393 research outputs found

    Moderately Discontinuous Homology

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    We introduce a new metric homology theory, which we call Moderately Discontinuous Homology, designed to capture Lipschitz properties of metric singular subanalytic germs. The main novelty of our approach is to allow “moderately discontinuous” chains, which are specially advantageous for capturing the subtleties of the outer metric phenomena. Our invariant is a finitely generated graded abelian group (Formula presented.) for any (Formula presented.) and homomorphisms (Formula presented.) for any (Formula presented.). Here (Formula presented.) is a “discontinuity rate”. The homology groups of a subanalytic germ with the inner or outer metric are proved to be finitely generated and only finitely many homomorphisms (Formula presented.) are essential. For (Formula presented.) Moderately Discontinuous Homology recovers the homology of the tangent cone for the outer metric and of the Gromov tangent cone for the inner one. In general, for (Formula presented.) -Homology recovers the homology of the punctured germ. Hence, our invariant can be seen as an algebraic invariant interpolating from the germ to its tangent cone. Our homology theory is a bi-Lipschitz subanalytic invariant, is invariant by suitable metric homotopies, and satisfies versions of the relative and Mayer-Vietoris long exact sequences. Moreover, fixed a discontinuity rate b we show that it is functorial for a class of discontinuous Lipschitz maps, whose discontinuities are b-moderated; this makes the theory quite flexible. In the complex analytic setting we introduce an enhancement called Framed MD homology, which takes into account information from fundamental classes. As applications we prove that Moderately Discontinuous Homology characterizes smooth germs among all complex analytic germs, and recovers the number of irreducible components of complex analytic germs and the embedded topological type of plane branches. Framed MD homology recovers the topological type of any plane curve singularity and relative multiplicities of complex analytic germs. © 2020 Wiley Periodicals LLC

    Empresas familiares y sus decisiones de financiamiento : el impacto del grado de propiedad de la familia

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    La empresa familiar es uno de los tipos de estructura organizacional m?s antiguos del mundo, adem?s de ser uno de los m?s relevantes para la econom?a de los pa?ses, debido a la generaci?n de empleo, aporte al PBI e influencia en la sociedad. Una de las caracter?sticas m?s destacadas de este tipo organizativo es la trascendencia de la propiedad y control de generaci?n en generaci?n a trav?s de uno o m?s integrantes de la familia. Si bien las empresas familiares cuentan con gran popularidad, existe tambi?n un alto porcentaje de quiebra de las mismas, siendo explicada en gran medida por las decisiones de financiamiento que resultan en problemas para honrar sus obligaciones financieras. Es as? que las decisiones de financiamiento juegan un papel muy importante para la subsistencia de toda empresa y en especial para las familiares, debido a que ?stas tienen como uno de sus principales objetivos el mantener el control de la organizaci?n por parte de la misma familia lo que genera dificultades particulares. Por tal raz?n, el grado de propiedad de las familias en las empresas se considera que ejerce un especial impacto en las decisiones de financiamiento. Conociendo y analizando estudios realizados con anterioridad que sirven de base para la presente investigaci?n se realiza esta tesis con el objetivo de poder analizar el impacto del grado de propiedad en las decisiones de financiamiento de la muestra de empresas familiares analizada

    Conducting retrospective impact analysis to inform a medical research charity’s funding strategies: The case of Asthma UK

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    © 2013 Hanney et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.BACKGROUND: Debate is intensifying about how to assess the full range of impacts from medical research. Complexity increases when assessing the diverse funding streams of funders such as Asthma UK, a charitable patient organisation supporting medical research to benefit people with asthma. This paper aims to describe the various impacts identified from a range of Asthma UK research, and explore how Asthma UK utilised the characteristics of successful funding approaches to inform future research strategies. METHODS: We adapted the Payback Framework, using it both in a survey and to help structure interviews, documentary analysis, and case studies. We sent surveys to 153 lead researchers of projects, plus 10 past research fellows, and also conducted 14 detailed case studies. These covered nine projects and two fellowships, in addition to the innovative case studies on the professorial chairs (funded since 1988) and the MRC-Asthma UK Centre in Allergic Mechanisms of Asthma (the ‘Centre’) which together facilitated a comprehensive analysis of the whole funding portfolio. We organised each case study to capture whatever academic and wider societal impacts (or payback) might have arisen given the diverse timescales, size of funding involved, and extent to which Asthma UK funding contributed to the impacts. RESULTS: Projects recorded an average of four peer-reviewed journal articles. Together the chairs reported over 500 papers. All streams of funding attracted follow-on funding. Each of the various categories of societal impacts arose from only a minority of individual projects and fellowships. Some of the research portfolio is influencing asthma-related clinical guidelines, and some contributing to product development. The latter includes potentially major breakthroughs in asthma therapies (in immunotherapy, and new inhaled drugs) trialled by university spin-out companies. Such research-informed guidelines and medicines can, in turn, contribute to health improvements. The role of the chairs and the pioneering collaborative Centre is shown as being particularly important. CONCLUSIONS: We systematically demonstrate that all types of Asthma UK’s research funding assessed are making impacts at different levels, but the main societal impacts from projects and fellowships come from a minority of those funded. Asthma UK used the study’s findings, especially in relation to the Centre, to inform research funding strategies to promote the achievement of impact.This study was funded by Asthma UK

