Orbital X-Ray Variability of the Microquasar LS 5039

The properties of the orbit and the donor star in the high mass X-ray binary microquasar LS 5039 indicate that accretion processes should mainly occur via a radiatively driven wind. In such a scenario, significant X-ray variability would be expected due to the eccentricity of the orbit. The source has been observed at X-rays by several missions, although with a poor coverage that prevents to reach any conclusion about orbital variability. Therefore, we conducted RossiXTE observations of the microquasar system LS 5039 covering a full orbital period of 4 days. Individual observations are well fitted with an absorbed power-law plus a Gaussian at 6.7 keV, to account for iron line emission that is probably a diffuse background feature. In addition, we have taken into account that the continuum is also affected by significant diffuse background contamination. Our results show moderate power-law flux variations on timescales of days, as well as the presence of miniflares on shorter timescales. The new orbital ephemeris of the system recently obtained by Casares et al. have allowed us to show, for the first time, that an increase of emission is seen close to the periastron passage, as expected in an accretion scenario. Moreover, the detected orbital variability is a factor of ~4 smaller than the one expected by using a simple wind accretion model, and we suggest that an accretion disk around the compact object could be responsible for this discrepancy. On the other hand, significant changes in the photon index are also observed clearly anti-correlated with the flux variations. We interpret the overall X-ray spectral characteristics of LS 5039 in the context of X-ray radiation produced by inverse Compton and/or synchrotron processes in the jet of this microquasar.Comment: published in Astrophysical Journal, submission format (real number of pages: 7, 4 figures

Helium abundance difference within globular clusters: NGC 2808

Multiple populations have been recently detected in most Galactic globular clusters, even with no significant spread in metallicity. Unusual features of the observed colourmagnitude diagrams can be explained by differences in the He content of the stars belonging to the sub-populations. We report on empirical evidence of He abundance spread in a few globular clusters, with particular attention to NGC 2808, where He abundance variation has been measured in a pair of otherwise identical red giant stars using the HeI 1083 nm line.A quantitative estimate of this difference has been derived by appropriate chromospheric modelling, in very good agreement with stellar evolution requirements.Fil: Cacciari, C.. INAF, Observatorio Astronomico di Bologna; ItaliaFil: Pasquini, L.. ESO; AlemaniaFil: Valenti, E.. ESO; AlemaniaFil: Käufl, H. U.. ESO; AlemaniaFil: Mauas, Pablo Jacobo David. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

Leguminosas bioactivas para mejorar el perfil lipídico de la carne de cordero

6 páginas, 2 figuras, 1 tabla.La utilización de leguminosas forrajeras en la dieta de los rumiantes puede ofrecer importantes ventajas. Además de su elevado valor proteico, algunas especies como la esparceta o el trébol rojo, contienen compuestos bioactivos que podrían mejorar la calidad nutricional de la carne. Entre ellos, destacan los taninos en la esparceta y la polifenol oxidasa en el trébol rojo. Ahora bien, la climatología de muchas áreas limita su aprovechamiento en verde. En este estudio, mostramos que la utilización de la esparceta y el trébol rojo conservados mediante ensilado podría ser una buena alternativa para la alimentación de corderos, al aumentar la concentración de ácidos grasos poliinsaturados (PUFA) en la carne a través de su efecto sobre el metabolismo lipídico ruminal. Aunque el mecanismo de acción de los compuestos bioactivos presentes en estos forrajes probablemente sea distinto, sus efectos sobre el perfil de ácidos grasos de la carne parecen ser similares y aditivos.Este trabajo forma parte del proyecto Legume Plus, financiado por la Comisión Europea a través de una Red de Formación Inicial Marie Curie (PITN GA- 2011- 289377) PG . Toral disfruta de un contrato Ramón y Cajal, financiado por el Ministerio de Economía, lndustria y Competitividad.Peer reviewe

