Adaptive Langevin Sampler for Separation of t-Distribution Modelled Astrophysical Maps

We propose to model the image differentials of astrophysical source maps by Student's t-distribution and to use them in the Bayesian source separation method as priors. We introduce an efficient Markov Chain Monte Carlo (MCMC) sampling scheme to unmix the astrophysical sources and describe the derivation details. In this scheme, we use the Langevin stochastic equation for transitions, which enables parallel drawing of random samples from the posterior, and reduces the computation time significantly (by two orders of magnitude). In addition, Student's t-distribution parameters are updated throughout the iterations. The results on astrophysical source separation are assessed with two performance criteria defined in the pixel and the frequency domains.Comment: 12 pages, 6 figure

Overview of key thermal–hydraulic phenomena in severe accident unfolding: Current knowledge and further needs

Severe Accidents (SA) developments are closely and deeply linked with thermal-hydraulics, that is, fluid flow combined with heat and mass transfer. The present paper synthesizes this relation during an accident unfolding and provides an overview of the remaining gaps associated to thermal-hydraulics that need to be addressed to reduce the uncertainties associated to SA and to optimize their management. Some of those thermal–hydraulic phenomena are common to other areas, but most of them are genuine to the SA domain. In addition to thermal–hydraulic phenomena affecting SA development, there are others major SA consequences, like fission product transport and eventual release to the environment, that are heavily affected by thermal–hydraulic boundary conditions and need to be investigated under the anticipated accident conditions. There is a consensus that any investigation to be launched in the coming years should have a direct impact on either reducing the uncertainties associated to their modelling or on optimizing their management, or on both; such consensus was soundly built in the EC EURSAFE project and has been renewed under the frame of the SARNET projects and the SNETP/NUGENIA/TA2 activities

Towards an optimized management of accidents

Nuclear safety has been one of the main research domains in EURATOM programs for decades, and accident prevention and mitigation have drawn much of the attention paid over the years to this framework. In the essence of this interest are designs of reliable systems, accurate methods to estimate risk, and a permanent search for optimizing accident management. This is the focus of PIACE, MUSA, and AMHYCO projects. A fully passive system for decay heat removal in off-nominal conditions based on the concept of isolation condenser is the subject of PIACE. A harmonized approach for analyzing uncertainties and sensitivities associated with severe accidents, particularly with the source term to the environment, is the final aim of MUSA. And finally, AMHYCO is exploring the potential for enhancing the management of combustible gas risk. Despite the project’s diversity, they all will converge on the same outcome: an optimization of nuclear safety from better safety systems, risk estimating methods, and in-accident guidelines. These projects have received funding from the H2020 EURATOM research and training program under grant agreements 847715 (PIACE), 847441 (MUSA), and 945057 (AMHYCO)

Optimización del fresado de piezas de rigidez reducida mediante un modelo de estabilidad tridimensional

El fresado de alta velocidad ha permitido la producción de componentes estructurales aeronáuticos de aluminio a partir de un bloque de partida, obteniendo las conocidas piezas monolíticas. Este proceso es más productivo respecto al ensamblaje de varias piezas para constituir una mediante remaches, debido en parte, a los grandes caudales de viruta que se consiguen. Sin embargo, la agresividad de las condiciones de corte trae pareja una serie de problemas, siendo unos de los más importantes las vibraciones autoexcitadas conocidas como chatter regenerativo, que pueden producir la rotura o desgaste prematuro del husillo en cortes de desbaste o la aparición de marcas y roturas en la pieza durante el acabado. En este trabajo se presenta un modelo de estabilidad tridimensional que considera la flexibilidad dinámica del conjunto husillo-herramienta y de la pieza para la obtención de diagramas de lóbulos, permitiendo una mejor planificación del mecanizado

Draft genome sequence of the bacteriocinogenic strain Enterococcus faecalis DBH18, isolated from mallard ducks (Anas platyrhynchos)

Here, we report the draft genome sequence of Enterococcus faecalis DBH18, a bacteriocinogenic lactic acid bacterium (LAB) isolated from mallard ducks (Anas platyrhynchos). The assembly contains 2,836,724 bp, with a G+C content of 37.6%. The genome is predicted to contain 2,654 coding DNA sequences (CDSs) and 50 RNAs

Geotraverse south (B-1) : (excursion guidebook. Day 1)

The purpose of this excursion is to make a quick geological reconnaissance of the main stratigraphic and tectonic characteristics of the terranes in the southern part of the Iberian Peninsula, starting with the Alcudian Terrane (days 1 and 2), Obejo-Valseguillo (day 2), Hornachos (day 2), Valencia de las Torres (day 3), Sierra Albarrana (day 3), Olivenza-Monesterio (days 4 and 5), Barrancos (day 5), Aracena (day 5), Pule do Lobo (day 5), and South Portuguese (day 6), by visiting strategic outcrops where the main points and problems can be discussed

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

Diastereoselective Synthesis of C60/Steroid Conjugates

The design and synthesis of fullerene–steroid hybrids by using Prato’s protocol has afforded new fullerene derivatives endowed with epiandrosterone, an important naturally occurring steroid hormone. Since the formation of the pyrrolidine ring resulting from the 1,3-dipolar cyloaddition reaction takes place with generation of a new stereogenic center on the C2 of the five-membered ring, the reaction proceeds with formation of a diastereomeric mixture [compounds 6 and 7 in 70:30 ratio, 8 and 9 in 26:74 ratio (HPLC)] in which the formation of the major diasteroisomers 6 and 9 is consistent with an electrophilic attack of [60]fullerene on the Re face of the azomethine ylide directed by the steroidic unit. The chiroptical properties of these conjugates reveal typical Cotton effects in CD spectra that have been used to assign the absolute configuration of the new fulleropyrrolidines. The electrochemical study of the new compounds reveals the presence of four quasi-reversible reduction waves which are cathodically shifted in comparison with the parent C60, thus ascertaining the proposed structures.Financial support by the Ministerio de Ciencia e Innovación (MINECO) of Spain (CTQ2011-24652, CTQ2011-27253, PIB2010JP-00196, and CSD2007-00010 projects) and CAM (Madrisolar-2) is acknowledged; A.R. thanks UCM for financial support; M.S. is indebted to Programa del Grupo Santander 2012