    Proyecto Especial T?nel Trasandino para Trasvase de Agua ? PET 2

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    El presente trabajo de investigaci?n, es el desarrollo de la planificaci?n y la aprobaci?n del Plan para la Direcci?n del Proyecto Especial T?nel Trasandino para Trasvase de Agua - PET 2, tomando en cuenta el marco de trabajo del PMBOK. Previo al Plan se realiz? un an?lisis PESTEL para analizar el encaje del proyecto en la organizaci?n de Icosaedro, identificando los criterios que se utilizaron para ser seleccionado por la empresa. El proyecto inici? tras la firma del contrato entre la empresa ICOSAEDRO y el Proyecto Especial de Irrigaci?n e Hidroenerg?tico Alto Piura (PEIHAP); identificando los stakeholders, definiendo los objetivos del proyecto, los objetivos del producto y el alcance del proyecto y producto; con los cuales se elabor? la Estructura de Desglose de Trabajo (EDT): procediendo luego a elaborar cada uno de los planes subsidiarios del proyecto: Plan de Gesti?n del Alcance, Plan de Gesti?n del Cronograma, Plan de Gesti?n de Costos, Plan de Gesti?n de Comunicaciones, Plan de Gesti?n de Riesgo, Plan de Gesti?n de Calidad y Plan de Gesti?n de Adquisiciones, etc

    Volumetric study of the maxillary sinus in patients with sinus pathology

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    OBJECTIVES: The aim of this study is 1) to obtain the area and volumes of the maxillary sinuses in patients affected by clinically unilateral sinus pathology by comparing the results to the contralateral sinus and 2) to determine the importance of the volumetric measures when diagnosing the percentage of sinus obliteration. MATERIALS AND METHODS: A single-centre observational retrospective clinical study was conducted in 214 patients with clinically unilateral sinus pathologies. Linear (mm), area (mm2) and volume (mm3) measurements were taken from Cone Beam Computed Tomography (CBCT) images of the affected sinus as well as from the contralateral ones. Histopathological study was performed using haematoxylin/eosin and PAS or Groccot stains. The lesions were classified into non-specific sinusitis, polyps, inverted papilloma, fungal sinusitis, cysts, mucocele and other lesions. Chi-squared test, ANOVA for independent samples and Pearson test were used for the statistical analysis. RESULTS: A total of 100 sinuses were measured in 50 patients (28 men and 22 women, with an age of 43.6 years (SD = 18.3), 50 pathological and 50 healthy contralateral sinuses. The three-dimensional occupation volume of the affected sinuses was 97.1 mm3 (62.5%) vs. 40.6 mm3 (22.8%) in the healthy ones (p<0.0001). The medial-lateral width of the sinus in the frontal plane was significantly higher in the cysts group (32.4 mm, CI: 23-41.8 mm). CONCLUSION: In medical terms, the global percentage of occupation determined using the classic manual determination method does not differ from the three-dimensional percentage calculated using specific complex software

    The Impact of Fuelwood Moisture Content on the Emission of Gaseous and Particulate Pollutants from a Wood Stove

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    The amount of moisture in wood fuel has a significant influence on the emissions of particulate matter (PM) and gaseous pollutants when burned in small-scale domestic appliances. Previous studies have shown that higher moisture content generally produces higher particulate emissions factors. As well as quantity of material emitted, it is also important to understand the effects of moisture on particle qualities including size, composition and morphology – since these can influence the human-toxicity and environmental impacts of the particles. In this study, emissions were quantified and the particulate qualities were also examined using chemical, optical and thermogravimetric analysis as well as size-graded sampling. By comparing the results from the use of batches of beech wood fuel with differing moisture content, it was shown that there are consistent and significant differences in both the quantity and qualities of the resulting emissions when burned under the same conditions. This has important consequences for emission inventories which currently only assume an emission factor from a proscribed combustion situatio

    Clinicopathological features of 214 maxillary sinus pathologies. A ten-year single-centre retrospective clinical study

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    BACKGROUND: Diagnosis of maxillary sinus pathology must include the clinical radiological study (CRS) and histopathological analysis. The aim of this study is 1) to describe the clinicopathological features of maxillary sinus lesions, obtained successively in a single medical centre over the last 10 years and 2) to determine the sensitivity and specificity for the diagnosis of malignant lesions based exclusively on the CRS. METHODS: It is a single-centre observational retrospective clinical study on patients who attended the University Hospital Complex of Santiago de Compostela (CHUS) with sinus pathologies during the period of 2009-2019. RESULTS: The sample consisted of 133 men (62.1%) and 81 women (37.9%), with an average age of 46.9 years (SD = 18.8). In terms of frequency, the most frequent pathology was the unspecified sinusitis (44.4%), followed by polyps (18.2%), malignant tumours (9.8%), inverting papilloma (7.5%), fungal sinusitis (4.7%), cysts (3.7%), benign tumours (2.3%), mucocele (2.3%) and other lesions (1.9%). Cysts and benign tumours were diagnosed earliest Vs malignant tumours (65.2 years (SD = 16.1)) were diagnosed the latest (p < 0.001). Based only on the CRS for malignancies, diagnostic indexes were 71.4% sensitivity and 97.9% specificity, with a Kappa value of 0.68 with (p < 0.001). CONCLUSION: Maxillary sinus pathology is very varied with therapeutic and prognostic repercussions. CRS is sometimes insufficient and histopathological confirmation is essential
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