Competition between tunnel- and viscosity-effects on bimolecular hydrogen-transfer reaction

The photocyclization of a methylsubstituted diphenylamine results in the formation of a transient zwitterionic dihydrocarbazole. The transient converts into a stable dihydrocarbazole by an intramolecular, sigmatropic hydrogen shift and by an intermolecular hydrogen exchange reaction. The rates of both reactions are governed by hydrogen tunnel effects. The intermolecular hydrogen exchange is the first example for a bimolecular reaction where tunnel effects have been observed. The role of solvent viscosity is discussedS

Capital regulatorio y capital económico : prociclicidad del nuevo Acuerdo de Capital y análisis de escenarios de crisis

Artículo de revistaEn 1998, el Comité de Supervisión Bancaria de Basilea inició los trabajos para una profunda revisión del Acuerdo de Capital de 1988, actualmente en vigor. Durante este tiempo, el Comité ha sometido a consulta dos propuestas, en junio de 1999 y enero de 2001, para recabar la opinión de los distintos agentes implicados. Una tercera, y última, consulta se realizará durante el año 2002, antes de la publicación del Acuerdo final, que previsiblemente entrará en vigor en el 2005. Los intensos debates y comentarios que han suscitado las propuestas del Comité ya constituyen en sí mismos el primer logro, antes de nacer, del nuevo Acuerdo, al haber contribuido a la difusión y desarrollo de todos los temas relativos al control, medición y gestión de los diferentes tipos de riesgo, y de forma especial del riesgo de crédito

Presencia del virus del nilo occidental en equinos (Equus caballus) de dos humedales de la Provincia de los Ríos, año 2007 al 2009

In orden to know the presence of West Nile Virus (WNV) in horses of Ecuador. Was investigated in: The Abras de Mantequilla and Jauneche. For the theme of this research is first conducted a census of the equine population in the areas studied, which was 273 animals. Then the samples were taken, later to be processed on the thread of Virology, National Institute of Hygiene and Tropical Medicine “Leopoldo Izquieta Perez” for the determination of antibodies to WNV by ELISA. The reactive samples were sent to the CDC in Puerto Rico to be confirmed by neutralization test by reducing the number of plates (NTRP). Of the 189 samples tested, 15 were reactive by ELISA of which 5 were confirmed by (NTRP).Con el propósito de conocer la presencia del Virus del Nilo Occidental (VNO) en Equinos del Ecuador se investigó en: Las Abras de Mantequilla y Jauneche. Para la temática de esta investigación primero se realizó un censo de la población equina en las zonas a estudiar qué fue de 273 animales. Luego se tomaron las muestras, para después ser procesadas en el Subproceso de Virología del Instituto Nacional de Higiene y Medicina Tropical “Leopoldo Izquieta Pérez” para la determinación de anticuerpos contra el VNO mediante la técnica de ELISA. Las muestras reactivas por ELISA fueron enviadas al CDC de Puerto Rico para ser confirmadas por la prueba de Neutralización por Reducción del Número de Placas (NTRP). De las 189 muestras analizadas, 15 resultaron reactivas por la técnica de ELISA de ellas 5 se confir maron por NTRP

Comparing risk-weighted assets: the importance of supervisory validation processes

Artículo de revistaThis article analyses the problems of using the risk-weighted assets (RWA) density ratio – defined as the ratio of RWA to total assets – to make comparisons across banks, as is frequently done by banks themselves and analysts. An international comparison is made of 16 European banks, based on public information, from which it is concluded that a significant part of the differences in RWA density are a consequence of differences in the type of business involved. In particular, the greater the weight of credit risk in a bank’s balance sheet the higher will be its RWA density. We propose alternative RWA density ratios and illustrate them with the results for Spanish banks using confidential data. We show that public information cannot be sufficiently detailed to enable differences across banks arising from their risk profiles to be distinguished from others attributable, for example, to different interpretations of solvency rules by banks or supervisors. Therefore, the supervisory review process and the progress in its inter-jurisdictional harmonisation are especially important. The paper concludes with a review of the process used by the Banco de España for the supervisory validation of Internal Ratings Based (IRB) approaches for credit risk

Fluorescence of methylated derivatives of hydroxyphenylimidazopyridine. Resolution of strongly overlapping spectra and a new ESIPT dye showing very efficient radiationless deactivation

