Mass distribution and structural parameters of Small Magellanic Cloud star clusters

In this work, we estimate, for the first time, the total masses and mass function (MF) slopes of a sample of 29 young and intermediate-age Small Magellanic Cloud (SMC) clusters from CCD Washington photometry. We also derive age, interstellar reddening and structural parameters for most of the studied clusters by employing a statistical method to remove the unavoidable field star contamination. Only these 29 clusters out of 68 originally analysed cluster candidates present stellar overdensities and coherent distribution in their colour–magnitude diagrams compatible with the existence of a genuine star cluster. We employed simple stellar population models to derive general equations for estimating the cluster mass based only on its age and integrated light in the B, V, I, C and T1 filter. These equations were tested against mass values computed from luminosity functions, showing an excellent agreement. The sample contains clusters with ages between 60 Myr and 3 Gyr and masses between 300 and 3000 M ⊙ distributed between ∼0$$_{.}^{\circ}5 and ∼2° from the SMC optical centre. We determined MF slopes for 24 clusters, of which 19 have slopes compatible with that of Kroupa's initial mass function (α = 2.3 ± 0.7), considering the uncertainties. The remaining clusters – H86-188, H86-190, K47, K63 and NGC 242 – showed flatter MFs. Additionally, only clusters with masses lower than ∼1000 M ⊙ and flatter MF were found within ∼0$ $_{.}^{\circ}6 from the SMC rotational centre.Fil: Maia, F.F.S.. Universidade Federal do Minas Gerais; BrasilFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Santos Jr., João F. C.. Universidade Federal do Minas Gerais; Brasi

Mass distribution and structural parameters of Small Magellanic Cloud star clusters

In this work we estimate, for the first time, the total masses and mass function slopes of a sample of 29 young and intermediate-age SMC clusters from CCD Washington photometry. We also derive age, interstellar reddening and structural parameters for most of the studied clusters by employing a statistical method to remove the unavoidable field star contamination. Only these 29 clusters out of 68 originally analysed cluster candidates present stellar overdensities and coherent distribution in their colour-magnitude diagrams compatible with the existence of a genuine star cluster. We employed simple stellar population models to derive general equations for estimating the cluster mass based only on its age and integrated light in the B, V, I, C and T1 filter. These equations were tested against mass values computed from luminosity functions, showing an excellent agreement. The sample contains clusters with ages between 60 Myr and 3 Gyr and masses between 300 and 3000 Mo distributed between ~0.5 deg. and ~2 deg. from the SMC optical centre. We determined mass function slopes for 24 clusters, of which 19 have slopes compatible with that of Kroupa IMF (2.3 +/- 0.7), considering the uncertainties. The remaining clusters - H86-188, H86-190, K47, K63 and NGC242 - showed flatter MFs. Additionally, only clusters with masses lower than ~1000 Mo and flatter MF were found within ~0.6 deg. from the SMC rotational centre.Comment: 12 pages, 19 figures. Includes another 29 full-page figures of supplementary material. Accepted for publication in the MNRA

The influence of item order of the Household Food Security Survey Module on the assessment of food insecurity in households with children

Abstract Objective: Changes in the item order of the US Household Food Security Survey Module (USHFSSM) were performed throughout time. This study aimed to compare the psychometric properties of the general and specific factors of the 2000 and 2012 versions of the USHFSSM to measure the construct of food insecurity in two Portuguese samples of households with children. Design: Cross-sectional. Setting: Portugal. Participants: An adaptation of the 2000 version was applied to 839 adults (from households with children aged 7-17 years) from the National Food, Nutrition and Physical Activity Survey 2015-2016, while the 2012 version was used among 2855 families from the Generation XXI birth cohort. Results: The 2000 version showed to have a stronger ωh than the 2012 version (0·89 v. 0·78 for the general factor), as well as eigenvalues higher than 1 for the general factor (eigenvalues equal to 9·54, 0·97 and 0·80, for the general factor, specific factor 1 and specific factor 2, respectively), while the 2012 version had also the contribution of specific factors to explain food insecurity (eigenvalues equal to 9·40, 2·40 and 1·20, for general factor and specific factors 1 and 2, respectively). Good internal consistency (ωt = 0·99, for both versions) was obtained. Conclusions: In conclusion, the 2000 and 2012 versions of the USHFSSM showed good psychometric properties; however, the 2000 version has stronger general factor, while the 2012 version also has the contribution of specific factors.

