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Stormwater reuse is one of the most important ways to mitigate water resource shortage. However, urban stormwater contains many bacteria species, which threaten the reuse safety. Therefore, stormwater disinfection is highly needed. Although disinfection has been widely conducted in the drinking water and reclaimed water, it is rarely carried out for stormwater. This study collected the roof stormwater and undertook chlorination disinfection. Two typical bacteria, Escherichia coli (E. coli) and Staphylococcus aureus (S.aureus) were selected in this study to investigate the disinfection efficiency. It is found that bacteria species present in the stormwater had an important influence on disinfection efficiency while the original stormwater quality did not show an obvious affect. However, when the disinfected stormwater was stored, the stormwater quality was highly variable during its storage process and the variability was affected by bacteria species. The S.aureus containing stormwater showed a high variability of quality and S.aureus significantly regrew. However, the E.coli containing stormwater quality had a relatively low variability and E.coli did not significantly regrew. Additionally, it is noted that after storage, the dissolved form of stormwater was more positive to the freshwater algae's growth while the particulate form (including bacteria and other particulate matters) was less. This implies that a further treatment such as filtration is needed before the stored stormwater is recharged into receiving waters in order to remove particulate forms. These research outcomes can provide useful insight to effective stormwater disinfection and ensure reuse safety.

Cell traction mediates the biochemical and mechanical interactions between the cell and its extracellular matrix (ECM). Traction force microscopy (TFM) is a powerful technique for quantitative cellular scale traction analysis. However, it is challenging to characterize macromolecular scale traction events with current TFM due to the limited sampling density and algorithmic precision. In this article, we introduce a super-resolution TFM by utilizing a novel substrate surface modification method. Our TFM technique achieved a spatial resolution comparable to fluorescence microscopy and precision comparable to the rupture force of an integrin-ligand bond. Correlated imaging of TFM with fluorescence microscopy demonstrated that the residing paxillin highly correlated with traction while α5 integrin was located differently. Time-lapse TFM imaging captured a transient traction variation as the adhesion protein passed by. Thus, the novel super-resolution TFM benefits the studies on cellular biochemical and mechanical interactions.

When deploying network nodes, there are many redundant nodes, low network coverage and high energy consumption of network nodes, the node deployment method of wireless sensor networks(WSN) based on mobile edge computing is studied. WSN nodes are divided into anchor nodes and unknown nodes. Taking the location information of anchor nodes as a reference, the specific location of unknown nodes is obtained by trilateral measurement. Minimizing the node distance error is taken as the objective function, and the cuckoo search algorithm is used to solve it to obtain the final location result of the node. The mobile edge computing method is used to design the node deployment method of WSN to complete the node deployment. Simulation results show that the number of redundant nodes in this method is 3, maximum network coverage is 89%, maximum energy consumption of network nodes is 34.3J.

Calcium and manganese are common ions that pollute drinking water and, therefore, ingestion may seriously harm human health. However, despite its importance, few studies into the synergistic removal of calcium and manganese have been reported. Calcium and manganese have similar chemical properties and, consequently, can be removed by co-crystallization, as the exact crystalline phase formed by this process and the process rate depend on the pH, the dissolved oxygen (DO) content, and the concentrations of the component ions. In this work, we experimentally studied the co-crystallization of Mn and Ca using an automatic potentiometric titrator. We found that the concentration of Mn

Expansion Microscopy (ExM) revolutionized the field of super-resolution microscopy by allowing for subdiffraction resolution fluorescence imaging on standard fluorescence microscopes. However, it has been found that it is hard to visualize actin filaments efficiently using ExM. To improve actin imaging, multifunctional molecules have been designed, however, with moderate success. Here, we present optimized methods for phalloidin conjugate grafting that have high efficiency for both cellular and tissue samples. Our optimized strategy improves anchoring and signal retention by ∼10 times. We demonstrate the potential of trifunctional linkers (TRITON) for actin imaging in combination with immunolabeling using different ExM protocols. 10x ExM of actin labeled with TRITON enabled us to visualize the periodicity of actin rings in cultured hippocampal neurons and brain slices by Airyscan confocal microscopy. Thus, TRITON linkers provide an efficient grafting method, especially in cases where the concentration of target-bound monomers is insufficient for high-quality ExM.

