Publications by authors named "Nanqi Ren"

The dissemination of antibiotic resistance genes (ARGs) poses global environmental issues, and plasmid-mediated conjugation contributes substantially to the spread of ARGs. Quorum sensing (QS), an important cell-cell communication system that coordinates group behaviors, has potential as a feasible regulation pathway to inhibit the conjugation process. We examined the promoting effects of QS signal on conjugation, and this study is the first to report that QS inhibitors 2(3H)-benzofuranone and acylase I effectively repressed conjugation frequency of RP4 plasmid to 0.

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China faces severe water scarcity and significant greenhouse gas (GHG) emission pressures. As significant sources of GHG emission within urban system, wastewater treatment plants (WWTPs) exhibit a clear coupling relationship between wastewater treatment and urban water usage. However, the lack of trace of the water‑carbon nexus has created an obstacle to coordinating water utilization strategies and low-carbon wastewater treatment.

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The carbon-neutral target presents a significant challenge for the sewage sludge treatment and disposal (SSTD) industry, necessitating strategic planning for a low-carbon transition. However, flexible and comprehensive carbon emission analysis tools to support this goal remain lacking. This study presents a carbon emission analysis tool to evaluate the carbon emission characteristics and future mitigation potentials of SSTD.

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Despite extensive global attention on microplastic pollution, our understanding of the pathways underlying microplastic translocation, accumulation, and their potential impacts on ecosystems and human health through the food chain remains incomplete. To investigate the translocation and accumulation of microplastics from insects to mammals, we developed a novel oral exposure model that Tenebrio molitor larvae (yellow mealworms, invertebrate terrestrial insects) were firstly orally exposed to both micro and nanometer-sized plastics (M/NPs), and subsequently fed as a food source to mice (mammals). Our results provide clear evidence that micro/nanoplastics (M/NPs) do indeed translocate through the food chain, from lower to higher trophic levels.

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To develop clean energy utilization of sewage sludge, this study investigated the conversion behavior of organics and energy in supercritical sludge-ethanol system. The influence of liquefied parameters on products distribution, hydrogen supply process of ethanol for sludge liquefaction, migration of organics, and energy transformation were investigated. Results indicated that ethanol acted as both a solvent and a hydrogen donor.

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Within the context of circular economy and industrial ecology, adsorption offers an effective manner for recycling resources from wastewater, but controllable desorption remains a challenge. Inspired by metal-thiol binding and reversible thiol-disulfide redox transformation in biological systems, this study reports the development of a reversible adsorption/desorption (RAD) system for controllable recovery of copper based on electrochemically switchable sulfurized polyacrylonitrile (SPAN). Density functional theory calculations offered theoretical prediction for the formation of S-Cu bonds and reversible weak interaction between S-S bonds and Cu.

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Article Synopsis
  • Sulfur-mediated biological nitrogen removal (BNR) processes are more effective at reducing greenhouse gas (GHG) emissions than traditional heterotrophic methods, especially in micro-oxygen environments.
  • The review discusses the microorganisms involved in sulfur-mediated BNR, focusing on their metabolic interactions and mechanisms under these specific conditions.
  • It emphasizes the GHG reduction potential of these processes and suggests future strategies for managing GHG emissions in wastewater treatment systems.
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  • The study investigated how nano-magnetite improves dissimilatory iron reduction (DIR) in sewage, specifically focusing on the formation of vivianite, a common product of DIR.
  • Incorporation of nano-magnetite increased the abundance of beneficial bacteria like Comamonas and Geobacter and significantly boosted microbial protein content during the DIR process.
  • The findings highlighted nano-magnetite's role in enhancing electron transfer by creating conductive pathways, promoting vivianite recovery, and advancing the understanding of mineral-microbe interactions in nutrient recovery.
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Anaerobic ammonium oxidation bacteria (AAOB), distinguished by their unique autotrophic nitrogen metabolism, hold pivotal positions in the global nitrogen cycle and environmental biotechnologies. However, the ecophysiology and evolution of AAOB remain poorly understood, attributed to the absence of monocultures. Hence, a comprehensive elucidation of the AAOB-dominated core microbiome, anammox core, is imperative to further completing the theory of engineered nitrogen removal and ecological roles of anammox.

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Medium-chain carboxylic acids (MCCAs) show great promise as commercial chemicals due to their high energy density, significant product value, and wide range of applications. The production of MCCAs from waste biomass through coupling chain extension with anaerobic fermentation represents a new and innovative approach to biomass utilization. This review provides an overview of the principles of MCCAs production through coupled chain extension and anaerobic fermentation, as well as the extracellular electron transfer pathways and microbiological effects involved.

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Global monitoring of persistent organic pollutants (POPs) has intensified following regulatory efforts aimed at reducing their release. In this context, we compiled over 10,000 POP measurements, reported from 1980 to 2023, to assess the effectiveness of these legislative measures in the global marine environments. While a general decreasing trend in legacy POP concentrations is evident across various maritime regions, highlighting the success of source control measures, the Arctic Ocean and its marginal seas have experienced a rise in POP levels.

