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The human living environment serves as a habitat for microorganisms and the presence of ubiquitous airborne microbes significantly impacts the natural material cycle. Through ongoing experimentation with beneficial microorganisms, humans have greatly benefited from airborne microbes. However, airborne pathogens endanger human health and have the potential to induce fatal diseases. Tracking airborne microbes is a critical prerequisite for a better understanding of bioaerosols, harnessing their potential advantages, and mitigating associated risks. Although technological breakthroughs have enabled significant advancements in accurately monitoring airborne pathogens, many puzzles about these microbes remain unanswered due to their high variability and environmental diffusibility. Consequently, advanced techniques and strategies for special identification, early warning, and efficient eradication of microbial contamination are continuously being sought. This review presents a comprehensive overview of the research status of airborne microbes, concentrating on the recent advances and challenges in sampling, detection, and inactivation. Particularly, the fundamental design principles for the collection and timely detection of airborne pathogens are described in detail, as well as critical factors for eliminating microbial contamination and enhancing indoor air quality. In addition, future research directions and perspectives for controlling airborne microbes are also suggested to promote the translation of basic research into real products.
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Passive polarimetric imaging has gained substantial attention over the past three decades in various applications in defense. The complexity of polarimetry modeling and measurement in the thermal infrared exceeds that of the visible and near-infrared due to the complementary polarization orientation of reflected and emitted radiance. This paper presents a comprehensive polarimetric radiance model and a degree of linear polarization (DOLP) model, both of which are specifically tailored for the infrared spectrum, accounting for both reflected and emitted radiance. Building on this foundation, we conduct an analysis and simulation of the DOLP's variation as the object temperature changes. This analysis enables the observation of relationships that can be strategically utilized in subsequent experiments focused on measuring polarized model parameters. To mitigate the influence of reflected radiance components, the samples are subjected to high temperatures. The observed Stokes images from the sample surfaces are normalized to eliminate the dependence of each Stokes image on temperature. This parameters acquisition measurement method is particularly well-suited for refractories. Finally, the efficacy of the polarized model parameters acquisition technique is demonstrated through experiments involving three distinct refractory materials in the MWIR.
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The Three Gorges Reservoir (TGR) is totally manmade, strongly influenced by anthropogenic activity, and lies on the upper reaches of Yangtze River. The periodic storage and discharge of water from the Three Gorges Dam could have altered the original air-plant/soil interactions of contaminants in TGR. Herein, paired atmospheric gas-particle, air-plant, and air-soil samples were collected to investigate the air-plant interaction and air-soil exchange of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs). The air-plant interaction based on McLachlan's framework to our datasets suggests that PAHs were absorbed via gaseous deposition that was restricted by the plant-gas dynamic equilibrium. The equilibrium indicates a dynamic balance between the gaseous phase and plant surface in PAH absorption. The main limiting factor influencing the PAH uptake was the plant species rather than the atmospheric PAH concentration. The air-soil exchange of PAHs exhibited a net volatilization flux of 16.71 ng/m2/d from the soil to the air based on annual average. There was more volatilization and less deposition in summer and more deposition and less volatilization in autumn and winter. The soil serves as a secondary source of atmospheric PAHs. As the first attempt on probing the multi-interface geochemical process of PAHs, this study highlights the influence of manual water level manipulation from the TGD and environmental factors (such as temperature, humidity, and soil properties) on the regional fate of PAHs in the TGR.