Cirugía laparoscópica hepática y pancreática

The development of laparoscopic surgery also includes the more complex procedures of abdominal surgery such as those that affect the liver and the pancreas. From diagnostic laparoscopy, accompanied by laparoscopic echography, to major hepatic or pancreatic resections, the laparoscopic approach has spread and today encompasses practically all of the surgical procedures in hepatopancreatic pathology. Without forgetting that the aim of minimally invasive surgery is not a better aesthetic result but the reduction of postoperative complications, it is undeniable that the laparoscopic approach has brought great benefits for the patient in every type of surgery except, for the time being, in the case of big resections such as left or right hepatectomy or resections of segments VII and VIII. Pancreatic surgery has undergone a great development with laparoscopy, especially in the field of distal pancreatectomy due to cystic and neuroendocrine tumours where the approach of choice is laparoscopic. Laparoscopy similarly plays an important role, together with echolaparoscopy, in staging pancreatic tumours, prior to open surgery or for indicating suitable treatment. In coming years, it is to be hoped that it will continue to undergo an exponential development and, together with the advances in robotics, it will be possible to witness a greater impact of the laparoscopic approach on the field of hepatic and pancreatic surgery

Portal Revascularization in the Setting of Cavernous Transformation Through a Paracholedocal Vein: A Case Report

Diffuse thrombosis of the entire portal system (PVT) and cavernomatous transformation of the portal vein (CTPV) represents a demanding challenge in liver transplantation. We present the case of a patient with nodular regenerative hyperplasia and recurrent episodes of type B hepatic encephalopathy concomitant with PVT as well as CTPV, successfully treated with orthotopic liver transplantation. The portal inflow to the graft was carried out through the confluence of 2 thin paracholedochal varicose veins, obtaining good early graft function and recovery of the encephalopatic episodes. This alternative should be kept in mind as an option to assure hepatopetal splanchnic flow in those cases of diffuse thrombosis and cavernomatous transformation of portal vein. CI - Copyright (c) 2010 Elsevier Inc. All rights reserved

Cirugía bariátrica laparoscópica: bypass gástrico proximal

The spectacular increase in the prevalence of obesity in our society and the significant complications and comorbidities that it gives rise to have stimulated the interest of scientists and public in this pathology. Surgical treatment is at present the only efficient and lasting treatment for morbid obesity and in many cases it appreciably improves, and even definitively cures, associated complications such as the case of diabetes or hypertension. Amongst the different techniques of bariatric surgery, the gastric bypass (GBP) seems to be definitively establishing itself, since it offers an excellent balance between loss of weight (>70% of the excess), surgical risk and subsequent quality of life. The possibility of carrying out this technique employing a laparoscopic approach has improved its acceptance by doctors and patients while it has made it possible to reduce morbidity and mortality, length of hospital stay and costs. Proximal GBP is carried on those patients with an BMI 60 Kg/m2 the GBP employed is denominated distal. Between October 2003 and November 2005, our centre performed 55 laparoscopic proximal Roux-en-Y gastric bypasses via laparoscopy. These involved 42 women and 13 males with an average age of 44 years. The average BMI was 43.5 (35-55.8). The average basal weight was 116.15 Kg. There was no peroperative mortality, nor reinterventions. The BMI after 12 months was 28.4. The average basal weight was 74.2 Kg. Laparoscopic Roux-en-Y proximal gastric bypass is a safe and efficient technique for the treatment of morbid obesity

Automatic detection of interictal spikes using data mining models

Abstract A prospective candidate for epilepsy surgery is studied both the ictal and interictal spikes (IS) to determine the localization of the epileptogenic zone. In this work, data mining (DM) classification techniques were utilized to build an automatic detection model. The selected DM algorithms are: Decision Trees (J4.8), and Statistical Bayesian Classifier (naïve model). The main objective was the detection of IS, isolating them from the EEG's base activity. On the other hand, DM has an attractive advantage in such applications, in that the recognition of epileptic discharges does not need a clear definition of spike morphology. Furthermore, previously 'unseen' patterns could be recognized by the DM with proper 'training'. The results obtained showed that the efficacy of the selected DM algorithms is comparable to the current visual analysis used by the experts. Moreover, DM is faster than the time required for the visual analysis of the EEG. So this tool can assist the experts by facilitating the analysis of a patient's information, and reducing the time and effort required in the process

Positive culture in allograft ACL-reconstruction: what to do?

