existed cyanobacteria. • β-cyclocitral and 2-MIB could impact cyanobacterial growth and metabolism. [ABSTRACT FROM AUTHOR]

: The McDonald criteria are designed for predicting the second event in multiple sclerosis. With several revisions made to the McDonald criteria, the criteria get much easier to use, but what about the diagnostic validity? This research is conducted for evaluating the diagnostic validity of the McDonald criteria in multiple sclerosis. : Pubmed, Web of Science, Cochrane Library were systematically searched with keywords of "Multiple sclerosis" and "McDonald criteria" from, January 1st, 2010 to 27th, February 2020. The methodological quality of each study is assessed by Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). All of the statistics are analyzed by software STATA 12.0 and Meta-Disc 1.4. : Twenty articles are finally included according to the inclusion and exclusion criteria. Both the 2010 and 2017 McDonald criteria have excellent performance in predicting second events in multiple sclerosis. The 2017 McDonald criteria have better performance compared to the 2010 McDonald criteria (AUC, 0.83 vs 0.77). It is increased in sensitivity but decreased in specificity. : The McDonald criteria are useful in predicting second events in multiple sclerosis. The 2017 McDonald criteria have better performance than the 2010 McDonald criteria with increased sensitivity but decreased specificity. 1 This is the first meta-analysis on McDonald criteria and make comparison between 2010 and 2017 criteria. 2 We solve the current negotiation on diagnostic performance between 2010 and 2017 criteria, we conclude 2017 criteria to be better performed with increased sensitivity but decreased specificity. 3 We further detect reasons for reduced specificity, find DMT to be accountable and give recommendations to future researches. 4 We also find McDonald criteria have better performance in children rather than adults. [ABSTRACT FROM AUTHOR]

Ordered mesoporous Co 3 O 4 was fabricated using nanocasting route with SBA-15 or KIT-6 as the hard template and innovatively studied as the potential alternative to conventional Co 3 O 4 nanoparticles for peroxymonosulfate activation. The formation of spinel Co 3 O 4 was confirmed by wide-angle X-ray diffraction, fourier transform infrared, high resolution transmission electron microscopy and X-ray photoelectron spectroscopy, meanwhile the replication of ordered mesoporous structure was evidenced by low-angle X-ray diffraction, N 2 adsorption/desorption and transmission electron microscopy images. Among three different Co 3 O 4 catalysts tested, Co 3 O 4 -KIT6 displayed the best catalytic activity in PMS solution, achieving almost complete removal of 30 μM chloramphenicol within 60 min at the reaction conditions of 0.1 g L −1 catalyst and 1.0 mM peroxymonosulfate. The superior catalytic performance of Co 3 O 4 -KIT6 was ascribed to the combination of multiple unique characteristics, including the large specific surface area, high pore volume, high Co 2+ content and high density of surface active sites. Several factors played important roles in controlling the degradation of chloramphenicol. Higher catalyst dosage, higher PMS concentration, neutral pH and higher reaction temperature favored the removal. The balance among Co 2+ /Co 3+ , O 2− /O 2 and PMS decomposed in solution ensured the continuous generation of hydroxyl and sulfate radicals, and the latter made the predominant contribution for the CAP degradation. Considering its outstanding catalytic activity, excellent reusability and long-term stability, ordered mesoporous Co 3 O 4 should be an ideal catalyst for environmental application. [ABSTRACT FROM AUTHOR]

