The accretion environment in Vela X-1 during a flaring period using XMM-Newton

We present analysis of 100 ks contiguous XMM-Newton data of the prototypical wind accretor Vela X-1. The observation covered eclipse egress between orbital phases 0.134 and 0.265, during which a giant flare took place, enabling us to study the spectral properties both outside and during the flare. This giant flare with a peak luminosity of 3.92+0.42-0.09 × 1037 erg s-1 allows estimates of the physical parameters of the accreted structure with a mass of ~1021 g. We have been able to model several contributions to the observed spectrum with a phenomenological model formed by three absorbed power laws plus three emission lines. After analysing the variations with orbital phase of the column density of each component, as well as those in the Fe and Ni fluorescence lines, we provide a physical interpretation for each spectral component. Meanwhile, the first two components are two aspects of the principal accretion component from the surface of the neutron star, the third component seems to be the X-ray light echo formed in the stellar wind of the companion.

Probing large-scale wind structures in Vela X–1 using off-states with INTEGRAL

Vela X–1 is the prototype of the class of wind-fed accreting pulsars in high-mass X-ray binaries hosting a supergiant donor. We have analysed in a systematic way 10 years of INTEGRAL data of Vela X–1 (22–50 keV) and we found that when outside the X-ray eclipse, the source undergoes several luminosity drops where the hard X-rays luminosity goes below ∼3 × 1035 erg s−1, becoming undetected by INTEGRAL. These drops in the X-ray flux are usually referred to as ‘off-states’ in the literature. We have investigated the distribution of these off-states along the Vela X–1 ∼ 8.9 d orbit, finding that their orbital occurrence displays an asymmetric distribution, with a higher probability to observe an off-state near the pre-eclipse than during the post-eclipse. This asymmetry can be explained by scattering of hard X-rays in a region of ionized wind, able to reduce the source hard X-ray brightness preferentially near eclipse ingress. We associate this ionized large-scale wind structure with the photoionization wake produced by the interaction of the supergiant wind with the X-ray emission from the neutron star. We emphasize that this observational result could be obtained thanks to the accumulation of a decade of INTEGRAL data, with observations covering the whole orbit several times, allowing us to detect an asymmetric pattern in the orbital distribution of off-states in Vela X–1.

Measuring the stellar wind parameters in IGR J17544-2619 and Vela X-1 constrains the accretion physics in supergiant fast X-ray transient and classical supergiant X-ray binaries

Context. Classical supergiant X-ray binaries (SGXBs) and supergiant fast X-ray transients (SFXTs) are two types of high-mass X-ray binaries (HMXBs) that present similar donors but, at the same time, show very different behavior in the X-rays. The reason for this dichotomy of wind-fed HMXBs is still a matter of debate. Among the several explanations that have been proposed, some of them invoke specific stellar wind properties of the donor stars. Only dedicated empiric analysis of the donors’ stellar wind can provide the required information to accomplish an adequate test of these theories. However, such analyses are scarce. Aims. To close this gap, we perform a comparative analysis of the optical companion in two important systems: IGR J17544-2619 (SFXT) and Vela X-1 (SGXB). We analyze the spectra of each star in detail and derive their stellar and wind properties. As a next step, we compare the wind parameters, giving us an excellent chance of recognizing key differences between donor winds in SFXTs and SGXBs. Methods. We use archival infrared, optical and ultraviolet observations, and analyze them with the non-local thermodynamic equilibrium (NLTE) Potsdam Wolf-Rayet model atmosphere code. We derive the physical properties of the stars and their stellar winds, accounting for the influence of X-rays on the stellar winds. Results. We find that the stellar parameters derived from the analysis generally agree well with the spectral types of the two donors: O9I (IGR J17544-2619) and B0.5Iae (Vela X-1). The distance to the sources have been revised and also agree well with the estimations already available in the literature. In IGR J17544-2619 we are able to narrow the uncertainty to d = 3.0 ± 0.2 kpc. From the stellar radius of the donor and its X-ray behavior, the eccentricity of IGR J17544-2619 is constrained to e< 0.25. The derived chemical abundances point to certain mixing during the lifetime of the donors. An important difference between the stellar winds of the two stars is their terminal velocities (ν∞ = 1500 km s-1 in IGR J17544-2619 and ν∞ = 700 km s-1 in Vela X-1), which have important consequences on the X-ray luminosity of these sources. Conclusions. The donors of IGR J17544-2619 and Vela X-1 have similar spectral types as well as similar parameters that physically characterize them and their spectra. In addition, the orbital parameters of the systems are similar too, with a nearly circular orbit and short orbital period. However, they show moderate differences in their stellar wind velocity and the spin period of their neutron star which has a strong impact on the X-ray luminosity of the sources. This specific combination of wind speed and pulsar spin favors an accretion regime with a persistently high luminosity in Vela X-1, while it favors an inhibiting accretion mechanism in IGR J17544-2619. Our study demonstrates that the relative wind velocity is critical in class determination for the HMXBs hosting a supergiant donor, given that it may shift the accretion mechanism from direct accretion to propeller regimes when combined with other parameters.

