Ultra-compact and ultra-diffuse stellar systems in nearby galaxy clusters: signs of environmental influence?

In this thesis we investigate ultra-compact and ultra-diffuse stellar systems in the cores of the nearby Perseus and Fornax galaxy clusters for signs of environmental influences. We search for possible disturbances of their stellar structures by examining their light distributions in deep optical wide field imaging data. In the Fornax cluster we analyse a sample of 355 spectroscopically confirmed compact stellar systems. Our data reveal that many objects show distorted outer structures, although we do not find long tidal streams around any of them. We investigate their spatial and phase-space distributions, and interpret our results in the framework of proposed formation scenarios. In the Perseus cluster we identify a population of 89 diffuse low surface brightness galaxy candidates for which we perform photometry. The majority of the diffuse candidates appear unperturbed based on their stellar structures. We find, however, that galaxies with large sizes seem to be absent in the dense cluster core region. We discuss possible implications for the dark matter content of these systems and compare our sample to faint low surface brightness galaxies in the Coma cluster. Our data reveal a few low-mass galaxies with tidal tails or disturbed morphology, and several diffuse streams and tidal debris. Nevertheless, the number of recent galaxy disruption events seems to be very low in both the Perseus and Fornax galaxy cluster cores, indicating that most of the low-mass galaxy population was probably shaped at earlier epochs

A population of faint low surface brightness galaxies in the Perseus cluster core

We present the detection of 89 low surface brightness (LSB), and thus low stellar density galaxy candidates in the Perseus cluster core, of the kind named ‘ultra-diffuse galaxies’, with mean effective V-band surface brightnesses 24.8-27.1 mag arcsec−2, total V-band magnitudes −11.8 to −15.5 mag, and half-light radii 0.7-4.1 kpc. The candidates have been identified in a deep mosaic covering 0.3 square degrees, based on wide-field imaging data obtained with the William Herschel Telescope. We find that the LSB galaxy population is depleted in the cluster centre and only very few LSB candidates have half-light radii larger than 3 kpc. This appears consistent with an estimate of their tidal radius, which does not reach beyond the stellar extent even if we assume a high dark matter content (M/L = 100). In fact, three of our candidates seem to be associated with tidal streams, which points to their current disruption. Given that published data on faint LSB candidates in the Coma cluster – with its comparable central density to Perseus – show the same dearth of large objects in the core region, we conclude that these cannot survive the strong tides in the centres of massive clusters

A Catalog of Galaxies in the Direction of the Perseus Cluster

We present a catalog of 5437 morphologically classified sources in the direction of the Perseus galaxy cluster core, among them 496 early-type low-mass galaxy candidates. The catalog is primarily based on V-band imaging data acquired with the William Herschel Telescope, which we used to conduct automated source detection and derive photometry. We additionally reduced archival Subaru multiband imaging data in order to measure aperture colors and perform a morphological classification, benefiting from 0.″5 seeing conditions in the r-band data. Based on morphological and color properties, we extracted a sample of early-type low-mass galaxy candidates with absolute V-band magnitudes in the range of −10 to −20 mag. In the color─magnitude diagram, the galaxies are located where the red sequence for early-type cluster galaxies is expected, and they lie on the literature relation between absolute magnitude and Sérsic index. We classified the early-type dwarf candidates into nucleated and nonnucleated galaxies. For the faint candidates, we found a trend of increasing nucleation fraction toward brighter luminosity or higher surface brightness, similar to what is observed in other nearby galaxy clusters. We morphologically classified the remaining sources as likely background elliptical galaxies, late-type galaxies, edge-on disk galaxies, and likely merging systems and discussed the expected contamination fraction through non-early-type cluster galaxies in the magnitude-size surface brightness parameter space. Our catalog reaches its 50% completeness limit at an absolute V-band luminosity of −12 mag and a V-band surface brightness of 26 mag arcsec−2. This makes it the largest and deepest catalog with coherent coverage compared to previous imaging studies of the Perseus cluster.</p

Categorizing diffuse parenchymal lung disease in children

Background Aim of this study was to verify a systematic and practical categorization system that allows dynamic classification of pediatric DPLD irrespective of completeness of patient data. Methods The study was based on 2322 children submitted to the kids-lung-register between 1997 and 2012. Of these children 791 were assigned to 12 DPLD categories, more than 2/3 belonged to categories manifesting primarily in infancy. The work-flow of the pediatric DPLD categorization system included (i) the generation of a final working diagnosis, decision on the presence or absence of (ii) DPLD and (iii) a systemic or lung only condition, and (iv) the allocation to a category and subcategory. The validity and inter-observer dependency of this workflow was re-tested using a systematic sample of 100 cases. Results Two blinded raters allocated more than 80 % of the re-categorized cases identically. Non-identical allocation was due to lack of appreciation of all available details, insufficient knowledge of the classification rules by the raters, incomplete patient data, and shortcomings of the classification system itself. Conclusions This study provides a suitable workflow and hand-on rules for the categorization of pediatric DPLD. Potential pitfalls were identified and a foundation was laid for the development of consensus-based, international categorization guidelines

