144 research outputs found

    Kinetic Modeling of the UV/H2O2 Process: Determining the Effective Hydroxyl Radical Concentration

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    A kinetic model for pollutant degradation by the UV/H2O2 system was developed. The model includes the background matrix effect, the reaction intermediate action, and the pH change during time. It was validated for water containing phenol and three different ways of calculating HO° level time-evolution were assumed (non-pseudo-steady, pseudo-steady and simplified pseudo-steady state; denoted as kinetic models A, B and C, respectively). It was found that the kind of assumption considered was not significant for phenol degradation. On the other hand, taking into account the high levels of HO2° formed in the reaction solution compared to HO° concentration (~10–7 M >>>> ~10–14 M), HO2° action in transforming phenol was considered. For this purpose, phenol-HO2° reaction rate constant was calculated and estimated to be 1.6x103 M-1 s-1, resulting in the range of data reported from literature. It was observed that, although including HO2° action allowed slightly improving the kinetic model degree of fit, HO° developed the major role in phenol conversion, due to their high oxidation potential. In this sense, an effective level of HO° can be determined in order to be maintained throughout the UV/H2O2 system reaction time for achieving an efficient pollutant degradation

    Sensitive spectrophotometric determination of hydrogen peroxide in aqueous samples from advanced oxidation processes: Evaluation of possible interferences

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    Hydrogen peroxide (H2O2) determination in real watersamples was carried out in a simple and sensitiveway. The resulting optimal operating conditions froma 23 full factorial experimental design were 450 nm, 50mm and 6x10-3 M for the absorption wavelength, thequartz cell path length and the final concentration ofthe ammonium monovanadate solution, respectively;allowing the quantification of H2O2 up to 2.94x10-3mM. The proposed analytical method was validatedand the effect of the background matrix was investigated,obtaining a selective method. Additionally, thedeveloped analytical method was applied for studyingthe evolution of H2O2 in the decontamination of watercontaining 6.73x10-5 mM of anthracene and 1.19x10-5mM of benzo[a]pyrene using the UV/H2O2 system. Itwas found that the optimal H2O2 level enabling about45% of mineralisation and a removal of the targetpolycyclic aromatic hydrocarbons higher than 99%was 2.94x10-1 mM, remaining approximately 1.47x10-1 mM of H2O2 after 90 min of treatment

    A Pea (Pisum sativum L.) Seed Vicilins Hydrolysate Exhibits PPARγ Ligand Activity and Modulates Adipocyte Differentiation in a 3T3-L1 Cell Culture Model

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    © 2020 by the authors.Legume consumption has been reported to induce beneficial effects on obesity-associated metabolic disorders, but the underlying mechanisms have not been fully clarified. In the current work, pea (Pisum sativum L.) seed meal proteins (albumins, legumins and vicilins) were isolated, submitted to a simulated gastrointestinal digestion, and the effects of their hydrolysates (pea albumins hydrolysates (PAH), pea legumins hydrolysates (PLH) and pea vicilin hydrolysates (PVH), respectively) on 3T3-L1 murine pre-adipocytes were investigated. The pea vicilin hydrolysate (PVH), but not native pea vicilins, increased lipid accumulation during adipocyte differentiation. PVH also increased the mRNA expression levels of the adipocyte fatty acid-binding protein (aP2) and decreased that of pre-adipocyte factor-1 (Pref-1) (a pre-adipocyte marker gene), suggesting that PVH promotes adipocyte differentiation. Moreover, PVH induced adiponectin and insulin-responsive glucose transporter 4 (GLUT4) and stimulated glucose uptake. The expression levels of peroxisome proliferator-activated receptor γ (PPARγ), a key regulator of adipocyte differentiation, were up-regulated in 3T3-L1 cells treated with PVH during adipocyte differentiation. Finally, PVH exhibited PPARγ ligand activity. Lactalbumin or other pea hydrolysates (PAH, PLH) did not exhibit such effects. These findings show that PVH stimulates adipocyte differentiation via, at least in part, the up-regulation of PPARγ expression levels and ligand activity. These effects of PVH might be relevant in the context of the beneficial health effects of legume consumption in obesity-associated metabolic disorders.This work was carried out with financial support from the Spanish MICIIN (PET2008-0311 and AGL2017-83772-R). This research has been also partially supported by the FEDER and FSE funds from the European Union.Peer reviewe

