Chemical Abundances of the S star GZ Peg

The chemical compositions of stars from the Asymptotic Giant Branch are still poorly known due to the low temperatures of their atmospheres and therefore the presence of many molecular transitions hampering the analysis of atomic lines. One way to overcome this difficulty is by the study of lines in regions free from molecular contamination. We have chosen some of those regions to study the chemical abundance of the S-type star GZ Peg. Stellar parameters are derived from spectroscopic analysis and a metallicity of -0.77 dex is found. Chemical abundances of 8 elements are reported and an enhancement of s-process elements is inferred, typical to that of an S-type star.Comment: 5 figures, 3 tables. accepted for publication in the Publications of the Astronomical Society of Australi

Detailed Chemical Abundances of Globular Clusters in Local Group Dwarf Galaxies

We present detailed chemical abundances of Fe, Ca and Ba for 17 globular clusters (GCs) in 5 Local Group dwarf galaxies: NGC 205, NGC 6822, WLM, the SMC and LMC. These abundances are part of a larger sample of over 20 individual elements measured in GCs in these galaxies using a new analysis method for high resolution, integrated light spectra. Our analysis also provides age and stellar population constraints. The existence of GCs in dwarf galaxies with a range of ages implies that there were episodes of rapid star formation throughout the history of these galaxies; the abundance ratios of these clusters suggest that the duration of these burst varied considerably from galaxy to galaxy. We find evolution of Fe, Ca, and Ba with age in the LMC, SMC, and NGC 6822 that is consistent with extended, lower-efficiency SF between bursts, with an increasing contribution of low-metallicity AGB ejecta at late times. Our sample of GCs in NGC 205 and WLM are predominantly old and metal-poor with high [Ca/Fe] ratios, implying that the early history of these galaxies was marked by consistently high SF rates.Comment: 2 pages, To appear in the proceedings of the conference "A Universe of Dwarf Galaxies" (Lyon, June 14-18, 2010

HD 11397 and HD 14282 - Two new barium stars?

We have performed a detailed abundance analysis of the content of s-process elements of two dwarf stars with suspected overabundace of those elements. Such stars belong to a special kinematic sample of the solar neighborhood, with peculiar kinematics and different chemical abundances when compared to "normal" disk stars. We aim to define if those stars can be identified as barium stars, based on their s-process elements abundances, and their classification, i.e., if they share their chemical profile with strong or mild barium stars. We also intend to shed light on the possible origins of the different kinds of barium stars. Spectra have been taken by using the FEROS spectrograph at the 1.52m telescope of ESO, La Silla. Abundances have been derived for 18 elements, by matching the synthetic profile with the observed spectrum. We have found that HD 11397 shows a mild enhancement for most of the s-process elements as well as for some r-process elements. This star seems to share its abundance profile with the mild Ba-stars. Although showing some slight chemical anomalies for Y, Sr, Mo, and Pb, HD 14282 depicts a chemical pattern similar to the normal stars with slight s-process enhancements.Comment: 11 pages, 5 figure

Chemical Abundances in Metal-Rich Bulge-like Stars

We have derived chemical abundances for Ca, Ti, Si, Mg, O, Na, Al, Ni, Co and Cr for a sample of stars with peculiar kinematics and probable origin near the bulge. Our sample stars are in the metallicity range = −0.8 ≤ [Fe/H] ≤ +0.6 dex, and have small pericentric distances, Rp ≤ 3.5 kpc, small scale height, with Zmax +0.3 dex. Compared to bulge stars, such elements are deficient in our sample stas. For the iron-peak elements Cr and Ni we have found a slightly overabundant behavior relative to both thin and thick disks distributions in the metal-poor range, and a smooth decreasing trend for [Cr/Fe] for stars in the supersolar regime. [Co/Fe] ratios track the solar value in the metal-poor range, and show an underabundant behavior relative do thin disk stars for metallicities [Fe/H] > 0.0 de

A comparative study of norms for a 400 picture set between Brazilian and American children

OBJECTIVE: This study compared Brazilian and North American children regarding naming, familiarity and visual complexity of a set of 400 pictures. METHOD: Thirty-six Brazilian children (18 boys) aged 5 to 7 were evaluated. Their characteristics and the study procedure and measures were the same as those employed for the North American population enabling direct comparison of data from the two samples through Spearman rho correlations and Student t tests. RESULTS: Positive significant correlations between overall results of Brazilian and North American children were observed for all measures. Qualitative analysis showed that both groups gave modal names that differed from the intended names for the same 59 pictures. The Brazilian children named 72 pictures differently from the intended names that were correctly named by the North American children, who named 26 pictures differently from the intended names that were correctly named by the Brazilians. CONCLUSION: The 400 picture set was shown to be an adequate tool for use in different cultures. However, it is advisable to avoid pictures that produced naming inconsistencies by the Brazilian and North American children in studies in other cultures with the same age group until specific norms are made available.OBJETIVO: Este estudo comparou os resultados entre crianças brasileiras e americanas quanto àomeação, familiaridade com o conceito representado e complexidade visual de um conjunto de 400 figuras MÉTODO: Foram avaliadas 36 crianças brasileiras (18 meninos) de 5 a 7 anos de idade com características semelhantes às crianças americanas. Os procedimentos e medidas empregados no estudo brasileiro foram os mesmos usados para a população americana permitindo comparação direta dos dados das duas amostras através de correlações rho de Spearman e testes t de Student. RESULTADOS: Foram observadas correlações positivas significativas para todas as medidas entre as amostras brasileira e americana. A análise qualitativa demonstrou que ambos os grupos deram nomes modais que diferem do proposto para 59 figuras. As crianças brasileiras utilizaram nomes que diferem do proposto para 72 figuras nomeadas corretamente pelas americanas. As americanas nomearam diferentemente do nome modal 26 figuras nomeadas corretamente pelas brasileiras. CONCLUSÃO: O conjunto de 400 figuras mostrou-se um instrumento adequado para uso em diferentes culturas. Contudo, é aconselhável evitar o uso de figuras que produziram inconsistência de nomeação nas populações brasileira e norte-americana em estudos em outras culturas com o mesmo grupo etário até que normas específicas estejam disponíveis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo (UNIFESP) Departamento de PsicobiologiaUNIFESP, Depto. de PsicobiologiaSciEL

