Publications by authors named "Xiaoli Chai"

73 Publications

A Phase 2 Study of Camrelizumab for Advanced Hepatocellular Carcinoma: Two-Year Outcomes and Continued Treatment beyond First RECIST-Defined Progression.

Liver Cancer 2021 Sep 30;10(5):500-509. Epub 2021 Jun 30.

Jiangsu Hengrui Pharmaceuticals Co., Ltd, Shanghai, China.

Introduction: In a multicenter, open-label, parallel-group, randomized, phase 2 study for pretreated advanced hepatocellular carcinoma (HCC), camrelizumab showed potent antitumor activity and acceptable safety profile. The aim of this report was to provide long-term data and evaluate potential benefit of treatment with camrelizumab beyond progression.

Methods: From November 15, 2016, to November 16, 2017, 217 patients received camrelizumab 3 mg/kg intravenously every 2 or 3 weeks. Treatment beyond first Response Evaluation Criteria in Solid Tumors (RECIST)-defined progression (TBP) with camrelizumab was allowed.

Results: At data cutoff of December 16, 2019 (>2 years after the last patient enrollment; median duration of follow-up, 13.2 months [IQR 5.7-25.8]), 14 (43.8%) of the 32 responses per blinded independent central review were ongoing. The median duration of response was not reached (range 2.5-30.5 + months). The ongoing response rates at 12, 18, and 24 months were 68.3% (95% confidence interval [CI] 47.7-82.2), 59.8% (95% CI 38.8-75.6), and 53.1% (95% CI 31.0-71.0), respectively. The median overall survival (OS) was 14.2 months (95% CI 11.5-16.3). The 18- and 24-month OS rates were 41.3% (95% CI 34.6-47.9) and 33.7% (95% CI 27.3-40.2), respectively. Of the 172 patients who experienced RECIST-defined progression per investigator, 102 received TBP, while 70 did not (non-TBP). The median OS was 16.9 months (95% CI 13.3-22.6) in the TBP group versus 9.4 months (95% CI 5.8-14.8) in the non-TBP group, and the 18- and 24-month OS rates were 47.5% (95% CI 37.3-56.9) versus 33.1% (95% CI 22.3-44.3) and 38.8% (95% CI 29.2-48.4) versus 23.2% (95% CI 13.8-34.1), respectively. No new safety signals of camrelizumab were observed.

Conclusions: With prolonged follow-up, camrelizumab continues to demonstrate the durable response and long survival in pretreated advanced HCC patients with manageable toxicities, especially in those who continued the treatment beyond first RECIST-defined progression.
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http://dx.doi.org/10.1159/000516470DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8527901PMC
September 2021

Effects of maternal sugar intake during pregnancy on allergies in offspring: A protocol for systematic review and meta-analysis.

Medicine (Baltimore) 2021 Oct;100(42):e27447

Department of Obstetrics and Gynecology, Xishui County People's Hospital, Hubei University of Science and Technology, Huanggang, Hubei, China.

Background: To our knowledge, there is no comprehensive evidence quantifying the plausibility of the association between maternal free sugar intake during pregnancy and the development of offspring's allergic diseases. Thus, this systematic review examines the weight of evidence for causality from cohort studies on the association between maternal free sugar intake during pregnancy and the development of allergies in offspring.

Methods: The present meta-analysis is prepared and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. We search PUBMED, Scopus, EMBASE, and Cochrane Library databases through October, 2021. All clinical trials to assess the efficacy of maternal sugar intake during pregnancy on allergies in offspring are considered eligible for analysis. The Comprehensive Meta-Analysis Software 2 program is used for statistical analyses of the pooled data. A P value < .05 is considered statistically significant. The outcome measure is development of allergic disease among offspring assessed by any method (parental history, doctor diagnosed, or questionnaire based).

Results: It is hypothesized that high free sugar consumption during pregnancy may be associated with the development of allergies in offspring.
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http://dx.doi.org/10.1097/MD.0000000000027447DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8542120PMC
October 2021

Novel micro-granular sludge process for highly efficient treatment of low-strength and low C/N ratio municipal wastewater.

Chemosphere 2022 Jan 20;287(Pt 3):132322. Epub 2021 Sep 20.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China. Electronic address:

A novel high-concentration powder bio-carrier (HPB) process was developed for the high-load treatment of low-strength municipal wastewater with low carbon/nitrogen (C/N) ratio (∼3). The powder carrier facilitated the rapid micro-granulation of sludge within 20 days and the average particle size increased rapidly from 47 μm to 210 μm. Accordingly, the concentration of mixed liquid volatile suspended solids (MLVSS) increased from 1.8 g/L to 4.3 g/L, which enabled the HPB process to maintain a short hydraulic retention time (HRT) of 3.6 h. Correspondingly, the high volumetric load of 0.4-1.3 kg chemical oxygen demand (COD)/(m∙d) and 0.12-0.24 kg total nitrogen (TN)/(m∙d) could be achieved and twice higher than those of conventional activated sludge process, e.g., anaerobic/anoxic/oxic process. The carrier-induced sludge granulation also significantly optimized the microbial structure, and the high-throughput sequencing revealed the increasing abundances of denitrifying bacteria and anammox bacteria, which was consistent with the nitrogen removal efficiency rising from 44.6% to 77.4%. Accordingly, the enhanced nitrogen removal could be achieved with TN of effluent steadily below 5 mg/L. Especially, the mass balance analysis on carbon and nitrogen further indicated the advantage of newly developed HPB process in carbon source saving for nitrogen removal. All the results are believed to suggest a promising strategy for the highly efficient treatment of low-strength municipal wastewater.
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http://dx.doi.org/10.1016/j.chemosphere.2021.132322DOI Listing
January 2022

Influential mechanism of water occurrence states of waste-activated sludge: specifically focusing on the roles of EPS micro-spatial distribution and cation-dominated interfacial properties.

