Publications by authors named "Likui Feng"

Article Synopsis
  • * Hydrothermal treatment at varying temperatures affects the conversion of free water to bound water, with higher temperatures drastically reducing bound water content and sludge viscosity.
  • * The study highlights the importance of the hydrophobic/hydrophilic EPS ratio and demonstrates that targeting specific protein structures can enhance sludge dewaterability by reducing water-holding capacity.
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The addition of composite conductive materials is being increasingly recognized as a promising strategy to enhance anaerobic digestion (AD) performance. However, the influence of these materials on protein hydrolysis has been poorly documented. Here, a novel magnetic biochar derived from oil sludge and straw was synthesized using different iron sources and successfully applied in sludge AD.

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Pathogenic infection elicits behaviors that promote recovery and survival of the host. After exposure to the pathogenic bacterium Pseudomonas aeruginosa PA14, the nematode Caenorhabditis elegans modifies its sensory preferences to avoid the pathogen. Here, we identify antagonistic neuromodulators that shape this acquired avoidance behavior.

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The chemical characteristics of extracellular polymeric substances (EPS) of anammox bacteria (AnAOB) play a crucial role in the rapid enrichment of AnAOB and the stable operation of wastewater anammox processes. To clarify the influential mechanisms of sludge EPS on AnAOB aggregation, multiple parameters, including the polarity distribution, composition, and molecular structure of EPS, were selected, and their quantitative relationship with AnAOB aggregation was analyzed. Compared to typical anaerobic sludge (anaerobic floc and granular sludge), the anammox sludge EPS exhibited higher levels of tryptophan-like substances (44.

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Increasing occurrence of heavy metals (HMs) in sewage sludge threatens its widespread land utilization in China due to its potential impact on nutrient cycling in soil, requiring a better understanding of HM-induced impacts on nitrification. Herein, lab-scale experiments were conducted over 185-day, evaluating the effect of sludge-derived chromium (Cr), nickel (Ni), and lead (Pb) on soil nitrification at different concentrations. Quantitative polymerase chain reaction and linear regression results revealed an inhibitory sequence of gene abundance by HMs' labile fraction: ammonia-oxidizing bacteria (AOB)-ammonia monooxygenase (amoA)> nitrite oxidoreductase subunit alpha (nxrA)> nitrite oxidoreductase subunit beta (nxrB).

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Strengthening direct interspecies electron transfer (DIET), via adding conductive materials, is regarded as an effective way for improving methane productivity of anaerobic digestion (AD). Therein, the supplementation of combined materials (composition of biochar and iron-based materials) has attracted increasing attention in recent years, because of their advantages of promoting organics reduction and accelerating biomass activity. However, as far as we known, there is no study comprehensively summarizing the application of this kind combined materials.

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Metals pollution of lead in agricultural soils is a serious problem for food safety. Therefore, we investigated the toxic effects of carbonate-bound fraction Pb on agricultural soil from various aspects. The results revealed that a higher carbonate-bound fraction of Pb had more toxic effects on wheat growth, as evidenced by higher malondialdehyde (3.

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Low and unstable pollutant removal is regarded as the bottleneck problem in constructed wetlands (CWs) for wastewater treatment. This study investigated the effect of static magnetic field (MF) on enhancing the purification efficiency and microbial mechanism in vertical flow CW systems for treating domestic wastewater. The results showed that MF-CWs outperformed control systems in terms of treatment performance, with average removal efficiencies of COD, NH-N, TN, and TP reaching 92.

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Direct interspecies electron transfer (DIET) has been received tremendous attention, recently, due to the advantages of accelerating methane production via organics reduction during anaerobic digestion (AD) process. DIET-based syntrophic relationships not only occurred with the existence of pili and some proteins in the microorganism, but also can be conducted by conductive materials. Therefore, more researches into understanding and strengthening DIET-based syntrophy have been conducted with the aim of improving methanogenesis kinetics and further enhance methane productivity in AD systems.

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Antibiotics, the most frequently prescribed drugs, have been widely applied to prevent or cure human and veterinary diseases and have undoubtedly led to massive releases into sewer networks and wastewater treatment systems, a hotspot where the occurrence and transformation of antibiotic resistance take place. Extracellular polymeric substances (EPS), biopolymers secreted via microbial activity, play an important role in cell adhesion, nutrient retention, and toxicity resistance. However, the potential roles of sludge EPS related to the resistance and removal of antibiotics are still unclear.

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Short-chain fatty acids (SCFAs) recovery through anaerobic fermentation is a promising technology to achieve carbon-neutral in waste activated sludge (WAS) management. After 0.15 g CaO/g volatile suspended solids (VSS) addition and three-cycle freezing co-pretreatments, the maximal SCFAs production of 438.

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Four zero valent iron-based composites were prepared and applied as the reactive media of permeable reactive barriers. Batch tests and continuous-flow column experiments were conducted to assess the long-term performance of these composites for possible utilization as fillers for PRB. The experimental results of the batch tests revealed that in single-metal systems, the removal efficiency of Cu(Ⅱ), Co(Ⅱ), Cr(Ⅵ) and As(Ⅲ) could reach 98% at equilibrium.

