Sobre la comparación métrica en la poética clasicista

Este artículo analiza la teoría métrica de la época clasicista y muestra cómo puede descubrirse un cierto impulso, aunque carente de método, hacia la comparación. Esto parece una notable excepción en un período en el que los principios son homogéneos y universales.________________________________ This paper analyzes the classicist theory of meter and shows that it can be found a non-methodical impulse towards comparison. This seems a remarkable exception in a period when principles are homogeneous and universal

S-duality and the prepotential in N=2* theories (I): the ADE algebras

The prepotential of N=2* supersymmetric theories with unitary gauge groups in an Omega-background satisfies a modular anomaly equation that can be recursively solved order by order in an expansion for small mass. By requiring that S-duality acts on the prepotential as a Fourier transform we generalise this result to N=2* theories with gauge algebras of the D and E type and show that their prepotentials can be written in terms of quasi-modular forms of SL(2,Z). The results are checked against microscopic multi-instanton calculus based on localization for the A and D series and reproduce the known 1-instanton prepotential of the pure N=2 theories for any gauge group of ADE type. Our results can also be used to obtain the multi-instanton terms in the exceptional theories for which the microscopic instanton calculus and the ADHM construction are not available.Comment: 33 pages, LaTeX2e, added references, version to be published in JHE

Chemical Differentiation toward the Pipe Nebula Starless Cores

We used the new IRAM 30-m FTS backend to perform an unbiased ~15 GHz wide survey at 3 mm toward the Pipe Nebula young diffuse starless cores. We found an unexpectedly rich chemistry. We propose a new observational classification based on the 3 mm molecular line emission normalized by the core visual extinction (Av). Based on this classification, we report a clear differentiation in terms of chemical composition and of line emission properties, which served to define three molecular core groups. The "diffuse" cores, Av<~15, show poor chemistry with mainly simple species (e.g. CS and CCH). The "oxo-sulfurated" cores, Av~15--22, appear to be abundant in species like SO and SO2, but also in HCO, which seem to disappear at higher densities. Finally, the "deuterated" cores, Av>~22, show typical evolved chemistry prior to the onset of the star formation process, with nitrogenated and deuterated species, as well as carbon chain molecules. Based on these categories, one of the "diffuse" cores (Core 47) has the spectral line properties of the "oxo-sulfurated" ones, which suggests that it is a possible failed core.Comment: Accepted for publication in A&A. 5 pages, 2 figure

The Lorentz force between D0 and D6 branes in string and M(atrix) theory

We use different techniques to analyze the system formed by a D0 brane and a D6 brane (with background gauge fields) in relative motion. In particular, using the closed string formalism of boosted boundary states, we show the presence of a term linear in the velocity, corresponding to the Lorentz force experienced by the D0 brane moving in the magnetic background produced by the D6 brane. This term, that was missed in previous analyses of this system, comes entirely from the R-R odd spin structure and is also reproduced by a M(atrix) theory calculation.Comment: 13 pages, plain LaTeX; some clarifying comments and a reference adde

Estudio gonioscópico del ángulo iridocorneal del Perro de Agua Español

Realizamos un estudio gonioscópico de 46 Perros de Agua Español sanos, apreciando un ángulo iridocorneal abierto en todos los cuadrantes. Describimos las diferentes estructuras del ángulo iridocorneal en esta raza: las dos filas de fibras. del ligamento pectinado, la red trabecular uveal con los espacios de Fontana, y las bandas pigmentadas superficial y profunda. El ángulo iridocorneal en el Perro de Agua Español no presenta características peculiares para esta raza. Hemos observado grandes diferencias entre ojos de distintos perros, menores entre los del mismo perro, y escasas entre los distintos cuadrantes del mismo ojo. El grado de pigmentación de las estructuras del ángulo iridocorneal no depende del sexo ni de la edad, sino sólo de la pigmentación de la capa y del iris.In the present work, we have realized a gonioscopic study in 46 Spanish Water's Dogs. We have seen an iridocorneal angle always open in all quadrants and we have noticed different structures of the iridocorneal angie. the two rows of fibres of the pectinate ligament, the uveal trabecular meshwork with the Fontana's spaces and the deep and superficial pigrnent bands. The iridocorneal angle of the Spanish Water's Dog does not exhibit peculiar characteristics for this race. We have observed large differences between eyes of different dogs, lesser differences between the eyes of the same dog, and rares differences between the different quadrants of the same eye. We have found that the degree of pigmentation of the structures of iridocorneal angle does not depend of the age, only of the pigmentation of the coat and iris

Infections and Multiple Sclerosis: From the World to Sardinia, From Sardinia to the World

Multiple Sclerosis (MS) is an inflammatory disease of the central nervous system. Sardinia, an Italian island, is one of the areas with the highest global prevalence of MS. Genetic factors have been widely explored to explain this greater prevalence among some populations; the genetic makeup of the Sardinians appears to make them more likely to develop autoimmune diseases. A strong association between MS and some infections have been reported globally. The most robust evidence indicating the role of infections is MS development concerns the Epstein-Barr virus (EBV). Anti-EBV antibodies in patients once infected by EBV are associated with the development of MS years later. These features have also been noted in Sardinian patients with MS. Many groups have found an increased expression of the Human endogenous retroviruses (HERV) family in patients with MS. A role in pathogenesis, prognosis, and prediction of treatment response has been proposed for HERV. A European multi-centre study has shown that their presence was variable among populations, ranging from 59% to 100% of patients, with higher HERV expression noted in Sardinian patients with MS. The mycobacterium avium subspecies paratuberculosis (MAP) DNA and antibodies against MAP2694 protein were found to be associated with MS in Sardinian patients. More recently, this association has also been reported in Japanese patients with MS. In this study, we analysed the role of infectious factors in Sardinian patients with MS and compared it with the findings reported in other populations