74 research outputs found

    Hopf Galois structures on symmetric and alternating extensions

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    By using a recent theorem by Koch, Kohl, Truman and Underwood on normality, we determine that some types of Hopf Galois structures do not occur on Galois extensions with Galois group isomorphic to alternating or symmetric groups. Our theory of induced Hopf Galois structures allows us to obtain the whole picture of types of Hopf Galois structures on A4-extensions, S4-extensions, and S5-extensions. Combining it with a result of Carnahan and Childs, we obtain a complete count of the Hopf Galois structures on S5-extensions.Peer ReviewedPostprint (author's final draft

    Left braces of size 8 p

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    We describe all left braces aof size 8 p for an odd p diferent from 3 and 7.Postprint (author's final draft

    On the Galois correspondence theorem in separable Hopf Galois theory

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    In this paper we present a reformulation of the Galois correspondence theorem of Hopf Galois theory in terms of groups carrying farther the description of Greither and Pareigis. We prove that the class of Hopf Galois extensions for which the Galois correspondence is bijective is larger than the class of almost classically Galois extensions but not equal to the whole class. We show as well that the image of the Galois correspondence does not determine the Hopf Galois structure.Peer ReviewedPostprint (author's final draft

    Direct Oral Anticoagulants versus Warfarin in Octogenarians with Nonvalvular Atrial Fibrillation: A Systematic Review and Meta-Analysis

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    Direct oral anticoagulants (DOACs) have been demonstrated to be more effective and safer than vitamin-K antagonist (VKA) for stroke prevention in patients with nonvalvular atrial fibrillation (AF). This meta-analysis aims to assess the effect of DOACS vs. VKA in patients ≥ 80 and AF. Primary endpoints were stroke or systemic embolism and all-cause death. Secondary endpoints included major bleeding, intracranial bleeding, and gastrointestinal bleeding. A random-effects model was selected due to significant heterogeneity. A total of 147,067 patients from 16 studies were included, 71,913 (48.90%) treated with DOACs and 75,154 with VKA (51.10%). The stroke rate was significantly lower in DOACs group compared with warfarin group (Relative risk (RR): 0.72; 95% confidence interval (CI): 0.63-0.82; p < 0.001). All-cause mortality was significantly lower in DOACs group compared with warfarin group (RR: 0.82; 95% CI: 0.70-0.96; p = 0.012). Compared to warfarin, DOACs were not associated with reductions in major bleeding (RR: 0.85, 95% CI 0.69-1.04; p = 0.108) or gastrointestinal bleeding risk (RR: 1.08, 95% CI 0.76-1.53; p = 0.678) but a 43% reduction of intracranial bleeding (RR: 0.47, IC 95% 0.36-0.60; p < 0.001) was observed. Our meta-analysis demonstrates that DOACs are effective and safe with statistical superiority when compared with warfarin in octogenarians with AF

    Multidimensional instruments with an integral approach to identify frailty in community-dwelling people: protocol for a systematic psychometric review

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    Introduction An increasing number of investigations highlight the complex nature of frailty; therefore, the use of multidimensional assessment instruments could be useful in clinical decision-making. Frail people are found mainly in the community setting which is why this is the ideal environment for early screening and intervention. For this purpose, it is necessary to have valid, time-effective and easy-to-use frailty assessment instruments. The aim of this review is to critically appraise, compare and summarise the quality of the measurement properties of all multidimensional instruments with an integral approach to identify frailty in community-dwelling people. Methods and analysis Medline, Psychological Information Database (PsycINFO) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) will be searched from their inception dates. We will also conduct searches in databases of grey literature. No limits will be applied for language. A highly sensitive validated search filter will be used for finding studies on measurement properties. An additional search including the names of the instruments found in the initial search will also be undertaken. Studies aiming at the development of a measurement instrument, the evaluation of one or more measurement properties or the evaluation of its interpretability will be included. The instrument should have an integral approach (physical, psychological and social) and it should measure all three domains. The context of use should be a community setting. Two reviewers independently will screen the references and assess the risk of bias by consensus-based standards for the selection of health measurement instruments checklist. To assess the overall evidence for the measurement properties of the identified instruments, the results of the different studies, adjusted for their methodological quality, will be combined. Ethics and dissemination Ethical approval and patient consent are not required as this is a psychometric review based on published studies. The results of this review will be disseminated at conferences and published in an international peer-reviewed journal. PROSPERO registration number CRD42019120212