Purpose The goal of this study was to develop an imaging probe—IRDye-680RD-OX40 mAb—that can be used for noninvasive imaging and optical imaging of rheumatoid arthritis (RA). OX40/OX40 ligand (OX40L) interactions have been shown to exert potent costimulatory effects on T cell activation. Detectable change in T cell activation profiles was observed in early RA. Methods OX40 expression pattern was analyzed by flow cytometry. N-hydroxysuccinimide (NHS) esters are used to label proteins selectively on free amino groups of OX40 monoclonal antibody (mAb). Characterization of IRDye-680RD-OX40 mAb was measured and a fluorescence spectrum gathered. Cell binding assay was also performed between activated and naïve murine T cells. Longitudinal near-infrared fluorescence (NIRF) imaging of the probe was performed on day 8, day 9, day 10, and day 11 of adjuvant-induced arthritis (AIA) mouse model. Paw thickness and body weight were compared between the OX40 mAb and IgG injection groups. Results NIRF imaging with IRDye-680RD-OX40 mAb revealed strong OX40-positive responses with high specificity. Flow analysis showed that OX40 was specifically expressed on the surface of T cells in RP and spleen of AIA model. The AIA group was significantly differentiated from the control group at all time points with imaging monitoring. The region of interest (ROI) was in line with ex vivo imaging and biodistribution study. This study highlights the potential utility of the OX40 NIRF imaging as a new strategy for RA prediction and T cell monitoring. Conclusion The results provide evidence that IRDye-680RD-OX40 mAb detects organized T cells activation in early RA. The optical probe was capable of detection of RA pathogenesis. It identified transcriptional responses to RA that mediate its immune functions. Thus, it may be an ideal probe for RA imaging. Graphical Abstract

The security of the transmission line corridor is an important guarantee for the sustainable supply of electricity and an important prerequisite for the rapid development of the economy. Transmission corridors located in high mountains and valleys are often threatened by geological disasters, which seriously affect their stable operation. The main idea of this research is to explore a landslide in the Kunming transmission corridor in November 2021 and analyze its reason. In this study, we investigated the landslide in Kunming using 79 Sentinel-1A Synthetic Aperture Radar (SAR) images acquired from July 2020 to October 2021 (40 ascending images and 39 descending images) with sequential Interferometric Synthetic Aperture Radar (InSAR) methods. Then, the deformation changes before the landslide were analyzed in many ways. Influencing factors (i.e. precipitation, formation lithology, and vegetation coverage) indicated a high correlation between landslide locations and those of the study region. Seasonal variations in deformation were related to precipitation. The landslide in the Kunming transmission line corridor was mainly attributed to precipitation, carbonate karstification, and vegetation coverage. Finally, the correlation between deformation changes before the landslide and influencing factors in the Kunming transmission line corridor were determined.

Residual aluminium from the coagulation-sedimentation process in the treatment of surface water can decrease the catalytic activity of a manganese co-oxide filter film (MeOx) used for ammonium and manganese removal. To solve this problem, a MeOx filter was used as a pretreatment process to filtrate source water directly before the coagulation and sedimentation treatment. The removal performance and the mechanism of change in the activity of MeOx were investigated. The experimental results indicated that the MeOx filter removed ammonium and manganese from surface water sources effectively, and its manganese removal activity was enhanced. The characteristics of MeOx were investigated via SEM, EDS, XPS, and the BET surface area. Analysis of the experimental results showed that the increase in the content of Al under this condition was much lower than that under treatment with the coagulation-sedimentation process. After long-term operation, the amount and surface area of MeOx coated on the filter sand increased significantly, leading to an increase in the catalytic activity. However, in cold water, the catalytic activity of MeOx decreased, and more Mn(II) was obtained on the surface of MeOx. Thus, the morphology of MeOx changed. Fortunately, when water temperature increases, the removal activity can recover immediately. By inactivating microorganisms and comparing the removal performance with that under other conditions, the MeOx activity of the pretreatment process is preserved effectively and no strengthening measures are required. This study will provide a new strategy for the use of the MeOx catalytic technology.

Filamentous fungi can enter drinking water supply systems in various ways, and exist in suspended or sessile states which threatens the health of individuals by posing a high risk of invasive infections. In this study, the biofilms formation kinetics of the three genera of fungal spores, Aspergillus niger (A. niger), Penicillium polonicum (P. polonicum) and Trichoderma harzianum (T. harzianum) isolated from the groundwater were reported, as well as the effects of water quality parameters were evaluated. In addition, the efficiency of low- concentrations of chlorine-based disinfectants (chlorine, chlorine dioxide and chloramine) on controlling the formation of fungal biofilms was assessed. The results showed that the biofilms formation of the three genera of fungi could be divided into the following four phases: induction, exponential, stationary and sloughing off. The optimum conditions for fungal biofilms formation were found to be neutral or weakly acidic at 28 °C with rich nutrition. In fact, A. niger, P. polonicum, and T. harzianum were not observed to form mature biofilms in actual groundwater within 120 hr. Carbon was found to have the maximum effect on the fungal biofilms formation in actual groundwater, followed by nitrogen and phosphorus. The resistance of fungal species to disinfectants during the formation of biofilms decreased in the order: A. niger > T. harzianum > P. polonicum. Chlorine dioxide was observed to control the biofilms formation with maximum efficiency, followed by chlorine and chloramine. Consequently, the results of this study will provide a beneficial understanding for the formation and control of fungal biofilms.

