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BACKGROUND: Staphylococcus shinii appears as an umbrella species encompassing several strains of Staphylococcus pseudoxylosus and Staphylococcus xylosus. Given its phylogenetic closeness to S. xylosus, S. shinii can be found in similar ecological niches, including the microbiota of fermented meats where the species may contribute to colour and flavour development. In addition to these conventional functionalities, a biopreservation potential based on the production of antagonistic compounds may be available. Such potential, however, remains largely unexplored in contrast to the large body of research that is available on the biopreservative properties of lactic acid bacteria. The present study outlines the exploration of the genetic basis of competitiveness and antimicrobial activity of a fermented meat isolate, S. shinii IMDO-S216. To this end, its genome was sequenced, de novo assembled, and annotated. RESULTS: The genome contained a single circular chromosome and eight plasmid replicons. Focus of the genomic exploration was on secondary metabolite biosynthetic gene clusters coding for ribosomally synthesized and posttranslationally modified peptides. One complete cluster was coding for a bacteriocin, namely lactococcin 972; the genes coding for the pre-bacteriocin, the ATP-binding cassette transporter, and the immunity protein were also identified. Five other complete clusters were identified, possibly functioning as competitiveness factors. These clusters were found to be involved in various responses such as membrane fluidity, iron intake from the medium, a quorum sensing system, and decreased sensitivity to antimicrobial peptides and competing microorganisms. The presence of these clusters was equally studied among a selection of multiple Staphylococcus species to assess their prevalence in closely-related organisms. CONCLUSIONS: Such factors possibly translate in an improved adaptation and competitiveness of S. shinii IMDO-S216 which are, in turn, likely to improve its fitness in a fermented meat matrix.
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Bacteriocinas , Genoma Bacteriano , Staphylococcus , Staphylococcus/genética , Staphylococcus/metabolismo , Bacteriocinas/genética , Bacteriocinas/metabolismo , Fermentação , Genômica/métodos , Metabolismo Secundário/genética , Carne/microbiologia , Família Multigênica , FilogeniaRESUMO
Seawater warming and marine heatwaves (MHWs) have a major role on the fragmentation and loss of coastal marine habitats. Understanding the resilience and potential for adaptation of marine habitat forming species to ocean warming becomes pivotal for predicting future changes, improving present conservation and restoration strategies. In this study, a thermo-tolerance experiment was conducted to investigate the physiological effects of short vs long MHWs occurring at different timing on recruits of Gongolaria barbata, a canopy-forming species widespread in the Mediterranean Sea. The recruits were collected from a population of the Marine Protected Area of Porto Cesareo (Apulia, Ionian Sea). Recruits length, PSII maximal photochemical efficiency (Fv/Fm), photosynthetic pigments content, concentrations of antioxidant compounds and total antioxidant activity (DPPH) were the response variables measured during the experiment. Univariate asymmetrical analyses highlighted that all physiological variables were significantly affected by both the duration and the timing of the thermal stress with the only exception of recruits length. The higher Fv/Fm ratio, chlorophylls and carotenoids content, and antioxidant compounds concentration in recruits exposed to long-term stress likely indicate an acclimation of thalli to the new environmental conditions and hence, an increased tolerance of G. barbata to thermal stress. Results also suggest that the mechanisms of adaptation activated in response to thermal stress did not affect the natural growth rate of recruits. Overall, this study supports the hypothesis that canopy-forming species can adapt to future climate conditions demonstrating a physiological acclimation to cope with MHWs, providing strong evidence that adaptation of marine species to thermal stress is more frequent than expected, this contributing to design tailored conservation and restoration strategies for marine coastal habitat.
