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Two Gram-stain-negative, motile, facultatively anaerobic, rod-shaped strains, FJAT-53720T and FJAT-53726, were isolated from rhizosphere sediment of plant Cyperus malaccensis. Phylogenetic analysis based on their 16S rRNA gene sequences revealed that strains FJAT-53720T and FJAT-53726 were affiliated to the genus Shewanella (forming an independent cluster) with the highest sequence similarity to the type strain of Shewanella algae. Optimum growth of both strains was observed at 30 °C and pH 7. The respiratory quinones were Q-7, Q-8 and MK-7. The polar lipid profile included phosphatidylmethyl ethanolamine, phosphatidylethanolamine, diphosphatidylglycerol, one unidentified aminophospholipid and four unknown phospholipids. The major fatty acids of strains FJAT-53720T and FJAT-53726 were iso-C15:0, C17â:â1 ω8c and summed feature 3. The genomic DNA G+C content of strain FJAT-53720T was 55.6 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between FJAT-53720T and FJAT-53726 were 97.4 and 77.9â%, confirming that they were similar species and hence FJAT-53720T was selected for further analysis. The ANI and dDDH values between FJAT-53720T and other members of the genus Shewanella were below the cut-off level (95-96â%; 70â%) for species delineation. Based on the above results, FJAT-53720T represents a novel species of the genus Shewanella, for which the name Shewanella cyperi sp. nov. is proposed. The type strain is FJAT-53720T (=KCTC 82444T=GDMCC 1.2207T).
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Sedimentos Geológicos/microbiología , Filogenia , Rizosfera , Shewanella , Anaerobiosis , Técnicas de Tipificación Bacteriana , Composición de Base , China , Cyperus/microbiología , ADN Bacteriano/genética , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Shewanella/clasificación , Shewanella/aislamiento & purificación , Vitamina K 2/química , HumedalesRESUMEN
Use of tight ultrafiltration (UF) membranes has created a new pathway in fractionation of dye/salt mixtures from textile wastewater for sustainable resource recovery. Unexpectedly, a consistently high rejection for the dyes with smaller sizes related to the pore sizes of tight UF membranes is yielded. The potential mechanism involved in this puzzle remains unclear. In this study, seven tailored UF membranes with molecular weight cut-offs (MWCOs) from 6050 to 17530 Da were applied to separate dye/salt mixtures. These UF membranes allowed a complete transfer for NaCl and Na2SO4, due to large pore sizes. Additionally, these UF membranes had acceptably high rejections for direct and reactive dyes, due to the aggregation of dyes as clusters for enhanced sizes and low diffusivity. Specifically, the membrane with an MWCO of 7310 Da showed a complete rejection for reactive blue 2 and direct dyes. An integrated UF-diafiltration process was subsequently designed for fractionation of reactive blue 2/Na2SO4 mixture, achieving 99.84% desalination efficiency and 97.47% dye recovery. Furthermore, reactive blue 2 can be concentrated from 2.01 to 31.80 g·L-1. These results indicate that UF membranes even with porous structures are promising for effective fractionation of dyes and salts in sustainable textile wastewater treatment.
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Aguas Residuales , Purificación del Agua , Colorantes , Membranas Artificiales , Cloruro de Sodio , Textiles , UltrafiltraciónRESUMEN
Under the environmental sustainability concept, landfill leachate concentrate can be up-cycled as a useful resource. Practical strategy for effective management of landfill leachate concentrate is to recover the existing humate as fertilizer purpose for plant growth. Herein, we designed an electro-neutral nanofiltration membrane to separate the humate and inorganic salts for achieving a sufficient humate recovery from leachate concentrate. The electro-neutral nanofiltration membrane yielded a high retention of humate (96.54 %) with an extremely low salt rejection (3.47 %), tremendously outperforming the state-of-the-art nanofiltration membranes and exhibiting superior promise in fractionation of humate and inorganic salts. With implementation of the pressure-driven concentration process, the electro-neutral nanofiltration membrane enriched the humate from 1756 to 51,466 mgâL-1 at a fold of 32.6, enabling 90.0 % humate recovery and 96.4 % desalination efficiency from landfill leachate concentrate. Furthermore, the recovered humate not only exerted no phytotoxicity, but also significantly promoted the metabolism of red bean plants, serving as an effective green fertilizer. The study provides a conceptual and technical platform using high-performance electro-neutral nanofiltration membranes to extract the humate as a promising nutrient for fertilizer application, in view of sustainable landfill leachate concentrate treatment.