Metalimnetic oxygen minima has been reported in many lakes and reservoirs, but the double metalimnetic oxygen minima (DMOM) is so far poorly understood. In this work, we first reported DMOM in the Sanhekou Reservoir, and investigated its formation reason and influence on the bacterial community composition (BCC). The results showed that the two anaerobic layers were formed in DMOM, located at 10 m and 45 m approximately. The rapid water storage process and thermal stratification resulted in the double metalimnions. Algal accumulation, decomposition and oxygen consumption in these regions during the sedimentation process eventually leaded to the formation of DMOM. Water temperature and DO gradients made outstanding contributions to the spatiotemporal environmental heterogeneity and significantly affected the BCC. Depending on the distribution of dissolved oxygen (DO), the storage process could be divided into three periods: DMOM, single MOM period and mixed period. Exiguobacterium and Ralstonia were dominated in DMOM due to the soil discharge and plant decomposition. Besides, BCC presented the largest vertical difference in DMOM and existed the interlayer-similar phenomenon (BCC in the two anaerobic layers were more similar). This study explained the formation of DMOM and its influence on BCC, which was helpful to understand the response of BCC to the storage process and unique DO structure in a moderate eutrophication reservoir.

Recently, the contamination of fungi in water has aroused widespread concern, which will pose a threat to water quality and safety, and raise diseases risk in the immunocompromised individuals. In this review, the characteristics and different physiological state of fungi in water are summarized. A comprehensive evaluation of the control efficiency and mechanism of waterborne fungi by the commonly used disinfection methods is provided as well. During the disinfection processes of chlorine (Cl

Long-distance water transfer projects are important for water allocation. To enhance our understanding of biofilm growth and changes in water quality during raw water transfer, raw water through a long-distance non-full culvert at flow rates of 1.4−2.0 m/s was studied. The results revealed that: (1) the biofilm total cell count (TCC) and heterotrophic plate count (HPC) were the highest at a flow rate of 1.5 m/s, which were 3.7 × 104 cells/cm2 and 1.1 × 103 CFU/cm2, respectively; (2) Proteobacteria had the highest relative abundance (RA) among all samples, and the RA in biofilm (78.85%) was higher than that in water (48%−59%); (3) when the pollutants and biofilm were partially shed, the total phosphorus (TP), permanganate index (CODMn), and dissolved organic carbon (DOC) increased by 0.011, 0.36, and 0.5 mg/L at most, respectively; and (4) dissolved oxygen (DO) was sufficient during non-full flow water transport and nitrification occurred. The highest removal rates of ammonium nitrogen (NH+4-N) and nitrous nitrogen (-N) reached 27.16% and 66.76%, respectively. At the flow rates of 2.0 m/s, the efficiency decreased to 10.47% and 41.25%, respectively, due to the shedding of biofilm. HIGHLIGHTS Raw water flow over a long-distance non-full culvert studied using an experimental model.; Flow rate influenced biofilm biomass, and resulted in different bacterial community structure in bulk water and biofilm.; Nitrification in the long-distance non-full culvert was only 0.54%–1.2% that in the simulation experiment.

Expansion microscopy (ExM) has been widely used to detect biomolecules in cultured cells and tissue samples due to its enablement of super resolution imaging with conventional microscopes, via physical expansion of samples. However, reaction conditions inherent to the process bring about strong fluorescent signal loss during polymerization and digestion and thus limit the brightness of the signal obtained post expansion. Here, we explore the impact of stabilizer-containing organic fluorophores in ExM, as a mitigation strategy for this radical-induced dye degradation. Through direct conjugation of 4-nitrophenylalanine (NPA) to our previously developed trifunctional reagents, we validate and demonstrate that these multifunctional linkers enable visualization of different organelles with improved fluorescent intensity, owning to protection of the dyes to radical induced degradation as well as to photoprotection upon imaging. At this point, we cannot disentangle the relative contribution of both mechanisms. Furthermore, we report anchoring linkers that allow straightforward application of NPA or Trolox to commercially available fluorophore-conjugated antibodies. We show that these anchoring linkers enable complete retention of biological targets while increasing fluorophore photostability. Our results provide guidance in exploring these stabilizer-modified agents in ExM and methods for increased signal survival through the polymerization steps of the ExM protocols. ispartof: CHEMISTRY-A EUROPEAN JOURNAL vol:28 issue:66 ispartof: location:Germany status: published