Water Res 2021 Sep 27;202:117461. Epub 2021 Jul 27.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address:

The highly hydrated colloidal structure of waste-activated sludge (WAS) is the main obstacle of enhanced dewatering for sludge volume minimization. Extracellular polymeric substances (EPS) maintain the colloidal stability of bio-flocs in a three-dimensional matrix due to bindings with bivalent cations (i.e., Ca and Mg) and hydrophobic interactions. However, few studies specifically focused on the quantitative relationships among spatial distribution of EPS, microstructure of bio-flocs and fractions of bound water (e.g. vicinal water and interstitial water). Thus, there may be still some debates on whether and what extent of the lysis or flocculation of sludge flocs is optimal for the dewaterability improvement. This study applied the gradient addition of cation exchange resin (CER) to remove EPS-complexed cations and loosen the spatial distribution of EPS. Consequently, how the spatial extension of EPS layers with relief of complex cations influenced the particle size distribution, fractal dimension, interfacial free energy and water occurrence states of WAS was systematically investigated. The quartz crystal microbalance with dissipation (QCM-D) was also applied to analyze the water-EPS interactions with and without the presence of Ca and Mg. All the results confirmed that the dispersed EPS adhering layers led to the higher fractal dimension (D) but the lower space filling degree of bio-flocs. Also, the 4-fold reduction in the polar/acid-based interfacial free energy could be induced by the removal of cations from EPS matrix, which indicated the significant increase in hydrophobicity. Predictably, the fractions of vicinal water and interstitial water were dominated by the polar/acid-based interfacial free energy and pore structure of microbial aggregates, respectively, which were confirmed by the strong Pearson correlation (R>0.80, p-value<0.04). These findings are expected to provide the improved mechanistic insights into the relationship between water occurrence states and colloidal structure of WAS, and can serve as the basis for the optimal combination of various sludge conditioning approaches towards regulating aggregation states of bio-flocs.
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http://dx.doi.org/10.1016/j.watres.2021.117461DOI Listing
September 2021

Mechanism insights into polyhydroxyalkanoate-regulated denitrification from the perspective of pericytoplasmic nitrate reductase expression.

Sci Total Environ 2021 Feb 31;754:142083. Epub 2020 Aug 31.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address:

For enhanced biological nutrient removal (BNR) process, the polyhydroxyalkanoate (PHA) can be used as an eco-friendly internal as well as external substrate for regulating the growth of heterotrophic denitrifiers and promoting the denitrification process for deep nitrogen removal from wastewater. However, the exact mechanisms by which PHA impacts bacterial metabolism and affects the electron transfer of denitrification remain unknown. In this study, the in-depth mechanism investigation for PHA-mediated denitrification based on the jointly applied transcriptomic, proteomic and Western Blotting techniques was performed on a model denitrifier, Pseudomonas stutzeri. Results showed that PHA dramatically fostered the growth of Pseudomonas stutzeri, resulting in improved nitrate removal efficiency from 32.8% to 45.8%. Comparison of protein expression profiles indicated that PHA promoted the expression of enzyme NapB and NapA by approximately 10.34 and 20.01 times, respectively, which were both in charge of reduction from nitrate to nitrite. Based on transcriptional sequencing and Tandem Mass Tags, the correlation results also showed that differential proteins and genes with the same expression trend were positively correlated (R = 0.427, p-value<0.033). Western Blotting approach was further developed to confirm the up-regulated expression of target protein with the higher proportion of PHA in carbon source of the medium, which proved the reliability of proteomics results. All the findings presented here are believed to deepen the understanding of microbial mechanism about PHA-enhanced denitrification from the novel perspective of associated electron-transfer enzymatic proteins.
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http://dx.doi.org/10.1016/j.scitotenv.2020.142083DOI Listing
February 2021

Effectiveness of anti-PD-1 for hepatocellular carcinoma - Authors' reply.

Lancet Oncol 2020 06;21(6):e294

Department of Intervention, Hunan Cancer Hospital, Changsha, China.

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http://dx.doi.org/10.1016/S1470-2045(20)30285-0DOI Listing
June 2020

Critical review on dewatering of sewage sludge: Influential mechanism, conditioning technologies and implications to sludge re-utilizations.

Water Res 2020 Aug 10;180:115912. Epub 2020 May 10.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, 1239 Siping Road, Shanghai, 200092, China. Electronic address:

Sewage sludge (mainly composed of excessive bio-sludge) is an inevitable by-product of biological wastewater treatment process and contains various toxic substances, such as pathogens, heavy metals, and organic contaminants. The production of sewage sludge may cause serious pollution risks without appropriate disposals. As the essential step of sludge treatment, dewatering plays significant roles in minimizing the sludge volume, facilitating the transportation, increasing the calorific value and even reducing the leachate production in landfill sites. This paper presents a comprehensive review on the issues related to dewatering of sewage sludge. Section 1 starts with the environmental implications of sludge dewatering. Section 2 deals with the concepts and challenges about differentiation of bound water fractions, and also reviews the recent progress of in-situ visualization of water occurrence states in bio-flocs. Section 3 discusses about how various physiochemical properties influence the sludge dewaterability, and the insufficiency in in-situ micro-characterization of sludge constituents is pointed out. Section 4 reviews the existing conditioning technologies for sludge dewaterability improvement, and the advantages/disadvantages of each technology in terms of applicable occasions, material consumption, energy consumption and environmental impacts are evaluated. The last section (section 5) specifically analyzes the feasibility of integrating sludge dewatering and re-utilization, and raises attention to the potential environmental risks of dewatering conditioning. Based on the above discussion, we propose that a unified theory for sludge dewaterability improvement remains to be established. Especially, how the molecular structures of sludge compositions affect the solid-water interface behavior requires to be deepened, which will further unravel the mechanism behind strong water-holding capacities of bio-flocs. Additionally, we believe that the key challenges for sludge dewatering is how to select the appropriate conditioning technique according to the physiochemical properties of target sludge. The reliable indicators for real-time control of conditioning operations are still deficient, e.g., dynamic dosage control of conditioning chemicals. Accordingly, the potential environmental risks of excessive conditioning chemicals should be taken into more consideration.
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http://dx.doi.org/10.1016/j.watres.2020.115912DOI Listing
August 2020

Reactive cutaneous capillary endothelial proliferation in advanced hepatocellular carcinoma patients treated with camrelizumab: data derived from a multicenter phase 2 trial.

