Poisson-Hopf limit of quantum algebras

The Poisson-Hopf analogue of an arbitrary quantum algebra U_z(g) is constructed by introducing a one-parameter family of quantizations U_{z,h}(g) depending explicitly on h and by taking the appropriate h -> 0 limit. The q-Poisson analogues of the su(2) algebra are discussed and the novel su_q^P (3) case is introduced. The q-Serre relations are also extended to the Poisson limit. This approach opens the perspective for possible applications of higher rank q-deformed Hopf algebras in semiclassical contexts.Comment: 13 pages, no figure

High resolution spatial distribution for the hexactinellid sponges Asconema setubalense and Pheronema carpenteri in the Central Cantabrian Sea

In the present work we focus on the distribution of two species of sponges. One of these is Asconema setubalense, a sponge found in rocky substrate that was sampled with a photogrammetric vehicle through georeferenced images. The other is Pheronema carpenteri, which inhabits soft bottoms and was sampled by beam trawl. For the spatial distribution modeling of both sponges, the geomorphological variables of depth, slope, broad and fine scale bathymetric position index (BPI), aspect, and types of bottoms were used, all with a resolution of 32 m. Additionally, layers of silicates and currents near the bottom were extracted from Copernicus Marine Environment Monitoring Service (CMEMS), with a resolution of 4 and 9 km, respectively. Due to the low resolution of the layers, it was considered necessary to validate their use by model comparison, where those that included these variables turned out to be more explanatory than the others. The models were developed in a complex continental break of the Central Cantabrian Sea, which comprises several submarine canyons and a seamount (Le Danois Bank). On the one hand, a very high resolution (32 m) spatial distribution model based on A. setubalense presence was developed using the MaxEnt maximum entropy model. On the other, depending on the availability of density data, generalized additive models (GAMs) were developed for P. carpenteri distribution, although in this case the sampler only allowed a maximum resolution of almost 1 Km. For the A. setubalense, the variables that best explained their distribution were ground types and depth, and for P. carpenteri, silicates, slope, northness, and eastward seawater velocity. The final model scores obtained were an AUC of 0.98 for the MaxEnt model, and an R squared of 0.87 for the GAM model.Postprin

HIV seroprevalence and exposure categories among adolescents tested at a sexually transmitted clinic diseases. Madrid, 1986-2000

[ES] Objetivos Describir los cambios en los tipos de exposición y en la prevalencia del VIH en adolescentes que se hicieron la prueba voluntaria entre 1986 y 2000. Métodos Se incluyó a todos los adolescentes de 13 a 19 años que se hicieron por primera vez la prueba del VIH en una clínica de enfermedades de transmisión sexual de Madrid. Se determinaron anticuerpos en suero mediante ELISA y se confirmaron con Western blot. Se analizaron los cambios en los tipos de exposición y en la seroprevalencia del VIH. Resultados De los 1.327 adolescentes analizados (un 52% de mujeres) el 22% eran menores de 18 años. El número de adolescentes analizados anualmente se mantuvo, aunque descendieron los usuarios de drogas por vía parenteral (UDVP) y las parejas de UDVP, y aumentaron las mujeres que ejercen la prostitución. Se diagnosticaron 108 infecciones, el 71% en UDVP. La seroprevalencia fue del 8,1%, alcanzando el 31,3% en UDVP. Descendió desde 18,2% en 1986 al 1,5% en 1995, manteniéndose desde entonces por debajo del 4%. En varias categorías de exposición se observaron descensos, que alcanzaron significación estadística en varones homo/bisexuales y en mujeres que ejercen la prostitución. El análisis de regresión logística evidenció una reducción anual de la seroprevalencia (odds ratio [OR] = 0,87; intervalo de confianza [IC] del 95%: 0,81-0,94) tras ajustar por los cambios en las categorías de exposición. Conclusiones La prevalencia del VIH ha descendido debido a la disminución de nuevos UDVP y de la prevalencia en varias categorías de exposición. Siguen produciéndose conductas de riesgo e infecciones por el VIH en adolescentes. [EN] Objective To describe the time-trend in exposure categories and HIV seroprevalence among adolescents who underwent to voluntary testing in the period 1986-2000. Methods This study covered all adolescents, aged 13 to 19 years, at their first test for HIV in a sexually transmitted disease clinic in Madrid. Gender, age and HIV risk behaviours were collected. HIV diagnosis relies on ELISA test and Western blot confirmation. Time trends in HIV seroprevalence and exposure categories were analysed. Results A total of 1327 adolescents, 52% women and 22% under 18 years, were studied. The annual number of adolescents remained through the time, but injecting drug users (IDU) and IDU partners declined and female sex workers rose. 108 adolescents were diagnosed with HIV infection –71% were IDU–. HIV seroprevalence was 8.1% –31.3% in IDU–. It declined from 18.2% in 1986 to 1.5% in 1995, and after then it held steady under 4%. This decline involved several risk categories and was statistically significant in homo/bisexual men and female sex workers. The logistic regression analysis, adjusting for changes in exposure categories, showed an annual reduction in HIV seroprevalence (OR = 0.87; 95% CI, 0.81- 0.94). Conclusions HIV seroprevalence has decreased due to the fall of new young IDU and the decrease of seroprevalence within several exposure categories. HIV infections and risk behaviours continue happened among adolescents.Este trabajo ha sido financiado por proyectos FIS (99/0195) y FIPSE (3076/99). Ricardo Gómez Lázaro ha sido beneficiario de una beca del Instituto de Salud Carlos III (00/0073).S