Waterborne fungi pose a potential threat to water supply safety due to their high resistance to disinfectants. Peracetic acid, as a promising alternative disinfectant to chlorine, has attracted increasing attention in water treatment. In this study, the inactivation of two dominant fungal species (Aspergillus niger and Aspergillus flavus) by sequential application of peracetic acid and ultraviolet (PAA-UV/PAA) was reported for the first time. Results revealed that the pre-exposure of PAA could facilitate the subsequent process of UV/PAA combination and shorten the lag phase in fungi inactivation. After 10 min of PAA pre-exposure, PAA-UV/PAA achieved 3.03 and 2.40 log inactivation of Aspergillus niger and Aspergillus flavus, which were 2- and 4.3-fold higher than that of direct UV/PAA under the same UV and PAA doses. PAA-UV/PAA disinfection also exhibited a stronger regrowth inhibition for incompletely inactivated fungal spores than direct UV/PAA. The increase of pH (5.0-9.0) and humic acid concentration (1.0-5.0 mg L

Pre-ozonation is an effective pretreatment tactic for mitigating fouling of ultrafiltration (UF) membrane in water and wastewater treatment, but the compatibility of polymeric UF membranes with residual ozone remains unclear. In this study, effects of long-term ozone exposure on properties and performance of polyvinylidene fluoride (PVDF) UF membrane reinforced by polyethylene terephthalate (PET) layer were systematically investigated. The exposure intensities were designed to simulate ozone exposure at 0.1 mg/L for 0.5-5 years. Chemical composition analysis suggested that the hydrophilic additives, such as possibly polyvinyl pyrrolidone (PVP), was gradually degraded and released from the membrane, whereas the PVDF matrix exhibited fairly good ozone resistance. Ozonation resulted in increase of pore size and decrease of surface hydrophilicity, which can be attributed to oxidation and dislodgement of hydrophilic additives. Accordingly, long-term ozonation led to moderate changes in performance factors, including increase of membrane permeability by 34%, decrease of retention ability by 21.8%, increase of organic fouling propensity. It is worth noting that membrane tensile strength suffered substantial decrease after ozonation, probably due to ozonation of the PET support layer. Overall, it seems that the PVDF functional layer exhibited good ozone resistance, but the PET support layer was the Achilles' heel of the reinforced PVDF membrane for integrating with pre-ozonation.

Melanin is a critical component of fungal cell wall which protect fungi from adverse environmental tress. However, the role of melanin for fungi during the disinfection with chlorine-based disinfectants has not been elucidated. The results showed that the inactivation rate constants of Aspergillus niger with chlorine and chlorine dioxide decreased from 0.08 to 2.10 min

The unstable interfaces between a SnO2 anode and an electrolyte in a Li-ion battery dramatically impair the reversibility and cycling stability of lithiation and delithiation, resulting in low roundtrip Coulombic efficiency (CE) and fast capacity decay of SnO2-based anode materials. Herein, a simple strategy of modifying the solid electrolyte interphase (SEI) is developed to enhance the interfacial stability and lithium storage reversibility of SnO2 by compositing it with graphite (G) and an inorganic component of the SEI, such as Li2CO3 or LiF, which results in the SnO2-Li2CO3/G and SnO2-LiF/G composite anodes with high CEs, large capacities and long cycle lives. Specifically, the SnO2-Li2CO3/G composite anode exhibits an average initial CE of 79.6%, a stable reversible capacity of 927.5 mA h g−1 at a current rate of 0.2 A g−1, and a charge capacity over 1200 mA h g−1 with a CE >99% after 900 cycles at a higher current rate of 1 A g−1. It is revealed that Li2CO3 induces the formation of a dense and stable SEI on SnO2 grains and inhibits the coarsening of nanosized Sn particles generated from the dealloying reaction in the SnO2-Li2CO3/G electrode. Moreover, the CE and cycling stability of other alloying-type (Si) and conversion reaction (MnO2 and Fe3O4) anodes can also be greatly promoted by simply milling with Li2CO3. Thus, a universal and simple strategy is developed to achieve highly reversible and stable electrodes for large-capacity lithium storage.

