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1.
J Hazard Mater ; : 127764, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34799165

RESUMO

Antibiotics can be biodegraded in activated sludge via co-metabolism and metabolism. In this study, we investigated the biodegradation pathways of sulfamethoxazole (SMX) and antibiotic resistant genes' (ARGs) fate in different autotrophic and heterotrophic microorganisms, by employing aerobic sludge, mixed sludge, and nitrifying sludge. A threshold concentration of SMX activating the degradation pathways in the initial stage of antibiotics degradation was found and proved in different activated sludge systems. Heterotrophic bacteria played an important role in SMX biodegradation. However, ammonia-oxidizing bacteria (AOB) had a faster metabolic rate, which was about 15 times higher than heterotrophic bacteria, contributing much to SMX removal via co-metabolism. As SMX concentration increases, the amoA gene and AOB relative abundance decreased in aerobic sludge due to the enrichment of functional heterotrophic bacteria, while it increased in nitrifying sludge. Microbial community analysis showed that functional bacteria which possess the capacity of SMX removal and antibiotic resistance were selected by SMX pressure. Potential ARGs hosts could increase their resistance to the biotoxicity of SMX and maintain system performance. These findings are of practical significance to guide antibiotic biodegradation and ARGs control in wastewater treatment plants.

2.
Ann Transl Med ; 9(12): 1022, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34277822

RESUMO

Background: To explore the specific prognosis related microRNAs (miRNAs) of glioma. Methods: The miRNA-Seq data and clinical information of glioma patients were downloaded from the TCGA (510 cases) and GEO (GSE112009, 25 cases) database. LASSO & COX regression was used to develop a miRNA-based model for predicting patient survival in the training set (n=255), to carry out glioma prognostic related miRNAs screening, and to construct a linear risk model based on the expression profiles of seven miRNAs. COX regression analysis was used to determine whether the miRNAs risk model was an independent prognostic factor. Results: Seven survival-related miRNAs (miR-140-5p, miR-145-5p, miR-148a-3p, miR-183-5p, miR-222-3p, miR-223-3p, and miR-374a-5p) were identified in the training set. This showed that the overall survival time of the high-risk group was significantly lower than that of the low-risk group in the training set, prediction set, and validation set (P<0.05). Further analysis revealed that age and Karnofsky score both affected the risk of glioma. By crossing seven potential target genes of microRNAs, 620 effective target genes were obtained and GO analysis showed that these were related to the positive regulation of cell migration, neuron migration, and the response of transforming growth factor, and KEGG analysis showed they were related to the TGF-beta signaling pathway, MAPK signaling, and AGE-RAGE signaling pathway in diabetic complications. Conclusions: Seven miRNAs which regulate target genes to participate in related signaling pathways and lead to a poor prognosis were identified as biomarkers of glioma.

3.
J Hazard Mater ; 419: 126508, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34323729

RESUMO

Anaerobic wastewater treatment is a promising technology for refractory pollutant treatment. The nano zero-valent iron (nZVI) assisted anaerobic system could enhance contaminant removal. In this work, we added nZVI into an anaerobic system to investigate the effects on system performances and metabolic mechanism for chloramphenicol (CAP) wastewater treatment. As nZVI concentrations increased from 0 to 1 g/L, the CAP removal efficiency was appreciably improved from 46.5% to 99.2%, while the CH4 production enhanced more than 20 times. The enhanced CAP removal resulted from the enrichments of dechlorination-related bacteria (Hyphomicrobium) and other functional bacteria (e.g., Zoogloea, Syntrophorhabdus) associated with refractory contaminants degradation. The improved CH4 production was ascribed to the increases in fermentative-related bacteria (Smithella and Acetobacteroides), homoacetogen (Treponema), and methanogens. The increased abundances of anaerobic functional genes further verified the mechanism of CH4 production. Furthermore, the abundances of potential hosts of antibiotic resistance genes (ARGs) were reduced under high nZVI concentration (1 g/L), contributing to ARGs attenuation. This study provides a comprehensive analysis of the mechanism in metabolic performance enhancement and ARGs attenuation during nZVI-assisted anaerobic CAP wastewater treatment.