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Contaminantes Atmosféricos , Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Suelo , Hidrocarburos Policíclicos Aromáticos/análisis , China , Contaminantes Atmosféricos/análisis , Suelo/química , Contaminantes del Suelo/análisis , Plantas/metabolismo , Contaminantes Químicos del Agua/análisis , HumanosRESUMEN
Tenascin C (TNC), a rich glycoprotein of the extracellular matrix, exhibits a pro-atherosclerosis or anti-atherosclerosis effect depending on its location. TNC, especially its C domain/isoform (TNC-C), is strongly overexpressed in atherosclerotic plaque active areas but virtually undetectable in most normal adult tissues, suggesting that TNC is a promising delivery vector target for atherosclerosis-targeted drugs. Many delivery vectors were investigated by recognizing TNC-C, including G11, G11-iRGD, TN11, PL1, and PL3. F16 and FNLM were also investigated by recognizing TNC-A1 and TNC, respectively. Notably, iRGD was undergoing clinical trials. PL1 not only recognizes TNC-C but also the extra domain-B (EDB) of fibronectin (FN), which is also a promising delivery vector for atherosclerosis-targeted drugs, and several conjugate agents are undergoing clinical trials. The F16-conjugate agent F16IL2 is undergoing clinical trials. Therefore, G11-iRGD, PL1, and F16 have great development value. Furthermore, ATN-RNA and IMA950 were investigated in clinical trials as therapeutic drugs and vaccines by targeting TNC, respectively. Therefore, targeting TNC could greatly improve the success rate of atherosclerosis-targeted drugs and/or specific drug development. This review discussed the role of TNC in atherosclerosis, atherosclerosis-targeted drug delivery vectors, and agent development to provide knowledge for drug development targeting TNC.
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Aterosclerosis , Placa Aterosclerótica , Adulto , Humanos , Tenascina/genética , Aterosclerosis/tratamiento farmacológico , Matriz Extracelular , Placa Aterosclerótica/tratamiento farmacológico , Isoformas de ProteínasRESUMEN
Heavy metals (e.g., Cu) in wastewater are attractive resources for diverse applications, and adsorption is a promising route to recovery of heavy metals from wastewater. However, high-performance adsorbents with high adsorption capacity, speed, and stability remain challenging. Herein, chelating fibers were prepared by chemically grafting amine and carboxyl groups onto the polyacrylonitrile fiber surface and used in the wastewater's adsorption of Cu2+. The adsorption behavior of Cu2+ on the fibers was systematically investigated, and the post-adsorption fibers were comprehensively characterized to uncover the adsorption mechanism. The results show that chelated fiber has a 136.3 mg/g maximum capacity for Cu2+ adsorption at pH = 5, and the whole adsorption process could reach equilibrium in about 60 min. The adsorption process corresponds to the quasi-secondary kinetic and Langmuir models. The results of adsorption, FTIR, and XPS tests indicate that the synergistic coordination of -COOH and -NH2 plays a leading role in the rapid capture of Cu2+. In addition, introducing hydrophilic groups facilitates the rapid contact and interaction of the fibers with Cu2+ in the solution. After being used five times, the fiber's adsorption capacity remains at over 90% of its original level.
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Resinas Acrílicas , Metales Pesados , Contaminantes Químicos del Agua , Cobre/química , Aguas Residuales , Poliaminas , Iones , Adsorción , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de HidrógenoRESUMEN
Single-cell RNA sequencing (scRNA-Seq) technology has emerged as a powerful tool to investigate cellular heterogeneity within tissues, organs, and organisms. One fundamental question pertaining to single-cell gene expression data analysis revolves around the identification of cell types, which constitutes a critical step within the data processing workflow. However, existing methods for cell type identification through learning low-dimensional latent embeddings often overlook the intercellular structural relationships. In this paper, we present a novel non-negative low-rank similarity correction model (NLRSIM) that leverages subspace clustering to preserve the global structure among cells. This model introduces a novel manifold learning process to address the issue of imbalanced neighbourhood spatial density in cells, thereby effectively preserving local geometric structures. This procedure utilizes a position-sensitive hashing algorithm to construct the graph structure of the data. The experimental results demonstrate that the NLRSIM surpasses other advanced models in terms of clustering effects and visualization experiments. The validated effectiveness of gene expression information after calibration by the NLRSIM model has been duly ascertained in the realm of relevant biological studies. The NLRSIM model offers unprecedented insights into gene expression, states, and structures at the individual cellular level, thereby contributing novel perspectives to the field.