Deep learning has been used to reconstruct super-resolution structured illumination microscopy (SR-SIM) images with wide-field or fewer raw images, effectively reducing photobleaching and phototoxicity. However, the dependability of new structures or sample observation is still questioned using these methods. Here, we propose a dynamic SIM imaging strategy: the full raw images are recorded at the beginning to reconstruct the SR image as a keyframe, then only wide-field images are recorded. A deep-learning-based reconstruction algorithm, named KFA-RET, is developed to reconstruct the rest of the SR images for the whole dynamic process. With the structure at the keyframe as a reference and the temporal continuity of biological structures, KFA-RET greatly enhances the quality of reconstructed SR images while reducing photobleaching and phototoxicity. Moreover, KFA-RET has a strong transfer capability for observing new structures that were not included during network training.

This work demonstrated that the solar inactivation of fungal spores was enhanced by addition of low-dose chlorine. Although the effect of low-dose chlorine alone (2.0 mg/L) on culturability of fungal spores was negligible, the solar/chlorine inactivation on fungal spores performed better than solar alone inactivation, with a lower shoulder length and a higher maximum inactivation rate constant. The enhanced inactivation of Aspergillus niger can be ascribed to the membrane oxidation by chlorine, and the enhanced inactivation of Penicillium polonicum can be ascribed to the membrane oxidation by chlorine and ·OH (·OH plays a major role). The oxidization by chlorine and ·OH led to an increase in membrane permeability of fungal spores, which enhanced the solar inactivation, resulting in an increase in intracellular ROS and more serious morphological damage. Due to the presence of background substances such as dissolved organic matter and metal ions (Fe

Induced (natural) mixing proposed by our teams can solve a big problem of low-energy water situation improvement of stratified reservoirs by minimizing operating periods of water-lifting aerators (WLAs) to advance a complete natural mixing. Here, the mechanisms influencing water situation via induced mixing were systematically explored using a combination of multi-water-environment assessment methods including trophic level index (TLI), water quality index (WQI), and minimum WQI (WQI

Water-lifting aerators (WLAs) are often applied in stratified reservoirs to activate artificial mixing to inhibit harmful algal blooms (HABs). Here, the effects, mechanisms, and operational thresholds of spring Dinoflagellate control via artificial mixing were studied using a combination of taxonomic and functional groups and boundary line models. Algal cell density at two sampling sites (i.e., S1 and S2) decreased to below 1.0 × 10

Symmetry is usually defined via transformations described by a (higher) group. But a symmetry really corresponds to an algebra of local symmetric operators, which directly constrains the properties of the system. In this paper, we point out that the algebra of local symmetric operators contains a special class of extended operators -- transparent patch operators, which reveal the selection sectors and hence the corresponding symmetry. The algebra of those transparent patch operators in $n$-dimensional space gives rise to a non-degenerate braided fusion $n$-category, which happens to describe a topological order in one higher dimension (for finite symmetry). Such a holographic theory not only describes (higher) symmetries, it also describes anomalous (higher) symmetries, non-invertible (higher) symmetries (also known as algebraic higher symmetries), and non-invertible gravitational anomalies. Thus, topological order in one higher dimension, replacing group, provides a unified and systematic description of the above generalized symmetries. This is referred to symmetry/topological-order (Symm/TO) correspondence. Our approach also leads to a derivation of topological holographic principle: \emph{boundary uniquely determines the bulk}, or more precisely, the algebra of local boundary operators uniquely determines the bulk topological order. As an application of the Symm/TO correspondence, we show the equivalence between $\mathbb{Z}_2\times \mathbb{Z}_2$ symmetry with mixed anomaly and $\mathbb{Z}_4$ symmetry, as well as between many other symmetries, in 1-dimensional space., 35 pages, 21 figures; PRB version

In this work, we use Ising chain and Kitaev chain to check the validity of an earlier proposal in arXiv:2011.02859 that enriched fusion (higher) categories provide a unified categorical description of all gapped/gapless quantum liquid phases, including symmetry-breaking phases, topological orders, SPT/SET orders and certain gapless quantum phases. In particular, we show explicitly that, in each gapped phase realized by these two models, the spacetime observables form a fusion category enriched in a braided fusion category. We also study the categorical descriptions of the boundaries of these models. In the end, we provide a classification of and the categorical descriptions of all 1-dimensional (the spatial dimension) gapped quantum phases with a finite onsite symmetry., Comment: 27 pages. We add some remarks and references