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Polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) hybrid systems typically use complex protein-protein interactions to facilitate direct transfer of intermediates between these multimodular megaenzymes. In the canal-associated neurons (CANs) of Caenorhabditis elegans, PKS-1 and NRPS-1 produce the nemamides, the only known hybrid polyketide-nonribosomal peptides biosynthesized by animals, through a poorly understood mechanism. Here, we use genome editing and mass spectrometry to map the roles of individual PKS-1 and NRPS-1 enzymatic domains in nemamide biosynthesis.

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Quantitative characterization of dissolved organic matter (DOM) in various aquatic ecosystems has become of increasing importance as its transformation plays a key role in inland water carbon, yet few studies have quantified water DOM inputs to storage lakes for water quality control and safety assurance. This study assessed the quantity and quality of DOM in 21 inflow rivers of Nansi Lake as the important storage lake of large-scale water transfer projects by using excitation-emission matrix spectroscopy coupled with parallel factor analysis (EEM-PARAFAC) and ultraviolet-visible (UV-Vis) spectroscopy. The results showed that DOM contents varied significantly with an average value of 5.

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Constructed wetlands (CWs) by modifying operation strategies or substrates have grown in popularity in recent years for improving the treatment capacity. However, few studies focused on the responses of wetland vegetation and associated microorganisms in CWs for treating high-strength wastewaters. This study evaluated the long-term responses of plants and microbes in CWs with biochar and intermittent aeration for treating real swine wastewater.

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Vertical flow constructed wetlands are facing the problem of low removal efficiency when treating high-load wastewater. This study explored the effect of oxygen supplement (1.2, 1.

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Application of biochar can be an effective and low cost technique for wastewater treatment while reducing greenhouse gas emissions. In this study, biochar was used as substrates in Vertical flow constructed wetlands (VFCWs) for enhancing the removal of contaminant from low C/N wastewaters with different influent strengths. The removal of organic matter and nitrogen in biochar-added and non-biochar-added VFCWs with different low C/N influent strengths were evaluated systematically.

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produces ascaroside pheromones to control its development and behavior. Even minor structural differences in the ascarosides have dramatic consequences for their biological activities. Here, we identify a mechanism that enables to dynamically tailor the fatty-acid side chains of the indole-3-carbonyl (IC)-modified ascarosides it has produced.

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There is currently no consensus on the most suitable therapeutic approach for psoriasis (PS) co-existing with posthepatic cirrhosis (PCs) and hepatocellular carcinoma (HCC) following liver transplantation (LT). The present study provides an analysis of the therapeutic experience of such patients. Five LT recipients (two with PC and three with HCC) with accompanying PS were included.

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Objective To investigate the effect of psoralen combined with A-band ultraviolet (PUVA)-treated human spleen lymphocytes on the phenotype and function of immature dendritic cells (imDCs). Methods Human peripheral blood mononuclear cells (PBMCs) were isolated and induced to produce DCs by interleukin-4 (IL-4) and recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF). On the sixth day, the imDCs were obtained and stimulated by lipopolysaccharide (LPS).

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Objective To investigate whether lipopolysaccharide (LPS) can induce the maturation of immature dendritic cells (imDCs) which phagocytose apoptotic spleen lymphocytes. Methods Human peripheral blood mononuclear cells (PBMCs) were induced to produce DCs by interleukin 4 (IL-4) and recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF). Human spleen cells (hSPs) were isolated and treated with psoralen combined with ultraviolet A(PUVA) to obtain apoptotic PUVA-hSPs.

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Polyketides and nonribosomal peptides are two important types of natural products that are produced by many species of bacteria and fungi but are exceedingly rare in metazoans. Here, we elucidate the structure of a hybrid polyketide-nonribosomal peptide from Caenorhabditis elegans that is produced in the canal-associated neurons (CANs) and promotes survival during starvation-induced larval arrest. Our results uncover a novel mechanism by which animals respond to nutrient fluctuations to extend survival.

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Background: Lymphocyte subsets play important roles in rejection in liver transplant recipients, and the effect of splenic function on these roles remains unknown. The aim of this study was to explore the feasibility to adjust immunosuppressive agents based on splenic function status through detecting the lymphocyte subsets in liver transplantBeijing recipients.

Methods: The lymphocyte subsets of 49 liver transplant recipients were assessed in the 309th Hospital of Chinese People's Liberation Army between June 2014 and August 2015.

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L-Rhamnose is a common component of cell-wall polysaccharides, glycoproteins and some natural products in bacteria and plants, but is rare in fungi and animals. In the present study, we identify and characterize a biosynthetic pathway for dTDP-rhamnose in Caenorhabditis elegans that is highly conserved across nematode species. We show that RML-1 activates glucose 1-phosphate (Glc-1-P) in the presence of either dTTP or UTP to yield dTDP-glucose or UDP-glucose, respectively.

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Objective: To explore the impact of triple anti-tumor therapy based on thymosin α1 (Tα1) combined with Huaier granule(HG) and sirolimus on the level of serum alpha-fetoprotein (AFP) in rat models of liver cancer.

Methods: Ninety Sprague-Dawley rats were randomly divided into triple anti-tumor therapy group, Tα1 group, HG group, sirolimus group, positive control and blank control groups, with 15 rats in each group. Except the blank control group, the rats in the other groups were induced using diethylnitrosamine (DEN) to establish liver cancer models.

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