Towards a model-driven engineering approach of data mining

Nowadays, data mining is based on low-level specications of the employed techniques typically bounded to a specic analysis platform. Therefore, data mining lacks a modelling architecture that allows analysts to consider it as a truly software-engineering process. Here, we propose a model-driven approach based on (i) a conceptual modelling framework for data mining, and (ii) a set of model transformations to automatically generate both the data under analysis (via data-warehousing technology) and the analysis models for data mining (tailored to a specic platform). Thus, analysts can concentrate on the analysis problem via conceptual data-mining models instead of low-level programming tasks related to the underlying-platform technical details. These tasks are now entrusted to the model-transformations scaffolding.

Integrating the development of data mining and data warehouses via model-driven engineering

Data mining is one of the most important analysis techniques to automatically extract knowledge from large amount of data. Nowadays, data mining is based on low-level specifications of the employed techniques typically bounded to a specific analysis platform. Therefore, data mining lacks a modelling architecture that allows analysts to consider it as a truly software-engineering process. Bearing in mind this situation, we propose a model-driven approach which is based on (i) a conceptual modelling framework for data mining, and (ii) a set of model transformations to automatically generate both the data under analysis (that is deployed via data-warehousing technology) and the analysis models for data mining (tailored to a specific platform). Thus, analysts can concentrate on understanding the analysis problem via conceptual data-mining models instead of wasting efforts on low-level programming tasks related to the underlying-platform technical details. These time consuming tasks are now entrusted to the model-transformations scaffolding. The feasibility of our approach is shown by means of a hypothetical data-mining scenario where a time series analysis is required.

The Goodness of Simultaneous Fits in ISIS

In a previous work, we introduced a tool for analyzing multiple datasets simultaneously, which has been implemented into ISIS. This tool was used to fit many spectra of X-ray binaries. However, the large number of degrees of freedom and individual datasets raise an issue about a good measure for a simultaneous fit quality. We present three ways to check the goodness of these fits: we investigate the goodness of each fit in all datasets, we define a combined goodness exploiting the logical structure of a simultaneous fit, and we stack the fit residuals of all datasets to detect weak features. These tools are applied to all RXTE-spectra from GRO 1008−57, revealing calibration features that are not detected significantly in any single spectrum. Stacking the residuals from the best-fit model for the Vela X-1 and XTE J1859+083 data evidences fluorescent emission lines that would have gone undetected otherwise.