This is the peer-reviewed version of the following article: Fluorescence of methylated derivatives of hydroxyphenylimidazopyridine. Resolution of strongly overlapping spectra and a new ESIPT dye showing very efficient radiationless deactivation Alfonso Brenlla, Manoel Veiga, M. Carmen Ríos Rodríguez, Manuel Mosquera and Flor Rodríguez-Prieto Photochem. Photobiol. Sci., 2011, 10, 1622. DOI: 10.1039/c1pp05165b, which has been published in final form at http://pubs.rsc.org/en/content/articlelanding/2011/pp/c1pp05165b This article may be used for non-commercial purposes onlyThe ground- and excited-state behaviour of the isomeric species 2-(2′-methoxyphenyl)imidazo[4,5-b]pyridine (1-OMe) and 2-(2′-hydroxyphenyl)-4-methylimidazo[4,5-b]pyridine (1-NMe) in neutral and acid media has been studied by UV-vis absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy. The new dye 1-NMe is non-fluorescent in neutral media except in trifluoroethanol, where it shows a very weak fluorescence. 1-NMe also exhibits highly solvent-dependent fluorescence intensity in acidic media. We propose that the neutral species experiences a fast excited-state intramolecular proton transfer (ESIPT), relaxing afterwards by intramolecular twisting associated with internal charge transfer (TICT) and subsequent very fast internal conversion of the proton-transferred TICT structure. The behaviour of 1-NMe in acidic media is explained by the existence of a ground-state tautomeric equilibrium between species with intramolecular hydrogen bonds N–H⋯OH and N⋯HO. The first type of tautomers dissociates at the hydroxyl group in water and ethanol, but fluoresces in acetonitrile and trifluoroethanol due to the inability of these solvents to accept the proton. The second type of tautomers is non-emissive due to fast radiationless deactivation through an ESIPT-TICT process. The fluorescence of 1-OMe was investigated in neutral and acidic media, demonstrating the photobasic character of the pyridine nitrogen. A ground-state equilibrium between pyridinium and imidazolium cations was found for this species, showing overlapping absorption and fluorescence spectra. We devised a method to resolve the spectra by applying principal component global analysis to a series of excitation spectra taken at different emission wavelengths, which allowed estimation of the equilibrium constant between the cationsWe are indebted to the Spanish Ministry of Education and Science and the European Regional Development Fund (Grants CTQ2007-68057-C02-01/BQU and CTQ2010-17835) and the Xunta de Galicia (Grant IN845B-2010/094) for financial support of our work. A. Brenlla thanks the Fundación Segundo Gil Dávila for a postgraduate research grantS

Innovación Docente en Historia Económica en el EEES

El Proyecto de Innovación Docente se aplicó sobre 450 alumnos de la asignatura de Historia Económica en el primer curso del Grado de Finanzas y Contabilidad. En esta asignatura se había utilizado tradicionalmente una metodología basada en clases magistrales con el apoyo de lecturas y materiales complementarios. El proyecto docente introducía una metodología de enseñanza mixta utilizando la plataforma virtual de la Universidad de Sevilla. A través de esta plataforma se realizaron actividades presenciales y también de e-learning en la web. La temática principal de estas actividades se centró en las crisis económicas. Esto se concretó a partir de estudio de casos: la crisis finisecular del siglo XIX, la crisis de 1929 y las crisis de finales del siglo XX y principios del XXI (crisis del petróleo de 1973, crisis financiera de los años 90 y la crisis económica actual). A través del material aportado por el profesor en la red y en las actividades complementarias presenciales (prensa, lecturas de historia económica y documentales) se establecen las causas, efectos y aspectos comunes y diferenciales de estas crisis.The Teaching Innovation Project was applied to 450 students of the Subject of Economic History of the first year of the Finance and Accounting Degree. This topic had used to be a traditional method based on master classes with the support of complementary readings and dossiers. Teaching project introduced a blended learning using the University of Seville web site. Through this platform and attending classes were also e-learning. The main topic of these activities are focused on the economic crisis with cases studies: the crisis of 1873, the Great Depression of 1929, the crisis of 1973 oil crisis, financial crisis 90’s years and the current economic crisis. Through the network materials, and exercises in class (press, reading of economic history and documentaries are established the causes, effects and common and differents aspects of these crisis

Aspectos críticos en la implantación y validación de modelos internos de riesgo de crédito

