130 research outputs found

    Functional ecology of the biological soil crust in semiarid SE Spain: sun and shade populations of Diploschistes diacapsis (Ach.) Lumbsch

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    The Tabernas badlands in semiarid south-east Spain is one of the driest regions in Europe with a mean annual precipitation of c. 240 mm. The landscape is deeply dissected, with canyons, ramblas and sparsely vegetated eroded badland slopes. The vegetation is predominantly a biological soil crust consisting of different types of lichen-rich communities, one of the more conspicuous being dominated by Diploschistes diacapsis (Ach.) Lumbsch. This lichen is mainly restricted to the north- facing slopes, where it forms extensive whitish carpets and probably plays an important role in preventing erosion of the slopes and allowing plant colonization. South-facing slopes are much more eroded and generally lack vegetation. %The photosynthetic performance of north (shade) and south-facing (sun) populations of D. diacapsis was studied to determine if these different populations showed any adaptations to the microclimatic conditions of their individual habitats. The response of CO2 exchange to light intensity, temperature and water content was measured under controlled conditions in the laboratory. Dry weight-based net photosynthetic rates were higher in the southern-exposed population but quantum efficiency, and light compensation points were similar. Thallus weight per unit area (LMA) was considerably higher for shade specimens but maximum water content and optimal water content were very similar and chlorophyll content on a dry weight basis was also similar. Chlorophyll content on an area basis was higher in the northern-exposed population and always much larger than those reported in other studies on the same species (up to 8 times larger) with the result that NP values on a chlorophyll basis were relatively low. The larger LMA meant that shade thalli stored more water per unit area which should ensure longer active periods than sun thalli. The results support a strategy pair of high NP and short active time versus low NP and long active time, both having been reported for other soil crust species. However, the visibly larger biomass of the shade D. diacapsis suggests that the lichen is at the limit of its adaptability in these habitats

    An OGSA Middleware for Managing Medical Images Using Ontologies

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    The final publication is available at Springer via http://dx.doi.org/ 10.1007/s10877-005-0675-0This article presents a Middleware based on Grid Technologies that addresses the problem of sharing, transferring and processing DICOM medical images in a distributed environment using an ontological schema to create virtual communities and to define common targets. It defines a distributed storage that builds-up virtual repositories integrating different individual image repositories providing global searching, progressive transmission, automatic encryption and pseudo-anonimisation and a link to remote processing services. Users from a Virtual Organisation can share the cases that are relevant for their communities or research areas, epidemiological studies or even deeper analysis of complex individual cases. Software architecture has been defined for solving the problems that has been exposed before. Briefly, the architecture comprises five layers (from the more physical layer to the more logical layer) based in Grid Thecnologies. The lowest level layers (Core Middleware Layer and Server Services layer) are composed of Grid Services that implement the global managing of resources. The Middleware Components Layer provides a transparent view of the Grid environment and it has been the main objective of this work. Finally, the upest layer (the Application Layer) comprises the applications, and a simple application has been implemented for testing the components developed in the Components Middleware Layer. Other side-results of this work are the services developed in the Middleware Components Layer for managing DICOM images, creating virtual DICOM storages, progressive transmission, automatic encryption and pseudo-anonimisation depending on the ontologies. Other results, such as the Grid Services developed in the lowest layers, are also described in this article. Finally a brief performance analysis and several snapshots from the applications developed are shown. The performance analysis proves that the components developed in this work provide image processing applications with new possibilities for large-scale sharing, management and processing of DICOM images. The results show that the components fulfil the objectives proposed. The extensibility of the system is achieved by the use of open methods and protocols, so new components can be easily added.Blanquer Espert, I.; Hernández García, V.; Segrelles Quilis, JD. (2005). An OGSA Middleware for Managing Medical Images Using Ontologies. Journal of Clinical Monitoring and Computing. 19:295-305. doi:10.1007/s10877-005-0675-0S29530519“European DataGrid Project”. http://www.eu-datagrid.org.“Biomedical Informatics Research”. http://www.nbirn.net/.“ACI project MEDIGRID: medical data storage and processing on the GRID”.http://www.creatis.insa-lyon.fr/MEDIGRID/.“Information eXtraction from Images (IXI) Grid Services for Medical Imaging”. Working Notes of the Workshop on Distributed Databases and processing in Medical Image Computing (DIDAMIC'04). Pag 65.“NeuroBase: Management of Distributed and Heterogeneous Information Sources in Neuroimaging”. Working Notes of the Workshop on Distributed Databases and processing in Medical Image Computing (DIDAMIC'04). Pag 85.Digital Imaging and Communications in Medicine (DICOM) Part 10: Media Storage and File Format for Media Interchange. National Electrical Manufacturers Association, 1300 N. 17th Street, Rosslyn, Virginia 22209 USA.“Open Grid Services Architecture (OGSA)”, http://www.globus.org/ogsa.Globus alliance Home Page. “Relevant documents”, http://www.globus.orgAllen Wyke R, Watt A, “XML Schema Essentials”. Wiley Computer Pub. ISBN 0-471-412597Web security and commerce/Simson Garfinkel. - Cambridge: O'Reilly, 1997. - 483 p.; 23 cm. ISBN 1565922697“The GridFTP Protocol and Software”. http://www-fp.globus.org/datagrid/gridftp.html.JPEG2000: Image compression fundamentals, standards and practice/David S. Taubman, Michael W. Marcellin. – Boston [etc.] : Kluwer Academic, cop. 2002. - XIX, 773 p.; 24 cm. + 1 CD-Rom - (The Kluwer international series in engineering and computer science) ISBN 079237519XBradley J, Erickson MD, “Irreversible Compression of Medical Images”, Dpt. Radiology, Mayo F., Rochester, MN, Jo. of D. Imaging, DOI: 10.1007/s10278-002-0001-z, 02.Monitoring & Discovery System (MDS)” http://www-unix.globus.org/toolkit/mds/“Key management for encrypted data storage in distributed systems”. Proceedings of HeathGrid 2004