    Determinación espectrofotométrica sensible del peróxido de hidrógeno en muestras de agua procedentes de procesos de oxidación avanzada : Evaluación de posibles interferencias

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    RESUMEN: La determinación de peróxido de hidrógeno (H2O2) en muestras de agua real se llevó a cabo de una manera sencilla y sensible. Las condiciones óptimas de funcionamiento resultantes de un diseño experimental factorial completo fueron 450 nm, 50 mm y 6 x 10-3 M de longitud de onda de absorción, longitud de trayectoria de la celda de cuarzo y concentración final de la solución de monovanadato de amonio, respectivamente; permitiendo la cuantificación de 2.94x10-3 mM de H2O2. Se validó el método analítico propuesto y se investigó el efecto de la matriz obteniendo un método selectivo. Además, se aplicó el método analítico desarrollado para estudiar la evolución de H2O2 en la descontaminación de agua que contenía 6,73x10-5 mM de antraceno y 1,19x10-5 mM de benzo[a]pireno utilizando el sistema UV/H2O2. Se encontró que el nivel óptimo de H2O2 que permitía cerca del 45% de mineralización y una eliminación de los hidrocarburos aromáticos policíclicos objeto de estudio superior al 99% fue de 2,94x10-1 mM, permaneciendo aproximadamente 1,47x10-1 mM de H2O2 después de 90 min de tratamiento.ABSTRACT: Hydrogen peroxide (H2O2) determination in real water samples was carried out in a simple and sensitive way. The resulting optimal operating conditions from a 23 full factorial experimental design were 450 nm, 50 mm and 6x10-3 M for the absorption wavelength, the quartz cell path length and the final concentration of the ammonium monovanadate solution, respectively; allowing the quantification of H2O2 up to 2.94x10-3 mM. The proposed analytical method was validated and the effect of the background matrix was investigated, obtaining a selective method. Additionally, the developed analytical method was applied for studying the evolution of H2O2 in the decontamination of water containing 6.73x10-5 mM of anthracene and 1.19x10-5 mM of benzo[a]pyrene using the UV/H2O2 system. It was found that the optimal H2O2 level enabling about 45% of mineralisation and a removal of the target polycyclic aromatic hydrocarbons higher than 99% was 2.94x10-1 mM, remaining approximately 1.47x10-1 mM of H2O2 after 90 min of treatment

    A Novel Cause-Effect Variable Analysis in Enterprise Architecture by Fuzzy Logic Techniques

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    In this paper, or present a new integration approach for managing Information Technology variables within enterprise architecture in an integrated way. Additionially, a novel method based on fuzzy logic for cause-effect variable analysis is proposed as a useful support decision-making tool for companies in order to lmow the main actions they must perform for increasing their benefits. This is employed to assess the Integration Management System in Enterprises, based on Enterprise Architecture and Information Technology. We show as fuzzy logic plays an important role M this area due to these variables can be affected for multifactorial elements iinpregnated with uncertainty. The knowledge given by the experts is translated into dependence rules, Which have also been analyzed from a fuzzy point of view using a combination of two fuzzy techniques, namely, fuzzy relation equation theory and fuzzy graph. Firstly, fuzzy dependence rules are computed froth fuzzy relation equations and, secondly an analysis based on incidence subgraph is performed. The resulLisa strategic plan automatically generated from the data captured of each enterprise in which the most import variables to be improved are detailed. (C) 2020 The Authors. Published by Atlantis Press SARI.

    Application of Fenton process for treating petrochemical wastewater.

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    Este artículo hace una revisión sobre las aplicaciones del proceso Fenton para el tratamiento de aguas residuales procedentes de la industria petroquímica. En él se describe brevemente el mecanismo de reacción y se analizan las principales variables que influyen en la eficiencia de este proceso (concentración del agente oxidante y del catalizador, temperatura, pH, tiempo de reacción, tipo de contaminante y presencia de aniones). Asimismo, se detallan diversos estudios que evalúan la viabilidad del sistema Fenton en la degradación de sustancias derivadas del petróleo, sus limitaciones y las perspectivas de futuro. Abstract This article reviews the application of Fenton process to treat wastewater from the petrochemical industry. The reaction mechanism is briefly described, and the main variables that influence the efficiency of this process are analyzed (oxidizing agent and catalyst level, temperature, pH, reaction time, type of pollutant and the presence of anions). Additionally, several studies evaluating the feasibility of the Fenton system in the degradation of oil-derived substances are described, as well as Fenton process’ limitations and future perspectives

