Variables in Globular Cluster NGC 5024

We present the results of a commissioning campaign to observe Galactic globular clusters for the search of microlensing events. The central 10' X 10' region of the globular cluster NGC 5024 was monitored using the 2-m Himalayan Chandra Telescope in R-band for a period of about 8 hours on 24 March 2010. Light curves were obtained for nearly 10,000 stars, using a modified Difference Image Analysis (DIA) technique. We identified all known variables within our field of view and revised periods and status of some previously reported short-period variables. We report about eighty new variable sources and present their equatorial coordinates, periods, light curves and possible types. Out of these, 16 are SX Phe stars, 10 are W UMa-type stars, 14 are probable RR Lyrae stars and 2 are detached eclipsing binaries. Nine of the newly discovered SX Phe stars and two eclipsing binaries belong to the Blue Straggler Star (BSS) population.Comment: 29 pages, 22 figures, replaced with rewritten data reduction par

Las combinaciones fijas en hipertensión: análisis de impacto presupuestario para el Sistema Nacional de Salud Español de la comercialización de la combinación fija de olmesartan/amlodipino

ResumenObjetivoRealizar un análisis de impacto presupuestario (AIP) de la introducción en el Sistema Nacional de Salud (SNS) de la combinación fija (CF) de olmesartan/amlodipino (20/5, 40/5 y 40/10mg) en la indicación aprobada.DiseñoModelo de árbol de decisión que refleja el algoritmo de tratamiento más habitual en la práctica clínica de la hipertensión junto con sus probabilidades de ocurrencia.EmplazamientoPerspectiva del SNS para un período de 3 años (2010-2012).ParticipantesPoblación española hipertensa mayor de 35 años.IntervencionesIntroducción de la CF olmesartan/amlodipino en el mercado español.Mediciones principalesCostes financiados por el SNS (a PVP-IVA) para la población de pacientes susceptibles de ser tratados con la CF frente a los asumidos con la combinación libre (CL) olmesartan y amlodipino.ResultadosLa estimación del gasto farmacéutico con olmesartan y amlodipino en CL era de 25,2 M€ (primer año), 26,4 M€ el segundo año y 27,6 M€ el tercero, totalizando 79,2 M€. Según el modelo, la población susceptible de ser tratada con la CF es de 71.283 pacientes (primer año), con una tasa de crecimiento cercana al 4,8% en los sucesivos años, lo que supone un coste anual de 21,2 M€ (2010), 21,8 M€ (2011) y 22,4 M€ (2012), totalizando 65,4 M€. El AIP muestra un ahorro de 13,8 M€, siendo unos resultados robustos confirmados por los análisis de sensibilidad univariantes de tipo umbral.ConclusiónEl AIP de la CF de olmesartan/amlodipino podría generar unos ahorros netos para el SNS en 3 años de 13,8 M€.AbstractObjectiveTo carry out a budget impact analysis (BIA) of olmesartan/amlodipine (20/5, 40/5 and 40/10mg) marketed as a fixed combination (FC) in its approved indication for the National Health System (NHS).DesigWe developed a decision tree model in order to estimate usual hypertension treatment algorithm in Spanish clinical practice.SettingsThe BIA has been developed from the perspective of the NHS for a period of 3 years (years 2010-2012).ParticipantsSpanish hypertensive population ≥ 35 years old.InterventionsIntroduction into the market of a fixed combination (FC) olmesartan/amlodipine in Spain.Primary measuresExpected costs to be assumed by the Spanish NHS (RRP-VAT) for hypertensive population able to be treated with the FC versus currently assumed costs by the NHS with free combination olmesartan and amlodipine.ResultsEstimated pharmaceutical costs in hypertensive population treated with olmesartan and amlodipine (2 pills) would be €25.2M (1st year), €26.4M (2011), €27.6M (2012), with a total 3-year period of €79.2M. According to patient tree model, the population able to be treated with FC would be 71,283 patients (2010), with a growth rate of 4.8% in the successive years, which supposes an annual cost of €21.2M (2010), €21.8M (2011) and €22.4M (2012), with a total 3-year period of €65.4M. The BIA shows savings of €13.8M in a total 3-year period.ConclusionThe BIA of FC olmesartan/amlodipine could generate net savings of €13.8M for the NHS in the period ranging from years 2010 to 2012

Interaction of Hydrogen with Graphitic Surfaces, Clean and Doped with Metal Clusters

Producción CientíficaHydrogen is viewed as a possible alternative to the fossil fuels in transportation. The technology of fuel-cell engines is fully developed, and the outstanding remaining problem is the storage of hydrogen in the vehicle. Porous materials, in which hydrogen is adsorbed on the pore walls, and in particular nanoporous carbons, have been investigated as potential onboard containers. Furthermore, metallic nanoparticles embedded in porous carbons catalyze the dissociation of hydrogen in the anode of the fuel cells. For these reasons the interaction of hydrogen with the surfaces of carbon materials is a topic of high technological interest. Computational modeling and the density functional formalism (DFT) are helping in the task of discovering the basic mechanisms of the interaction of hydrogen with clean and doped carbon surfaces. Planar and curved graphene provide good models for the walls of porous carbons. We first review work on the interaction of molecular and atomic hydrogen with graphene and graphene nanoribbons, and next we address the effects due to the presence of metal clusters on the surface because of the evidence of their role in enhancing hydrogen storage.Ministerio de Economía, Industria y Competitividad (Grant MAT2014-54378-R

Perfusion-weighted software written in Python for DSC-MRI analysis

IntroductionDynamic susceptibility-weighted contrast-enhanced (DSC) perfusion studies in magnetic resonance imaging (MRI) provide valuable data for studying vascular cerebral pathophysiology in different rodent models of brain diseases (stroke, tumor grading, and neurodegenerative models). The extraction of these hemodynamic parameters via DSC-MRI is based on tracer kinetic modeling, which can be solved using deconvolution-based methods, among others. Most of the post-processing software used in preclinical studies is home-built and custom-designed. Its use being, in most cases, limited to the institution responsible for the development. In this study, we designed a tool that performs the hemodynamic quantification process quickly and in a reliable way for research purposes.MethodsThe DSC-MRI quantification tool, developed as a Python project, performs the basic mathematical steps to generate the parametric maps: cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), signal recovery (SR), and percentage signal recovery (PSR). For the validation process, a data set composed of MRI rat brain scans was evaluated: i) healthy animals, ii) temporal blood–brain barrier (BBB) dysfunction, iii) cerebral chronic hypoperfusion (CCH), iv) ischemic stroke, and v) glioblastoma multiforme (GBM) models. The resulting perfusion parameters were then compared with data retrieved from the literature.ResultsA total of 30 animals were evaluated with our DSC-MRI quantification tool. In all the models, the hemodynamic parameters reported from the literature are reproduced and they are in the same range as our results. The Bland–Altman plot used to describe the agreement between our perfusion quantitative analyses and literature data regarding healthy rats, stroke, and GBM models, determined that the agreement for CBV and MTT is higher than for CBF.ConclusionAn open-source, Python-based DSC post-processing software package that performs key quantitative perfusion parameters has been developed. Regarding the different animal models used, the results obtained are consistent and in good agreement with the physiological patterns and values reported in the literature. Our development has been built in a modular framework to allow code customization or the addition of alternative algorithms not yet implemented

Ecología reproductiva y pesquerías en el contexto iberoamericano

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