    Comparison of vibration and rolling noise emission of resilient and solid monobloc railway wheels in underground lines

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    Flat or worn wheels rolling on rough or corrugated tracks can provoke airborne noise and ground-borne vibration, which can be a serious concern for nearby neighbours of urban rail transit lines. Among the various treatments used to reduce vibration and noise, resilient wheels play an important role. In conventional resilient wheels, a slightly prestressed V­shaped rubber ring is mounted between the steel wheel centre and tyre. The elastic layer enhances rolling noise and vibration suppression, as well as impact reduction on the track. In this paper the effectiveness of resilient wheels in underground lines, in comparison to monobloc ones, is assessed. The analysed resilient wheel is able to carry greater loads than standard resilient wheels used for light vehicles. It also presents a greater radial resiliency and a higher axial stiffness than conventional V­wheels. The finite element method was used in this study. A quarter car model was defined, in which the wheelset was modelled as an elastic body. Several simulations were performed in order to assess the vibrational behaviour of elastic wheels, including modal, harmonic and random vibration analysis, the latter allowing the introduction of realistic vertical track irregularities, as well as the influence of the running speed. Due to numerical problems some simplifications were needed. Parametric variations were also performed, in which the sensitivity of the whole system to variations of rubber prestress and Poisson’s ratio of the elastic material was assessed.Results are presented in the frequency domain, showing a better performance of the resilient wheels for frequencies over 200 Hz. This result reveals the ability of the analyzed design to mitigate rolling noise, but not structural vibrations, which are primarily found in the lower frequency range

    Comparación de la emisión de vibraciones y ruido de ruedas ferroviarias elásticas y monobloque en líneas de metro

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    Las ruedas de ferrocarril con avanzado estado de desgaste o poligonalización pueden ser una fuente transmisora de ruidos y vibraciones, lo que supone un serio inconveniente para los vecinos próximos a la línea ferroviaria. Se han adoptado distintas soluciones para mitigar este efecto, entre las que las ruedas elásticas desempeñan un papel importante.Las ruedas elásticas convencionales presentan un anillo de goma, en forma de V, que se encuentra ligeramente comprimido entre el cubo y la banda de rodadura, construidos en acero. Esta capa elástica favorece la supresión del ruido y vibraciones transmitidos, al tiempo que reduce los impactos sobre la vía. En este estudio se ha valorado la eficacia de las ruedas elásticas en líneas metropolitanas, comparándolas con las ruedas monobloque. Se ha utilizado para ello el método de los elementos finitos. Se han llevado a cabo diversas simulaciones para estudiar el comportamiento vibratorio de las ruedas elásticas y monobloque, incluyendo análisis modal, respuesta en frecuencia y análisis de vibraciones estocásticas