Corrigendum:The Fornax Deep Survey with the VSTIV. A size and magnitude limited catalog of dwarf galaxies in the area of the Fornax cluster (vol 57, pg 631, 2018)

An error occurred during the production process of the original article pertaining to the numbering of the figures beginning with Fig. 18. Figure 20 is incorrectly labeled and it should be named Fig. 18, and so on. However, the citations of the figures in the text are consistent with their respective image

Lung disease caused by ABCA3 mutations

Background Knowledge about the clinical spectrum of lung disease caused by variations in the ATP binding cassette subfamily A member 3 (ABCA3) gene is limited. Here we describe genotype-phenotype correlations in a European cohort. Methods We retrospectively analysed baseline and outcome characteristics of 40 patients with two disease-causing ABCA3 mutations collected between 2001 and 2015. Results Of 22 homozygous (15 male) and 18 compound heterozygous patients (3 male), 37 presented with neonatal respiratory distress syndrome as term babies. At follow-up, two major phenotypes are documented: patients with (1) early lethal mutations subdivided into (1a) dying within the first 6 months or (1b) before the age of 5 years, and (2) patients with prolonged survival into childhood, adolescence or adulthood. Patients with null/null mutations predicting complete ABCA3 deficiency died within the 1st weeks to months of life, while those with null/other or other/other mutations had a more variable presentation and outcome. Treatment with exogenous surfactant, systemic steroids, hydroxychloroquine and whole lung lavages had apparent but many times transient effects in individual subjects. Conclusions Overall long-term (>5 years) survival of subjects with two disease-causing ABCA3 mutations was <20%. Response to therapies needs to be ascertained in randomised controlled trials

The Fornax Deep Survey (FDS) with VST VI. Optical properties of the dwarf galaxies in the Fornax cluster

Context. Dwarf galaxies are the most common type of galaxies in galaxy clusters. Due to their low mass, they are more vulnerable to environmental effects than massive galaxies, and are thus optimal for studying the effects of the environment on galaxy evolution. By comparing the properties of dwarf galaxies with different masses, morphological types, and cluster-centric distances we can obtain information about the physical processes in clusters that play a role in the evolution of these objects and shape their properties. The Fornax Deep Survey Dwarf galaxy Catalog (FDSDC) includes 564 dwarf galaxies in the Fornax cluster and the in-falling Fornax A subgroup. This sample allows us to perform a robust statistical analysis of the structural and stellar population differences in the range of galactic environments within the Fornax cluster.Aims. By comparing our results with works concerning other clusters and the theoretical knowledge of the environmental processes taking place in galaxy clusters, we aim to understand the main mechanisms transforming galaxies in the Fornax cluster.Methods. We have exploited the FDSDC to study how the number density of galaxies, galaxy colors and structure change as a function of the cluster-centric distance, used as a proxy for the galactic environment and in-fall time. We also used deprojection methods to transform the observed shape and density distributions of the galaxies into the intrinsic physical values. These measurements are then compared with predictions of simple theoretical models of the effects of harassment and ram pressure stripping on galaxy structure. We used stellar population models to estimate the stellar masses, metallicities and ages of the dwarf galaxies. We compared the properties of the dwarf galaxies in Fornax with those in the other galaxy clusters with different masses.Results. We present the standard scaling relations for dwarf galaxies, which are the size-luminosity, Sersic n-magnitude and color-magnitude relations. New in this paper is that we find a different behavior for the bright dwarfs (18.5 mag -16 mag): While considering galaxies in the same magnitude-bins, we find that, while for fainter dwarfs the g' - r' color is redder for lower surface brightness objects (as expected from fading stellar populations), for brighter dwarfs the color is redder for the higher surface brightness and higher Sersic n objects. The trend of the bright dwarfs might be explained by those galaxies being affected by harassment and by slower quenching of star formation in their inner parts. As the fraction of early-type dwarfs with respect to late-types increases toward the central parts of the cluster, the color-surface brightness trends are also manifested in the cluster-centric trends, confirming that it is indeed the environment that changes the galaxies. We also estimate the strength of the ram-pressure stripping, tidal disruption, and harassment in the Fornax cluster, and find that our observations are consistent with the theoretically expected ranges of galaxy properties where each of those mechanisms dominate. We furthermore find that the luminosity function, color-magnitude relation, and axis-ratio distribution of the dwarfs in the center of the Fornax cluster are similar to those in the center of the Virgo cluster. This indicates that in spite of the fact that the Virgo is six times more massive, their central dwarf galaxy populations appear similar in the relations studied by us

