1,867 research outputs found

    Efecto del tipo y cantidad de alúmina como dopante sobre la densificación y las propiedades eléctricas de electrodos cerámicos de óxido de zinc

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    [EN] Aluminum-doped zinc oxide (AZO) electrodes can be a good alternative to replace the expensive electrodes (Ti, ITO, FTO, etc.), which are used in the electrooxidation process to remove refractory and emergent contaminants from industrial wastewaters. AZO electrodes have been prepared by the traditional ceramic method using ZnO as the main raw material and different precursors of Al2O3 as dopant sources. Densification, microstructure and electric resistivity of AZO electrodes are a function of precursor's nature and sintering thermal treatment. The higher the number of precursor's particles and the smaller their size, the sintering temperature needed to attain high densifications and low resistivities shifted to higher values. Micrometric and colloidal alumina were the precursors which allowed to equilibrate an affordable sintering temperature interval (1200-1300 degrees C) with acceptable densification and resistivity values (around 95% and 5 x 10(-3) Omega cm, respectively). However, colloidal alumina made it possible to obtain slightly lower values of resistivity at the cost of having a narrower working interval.[ES] En este trabajo de investigación se presentan electrodos cerámicos de óxido de zinc dopado con aluminio (AZO) como alternativa a los actuales electrodos de titanio (ITO, FTO. . .) utilizados en el proceso de electrooxidación de aguas residuales para la eliminación de contaminantes refractarios y emergentes. Estos electrodos AZO han sido preparados mediante el método tradicional cerámico, utilizando ZnO como materia prima principal y diferentes precursores de Al2O3 como dopantes. La densificación, la microestructura y la resistividad eléctrica de estos electrodos son propiedades que están directamente relacionadas con la naturaleza del precursor y con eltratamiento térmico utilizado para su sinterización. Cuanto mayor es el número de partículas del precursor y menor es su tamano, ¿ la temperatura de sinterización necesaria para lograr altas densificaciones y bajas resistividades cambia a valores más altos. Fueron la alúmina micrométrica y la coloidal los dopantes que ofrecieron un buen equilibrio entre temperatura de sinterización (1.200¿1.300 ¿C) y densificación-resistividad (95% y 5·10¿3 cm, respectivamente). Concretamente en el caso de la alúmina coloidal, se pudieron optimizar estos resultados estrechando el intervalo de temperatura de trabajo.The authors thanks to"Ministerio de Economia y Competitividad" and "Fondo Europeo de Desarrollo Regional" the support to this research [Plan Nacional de I+D, project Ref. CTQ2015-65202-C2-2-R (MINECO/FEDER)].Sánchez-Rivera, M.; Orts, M.; Pérez-Herranz, V.; Mestre, S. (2021). Effect of type and amount of alumina as dopant over the densification and the electrical properties of zinc oxide ceramic electrodes. Boletín de la Sociedad Española de Cerámica y Vidrio. 60(1):53-61. https://doi.org/10.1016/j.bsecv.2020.01.003536160

    Therapeutic drug monitoring of itraconazole and the relevance of pharmacokinetic interactions

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    ABSTRACTA review of the pharmacological aspects of greatest relevance in relation to the monitoring of itraconazole serum levels is presented in this article. The main causes of pharmacokinetic variability, e.g., poor aqueous solubility, the presystemic first-pass effect with the involvement of transporters such as P-glycoprotein, the high extent of metabolism mediated by the CYP450 system and a high probability of pharmacological interactions, are documented and discussed. The pharmacokinetic–pharmacodynamic criteria used to optimise antibiotic therapy, as well as their application to antifungal drugs, are also discussed. Data concerning the breakpoints established for the minimum serum concentrations of itraconazole are included, and the most relevant justifications for drug monitoring are cited

    Feeding entrainment of locomotor activity rhythms, digestive enzymes and neuroendocrine factors in goldfish

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    ©2007. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Accepted version of a Published Work that appeared in final form in Journal of PHYSIOL BEHAV. To access the final edited and published work see http://doi: 10.1016/j.physbeh.2006.10.017L.M. VERA, N. DE PEDRO, E. GÓMEZ-MILÁN, M.J. DELGADO, M.J. SÁNCHEZ MUROS, J.A. MADRID, F.J. SÁNCHEZ-VÁZQUEZ. Feeding entrainment of locomotor activity, digestive enzymes and neuroendocrine factors in goldfish. PHYSIOL BEHAV 90 (2-3) 518-524, 2007. The existence of food anticipatory activity (FAA) in animals subjected to daily feeding schedules seems to be mediated by a feeding-entrainable oscillator (FEO). Such an FEO may help in anticipating meal time and so optimizing food acquisition and nutrient utilization. In this study we investigated the existence of FAA and whether digestive enzymes, plasma cortisol, hypothalamic NPY and gastrointestinal tract (GIT) and plasma melatonin were entrained by periodic feeding in goldfish. We observed that periodically fed goldfish showed FAA in locomotor activity as well as in amylase and NPY. Alkaline protease and GIT melatonin were higher after feeding, whereas plasma cortisol levels were reduced. Plasma melatonin remained unmodified before and after meal time. These results suggested that scheduled feeding entrained both behavioral and certain physiological patterns in goldfish, FAA being of adaptive value to anticipate a meal and prepare the digestive physiology of fish