Artículo de revistaEl artículo analiza algunos aspectos que la experiencia acumulada en la revisión supervisora ha revelado como críticos en la implantación y validación de los modelos internos de riesgo de crédito. Se destaca la importancia tanto de los factores cualitativos como de los detalles en los cálculos numéricos que conducen a la cifra de capital regulatorio. Dentro de los aspectos cualitativos, se señalan aquellos en los que en la práctica se han detectado más problemas o cuya solución puede ser muy costosa en términos de recursos y tiempo. Entre otros, se destacan: la integración efectiva de los modelos en la gestión diaria de los riesgos, la implicación de la alta dirección y la existencia de bases de datos adecuadas. Para poner de manifiesto la importancia de los detalles en los cálculos de capital regulatorio, se analiza el impacto de la construcción de las categorías de riesgo, el ajuste al ciclo y la posible correlación entre probabilidades de incumplimiento y severidades. Por último, se hace referencia a un caso particular en el que la estimación de los factores de riesgo adquiere una especial dificultad, el de las carteras con pocos incumplimientos

Strong Metal-Support Interaction (SMSI) in Au/TiO2 photocatalysts for environmental remediation applications: Effectiveness enhancement and side effects

Strong Metal−Support Interaction (SMSI) is a well-known phenomenon of heterogeneous catalysis that have not been extensively investigated in photocatalytic applications. Moreover, the reactions previously studied for photocatalysts under SMSI state are mainly restricted to energy related uses. The present work seeks to explore the effect of SMSI induced by soft wet-chemistry in a Au/TiO2 photocatalyst with specific focus on photocatalytic environmental remediation. With this aim, the developed photocatalyst has been evaluated considering liquid, gas and solid pollutants in order to represent the wide range of environmental photocatalysis applications. These photooxidation scenarios were methylene blue dissolved in water, gaseous NO, and soot directly deposited on the photocatalyst. The results revealed that the SMSI induction has a generally positive effect on photoactivity promoting the MB and soot removal by 53% and 60%, respectively. However, the SMSI did not provide any additional benefit in the NOx elimination compared to the non-SMSI Au/TiO2 photocatalyst, because the enveloping of AuNPs limits the gold-pollutant interaction

Studying the bulk hydrophobization of cement mortars by the combination of alkylalkoxysilane admixture and fluoropolymer-functionalized aggregate

In this work, hydrophobic mortars are produced by combining a silane-based admixture with the pre-treatment of the aggregates with an alkoxysilane-ended fluoropolymer. A comparative study is presented to determine the effect of the components, under different curing conditions, on the hydrophobicity, mechanical performance, composition and micro-structure. The combination of both strategies allows obtaining hydrophobic properties at different curing conditions, whereas the silane loses effectiveness at high humidity and the modified aggregate at low humidity. The silane hinders cement hydration and promotes gaps in the aggregate-matrix interfacial transition zone, decreasing mechanical resistance, whereas the modified aggregate changes the interfacial transition zone morphology without significant effects on resistance. The combination of both strategies partially compensates the negative impact of the silane admixture, especially when the mortars are cured at high humidity. Thus, this combination increases versatility of the mortars and poses as a potential route to address the limitations of silane admixtures. © 2022 The Author

PoS tagging and Named Entitiy Recognition in a Big Data environment

Este artículo describe una suite de módulos lingüísticos para el castellano, basado en una arquitectura en tuberías, que incluye tareas de análisis morfosintáctico así como de reconocimiento y clasificación de entidades nombradas. Se han aplicado técnicas de paralelización en un entorno Big Data para conseguir que la suite de módulos sea más eficiente y escalable y, de este modo, reducir de forma significativa los tiempos de cómputo con los que poder abordar problemas a la escala de la Web. Los módulos han sido desarrollados con técnicas básicas para facilitar su integración en entornos distribuidos, con un rendimiento próximo al estado del arte.This article describes a suite of linguistic modules for the Spanish language based on a pipeline architecture, which contains tasks for PoS tagging and Named Entity Recognition and Classification (NERC). We have applied run-time parallelization techniques in a Big Data environment in order to make the suite of modules more efficient and scalable, and thereby to reduce computation time in a significant way. Therefore, we can address problems at Web scale. The linguistic modules have been developed using basic NLP techniques in order to easily integrate them in distributed computing environments. The qualitative performance of the modules is close the state of the art.Este trabajo ha sido subvencionado con cargo a los proyectos HPCPLN - Ref:EM13/041 (Programa Emergentes, Xunta de Galicia), Celtic - Ref:2012-CE138 y Plastic - Ref:2013-CE298 (Programa Feder-Innterconecta)