Clusters of galaxies : observational properties of the diffuse radio emission

Clusters of galaxies, as the largest virialized systems in the Universe, are ideal laboratories to study the formation and evolution of cosmic structures...(abridged)... Most of the detailed knowledge of galaxy clusters has been obtained in recent years from the study of ICM through X-ray Astronomy. At the same time, radio observations have proved that the ICM is mixed with non-thermal components, i.e. highly relativistic particles and large-scale magnetic fields, detected through their synchrotron emission. The knowledge of the properties of these non-thermal ICM components has increased significantly, owing to sensitive radio images and to the development of theoretical models. Diffuse synchrotron radio emission in the central and peripheral cluster regions has been found in many clusters. Moreover large-scale magnetic fields appear to be present in all galaxy clusters, as derived from Rotation Measure (RM) studies. Non-thermal components are linked to the cluster X-ray properties, and to the cluster evolutionary stage, and are crucial for a comprehensive physical description of the intracluster medium. They play an important role in the cluster formation and evolution. We review here the observational properties of diffuse non-thermal sources detected in galaxy clusters: halos, relics and mini-halos. We discuss their classification and properties. We report published results up to date and obtain and discuss statistical properties. We present the properties of large-scale magnetic fields in clusters and in even larger structures: filaments connecting galaxy clusters. We summarize the current models of the origin of these cluster components, and outline the improvements that are expected in this area from future developments thanks to the new generation of radio telescopes.Comment: Accepted for the publication in The Astronomy and Astrophysics Review. 58 pages, 26 figure

Resilience and physical and mental well-being in adults with and without HIV

Resilience has been related to improved physical and mental health, and is thought to improve with age. No studies have explored the relationship between resilience, ageing with HIV, and well-being. A cross sectional observational study performed on UK HIV positive (N = 195) and HIV negative adults (N = 130). Associations of both age and ‘time diagnosed with HIV’ with resilience (RS-14) were assessed, and the association of resilience with depression, anxiety symptoms (PHQ-9 and GAD-7), and problems with activities of daily living (ADLs) (Euroqol 5D-3L). In a multivariable model, HIV status overall was not related to resilience. However, longer time diagnosed with HIV was related to lower resilience, and older age showed a non-significant trend towards higher resilience. In adults with HIV, high resilience was related to a lower prevalence of depression, anxiety, and problems with ADLs. It may be necessary to consider resilience when exploring the well-being of adults ageing with HIV

Sintomatologia de depressão autorreferida por idosos que vivem em comunidade The symptomatology of self-referred depression by elderly people who live in a shantytown

Este estudo exploratório quantitativo objetivou avaliar a sintomatologia da depressão autorreferida por idosos, considerando variáveis sociodemográficas. Os dados coletados por meio de entrevista semiestruturada e da Escala de Depressão Geriátrica Abreviada envolvendo 240 idosos residentes em João Pessoa (PB), no período de outubro a dezembro de 2010, foram analisados pelos softwares Excel e SPSS. Verificou-se que 75,8% não apresentaram grau de sintomatologia de depressão e 24,2% manifestaram depressão leve ou severa. De acordo com essas varáveis, nesses idosos com grau depressivo verificou-se que: em relação à faixa etária, aqueles com grau depressivo leve e severo destacam maior frequência entre 71 a 76 anos, 31,0%; com relação ao gênero, o feminino destaca-se com 86,0%; sobre o estado civil, os casados com 41,3% e os viúvos com 34,5%; considerando-se a renda familiar, os de 01 até 03 salários mínimos, 50%, apresentaram grau leve; com vistas à escolaridade, dos que não evidenciaram grau de depressão, 84,6%, sabem ler e escrever. Portanto, pode afirmar-se que a sintomatologia da depressão em idosos apresenta relação com as condições socioeconômicas e culturais, fortalecendo a necessidade de políticas públicas de saúde que garantam um atendimento integral e de qualidade, considerando essas variáveis.<br>The scope of this quantitative exploratory study was to evaluate the symptomatology of self-referred depression by the elderly, taking socio-demographic variables into consideration. The data collected by means of semi-structured interviews and the Abbreviated Geriatric Depression Scale involving 240 elderly residents in João Pessoa in the state of Paraíba between October and December 2010 were analyzed by Excel and SPSS software. It was found that 75.8 % had no degree of symptomatology of depression, and 24.2 % manifested mild or severe depression. According to these variables, in the elderly patients with depression it was found that: in relation to age, the elderly with mild and severe depression appear more frequently between 71 to 76 years - 31%; in relation to gender, females stand out with 86%; on marital state, married couples with 41.3 %, and widowers with 34.5 %; considering family income, from 1 up to 3 minimum wages, 50 %, revealed mild incidence; with respect to schooling, elderly people who have no depression, 84.6 %, can read and write. Therefore, it can be said that the symptomatology of depression in the elderly is related to socio-economic and cultural conditions, emphasizing the need for public health policies that ensure comprehensive care and quality considering these variables