[Display omitted] • BM pretreatment changed physicochemical properties of digestive slurry and promoted release of VFAs, COD, and free water. • Excessive BM times (>60 min) and TS (>8%) are not recommended. • BM pretreatment shortened lag phase time (37.41–56.12%) and increased methane production (45.63–104.11%). • BM pretreatment improved rheological properties of digestive slurry and reduced stirring consumption during AD. • Energy analysis and energy conversion evaluation illustrates that BM pretreatment is a viable strategy. In this study, the effects of ball-milling (BM) pretreatment on the anaerobic digestion (AD) performance and energy conversion efficiency of corn straw (CS) were explored. The AD testing was conducted by varying BM times (0–120 min) and TS (4–10 %). The results showed that BM pretreatment increased microbial and enzyme accessibility to the CS and facilitated the hydrolytic acidification process of AD. The peak concentration of volatile fatty acids (VFAs) (5325.69 mg/L) and chemical oxygen demand (COD) (14524 mg/L) were increased, resulting in more substrates available for methanogenic bacteria. The lag phase time was shortened (37.41–56.12 %) and the cumulative methane production was increased (45.63–104.11 %). Accelerated rate of total ammonia nitrogen (TAN) release resulted in increased buffering capacity of the digestion system. Reduced the initial density of the digestive slurry (6.91–9.58 %) and altered the water distribution (maximum increase in free water content to 70.4 %), which facilitated the agitation of the AD process. Excessive BM times (>60 min) and TS (>8%) are not recommended. The BM60-6 presented the highest volatile solids (VS) removal (78.79 %), cellulose degradation (92.07 %) and biochemical methane potential (BMP) (309.69 mL/g VS). The BM pretreatment also improved the rheological characteristics of digestive slurry and reduced the stirring power consumption of the AD process. The BM60-6 showed the largest net energy benefit (28.2101 KJ/g VS) and net residual value (0.5000), and the high energy input of the pretreatment was balanced. This discovery breaks the conventional wisdom that mechanical pretreatment is meaningless because of higher power consumption. [ABSTRACT FROM AUTHOR]

Abstract Chlorination is essential to provide safe drinking water. However, this process leads to the formation of disinfection byproducts (DBPs). In this study, tryptophan (Trp) has been selected as a precursor to conduct the chlorine disinfection. Moreover, the factors that affect the formation of trihalomethanes (THMs) and iodinated trihalomethanes (I-THMs) are investigated. The formation pathway of Trp chlorination is proposed based on the intermediate products identified. According to the experimental results, the formation of THMs and I-THMs during Trp chlorination fitted a new first-order kinetic model. The dosage of chlorine, temperature, pH and the ratio of bromide and iodide had major influence on the formation of THMs and I-THMs during chlorination. In addition, the inhibition of luminescent bacteria Vibrio fischeri in the water sample increased during Trp chlorination. Highlights • The tryptophan (Trp) chlorination fitted a new first-order kinetic model. • The formation of trihalomethanes (THMs) and iodinated trihalomethanes (I-THMs) increased with the increase in temperature. • The toxicity of water sample during Trp chlorination was increasing. • Trp and chlorine reaction could open the ring of pyrrole and then were further halogenated to form THMs and I-THMs. [ABSTRACT FROM AUTHOR]

• Microbial O -methylation of diclofenac is firstly proved in drinking water. • A MPN method is established to quantify OMPPB in drinking water. • OMPPB risks are assessed in terms of odor, toxicity and bioaccumulation. • OMPPB community structure is shifted during drinking water treatment. • Mycobacterium and Pelomonas significantly influence the OMPFP profile. O -methylated pollutants (OMPs) are emerging contaminants in drinking water and mainly produced through bacterial O -methylation. However, the information of OMP-producing bacteria (OMPPB) in drinking water treatment plant (DWTP) is largely unknown so far. In this study, the OMPPB in water samples from three DWTPs (XL, JX and NX) were investigated by using cultivation-dependent and cultivation-independent technologies. Four OMPs were detected and their odor and toxicity risks were assessed. Formation potentials (FPs) of 2,4,6-trichloanisole, 2,3,6-trichloanisole, 2,4,6-tribromoanisole, pentachloroanisole and diclofenac methyl ester were determined in water samples and their values shifted significantly among DWTPs. A most probable number (MPN) method was established to quantify OMPPB numbers and the relationships between total haloanisole FPs (HAFPs) (y) and OMPPB numbers (x) in three DWTPs could be described by the following functions: y = 0.496×0.373 (XL), y = 0.041×0.465 (JX) and y = 0.218×0.237 (NX). Several genera like Bacillus, Ralstonia, Brevundimonas , etc. were newly found OMPPB among the cultivable bacteria, and their OMP products were evaluated in terms of quantity and environment risks (odor, toxicity and bioaccumulation). High-throughput sequencing revealed treatment process was the main driving factor to shape the OMPPB community structures and Mantel test showed HAFP profile was significantly influenced by Mycobacterium and Pelomonas. PICURSt2 analysis discovered four phenolic O -methyltransferases (OMTs) and four carboxylic OMTs which might be responsible for OMP formation. Several strategies were recommended to assess risk and control contamination brought by OMPPB in DWTPs. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Algae organic matters (AOM), including intracellular organic matters (IOM) and extracellular organic matters (EOM), are causing numerous water quality issues, among which formation of disinfection byproducts (DBPs) and odor & taste (O&T) compounds are of particular concern. In this study, physiochemical properties of IOM and EOM of Microcystic aeruginosa under an exponential growth phase (2.01 × 1011/L) were comprehensively characterized. Moreover, the yields of DBPs during AOM disinfection and O&T-causing compounds were quantified. Hydrophilic organic matters accounted for 86% and 63% of DOC in IOM and EOM, respectively. Molecular weight (MW) fractions of IOM in <1 kDa, 40–800 kDa, and >800 kDa were 27%, 42%, and 31% of DOC, respectively, while EOM primarily contained 1–100 kDa molecules. Besides, a low SUVA (0.84 L/mg m) and the specific fluorescence spectra suggested that AOM (especially IOM) was principally comprised of protein-like substances, instead of humic-like matters. The formation potentials of chloroform, chloroacetic acid, and nitrosodimethylamine were 21.46, 68.29 and 0.0096 μg/mg C for IOM, and 32.44, 54.58 and 0.0189 μg/mg C for EOM, respectively. Furthermore, the dominant O&T compound produced from EOM and IOM were 2-MIB (68.75 ng/mg C) and β-cyclocitral (367.59 ng/mg C), respectively. Of note, dimethyltrisulfide became the prevailing O & T compound following anaerobic cultivation. [Copyright &y& Elsevier]