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Alga Marinha , Antioxidantes , Água do Mar , Ecossistema , Mar Mediterrâneo , Mudança ClimáticaRESUMO
Urea is an added value chemical with wide applications in the industry and agriculture. The release of urea waste to the environment affects ecosystem health despite its low toxicity. Online monitoring of urea for industrial applications and environmental health is an unaddressed challenge. Electroanalytical techniques can be a smart integrated solution for online monitoring if sensors can overcome the major barrier associated with long-term stability. Mixed metal oxides have shown excellent stability in environmental conditions with long lasting operational lives. However, these materials have been barely explored for sensing applications. This work presents a proof of concept that demonstrates the applicability of an indirect electroanalytical quantification method of urea. The use of Ti/RuO2-TiO2-SnO2 dimensional stable anode (DSA®) can provide accurate and sensitive quantification of urea in aqueous samples exploiting the excellent catalytic properties of DSA® on the electrogeneration of active chlorine species. The cathodic reduction of accumulated HClO/ClO- from anodic electrogeneration presented a direct relationship with urea concentration. This novel method can allow urea quantification with a competitive LOD of 1.83 × 10-6 mol L-1 within a linear range of 6.66 × 10-6 to 3.33 × 10-4 mol L-1 of urea concentration.
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Nitrogenase is a key player in the global nitrogen cycle, as it catalyzes the reduction of dinitrogen into ammonia. The active site of the nitrogenase MoFe protein corresponds to a [MoFe7S9C-(R)-homocitrate] species designated FeMo-cofactor, whose biosynthesis and insertion requires the action of over a dozen maturation proteins provided by the NIF (for NItrogen Fixation) assembly machinery. Among them, the radical SAM protein NifB plays an essential role, concomitantly inserting a carbide ion and coupling two [Fe4S4] clusters to form a [Fe8S9C] precursor called NifB-co. Here we report on the X-ray structure of NifB from Methanotrix thermoacetophila at 1.95 Å resolution in a state pending the binding of one [Fe4S4] cluster substrate. The overall NifB architecture indicates that this enzyme has a single SAM binding site, which at this stage is occupied by cysteine residue 62. The structure reveals a unique ligand binding mode for the K1-cluster involving cysteine residues 29 and 128 in addition to histidine 42 and glutamate 65. The latter, together with cysteine 62, belongs to a loop inserted in the active site, likely protecting the already present [Fe4S4] clusters. These two residues regulate the sequence of events, controlling SAM dual reactivity and preventing unwanted radical-based chemistry before the K2 [Fe4S4] cluster substrate is loaded into the protein. The location of the K1-cluster, too far away from the SAM binding site, supports a mechanism in which the K2-cluster is the site of methylation.
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Proteínas Arqueais/química , Oxirredutases/química , Proteínas Arqueais/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Cisteína/química , Ácido Glutâmico/química , Histidina/química , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/metabolismo , Methanosarcinales/enzimologia , Modelos Químicos , Oxirredutases/metabolismo , Ligação Proteica , Conformação Proteica , S-Adenosilmetionina/metabolismoRESUMO
OBJECTIVE: The aim of this study is to describe the effectiveness and safety of a magistral formulation of diltiazem 2% rectal gel as a treatment for chronic anal fissure. MATERIAL AND METHODS: A retrospective observational study of all patients that began treatment with diltiazem 2% gel during 2019. The primary endpoint of the study was anal fissure healing. We also looked for differences in effectiveness between those initiating treatment and those who had been previously treated, long-term effectiveness through a 2-year follow-up and frequency of adverse effects. RESULTS: Of the 166 patients included in the study, anal fissure healed in 72.9%. We detected adverse effects in 12 patients, the most common was local irritation. After 2 years of follow-up, 88% of patients did not relapse. CONCLUSION: In this study, use of topical diltiazem 2% has been shown to be effective and safe in the treatment of anal fissure and should be considered as the first line of therapy.
