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1.
Membranes (Basel) ; 13(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37999354

RESUMO

The removal of three emerging pollutants: carbamazepine, ketoprofen, and bisphenol A, has been studied using the nanofiltration flat sheet membrane NF99HF. The removal efficiencies of the membrane have been evaluated by two system characteristic parameters: permeate flux and rejection coefficient. The influence of two operating variables has been analysed: operating pressure and feed concentration. Before and after the tests with emerging pollutants, the membrane has been characterized by determining its water permeability coefficient and its magnesium chloride rejection coefficient to find out if the removal of emerging pollutants causes membrane fouling. The results show that operating pressure has significant separation effects, obtaining the highest efficiencies at a pressure of 20 bar for pollutant concentrations between 5 and 25 mg/L. Moreover, rejection of ketoprofen was found to be dependent on electrostatic repulsion, while rejection of bisphenol A was significantly affected by adsorption onto the membrane. Finally, the experimental data have been fitted to the solution diffusion model and to the simplified model of Spiegler-Kedem-Katchalsky to predict the behaviour of the nanofiltration membrane in the removal of the tested pollutants. Good agreement between the experimental and predicted carbamazepine and bisphenol A data has been obtained with each model, respectively.

2.
Membranes (Basel) ; 12(6)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35736268

RESUMO

The presence of pharmaceutical products, and their metabolites, in wastewater has become a focus of growing environmental concern. Among these pharmaceutical products, ibuprofen (IBU) is one of the most consumed non-steroidal anti-inflammatory drugs and it can enter the environment though both human and animal consumption, because it is not entirely absorbed by the body, and the pharmaceutical industry wastewater. Nanofiltration has been described as an attractive process for the treatment of wastewater containing pharmaceutical products. In this paper, the modification of a polysulfone nanofiltration membrane by coating with graphene oxide (GO) and reduced graphene oxide (RGO) has been carried out. The morphology and elemental composition of the active layer of unmodified and modified membranes were analyzed by scanning electronic microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively. Initial characterization membranes was carried out, studying their water permeability coefficient and their permeate flux and rejection coefficients, at different applied pressures, using magnesium chloride solutions. The behavior of both pristine and coated membranes against ibuprofen solutions were analyzed by studying the permeate fluxes and the rejection coefficients at different pressures and at different contaminant concentrations. The results have shown that both GO and RGO coated membranes lead to higher values of ibuprofene rejection than that of uncoated membrane, the latter being the one that presents better results in the studies of permeability, selectivity, and fouling.

3.
J Environ Manage ; 279: 111810, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33341726

RESUMO

Olive Mill Wastewater (OMW) is a polluting residue from the olive oil industry. It is usually stored in open-air unprotected evaporation ponds where their sediments accumulate. This study compares the characteristics of OMW sludges stored for long-time in evaporation ponds and assesses their impact on the underlying soil layer. Physicochemical parameters, toxicity bioassays, and full characterization of the microbial community were analyzed. The extension of the polluting effects was assessed by analysis of toxicity, microbial biomass carbon, and respiration. Geostatistics was used to predict their spatial distribution. Organic matter and polyphenol content besides toxicity levels determine variations between OMW sludges and have a high impact on the microbiota they contain. The microbial community was abundant, diverse, and functionally active. However, the biodegradability of the sludges was hindered by the toxicity levels. Toxicity and biomass carbon were higher on the surface of the ponds than in the soil layer revealing a reduced leach flow and depletion of contaminants. The natural microbiota might be biostimulated by means of applying sustainable and feasible biological treatments in order to favor the OMW sludges bioremediation. These results open up the possibility of solving the environmental concern caused by its storage in similar scenarios, which are common in olive oil-producing countries.


Assuntos
Microbiota , Olea , Biodegradação Ambiental , Resíduos Industriais/análise , Azeite de Oliva , Lagoas , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
4.
Arch. argent. pediatr ; 114(6): e417-e420, dic. 2016. ilus
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-838307

RESUMO

El síndrome de Axenfeld-Rieger es una enfermedad congénita con una prevalencia estimada de 1 cada 200 000 individuos. La afectación oftálmica con la disgenesia del segmento anterior es la que define la enfermedad. Se puede presentar desde el período neonatal. Se asocia con afectaciones extraoculares, como dismorfismo craneal y anomalías maxilofaciales o dentarias; otras manifestaciones menos frecuentes son las cardiológicas o hipofisarias. La aparición de cardiopatia no congénita en el síndrome de Axenfeld-Rieger ha sido descrita en muy pocos casos en la literatura. Presentamos un paciente de 7 años de edad que presentó síndrome de Axenfeld-Rieger, con insuficiencia mitral ligera desde los 3 años que progresó a insuficiencia mitral moderada en la actualidad. El seguimiento cardiológico estaría indicado en pacientes con síndrome de Axenfeld-Rieger.