Conjunto de 400 figuras padronizadas para o português: normas de nomeação, familiaridade e complexidade visual para crianças e adultos

The present article provides normative measures for 400 pictured objects (Cycowicz et al., 1997) viewed by Portuguese speaking Brazilian University students and 5-7 year-old children. Name agreement, familiarity and visual complexity ratings were obtained. These variables have been shown to be important for the selection of adequate stimuli for cognitive studies. Children's name agreement was lower than that of adults. The children also failed to provide adequate modal names for 103 concepts, rated drawings as less familiar and less complex, and chose shorter names for pictures. The differences in ratings between adults and children were higher than those observed in the literature employing smaller picture sets. The pattern of correlations among measures observed in the present study was consistent with previous reports, supporting the usefulness of the 400 picture set as a tool for cognitive research in different cultures and ages.Este artigo fornece dados normativos para o Brasil de um conjunto de 400 figuras de objetos (Cycowicz et al., 1997) avaliados por estudantes universitários e crianças de 5-7 anos. Foram obtidos dados referentes à consistência de nomeação, familiaridade com os objetos representados e complexidade visual dos desenhos. Existem evidências de que essas variáveis são importantes para a adequada seleção de estímulos para estudos cognitivos. A consistência de nomeação das crianças foi menor que a dos adultos. Em relação aos adultos, as crianças não conseguiram nomear adequadamente 103 conceitos, avaliaram os desenhos como sendo menos familiares e menos complexos e escolheram nomes mais curtos para as figuras. As diferenças nas avaliações entre adultos e crianças foram mais altas que as observadas na literatura que envolveu conjuntos menores de desenhos. O padrão de correlações entre medidas observadas no presente trabalho são consistentes com relatos anteriores, o que dá suporte à utilidade desse conjunto de 400 figuras como ferramenta para pesquisas cognitivas em diferentes culturas e faixas etárias.Universidade Federal de São Paulo (UNIFESP) Department of PsychobiologyUNIFESP, Department of PsychobiologySciEL

FEROS Abundance Analysis of 21 Bulgelike SMR Stars

We analyze a sample of 21 super-metal-rich (SMR) stars, using high-resolution échelle spectra obtained with the Fiber-fed Extended Range Optical Spectrograph at the 1.5m ESO telescope. The metallicities are in the range 0.07 ≤ [Fe/H] ≤ 0.45, 3 of them in common with Pompéia et al. (2009). Geneva photometry, astrometric data from Hipparcos, and radial velocities from CORAVEL are available for these stars. The peculiar kinematics suggests the thin disk close to the bulge as the probable birthplace of these stars (Grenon 1999). From Hipparcos data, it appears that the turnoff of this population indicates an age of 10-11 Gyr (Grenon 1999). Detailed analysis of the sample stars is carried out, and atmospheric parameters are derived from spectroscopic and photometric determinations. Oxygen abundances of these stars are derived, and [O/Fe] overabundances up to +0.35 are foun

Word-stem completion: stimuli for use in Brazil

Stem-completion tests are commonly used to assess memory. In Brazil, however, there are no publications that propose adequate stimuli for use in this type of task. Our objective was to select adequate word-stems to maximize memory assessment using this task in Brazil. We obtained chance-completion profiles of 137 word-stems that completed at least 10 common words in Portuguese from Brazil and manipulated factors that could influence memory estimates using these stems. We found that depending on the chance-completion of the most frequently used word to complete a stem it is not possible to show memory effects; that is, completion with familiar stimuli (seen before) is not distinguishable from baseline. Guidelines are proposed for the selection of adequate stems and stimuli to maximize the acquisition of memory estimates using indirect stem-completion tasks.Testes de complementação de letras (em inglês ''stem-completion tests'') são amplamente utilizado na literatura internacional para avaliar memória. Não existem no Brasil, porém, trabalhos que propõem estímulos adequados para uso nesse tipo de teste. O objetivo do presente experimento foi selecionar conjuntos de três letras (tríades) que completam palavras em português do Brasil adequadas para maximizar a verificação de memória. Foram obtidos padrões de complementação ao acaso de 137 tríades que completam pelo menos 10 outras palavras comuns em nosso idioma e manipulados fatores que poderiam influenciar nas estimativas de memória usando essas tríades. Verificou-se que, dependendo da probabilidade de complementação das tríades com a palavra mais freqüentemente utilizada ao acaso, não é possível verificar efeitos de memória; ou seja, a taxa de complementação de estímulos familiares (previamente expostos) não é distinguível da linha de base. Foram propostas diretrizes para a seleção de tríades e estímulos adequados para maximizar a obtenção de índices de memória em testes indiretos de complementação.Universidade Federal de São Paulo (UNIFESP)Universidade Federal de São Paulo (UNIFESP) Instituto Dante PazzaneseUNIFESP, Instituto Dante PazzaneseSciEL