Capacities of emotional intelligence in nurses: validation of a measurement instrument

Mestrado em Gestão Pública - Gestão de PessoasEsta investigação constitui a primeira deste tipo, em Portugal, sobre a inteligência emocional (IE) nos profissionais de enfermagem. Propõe-se divulgar um estudo exploratório e a validação de um instrumento de medida, com a finalidade de contribuir para a melhoria da gestão dos recursos humanos, para efeitos da organização e formação dos enfermeiros. O relatório divide-se fundamentalmente em duas partes. A primeira de fundamentação teórica e uma segunda, que corresponde ao estudo propriamente dito. Partindo da Escala Veiga Branco das Capacidades da Inteligência Emocional, à luz do modelo teórico de Daniel Goleman, procedeuse a um estudo de carácter exploratório, descritivo e correlacional, através dos métodos da investigação quantitativa. O instrumento foi validado numa amostra de 214 enfermeiros, recorrendo-se à análise factorial das componentes principais, na qual se obtiveram 17 factores correspondentes às cinco capacidades que compõem o conceito. Encontrouse um perfil de IE que corresponde à percepção dos enfermeiros relativamente às suas capacidades e à IE global, bem como algumas variáveis que parecem influenciar os factores, as capacidades e a IE. Estudaram-se as correlações existentes entre as capacidades e entre estas e a IE, tendo emergido desta última as variáveis preditivas. No final do estudo, e após a obtenção dos resultados, o autor deseja reunir alguns dados de interesse para a melhoria dos processos de formação e de gestão dos enfermeiros, bem como despertar para a utilidade deste tipo de inteligência na vida dos profissionais e das organizações.This investigation constitutes the first of its kind in Portugal on the concept of emotional intelligence (EI) in the nursing profession. The primary purpose of the study is to develop and validate an instrument on EI that will contribute to the improvement of human resources administration within organizations and specifically within the arena of nursing. The study essentially has two parts. The first is the theoretical foundations of the research, and the second is the investigation itself. Departing from the Veiga Branco Scale of the Capacities of Emotional Intelligence based on Daniel Goleman’s theoretical model, this study explores personal character through quantitative analyses of a descriptive and correlational nature. The instrument was validated from a sample of 214 nurses. Through factor analysis, 17 factors were identified that corresponded to the five capacities of EI. It was discovered an EI profile which corresponds to the perception of the nurses concerning its capacities and the global EI, moreover there are some variables which seem to influence the factors, the capacities and the EI. The existing correlations between the capacities and between these with the EI had been studied, having emerged of these last the predictive variables. Finally, the author examines and speculates on the findings, and offers suggestions for the improvement of nursing administration. Ultimately, the study points to the usefulness of understanding this form of intelligence in the professional and organizational realms of nursing.Esta investigación constituye la primera de este tipo en Portugal, sobre la inteligencia emocional (IE) en los profesionales de enfermería. Se propone divulgar un estudio exploratorio y la validación de un instrumento de medida, con la finalidad de contribuir para la mejoría de la gestión de los recursos humanos, para efectos de organización y formación de los enfermeros. El documento se divide fundamentalmente en dos partes. La primera con fundamentos teóricos y la segunda correspondiente al estudio propiamente dicho. Partiendo de la Escala Veiga Branco de las Capacidades de la Inteligencia Emocional, considerando el modelo teórico de Daniel Goleman, se procedió a un estudio de exploración, descriptivo y correlacional a través de los métodos de la investigación cuantitativa. El instrumento fue validado en una muestra de 214 enfermeros, a través del análisis factorial de los componentes principales, en la cual se obtuvieron 17 factores correspondientes a las cinco capacidades que componen el concepto. Se ha encontrado un perfil de IE que corresponde a la percepción de estos enfermeros relativamente a las suyas capacidades y a la IE global, bien como algunas variables que parecen influenciar los factores, las capacidades y la IE. Se estudiaran las correlaciones existentes entre las capacidades y entre estas y la IE, tiendo emergido dista última las variables explicativas. En la recta final del estudio, y después de la obtención de resultados, el autor desea reunir algunos datos de interés para la mejoría de los procesos de formación e de gestión de los enfermeros, así como el despertar del interés para la utilidad de este tipo de inteligencia en la vida de los profesionales y de las organizaciones