J Hematol Oncol 2020 05 11;13(1):47. Epub 2020 May 11.

Clinical Research & Development, Jiangsu Hengrui Medicine Co., Ltd, Shanghai, China.

Background: Association of immune-related adverse events with tumor response has been reported. Reactive cutaneous capillary endothelial proliferation (RCCEP) is the most common adverse event related to camrelizumab, an immune checkpoint inhibitor, but lack of comprehensive analyses. In this study, we conducted comprehensive analyses on RCCEP in advanced hepatocellular carcinoma (HCC) patients treated with camrelizumab monotherapy.

Methods: Data were derived from a Chinese nationwide, multicenter phase 2 trial of camrelizumab in pre-treated advanced HCC. The occurrence, clinicopathological characteristics, and prognostic value of RCCEP were analyzed.

Results: With a median follow-up of 12.5 months, 145 of the 217 camrelizumab-treated patients (66.8%) experienced RCCEP (all grade 1 or 2). RCCEP occurred on the skin surface, mainly on the skin surface of head, face, and trunk. RCCEP could be divided into 5 types including "red-nevus-like," "pearl-like," "mulberry-like," "patch-like," and "tumor-like," according to the morphological features. RCCEP biopsy and pathology showed capillary endothelial hyperplasia and capillary hyperplasia in dermis. Significant association between RCCEP occurrence with higher objective response rate was observed (19.3% vs. 5.6%; one-sided p = 0.0044). Compared with those without RCCEP, patients with RCCEP had prolonged progression-free survival (median PFS; 3.2 months vs. 1.9 months; one-sided p < 0.0001) and overall survival (median OS; 17.0 months vs. 5.8 months; one-sided p < 0.0001). In multivariable analyses, the development of RCCEP was significantly associated with prolonged PFS and OS after adjusting for baseline covariates. In addition, the landmark analyses of PFS and OS were consistent with the unadjusted analysis.

Conclusions: RCCEP occurred on the skin surface and was an immune response of skin capillary endothelial cells. RCCEP occurrence positively associated with outcomes of camrelizumab in advanced HCC.
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http://dx.doi.org/10.1186/s13045-020-00886-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7216554PMC
May 2020

Camrelizumab in patients with previously treated advanced hepatocellular carcinoma: a multicentre, open-label, parallel-group, randomised, phase 2 trial.

Lancet Oncol 2020 04 26;21(4):571-580. Epub 2020 Feb 26.

Jiangsu Hengrui Medicine, Shanghai, China.

Background: Blocking the interaction between PD-1 and its ligands is a promising treatment strategy for advanced hepatocellular carcinoma. This study aimed to assess the antitumour activity and safety of the anti-PD-1 inhibitor camrelizumab in pretreated patients with advanced hepatocellular carcinoma.

Methods: This is a multicentre, open-label, parallel-group, randomised, phase 2 trial done at 13 study sites in China. Eligible patients were aged 18 years and older with a histological or cytological diagnosis of advanced hepatocellular carcinoma, had progressed on or were intolerant to previous systemic treatment, and had an Eastern Cooperative Oncology Group performance score of 0-1. Patients were randomly assigned (1:1) to receive camrelizumab 3 mg/kg intravenously every 2 or 3 weeks, via a centralised interactive web-response system using block randomisation (block size of four). The primary endpoints were objective response (per blinded independent central review) and 6-month overall survival, in all randomly assigned patients who had at least one dose of study treatment. Safety was analysed in all treated patients. This study is registered with ClinicalTrials.gov, number NCT02989922, and follow-up is ongoing, but enrolment is closed.

Findings: Between Nov 15, 2016, and Nov 16, 2017, 303 patients were screened for eligibility, of whom 220 eligible patients were randomly assigned and among whom 217 received camrelizumab (109 patients were given treatment every 2 weeks and 108 every 3 weeks). Median follow-up was 12·5 months (IQR 5·7-15·5). Objective response was reported in 32 (14·7%; 95% CI 10·3-20·2) of 217 patients. The overall survival probability at 6 months was 74·4% (95% CI 68·0-79·7)]. Grade 3 or 4 treatment-related adverse events occurred in 47 (22%) of 217 patients; the most common were increased aspartate aminotransferase (ten [5%]) and decreased neutrophil count (seven [3%]). Two deaths were judged by the investigators to be potentially treatment-related (one due to liver dysfunction and one due to multiple organ failure).

Interpretation: Camrelizumab showed antitumour activity in pretreated Chinese patients with advanced hepatocellular carcinoma, with manageable toxicities, and might represent a new treatment option for these patients.

Funding: Jiangsu Hengrui Medicine.
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http://dx.doi.org/10.1016/S1470-2045(20)30011-5DOI Listing
April 2020

Effects of plant radial oxygen loss on methane oxidation in landfill cover soil: A simulative study.

Waste Manag 2020 Feb 24;102:56-64. Epub 2019 Oct 24.

School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, China.

Radial oxygen loss (ROL) by the spreading root systems of vegetation can improve soil aeration for subsequent oxidation of methane (CH) by microbes in landfill cover soils. This study proposes a theoretical model that elucidated the effects of ROL on microbial oxidation of CH to understand landfill gas transportation and oxidation in landfill cover soils. Parametric analyses were conducted to investigate the effects of root depth, root architecture, and ROL rate on the CH oxidation efficiency of landfill cover soils. The simulation results suggested that disregarding O emissions by plants root systems could underestimate the CH oxidation efficiency, especially when the water content ranged from 20% to 35%. Additionally, plants with a parabolic root architecture indicated 7-13% higher CH oxidation efficiency than other root architectures, i.e., uniform, triangular, and exponential. The CH oxidation efficiency increased rapidly at root depths less than 0.25 m. Therefore, plants characterized by a parabolic root architecture, longer root length, and higher ROL capacity should be selected as the preferred species for mitigating CH emissions from landfills in humid areas.
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http://dx.doi.org/10.1016/j.wasman.2019.10.033DOI Listing
February 2020

Effect of temperature on tertiary nitrogen removal from municipal wastewater in a PHBV/PLA-supported denitrification system.

