The chemical composition of carbon stars: The R-type stars

The aim of this work is to shed some light on the problem of the formation of carbon stars of R-type from a detailed study of their chemical composition. We use high-resolution and high signal-to-noise optical spectra of 23 R-type stars selected from the Hipparcos catalogue. The chemical analysis is made using spectral synthesis in LTE and state-of-the-art carbon-rich spherical model atmospheres. We derive their CNO content (including the carbon isotopic ratio), average metallicity, lithium, and light (Sr, Y, Zr) and heavy (Ba, La, Nd, Sm) s-element abundances. The observed properties of the stars (galactic distribution, kinematics, binarity, photometry and luminosity) are also discussed. Our analysis shows that late-R stars are carbon stars with identical chemical and observational characteristics than the normal (N-type) AGB carbon stars. We confirm the results of the sole previous abundance analysis of early-R stars by Dominy (1984, ApJS, 55, 27), namely: they are carbon stars with near solar metallicity showing enhanced nitrogen, low carbon isotopic ratios and no s-element enhancements. In addition, we have found that early-R stars have Li abundances larger than expected for post RGB tip giants. We also find that a significant number (aprox. 40 %) of the early-R stars in our sample are wrongly classified, being probably classical CH stars and normal K giants. In consequence, we suggest that the number of true R stars is considerably lower than previously believed. We briefly discuss the different scenarios proposed for the formation of early-R stars. The mixing of carbon during an anomalous He-flash is favoured, although no physical mechanism able to trigger that mixing has been found yet. The origin of these stars still remains a mystery.Comment: 15 pages, 8 figures, accepted for publication in Astronomy and Astrophysic

Sellar and Parasellar Imaging

The skull base is a complex anatomical region that harbors many important neurovascular structures in a relatively confined space. The pathology that can develop at this site is varied, and many disease processes may present with similar clinical and neuroimaging findings. While computed tomography maintains a role in the evaluation of many entities and can, for instance, delineate osseous erosion with great detail and characterize calcified tumor matrices, magnetic resonance imaging (MRI) is the mainstay in the neuroimaging assessment of most pathology occurring at the skull base. Various MRI sequences have proven to be robust tools for tissue characterization and can provide information on the presence of lipids, paramagnetic and diamagnetic elements, and tumor cellularity, among others. In addition, currently available MRI techniques are able to generate high spatial resolution images that allow visualization of cranial nerves and their involvement by adjacent pathology. The information obtained from such examinations may aid in the distinction of these disease processes and in the accurate delineation of their extent prior to biopsy or treatment planning

Determinants of the outcomes of services outsourcing: an empirical study of transport services.

The purpose of our study is to examine whether the design and management of the interfaces and interaction processes between customer and provider in services outsourcing are determinants of the results achieved by the outsourcing company. Following the conceptual framework initiated in the study by Wynstra et al. [11], this study focuses on transport services and hypothesized relationships are tested using the Partial Least Squares (PLS) statistical technique. The primary data used was obtained from a survey in three different countries (Germany, Japan and Spain), and from manufacturing companies in the electronics, automotive and machinery sectors. Among other things, the results show that both the structural dimensions of interaction (the organization's resources that it must commit) and the process dimensions of interaction (that consider the dynamic nature of the relationships), are important for obtaining adequate performance from transport services outsourcing.Spanish National Program of Industrial Design and Production DPI 2009 11148PAIDI Excellence Projects P08-SEJ0384

Population studies of arthropods on Melia azedarach in Seville (Spain), with special reference to Eutetranychus orientalis (Acari: Tetranychidae) and its natural enemies

Eutetranychus orientalis has become an important pest of the ornamental tree Melia 8 azedarach in the city of Seville (Spain). Trees suffer total defoliation at the end of summer. 9 Studies were conducted in a regular plantation of this tree in the Miraflores Park in 2008 and 10 2009, to determine the arthropod faunal composition, with particular interest in the possible 11 natural enemies of E. orientalis. Eutetranychus orientalis accounted for 98.3% of the 12 arthropods found on the leaflets. Two species of phytoseiids were found, Euseius scutalis and 13 Euseius stipulatus, but they only represented 0.2% of the arthropods. The most abundant 14 insect was the predator thrips Scolothrips longicornis, which accounted for 0.9% of the 15 arthropods found. The population of E. orientalis reached two peaks in 2008, with 325 16 individuals per leaflet in August, and 100 individuals per leaflet in November. Scolothrips 17 longicornis densities closely followed E. orientalis, and predation was observed on various 18 mite instars. Phytoseiids did not show such a response to the E. orientalis densities. 19 Eutetranychus orientalis was more abundant in the exterior part of the plantation. No 20 differences of arthropod densities were found between the various orientations in the 21 plantation (north vs. south, east vs. west), although E. orientalis densities were different 22 between rows. Distribution of E. orientalis population was highly aggregative, that of S. 23 longicornis population was less aggregative, whereas the phytoseiid population showed a 24 random distribution

