2,552 research outputs found

    Disentangling the near infrared continuum spectral components of the inner 500 pc of Mrk 573: two-dimensional maps

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    We present a near infrared study of the spectral components of the continuum in the inner 500×\times500 pc2^2 of the nearby Seyfert galaxy Mrk573 using adaptive optics near-infrared integral field spectroscopy with the instrument NIFS of the Gemini North Telescope at a spatial resolution of \sim50 pc. We performed spectral synthesis using the {\sc starlight} code and constructed maps for the contributions of different age components of the stellar population: young (age100age\leq100 Myr), young-intermediate (100<age700100<age\leq700 Myr), intermediate-old (700700 Myr 22 Gyr) to the near-IR K-band continuum, as well as their contribution to the total stellar mass. We found that the old stellar population is dominant within the inner 250 pc, while the intermediate age components dominate the continuum at larger distances. A young stellar component contributes up to \sim20% within the inner \sim70 pc, while hot dust emission and featureless continuum components are also necessary to fit the nuclear spectrum, contributing up to 20% of the K-band flux there. The radial distribution of the different age components in the inner kiloparsec of Mrk573 is similar to those obtained by our group for the Seyfert galaxies Mrk1066, Mrk1157 and NGC1068 in previous works using a similar methodology. Young stellar populations (\leq100 Myr) are seen in the inner 200-300 pc for all galaxies contributing with \ge20% of the K-band flux, while the near-IR continuum is dominated by the contribution of intermediate-age stars (t=t=100 Myr-2 Gyr) at larger distances. Older stellar populations dominate in the inner 250 pc

    Truncated beta nonlinear regression models for soil-water characteristic curves estimation.

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    We propose an alternative approach for estimating soil-water characteristic curves based on truncated beta nonlinear regression models. Thus, assuming that the response variable follows a truncated beta distribution. Maximum likelihood estimator of the curve parameters are obtained by direct maximization of the likelihood function and diagnostic analysis tools are considered to check for model adequacy under the two considered models. A soil prole from the Buriti Vermelho River Basin database is analyzed using the proposed methodology

    Sample size for family evaluation in potato breeding programs.

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    Clonal families from a broad genetic base population in the Potato Breeding Program at the Universidade Federal de Lavras (UFLA), Brazil, were used in this trials. Twenty-five families were assessed in a 5 x 5 triple lattice design. Each plot consisted of 30 clones distributed in three rows of ten plants. Tuber yield per plant, percentage of large tubers, mean weight of large tubers, mean medium-sized tuber weight and tuber specific gravity were measured. Three hundred experiments were simulated varying the family sizes from three to 90 clones. The coefficients of experimental variation (CVe), the coefficients of genetic variation (CVg), heritabilities for family mean and the CVg/CVe ratio were estimated. Genetic parameters were stabilized with family sizes as small as six clones, depending on the trait. This indicates that the families can be adequately represented by a small sample of clones. Using the maximum curvature method it is possible to conclude that approximately 30 clones would be sufficient to represent each family, even for traits with the highest CVe. The genetic variance within family was greater than the genetic variance among families for all traits, indicating a favorable potential for within family selection. The correlation coefficients of the family means with the 5%, 10%, 15% and 20% best clones from each family, considering the five traits assessed, were always high, meaning that within the best families generally are the best clones

    Validação cruzada da versão portuguesa do Índice de Funcionamento Sexual Feminino

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    Introdução: O constructo de ciclo de resposta sexual constitui um modelo de trabalho essencial no campo do estudo da sexualidade feminina. Objectivo: A presente investigação teve como objectivo proceder à validação cruzada duma versão portuguesa do Índice de Funcionamento Sexual Feminino (FSFI), instrumen¬to multidimensional que avalia as diversas fases associadas ao ciclo de resposta sexual em mulheres. Material e métodos: Recorreu-se a um total de 375 participantes do sexo feminino, sub-divididas em amostra normativa (n = 307) e amostra clínica (n = 68), as quais preenche-ram o questionário com a tradução para português do FSFI. Resultados: Foram demonstradas as principais propriedades psicométricas da validação cruzada do FSFI. Discussão: A estrutura multidimensional original do FSFI foi replicada e obtiveram-se igualmente valores bons a nível de consistência interna, de estabilidade temporal, de validade convergente e divergente e de validade discriminante. Conclusões: As boas propriedades psicométricas encontradas justificam e reforçam a re-comendação de utilização do FSFI na população feminina portuguesa

    Evaluation of laser fluorescence in monitoring non-cavitated caries lesion progression on smooth surfaces in vitro.

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    The aim of this study was to evaluate the performance of a pen-type laser fluorescence (LF) device (LFpen: DIAGNOdent pen) to detect and monitor the progression of caries-like lesions on smooth surfaces. Fifty-two bovine enamel blocks were submitted to three different demineralisation cycles for caries-like lesion induction using Streptococcus mutans, Lactobacillus casei and Actinomyces naeslundii. At baseline and after each cycle, the enamel blocks were analysed under Knoop surface micro-hardness (SMH) and an LFpen. One enamel block after each cycle was randomly chosen for Raman spectroscopy analysis. Cross-sectional micro-hardness (CSMH) was performed at different depths (20, 40, 60, 80 and 100 μm) in 26 enamel blocks after the second cycle and 26 enamel blocks after the third cycle. Average values of SMH (± standard deviation (SD)) were 319.3 (± 21.5), 80.5 (± 31.9), 39.8 (± 12.7), and 29.77 (± 10.34) at baseline and after the first, second and third cycles, respectively. Statistical significant difference was found among all periods (p  0.05). One sample of each cycle was characterised through Raman spectroscopy analysis. It can be concluded that LF was effective in detecting the first demineralisation on enamel; however, the method did not show any effect in monitoring lesion progression after three cycles of in vitro demineralisation
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