Environ Sci Pollut Res Int 2019 Sep 13;26(26):26893-26899. Epub 2019 Jul 13.

College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.

In this study, a poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(lactic acid) (PHBV/PLA)-supported denitrification system was built to remove nitrogen from municipal wastewater treatment plant secondary effluent, and the influence of operating temperature on nitrogen removal was further investigated. Results indicated that a PHBV/PLA-supported denitrification system could effectively fulfill the tertiary nitrogen removal. The nitrogen removal efficiency gradually declined with the operating temperature decreasing, and the denitrification rate at 30 °C was 5 times higher than that at 10 °C. Meanwhile, it was found that a slight TOC accumulation only occurred at 30 °C (with an average of 2.03 mg/L) and was avoided at 10~20 °C. The reason for effluent TOC variation was further explained through the consumption and generation pathways of TOC in this system. Furthermore, the temperature coefficient was about 0.02919, indicating that the PHBV/PLA-supported denitrification system was a little sensitive to temperature. A better knowledge of the effect of operating temperature will be significant for the practical application of the solid-phase denitrification system.
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http://dx.doi.org/10.1007/s11356-019-05823-6DOI Listing
September 2019

Impairing the maintenance of germinative cells in Echinococcus multilocularis by targeting Aurora kinase.

PLoS Negl Trop Dis 2019 05 16;13(5):e0007425. Epub 2019 May 16.

State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China.

Background: The tumor-like growth of the metacestode larvae of the tapeworm E. multilocularis causes human alveolar echinococcosis, a severe disease mainly affecting the liver. The germinative cells, a population of adult stem cells, are crucial for the larval growth and development of the parasite within the hosts. Maintenance of the germinative cell pools relies on their abilities of extensive proliferation and self-renewal, which requires accurate control of the cell division cycle. Targeting regulators of the cell division progression may impair germinative cell populations, leading to impeded parasite growth.

Methodology/principal Findings: In this study, we describe the characterization of EmAURKA and EmAURKB, which display significant similarity to the members of Aurora kinases that are essential mitotic kinases and play key roles in cell division. Our data suggest that EmAURKA and EmAURKB are actively expressed in the germinative cells of E. multilocularis. Treatment with low concentrations of MLN8237, a dual inhibitor of Aurora A and B, resulted in chromosomal defects in the germinative cells during mitosis, while higher concentrations of MLN8237 caused a failure in cytokinesis of the germinative cells, leading to multinucleated cells. Inhibition of the activities of Aurora kinases eventually resulted in depletion of the germinative cell populations in E. multilocularis, which in turn caused larval growth inhibition of the parasite.

Conclusions/significance: Our data demonstrate the vital roles of Aurora kinases in the regulation of mitotic progression and maintenance of the germinative cells in E. multilocularis, and suggest Aurora kinases as promising druggable targets for the development of novel chemotherapeutics against human alveolar echinococcosis.
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http://dx.doi.org/10.1371/journal.pntd.0007425DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6541280PMC
May 2019

Effect of soil types and ammonia concentrations on the contribution of ammonia-oxidizing bacteria to CH oxidation.

Waste Manag Res 2019 Jul 26;37(7):698-705. Epub 2019 Apr 26.

1 State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, China.

Irrigation of stabilized landfill leachate to landfill cover soil is a cost-effective operation for leachate treatment. The contribution of ammonia-oxidizing bacteria (AOB) in the cover soil to CH oxidation, however, is unclear, because AOB and methane-oxidizing bacteria (MOB) can co-oxidize CH and NH-N. Thus, the contribution of AOB and the inhibitory effect of NH-N to CH oxidation were determined by using an acetylene pretreatment discrimination method. The results showed that the contributions of AOB to CH oxidation varied with the soil type and the concentration of NH-N addition. The relative contribution of AOB to CH oxidation for compost without NH-N addition was the highest (65.0%), and was 2.5 and 3.4 times higher than the corresponding values for aged refuse and landfill cover soil, respectively. The inhibitory effect of NH-N was enhanced by increasing the concentration of NH-N addition for all the soil samples. At equal NH-N addition concentrations, the inhibitory effect was always the lowest for the compost sample. The abundances of particulate methane monooxygenase () and ammonia monooxygenase () genes were key factors influencing the CH oxidation rate and contribution of AOB to CH oxidation. The higher abundance of and lower abundance of in landfill cover soil could explain the higher CH oxidation rate and lower contribution of AOB to CH oxidation in this soil type. Meanwhile, the higher contribution of AOB to CH oxidation for compost could be attributed to the higher abundance of the gene and lower abundance of .
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http://dx.doi.org/10.1177/0734242X19843988DOI Listing
July 2019

Unraveling the water states of waste-activated sludge through transverse spin-spin relaxation time of low-field NMR.

Water Res 2019 May 25;155:266-274. Epub 2019 Feb 25.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.