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Análisis de la Célula Individual , Análisis de Expresión Génica de una Sola Célula , Análisis de la Célula Individual/métodos , Algoritmos , Análisis por Conglomerados , Análisis de Secuencia de ARN/métodos , Perfilación de la Expresión Génica/métodosRESUMEN
Since the authors are not responding to the editor's requests to fulfill the editorial requirement, therefore, the article has been withdrawn.Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused.The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php BENTHAM SCIENCE DISCLAIMER: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.
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Public awareness of the potential environmental risks of shale gas extraction has increased in recent years. However, the status and environmental risks of potentially toxic metals (PTMs) in shale gas field soil remain unclear. A total of 96 topsoil samples were collected from the first shale gas exploitation area in China. The sources of nine PTMs in the soils were identified using positive matrix factorization and correlation analysis, and the ecological and human health risks of toxic metals from different sources under the two land use types were calculated. The results showed that mean pollution load index (PLI) values for farmland (1.18) and woodland (1.40) indicated moderate pollution, As, Cd and Ni were the most serious contaminants among all nine PTMs. The following four sources were identified: shale gas extraction activities (43.90%), nature sources (31.90%), agricultural and traffic activities (17.55%) and industrial activities (6.55%). For ecological risk, the mean ecological risk index (RI) values for farmlands (161.95) and woodlands (185.27) reaching considerable risk. The contribution ratio of shale gas extraction activities for farmlands and woodlands were 5.70% and 8.90%, respectively. Regarding human health risk, noncarcinogenic risks for adults in farmlands and woodlands were negligible. Industrial activities, agricultural and traffic activities were estimated to be the important sources of health risks. Overall, shale gas extraction activities had little impact on the ecological and human health risk. This study provides scientific evidence regarding the soil contamination potential of shale gas development activities.
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Metales Pesados , Contaminantes del Suelo , Humanos , Suelo , Monitoreo del Ambiente/métodos , Gas Natural/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Medición de Riesgo , ChinaRESUMEN
Corneal epithelial defects and excessive wound healing might lead to severe complications. As stem cells can self-renew infinitely, they are a promising solution for regenerating the corneal epithelium and treating severe corneal epithelial injury. The chemical and biophysical properties of biological scaffolds, such as the amniotic membrane, fibrin, and hydrogels, can provide the necessary signals for stem cell proliferation and differentiation. Multiple researchers have conducted investigations on these scaffolds and evaluated them as potential therapeutic interventions for corneal disorders. These studies have identified various inherent benefits and drawbacks associated with these scaffolds. In this study, we provided a comprehensive overview of the history and use of various stem cells in corneal repair. We mainly discussed biological scaffolds that are used in stem cell transplantation and innovative materials that are under investigation.
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Córnea , Lesiones de la Cornea , Trasplante de Células Madre , Ingeniería de Tejidos , Andamios del Tejido , Cicatrización de Heridas , Trasplante de Células Madre/métodos , Córnea/fisiología , Córnea/cirugía , Andamios del Tejido/efectos adversos , Andamios del Tejido/química , Lesiones de la Cornea/cirugía , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología , Humanos , AnimalesRESUMEN
Bi-based materials are promising electrocatalysts for CO2 reduction but one of the key technological hurdles is the design of stable, active and affordable Bi-based catalysts over a wide potential range. Herein, Bi2S3/CNTs nanocomposites are constructed by anchoring bismuth sulfide (Bi2S3) nanorods onto the multiwalled carbon nanotubes (CNTs) and utilizing them in electrocatalytic CO2 reduction. CNTs, as a support, not only guarantee the conductivity and dispersibility of Bi2S3 nanorods but also improve the electrolyte infiltration and optimize the electronic structure of the Bi2S3. As expected, the Bi2S3/CNTs nanocomposite exhibits a faradaic efficiency for HCOO- (FEHCOO-) of 99.3% with a current density of -20.3 mA cm-2 at -0.91 V vs. RHE. The FEHCOO- is stably maintained at over > 91% in a wide potential window from -0.71 V to -1.31 V. Theoretical calculation analyses reveal that the strong interaction between Bi2S3 and CNTs is conductive to decreasing the energy barrier of *OCHO, stabilizing the intermediate *OCHO, and inhibiting the hydrogen evolution reaction. The current study provides an insightful understanding of the mechanism of the CO2 electroreduction reaction, and paves a new way for developing superior and affordable electrocatalysts.
