Supersymmetric Baryonic Branes

We derive an energy bound for a `baryonic' D5-brane probe in the $adS_5\times S^5$ background near the horizon of $N$ D3-branes. Configurations saturating the bound are shown to be 1/4 supersymmetric $S^5$-wrapped D5-branes, with a total Born-Infeld charge $N$. Previous results are recovered as a special case. We derive a similar energy bound for a `baryonic' M5-brane probe in the background of $N$ M5-branes. Configurations saturating the bound are again 1/4 supersymmetric and, in the $adS_7\times S^4$ near-horizon limit, provide a worldvolume realization of the `baryon string' vertex of the (2,0)-supersymmetric six-dimensional conformal field theory on coincident M5-branes. For the full M5-background we find a worldvolume realization of the Hanany-Witten effect in M-theory.Comment: 32 pp. Third version is the same as the second except for a little additional material. To appear in JHE

Cuestiones conflictivas en relación con los principios en material tributaria

El presente trabajo pretende abordar el papel esencial de los principios constitucionales tributarios, y en especial, el principio de no confiscatoriedad, a la hora de evitar que las distintas administraciones públicas implanten políticas tributarias injustas, con el estudio detallado y análisis jurisprudencial que los órganos jurisdiccionales y, en especial, el Tribunal Constitucional, han venido desarrollando en defensa del contribuyente, a los efectos de garantizar sus derechos. A tal efecto, nos centraremos a lo largo de este trabajo en las posibles vulneraciones sufridas y de un modo más concreto, analizaremos la quiebra del principio de capacidad económica en la normativa reguladora del IIVTNU, que ante la STC 59/2017 hubo de ser modificada por el Gobierno. Estos derechos de los que hablamos son precisamente los principios tributarios consagrados en el artículo 31 de la CE y que son recogidos posteriormente en el artículo 3 de la LGT, adquiriendo por sí mismos un valor jurídico trascendental y cuya interrelación resulta evidente con el objetivo de lograr un sistema tributario justo suponiendo la base y el instrumento necesario del que disponen los Tribunales para asegurar así la efectiva aplicación de los derechos del contribuyente

Differentiation between copal and amber by their structure and thermal behaviour

The relationships between the polymerization related to structure and the composition of different types of natural resins were determined. Analyses were carried out by Fourier transform infrared spectroscopy (FTIR), differential thermal analysis–thermogravimetry (DTA-TG) and hot stage microscopy (HSM). Copal specimens were collected from the Mai-Ndombe Lake, Democratic Republic of Congo, and amber pieces that came from Bitterfeld, Germany, and from Kaliningrad, Russia. FTIRspectra of copal show a vibrational band at 1643 cm−1 (C=O stretching) attributed to communic acids, while amber shows a band at 1735 cm−1 associated with ester-group vibrations and a shoulder at about 3340 cm−1, suggesting partial oxidization.DTA shows the main exothermic peak, related to the combustion, at 546–552 °C in amber and at 518 °C in copal. The derivative thermogravimetry (DTG) peaks vary in the different resin types; in amber, they occur at 333–335, 401–404 and 548–555 °C and are related to mass losses of 31, 26 and 39 mass%, respectively; copal peaks are at 394 and 507 °C, with mass losses of 71 and 27 mass%, respectively. In copal, hot stage microscopy (HSM) shows the start of sintering at 131 °C, followed by an expansion produced by the material decomposition and the generation of gases that cannot be released because of the material plastic behaviour. Finally, the increase in pressure produces an explosion that results in a lower viscosity of the liquid, which at this point can no longer support the internal pressure of gases. In amber samples, a smaller decrease in viscosity is observed and the start of sintering occurs at 150 °C with no significant change in their morphology.</p

Sinergias Entre el Modelo de Mezclas Espectrales y el Análisis de Imágenes Basado en Objetos en el Estudio de Incendios ForestalesSynergies Between Linear Spectral Mixture Analysis and Object-Based Image Analysis to Study Forest Fires

