The electrochemical activity of bioelectrochemical systems (BESs) was proven to be dependent on the stability of electroactive biofilms (EABs), but the response of EABs based on real wastewater to ...external disturbances is not fully known. Herein, we used real wastewater (beer brewery wastewater) as a substrate for culturing EABs and found that current generation, biomass, redox activity and extracellular polymeric substances (EPS) content in those EABs were lower as compared to EABs cultured with synthetic wastewaters (acetate and glucose). However, the EABs from the beer brewery wastewater showed moderate anti-shock resistance capability. The proteins and humic acid in loosely bound EPS (LB-EPS) exhibited a positive linear relationship with current recovery after Ag+ shock, indicating the importance of LB-EPS for protecting the EABs. Fluorescence and Fourier transform infrared spectroscopy integrated with two-dimensional correlation spectroscopy verified that the spectra of the protein-like region of LB-EPS changed considerably under the interference of Ag+ concentration and the CO group of humic acid or proteins was mainly responsible for binding with Ag+ to attenuate its toxicity to the EABs. This is the first study revealing the underlying molecular mechanism of EABs cultured with real wastewater against external heavy metal shock and provides useful insights into enhancing the application of BESs in future water treatment.
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•EABs from BBW had poorer electrical activity than those from synthetic wastewaters.•EABs from BBW exhibited higher resistance to Ag+ shock than that from glucose.•Oxygen and nitrogen moieties of proteins and humic acid in EPS played important roles in anti-Ag+ shock.
Microplastic is a new type of pollutant, which can act as a carrier for organic contaminants. It affects the migration and bioavailability of chemicals and potentially threatens the ecology. This ...work investigated the adsorption kinetics, isotherm and influencing factors of 17β-estradiol (E2) on three dominate microplastics. Then, used molecular dynamics (MD) simulation to analyze the adsorption mechanism. The results showed that E2 adsorption onto microplastics conformed well to the Pseudo-second-order kinetics and Redlich-Petersen isotherm model. The adsorption capacity of E2 on microplastics was polyethylene (PE) > polypropylene (PP) > polystyrene (PS). The small particle size of microplastics was conducive to the adsorption due to its large specific surface area. The thermodynamic parameters demonstrated the adsorption of E2 was a spontaneous and exothermic process, so low temperature was benefit for the adsorption. The MD simulation results indicated the adsorption of E2 on MPs belonged to surface adsorption. The order of E2 adsorption energy by three microplastics obtained by molecular dynamics simulation is consistent with the experimental results. This work may help to understand the molecular adsorption process and provide a theoretical basis for the combined ecotoxicity of microplastics.
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•17β-estradiol (E2) adsorption onto microplastics conformed to the Pseudo-second-order kinetics and R-P isotherm model.•The capacity of E2 adsorption on microplastics was polyethylene > polypropylene > polystyrene.•The smaller particle size of microplastic and lower temperature were conducive to the adsorption.•The results of molecular dynamics simulation showed the adsorption of E2 on MPs belonged to surface adsorption.
Solar‐driven carbon dioxide (CO2) methanation holds significant research value in the context of carbon emission reduction and energy crisis. However, this eight‐electron catalytic reaction presents ...substantial challenges in catalytic activity and selectivity. In this regard, researchers have conducted extensive exploration and achieved significant developments. This review provides an overview of the recent advances and challenges in efficient selective photocatalytic CO2 methanation. It begins by discussing the fundamental principles and challenges in detail, analyzing strategies for improving the efficiency of photocatalytic CO2 conversion to CH4 comprehensively. Subsequently, it outlines the recent applications and advanced characterization methods for photocatalytic CO2 methanation. Finally, this review highlights the prospects and opportunities in this area, aiming to inspire CO2 conversion into high‐value CH4 and shed light on the research of catalytic mechanisms.
This study presents a comprehensive review of the recent advances and challenges in efficient selective photocatalytic CO2 methanation, including the fundamental principles, challenges, improving strategies, recent applications, and advanced characterization methods. The prospects and opportunities are highlighted to inspire CO2 conversion into high‐value CH4 and shed light on the research of catalytic mechanisms.