OBJETIVO: El objetivo de este estudio es describir la efectividad y la seguridad de una fórmula magistral de diltiazem 2% gel rectal, como tratamiento de la fisura anal crónica. MATERIAL Y MÉTODOS: Un studio observacional retrospectivo de todos los pacientes que comenzaron a ser tratados con diltiazem 2% gel durante el año 2019. La variable principal del estudio fue la cicatrización de la fisura anal. También se buscaron diferencias de efectividad entre aquellos que iniciaban el tratamiento y los que ya habían sido tratados previamente, efectividad a largo plazo mediante un seguimiento de 2 años y frecuencia de aparición de efectos adversos. RESULTADOS: De los 166 pacientes incluidos en el estudio, el 72,9% cicatrizaron la fisura anal. No detectamos diferencias estadísticamente significativas de efectividad entre los pacientes naive y aquellos que ya habían sido tratados. Detectamos efectos adversos en 12 pacientes, siendo el más frecuente la irritación local. Tras 2 años de seguimiento, el 88% de los pacientes no presentaron ninguna recaída. CONCLUSIÓN: En este estudio, el uso de diltiazem 2% tópico ha mostrado ser efectivo y seguro en el tratamiento de la fisura anal y debería considerarse como primera línea terapéutica.
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Diltiazem , Fissura Anal , Humanos , Diltiazem/uso terapêutico , Diltiazem/efeitos adversos , Fissura Anal/tratamento farmacológico , Fissura Anal/induzido quimicamente , Administração Tópica , Doença Crônica , Cicatrização , Resultado do TratamentoRESUMO
Non-catalytic and catalytic ozonation over Pt/Al2O3 were considered in the treatment of a synthetic effluent composed of six phenolic acids usually present in olive mill wastewaters. In both processes the medium pH affected the rate of ozone decomposition and the formation of hydroxyl radicals. The optimum values were achieved for the catalytic system under pH 7 with 93.0 and 47.7%, respectively, of total phenol content and chemical oxygen demand (COD) removal, after 120 minutes of reaction. For pH 3, the catalytic ozonation followed a free radical pathway perceived by the presence of radical scavengers. No significant structural differences were observed between the fresh and used solid catalyst in X-ray diffraction analysis. Aluminium leaching behaviour was also evaluated at the end of each experiment. Moreover, a sequence of feed-batch trials involving the catalyst reutilization exhibited almost constant activity during the operation time. Eco-toxicological tests were performed for both processes, revealing that the treated effluent still presents some ecological impact, although it is lower than that for the raw wastewater.
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Óxido de Alumínio/química , Ozônio/química , Fenóis/química , Platina/química , Eliminação de Resíduos Líquidos/métodos , Catálise , Concentração de Íons de Hidrogênio , Resíduos Industriais , OleaRESUMO
The current literature lacks a comprehensive discussion on the trade-off between pollutant degradation/mineralization and treatment time costs in utilizing UV light in combination with H2O2-based electrochemical advanced oxidation processes (EAOPs). The present study sheds light on the benefits of using the photoelectro-Fenton (PEF) process with UVA or UVC for methylparaben (MetP) degradation in real drinking water. Although light boosts the photodegradation of refractory Fe(III) complexes and the photolysis of H2O2 (with UVC only), the energy-intensive nature of light-based treatments is acknowledged. To help tackle the high energy consumption issue, a novel approach was employed: partial application of UVA or UVC light after a predetermined electro-Fenton electrolysis time. The proposed treatment approach yielded satisfactory comparable results to those obtained from the application of PEF/UVA or PEF/UVC in terms of total organic carbon removal (ca. 100%), with notably lower energy consumption (ca. 50%). The study delves into the combined method's feasibility, analyzing pollutant degradation/mineralization process and overall energy consumption. The research identifies possible degradation routes based on intermediate detection and radical quenching experiments. Finally, toxicological assessments evaluate the toxicity levels of MetP and its intermediates. The findings of this study bring meaningful contributions to the fore and point to the highly promising potential of the proposed approach, in terms of sustainability and cost-effectiveness, when applied for decentralized water treatment.
