Fitting isochrones to open cluster photometric data III. Estimating metallicities from UBV photometry

The metallicity is a critical parameter that affects the correct determination fundamental characteristics stellar cluster and has important implications in Galactic and Stellar evolution research. Fewer than 10 % of the 2174 currently catalog open clusters have their metallicity determined in the literature. In this work we present a method for estimating the metallicity of open clusters via non-subjective isochrone fitting using the cross-entropy global optimization algorithm applied to UBV photometric data. The free parameters distance, reddening, age, and metallicity simultaneously determined by the fitting method. The fitting procedure uses weights for the observational data based on the estimation of membership likelihood for each star, which considers the observational magnitude limit, the density profile of stars as a function of radius from the center of the cluster, and the density of stars in multi-dimensional magnitude space. We present results of [Fe/H] for nine well-studied open clusters based on 15 distinct UBV data sets. The [Fe/H] values obtained in the ten cases for which spectroscopic determinations were available in the literature agree, indicating that our method provides a good alternative to determining [Fe/H] by using an objective isochrone fitting. Our results show that the typical precision is about 0.1 dex

Micro-firms way to succeed: How owners manage people

This study explores the configurations of people management practices in micro-firms and their relation with entrepreneurial orientation and firm performance in a four-year window. Based on the ability-, motivation- and opportunity-focused practices framework, we identify configurations of HRM practices used in micro-firms and, in conjugation with entrepreneurial orientation, how they affect employee growth and net income. We analyzed data collected from 114 micro-firm owners combined with firm objective performance measures using Multiple Correspondence Analysis and Cluster Analysis. Results show a taxonomy of three configurations of HRM practices associated with different entrepreneurial orientation strategic postures in micro-firms: “Financial centric HRM practices”, “Operations centric HRM practices”, and “People centric HRM practices”. We assume that configurational methods can help uncover the complexity of the interplay between HRM practices and strategic postures on micro-firm performance. This study contributes to the literature in micro-firms by revealing effective people-related managerial practices on performance.info:eu-repo/semantics/publishedVersio

Complex Network Tools to Understand the Behavior of Criminality in Urban Areas

Complex networks are nowadays employed in several applications. Modeling urban street networks is one of them, and in particular to analyze criminal aspects of a city. Several research groups have focused on such application, but until now, there is a lack of a well-defined methodology for employing complex networks in a whole crime analysis process, i.e. from data preparation to a deep analysis of criminal communities. Furthermore, the "toolset" available for those works is not complete enough, also lacking techniques to maintain up-to-date, complete crime datasets and proper assessment measures. In this sense, we propose a threefold methodology for employing complex networks in the detection of highly criminal areas within a city. Our methodology comprises three tasks: (i) Mapping of Urban Crimes; (ii) Criminal Community Identification; and (iii) Crime Analysis. Moreover, it provides a proper set of assessment measures for analyzing intrinsic criminality of communities, especially when considering different crime types. We show our methodology by applying it to a real crime dataset from the city of San Francisco - CA, USA. The results confirm its effectiveness to identify and analyze high criminality areas within a city. Hence, our contributions provide a basis for further developments on complex networks applied to crime analysis.Comment: 7 pages, 2 figures, 14th International Conference on Information Technology : New Generation

Barriers to early identification of autism in Brazil

Objective: Parents of children with autism spectrum disorders (ASD) seem to perceive that their child's development is not following the normal pattern as early as the first year of life. However, ASD children may not receive a diagnosis until they are of preschool age, especially in low- and middle-income countries. The objective of this study was to evaluate the pathway between initial parental concerns about atypical child development and ASD diagnosis in Brazil. Methods: Nineteen mothers whose children had been diagnosed with ASD participated and were interviewed. The ASD group consisted of two girls and 17 boys, with a mean age of 93.0 months (SD 48.4 monthsrange 39-197 months). Results: Mothers had their first concerns regarding ASD when children were 23.6 +/- 11.6 months old, but formal diagnosis occurred at a mean +/- SD age of 59.6 +/- 40.5 months, corresponding to a 3-year delay. Most mothers felt discouraged to address their concerns due to negative experiences with health professionals. Conclusion: In Brazil, mothers perceived the first signs of ASD in their children at an age similar to that reported in other countries, but the diagnosis of ASD seemed to be delayed. Consistent with the literature, mothers reported negative experiences with health professionals during the pathway to achieving ASD diagnosis.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Univ Fed Sao Paulo UNIFESP, Dept Psiquiatria, Ambulatorio Cognicao Social Marcos Tomanik Mercad, Sao Paulo, SP, BrazilUniv Presbiteriana Mackenzie, Programa Posgrad Disturbios Desenvolvimento, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Psiquiatria, Ambulatorio Cognicao Social Marcos Tomanik Mercad, Sao Paulo, SP, BrazilWeb of Scienc