Abstract: Poly-synchronous techniques were performed to investigate the inactivation and degradation mechanisms of Microcystic aeruginosa under UV-C irradiation and chlorination. Extracellular dissolved organic matter (EDOM) and intracellular dissolved organic matter (IDOM) properties were analyzed using excitation emission matrix (EEM) fluorescence spectroscopy, while the concentration of biochemical parameters including protein, phycocyanin, chlorophyll-a, and microcystin-LR was determined. Transmission electron microscopy was also used to obtained ultrastructural images. EEM analysis revealed that protein-like matters were the major EDOM fluorescence component, while amino acid-like and protein-like matters constituted IDOM with little amount of humic-like substances. In addition, the monitor of biochemical parameters showed that they had different susceptibility under the inactivation reactions. Poly-synchronous techniques confirmed that UV-C irradiation was more appropriate than chlorination for M. aeruginosa inactivation and degradation. The primary mechanism of UV-C irradiation was direct photo-degradation and indirect oxidation by reactive oxygen species, which effectively degraded the fluorescence EDOM and IDOM and caused decomposition of cytoplasmic inclusions and intracellular bioorganic substances. Different from UV-C, the inactivation during chlorination was due to the formation of HOCl, which permeated into the cyanobacteria cells and caused intracellular damage, accompanied with incomplete degradation of IDOM and harmful MC-LR. [Copyright &y& Elsevier]

• Fe(VI) oxidation induced death, apoptosis, and damage to algal cells. • Fe(VI) pre-oxidation inhibited the DBPs formation during chlorination of algae. • Less amounts of DBPs were generated at alkaline pH than at acidic pH. • Fe(VI) pre-oxidation generated insignificant amount of bromo-DBPs. • Halogenated DBPs were largely generated in subsequent chlorination. Algal organic matter (AOM) from seasonal algal blooms may be an important precursor of disinfection byproducts (DBPs) in drinking water. This paper presents the effect of ferrate(VI) treatment on two blue-green algae, Chlorella sp. and Pseudanabaena limnetica , in eutrophic water. The results demonstrated that Fe(VI) removed the algal cells by causing cell death, apoptosis, and lost integrity, and decreased AOM (in terms of total organic carbon) in water via oxidation and coagulation. Chlorination of the Fe(VI) pre-oxidized algal water samples generated halogenated DBPs (including trihalomethanes, haloacetic acids, haloketones, chloral hydrate, haloacetonitriles, and trichloronitromethane), but the concentrations of DBPs were lower than those formed in the chlorinated samples without pre-treatment by Fe(VI). Higher Fe(VI) dose, longer oxidation time, and alkaline pH were beneficial in controlling DBPs. In bromide-containing algal solutions, negligible amount of bromo-DBPs were generated in the Fe(VI) pre-oxidation, and halogenated DBPs were mainly formed in the subsequent chlorination. [ABSTRACT FROM AUTHOR]