The physical states of water are crucial for the dewatering efficiency of waste-activated sludge (WAS). However, to date, there is still lack of promising methods for the distinct differentiation of water states in colloidal microbial aggregates. This study proposed that the transverse spin-spin relaxation time (T) distribution of low-field nuclear magnetic resonance (NMR) could be a useful tool to unravel the occurrence state of water in WAS. Due to the different interaction strengths of protons with the surrounding environment, the three water states with different T ranges were identified. The water strongly trapped on the surface of solid phase through hydrogen bound could be classified as vicinal water; interstitial water refers to the water physically trapped in bio-floc by steric hindrance or adsorption; and the water that is least affected by solid compositions is categorized as moderately mobile water. The potential ways of typical conditioning approaches for shifting water states were also investigated. The removal of hydrophilic compounds in extracellular polymeric substances (EPS) and surface charge neutralization were both found to be possible ways to influence the percentage of vicinal water (Pearson correlation coefficient R > 0.950, p-value ≤ 0.05). The disintegration or compaction of colloidal microbial aggregates could induce the transformation of interstitial water into moderately mobile water. All the above results are believed to deepen the mechanism insights into the differentiation and interactive transformation of water states in bio-floc of WAS.
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http://dx.doi.org/10.1016/j.watres.2019.02.031DOI Listing
May 2019

Free-conditioning dewatering of sewage sludge through in situ propane hydrate formation.

Water Res 2018 11 28;145:464-472. Epub 2018 Aug 28.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.

The propane hydrate formation was proposed to have potentials in realizing free-conditioning dewatering of sewage sludge with implications to simultaneous clean water extraction and highly efficient volume reduction. Primarily, the investigation on phase equilibrium of propane hydrates found that the organic components of sewage sludge promoted the propane hydrate formation in terms of decreasing equilibrium pressure by up to 19.2%, compared with that in pure water. Further, the feasibility of hydrate-based dewatering was verified through the observation of propane hydrate formation in sewage sludge and also the quality analysis of water generated from decomposition of up-floated formed hydrates. The formation of up-floated propane hydrates extracted water molecules from sewage sludge into homogeneous crystal phase, which actually excluded sludge particles from hydrate phase and realized the reduction of water in sludge phase. The efficiency of water conversion into hydrates was determined by monitoring propane pressure, which indicated that 14 batch runs decreased the water content of sludge from 98.81wt.% to 44.3wt.% under free-conditioning conditions. The chemical oxygen demand, total nitrogen and total phosphorus of hydrate-extracted water were measured to be 21 ± 1 mg/L, 10.5 ± 0.2 mg/L and 0.4 ± 0 mg/L, respectively, which reflected the excellent separation performance and also indicated that the hydrate-extracted water can be directly discharged without further treatments. Finally, the unit energy consumption of hydrate-based dewatering process based on a continuous operation mode was calculated to be 2673.96 kW h/t dry solid of sewage sludge, which was nearly half of that in thermal drying process. Therefore, the propane hydrate-based process is believed to maximize the green operation of enhanced sludge dewatering while minimizing the energy and additional material consumption.
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http://dx.doi.org/10.1016/j.watres.2018.08.057DOI Listing
November 2018

Temporal variation of vegetation at two operating landfills and its implications for landfill phytoremediation.

Environ Technol 2020 Feb 22;41(5):649-657. Epub 2018 Sep 22.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, PR People's Republic of China.

Landfilling is a popular method to dispose of solid waste around the world, but this practice is associated with inevitable negative consequences such as air and water pollution and potential health hazards. Phytoremediation is an economical and promising technology to address these problems. To select suitable species for restoring landfills in China, the vegetation characteristics and their physiological activities were investigated in two different landfills. The results showed that the vegetation coverage of the two landfills both increased with the closure time. The species diversity decreased with the closure time in the Chongming landfill, whereas it showed the opposite trend in the Jiangcungou landfill. Five dominant species (, , , , and ) and four dominant species (, , , and ) were identified in the Chongming landfill and Jiangcungou landfill, respectively, and these dominant species were mainly annual plants. In addition, the net photosynthetic rate of and was the highest in the Chongming landfill and Jiangcungou landfill, respectively. Their photosynthetic rates were influenced significantly by stomatal conductance. Based on the overall results, among the dominant species identified, and represent potentially well suited plants to use in the remediation of landfills in China, because of their strong adaptability to landfill environments and natural occurrence in landfills.
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http://dx.doi.org/10.1080/09593330.2018.1508253DOI Listing
February 2020

Sequestration of Sulphide from Biogas by thermal-treated iron nanoparticles synthesized using tea polyphenols.

Environ Technol 2020 Feb 20;41(6):741-750. Epub 2018 Aug 20.

The State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, People's Republic of China.

Dark tea-iron nanoparticles (DT-Fe NPs) were prepared using extracts of dark tea leaves as a reducing agent, and further underwent thermal treatment in air. The HS removal performances of thermal-treated DT-Fe NPs for biogas were further evaluated using a custom-designed fixed-bed reactor (reaction temperature of 250°C, HS content of 1%). Significant morphology and chemical composition differences were observed when DT-Fe NPs were treated at different temperatures (300-800C). X-ray diffractometer analysis revealed that a phase transition from γ-FeO to α-FeO occurred under heat treatment. When the thermal treatment temperature was 300°C, only α-FeO was detected. Both α-FeO and γ-FeO were present in the sample treated at 400°C. When the thermal treatment temperature was 500-800°C, γ-FeO in the sample was completely converted to α-FeO. The HS removal capacity is 14.72 mg HS/g for DT-Fe NPs without treatment. However, the value increased significantly to 408.30 mg HS/g after 400°C thermal treatment, which can be explained by the formation of highly active γ-FeO. The reaction product of thermal-treated DT-Fe NPs at 400°C and HS were further characterized by X-ray diffractometer and X-ray photoelectron spectroscopy. The results showed that it is composed of FeS and FeS, in which 72.6% of the sulphur existed as disulphide and 27.4% as monosulphide.
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http://dx.doi.org/10.1080/09593330.2018.1509891DOI Listing
February 2020

Methylmercury levels in cover soils from two landfills in Xi'an and Shanghai, China: Implications for mercury methylation potentials.