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Raios Ultravioleta , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Ferro/química , Técnicas Eletroquímicas/métodos , Poluentes Químicos da Água/análise , Oxirredução , EletrodosRESUMO
Fertilizers play a vital role in the food-energy-water nexus. The traditional method of artificial nitrogen fixation to produce ammonia is a high-energy intensive centralized process that has caused an imbalance of the N-cycle due to the release of N-species to water. Electrocatalytic nitrate reduction (ENR) to ammonia is a promising N-resource recovery alternative that can enable the circular reuse of ammonia in decentralized settings. However, the primary challenge is identifying selective and affordable electrocatalysts. Identifying electrodes that rely on something other than platinum-group metals is required to surpass barriers associated with using expensive and endangered elements. In this study, an earth-abundant bimetallic catalyst, Cu/Co(OH)x, prepared and optimized by electrodeposition, demonstrates superior ammonia production. Under environmentally relevant conditions of 30 mg NO3--N L-1, Cu/Co(OH)x showed higher ammonia production than pristine Cu foam with 0.7 and 0.3 mmol NH3 gcat-1 h-1, respectively. The experimental evaluation demonstrated direct reduction and catalytic hydrogenation mechanisms in Cu/Co(OH)x sites. Leaching analyses suggest that Cu/Co(OH)x has outstanding stability with negligible metal concentration below the maximum contaminant level for both Cu and Co. These results provide a framework for using earth-abundant materials in ENR with comparable efficiency and energy consumption to platinum-group materials.
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Skerpikjøt is a traditionally ripened sheep leg product from the Faroe Islands, constituting a relatively underexplored microbial ecosystem. The objective of this study is to achieve a deeper understanding of the microbial composition of this artisanal product. Nine ripened hind legs, obtained from three different producers, were assessed regarding their bacterial communities and contents of biogenic amines, including both surface and core samples. Biogenic amine concentrations were generally low, although one sample had a somewhat elevated concentration of cadaverine. Bacterial diversity was investigated by culture-dependent and culture-independent techniques. Gram-positive catalase-positive cocci (GCC) constituted the most abundant group. Within this group, Staphylococcus equorum was the most prevailing species, followed by Kocuria sp., Mammaliicoccus vitulinus, and Staphylococcus saprophyticus. Lactic acid bacteria prevailed in only one sample and were mainly represented by Latilactobacillus curvatus. Enterobacterial communities were characterised by the prevalence of Serratia proteamaculans. Despite the majority of GCC, Clostridium putrefaciens was the most abundant bacterial species in some core samples. Taken together, the culture-dependent and culture-independent identification methods gave complementary results.
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Ecossistema , Produtos da Carne , Ovinos , Animais , Produtos da Carne/microbiologia , Fermentação , Bactérias , Lactobacillus , Aminas BiogênicasRESUMO
Water matrix composition impacts water treatment performance. However, matrix composition impacts have rarely been studied for electrochemical water treatment processes, and the correlation between the composition and the treatment efficiency is lacking. This work evaluated the electrochemical reduction of nitrate (ERN) using different complex water matrices: groundwater, brackish water, and reverse osmosis (RO) concentrate/brine. The ERN was conducted using a tin (Sn) cathode because of the high selectivity towards nitrogen evolution reported for Sn electrocatalysts. The co-existence of calcium (Ca2+), magnesium (Mg2+), and carbonate (CO32-) ions in water caused a 4-fold decrease in the nitrate conversion into innocuous nitrogen gas due to inorganic scaling formation on the cathode surface. XRF and XRD analysis of fouled catalyst surfaces detected brucite (Mg(OH)2), calcite (CaCO3), and dolomite (CaMg(CO3)2) mineral scales formed on the cathode surface. Surface scaling created a physical barrier on the electrode that decreased the ERN efficiency. Identifying these main sources of ERN inhibition was key to devising potential fouling mitigation strategies. For this reason, the chemical softening pre-treatment of a real brackish water was conducted and this significantly increased nitrate conversion and faradaic efficiency during subsequent ERN treatment, leading to a lower electric energy consumption per order. Understanding the ionic foulant composition responsible for influencing electrochemically-driven technologies are the first steps that must be taken to move towards niche applications such as decentralized ERN. Thus, we propose either direct ERN implementation in regions facing high nitrate levels in soft waters, or a hybrid softening/nitrate removal system for those regions where high nitrate and high-water hardness appear simultaneously.