    Predictors of driving under the influence of alcohol among Spanish adolescents

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    This paper aims to examine the socio-economic determinants of alcohol-impaired drinking in Spanish adolescents. In particular, we are interested in analysing the impact of the family and school environment. To do it, we used the Spanish Survey on Drug Use in the School Population for the year 2008, carried out by the Spanish Government's Delegation for the National Plan on Drugs. This survey with 30,183 students between 14 and 18 years of age (M = 15.6; SD = 1.17) constitutes a representative sample of the Spanish student population. Of these, 6.7% reported having driven under the influence of alcohol, this behaviour being more frequent among boys (10.6%) than girls (2.9%). Logistic regressions reveal that informative campaigns at school could significantly reduce the likelihood of alcohol-impaired driving (OR = 0.82), especially among males (OR = 0.73) and among younger students (OR = 0.66). Our results also suggest that although parents' education has no significant impact, parent's alcohol abuse increase notably the probability of driving after drinking (OR = 2.22 for mothers and OR = 2.81 for fathers). Este artículo pretende analizar los factores socioeconómicos que determinan conducir bajo los efectos del alcohol entre los adolescentes españoles. Particularmente, estamos interesados en analizar el impacto del entorno familiar y escolar. Para ello, utilizamos la Encuesta sobre Drogas en Población Escolar, correspondiente al año 2008, llevado a cabo por el Plan nacional sobre drogas del Gobierno de España. Este estudio con 30.183 estudiantes de edades comprendidas entre los 14 y los 18 años (M = 15.6; DT = 1.17), constituye una muestra representativa de dicha población estudiantil española. De ellos, el 6,7% afirmaron haber conducido bajo los efectos del alcohol, siendo esta conducta más frecuente entre los chicos (10,6%) que entre las chicas (2,9%). Regresiones logísticas revelan que las campañas informativas realizadas en los colegios reducen significativamente la probabilidad de conducir bebido (OR = 0,82), particularmente entre los chicos (OR = 0,73) y entre los estudiantes más jóvenes (OR = 0,66). Nuestros resultados también sugieren que aunque la educación de los padres tiene poco impacto, el consumo abusivo de alcohol por parte de los padres incrementa notablemente la probabilidad de conducir bebido (OR = 2.22 para las madres y OR = 2,81 parar los padres)

    Spatial distribution and intra-annual variability of water masses on the Eastern Gulf of Cadiz seabed

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    This paper presents the spatial distribution and intra-annual variability of seabed hydrography in the Eastern Gulf of Cadiz based on more than 10 years of near-bottom CTD observations. Well-defined water masses and a variety of mixing products are persistently sorted along three bathymetric areas occupying particular depth intervals: (i) inner shelf waters (<60 m depth), with strong coastal and atmospheric influence; (ii) low-salinity Eastern North Atlantic Central Waters (ENACW) related to the Gulf of Cadiz Current (GCC) along the central and outer shelf (between 100 and 250 m depth); and (iii) a range of salinity and temperature flavors associated with the dense Mediterranean Outflow Water (MOW) occupying the deeper grounds. All three are characterized by significant March– November hydrographic differences suggesting an intra-annual variability pattern. After summer heating and stratification of the water column, warm (17.8 °C) and saline (36.26) waters occupy the inner-shelf in November whereas cooler (14.6 °C) and less saline (36.17) waters occur in March as the combined result of the erosion of the seasonal thermocline and intensified continental runoff. Offshore, colder, more saline and hence denser MOW invades the upper slope in March diluting the easternmost tip of a saltier ENACW wedge and nudging its outer rim up onto the shelf. This narrows and constricts the GCC band in winter, while its bottom trace appears to broaden and stretch eastwards in November. More effective MOW-ENACW mixing west of the Strait of Gibraltar driven both by an elevated MOW and a less stratified ENACW could explain the winter salinification of most of the grounds deeper than 250 m.En prensa2,088
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