Exploring the metabolic characteristics of indigenous PAH degraders is critical to understanding the PAH bioremediation mechanism in the natural environment. While stable‐isotopic probing (SIP) is a ...viable method to identify functional microorganisms in complex environments, the metabolic characteristics of uncultured degraders are still elusive. Here, we investigated the naphthalene (NAP) biodegradation of petroleum polluted soils by combining SIP, amplicon sequencing and metagenome binning. Based on the SIP and amplicon sequencing results, an uncultured Gammaproteobacterium sp. was identified as the key NAP degrader. Additionally, the assembled genome of this uncultured degrader was successfully obtained from the 13C‐DNA metagenomes by matching its 16S rRNA gene with the SIP identified OTU sequence. Meanwhile, a number of NAP degrading genes encoding naphthalene/PAH dioxygenases were identified in this genome, further confirming the direct involvement of this indigenous degrader in the NAP degradation. The degrader contained genes related to the metabolisms of several carbon sources, energy substances and vitamins, illuminating potential reasons for why microorganisms cannot be cultivated and finally realize their cultivation. Our findings provide novel information on the mechanisms of in situ PAH biodegradation and add to our current knowledge on the cultivation of non‐culturable microorganisms by combining both SIP and metagenome binning.
•A dual-working electrode BES was applied for the complete degradation of PCP.•Active degraders on the electrodes in the BES were explored by DNA-SIP.•Microbes for dechlorination and mineralization ...were enriched separately in different biofilms.•Potential autotrophs were found to be involved in the dechlorination of PCP.
Bioelectrochemical system (BES) can effectively promote the reductive dechlorination of chlorophenols (CPs). However, the complete degradation of CPs with sequential dechlorination and mineralization processes has rarely achieved from the BES. Here, a dual-working electrode BES was constructed and applied for the complete degradation of pentachlorophenol (PCP). Combined with DNA-stable isotope probing (DNA-SIP), the biofilms attached on the anodic and cathodic electrode in the BES were analyzed to explore the dechlorinating and mineralizing microorganisms. Results showed that PCP removal efficiency in the dual-working BES (84% for 21 days) was 4.1 and 4.7 times higher than those of conventional BESs with a single anodic or cathodic working electrode, respectively. Based on DNA-SIP and high-throughput sequencing analysis, the cathodic working electrode harbored the potential dechlorinators (Comamonas, Pseudomonas, Methylobacillus, and Dechlorosoma), and the anodic working enriched the potential intermediate mineralizing bacteria (Comamonas, Stenotrophomonas, and Geobacter), indicating that PCP could be completely degraded under the synergetic effect of these functional microorganisms. Besides, the potential autotrophic functional bacteria that might be involved in the PCP dechlorination were also identified by SIP labeled with 13C-NaHCO3. Our results proved that the dual-working BES could accelerate the complete degradation of PCP and enrich separately the functional microbial consortium for the PCP dechlorination and mineralization, which has broad potential for bioelectrochemical techniques in the treatment of wastewater contaminated with CPs or other halogenated organic compounds.
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Hyperglycemia is an independent risk factor for diabetic heart failure. However, the mechanisms that mediate hyperglycemia-induced cardiac damage remain poorly understood. Previous studies have shown ...an association between lysosomal dysfunction and diabetic heart injury. The present study examined if mimicking hyperglycemia in cultured cardiomyocytes could induce lysosomal membrane permeabilization (LMP), leading to the release of lysosome enzymes and subsequent cell death. High glucose (HG) reduced the number of lysosomes with acidic pH as shown by a fluorescent pH indicator. Also, HG induced lysosomal membrane injury as shown by an accumulation of Galectin3-RFP puncta, which was accompanied by the leakage of cathepsin D (CTSD), an aspartic protease that normally resides within the lysosomal lumen. Furthermore, CTSD expression was increased in HG-cultured cardiomyocytes and in the hearts of 2 mouse models of type 1 diabetes. Either CTSD knockdown with siRNA or inhibition of CTSD activity by pepstatin A markedly diminished HG-induced cardiomyocyte death, while CTSD overexpression exaggerated HG-induced cell death. Together, these results suggested that HG increased CTSD expression, induced LMP and triggered CTSD release from the lysosomes, which collectively contributed to HG-induced cardiomyocyte injury.