Morphobathymetry and formation processes of sediment waves in the Gulf of Valencia continental slope (NW Mediterranean)

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Mapping the habitats of a complex circalittoral rocky shelf in the Cantabrian Sea (south Bay of Biscay)

This work focuses on the study of habitats and communities of a high structural complexity area at different levels and scales. This gives us a better understanding of an area from an ecological point of view and at the same time provides us with tools that will facilitate management measures. It was developed in a complex circalittoral rocky platform of the central Cantabrian Sea (Bay of Biscay). The sampling was carried out using a towed photogrammetric vehicle and a rock dredge, which was used for the identification of the species. The first level of the study was the abiotic characterization of the area and the analysis of the communities. These analysis were developed using the unsupervised k-means classification method. For abiotic characterization we used the variables directly associated with the composition and morphology of the ground, such as backscatter, BPI (Bathymetric Position Index), roughness and slope. Depth was also included to discriminate between the circalittoral and bathyal zones. We obtained 5 different classes, which we related to the ground types observed by photogrammetry. In the analysis of the communities, the cluster was based on the sampling units extracted from the images (~10 m), from which 5 assemblages were obtained, providing information on the most abundant species of each class supplied by the abiotic study. The second level was carried out considering a management approach and was based on the modeling of the area at lower resolution, more suitable for the analysis of the habitat-fisheries interactions. Thus, the main habitat-forming species (HFS) of the entire circalittoral area were used to perform delta models based on GAMs (Generalize Additive Models). Obtaining the predictions of presence/absence and combining it with the predictions of densities, we got the zero inflated values density-based model. As all the identified habitats have vulnerable benthic species of a certain size settled on rocky bottoms, they can all be considered to belong to the designation 1170 reefs of the Habitats Directive

Integración de dispositivos de salud personal en la plataforma de telecuidado para diabetes PERSONA

La plataforma de telecuidado PERSONA se ha desarrollado en el marco del CIBER-BBN y tiene por objetivo soportar el autocuidado diario de pacientes con diabetes tipo 1. La plataforma proporciona acceso a herramientas de soporte a la decisión, de procesado automático de la información, de monitorización de las variables que afectan a la enfermedad y facilita la comunicación entre los agentes involucrados en el cuidado del paciente. La integración de dispositivos médicos interoperables es un requisito principal de la plataforma PERSONA. En este trabajo presentamos las soluciones adoptadas en cuanto a la integración de dispositivos médicos y analizamos las características de los protocolos de comunicación inalámbrica de los dispositivos considerados y los recursos necesarios para la comunicación con dispositivos móviles de telefonía

On the structure of maximal solvable extensions and of Levi extensions of nilpotent algebras

We establish an improved upper estimate on dimension of any solvable algebra s with its nilradical isomorphic to a given nilpotent Lie algebra n. Next we consider Levi decomposable algebras with a given nilradical n and investigate restrictions on possible Levi factors originating from the structure of characteristic ideals of n. We present a new perspective on Turkowski's classification of Levi decomposable algebras up to dimension 9.Comment: 21 pages; major revision - one section added, another erased; author's version of the published pape

Deep-sea benthic habitats modeling and mapping in a NE Atlantic seamount (Galicia Bank)

En prens

Interstellar MHD Turbulence and Star Formation

This chapter reviews the nature of turbulence in the Galactic interstellar medium (ISM) and its connections to the star formation (SF) process. The ISM is turbulent, magnetized, self-gravitating, and is subject to heating and cooling processes that control its thermodynamic behavior. The turbulence in the warm and hot ionized components of the ISM appears to be trans- or subsonic, and thus to behave nearly incompressibly. However, the neutral warm and cold components are highly compressible, as a consequence of both thermal instability in the atomic gas and of moderately-to-strongly supersonic motions in the roughly isothermal cold atomic and molecular components. Within this context, we discuss: i) the production and statistical distribution of turbulent density fluctuations in both isothermal and polytropic media; ii) the nature of the clumps produced by thermal instability, noting that, contrary to classical ideas, they in general accrete mass from their environment; iii) the density-magnetic field correlation (or lack thereof) in turbulent density fluctuations, as a consequence of the superposition of the different wave modes in the turbulent flow; iv) the evolution of the mass-to-magnetic flux ratio (MFR) in density fluctuations as they are built up by dynamic compressions; v) the formation of cold, dense clouds aided by thermal instability; vi) the expectation that star-forming molecular clouds are likely to be undergoing global gravitational contraction, rather than being near equilibrium, and vii) the regulation of the star formation rate (SFR) in such gravitationally contracting clouds by stellar feedback which, rather than keeping the clouds from collapsing, evaporates and diperses them while they collapse.Comment: 43 pages. Invited chapter for the book "Magnetic Fields in Diffuse Media", edited by Elisabete de Gouveia dal Pino and Alex Lazarian. Revised as per referee's recommendation