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The processes of hydraulic fracturing to extract shale gas generate a large amount of wastewater, and the potential impacts of wastewater discharge after treatment are concerning. In this field study, we investigated the effects of the irrigation of paddy fields for 2 consecutive years by river water that has been influenced by shale gas wastewater discharge on soil physicochemical properties, microbial community structure and function, and rice grain quality. The results showed that conductivity, chloride and sulfate ions in paddy soils downstream of the outfall showed an accumulative trend after two years of irrigation, but these changes occurred on a small scale (<500 m). Two-year irrigation did not cause the accumulation of trace metals (barium, cadmium, chromium, copper, lead, strontium, zinc, nickel, and uranium) in soil and rice grains. Among all soil parameters, the accumulation of chloride ions was the most pronounced, with concentrations in the paddy soil at the discharge site 13.3 times higher than at the upstream control site. The use of influenced river water for paddy irrigation positively increased the soil microbial diversity, but these changes occurred after two years of irrigation and did not occur after one year of irrigation. Overall, the use of river water affected by shale gas wastewater discharge for agricultural irrigation has limited effects on agroecosystems over a short period. Nevertheless, the possible negative effects of contaminant accumulation in soil and rice caused by longer-term irrigation should be seriously considered.
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Microbiota , Oryza , Contaminantes del Suelo , Suelo/química , Aguas Residuales , Gas Natural , Cloruros , Riego Agrícola , Agua , Oryza/química , Contaminantes del Suelo/análisisRESUMEN
Polycyclic aromatic hydrocarbons (PAHs) pose a great threat to human health and ecological system safety. The interception of nitrogen is common found in the riparian zone. However, there is no evidence on how nitrogen addition affects the anaerobic degradation of PAHs in soil of the water-level-fluctuation zone (WLFZ) of the Three Gorges Reservoir (TGR) in Yangtze River, China. Here, we investigated the PAHs degradation rate, the variation of key functional genes and microbial communities after nitrogen addition in soil that experienced a flooding period of water-level-fluctuation. The results revealed that the ∑16PAHs were decreased 16.19 %-36.65 % and more 3-5-rings PAHs were biodegraded with nitrogen addition in WLFZ. The most genes involved in PAHs-anaerobic degradation and denitrification were up-regulated by nitrate addition, and phyla Firmicutes, Actinobacteria and Proteobacteria were more advantages in nitrogen addition groups. The Tax4Fun based genome function analysis revealed that the microbial activity of PAHs-degradation increased with nitrate addition. The co-occurrence network analysis indicated that nitrogen addition accelerated the metabolism of nitrogen and PAHs. It is the first time to provide the direct experimental evidences that nitrogen transformation in the WLFZ soil promotes anaerobic PAHs degradation. This work is of importance to understand the effect of nitrogen intercepted in the WLFZ soil of TGR in Yangtze River, China.
