24 research outputs found

    Dark Energy Survey year 3 results: covariance modelling and its impact on parameter estimation and quality of fit

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    We describe and test the fiducial covariance matrix model for the combined two-point function analysis of the Dark Energy Survey Year 3 (DES-Y3) data set. Using a variety of new ansatzes for covariance modelling and testing, we validate the assumptions and approximations of this model. These include the assumption of Gaussian likelihood, the trispectrum contribution to the covariance, the impact of evaluating the model at a wrong set of parameters, the impact of masking and survey geometry, deviations from Poissonian shot noise, galaxy weighting schemes, and other sub-dominant effects. We find that our covariance model is robust and that its approximations have little impact on goodness of fit and parameter estimation. The largest impact on best-fitting figure-of-merit arises from the so-called fsky approximation for dealing with finite survey area, which on average increases the χ2 between maximum posterior model and measurement by 3.7 per cent (Δχ2 ≈ 18.9). Standard methods to go beyond this approximation fail for DES-Y3, but we derive an approximate scheme to deal with these features. For parameter estimation, our ignorance of the exact parameters at which to evaluate our covariance model causes the dominant effect. We find that it increases the scatter of maximum posterior values for Ωm and σ8 by about 3 per cent and for the dark energy equation-of-state parameter by about 5 per cent⁠

    Measuring cumulative effects in a fragmented landscape

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Scientists recognize the importance of studying cumulative environmental effects as stressors, as there are countless stressors in human and technological development. However, existing studies acknowledge methodological limitations of measuring effects that combine and accumulate over time, making it difficult to interpret the processes leading to a given current landscape. Therefore, the objective of this study was to develop a method that would make it possible to define the sequence of human actions and to measure relationships between type, intensity and distribution of cumulative effects by analyzing the past and present composition of the landscape. The method is based on the identification of the cumulative value of effects in landscape units of 900 m(2). The chronosequence of human activities triggering accumulated effects was obtained from superimposed maps and the magnitude of effects was evaluated using area graphs. The method proposed was applied in a study area, resulting in a map that clearly showed the distribution and synergy of cumulative effects in the study area. (C) 2012 Elsevier B.V. All rights reserved.2288995Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Nursing’s role in tuberculosis control: a discussion from the perspective of equity El rol de la enfermería em el control de la tuberculosis: uma discusión desde la perspectiva de la equidad O papel da enfermagem no controle da tuberculose: uma discussão sob a perspectiva da equidade

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    This paper aims to analyze nurses’ role in tuberculosis control from the perspective of equity in the context of Latin American countries. Tuberculosis is frequently associated with poverty, but many other determinants play an important role in its prevalence. Latin American countries fight against the presence of this illness and nursing professionals play a protagonist role in TB control, proposing comprehensive interventions in different spheres - individuals, families and society. The focus of nursing intervention ranges from public policy proposals, based on epidemiological research, through the establishment of multi-sector programs, to direct care and client education at the operative level. Different professional nursing institutions can play a decisive role in this problem’ integral approach, both in national and international scopes. This requires the establishment of educative, social, technical and politically integrated support networks.<br>El objetivo del presente artículo es analizar el rol de la enfermera en el control de la tuberculosis desde la perspectiva de la equidad, en el ámbito de los países latinoamericanos. La tuberculosis está asociada frecuentemente con la pobreza, pero muchos otros determinantes juegan un rol importante en su prevalencia. Los países latinoamericanos luchan contra la presencia de esta enfermedad y la enfermería juega un rol protagónico en el control de este problema planteando intervenciones integrales en diferentes esferas del individuo, de la familia y de la sociedad. La intervención de enfermería se extiende desde el planteamiento de políticas públicas, basadas en estudios de base epidemiológica, mediante la implementación de programas multisectoriales, hasta la atención directa y la educación de los usuarios en el plan operativo. Las diferentes instituciones profesionales de enfermería pueden desarrollar un papel decisivo en el abordaje integral del problema, no sólo en el ámbito nacional sino también en el internacional, para esto se requiere establecer redes de apoyo con integración educativa, social, técnica y política.<br>O objetivo do presente artigo foi analisar o papel do profissional da enfermagem no controle da tuberculose, sob a perspectiva da equidade, no âmbito dos países da América Latina. A tuberculose está frequentemente associada à pobreza, mas muitos outros determinantes contribuem de modo importante para sua prevalência. Os países sul-americanos lutam contra essa enfermidade e a enfermagem possui papel de protagonista no controle desse problema, reivindicando intervenções integrais, voltadas para as diferentes esferas: individual, familiar e social. A intervenção da enfermagem é enfocada desde o desenho das políticas públicas, com base em estudos epidemiológicos, mediante a implementação de programas multissetoriais, até a assistência direta e a educação dos usuários no plano operativo. Diferentes instituições profissionais da enfermagem podem desenvolver atuação decisiva para a abordagem integral do problema, no âmbito nacional e internacional, devendo, para isso, estabelecer redes de apoio integradas às dimensões educativas, social, técnica e política
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