    Desarrollo y evaluación de competencias para el ejercicio profesional farmacéutico en entornos simulados

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    Publicado dentro del libro "Innovación Docente Universitaria en Entornos de Aprendizaje Enriquecido" como resultado de las "V Jornadas de Redes de Investigación en Innovación Docente" organizadas por la Universidad Nacional de Educación a Distancia (UNED) 2012.Introducción y Objetivos: El objetivo del trabajo ha sido realizar actividades prácticas en sus contextos profesionales simulados, dirigidas a desarrollar competencias para: comunicación con el paciente, difusión de resultados científicos y realización de actividades de garantía de calidad. Resultados/desarrollo. Se han impartido prácticas de cinco asignaturas del Grado y Posgrado de Farmacia en la isla USALPHARMA del mundo virtual Second Life® (SL), durante los dos últimos cursos. Los entornos virtuales utilizados han sido: una Oficina de Farmacia, un laboratorio de la Industria Farmacéutica y espacios para presentación de comunicaciones a Congresos. Las prácticas han permitido conseguir los objetivos docentes específicos de cada asignatura. Se ha puesto de manifiesto la necesidad de entrenar a los estudiantes en competencias profesionales para aplicar en situaciones reales los conocimientos adquiridos. La valoración del alumnado de esta innovadora herramienta ha sido muy satisfactoria. Conclusión: Los mundos virtuales son una herramienta muy útil para el desarrollo de competencias en entornos profesionales, pudiendo interaccionar profesores y estudiantes desde cualquier lugar

    The impact from survey depth and resolution on the morphological classification of galaxies

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    We consistently analyse for the first time the impact of survey depth and spatial resolution on the most used morphological parameters for classifying galaxies through non-parametric methods: Abraham and Conselice-Bershady concentration indices, Gini, M20moment of light, asymmetry, and smoothness. Three different non-local data sets are used, Advanced Large Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) and Subaru/XMMNewton Deep Survey (SXDS, examples of deep ground-based surveys), and Cosmos Evolution Survey (COSMOS, deep space-based survey). We used a sample of 3000 local, visually classified galaxies, measuring their morphological parameters at their real redshifts (z ~ 0). Then we simulated them to match the redshift and magnitude distributions of galaxies in the non-local surveys. The comparisons of the two sets allow us to put constraints on the use of each parameter for morphological classification and evaluate the effectiveness of the commonly used morphological diagnostic diagrams. All analysed parameters suffer from biases related to spatial resolution and depth, the impact of the former being much stronger. When including asymmetry and smoothness in classification diagrams, the noise effects must be taken into account carefully, especially for ground-based surveys. M20 is significantly affected, changing both the shape and range of its distribution at all brightness levels. We suggest that diagnostic diagrams based on 2-3 parameters should be avoided when classifying galaxies in ground-based surveys, independently of their brightness; for COSMOS they should be avoided for galaxies fainter than F814 = 23.0. These results can be applied directly to surveys similar to ALHAMBRA, SXDS and COSMOS, and also can serve as an upper/lower limit for shallower/deeper ones.MP acknowledge financial support from JAE-Doc programme of the Spanish National Research Council (CSIC), co-funded by the European Social Fund. This research was supported by the Junta de Andalucia through project TIC114, and the Spanish Ministry of Economy and Competitiveness (MINECO) through projects AYA2010-15169, AYA2013-42227-P, and AYA2013-43188-P.Peer Reviewe
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