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Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Humanos , Ríos , Hidrocarburos Policíclicos Aromáticos/análisis , Agua/análisis , Nitrógeno/análisis , Nitratos/análisis , Anaerobiosis , Suelo , China , Contaminantes Químicos del Agua/análisisRESUMEN
Microbial electrosynthesis (MES) enables the bioproduction of multicarbon compounds from CO2 using electricity as the driver. Although high salinity can improve the energetic performance of bioelectrochemical systems, acetogenic processes under elevated salinity are poorly known. Here MES under 35-60 g L-1 salinity was evaluated. Acetate production in two-chamber MES systems at 35 g L-1 salinity (seawater composition) gradually decreased within 60 days, both under -1.2 V cathode potential (vs. Ag/AgCl) and -1.56 A m-2 reductive current. Carbonate precipitation on cathodes (mostly CaCO3) likely declined the production through inhibiting CO2 supply, the direct electrode contact for acetogens and H2 production. Upon decreasing Ca2+ and Mg2+ levels in three-chamber reactors, acetate was stably produced over 137 days along with a low cathode apparent resistance at 1.9 ± 0.6 mΩ m2 and an average production rate at 3.80 ± 0.21 g m-2 d-1. Increasing the salinity step-wise from 35 to 60 g L-1 gave the most efficient acetate production at 40 g L-1 salinity with average rates of acetate production and CO2 consumption at 4.56 ± 3.09 and 7.02 ± 4.75 g m-2 d-1, respectively. The instantaneous coulombic efficiency for VFA averaged 55.1 ± 31.4%. Acetate production dropped at higher salinity likely due to the inhibited CO2 dissolution and acetogenic metabolism. Acetobacterium up to 78% was enriched on cathodes as the main acetogen at 35 g L-1. Under high-salinity selection, 96.5% Acetobacterium dominated on the cathode along with 34.0% Sphaerochaeta in catholyte. This research provides a first proof of concept that MES starting from CO2 reduction can be achieved at elevated salinity.
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The sulfate-reducing mediate microbial fuel cell (MFC) shows advantages in treating recalcitrant flowback water (FW) from shale gas extraction, but the stability under fluctuant concentrations of sulfate in FW remains unknown. Herein, we investigated the impact of fluctuant sulfate concentrations on the performance of FW treatment in MFCs. Sulfate concentration showed a significant role in the MFC treating FW, with a COD removal of 69.8 ± 9.7% and a peak power density of 2164 ± 396 mW/m3 under 247.5 mg/L sulfate, but only 39.1% and 1216 mW/m3 under 50 mg/L sulfate. The fluctuation of sulfate in a short time allowed to a stable performance, but a longtime intermittent decrease of feeding sulfate concentration significantly inhibited power generation to no more than 512 mW/m3. The sulfur cycling between sulfate and sulfide existed in the system, but the cycling rate became much lower after the longtime intermittent decrease, with resulting to the decreased power generation. Abundant sulfur-oxidizing bacteria (SOB) of Desulfuromonadaceae and Helicobacteraceae in the MFC stably feeding with 247.5 mg/L sulfate supported a high sulfur cycling rate. With the cooperation of abundant sulfate-reducing bacteria (SRB) of Desulfovibrionaceae (capable of producing electricity) on the anode and Desulfobacteraceae in anolyte, this sulfur cycling endowed the MFC with high sulfate tolerance and critically contributed to recalcitrant organics removal and power generation. However, much less SOB of Helicobacteraceae and Campylobacteraceae on the anode with high S0 accumulation on the surface after the longtime intermittent decrease of sulfate likely led to the low sulfur cycling rate. With also less SRB of Marinilabiaceae (capable of producing electricity) and Synergistaceae in the system, this low sulfur cycling rate thus hampered power generation. This research provides an important reference for the bioelectrochemical treatment of wastewater containing recalcitrant organics and sulfate.
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Fuentes de Energía Bioeléctrica , Desulfovibrio , Purificación del Agua , Fuentes de Energía Bioeléctrica/microbiología , Aguas Residuales , Gas Natural , Azufre/metabolismo , Sulfatos/metabolismo , Desulfovibrio/metabolismo , Bacterias/metabolismo , Sulfuros/metabolismoRESUMEN
With the development of research on the complex aetiology of many diseases, computational drug repositioning methodology has proven to be a shortcut to costly and inefficient traditional methods. Therefore, developing more promising computational methods is indispensable for finding new candidate diseases to treat with existing drugs. In this paper, a model integrating a new variant of message passing neural network and a novel-gated fusion mechanism called GLGMPNN is proposed for drug-disease association prediction. First, a light-gated message passing neural network (LGMPNN), including message passing, aggregation and updating, is proposed to separately extract multiple pieces of information from the similarity networks and the association network. Then, a gated fusion mechanism consisting of a forget gate and an output gate is applied to integrate the multiple pieces of information to extent. The forget gate calculated by the multiple embeddings is built to integrate the association information into the similarity information. Furthermore, the final node representations are controlled by the output gate, which fuses the topology information of the networks and the initial similarity information. Finally, a bilinear decoder is adopted to reconstruct an adjacency matrix for drug-disease associations. Evaluated by 10-fold cross-validations, GLGMPNN achieves excellent performance compared with the current models. The following studies show that our model can effectively discover novel drug-disease associations.