    Isokinetic leg strength and power in elite handball players

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    Isokinetic strength evaluation of the knee flexion and extension in concentric mode of contraction is an important part of the comprehensive evaluation of athletes. The aims of this study were to evaluate the isokinetic knee peak torque in both the extension and flexion movement in the dominant and non-dominant leg, and the relationship with jumping performance. Twelve elite male handball players from the top Spanish handball division voluntary participated in the study (age 27.68 ± 4.12 years; body mass 92.89 ± 12.34 kg; body height 1.90 ± 0.05 m). The knee extensor and flexor muscle peak torque of each leg were concentrically measured at 60º/s and 180º/s with an isokinetic dynamometer. The Squat Jump and Countermovement Jump were performed on a force platform to determine power and vertical jump height. Non-significant differences were observed between legs in the isokinetic knee extension (dominant= 2.91 ± 0.53 Nm/kg vs non-dominant = 2.70 ± 0.47 Nm/kg at 60º/s; dominant = 1.90 ± 0.31 Nm/kg vs non-dominant = 1.83 ± 0.29 Nm/kg at 180º/s) and flexion peak torques (dominant = 1.76 ± 0.29 Nm/kg vs non-dominant = 1.72 ± 0.39 Nm/kg at 60º/s; dominant = 1.30 ± 0.23 Nm/kg vs non-dominant = 1.27 ± 0.35 Nm/kg at 180º/s). Low and non-significant correlation coefficients were found between the isokinetic peak torques and vertical jumping performance (SJ = 31.21 ± 4.32 cm; CMJ = 35.89 ± 4.20 cm). Similar isokinetic strength was observed between the legs; therefore, no relationship was found between the isokinetic knee flexion and extension peak torques as well as vertical jumping performance in elite handball players.Actividad Física y Deport

    On the incorporation of interval-valued fuzzy sets into the Bousi-Prolog system: declarative semantics, implementation and applications

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    In this paper we analyse the benefits of incorporating interval-valued fuzzy sets into the Bousi-Prolog system. A syntax, declarative semantics and im- plementation for this extension is presented and formalised. We show, by using potential applications, that fuzzy logic programming frameworks enhanced with them can correctly work together with lexical resources and ontologies in order to improve their capabilities for knowledge representation and reasoning

    Evaluación y rehabilitación neuropsicológica en oncología pediátrica.

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    Objetivo. El presente trabajo tiene como objetivo el estudio de los efectos neuropsicológicos a largo plazo del cáncer infantil y sus tratamientos así como plantear propuestas para la rehabilitación cognitiva. Método. El método ha consistido en una revisión sistemática de los resultados en la literatura científica acerca de los efectos de la quimioterapia y la radioterapia sobre el SNC y en las funciones cognitivas y conductuales detectados a través de estudios de neuroimagen como calcificaciones y cambios en la sustancia blanca. Presentamos, además, el protocolo de evaluación neuropsicológica ejemplificado con un diagnóstico frecuente que presenta deterioro generalizado. Proponemos un programa de rehabilitación neuropsicológica basado en el Attention Process Training (APT) de Mateer y Sohlberg. Resultado. La radioterapia craneal y el metotrexato producen alteraciones generalizadas que se reflejan en déficit neuropsicológicos: CI, atención, memoria, habilidades académicas y motoras. Conclusiones. El avance en los tratamientos ha supuesto la disminución del número e intensidad de las secuelas. No obstante, sigue siendo frecuente que en los tumores del SNC y en las leucemias aparezcan alteraciones cognitivas y conductuales. La evaluación neuropsicológica continua y los modelos de sustancia blanca nos ayudan a entender estos efectos a largo plazo. Asimismo, esta evaluación es fundamental para diagnosticar los déficit evitando falsas atribuciones y expectativas inadecuadas. Destacamos la necesidad de una unidad de seguimiento y del trabajo interdisciplinario para promover la calidad de vida de los niños con cáncer
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