A possible black hole in the gamma-ray microquasar LS 5039

The population of high energy and very high energy gamma-ray sources, detected with EGRET and the new generation of ground-based Cherenkov telescopes, conforms a reduced but physically important sample. Most of these sources are extragalactic (e.g., blazars), while among the galactic ones there are pulsars and SN remnants. The microquasar LS 5039, previously proposed to be associated with an EGRET source by Paredes et al. (2000), has recently been detected at TeV energies, confirming that microquasars should be regarded as a class of high energy gamma-ray sources. To model and understand how the energetic photons are produced and escape from LS 5039 it is crucial to unveil the nature of the compact object, which remains unknown. Here we present new intermediate-dispersion spectroscopy of this source which, combined with values reported in the literature, provides an orbital period of 3.90603+/-0.00017 d, a mass function f(M)=0.0053+/-0.0009 M_sun, and an eccentricity e=0.35+/-0.04. Atmosphere model fitting to the spectrum of the optical companion, together with our new distance estimate of d=2.5+/-0.1 kpc, yields R_opt=9.3+0.7-0.6 R_sun, log (L_opt/L_sun)=5.26+/-0.06, and M_opt=22.9+3.4-2.9 M_sun. These, combined with our dynamical solution and the assumption of pseudo-synchronization, yield an inclination i=24.9+/-2.8 degree and a compact object mass M_X=3.7+1.3-1.0 M_sun. This is above neutron star masses for most of the standard equations of state and, therefore, we propose that the compact object in LS 5039 is a black hole. We finally discuss about the implications of our orbital solution and new parameters of the binary system on the CNO products, the accretion/ejection energetic balance, the SN explosion scenario, and the behaviour of the TeV emission with the new orbital period.Comment: 10 pages, 8 figures. Accepted for publication in MNRAS. Minor changes according to referee repor

RT-MOVICAB-IDS: Addressing real-time intrusion detection

This study presents a novel Hybrid Intelligent Intrusion Detection System (IDS) known as RT-MOVICAB-IDS that incorporates temporal control. One of its main goals is to facilitate real-time Intrusion Detection, as accurate and swift responses are crucial in this field, especially if automatic abortion mechanisms are running. The formulation of this hybrid IDS combines Artificial Neural Networks (ANN) and Case-Based Reasoning (CBR) within a Multi-Agent System (MAS) to detect intrusions in dynamic computer networks. Temporal restrictions are imposed on this IDS, in order to perform real/execution time processing and assure system response predictability. Therefore, a dynamic real-time multi-agent architecture for IDS is proposed in this study, allowing the addition of predictable agents (both reactive and deliberative). In particular, two of the deliberative agents deployed in this system incorporate temporal-bounded CBR. This upgraded CBR is based on an anytime approximation, which allows the adaptation of this Artificial Intelligence paradigm to real-time requirements. Experimental results using real data sets are presented which validate the performance of this novel hybrid IDSMinisterio de Economía y Competitividad (TIN2010-21272-C02-01, TIN2009-13839-C03-01), Ministerio de Ciencia e Innovación (CIT-020000-2008-2, CIT-020000-2009-12

Hot Settling Accretion Flow onto a Spinning Black Hole

We study the structure and properties of hot MHD accretion onto a Kerr black hole. In such a system, the hole is magnetically coupled to the inflowing gas and exerts a torque onto the accretion flow. A hot settling flow can form around the hole and transport the angular momentum outward, to the outer edge of the flow. Unlike other hot flows, such as advection- and convection-dominated flows and inflow-outflow solutions (ADAFs, CDAFs, and ADIOS), the properties of the hot settling flow are determined by the spin of the central black hole, but are insensitive to the mass accretion rate. Therefore, it may be possible to identify rapidly spinning BHs simply from their broad-band spectra. Observationally, the hot settling flow around a Kerr hole is somewhat similar to other hot flows in that they all have hard, power-law spectra and relatively low luminosities. Thus, most black hole candidates in the low/hard and, perhaps, intermediate X-ray state may potentially accrete via the hot settling flow. However, a settling flow will be somewhat more luminous than ADAFs/CDAFs/ADIOS, will exhibit high variability in X-rays, and may have relativistic jets. This suggests that galactic microquasars and active galactic nuclei may be powered by hot settling flows. We identify several galactic X-ray sources as the best candidates.Comment: 7 pages, 1 figure. Submitted to Ap

Anatomical Study of the Canine Limbs in Relation to External Skeletal Fixation: Introduction and Delimitation of Safe, Hazardous and Unsafe Corridors

An anatomical study of the canine limbs was carried out in order to identify, locate and measure the extent of the safe, hazardous and unsafe corridors for pin insertion for the use of external skeletal fixation. Topographical dissections and cross-sections of fresh anatomical specimens of canine limbs were used to localise important neurovascular structures and musculotendinous units and to measure the extent of the corridors. Safe corridors for external skeletal fixator pin insertion are clearly present in the eccentric bones of the canine lower limbs. Although no clear safe passages were identified in concentric bones of the upper limb, hazardous areas and lines are described as the safest for application of external fixation frames. The feasibility of the application of different fixator configurations through safe areas in the canine appendicular long bones is discussed. Some guidelines are given in order to allow the orthopaedic surgeon to follow sound anatomical principles of fixator application and to reduce the incidence of some avoidable complications