Assuntos
Cloranfenicol , Purificação da Água , Anaerobiose , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Ferro/farmacologia
4.
Am J Transl Res ; 12(9): 5525-5537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042435

RESUMO

Pancreatic cancer is one of the most lethal cancers and its prognosis remains poor. ADAM family proteins like ADAM10, ADAM9 and ADAM17 function as α-secretase to cleavage cell surface proteins like Notch to facilitate oncogenesis in various tumors. The oncogenic roles of α-secretase in PDAC have been demonstrated but it remains unknown that whether and how α-secretase is regulated in PDAC. Here, we report that the expression of tetraspanin CD9 was increased and strongly associated with poor prognosis in PDAC. CD9 expression was positively associated with α-secretase activity in PDAC tissues and CD9 knock-down inhibited α-secretase activity in PDAC cell lines. Co-immunoprecipitation and GST pull down demonstrates that CD9 directly interacted with ADAM10, ADAM9 and ADAM17, respectively. Cell surface biotin labeling and immunostaining of tagged ADAM proteins show that CD9 promoted cell surface trafficking of ADAM family proteins. In addition, the antibody targeting extracellular domain of CD9 disrupted the interactions between CD9 and ADAM family proteins, reduced cell surface trafficking of ADAM proteins and inhibited α-secretase activity. Notch signaling was inhibited by CD9 knockdown or CD9 antibody in cell lines. Finally, CD9 antibody showed anti-tumor effects in cell proliferation MTT assay, transwell migration assay and colony formation assay. Our study reveals a novel CD9/ADAM/Notch signaling network in PDAC and it supports that targeting CD9-ADAM interaction with antibody may be a potential therapeutic intervention for PDAC.

5.
Adv Sci (Weinh) ; 7(8): 1903213, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32328423

RESUMO

Perovskite-based light-emitting diodes (PeLEDs) are now approaching the upper limits of external quantum efficiency (EQE); however, their application is currently limited by reliance on lead and by inadequate color purity. The Rec. 2020 requires Commission Internationale de l'Eclairage coordinates of (0.708, 0.292) for red emitters, but present-day perovskite devices only achieve (0.71, 0.28). Here, lead-free PeLEDs are reported with color coordinates of (0.706, 0.294)-the highest purity reported among red PeLEDs. The variation of the emission spectrum is also evaluated as a function of temperature and applied potential, finding that emission redshifts by <3 nm under low temperature and by <0.3 nm V-1 with operating voltage. The prominent oxidation pathway of Sn is identified and this is suppressed with the aid of H3PO2. This strategy prevents the oxidation of the constituent precursors, through both its moderate reducing properties and through its forming complexes with the perovskite that increase the energetic barrier toward Sn oxidation. The H3PO2 additionally seeds crystal growth during film formation, improving film quality. PeLEDs are reported with an EQE of 0.3% and a brightness of 70 cd m-2; this is the record among reported red-emitting, lead-free PeLEDs.

6.
Nano Lett ; 20(5): 3747-3753, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32242668

RESUMO

A comprehensive understanding of the ultrafast electron dynamics in two-dimensional transition metal dichalcogenides (TMDs) is necessary for their applications in optoelectronic devices. In this work, we contribute a study of ultrafast electron cooling and decay dynamics in the supported and suspended monolayer WS2 by time- and energy-resolved photoemission electron microscopy (PEEM). Electron cooling in the Q valley of the conduction band is clearly resolved in energy and time, on a time scale of 0.3 ps. Electron decay is mainly via a defect trapping process on a time scale of several picoseconds. We observed that the trap states can be produced and increased by laser illumination under an ultrahigh vacuum, and the higher local optical-field intensity led to the faster increase of trap states. The enhanced defect trapping could significantly modify the carrier dynamics and should be paid attention to in photoemission experiments for two-dimensional materials.

7.
Sci Adv ; 6(8): eaax5253, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32128394

RESUMO

According to the cohesion-tension theory, mangrove trees desalinate salty water using highly negative pressure (or tension) that is generated by evaporative capillary forces in mangrove leaves. Here, we demonstrate a synthetic mangrove that mimics the main features of the natural mangrove: capillary pumping (leaves), stable water conduction in highly metastable states (stem), and membrane desalination (root). When using nanoporous membranes as leaves, the maximum osmotic pressures of saline feeds (10 to 30 bar) allowing pure water uptake precisely correspond to expected capillary pressures based on the Young-Laplace equation. Hydrogel-based leaves allow for stable operation and desalination of hypersaline solutions with osmotic pressures approaching 400 bar, fivefold greater than the pressure limits of conventional reverse osmosis. Our findings support the applicability of the cohesion-tension theory to desalination in mangroves, provide a new platform to study plant hydraulics, and create possibilities for engineered membrane separations using large, passively generated capillary pressures.