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Nitratos , Purificação da Água , Cálcio , Carbonato de Cálcio , Dureza , Magnésio , Hidróxido de Magnésio , Minerais , Nitrogênio , Osmose , EstanhoRESUMO
Boron-doped diamond (BDD) electrodes are regarded as the most promising catalytic materials that are highly efficient and suitable for application in advanced electrochemical oxidation processes targeted at the removal of recalcitrant contaminants in different water matrices. Improving the synthesis of these electrodes through the enhancement of their morphology, structure and stability has become the goal of the material scientists. The present work reports the use of an ultranano-diamond electrode with a highly porous structure (B-UNCDWS/TDNT/Ti) for the treatment of water containing carbaryl. The application of the proposed electrode at current density of 75 mA cm-2 led to the complete removal of the pollutant (carbaryl) from the synthetic medium in 30 min of electrolysis with an electric energy per order of 4.01 kWh m-3 order-1. The results obtained from the time-course analysis of the carboxylic acids and nitrogen-based ions present in the solution showed that the concentrations of nitrogen-based ions were within the established maximum levels for human consumption. Under optimal operating conditions, the proposed electrode was successfully employed for the complete removal of carbaryl in real water. Thus, the findings of this study show that the unique, easy-to-prepare BDD-based electrode proposed in this study is a highly efficient tool which has excellent application potential for the removal of recalcitrant pollutants in water.
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Boro , Poluentes Químicos da Água , Boro/química , Carbaril/análise , Eletrodos , Humanos , Nitrogênio/análise , Oxirredução , Porosidade , Água , Poluentes Químicos da Água/análiseRESUMO
Background: Stress has been associated with food habits. Stress changes eating patterns and the salience and consumption of hyperpalatable foods. During the lock-down due to the COVID-19 pandemic, stress was very common. Objective: We investigated the association between stress and diet quality in Ecuadorian adults during the COVID-19 pandemic. Design: A cross-sectional study. Setting: Data was collected using a self-administered online survey. Stress was measured using the Perceived Stress Scale (PSS-14), and diet quality was evaluated using the Global Diet Index (GDI). A linear regression model with restrictive cubic splines was used to investigate the association between stress and diet quality. Participants: Participants were recruited by convenience sampling, including a total of 2602 individuals. Most participants were female (68.57%) and had university education (78.52%), with a median age of 25 (IQR: 25, 37). Results: Stress was reported by 26.06% of participants. The majority of individuals (75.79%) reported having a diet that needed changes or an unhealthy diet. Independently from biological sex, age, level of education, people/room ratio, economic allowance, and expenses for food, stress was statistically significantly associated with diet quality (p = 0.035). The association between stress and diet quality was inverse and non-linear; higher stress levels were associated with poorer diet quality. The consumption of palatable foods was not statistically significant associated with stress. Conclusions: Stress is associated with poorer diet quality. Public health measures to improve the mental health and lifestyle of the population are needed during the lock-down of the pandemic.