Waste Manag 2018 Aug 22;78:331-336. Epub 2018 Jun 22.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, PR China. Electronic address:

Landfills are considered important sources of mercury for surrounding ecosystems. Methylmercury (MeHg) levels in waste layers have been studied extensively; however, the levels of MeHg in cover soils remain undefined. Here, total mercury (THg) and MeHg concentrations in surface cover soils and soil cores from two landfills in China and possible factors affecting Hg methylation were studied. The mean MeHg concentration in surface cover soils from both landfills was 0.048 ng g, suggesting that cover soil layers are not active sites of MeHg production. Soil MeHg concentrations in both landfills were affected little by closure time. In the Jiangcungou landfill, no correlations between MeHg concentration and the measured environmental factors (e.g., THg, soil pH, organic matter (OM), and S) were observed that indicated that these parameters might have indirect effects on MeHg concentration. However, in the Laogang landfill, significant correlations were found between MeHg concentration and the measured environmental factors. The results showed that MeHg concentration in the surface cover soil from area D of the Laogang landfill is regulated mainly by soil pH, OM, and S, and that its vertical distribution in areas C and D is regulated mainly by soil pH and soil OM, respectively. These findings fill a knowledge gap regarding MeHg levels in cover soils and they advance our understanding of Hg cycling in landfills, presenting positive implications for landfill management and risk assessment of MeHg.
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http://dx.doi.org/10.1016/j.wasman.2018.06.008DOI Listing
August 2018

Mechanism insights into bio-floc bound water transformation based on synchrotron X-ray computed microtomography and viscoelastic acoustic response analysis.

Water Res 2018 10 5;142:480-489. Epub 2018 Jun 5.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China. Electronic address:

This study visually tracked the micro-spatial water distribution in bio-flocs of waste activated sludge through in situ synchrotron X-ray computed microtomography. Primarily, the two fractions of bound water, the vicinal water adhering to the surface of organic compositions and the interstitial water mechanically trapped in the net-like structure of bio-flocs, were proposed based on the cross-section imaging results. Furthermore, the determinants on bound water occurrences were explored in terms of viscoelastic acoustic responses of extracellular polymeric substances (EPS). The joint roles of hydrophilic substance removal, EPS aggregation compaction and colloidal instability of sludge flocs in bound water reduction were confirmed by the strong correlations (Pearson correlation coefficient, R > 0.95, p-value<0.04) among protein levels of EPS, EPS viscosity and bound water contents. Accordingly, providing adhering sites for vicinal water and forming bio-flocs with high viscosity for trapping interstitial water were proposed to be the contributions of EPS on bound water occurrences.
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http://dx.doi.org/10.1016/j.watres.2018.06.003DOI Listing
October 2018

A Simulation model for estimating methane oxidation and emission from landfill cover soils.

Waste Manag 2018 Jul 27;77:426-434. Epub 2018 Apr 27.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China. Electronic address:

Quantification of methane (CH) oxidation and emission from landfill cover soils is important for evaluating measures to mitigate anthropogenic greenhouse gas emissions. In this study, a model that combines the multicomponent diffusive equation and Darcy's law, coupled with the dual Monod kinetic equation, was established to simulate CH transport, oxidation and emission in landfill cover soils. Sensitivity analysis was performed to illustrate the influence of model parameters on CH transport, oxidation and emission. The model was then applied to predict CH emissions from several column experiments. The results of the sensitivity analysis showed that a high CH oxidation rate can be obtained with a high V of cover soil, even for a low cover soil thickness, and that oxidation efficiency is constant when the thickness of the cover soil becomes greater than a threshold value. The simulated results fitted well with the measured values, confirming that the new model provides a reliable method for estimating CH emissions from landfills.
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http://dx.doi.org/10.1016/j.wasman.2018.04.029DOI Listing
July 2018

Effect of different carbon sources on denitrification performance, microbial community structure and denitrification genes.

Sci Total Environ 2018 Sep 5;634:195-204. Epub 2018 Apr 5.

College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address:

Solid and liquid organic substances as carbon sources for denitrification process were deeply explored. In this study, the effect of three carbon sources, referred to as poly (3-hydroxybutyrate-co-3-hydroxyvalerate)/poly (lactic acid) (PHBV/PLA) polymer, glucose and CHCOONa, on denitrification performance, microbial community and functional genes were investigated. It was found that maximum denitrification rates of 0.37, 0.46 and 0.39gN/(L·d) were achieved in PHBV/PLA, glucose and CHCOONa supported denitrification systems, respectively. Meanwhile, Illumina MiSeq sequencing revealed that three carbon sources led to different microbial community structures. It can be seen that Brevinema/Thauera/Dechloromonas, Tolumonas/Thauera/Dechloromonas, Thauera dominated in the PHBV/PLA, glucose and CHCOONa supported denitrification systems, respectively. Transcriptome-based analysis further indicated that the glucose supported denitrification system showed the highest FPKM values (the fragments per kilobase per million mapped reads) of the genes participating in the dissimilatory nitrate reduction process, corresponding to the greatest effluent NH-N concentration. A better knowledge of effect of different carbon sources on denitrification process will be significant for nitrate removal in practice.
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http://dx.doi.org/10.1016/j.scitotenv.2018.03.348DOI Listing
September 2018

Methane emissions from landfill: influence of vegetation and weather conditions.

Environ Technol 2019 Jul 22;40(16):2173-2181. Epub 2018 Feb 22.

a State Key Laboratory of Pollution Control and Resource Reuse, Tongji University , Shanghai , People's Republic of China.

Vegetation plays an important role in CH transport and oxidation in landfill cover soil. This study investigated CH emission fluxes in two landfills with different surface coverage conditions and it found that the CH emission fluxes presented spatial and temporal disparities. A significant discrepancy in CH emission flux between day and night in areas covered with indicated that enhanced diffusion induced by rising temperature was the main mechanism for CH transport during daytime. A significant increase of CH emission flux after the and plants were cut indicated that these plants provide greater contributions to CH oxidation than to CH transport. Diel CH emission flux was found closely correlated with the climatic conditions. Diffusion was determined as the main mechanism for CH transport at daytime in bare area, mediated by solar radiation and air temperature. Diffusion and plant-mediated transport by convection was established as the main transport mechanism in areas covered with . Our results further the understanding of both the CH emission mechanism and the impact of vegetation on CH oxidation, transport, and emission, which will benefit the development of a reliable model for landfill CH emissions.
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http://dx.doi.org/10.1080/09593330.2018.1439109DOI Listing
July 2019

PHBV polymer supported denitrification system efficiently treated high nitrate concentration wastewater: Denitrification performance, microbial community structure evolution and key denitrifying bacteria.