Las metodologías unitemporales habitualmente utilizadas para cartografiar el área afectada por un incendio forestal se basan en la clasificación de una imagen NDVI post-incendio; sin embargo, presentan algunas limitaciones. Este trabajo propone una metodología basada en el empleo conjunto del Modelo de Mezclas Espectrales (Spectral Mixture Analysis - SMA) y el análisis de imágenes basado en objetos (Object-Based Image Analysis - OBIA), con la finalidad de minimizar estos problemas. Por una parte, SMA, que trabaja a nivel subpíxel, posibilita minimizar las confusiones originadas por la influencia del suelo; y, por otra, OBIA, trabajando a nivel suprapíxel, permite considerar características no espectrales tales como la forma y la textura. La imagen fracción vegetación quemada, obtenida al descomponer espectralmente una imagen Landsat Enhanced Thematic Mapper Plus, ETM+, posterior al incendio considerado, fue la entrada de un clasificador orientado a objetos que empleó dos niveles de segmentación. La precisión de los resultados obtenidos utilizando esta metodología en el incendio ocurrido entre los días 13 y 17 de septiembre de 1998 en Tabuyo del Monte – LeónEspaña (3.309 ha), es muy prometedora, indicando sinergias entre ambos métodos, y con un gran potencial para la cartografía de áreas quemadas y estimación de niveles de severidad.Abstract Unitemporal methodologies used to mapping burned area are usually based on post fire NDVI image classification; nevertheless they present several limitations. In order to minimize these deficiencies, this work shows a methodology based on Spectral Mixture Analysis (SMA) and Object-Based Image Analysis (OBIA). On the one hand, SMA, working at subpixel level, permits minimise the errors due to soil influence. On the other hand, OBIA, working at suprapixel scale, allows to consider not only spectral characteristics but also form and texture. The burned vegetation fraction image, obtained by unmixing a Landsat Enhanced Thematic Mapper Plus (ETM+) post fire image, was the input to a two segmentation levels OBIA. The results acuracy obtained applying this methodology on the study of the forest fire occurred between 13th-17th September 1998 in Tabuyo del Monte (León-Spain) (3,309 ha) was very promising, showing synergies between SMA and OBIA and a great potential to burned area mapping and severity estimation

Pasado y presente: innovación docente y las crisis financieras en España 1850-2014

L’objectiu d’aquest treball és doble. D'una banda, analitzar els avantatges i limitacions de les Tecnologies de la Informació i Comunicació (TICs) en l'ensenyament de la història econòmica. Per aquest motiu, primer descrivim algunes de les mesures adoptades dins l'Àrea d'Història i Institucions Econòmiques de la Universitat de València. De l'altra, explicar mitjançant l'exposició d'una pràctica concreta, com hem tractat de combinar diferents metodologies per estimular la motivació de l'alumne, el treball en grup, i l'estudi autònom. Amb aquest objectiu, exposem una pràctica sobre un tema de gran actualitat: les crisis financeres espanyoles entre 1850 i 2014.The goal of this article is twofold. On the one hand, we evaluate the pros and cons of the Information and Communication Technologies (ICTs) in the teaching of economic history. For this, we first describe some of the initiatives launched by the Economic History Group at the Universitat de València. On the other hand, we explain how did we combine distinct teaching approaches to stimulate the student’s motivation, teamwork, and learner autonomy. In doing so, we present a practical exercise on a hotly debated topic: Financial Crises in Spain, 1850-2014.El objetivo de este trabajo es doble. Por un lado, analizar las ventajas y limitaciones de las Tecnologías de la Información y Comunicación (TICs) en la enseñanza de la historia económica. Por esta razón, primero describimos algunas de las medidas adoptadas dentro del Área de Historia e Instituciones Económicas de la Universitat de València. Por otro, explicar mediante la exposición de una práctica concreta, cómo hemos tratado de combinar diferentes metodologías para estimular la motivación del alumno, el trabajo grupal, y el estudio autónomo. Para ello, expondremos una práctica sobre un tema de gran actualidad: las crisis financieras españolas entre 1850 y 2014

Allergic rhinitis: continuous or on demand antihistamine therapy?