The transmission of disease or infection from the donor to the recipient is always a risk with the use of allografts. We carried out a research study on the behavioural pattern of implanted allografts, which were initially stored in perfect conditions (all cultures being negative) but later presented positive cultures at the implantation stage. Because there is no information available on how to deal with this type of situation, our aim was to set guidelines on the course of action which would be required in such a case. We conducted a retrospective study of 181 patients who underwent an ACL reconstruction using BPTB allografts. All previous bone and blood cultures and tests for hepatitis B and C, syphilis and HIV were negative. An allograft sample was taken for culture in the operating theatre just before its implantation. The results of the cultures were obtained 3-5 days after the operation. We had 24 allografts with positive culture (13.25%) after the implantation with no clinical infection in any of these patients. Positive cultures could be caused by undetected contamination while harvesting, storing or during manipulation before implantation. The lack of clinical signs of infection during the follow-up of our patients may indicate that no specific treatment-other than an antibiotic protocol-would be required when facing a case of positive culture of a graft piece after its implantation

Secuelas tras inyección ilegal de silicona líquida como técnica de aumento mamario: presentación de 2 casos

The use of liquid silicone for breast augmentation was widespread in the 1960s but was abandoned at the end of the decade due to numerous studies describing the development of a large number of local complications, as well as remote migration of small amounts of silicone. The use of liquid silicone also leads to enormous difficulty in the early diagnosis of breast cancer; these patients are precluded from routine screening programs and must undergo exhaustive periodic examinations. Magnetic resonance imaging has become the most effective test for the early detection of breast cancer in these patients. Indications for subcutaneous mastectomy are the presence of local complications, suspicion of a malignant lesion, or the patient’s desire to prevent both these potential problems

Rol de la alineación de la prótesis y las calcificaciones heterotópicas en la artroplastia total de tobillo

Introducción: El objetivo principal fue evaluar la relación entre la formación de calcificaciones heterotópicas y los parámetros de alineación de la prótesis. Materiales y Métodos: La población estaba formada por 31 pacientes. Se evaluaron variables radiográficas de alineación, como ángulos alfa y beta, centro de rotación astragalino y el porcentaje de cobertura posterior de la tibia en el posoperatorio inmediato y a los 2 años. Las variables de evaluación clínica fueron: la escala analógica visual y la escala de la AOFAS, y el cuestionario SF-36 para evaluar la calidad de vida al final del seguimiento. Resultados: La etiología más frecuente de la artrosis fue la postraumática (67,7%). En el posoperatorio inmediato, el ángulo alfa promedio fue de 88,7° (rango 82-92,6; DE ± 2,61); el ángulo beta, de 84,46° (rango 78,62-91,40; DE ± 3,59). La alineación del componente tibial en el plano frontal fue neutra en 25 pacientes (80,6%), en valgo en 6 (19,4%) y en varo (0%). A los 2 años de seguimiento, el 96% tenía calcificaciones heterotópicas. Mejoraron los puntajes en la escala de la AOFAS (preoperatorio/posoperatorio: 31,90/80,94) y en la escala analógica visual (preoperatorio/posoperatorio: 8,7/1,97) (p <0,05). Conclusiones: No se halló una relación entre calcificaciones heterotópicas y peores resultados funcionales ni de dolor, excepto en los parámetros de calidad de vida (SF-36), como el rol físico, la limitación emocional y la percepción de la salud general, que empeoraron a medida que aumentó el grado de calcificaciones alrededor de la prótesis