Methodology for assessing electric vehicle charging infrastructure business models

The analysis of economic implications of innovative business models in networked environments, as electro-mobility is, requires a global approach to ensure that all the involved actors obtain a benefit. Although electric vehicles (EVs) provide benefits for the society as a whole, there are a number of hurdles for their widespread adoption, mainly the high investment cost for the EV and for the infrastructure. Therefore, a sound business model must be built up for charging service operators, which allows them to recover their costs while, at the same time, offer EV users a charging price which makes electro-mobility comparable to internal combustion engine vehicles. For that purpose, three scenarios are defined, which present different EV charging alternatives, in terms of charging power and charging station ownership and accessibility. A case study is presented for each scenario and the required charging station usage to have a profitable business model is calculated. We demonstrate that private home charging is likely to be the preferred option for EV users who can charge at home, as it offers a lower total cost of ownership under certain conditions, even today. On the contrary, finding a profitable business case for fast charging requires more intensive infrastructure usage.European Commission's FP

Psicopatología asociada al consumo de cocaína y alcohol

Cada vez resulta más frecuente encontrar en la clínica trastornos psiquiátricos asociados al consumo de drogas. Además, la evolución de la realidad asistencial no deja lugar a dudas: lo que hace unos años era una prospección de futuro que a todos nos preocupaba hoy se ha convertido y con todas las consecuencias en el día a día. La comorbilidad psiquiátrica es más frecuente en adictos que en la población general.El consumo de alcohol por parte de los cocainómanos, y viceversa, es muy frecuente lo cual supone un riesgo aún mayor para la salud y un aumento de la comorbilidad psiquiátrica. De los datos epidemiológicos y toxicológicos, se ha sugerido que la combinación de alcohol y cocaína produce una toxicidad aumentada además de cambios conductuales.El presente trabajo consta de 2 bloques fundamentalmente, una referida a la clínica y psicopatología del consumo del alcohol y la cocaína, (Aunque son bastante bien conocidos los trastornos psíquicos asociados al alcoholismo puro, resultan menos conocidos los por ejemplo- derivados de un alcoholismo secundario o sobreañadido al consumo de otras sustancias), y la otra a su abordaje terapéutico desde diversos frentes

Unprecedented layered coordination polymers of dithiolene group 10 metals: Magnetic and electrical properties

One-pot reactions between Ni(ii), Pd(ii) or Pt(ii) salts and 3,6-dichloro-1,2-benzenedithiol (HSC6H2Cl2SH) in KOH medium under argon lead to a series of bis-dithiolene coordination polymers. X-ray analysis shows the presence of a common square planar complex [M(SC6H2Cl2S)2]2- linked to potassium cations forming either a two-dimensional coordination polymer network for {[K2(μ-H2O)2(μ-thf)(thf)2][M(SC6H2Cl2S)2]}n [M = Ni (1) and Pd (2)] or a one-dimensional coordination polymer for {[K2(μ-H2O)2(thf)6][Pt(SC6H2Cl2S)2]}n (3). In 3 the coordination environment of the potassium ions may slightly change leading to the two-dimensional coordination polymer {[K2(μ-H2O)(μ-thf)2][Pt(SC6H2Cl2S)2]}n (4) that crystallizes together with 3. The physical characterization of compounds 1-3 show similar trends, they are diamagnetic and behave as semiconductorsWe thank financial support from MICINN (MAT2013-46753-C2-1-P, CTQ2014-52758-P and MAT2014-56143-R) and Generalitat Valenciana (PrometeoII/2014/076

The Dual Role of Platelets in the Cardiovascular Risk of Chronic Inflammation

Patients with chronic inflammatory diseases often exhibit cardiovascular risk. This risk is associated with the systemic inflammation that persists in these patients, causing a sustained endothelial activation. Different mechanisms have been considered responsible for this systemic inflammation, among which activated platelets have been regarded as a major player. However, in recent years, the role of platelets has become controversial. Not only can this subcellular component release pro- and anti-inflammatory mediators, but it can also bind to different subsets of circulating lymphocytes, monocytes and neutrophils modulating their function in either direction. How platelets exert this dual role is not yet fully understood