8.
Sci Total Environ ; 722: 137660, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32179296

RESUMO

High salinity and low temperature are generally considered to have negative effects on the formation, stability and performance of aerobic granular sludge (AGS). This study investigated whether and how salinity acclimation strategies can enhance aerobic granulation at low temperature (12 °C) in three sequencing batch reactors (SBRs). Stepwise increased concentrations of NaCl (2-10 and 4-20 g/L) were added to the influent of R1 and R2 with steps of 1 and 2 g/L per week respectively, while R0 was set as a control (salt-free). The granulation processes in R1 and R2 were rapidly started up within 9 days, and were completed within 21 and 18 days, respectively. By contrast, R0 took 25 days and 49 days to start and complete granulation. The salinity acclimation strategies improved sludge hydrophobicity, reduced repulsion barrier between cells, and stimulated EPS production during granulation processes, which simultaneously promoted the formation of AGS. When the influent salinity reached 14 g/L on day 35, granule hydrophobicity, density and size in R2 sharply decreased and granules began to disintegrate afterwards. When operated under salt-free condition, sludge bulking occurred in R0 since day 60. The treatment performance was thus impaired in these two reactors, especially in R2 with significant biomass loss. Conversely, the AGS developed in R1 maintained stable structure with high biomass concentration (8.0 gSS/L) and excellent treatment performance for COD (90%), ammonium (95%) and total nitrogen (70%). Genera Thauera, Azoarcus, and Nitrosomonas were more enriched, while Flavobacterium and Meganema were more suppressed in R1, which would have contributed to granule stability and treatment performance. In conclusion, great care has to be taken for cultivating and operating AGS at low temperature for treating saline wastewater. Increasing salinity with a lower salt gradient provides a possibility for rapid granulation of AGS with excellent treatment performance under such conditions.


Assuntos
Salinidade , Aerobiose , Reatores Biológicos , Esgotos , Temperatura , Eliminação de Resíduos Líquidos
9.
Org Lett ; 21(12): 4619-4622, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31145632

RESUMO

An electrochemical oxidative difunctionalization of allyl alcohols for the synthesis of ß-trifluoromethyl ketones is achieved through a 1,2-migration process. A series of ß-trifluoromethyl ketones can be facilely obtained utilizing CF3SO2Na as a radical source, eliminating the use of metals and sacrificial chemical oxidants. Importantly, this protocol not only realizes aryl migration but also offers alkyl-migration products. Additionally, an electrochemically catalyzed ring expansion and gram-scale reaction demonstrated the synthetic usefulness of this protocol.

10.
Water Res ; 156: 199-207, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30917300

RESUMO

The anaerobic process is a favorable alternative for the treatment of antibiotic pharmaceutical wastewater. The electrically assisted anaerobic process can be used to accelerate contaminant removal, especially for persistent organic pollutants such as antibiotics. In this study, an electrically assisted anaerobic system for chloramphenicol (CAP) wastewater treatment was developed. The system performance and the underlying metabolic mechanisms were evaluated under different applied voltages. With the increase of applied voltage from 0 to 2 V, the CAP removal efficiencies increased from 53.3% to 89.7%, while the methane production increased more than three times. The microbial community structure and correlation analysis showed that electrical stimulation selected the dominant functional bacteria and increased antibiotic resistance in dominant functional bacteria, both of which enhanced CAP removal and methane production. The improved CAP removal was a result of the presence of dechlorination-related bacteria (Acidovorax, Sedimentibacter, Thauera, and Flavobacterium) and potential electroactive bacteria (Shewanella and Comamonas), both of which carried ARGs and therefore could survive the biotoxicity of CAP. The enhanced methane production could be partly attributed to the surviving fermentative-related bacteria (Paludibacter, Proteiniclasticum, and Macellibacteroides) in the anaerobic bioreactor. The increased abundances of methanogenic genes (mcrA and ACAS genes) under high voltage further confirmed the enhanced methane production of this electrically assisted anaerobic system. The fundamental understanding of the mechanisms underlying metabolic performance enhancement is critical for the further development of anaerobic wastewater treatment.