Epithelial Ovarian Cancers and Endometriosis

Aims: To determine the prevalence of endometriosis in epithelial ovarian cancers (EOC) and the association among their histological subtypes and with endometrial carcinoma. Methods: An observational cohort study performed in 192 patients operated on for EOC, 30 women with atypical endometriosis and 17 with p53 positive endometriosis. Data on associated endometriosis and endometrial carcinomas, histological subtypes, tumor stage, clinical and pathological characteristics and survival were analyzed. Results: Twenty cases of EOC (10.4%) had also endometriosis (12.7 in borderline and 9.3% in invasive cases), being a synchronous finding in most cases. Endometriosis associated with serous or mucinous EOC was observed in 2.2 and 2.7% of cases, respectively. However, this association was observed in 50 of endometrioid and 23% of clear cell EOC. Age, parity and tumor stage were lower in endometriosis-associated EOC patients; and all associated cases were type I (Kurman and Shih's classification) and showed better results in survival rate. Endometrial carcinoma was more frequently associated with endometrioid EOC (25%). Conclusions: There is a significant association between endometriosis, including atypical forms, and endometrioid and clear cell carcinomas, but not with other EOC histotypes. The presence of endometriosis in EOC suggests a better prognosis and an intermediate stage within the progression endometriosis-carcinoma.

El mandato constitucional sobre la orientación de las penas privativas de libertad y la nueva prisión permanente revisable

La introducción de la Prisión Permanente Revisable en nuestro ordenamiento jurídico ha abierto el debate sobre la adecuación de la misma a la Constitución Española de 1978. El autor del presente Trabajo Fin de Grado trata de realizar un pronóstico sobre cuál va a ser, a su juicio, el pronunciamiento del Tribunal Constitucional sobre el recurso de inconstitucionalidad interpuesto por la oposición en el Congreso de los Diputados de la legislatura anterior. Para ello realiza un análisis pormenorizado de la doctrina y jurisprudencia del máximo intérprete de la Constitución sobre artículo 25.2, dado que es el principal argumento al que recurren los detractores de la PPR. No obstante, aunque el TC se pronunciará por primera vez sobre esta materia, el Tribunal Europeo de Derechos Humanos ya ha tenido la ocasión de producir jurisprudencia sobre cuáles son los requisitos para que una cadena perpetua, prevista en otros ordenamientos del Derecho Comparado, sea acorde al Convenio Europeo de Derechos Humanos, jurisprudencia que resultará muy útil para acercarnos al análisis que de esta cuestión ha de efectuar el Tribunal Constitucional. Una vez realizado lo anterior, el TFG concluye haciendo un pronóstico sobre el fallo del TC, con argumentos técnicos y jurídicos, a nivel de un aspirante a obtener el Grado en Derecho.

Modelo de negocio para mejorar la competitividad de la cadena productiva del cuy en Lambayeque-Perú

El principal problema que atraviesan los pequeños productores en la región Lambayeque y en su mayoría a nivel nacional es el bajo nivel de competitividad en sus respectivas cadenas productivas, esto se debe a que no cuentan con una adecuada gestión asociativa y empresarial, desconocen técnicas en manejos productivo y presentan deficiente articulación comercial teniendo como efecto directo bajos niveles de calidad de vida. La presente investigación tiene como objetivo principal plantear un modelo de negocio para mejorar la competitividad de la cadena productiva del cuy en una organización cooperativa de productores de cuyes del distrito de Mórrope, identificando los factores que determinan la competitividad, además plasmando los diversos elementos, componentes, estrategias y actividades que se unen para concretar el objetivo principal. Se presentará un diagnóstico inicial de la Cooperativa en estudio, los datos obtenidos son resultado de visitas y talleres con los asociados quienes respondieron a una encuesta y entrevistas, así mismo para el diagnóstico regional de la cadena del cuy se realizó la búsqueda de información primaria y secundaria, reforzado con entrevistas a especialistas del tema a nivel regional. Finalmente se utilizó la herramienta del marco lógico y del lienzo de modelo de negocio “Canvas” para plasmar la propuesta de mejora de la competitividad en beneficio de la cooperativa en estudio y que servirá como base para replicarse en otras organizaciones siendo acompañada de propuestas reales, validadas por especialistas.