Axenfeld-Rieger syndrome is a congenital disease with an estimated prevalence of one in 200,000 individuals. This is an ophthalmic disorder related to anterior segment dysgenesis, which may be present from the neonatal period. It is associated with extraocular affectations such as cranial dimorphism, maxillofacial or dental anomalies. Cardiological or pituitary manifestations are less common. The congenital heart disease in Axenfeld-Rieger syndrome has been described in very few cases in the literature. We report a 7-year-old patient with Axenfeld-Rieger syndrome and mild mitral insufficiency since the age of 3 years, which is progressing to moderate mitral regurgitation at the present time. The cardiologic follow up may be indicated in patients with Axenfeld-Rieger syndrome.


Assuntos
Humanos , Masculino , Criança , Anormalidades do Olho/complicações , Segmento Anterior do Olho/anormalidades , Insuficiência da Valva Mitral/etiologia , Índice de Gravidade de Doença , Oftalmopatias Hereditárias , Seguimentos , Progressão da Doença
5.
Arch Argent Pediatr ; 114(6): e417-e420, 2016 Dec 01.
Artigo em Espanhol | MEDLINE | ID: mdl-27869423

RESUMO

Axenfeld-Rieger syndrome is a congenital disease with an estimated prevalence of one in 200,000 individuals. This is an ophthalmic disorder related to anterior segment dysgenesis, which may be present from the neonatal period. It is associated with extraocular affectations such as cranial dimorphism, maxillofacial or dental anomalies. Cardiological or pituitary manifestations are less common. The congenital heart disease in Axenfeld-Rieger syndrome has been described in very few cases in the literature. We report a 7-year-old patient with Axenfeld-Rieger syndrome and mild mitral insufficiency since the age of 3 years, which is progressing to moderate mitral regurgitation at the present time. The cardiologic follow up may be indicated in patients with Axenfeld-Rieger syndrome.


El síndrome de Axenfeld-Rieger es una enfermedad congénita con una prevalencia estimada de 1 cada 200 000 individuos. La afectación oftálmica con la disgenesia del segmento anterior es la que define la enfermedad. Se puede presentar desde el período neonatal. Se asocia con afectaciones extraoculares, como dismorfismo craneal y anomalías maxilofaciales o dentarias; otras manifestaciones menos frecuentes son las cardiológicas o hipofisarias. La aparición de cardiopatia no congénita en el síndrome de Axenfeld-Rieger ha sido descrita en muy pocos casos en la literatura. Presentamos un paciente de 7 años de edad que presentó síndrome de Axenfeld-Rieger, con insuficiencia mitral ligera desde los 3 años que progresó a insuficiencia mitral moderada en la actualidad. El seguimiento cardiológico estaría indicado en pacientes con síndrome de Axenfeld-Rieger.


Assuntos
Segmento Anterior do Olho/anormalidades , Anormalidades do Olho/complicações , Insuficiência da Valva Mitral/etiologia , Criança , Progressão da Doença , Oftalmopatias Hereditárias , Seguimentos , Humanos , Masculino , Índice de Gravidade de Doença
6.
J Sci Food Agric ; 94(11): 2308-16, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24403129

RESUMO

BACKGROUND: Different strategies for the solvent-free enzymatic production of polyglycerol polyricinoleate (PGPR) were explored in an attempt to simplify and improve the process. Besides the conventional procedure (obtaining polyricinoleic acid, followed by its esterification with polyglycerol), two alternative methods are proposed: (1) reversing the synthesis order, i.e. esterification of polyglycerol with ricinoleic acid and then the condensation of ricinoleic acid with the previously obtained polyglycerol ester; and (2) the enzymatic synthesis of PGPR in a single-step process. RESULTS: The reaction sequences were carried out in an open-air reactor with free and immobilised lipases (triacylglycerol acylhydrolases, E.C. 3.1.1.3): Candida rugosa lipase to obtain polyricinoleic acid and Rhizopus oryzae lipase for the esterification of polyglycerol with the carboxyl group of ricinoleic or polyricinoleic acid. A co-immobilised derivative containing both lipases was used to catalyse the single-stage scheme. The three processes were carried out in a vacuum reactor, obtaining in every case PGPR that complied with the legal specifications of the European Community and recommendations provided in the Food Chemical Codex. CONCLUSION: The results demonstrate that all three protocols are viable for the enzymatic synthesis of PGPR and require similar reaction times. The single-stage scheme is easier to carry out.


Assuntos
Candida/enzimologia , Enzimas Imobilizadas/metabolismo , Glicerol/análogos & derivados , Lipase/metabolismo , Polímeros/metabolismo , Rhizopus/enzimologia , Ácidos Ricinoleicos/metabolismo , Biocatálise , Esterificação , Ésteres , Glicerol/metabolismo
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