Assuntos
Cloranfenicol , Águas Residuárias , Anaerobiose , Reatores Biológicos , Metano , Eliminação de Resíduos Líquidos
11.
Environ Int ; 126: 127-133, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30797102

RESUMO

Concerns have been raised regarding co-selection for antibiotic resistance among microorganisms exposed to antibiotics and metals. As a promising approach for treating antibiotics and heavy metal-containing wastewater, a bio-electrochemical system (BES) can be used for antibiotic and heavy metal removal. This study determined the fate of antibiotic resistance genes (ARGs) in a BES when exposed to chloramphenicol (CAP) and Cu2+. The ARGs encoding the efflux pump (cmlA, floR, and tetC), the class 1 integron integrase-encoding gene, and the sul1 gene were analyzed. The results indicated that the co-existence of CAP and different concentrations of Cu2+ had significant influence on the relative abundances of the ARGs. The changes in the bacterial community structure and the results of a quantitative correlation analysis between the bacterial community and the ARGs confirmed that the shift in the potential hosts was the key reason for the changes of the ARGs. This study sheds new light on the mechanisms of ARGs variations in BES under the co-selection pressure of antibiotics and heavy metals.


Assuntos
Antibacterianos/análise , Cloranfenicol/análise , Cobre/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Poluentes Químicos da Água/análise , Bactérias/genética , Técnicas Eletroquímicas , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise
12.
Nanoscale Res Lett ; 14(1): 33, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30680579

RESUMO

In this paper, a nano-watt resistorless subthreshold voltage reference with high-power supply rejection ratio (PSRR) is presented. A self-biased MOS voltage divider is proposed to provide bias current for whole voltage reference, which is a positive temperature coefficient (TC) current containing threshold voltage characteristics. By injecting the generated current into a transistor with a different threshold voltage, a delta threshold voltage with a greatly reduced negative TC is realized and temperature-compensated by a generated positive TC item at the same time. Therefore, a temperature-stable voltage reference is achieved in the proposed compacted method with low power consumption and high PSRR. Verification results with 65-nm CMOS technology demonstrate that the minimum supply voltage can be as low as 0.35 V with a 0.00182-mm2 active area. The generated reference voltage is 148 mV, with a TC of 28 ppm/°C for the - 30 to 80 °C temperature range. The line sensitivity is 1.8 mV/V, and the PSRR without any filtering capacitor at 100 Hz is 53 dB with a 2.28-nW power consumption.

13.
Environ Sci Technol ; 52(15): 8666-8673, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29984583

RESUMO

Biological wastewater treatment is not effective in removal of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). In this study, we fabricated a photocatalytic reactive membrane by functionalizing polyvinylidene fluoride (PVDF) ultrafiltration (UF) membrane with titanium oxide (TiO2) nanoparticles for the removal of ARB and ARGs from a secondary wastewater effluent. The TiO2-modified PVDF membrane provided complete retention of ARB and effective photocatalytic degradation of ARGs and integrons. Specifically, the total removal efficiency of ARGs (i.e., plasmid-mediated floR, sul1, and sul2) with TiO2-modified PVDF membrane reached ∼98% after exposure to UV irradiation. Photocatalytic degradation of ARGs located in the genome was found to be more efficient than those located in plasmid. Excellent removal of integrons (i.e., intI1, intI2, and intI3) after UV treatment indicated that the horizontal transfer potential of ARGs was effectively controlled by the TiO2 photocatalytic reaction. We also evaluated the antifouling properties of the TiO2-UF membrane to demonstrate its potential application in wastewater treatment.


Assuntos
Antibacterianos , Águas Residuárias , Bactérias , Resistência Microbiana a Medicamentos , Genes Bacterianos , Ultrafiltração
14.
Brain Inj ; 32(11): 1405-1412, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29985665

RESUMO

OBJECTIVE: Delayed neurological deficit was often observed in patients underwent craniectomy, which could be improved by cranioplasty. Little is known about hemodynamic improvement before and after cranioplasty. METHODS: Cerebral blood perfusion, tympanic membrane temperature (TMT), neuropsychological and cognitive function were assessed in eleven craniectomy patients before and after cranioplasty. RESULTS: Before cranioplasty, the cerebral blood volume (CBV) on the decompressed side was significantly lower than that of the contralateral side. The cranioplasty led to instant improvement (7 days after cranioplasty) of cerebral perfusion at the cranioplasty side in the frontal lobe, parietal lobe, temporal lobe, mesencephalon, basal ganglia and thalamus, but not the occipital lobe and epencephalon. Interestingly, CBV of the thalamus and basal ganglia gradually decreased to pre-surgical status 6 months later while the frontal lobe, parietal lobe, temporal lobe, mesencephalon remained well perfused. Meanwhile, the TMT changes acquired positive correlation with the perfusion of temporal lobe and mesencephalon as well as the GCS and MMSE score. CONCLUSION: The cranioplasty remarkably improves neurological and cognitive function by ameliorating cerebral perfusion in certain regions. The TMT could be used as a non-invasive method to monitor the cerebral perfusion improvement after the cranioplasty.