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Waste management has become an ever-increasing global issue due to population growth and rapid globalisation. For similar reasons, the greenhouse effect caused by fossil fuel combustion, is leading to chronic climate change issues. A novel approach, the waste-to-hydrogen process, is introduced to address the concern of waste generation and climate change with an additional merit of production of a renewable, higher energy density than fossil fuels and sustainable transportation fuel, hydrogen (H2) gas. In the downstream H2 purifying process, membrane separation is one of the appealing options for the waste-to-hydrogen process given its low energy consumption and low operational cost. However, commercial polymeric membranes have hindered membrane separation process due to their low separation performance. By introducing novel two-dimensional materials as substitutes, the limitation of purifying using conventional membranes can potentially be solved. Herein, this article provides a comprehensive review of two-dimensional materials as alternatives to membrane technology for the gas separation of H2 in waste-to-hydrogen downstream process. Moreover, this review article elaborates and provides some perspectives on the challenges and future potential of the waste-to-hydrogen process and the use of two-dimensional materials in membrane technology.
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Hidrógeno , Administración de Residuos , Hidrógeno/análisis , Administración de Residuos/métodos , Combustibles FósilesRESUMEN
BACKGROUND: We aim to investigate the prognostic factors and evaluate the role of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) in local advanced rectal cancer (LARC) patients who received neoadjuvant chemoradiotherapy (neo-CRT), radical surgery and postoperative chemotherapy. METHODS: In total, 197 cases of LARC patients who underwent neo-CRT, total mesorectal excision (TME), and adjuvant chemotherapy were recruited. Serum levels of CEA and CA19-9 were detected both at baseline and after neo-chemoradiotherapy. Multivariate analysis was used to assess correlations between levels of CEA and CA19-9 and patients' prognosis (survival, recurrence, and metastasis). Rates of survival, distant metastasis (DM), and local recurrence (LR) were estimated using Kaplan-Meier survival analysis, the log-rank test, and Cox proportional hazards. RESULTS: The median follow-up time was 45.3 months, and a cohort of 197 patients was analyzed; 84 (42.6%) patients had elevated baseline CEA levels, 21 (10.7%) patients had elevated baseline CA19-9 levels, and 14 (7.1%) patients had both; 77.4% (65/84) patients with high CEA levels and 76.2% (16/21) with high CA19-9 levels returned to normal after neo-chemoradiotherapy. The Cox regression model suggested that elevated CEA was associated with an increased risk of disease-free survival (DFS) (HR: 2.058, 95% CI: 1.034-4.096, P=0.040) and DM (HR: 2.144, 95% CI: 1.058-4.346, P=0.034). Elevated CA19-9 was identified as an independent prognostic factor, with poorer overall survival (OS) (HR: 2.894, 95% CI: 1.196-7.006, P=0.018) and DFS (HR: 4.533, 95% CI: 2.067-9.940, P<0.001) and increased incidences of LR (HR: 6.139, 95% CI: 1.813-20.783, P=0.004) and DM (HR: 4.052, 95% CI: 1.892-8.678, P<0.001). Besides, combined CEA with CA19-9 was a stronger prognostic predictor. Patients with both high levels of CEA and CA19-9 had the poorest DFS (HR: 8.157, 95% CI: 3.232-20.591, P<0.001) and the highest risk of DM (HR: 8.790, 95% CI: 3.324-23.248, P<0.001). CONCLUSIONS: LARC patients with high levels of CEA or/and CA19-9 at initial treatment have a worse prognosis, even after neo-CRT, subsequent radical resection, and adjuvant chemotherapy. These findings suggest that this subset of patients requires more intensive treatment or additional treatment strategies.
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Sustainable treatment of the highly saline landfill leachate concentrate for application as green fertilizer calls for effective fractionation of the existing humic substances and inorganic salts; advanced selective nanofiltration membranes are proposed for this. One-step, rapid assembly of a tannic acid-Fe3+ coordination complex is a promising strategy to endow the membranes with an enhanced nanofiltration performance. In this study, a robust and homogeneous tannic acid-Fe3+ coordination complex layer was effectively coated onto the surface of a loose nanofiltration substrate in an extremely short time (15 s). After the coating of the tannic acid-Fe3+ coordination complex layer, the nanofiltration membrane showed a significantly reduced molecule weight cutoff (i.e., reduction from 601 to 279 Da) and thus enhanced selectivity towards humic substances. Specifically, the rejection to humic substances of the coated nanofiltration membrane increased from 95.31±0.54% to 99.32±0.18% with negligible rise in salt rejection, demonstrating an enhanced fractionation efficacy for humic substances and salts. Assisted by a diafiltration operation with the coated nanofiltration membrane, humic substances in the landfill leachate concentrate were effectively purified and extracted with 96.60% recovery. Particularly, the humic substances were linearly enriched by ca. 7.8 folds (i.e., from 1837 to 13970 mg·L-1) with a purity of 98.91% for potential application as liquid fertilizer. The one-step rapid tannic acid-Fe3+ coordination complex coating exhibits an impressive efficacy to engineer advanced nanofiltration membranes that could be applied at a large scale for sustainable resource extraction from landfill leachate concentrate.