Chemosphere 2018 Apr 8;197:96-104. Epub 2018 Jan 8.

College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address:

Biodegradable polymer supported denitrification (BPD) system shows good denitrification performance for the wastewater with low nitrate concentrations. In this study, a BPD system using Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) polymer as carbon source was developed to treat the wastewater with high nitrate concentrations. The denitrification performance, utilization ratio of PHBV polymers, and microbial community structure evolution and key denitrifying bacteria were comprehensively studied. Results indicated that an average nitrate removal efficiency of 99% could be achieved with an influent NO-N concentration of 100 mg L and a hydraulic retention time (HRT) of 7.25 h. Mass balance model predicted that 80% of the PHBV polymers were consumed by denitrifying bacteria, close to 72% consumption in real condition, suggesting the model might be useful for PHBV polymers management in BPD system. Further, the bacterial community structures varied along the bioreactor profile, which closely linked to the concentration profiles of nitrate and ammonia. Metatranscriptomic analysis identified the key denitrifying bacteria as Comamonas, Acidovorax and Dechloromonas. The PHBV supported denitrification system developed in this study shows potential for removal of high concentration of nitrate from wastewater.
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http://dx.doi.org/10.1016/j.chemosphere.2018.01.023DOI Listing
April 2018

A simulation model for methane emissions from landfills with interaction of vegetation and cover soil.

Waste Manag 2018 Jan 16;71:267-276. Epub 2017 Oct 16.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China. Electronic address:

Global climate change and ecological problems brought about by greenhouse gas effect have become a severe threat to humanity in the 21st century. Vegetation plays an important role in methane (CH) transport, oxidation and emissions from municipal solid waste (MSW) landfills as it modifies the physical and chemical properties of the cover soil, and transports CH to the atmosphere directly via their conduits, which are mainly aerenchymatous structures. In this study, a novel 2-D simulation CH emission model was established, based on an interactive mechanism of cover soil and vegetation, to model CH transport, oxidation and emissions in landfill cover soil. Results of the simulation model showed that the distribution of CH concentration and emission fluxes displayed a significant difference between vegetated and non-vegetated areas. CH emission flux was 1-2 orders of magnitude higher than bare areas in simulation conditions. Vegetation play a negative role in CH emissions from landfill cover soil due to the strong CH transport capacity even though vegetation also promotes CH oxidation via changing properties of cover soil and emitting O via root system. The model will be proposed to allow decision makers to reconsider the actual CH emission from vegetated and non-vegetated covered landfills.
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http://dx.doi.org/10.1016/j.wasman.2017.10.013DOI Listing
January 2018

Co-composting of municipal solid waste mixed with matured sewage sludge: The relationship between NO emissions and denitrifying gene abundance.

Chemosphere 2017 Dec 21;189:581-589. Epub 2017 Sep 21.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.

Aerobic composting is an alternative measure to the disposal of municipal solid waste (MSW). However, it produces nitrous oxide (NO), a highly potent greenhouse via microbial nitrification and denitrification. In this study, the effects of matured sewage sludge (MSS) amendment on NO emissions and the inter-relationships between NO emissions and the abundance of denitrifying bacteria were investigated during aerobic composting of MSW. The results demonstrated that MSW composting with MSS amendments (C1, and C2, with a MSW to MSS ratio of 2:1 and 4:1, (v/v), respectively) significantly increased NO emissions during the initial stage, yet contributed to the mitigation of NO emissions during the cooling and maturation stage. MSS amended composting emitted a total of 18.4%-25.7% less NO than the control treatment without MSS amendment (CK). Matured sewage sludge amendment also significantly altered the abundance of denitrifying bacteria. The quantification of denitrifying functional genes revealed that the NO emission rate had a significant positive correlation with the abundance of the nirS, nirK genes in both treatments with MSS amendment. The nosZ/(nirS + nirK) ratio could be a good indicator for predicting NO emissions. The higher NO emission rate during the initial stage of composting mixed with MSS was characterized by lower nosZ/(nirS + nirK) ratios, compared to CK treatment. Higher ratios of nosZ/(nirS + nirK) were measured during the cooling and maturation stage in treatments with MSS which resulted in a reduction of the NO emissions. These results demonstrated that MSS amendment could be a valid strategy for mitigating NO emissions during MSW composting.
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http://dx.doi.org/10.1016/j.chemosphere.2017.09.070DOI Listing
December 2017

Exchange pattern of gaseous elemental mercury in landfill: mercury deposition under vegetation coverage and interactive effects of multiple meteorological conditions.

Environ Sci Pollut Res Int 2017 Dec 26;24(34):26586-26593. Epub 2017 Sep 26.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, Republic of China.

Landfill is known as a potential source of atmospheric Hg and an important component of the local or regional atmospheric Hg budget. This study investigated the gaseous elemental Hg surface-air fluxes under differing conditions at a typical municipal solid waste landfill site, highlighting the interactive effects of plant coverage and meteorological conditions. The results indicated that Hg fluxes exhibited a feature represented by diel variation. In particular, Hg deposition was observed under a condition of Kochia sieversiana coverage, whereas emission that occurred after K. sieversiana was removed. Hg emission was the dominant mode under conditions of Setaria viridis coverage and its removal; however, the average Hg emission flux with the S. viridis coverage was nearly four times lower than after its removal. These findings verified that the plant coverage should be a key factor influencing the Hg emission from landfills. In addition, Hg fluxes were correlated positively with solar radiation and air/soil temperature and correlated inversely with relative humidity under all conditions, except K. sieversiana coverage. This suggested that the interactive effects of meteorological conditions and plant coverage played a jointly significant role in the Hg emission from landfills. It was established that K. sieversiana can inhibit Hg emission efficiently, and therefore, it could potentially be suitable for use as a plant-based method to control Hg pollution from landfills.
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http://dx.doi.org/10.1007/s11356-017-0275-9DOI Listing
December 2017

Occurrence State and Molecular Structure Analysis of Extracellular Proteins with Implications on the Dewaterability of Waste-Activated Sludge.