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•Hyperglycemia induced Cathepsin D in mouse heart and in cultured cardiomyocytes.•High glucose increased lysosomal membrane permeability in cultured cardiomyocytes.•High glucose triggered Cathepsin D leakage from the lysosome in cardiomyocytes.•Cathepsin D knockdown or inhibition reduced high glucose cardiotoxicity.•Cathepsin D overexpression exaggerated high glucose-induced cardiomyocyte death.
Solar-driven carbon dioxide (CO
) methanation holds significant research value in the context of carbon emission reduction and energy crisis. However, this eight-electron catalytic reaction presents ...substantial challenges in catalytic activity and selectivity. In this regard, researchers have conducted extensive exploration and achieved significant developments. This review provides an overview of the recent advances and challenges in efficient selective photocatalytic CO
methanation. It begins by discussing the fundamental principles and challenges in detail, analyzing strategies for improving the efficiency of photocatalytic CO
conversion to CH
comprehensively. Subsequently, it outlines the recent applications and advanced characterization methods for photocatalytic CO
methanation. Finally, this review highlights the prospects and opportunities in this area, aiming to inspire CO
conversion into high-value CH
and shed light on the research of catalytic mechanisms.
A gradient metamaterial with varying-stiffness local resonators is proposed to open the multiple bandgaps and further form a broad fusion bandgap. First, three local resonators with linearly ...increasing stiffness are periodically attached to the spring-mass chain to construct the gradient metamaterial. The dispersion relation is then derived based on Bloch’s theorem to reveal the fusion bandgap theoretically. The dynamic characteristic of the finite spring-mass chain is investigated to validate the fusion of multiple bandgaps. Finally, the effects of the design parameters on multiple bandgaps are discussed. The results show that the metamaterial with a non-uniform stiffness gradient pattern is capable of opening a broad fusion bandgap and effectively attenuating the longitudinal waves within a broad frequency region.
The aim of present work was to investigate the effect of solid-state fermentation with filamentous fungi (Aspergillus oryzae var. effuses, Aspergillus oryzae, and Aspergillus niger) on total ...phenolics content (TPC), flavonoids, and antioxidant activities of four subfractions of oat, namely, n-hexane, ethyl acetate (EA), n-butanol, and water, and compare them to their corresponding subfractions of unfermented oat. The TPC and total flavonoids increased dramatically, especially in EA subfractions (p < 0.05). The levels of antioxidant activity of subfractions were also significantly enhanced (p < 0.05). The highest antioxidant activities were also found in the EA subfractions. The polyphenols in EA were analyzed by high-performance liquid chromatography at 280 nm. Most polyphenols were increased remarkably, especially ferulic and caffeic acids. There was a clear correlation between the TPC and antioxidant activity. In conclusion, fungi fermentation is a potential bioprocess for increasing the TPC, flavonoids, and antioxidant activities of oat-based food.
With the development of 6G technology, Reconfigurable Intelligent Surface (RIS), as one of the core technologies, has received wide attention in recent years. It not only improves the performance of ...the wireless communication system but also constructs a new localization scenario that utilizes the RIS as assistance. The RIS-aided positioning system can improve the localization performance of the Non-Line-of-Sight (NLoS) environment by building Virtual-Line-of-Sight (VLoS) links. However, it also faces challenges. First, the Cramér-Rao Lower Bound (CRLB), which is usually utilized to evaluate the system performance, has been analyzed only based on one or two parameters in existing research. It is not precise enough under the practical situation. Second, since there are many passive reflective elements on the RIS, applying all of them to localization will not only increase the storage space but even decrease the localization accuracy due that some elements may provide ambiguous information. Therefore, in order to solve the above problems, we first analyzed the CRLB of multi-parameter estimation to be consistent with the real environment. Second, a cutting-edge metaheuristic optimization algorithm, i.e., Artificial Rabbits Optimization (ARO) algorithm, is proposed to optimize the passive reflective elements, which aims to minimize the CRLB to increase the location accuracy while reducing the storage simultaneously. The experimental results show that the multi-parameter CRLB analysis is more in line with the actual situation. In addition, after the RIS passive reflective elements optimization, it improves the location accuracy by about 15.26<inline-formula><tex-math notation="LaTeX">\%</tex-math></inline-formula> compared with using all elements.
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