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Complejos de Coordinación , Contaminantes Químicos del Agua , Fraccionamiento Químico , Sustancias Húmicas , MetalesRESUMEN
Nitrous oxide (N2O) emission is an environmental problem related to composting. Recently, the electric field-assisted aerobic composting process has been found to be effective for enhancing compost maturity and mitigating N2O emission. However, the insertion of electrodes into the compost pile causes electrode erosion and inconvenience in practical operation. In this study, a novel alternating magnetic field-assisted aerobic composting (AMFAC) process was tested by applying an alternating magnetic field (AMF) to a conventional aerobic composting (CAC) process. The total N2O emission of the AMFAC process was reduced by 39.8% as compared with that of the CAC process. Furthermore, the results demonstrate that the AMF weakened the expressions of the amoA, narG, and nirS functional genes (the maximum reductions were 96%, 83.7%, and 95.5%, respectively), whereas it enhanced the expression of the nosZ functional gene by a maximum factor of 36.5 as compared with that in CAC. A correlation analysis revealed that the nitrification and denitrification processes for N2O emission were suppressed in AMFAC, the main source of N2O emission of which was denitrification. The findings imply that AMFAC is an effective strategy for the reduction of N2O emission during aerobic composting.
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Compostaje , Animales , Pollos , Desnitrificación , Campos Magnéticos , Estiércol , Nitrificación , Óxido NitrosoRESUMEN
Effective extraction of useful resources from high-salinity textile wastewater is a critical pathway for sustainable wastewater management. In this study, an integrated loose nanofiltration-electrodialysis process was explored for simultaneous recovery of dyes, NaCl and pure water from high-salinity textile wastewater, thus closing the material loop and minimizing waste emission. Specifically, a loose nanofiltration membrane (molecular weight cutoff of ~800 Da) was proposed to fractionate the dye and NaCl in the high-salinity textile wastewater. Through a nanofiltration-diafiltration unit, including a pre-concentration stage and a constant-volume diafiltration stage, the dye could be recovered from the high-salinity textile wastewater, being enriched at a factor of ~9.0, i.e., from 2.01 to 17.9 g·L-1 with 98.4% purity. Assisted with the subsequent implementation of electrodialysis, the NaCl concentrate and pure water were effectively reclaimed from the salt-containing permeate coming from the loose nanofiltration-diafiltration. Simultaneously, the produced pure water was further recycled to the nanofiltration-diafiltration unit. This study shows the potential of the integration of loose nanofiltation-diafiltration with electrodialysis for sufficient resource extraction from high-salinity textile wastewater.
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Aguas Residuales , Purificación del Agua , Membranas Artificiales , Salinidad , TextilesRESUMEN
BACKGROUND: Neoadjuvant chemoradiation therapy is part of the standard treatment of locally advanced rectal cancer (LARC). Although various options for modifying preoperative radiotherapy protocols have been researched and proposed, there is still no consensus as to the most appropriate dose regimen of neoadjuvant therapy for this disease. AIM: To evaluate the effects of relatively low-dose radiation regimens on tumor regression and clinical outcomes in rectal cancer patients treated with neoadjuvant CRT followed by mesorectal excision. METHODS AND RESULTS: We retrospectively analyzed patients with LARC who underwent neoadjuvant concurrent chemoradiation (CCRT) in our hospital from June 2010 to December 2015. A total of 259 consecutive patients were enrolled, receiving 42 to 44 Gy (RLD, n = 31), 46 Gy (SD1, n = 69), or 50 Gy (SD2, n = 159) of CRT, combined with either capecitabine/oxaliplatin or capecitabine only or mFOLFOX6, followed by total mesorectal excision. A 1:4 propensity score matching was employed, and all patients in the RLD group were matched with 124 patients in the SD2 group. Rates of pCR, 3-year local/regional recurrence (LRR), overall survival (OS), and disease-free survival (DFS) in the RLD group were all not significantly different (0.313 for pCR; 0.884 for LRR; and 0.762 for OS; 0.101 for DFS) from those in SD1 and SD2 groups. The RLD group showed a lower incidence of grade 3 to 4 hematologic toxicity than SD2 group (0.019). A propensity score analysis demonstrated no significant differences in the pCR rates and 3-year outcomes between the RLD and SD2 group. CONCLUSION: Relatively low-dose regimen (≤44 Gy) of neoadjuvant CRT combined with standard concurrent chemotherapy appears to be both safe and effective in Chinese patients with LARC. Further testing by prospective randomized trials is needed.