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Bacteriemia/microbiologia , Leucemia Mieloide Aguda/complicações , Nocardiose/complicações , Pneumonia Bacteriana/microbiologia , Bacteriemia/tratamento farmacológico , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Nocardia/isolamento & purificação , Nocardiose/diagnóstico , Nocardiose/tratamento farmacológico , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológicoRESUMO
During spontaneous meat fermentation, diverse microbial communities develop over time. These communities consist mainly of lactic acid bacteria (LAB) and coagulase-negative staphylococci (CNS), of which the species composition is influenced by the fermentation temperature and the level of acidification. Recent development and application of amplicon-based high-throughput sequencing (HTS) methods have allowed to gain deeper insights into the microbial communities of fermented meats. The aim of the present study was to investigate the effect of different fermentation temperatures and acidification profiles on the CNS communities during spontaneous fermentation, using a previously developed amplicon-based HTS method targeting both the 16S rRNA and tuf genes. Spontaneous fermentations were performed with five different lots of meat to assess inter-lot variability. The process influence was investigated by fermenting the meat batters for seven days at different fermentation temperatures (23 °C, 30 °C, and 37 °C) and in the absence or presence of added glucose to simulate different acidification levels. Additionally, the results were compared with a starter culture-initiated fermentation process. The data revealed that the fermentation temperature was the most influential processing condition in shaping the microbial communities during spontaneous meat fermentation processes, whereas differences in pH were only responsible for minor shifts in the microbial profiles. Furthermore, the CNS communities showed a great level of variability, which depended on the initial microbial communities present and their competitiveness.
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Fermentação , Alimentos Fermentados , Microbiologia de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Produtos da Carne , Microbiota , Alimentos Fermentados/microbiologia , Produtos da Carne/microbiologia , Microbiota/genética , RNA Ribossômico 16S/genéticaRESUMO
Most tissue biopsies from patients in hospital environments are formalin-fixed and paraffin-embedded (FFPE) for long-term storage. This fixation process produces a modification in the proteins called "crosslinks", which improves protein stability necessary for their conservation. Currently, these samples are mainly used in clinical practice for performing immunohistochemical analysis, since these modifications do not suppose a drawback for this technique; however, crosslinks difficult the protein extraction process. Accordingly, these modifications make the development of a good protein extraction protocol necessary. Due to the specific characteristics of each tissue, the same extraction buffers or deparaffinization protocols are not equally effective in all cases. Therefore, it is necessary to obtain a specific protocol for each tissue. The present work aims to establish a deparaffinization and protein extraction protocol from FFPE kidney samples to obtain protein enough of high quality for the subsequent proteomic analysis. Different deparaffination, protocols and protein extraction buffers will be tested in FFPE kidney samples. The optimized conditions will be applied in the identification by LC-MS/MS analysis of proteins extracted from 5, 10, and 15 glomeruli obtained through the microdissection of FFPE renal samples.
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Dental caries is an infectious process which ultimately destroys the tooth. Streptococcus mutans is considered to be the main agent causing this disease. If microorganisms with antagonistic action on S. mutans were found, they might provide a way of avoiding or controlling the disease. Within the framework of the Oral Microbial Ecology approach, the aim of this project was to identify S. mutans strains with antagonistic effect upon S. mutans. Saliva samples were taken from 66 children and cultured on Blood agar and Mitis Salivarius Bacitracin agar. They were incubated at 37 degrees C in anaerobic atmosphere for 48 hours, after which bacteria were counted and biochemical tests performed on colonies compatible with S. mutans. Antagonistic effect was determined using the double layer in agar technique. In children without and with caries, the frequency of S. mutans was 91.7% and 96.7%, respectively. In the group of patients without caries, only two strains had no antagonistic action, and three strains had full antagonistic action (100%), while the rest showed different kinds of inhibitory action. In the group of patients with caries, only 5 strains had no antagonistic action, 32 strains had full antagonistic action (100%) and the rest had variable inhibitory action. To conclude, 112 S. mutans strains with high antagonistic potential were identified, which, after other requirements are fulfilled, could be used in caries prevention or control strategies.