GeMs/GSAOI observations of La Serena 94: an old and far open cluster inside the solar circle

Physical properties were derived for the candidate open cluster La Serena 94, recently unveiled by the VVV collaboration. Thanks to the exquisite angular resolution provided by GeMS/GSAOI, we could characterize this system in detail, for the first time, with deep photometry in JHK$_{s}$ - bands. Decontaminated JHK$_{s}$ diagrams reach about 5 mag below the cluster turnoff in H. The locus of red clump giants in the colour - colour diagram, together with an extinction law, was used to obtain an average extinction of $A_V =14.18 \pm 0.71$. The same stars were considered as standard - candles to derive the cluster distance, $8.5 \pm 1.0$ kpc. Isochrones were matched to the cluster colour - magnitude diagrams to determine its age, $\log{t(yr)}=9.12\pm 0.06$, and metallicity, $Z=0.02\pm0.01$. A core radius of $r_{c}=0.51\pm 0.04$ pc was found by fitting King models to the radial density profile. By adding up the visible stellar mass to an extrapolated mass function, the cluster mass was estimated as $M=(2.65\pm0.57) \times 10^3$ M$_{\odot}$, consistent with an integrated magnitude of $M_{K}=-5.82\pm0.16$ and a tidal radius of $r_{t}=17.2\pm2.1$ pc. The overall characteristics of La Serena 94 confirm that it is an old open cluster located in the Crux spiral arm towards the fourth Galactic quadrant and distant $7.30\pm 0.49$ kpc from the Galactic centre. The cluster distorted structure, mass segregation and age indicate that it is a dynamically evolved stellar system.Comment: 16 pages, 24 figures, 2 Tables, accepted by MNRAS; corrected typo

A construção do pensamento complexo num grupo de pesquisa em educação: primeiros passos

O presente trabalho busca analisar a constituição e dinâmica de dois grupos de pesquisa da UFSCar/CNPq- “Formação de Professores, Ambientalização Curricular e Educação em Ciências” e “Grupo de Estudo e Pesquisa em Educação Científica” - à luz da teoria dos grupos operativos de Pichon-Rivière e da teoria da complexidade. Para isso foram realizadas análises qualitativas das gravações em áudio dos encontros dos grupos e dos resumos das atividades dos mesmos. A partir das análises observaram- se aproximações entre a dinâmica do grupo de pesquisa com algumas características específicasdos grupos operativos na perspectiva Pichoniana. Na relação com o paradigma da complexidade, a principal dificuldade do grupo foi o rompimento com paradigmas anteriores, porém também pode-se observar aproximações e avanços do grupo com a construção do pensamento complexo

Neonatal septic arthritis – A challenging diagnosis

Introdução: O diagnóstico de artrite séptica no recém-nascido é difícil e requer alto grau de suspeição dado que nesta faixa etária a clínica é fruste. Caso clínico: Apresenta-se o caso de um recém-nascido a quem foi diagnosticada paralisia do plexo braquial direito aos 10 dias de vida. Aos 17 dias de vida por limitação da abdução da anca direita levantou-se a suspeita de displasia de desenvolvimento da anca. Foi efetuada ecografia, que corroborou o diagnóstico e o recém-nascido foi encaminhado para consulta de Ortopedia Pediátrica aos 20 dias de vida. Após estudo adequado, concluiu tratar-se de um caso de artrite séptica poliarticular. Atualmente aos oito anos de idade apresenta sequelas no membro superior direito com deformidade e encurtamento do mesmo. Discussão/conclusão: O atraso no diagnóstico e tratamento desta patologia acarreta sequelas futuras que podem ser irreversíveis. Os autores pretendem com a exposição deste caso alertar para a dificuldade e importância do diagnóstico precoce desta patologia

Astrophysical parameters of Small Magellanic Cloud star clusters

We present results obtained from CCD CT1 photometry for a sample of star clusters located in crowded fields in the Small Magellanic Cloud (SMC). The targets were studied by using spatial density maps, center finding algorithms, radial density profiles and a decontamination procedure to clean their color-magnitude diagrams (CMDs) of field stars. The results show that out of 68 objects investigated, only 37 (54 %) present a spatial stellar overdensity. Furthermore, only 8 (12 %) of them show stellar density profiles to be fitted by a King function. Ages, metallicities and color excesses of these genuine clusters were also estimated from isochrone fitting on their field decontaminated CMDs.Fil: Maia, F.. Universidade Federal do Minas Gerais; BrasilFil: Santos Jr., J. F. C.. Universidade Federal do Minas Gerais; BrasilFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

Open Cluster Characterization via Cross-Correlation with Spectral Library

We present a characterization method based on spectral cross-correlation to obtain the physical parameters of the controversial stellar aggregate ESO442-SC04. The data used was obtained with GMOS at Gemini-South telescope including 17 stars in the central region of the ob ject and 6 standard-stars. FXCOR was used in an iterative process to obtain self-consistent radial velocities for the standard-stars and averaged radial velocities for the science spectra. Spectral types, effective temperature, suface gravity and metallicities parameters were determined using FXCOR to correlate cluster spectra with ELODIE spectral library and selecting the best correlation matches using the Tonry and Davis Ratio (TDR). Analysis of the results suggests that the stars in ESO442-SC04 are not bound and therefore they do not constitute a physical system.Comment: 4-page paper from IAU symposium 266. Contains 3 eps figures and IAU document class file 'iau.cls

STEAP2 (six transmembrane epithelial antigen of the prostate 2)

Review on STEAP2 (six transmembrane epithelial antigen of the prostate 2), with data on DNA, on the protein encoded, and where the gene is implicated