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Quimioradioterapia Adyuvante/métodos , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/epidemiología , Traumatismos por Radiación/epidemiología , Neoplasias del Recto/terapia , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Quimioradioterapia Adyuvante/efectos adversos , Supervivencia sin Enfermedad , Relación Dosis-Respuesta en la Radiación , Estudios de Factibilidad , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/efectos adversos , Recurrencia Local de Neoplasia/prevención & control , Compuestos Organoplatinos/administración & dosificación , Proctectomía , Puntaje de Propensión , Traumatismos por Radiación/etiología , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Recto/efectos de los fármacos , Recto/patología , Recto/efectos de la radiación , Recto/cirugía , Estudios RetrospectivosRESUMEN
Developing a highly efficient, cost-effective, easily scalable and sustainable cathode for oxygen reduction reaction (ORR) is a crucial challenge in terms of future "green" energy conversion technologies, e.g., microbial fuel cells (MFCs). In this study, a natural and widely available lotus leaf with intrinsically hierarchical structure was employed to serve as the single precursor to prepare the catalyst applied as the MFC cathode. The hierarchically particle-coated biocarbon was self-constructed from the lotus leaf, which yielded a large specific surface area, highly porous structure and superhydrophobicity via facile pyrolysis coupling hydrothermal activation by ZnCl2/(NH4)2SO4. Electrochemical evaluation demonstrated that these natural leaf-derived carbons have an efficient ORR activity. Specifically, the HC-900 catalyst with hydrothermal activation achieved an onset potential of -0.015â¯V vs. Ag/AgCl, which was comparable to the commercial Pt/C catalyst (-0.010â¯V vs. Ag/AgCl) and was more efficient than the DC-900 catalyst through direct pyrolysis. Furthermore, the HC-900 catalyst achieved an outstanding ORR activity via a one-step and four-electron pathway, exhibiting a potential alternative to Pt/C as electrocatalyst in ORR, due to its better long-term durability and methanol resistance. Additionally, the HC-900 catalyst was applied as an effective electrocatalytic cathode in an MFC system with a maximum power density of 511.5⯱â¯25.6â¯mWâ m-2, exhibiting a superior energy harvesting capacity to the Pt/C cathode.
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Fuentes de Energía Bioeléctrica , Carbono/química , Nanoestructuras/química , Nelumbo/química , Catálisis , Técnicas Electroquímicas , Hojas de la Planta/químicaRESUMEN
The hybrid membrane bioreactor - nanofiltration treatment process can be an effective approach for treating the landfill leachate, but the residual leachate concentrate highly loaded with the humic substance and salts remains an environmental concern. Herein, a loose nanofiltration membrane (molecular weight cut-off of 860â¯Da) was used to recover the humic substance, which can act as a key component of organic fertilizer, from the leachate concentrate. The loose nanofiltration membrane showed the high permeation fluxes and high transmissions (>94.7%) for most inorganic ions (i.e., Na+, K+, Cl-, and NO3-), while retaining 95.7⯱â¯0.3% of the humic substance, demonstrating its great potential in effective fractionation of humic substance from inorganic salts in the leachate concentrate. The operation conditions, i.e., cross-flow rates and temperatures, had more pronounced impacts on the filtration performance of the loose nanofiltration membrane. Increasing cross-flow rates from 60 to 260â¯Lâ¯h-1 resulted in an improvement of ca. 7.3% in the humic substance rejection, mainly due to the reduced concentration polarization effect. In contrast, the solute rejection of the nanofiltration membrane was negatively dependent on the temperature. The rejection of humic substance decreased from 96.3⯱â¯0.3% to 92.0⯱â¯0.4% with increasing the temperature from 23 to 35⯰C, likely due to the enlargement of the membrane pore size and enhancement in solute diffusivity. The humic substance was enriched from 1735 to 15,287â¯mgâ¯L-1, yielding a 91.2% recovery ratio with 85.7% desalination efficiency at a concentration factor of 9.6. The recovered HS had significantly stimulated the seed germination and growth of the green mungbean plants with no obvious phytotoxicity. These results demonstrate that loose nanofiltration can be an effective promising technology to recover the humic substance as a valuable fertilizer component towards sustainable management of the landfill leachate concentrate.