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Antibiose , Streptococcus mutans/fisiologia , Criança , Cárie Dentária/prevenção & controle , Humanos , Streptococcus mutans/classificaçãoRESUMO
Peroxi-coagulation (PC) is an interesting new process that has not been widely studied in the literature. This work presents the application of this technology to treat an azo dye synthetic effluent, studying the effect of different parameters including initial pH, current density (j), initial dye concentration and supporting electrolyte. The two former variables significantly affected the colour removal of the wastewater, followed by the initial dye concentration and the kind of electrolyte, in a lesser extent. The optimum operating conditions achieved were initial pH of 3.0, jâ¯=â¯33.3â¯mAâ¯cm-2, 100â¯mgâ¯L-1 of methyl orange (MO) and Na2SO4 as supporting electrolyte. The performance of PC was also compared to other electrochemical advanced processes, under similar experimental conditions. Results indicate that the kinetic decay of the MO increases in the following order: electrocoagulation (EC)â¯<â¯electrochemical oxidation (EO) with electrogenerated H2O2 << PCâ¯<â¯electro-Fenton (EF). This behaviour is given to the high oxidant character of the homogenous OH radicals generated by EF and PC approaches. The EO process with production of H2O2 (EO-H2O2) is limited by mass transport and the EC, as a separation method, takes longer times to achieve similar removal results. Energy requirements about 0.06â¯kWh gCOD-1, 0.09â¯kWh gCOD-1, 0.7â¯kWh gCOD-1 and 0.1â¯kWh gCOD-1 were achieved for PC, EF, EO-H2O2 and EC, respectively. Degradation intermediates were monitored and carboxylic acids were detected for PC and EF processes, being rapidly removed by the former technology. PC emerges as a promising and competitive alternative for wastewaters depollution, among other oxidative approaches.
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Compostos Azo/química , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/química , Eletrodos , Cinética , OxirreduçãoRESUMO
The electrochemical oxidation (EO) of phenolic wastewaters mimicking olive oil mill effluents was carried out in a batch stirring reactor using Ti/IrO2 anodes, varying the nature (NaCl and Na2SO4) and electrolyte concentration (1.8-20 g L-1), current density (57-119 mA cm-2) and initial pH (3.4-9). Phenolic content (TPh) and chemical oxygen demand (COD) removals were monitored as a function of applied charge and over time. The nature of the electrolyte greatly affected the efficiency of the system, followed by the influence of the current density. The NaCl concentration and the initial pH influenced the process in a lesser extent. The best operating conditions achieved were 10 g L-1 of NaCl, current density of 119 mA cm-2 and initial pH of 3.4. These parameters led to 100 and 84.8% of TPh and COD removal, respectively. Under these conditions, some morphological differences were observed by SEM on the surface of the anode after treatment. To study the potential toxicity of the synthetic effluent in neuronal activity, this mixture was applied to rat brain slices prior to and after EO. The results indicate that although the treated effluent causes a smaller depression of the neuronal reactive oxygen species (ROS) signal than the untreated one, it leads to a potentiation instead of recovery, upon washout. Furthermore, the purification of a real olive mill wastewater (OMW), with the organic load of the synthetic effluent, using the same optimised operating conditions, achieved total phenolic compounds abatement and 62.8% of COD removal.This study demonstrates the applicability of this EO as a pre-treatment process of a real effluent, in order to achieve the legal limit values to be discharged into natural streams regarding its organic load.
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Técnicas Eletroquímicas/métodos , Irídio/química , Fenóis , Titânio/química , Poluentes Químicos da Água , Purificação da Água/métodos , Eletrodos , Oxirredução , Fenóis/análise , Fenóis/química , Fenóis/isolamento & purificação , Cloreto de Sódio/química , Sulfatos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificaçãoRESUMO
In order to induce liver hypertrophy to enable liver resection in patients with a small future liver remnant (FLR), various methods have been proposed in addition to portal vein embolisation (PVE). Most recently, the associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) technique has gained significant international interest. This technique is limited by the high morbidity associated with an in situ liver splitting and the patient undergoing two open operations. We present the case of a variant ALPPS technique performed entirely laparoscopically with no major morbidity or mortality. An increased liver volume of 57.9% was seen after 14 days. This technique is feasible to perform and compares favourably to other ALPPS methods whilst gaining the advantages of laparoscopic surgery.