    Enhancing Privacy and Authorization Control Scalability in the Grid through Ontologies

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    © 2009 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The use of data Grids for sharing relevant data has proven to be successful in many research disciplines. However, the use of these environments when personal data are involved (such as in health) is reduced due to its lack of trust. There are many approaches that provide encrypted storages and key shares to prevent the access from unauthorized users. However, these approaches are additional layers that should be managed along with the authorization policies. We present in this paper a privacy-enhancing technique that uses encryption and relates to the structure of the data and their organizations, providing a natural way to propagate authorization and also a framework that fits with many use cases. The paper describes the architecture and processes, and also shows results obtained in a medical imaging platform.Manuscript received November 19, 2007; revised July 27, 2008. First published August 4,2008; cur-rent version published January 4,2009. This work was supported in part by the Spanish Ministry of Education and Science to develop the project "ngGrid-New Generation Components for the Efficient Exploitation of eScience Infrastructures," under Grant TIN2006-12860 and in part by the Structural Funds of the European Regional Development Fund (ERDF).Blanquer Espert, I.; Hernández García, V.; Segrelles Quilis, JD.; Torres Serrano, E. (2009). Enhancing Privacy and Authorization Control Scalability in the Grid through Ontologies. IEEE Transactions on Information Technology in Biomedicine. 13(1):16-24. https://doi.org/10.1109/TITB.2008.2003369S162413

    Utilización de tecnologías móviles en pacientes con psicosis: una revisión sistemática.

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    [EN] There is a growing interest in mobile Health interventions (m-Health) in patients with psychosis. The aim of this study is to conduct a systematic review in order to analysethe current state of research in this area. The search of articles was carried out following the PRISMA criteria, focusing on those studies that used mobile technologies in patients with psychosis during the period from 1990 to 2016. A total of 20 articles were selected from the 431 studies found. Three types of studies are distinguished: 1) Analysis of quality and usability, 2) Improving treatment adherence and reducing hospital admissions, and 3) Analysisof patient symptoms. CONCLUSIONS: m-Health interventions are feasible, and are easy to use for patients with psychosis. They evaluate the evolution of psychotic symptoms more efficiently, and improve adherence to treatment, as well as symptoms and hospital admissions. However, a particular strategy does not stand out over the rest, because differences in methodology make them difficult to compare.[ES] Introducción: Hay un creciente interés en las intervenciones mobile Health (m-Health) en pacientes con psicosis. El objetivo de este estudio es realizar una revisión sistemática para analizar el estado actual de la investigación en este ámbito. Metodología: Búsqueda en las bases de datos PsycINFO, PubMED, SCOPUS, Medline, ISI Web of Knowledge e IME del CSIC. Intervenciones con tecnologías móviles en pacientes con psicosis. Resultados: De un total de 431 artículos se seleccionaron 20. Se diferencian tres tipos de intervenciones: (1) Análisis de calidad y usabilidad, (2) Mejora de la adherencia, síntomas y reducción de hospitalizaciones, (3) Análisis de la sintomatología del paciente. Conclusiones: Las intervenciones m-Health son viables y resultan fáciles de utilizar para los pacientes con psicosis. Evalúan de forma más eficiente la evolución de los síntomas psicóticos y mejoran la adherencia al tratamiento, síntomas y hospitalizaciones. No se puede destacar una estrategia sobre las demás debido a que las diferencias en la metodología las hace difícilmente comparables.A ‘‘Prometeo’’ support grant from the Conselleria de Sanidad de la Comunidad Valenciana.Bonet, L.; Izquierdo, C.; Escartí, MJ.; Sancho, JV.; Arce Grilo, AD.; Blanquer Espert, I.; Sanjuan Arias, J. (2017). Use of mobile technologies in patients with psychosis: A systematic review. Revista de Psiquiatría y Salud Mental. 10(3):168-178. doi:10.1016/j.rpsm.2017.01.003S16817810