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Contaminantes Químicos del Agua , Reactores Biológicos , Fertilizantes , Filtración , Sustancias HúmicasRESUMEN
Limited information is available on the bioaccessible fraction of trace metals in the resuspended fraction of settled bus dust in order to estimate bus drivers' occupational exposure. In this study, 45 resuspended fraction of settled dust samples were collected from gasoline and compressed natural gas (CNG) powered buses and analyzed for trace metals and their fraction concentrations using a three-step sequential extraction procedure. Experimental results showed that zinc (Zn) had the greatest bioaccessible fraction, recorded as an average of 608.53 mg/kg, followed in order of decreasing concentration by 129.80 mg/kg lead (Pb), 56.77 mg/kg copper (Cu), 34.03 mg/kg chromium (Cr), 22.05 mg/kg nickel (Ni), 13.17 mg/kg arsenic (As) and 2.77 mg/kg cadmium (Cd). Among the three settled bus dust exposure pathways, ingestion was the main route. Total exposure hazard index (HIt) for non-carcinogenic effect trace metals was lower than the safety level of 1. The incremental lifetime cancer risk (ILCR) for drivers was estimated for trace metal exposure. Pb and Ni presented relatively high potential risks in the non-carcinogenic and potentially carcinogenic health assessment for all drivers. ILCR was in the range of 1.84E-05 to 7.37E-05 and 1.74E-05 to 6.95E-05 for gasoline and CNG buses, respectively.
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Automóviles/estadística & datos numéricos , Polvo/análisis , Monitoreo del Ambiente , Metales/análisis , Exposición Profesional/estadística & datos numéricos , Ciudades/estadística & datos numéricos , HumanosRESUMEN
The application of nanoparticles as additives in membrane synthesis for improving the resistance of membranes against fouling has triggered recent interest in new membrane types. However, most nanoparticle-enhanced membranes suffer from the tradeoff between permeability and selectivity. In this paper, nano-WS2 was explored as the additive in membrane synthesis by non-solvent induced phase separation (NIPS). Blended PES-WS2 flat-sheet membranes with the incorporation of ultra-low concentrations of nanoparticles (from 0.025% to 0.25%, WS2/PES ratio) were manufactured and investigated in terms of permeability, fouling resistance and solute rejection. Remarkably, a significant enhancement in the permeability was observed as a result of the incorporation of ultra-low fractions of nano-WS2 to the membrane structure. The optimum permeability values were obtained for modified membranes with 0.075-0.10% nanoparticle/polymer concentration ratios. In general, fouling resistance and solute rejection were significantly enhanced by the incorporation of nanoparticles into the membrane structure. Specifically, fouling resistance increased by around 50%.
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Incrustaciones Biológicas/prevención & control , Membranas Artificiales , Nanopartículas del Metal , Permeabilidad , Polímeros , Sulfuros/química , Sulfonas , Compuestos de Tungsteno/química , Porosidad , Compuestos de Tungsteno/farmacología , Purificación del Agua/instrumentaciónRESUMEN
Alkaline glyphosate neutralization liquors containing a high salinity pose a severe environmental pollution problem by the pesticide industry. However, there is a high potential for glyphosate recovery due to the high concentration of glyphosate in the neutralization liquors. In the study, a three-compartment bipolar membrane electrodialysis (BMED) process was applied on pilot scale for the recovery of glyphosate and the production of base/acid with high concentration in view of zero discharge of wastewater. The experimental results demonstrate that BMED can remove 99.0% of NaCl from the feed solution and transform this fraction into HCl and NaOH with high concentration and purity. This is recycled for the hydrolysis reaction of the intermediate product generated by the means of the Mannich reaction of paraformaldehyde, glycine and dimethylphosphite catalyzed by triethylamine in the presence of HCl and reclamation of the triethylamine catalyst during the production process of glyphosate. The recovery of glyphosate in the feed solution was over 96%, which is acceptable for industrial production. The current efficiency for producing NaOH with a concentration of 2.0 mol L(-1) is above 67% and the corresponding energy consumption is 2.97 kWh kg(-1) at a current density of 60 mA cm(-2). The current efficiency increases and energy consumption decreases as the current density decreases, to 87.13% and 2.37 kWh kg(-1), respectively, at a current density of 30 mA cm(-2). Thus, BMED has a high potential for desalination of glyphosate neutralization liquor and glyphosate recovery, aiming at zero discharge and resource recycling in industrial application.