Assuntos
Temperatura Corporal/fisiologia , Circulação Cerebrovascular/fisiologia , Craniectomia Descompressiva/métodos , Membrana Timpânica/cirurgia , Lesões Encefálicas/cirurgia , Feminino , Seguimentos , Lateralidade Funcional , Escala de Resultado de Glasgow , Humanos , Masculino , Testes Neuropsicológicos , Resultado do Tratamento , Membrana Timpânica/fisiologia
15.
Chemosphere ; 193: 840-846, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29874757

RESUMO

The presence of antibiotics in wastewater has been widely confirmed. Membrane bioreactor (MBR), as an efficient wastewater treatment technology, has attracted increasing interest in its ability to remove antibiotics in recent years. However, its long-term operation stability and the underlying mechanisms for antibiotics removal are still poorly understood. In this study, a hollow fiber MBR was used to treat low concentration sulfamethazine (SMZ) contained wastewater. The long-term effects of various SMZ concentrations on nutrients removal, SMZ degradation, and sludge characteristics were investigated. During the 244 days operation, the overall SMZ removal efficiency could reach 95.4 ± 4.5% under various SMZ concentrations and hydraulic retention times. The reactor exhibited high chemical oxygen demand and NH4+-N removal efficiencies, which reached 93.0% and 96.2%, respectively. A sludge concentration of 4.1 ± 0.3 g/L was maintained in the system without excess sludge discharge. The dosage of SMZ had obvious effect on sludge characteristics. The contents of extracellular polymeric substances (EPS) in MBR decreased after a long-term operation of the reactor under SMZ pressure. The low sludge concentration and the reduced EPS content were also beneficial for mitigating membrane fouling. Thus, this study provides a low-cost, efficient and simple approach to treat SMZ-contained wastewater.


Assuntos
Reatores Biológicos/normas , Sulfametazina/química , Águas Residuárias/química , Purificação da Água/métodos
16.
Environ Sci Technol ; 52(13): 7279-7288, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29851340

RESUMO

We demonstrate the fabrication of a loose, negatively charged nanofiltration (NF) membrane with tailored selectivity for the removal of perfluoroalkyl substances with reduced scaling potential. A selective polyamide layer was fabricated on top of a poly(ether sulfone) support via interfacial polymerization of trimesoyl chloride and a mixture of piperazine and bipiperidine. Incorporating high molecular weight bipiperidine during the interfacial polymerization enables the formation of a loose, nanoporous selective layer structure. The fabricated NF membrane possessed a negative surface charge and had a pore diameter of ∼1.2 nm, much larger than a widely used commercial NF membrane (i.e., NF270 with pore diameter of ∼0.8 nm). We evaluated the performance of the fabricated NF membrane for the rejection of different salts (i.e., NaCl, CaCl2, and Na2SO4) and perfluorooctanoic acid (PFOA). The fabricated NF membrane exhibited a high retention of PFOA (∼90%) while allowing high passage of scale-forming cations (i.e., calcium). We further performed gypsum scaling experiments to demonstrate lower scaling potential of the fabricated loose porous NF membrane compared to NF membranes having a dense selective layer under solution conditions simulating high water recovery. Our results demonstrate that properly designed NF membranes are a critical component of a high recovery NF system, which provide an efficient and sustainable solution for remediation of groundwater contaminated with perfluoroalkyl substances.