Anisotropic pure-phase plates for quality improvement of partially coherent, partially polarized beams

From a theoretical point of view, the use of anisotropic pure-phase plates (APP) is considered in order to improve the quality parameter of certain partially coherent, partially polarized beams. It is shown that, to optimize the beam-quality parameter, the phases of the two Cartesian components of the field at the output of the APP plate should, be identical and should exhibit a quadratic dependence on the radial polar coordinate

Deadline Prediction Scheduling based on Benefits

This paper describes a scheduling algorithm that composes a scheduling plan which is able to predict the completion time of the arriving tasks. This is done by performing CPU booking. This prediction is used to establish a temporal commitment with the client that invokes the execution of the task. This kind of scheduler is very useful in scenarios where Service-Oriented Computing is deployed and the execution time is used as a parameter for QoS. This scheduler is part of an architecture that is based on the Distributed Goal-Oriented Computing paradigm, which allows agents to express their own goals and to reach them by means of service compositions. Moreover, the scheduler is also able to prioritize those tasks which provide greater benefits to the OS. In this work, the scheduler has been designed in several iterations and tested by means of a set of experiments that compare the scheduler algorithm with a representative set of scheduling algorithms. © 2012 Elsevier B.V. All rights reserved.This work is supported by the TIN2009-13839-C03-01 project of the Spanish government, PROMETEO/2008/051 project, FEDER funds and CONSOLIDER-INGENIO 2010 under grant CSD2007-00022.Palanca Cámara, J.; Navarro Llácer, M.; García-Fornes, A.; Julian Inglada, VJ. (2013). Deadline Prediction Scheduling based on Benefits. Future Generation Computer Systems. 29(1):61-73. https://doi.org/10.1016/j.future.2012.05.007S617329

Risk factors of lung, head and neck, esophageal, and kidney and urinary tract carcinomas after liver transplantation: the effect of smoking withdrawal

Liver transplant recipients have an increased risk of malignancy. Smoking is related to some of the most frequent causes of posttransplant malignancy. The incidence and risk factors for the development of neoplasia related to smoking (head and neck, lung, esophageal, and kidney and urinary tract carcinomas) were studied in 339 liver transplant recipients. Risk factors for the development of smoking-related neoplasia were also studied in 135 patients who had a history of smoking so that it could be determined whether smoking withdrawal was associated with a lower risk of malignancy. After a mean follow-up of 7.5 years, 26 patients were diagnosed with 29 smoking-related malignancies. The 5- and 10-year actuarial rates were 5% and 13%, respectively. In multivariate analysis, smoking and older age were independently associated with a higher risk of malignancy. In the smoker subgroup, the variables related to a higher risk of malignancy were active smoking and older age. In conclusion, smoking withdrawal after liver transplantation may have a protective effect against the development of neoplasia

Calibration of ALMA as a phased array: ALMA observations during the 2017 VLBI campaign

We present a detailed description of the special procedures for calibration and quality assurance of Atacama Large Millimeter/submillimeter Array (ALMA) observations in Very Long Baseline Interferometry (VLBI) mode. These procedures are required to turn the phased ALMA array into a fully calibrated VLBI station. As an illustration of these methodologies, we present full-polarization observations carried out with ALMA as a phased array at 3mm (Band 3) and 1.3mm (Band 6) as part of Cycle-4. These are the first VLBI science observations conducted with ALMA and were obtained during a 2017 VLBI campaign in concert with other telescopes worldwide as part of the Global mm-VLBI Array (GMVA, April 1-3) and the Event Horizon Telescope (EHT, April 5-11) in ALMA Bands 3 and 6, respectively.Comment: 39 pages, 20 figures, 10 tables, accepted by PAS

Surface phase transitions in BiFeO3 below room temperature

We combine a wide variety of experimental techniques to analyze two heretofore mysterious phase transitions in multiferroic bismuth ferrite at low temperature. Raman spectroscopy, resonant ultrasound spectroscopy, EPR, X-ray lattice constant measurements, conductivity and dielectric response, specific heat and pyroelectric data have been collected for two different types of samples: single crystals and, in order to maximize surface/volume ratio to enhance surface phase transition effects, BiFeO3 nanotubes were also studied. The transition at T=140.3K is shown to be a surface phase transition, with an associated sharp change in lattice parameter and charge density at the surface. Meanwhile, the 201K anomaly appears to signal the onset of glassy behaviour

Coherent-mode decomposition of partially polarized, partially coherent sources

It is shown that any partially polarized, partially coherent source can be expressed in terms of a suitable superposition of transverse coherent modes with orthogonal polarization states. Such modes are determined through the solution of a system of two coupled integral equations. An example, for which the modal decomposition is obtained in closed form in terms of fully linearly polarized Hermite Gaussian modes, is given