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Biología Computacional , Redes Neurales de la Computación , Biología Computacional/métodos , Reposicionamiento de Medicamentos/métodos , AlgoritmosRESUMEN
A novel method was used to fabricate the bio-carrier with both a high specific surface area and good compatibility. The results of monitoring the growth of biofilms at a low C/N ratio (0.83) showed that resulting carrier-PLA-cavity offered certain advantages for biofilm growth by providing an appropriate microenvironment for bacterial growth in wastewater treatment. The biofilm on carrier-PLA-cavity grew and updated faster than the naked-carrier. The biomass and thickness of biofilms growing on carrier-PLA-cavity were 10 kg/m3 and 500 µm, respectively. From the wastewater tests, 90% of the total nitrogen was removed via simultaneous nitrification and denitrification (SND) by the biofilm biomass attached to carrier-PLA-cavity, compared to 68% for the naked-carrier. The COD removal efficiency values of the carrier-PLA-cavity and naked-carrier were 94% and 86%, respectively. The microbial community analysis of carrier biofilms showed that Halomonas was the most abundant genus, and heterotrophic nitrification and denitrification were responsible for nitrogen removal in both reactors. Notably, this method does not require any complicated equipment or structural design. This novel method might be a promising strategy for fabricating biocarriers for treating wastewater with a low C/N ratio.
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The potential threats of shale gas wastewater discharges to receiving waters is of great concern. In this study, chemical analyses and biomonitoring were performed three times in a small river that received treated wastewater over a two-year period. The results of chemical analyses showed that the concentrations of chloride, conductivity, barium, and strontium increased at the discharge site, but their concentrations decreased considerably farther downstream (≥500 m). The concentrations of toxic organic compounds (16 US EPA priority polycyclic aromatic hydrocarbons and 6 priority phthalates), trace metals (strontium, arsenic, zinc, copper, chromium, lead, cadmium, nickel, and neodymium), and natural radionuclides (40K, 238U, 226Ra, and 232Th) were comparable to the corresponding background values or did not exhibit obvious accumulation in sediments with continued discharge. Morphological and environmental DNA approaches were used to reveal the potential effects of wastewater discharges on aquatic ecosystems. The results showed that the community structure of benthic invertebrates was not altered by the long-term discharges of shale gas wastewaters. However, the biodiversity indices (richness and Shannon) from the two approaches showed inconsistencies, which were caused by multiple reasons, and that substrates had a strong influence on the morphological biodiversity indices. A multimetric index was proposed to further analyze morphological and environmental DNA data, and the results showed no significant difference between the upstream and downstream sites. Generally, the chemical and biological results both demonstrated that the discharges of shale gas wastewaters had limited impacts on river ecosystems within two years.
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ADN Ambiental , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente , Gas Natural , Compuestos Orgánicos , Estroncio/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/químicaRESUMEN
Single-cell RNA sequencing (scRNA-seq) technology is famous for providing a microscopic view to help capture cellular heterogeneity. This characteristic has advanced the field of genomics by enabling the delicate differentiation of cell types. However, the properties of single-cell datasets, such as high dropout events, noise, and high dimensionality, are still a research challenge in the single-cell field. To utilize single-cell data more efficiently and to better explore the heterogeneity among cells, a new graph autoencoder (GAE)-based consensus-guided model (scGAC) is proposed in this article. The data are preprocessed into multiple top-level feature datasets. Then, feature learning is performed by using GAEs to generate new feature matrices, followed by similarity learning based on distance fusion methods. The learned similarity matrices are fed back to the GAEs to guide their feature learning process. Finally, the abovementioned steps are iterated continuously to integrate the final consistent similarity matrix and perform other related downstream analyses. The scGAC model can accurately identify critical features and effectively preserve the internal structure of the data. This can further improve the accuracy of cell type identification.