    Tuberculosis treatment adherence and fatality in Spain

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    <p>Abstract</p> <p>Background</p> <p>The adherence to long tuberculosis (TB) treatment is a key factor in TB control programs. Always some patients abandon the treatment or die. The objective of this study is to identify factors associated with defaulting from or dying during antituberculosis treatment.</p> <p>Methods</p> <p>Prospective study of a large cohort of TB cases diagnosed during 2006-2007 by 61 members of the Spanish Society of Pneumology and Thoracic Surgery (SEPAR). Predictive factors of completion outcome (cured plus completed treatment vs. defaulters plus lost to follow-up) and fatality (died <it>vs. </it>the rest of patients) were based on logistic regression, calculating odds ratios (OR) and 95% confidence intervals (CI).</p> <p>Results</p> <p>Of the 1490 patients included, 29.7% were foreign-born. The treatment outcomes were: cured 792 (53.2%), completed treatment 540 (36.2%), failure 2 (0.1%), transfer-out 33 (2.2%), default 27 (1.8%), death 27 (1.8%), lost to follow-up 65 (4.4%), other 4 (0.3%). Completion outcome reached 93.5% and poor adherence was associated with: being an immigrant (OR = 2.03; CI:1.06-3.88), living alone (OR = 2.35; CI:1.05-5.26), residents of confined institutions (OR = 4.79; CI:1.74-13.14), previous treatment (OR = 2.93; CI:1.44-5.98), being an injecting drug user (IDU) (OR = 9.51; CI:2.70-33.47) and treatment comprehension difficulties (OR = 2.93; CI:1.44-5.98). Case fatality was 1.8% and it was associated with the following variables: age 50 or over (OR = 10.88; CI:1.12-105.01), retired (OR = 12.26;CI:1.74-86.04), HIV-infected (OR = 9.93; CI:1.48-66.34), comprehension difficulties (OR = 4.07; CI:1.24-13.29), IDU (OR = 23.59; CI:2.46-225.99) and Directly Observed Therapy (DOT) (OR = 3.54; CI:1.07-11.77).</p> <p>Conclusion</p> <p>Immigrants, those living alone, residents of confined institutions, patients treated previously, those with treatment comprehension difficulties, and IDU patients have poor adherence and should be targeted for DOT. To reduce fatality rates, stricter monitoring is required for patients who are retired, HIV-infected, IDU, and those with treatment comprehension difficulties.</p

    Improving knowledge management through the support of image examination and data annotation using DICOM structured reporting

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    [EN] An important effort has been invested on improving the image diagnosis process in different medical areas using information technologies. The field of medical imaging involves two main data types: medical imaging and reports. Developments based on the DICOM standard have demonstrated to be a convenient and widespread solution among the medical community. The main objective of this work is to design a Web application prototype that will be able to improve diagnosis and follow-on of breast cancer patients. It is based on TRENCADIS middleware, which provides a knowledge-oriented storage model composed by federated repositories of DICOM image studies and DICOM-SR medical reports. The full structure and contents of the diagnosis reports are used as metadata for indexing images. The TRENCADIS infrastructure takes full advantage of Grid technologies by deploying multi-resource grid services that enable multiple views (reports schemes) of the knowledge database. The paper presents a real deployment of such Web application prototype in the Dr. Peset Hospital providing radiologists with a tool to create, store and search diagnostic reports based on breast cancer explorations (mammography, magnetic resonance, ultrasound, pre-surgery biopsy and post-surgery biopsy), improving support for diagnostics decisions. A technical details for use cases (outlining enhanced multi-resource grid services communication and processing steps) and interactions between actors and the deployed prototype are described. As a result, information is more structured, the logic is clearer, network messages have been reduced and, in general, the system is more resistant to failures.The authors wish to thank the financial support received from The Spanish Ministry of Education and Science to develop the project "CodeCloud", with reference TIN2010-17804.Salavert Torres, J.; Segrelles Quilis, JD.; Blanquer Espert, I.; Hernández García, V. (2012). Improving knowledge management through the support of image examination and data annotation using DICOM structured reporting. Journal of Biomedical Informatics. 45(6):1066-1074. https://doi.org/10.1016/j.jbi.2012.07.004S1066107445
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