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Heavy metal pollution in the cold region is serious, affecting human health and aquatic ecology. This study investigated the ability of microalgae to remove heavy metals (HMs) and produce lipid at low temperature. The removal efficiency of different HMs (Cd, Cu, Cr and Pb), cell growth and lipid synthesis of microalgae were analyzed at 15 °C.

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Article Synopsis
  • The Integrated Fixed-Film Activated Sludge (IFAS) system enhances the traditional activated sludge process by combining the benefits of attached and suspended sludge for improved nutrient removal.
  • A study utilized metagenomic analysis to evaluate the roles of attached sludge (AS) and suspended sludge (SS), revealing that AS is crucial for nitrogen (N) reduction, while SS plays a significant role in phosphorus (P) release and uptake.
  • Key findings highlighted that AS has higher levels of nitrate and nitrite reductase activity, whereas SS exhibits more activity in phosphatase enzymes, with different microbial communities and gene expressions affecting N and P removal efficiencies in the IFAS system.
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Article Synopsis
  • Plastics aging decreases resistance to microbial degradation, and the mealworm Tenebrio molitor can biodegrade polystyrene (PS) effectively, but how aging affects this process is not well-studied.
  • In a 24-day study, various pre-treatments (freezing with UV, UV only, and freezing) were used on PS microplastics, resulting in slightly better PS consumption and mass reduction compared to pristine PS.
  • The study found that while aging treatments slightly improved PS biodegradation, they significantly affected the gut microbial diversity of the mealworms and their metabolic pathways, showing their capacity to adapt to altered PS plastics.
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The report demonstrated that a member of cockroach family, Blaptica dubia (Blattodea: Blaberidae) biodegraded commercial polystyrene (PS) plastics with M of 20.3 kDa and M of 284.9 kDa.

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The aim of this study was to investigate the effects of various concentrations of antioxidants, including butyl hydroxy anisd (BHA), butylated hydroxytoluene (BHT), fulvic acid (FA), melatonin (MT), glycine betaine (GB) and putrescine (Put), on growth and lipid synthesis of microalgae under low-temperature (15 ℃). Changes in biochemical indicators, reactive oxygen species (ROS) level, glutathione (GSH) content and antioxidant enzyme activities were also studied. The results indicated that the maximum biomass concentration (1.

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In this study, a peracetic acid (PAA) alone process was systematically demonstrated to give a high efficiency in the selective degradation of sulfonamide antibiotics (SAs). The employment of scavengers and probe compounds in this process demonstrates the predominant role of PAA in direct oxidation, and the limited role of carbon-centered radicals (R-O) in the degradation of representative SA, sulfamethazine (SMT). The process also exhibits high tolerance towards solution pH and competing anions in wastewater, indicating its applicability in enhancing the biodegradation of SAs in wastewater.

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Freeze-thaw cycle (FTC) is a naturally occurring phenomenon in high-latitude terrestrial ecosystems, which may exert influence on distribution and evolution of microbial community in the soil. The relationship between transmission of antibiotic resistance genes (ARGs) and microbial community was investigated upon the case study on the soil of cold-region dairy farm under seasonal FTC. The results demonstrated that 37 ARGs underwent decrease in the abundance of blaTEM from 80.

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Riparian zones play a vital role in the river ecosystem. Solutes in vertical riparian zones are transported being by alternating hydraulic gradients between river water and groundwater, due to natural or human activities. This study investigates the impacts of porous sediments and alternating rate of surface water-groundwater on nitrogen removal in the riparian zone through experiments based on the field sampled.

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The main pressing problems should be solved for heterogeneous catalysts in activation of peroxymonosulfate (PMS) are sluggish mass transfer kinetics and low intrinsic activity. Here, oxygen vacancies (Vo)-rich of CoO nanosheets were anchored on the superficies of spirulina-based reduced graphene oxide-konjac glucomannan (KGM) aerogel (R-CoO/SRGA). The porous structure and superhydrophilicity conferred by KGM maximized the diffusion and transport of reactant.

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In this study, the optimal hydrogen (H) production conditions of the high-efficiency H-producing mutant strain Ethanoligenens harbinense YR-3 (carbon-nitrogen ratio 5.5, phosphate buffer 80 mM, initial pH 6.0, biotin 1.

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The utilization of biochar-catalyzed peroxymonosulfate in advanced oxidation processes (BC-PMS AOPs) is widely acknowledged as an effective and economical method for mitigating emerging contaminants (ECs). Especially, state-of-the-art machine learning (ML) technology has been employed to accurately predict the reaction rate constants of EC degradation in BC-PMS AOPs, primarily focusing on three aspects: performance prediction, operating condition optimization, and mechanism interpretation. However, its real application in specific degradation optimization targeting different ECs is seldom considered, hindering the realization of contaminant-oriented BC-PMS AOPs.

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Bisphenol A, a hazardous endocrine disruptor, poses significant environmental and human health threats, demanding efficient removal approaches. Traditional biological methods struggle to treat BPA wastewater with high chloride (Cl) levels due to the toxicity of high Cl to microorganisms. While persulfate-based advanced oxidation processes (PS-AOPs) have shown promise in removing BPA from high Cl wastewater, their widespread application is always limited by the high energy and chemical usage costs.

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