Allergic rhinitis is an inflammatory disease of the nasal mucosa, caused by an IgE-mediated reaction after exposure to the allergen to which the patient is sensitized. Histamine is the most important preformed mediator released in the early stage of the allergic reaction, and also contributes to the late phase of the latter, exhibiting proinflammatory effects. Minimal persistent inflammation is a physiopathological phenomenon induced by the presence of an inflammatory cell infiltrate, together with ICAM-1 expression in the epithelial cells of the mucosa exposed to the allergen to which they are sensitized, in the absence of clinical symptoms. This molecule is considered to be an allergic inflammatory marker. The priming effect first described by Connell in 1968 consists of the reduction in the allergen concentration required to elicit a nasal hyper-response when performing a daily nasal exposure test. This implies that with natural exposure to inhaled allergens, small amounts of environmental allergen will maintain the patient symptoms, and thus of course minimal persistent inflammation. Considering the above, it is questionable whether antihistamines should be administered on a continuous basis or upon demand. The antihistamines, and fundamentally the second-generation drugs, have been shown to exert an antiinflammatory effect, and this effect is greater when the drug is administered continuously than when administered upon demand. Likewise, a reduction in treatment cost and an improvement in quality of life among patients treated on a continuous basis has been documented. However, no studies have been specifically designed to clarify the indication of treatment on a continuous basis or upon demand, as occurs in the GINA. As a result, the individualization of treatment according to the concrete characteristics of each patient seems to be the best approach, at least for the time being

Use of antihistamines in pediatrics

Drugs with antihistamine action are among the most commonly prescribed medicines in pediatrics. According to the International Medical Statistics (IMS), almost two million antihistamine units (in solution) for pediatric use were sold in Spain during 2006 - at a cost of nearly 6 million euros. Of this amount, 34% corresponded to first-generation (or sedating) antihistamines. The difficulties inherent to research for drug development increase considerably when the pediatric age range is involved. The use of any medication in this age group must adhere to the strictest safety criteria, and must offer the maximum guarantees of effi cacy. For this reason, detailed knowledge of the best scientific evidence available in relation to these aspects is essential for warranting drug use. The first-generation antihistamines have never been adequately studied for pediatric age groups, though they are still widely used in application to such patients. In contrast, studies in children have been made with the second-generation antihistamines, allowing us to know their safety profile, and such medicines are available at pediatric dosages that have been well documented from the pharmacological perspective. The present review affords an update to our most recent knowledge on antihistamine use in children, based on the best scientific evidence available

Air pollution and allergens

It is well known that the prevalence of allergic diseases has increased in recent decades in the industrialized world. Exposure to environmental pollutants may partially account for this increased prevalence. In effect, air pollution is a growing public health problem. In Europe, the main source of air pollution due to particles in suspension is represented by motor vehicles--particularly those that use diesel fuel. Diesel exhaust particles (DEPs) are composed of a carbon core upon which high-molecular weight organic chemical components and heavy metals deposit. Over 80% of all DEPs are in the ultrafine particle range (< 0.1 pm in diameter). Air pollutants not only have a direct or indirect effect upon the individual, but also exert important actions upon aeroallergens. Pollen in heavily polluted zones can express a larger amount of proteins described as being allergenic. Through physical contact with the pollen particles, DEPs can disrupt the former, leading to the release of paucimicronic particles and transporting them by air--thus facilitating their penetration of the human airways. Climate change in part gives rise to variations in the temperature pattern characterizing the different seasons of the year. Thus, plants may vary their pollination calendar, advancing and prolonging their pollination period. In addition, in the presence of high CO2 concentrations and temperatures, plants increase their pollen output. Climate change may also lead to the extinction of species, and to the consolidation of non-native species--with the subsequent risk of allergic sensitization among the exposed human population. In conclusion, there is sufficient scientific evidence on the effect of air pollution upon allergens, increasing exposure to the latter, their concentration and/or biological allergenic activity

Effect of pollutants upon patients with respiratory allergies

Epidemiological studies have revealed an association between pollution and allergic respiratory diseases. The main pollutants in this sense are nitric oxide, ozone, and particulate matter. The present review on one hand addresses the chemical characteristics of each of these three groups of pollutants and their main sources, and on the other examines their effects upon allergic respiratory diseases--placing special emphasis on the effects of diesel exhaust particles. For each of the pollutants, the underlying mechanisms capable of influencing allergic respiratory diseases are commented. Lastly, an evaluation is made of some of the genetic aspects related to the response to pollutants