Assuntos
Fluorcarbonetos , Membranas Artificiais , Nylons , Polimerização , Água
17.
J Environ Sci (China) ; 67: 154-160, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29778148

RESUMO

Inexact mechanism of aerobic granulation still impedes optimization and application of aerobic granules. In this study, the extended Derjaguin, Landau, Verwey, and Overbeek (XDLVO) theory and physicochemical properties were combined to assess the aggregation ability of sludge during aerobic granulation process qualitatively and quantitatively. Results show that relative hydrophobicity of sludge and polysaccharide content of extracellular polymeric substances (EPS) increased, while electronegativity of sludge decreased during acclimation phase. After 20days' acclimation, small granules began to form due to high aggregation ability of sludge. Since then, coexisted flocs and granules possessed distinct physicochemical properties during granulation and maturation phase. The relative hydrophobicity decreased while electronegativity increased for flocs, whereas that for granules presented reverse trend. Through analyzing the interaction energy using the XDLVO theory, small granules tended to self-grow rather than self-aggregate or attach of flocs due to poor aggregation ability between flocs and granules during the granulation phase. Besides, remaining flocs were unlikely to self-aggregate owing to poor aggregation ability, low hydrophobicity and high electronegativity.


Assuntos
Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Reatores Biológicos , Floculação , Polímeros/química , Polissacarídeos/química
18.
Bioresour Technol ; 260: 61-67, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29614452

RESUMO

Recovery of volatile fatty acids (VFAs) from wastewater is an important route for wastewater valorization. Selective acidogenic fermentation enables an efficient production of VFAs from wastewater, whereas electrodialysis (ED) provides an effective approach to concentrate VFAs. However, these two processes have not been coupled in one single system previously. In this study, an acidogenesis-ED integrated system that coupled a continuous acidogenesis with a batch process of VFA concentration was developed for recovery of high-concentration VFAs from wastewater. Under 20.0 V voltage, the acetate was concentrated by 4-fold and the propionate and butyrate were concentrated by over 3-fold in the integrated system after 528-h operation. The declined VFAs recovery ratios at the later stage due to significant reverse diffusion indicate a need to prevent product over-accumulation. This work demonstrated the feasibility of the acidogenesis-ED integrated reactor for wastewater valorization and discussed the remaining challenges and opportunities.


Assuntos
Ácidos Graxos Voláteis , Águas Residuárias , Reatores Biológicos , Ácido Butírico , Fermentação , Concentração de Íons de Hidrogênio , Propionatos , Esgotos
19.
Water Res ; 133: 79-86, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29367050

RESUMO

Pharmaceutical wastewaters containing antibiotics and high salinity can damage traditional biological treatment and result in the proliferation of antibiotic resistance genes (ARGs). Bioelectrochemical system (BES) is a promising approach for treating pharmaceutical wastewater. However, the fate of ARGs in BES and their correlations with microbial communities and horizontal genes transfer are unknown. In this study, we investigated the response of ARGs to bio-electrochemical treatment of chloramphenicol wastewater and their potential hosts under different salinities. Three ARGs encoding efflux pump (cmlA, floR and tetC), one class 1 integron integrase encoding gene (intI1), and sul1 gene (associate with intI1) were analyzed. Correlation analysis between microbial community and ARGs revealed that the abundances of potential hosts of ARGs were strongly affected by salinity, which further determined the alteration in ARGs abundances under different salinities. There were no significant correlations between ARGs and intI1, indicating that horizontal gene transfer was not related to the important changes in ARGs. Moreover, the chloramphenicol removal efficiency was enhanced under a moderate salinity, attributed to the altered microbial community driven by salinity. Therefore, microbial community shift is the major factor for the changes of ARGs and chloramphenicol removal efficiency in BES under different salinities. This study provides new insights on the mechanisms underlying the alteration of ARGs in BES treating high-salinity pharmaceutical wastewater.


Assuntos
Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Eliminação de Resíduos Líquidos/métodos , Antibacterianos/química , Cloranfenicol/química , Técnicas Eletroquímicas , Salinidade , Águas Residuárias/análise , Poluentes Químicos da Água/química
20.
Bioresour Technol ; 247: 471-476, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28968568

RESUMO

In this study, a novel electrodialysis membrane bioreactor was used for EBPR sludge treatment for energy and phosphorus resource recovery simultaneously. After 30days stable voltage outputting, the maximum power density reached 0.32W/m3. Over 90% of phosphorus in EBPR sludge was released while about 50% of phosphorus was concentrated to 4mmol/L as relatively pure phosphate solution. Nitrogen could be removed from EBPR sludge by desalination and denitrification processes. This study provides an optimized way treating sludge for energy production and in situ phosphorus recovery.


Assuntos
Reatores Biológicos , Esgotos , Eletricidade , Nitrogênio , Fosfatos , Fósforo
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