Chromosomal disorders and male infertility

Male factor infertility is considered a complex disorder with a largely unknown etiology that affects about 7% of men. In general, genetic abnormalities account for 15%-30% of condition and Y chromosome microdeletions are also frequent. The study, based on our casuistic, aimed at contributing to a better understanding of the genetic causes of infertility. A group of 410 idiopathic infertile men with non-obstructive azoospermia, oligozoospermia, or unknown semen quality (based on clinical evaluation and/or sperm counts) was retrospectively selected. Conventional karyotype was performed in all samples; Y microdeletion screen was performed in 247 samples. Forty two abnormal karyotypes (10.2%) were found, indicating an elevated frequency of chromosome abnormalities among the selected infertile men, as compared to that of newborn populations (≈0.4%). This frequency is higher than that reported in most similar studies that pointed to frequencies ranging from 2.2%-14.3%. Klinefelter´s syndrome was the most common chromosome disorder (4.9%). There were 18 cases with 47,XXY karyotype and 2 cases of mosaicism involving lines 47,XXY and 46,XY. Reciprocal translocations were identified in 10 cases (2.4%), particularly in men with unknown semen quality. Overall, reciprocal translocations have been found in approximately 1% of the infertile men and more commonly in azoospermics than in oligozoospermics. However, this type of association was not found in the present study. On the other hand, Y microdeletions were identified in 16/247 cases (6.5%), more frequently in azoospermics (13.3%, corresponding to 8/60 azoospermics). Among these 8 cases, 7 presented deletions at the AZFc region. The marked presence of chromosomal abnormalities and Y microdeletions enphasizes the relevance of studying both factors in infertile men to improve genetic counseling, to allow the development of appropriate therapies, and to expand the knowledge about the ethiology of male infertility

Estabilidade de agregados em sistemas de cultivo da soja em sucessão à Urochloa sp.

O uso da Urochloa sp. como cobertura vegetal do solo na entressafra tem ocasionado o aumento do rendimento da soja em sucessão. O objetivo deste trabalho foi avaliar a estabilidade dos agregados, densidade do solo, porosidade do solo, matéria orgânica do solo e o rendimento da soja em um Latossolo Vermelho sob quatro sistemas de cultivo de entressafra em Rio Verde - GO, dentre os quais dois sistemas incluíram a Urochloa sp. O delineamento foi em blocos ao acaso, com quatro repetições, em parcelas subdivididas 2x4 (as formas de correção do solo parcelada anual e total inicial e os tipos de cobertura de solo Urochloa brizantha, milho + U. ruziziensis, milho solteiro e pousio). A cultura da soja foi implantada em toda a área na safra 2011/2012. Durante a floração da soja realizou-se as amostragens de solo, na profundidade de 0 a 10 cm, para as determinações da estabilidade de agregados em água, densidade do solo, porosidade do solo e matéria orgânica do solo. Ao final do ciclo determinou-se o rendimento dos grãos de soja. O uso de U. brizantha em sucessão à soja, favorece o aumento da agregação entre 4,76 e 2,00 mm e reduz a densidade do solo, na camada de 0 a 10 cm de profundidade, quando comparado com as sucessões com milho + U. ruziziensis, milho solteiro e pousio. Isso provavelmente auxilia no maior rendimento da soja em sucessão à U. brizantha