Environ Sci Technol 2017 Aug 7;51(16):9235-9243. Epub 2017 Aug 7.

College of Engineering and Applied Science, Stony Brook University , 100 Nicolls Road, Stony Brook, New York 11794, United States.

The occurrence state and molecular structure of extracellular proteins were analyzed to reveal the influencing factors on the water-holding capacities of protein-like substances in waste-activated sludge (WAS). The gelation process of extracellular proteins verified that advanced oxidation processes (AOPs) for WAS dewaterability improvement eliminated the water affinity of extracellular proteins and prevented these macromolecules from forming stable colloidal aggregates. Isobaric tags for relative and absolute quantitation proteomics identified that most of the extracellular proteins were originally derived from the intracellular part and the proteins originally located in the extracellular part were mainly membrane-associated. The main mechanism of extracellular protein transformation during AOPs could be represented by the damage of the membrane or related external encapsulating structure and the release of intracellular substances. For the selected representative extracellular proteins, the strong correlation (R > 0.97, p < 0.03) between the surface hydrophilicity index and α-helix percentages in the secondary structure indicated that the water affinity relied more on the spatial distribution of hydrophilic functional groups rather than the content. Destructing the secondary structure represented by the α-helix and stretching the polypeptide aggregation in the water phase through disulfide bond removal might be the key to eliminating the inhibitory effects of extracellular proteins on the interstitial water removal from WAS.
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http://dx.doi.org/10.1021/acs.est.7b02861DOI Listing
August 2017

Ecosystem activation system (EAS) technology for remediation of eutrophic freshwater.

Sci Rep 2017 07 6;7(1):4818. Epub 2017 Jul 6.

State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.

Ecosystem activation system (EAS) was developed to create beneficial conditions for microbiome recovery and then restore and maintain the ecological integrity (microbial community, phytoplankton, zooplankton) for eutrophic freshwater rehabilitation. A 30 day's filed test of EAS indicated that over 50% of contaminant was removed and the algae visibly disappeared. EAS treatment 2.5-fold increased the diversity of microbial community and changed the microbial community structure (e.g., two and three-fold decrease in the amount of Flavobacterium and Pseudomonas, typical abundant species of eutrophic freshwater, respectively). Further, the diversity of phytoplankton and zooplankton of treated water suggested that these species were diverse. Representative phytoplankton of eutrophic freshwater, Chlorella and Chlamydomonas were undetectable. The possible mechanism of EAS is restoring the trophic levels of the water body via bottom-up approach by microbial community.
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http://dx.doi.org/10.1038/s41598-017-04306-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5500588PMC
July 2017

Simultaneous enhancement of sludge dewaterability and removal of sludge-borne heavy metals through a novel oxidative leaching induced by nano-CaO.

Environ Sci Pollut Res Int 2017 Jul 24;24(19):16263-16275. Epub 2017 May 24.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai, 200092, China.

The production of sewage sludge with the presence of various contaminants has been a serious issue for the operation of wastewater treatment plants on both the economical and environmental sides. To minimize the sludge volume to be handled and limit the potential environmental risk, this study developed a novel oxidative leaching process for enhanced sewage sludge dewatering and simultaneous removal of heavy metals based on nano-CaO. Response surface methodology determined the following optimal conditioning parameters in terms of capillary suction time reduction: 0.0906 g/g dry solid (DS) nano-CaO, 0.9969 mmol/g DS Fe, and pH of 5.59. The speciation partitioning analysis of the heavy metals pre and post nano-CaO peroxidation indicated that the content of organically bound metals decreased and the percentage of soluble fraction increased substantially, which was beneficial for the removal of heavy metals through the dewatering unit. Nano-CaO peroxidation could also induce the transformation of extracellular polymeric substances (EPS) from the tightly bound layers to the loosely bound layers of sewage sludge flocs. Through the decline of the Ryan-Weber constant of fluorescence titration and the pseudo-first-order kinetic constant of complexation, it was verified that the binding capacity of EPS with metal ions could be damaged by nano-CaO peroxidation, which was the primary mechanism behind the substantial reduction of organically bound metals. This study is believed to provide novel insights into the application of nanotechnology in terms of the simultaneous volume and toxicity reduction of sewage sludge. Graphical abstract.
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http://dx.doi.org/10.1007/s11356-017-9261-5DOI Listing
July 2017

Identification of EmSOX2, a member of the Sox family of transcription factors, as a potential regulator of Echinococcus multilocularis germinative cells.

Int J Parasitol 2017 09 17;47(10-11):625-632. Epub 2017 May 17.

State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China. Electronic address:

Larvae of the tapeworm Echinococcus multilocularis cause alveolar echinococcosis (AE), one of the most lethal helminthic infections in humans. The germinative cells, a population of stem cell-like cells, are considered to drive the continuous growth of the metacestodes within the host. The mechanisms and relative molecules controlling the behavior of germinative cells are poorly understood. Sox transcription factors play important roles in maintenance and regulation of stem/progenitor cells. We here describe the identification of a Sox family member in E. multilocularis, EmSOX2, as a potential regulator of germinative cells. Replacement of mouse Sox2 with EmSox2 could derive induced pluripotent stem cells (iPSCs) from somatic cells, suggesting that EmSOX2 is functionally related to mammalian SOX2. EmSOX2 is actively expressed in the proliferating germinative cells in E. multilocularis, and is significantly downregulated upon specific depletion of the germinative cell population by hydroxyurea treatment. These findings suggest that EmSOX2 may play a critical role in regulating E. multilocularis germinative cells.
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http://dx.doi.org/10.1016/j.ijpara.2017.03.005DOI Listing
September 2017
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