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Fracturing flowback water (FFW) from the shale gas exploitation resulted in environmental burden. FFW could be treated by a microbial fuel cell (MFC), but the challenge for the precipitation of ultrafine particles due to the supersaturation of sulfide remains to be addressed. Herein, we reported a Dual-anode MFC (DA-MFC), in which the FFW remediation and elemental sulfur recovery could be performed by regulating potential of the electrochemical anode. The removal of COD and sulfate was 70.0 ± 1.2% and 75.5 ± 0.4% in DA-MFCs by controlling potential at -0.1 V (vs. SHE) for 36 h. Meanwhile, the efficiency of copper removal and elemental sulfur recovery was up to 99.9 ± 0.5% and 75.6 ± 1.8%, respectively, which was attributed by the electrochemical oxidation of sulfide to elemental sulfur. Trichococcus, unclassified Prolixibacteraceae and unclassified Cloacimonadales enriched on the bioanodes of DA-MFCs were sensitive to potential regulation and favorable for degrading complex organics. UnclassifiedSynergistaceae, Desulfobacterium, Desulfovibrio, unclassified bacteria and Syner-01 was conducive to sulfate removal. Moreover, the elimination of Azoarcus due to potential regulation suppressed the biological oxidation of sulfide. Thus, organics were efficiently removed through the biological oxidation and sulfate reduction on bioanode, the copper ions were combined with the sulfide from sulfate reduction to precipitate effectively, and then the excessive sulfide in the system was converted into elemental sulfur attached on the electrochemical anode. The results provide new sights on bio-electrochemical technology for treatment of wastewater containing complex organics, heavy metals and sulfates.
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Fuentes de Energía Bioeléctrica , Fuentes de Energía Bioeléctrica/microbiología , Cobre , Electrodos , Oxidación-Reducción , Sulfatos , Sulfuros , Azufre , Aguas Residuales , AguaRESUMEN
Sixteen paired surface sediment samples (0-5 cm, n = 32) covering upstream to downstream of water-level-fluctuation zone of Three Gorges Reservoir, China were collected in March 2018 (following six months of submergence) and September 2018 (after six months of exposure). Seventeen per- and poly-fluoroalkyl substances (PFASs) were quantified to evaluate contamination characteristics, apportion source categories and estimate mass inventory and loadings. The concentration of ΣPFASs ranged from 0.26 to 0.82 ng·g-1 at high water-level (HWL) and 0.46-1.53 ng·g-1 at low water-level (LWL). Perfluorooctanoic acid (PFOA, mean: 0.32 ng·g-1) and perfluorooctane sulfonate (PFOS, mean: 0.12 ng·g-1) dominated, accounting 44.9% and 16.3% of the total PFASs, respectively. The distribution of PFASs was more influenced by anthropogenic activities than physicochemical parameters of the sediments. Positive matrix factorization (PMF) identified PFOA-based products was the major sources (40.1% and 38.6%, respectively). Besides, the direct sources of PFOA-, PFOS-, PFNA-and PFBA-based products played the predominant role, while the indirect degradation of precursors contributed relatively little. The sediment (0-5 cm) mass inventory of PFASs at LWL (57.5 kg) was higher than HWL (39.3 kg). The annual mass loadings of the total PFASs, PFOA, PFOS, perfluoroundecanoic acid (PFUdA) and perfluorononanoic acid (PFNA) from the upstream to the middle-lower reaches of Yangtze River were 27.4 kg, 11.1 kg, 4.63 kg, 2.89 kg and 2.57 kg, respectively. This study could provide the basic datasets of PFASs in surface sediments of the TGR, and also indicate an important transport of PFASs from upstream to the lower reaches, which should be further studied as well.