227 research outputs found

    Novel dual single sided silicon strip detector chip for radiotherapy verification

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    A novel dual single sided silicon strip detector (SSSSD) chip was designed to meet clinical requirements in radiotherapy verification. An available design from Micron Semiconductor Ltd. (BB7, 500 µ m thick) was the base of a two-dimensional detector adapted into a special configuration with the aim of uniforming and minimizing foreing materials around the active area (64 × 64 mm2). With this purpose, two independent BB7 SSSSDs were mounted in a perpendicular configuration, separated by a 500 µ m kapton dielectric film with the same dimensions as the silicon wafers, thus minimizing air gaps in between. This new configuration, called the dual SSSSD chip design, was mounted on kapton printed circuit board (PCB). Both silicon wafers were divided into 32 strips, 2 mm width each. The aim of developing this detector was to allow 2D dose measurements, improve spatial resolution and perform radiotherapy treatment verification faster than with a previous prototype. Characteristics and performance of the novel detector are presented

    Seasonal and Long-Term Variability of the Mixed Layer Depth and its Influence on Ocean Productivity in the Spanish Gulf of Cádiz and Mediterranean Sea

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    The warming of the surface ocean is expected to increase the stratification of the upper water column. This would decrease the efficiency of the wind-induced mixing, reducing the nutrient supply to the euphotic layer and the productivity of the oceans. Climatic projections show that the Mediterranean Sea will experience a strong warming and salting along the twenty first century. Nevertheless, very few works have found and quantified changes in the water column stratification of the Western Mediterranean. In this work, we obtain time series of Mixed Layer Depth (MLD) along the Spanish Mediterranean waters and the Gulf of Cádiz, using periodic CTD profiles collected under the umbrella of the Ocean Observing system of the Instituto Español de Oceanografía (IEO-CSIC). The length of the time series analyzed is variable, depending on the geographical area, but in some cases these time series extend from the beginning of the 1990s decade. Our results show that at present, no statistically significant changes can be detected. These results are confirmed by the analysis of MLD time series obtained from Argo profilers. Some of the meteorological factors that could affect the water column stratification (wind intensity and precipitation rates) did not experience significant changes for the 1990-2021 period, neither were observed long-term changes in the chlorophyll concentration. The hypothesis proposed to explain this lack of trends, is that the salinity increase of the surface waters has compensated for the warming, and consequently, the density of the upper layer of the Western Mediterranean (WMED) has remained constant. As the wind intensity has not experienced significant trends, the stratification of the Spanish Mediterranean waters and those of the Gulf of Cádiz would have not been affected. Nevertheless, we do not discard that our results are a consequence of the short length of the available time series and the large variance of the variables analyzed, evidencing the importance of the maintenance of the ocean monitoring programs.En prens

    Radia2: A New Tool for Radiotherapy Verification

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    Radiotherapy is nowadays a proven technique in cancer treatments. Within the evolution of radiotherapy treatments towards more complex techniques, the need of new dosimetric methods for treatment verifications has appeared. In order to reach an improved dosimetric method, a collaboration was started to transfer knowledge from nuclear reaction instrumentation to medical applications, involving several departments from the University of Seville, Centro Nacional de Aceleradores (CNA), the Hospital Universitario Virgen Macarena and the company Inabensa. The first prototype, patent pending [2], gave very promising results. Currently, a critical review is being carried out to create an improved system

    The evolution of the zooplankton community in the gulf of Cadiz, SW Iberian Peninsula

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    The Spanish Institute of Oceanography (IEO) has been conducting a multidisciplinary study of the marine ecosystem in the Gulf of Cadiz (GoC; SW Iberian Peninsula) since 2009 within the frame of the program Time Series of Oceanographic data in the Gulf of Cadiz (STOCA, in Spanish). The program maintains repeated observations along five across-shelf transects: three times a year from 2009 to 2012 and quarterly on hereafter. In this paper we present the temporal evolution of the zooplankton community in the GoC. In particular, we focused on samples from three stations located off the Guadalquivir river mouth: GD1 (20 m depth), GD3 (80 m) and GD6 (450 m). Samples were taken with bongo-40 cm paired zooplankton nets (mesh size 200 mm). Double oblique hauls were conducted from top to bottom or to a maximum depth of 200 m) while the ship was steaming at 2.5 kn. A total of 43 samples per station were included in the analysis. Samples were imaged with ZooScan. Full images were processed with ZooProcess which generated set of associated features measured on each identified object (Gorsky et al, 2010). These objects were sorted following a common taxonomic guide using the web application EcoTaxa (http://ecotaxa.obs-vlfr.fr). As a sanity check, a variable number of aliquots were directly identified by light microscopy. These results permitted the description of the mean and variable components of the plankton community, their seasonal in the context of the thermohaline and transport variability in the 2010s

    IFNL4 ss469415590 polymorphism is associated with unfavourable clinical and immunological status in HIV-infected individuals

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    AbstractThe IFNL4 ss469415590 polymorphism, in high linkage disequilibrium with the IL28B rs12979860 variant, has been associated with hepatitis C virus clearance. We evaluated whether ss469415590 is associated with clinical and immunovirological parameters in human immunodeficiency virus-infected subjects. We found an independent association of the IFNL4 ss469415590 polymorphism with higher prevalence of AIDS-defining illnesses and lower CD4 T cell numbers. These results suggest the existence of common host defence mechanisms against different viral infections

    Guía práctica para el estudio del crecimiento de especies demersales en el Área ICES

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    Versión revisada 05-02-2015En el documento se presenta una síntesis de los métodos empleados para estudiar el crecimiento y la edad, mediante estructuras calcificadas (otolitos y vértebras), de las especies ícticas de interés comercial para la flota española en el área del ICES. El estudio de estas especies forma parte del requerimiento que la Comisión Europea ha establecido para el Programa Español de Recopilación, Gestión y Uso de Datos Pesqueros (PNDB) en base a los desembarcos nacionales, según establece la normativa vigente de la Unión Europea (UE). En este Programa está involucrado el Instituto Español de Oceanografía (IEO), y entre otros el proyecto BIODEMER, desarrollado en el Centro Oceanográfico de Vigo. Las especies objeto de estudio en este proyecto son: merluza ("Merluccius merluccius"), abadejo ("Pollachius pollachius"), congrio ("Conger conger"), faneca ("Trisopterus luscus"), gallineta ("Helicolenus dactylopterus"), locha ("Phycis blennoides"), maruca ("Molva molva"), maruca española ("Molva macrophthalma"), mendo ("Glyptocephalus cynoglossus"); incluyendo las especies de descarte: arete ("Chelidonichthys cuculus") y goyeta ("Microchirus variegatus"). Para complementar este documento se ha adjuntado el anexo: Fichas técnicas de Biología y crecimiento de 11 especies demersales en el área ICES, en el que se detallan para cada especie los protocolos aplicados en la interpretación de la edad. Para cada caso se incluye una revisión de la bibliografía existente, así como de los talleres e intercambios realizados sobre estudios de crecimiento y edad
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