Determinação de rating de crédito de empresas brasileiras com a utilização de índices contábeis

Este trabajo tiene dos objetivos diferentes pero complementarios: el primero es averiguar si las agencias de evaluación de crédito son actualmente más severas en los análisis de empresas brasileñas, como se sugiere en algunos estudios efectuados para el mercado estadounidense. El segundo objetivo está relacionado con el desarrollo de una metodología de rating basada en el modelo probit ordenado en panel, que, por medio de la utilización de variables contables e indicadoras (dummies), sea capaz de predecir el nivel de rating para las compañías que no dispongan de ninguna evaluación de crédito. Los resultados no indicaron evidencias de que las agencias de rating han sido más rigurosas en sus análisis de las compañías brasileñas con el tiempo. Eso permitió utilizar una muestra del período de diciembre de 2000 a diciembre de 2005 para la previsión de ratings. Las variables utilidad neta sobre el total de activos (ROA), deuda total sobre el total de activos (DT) y la variable indicadora de presencia en el Índice de la Bolsa de Valores de São Paulo (Bovespa - IBOV) fueron las que, conjuntamente, mejor explicaron los ratings en el modelo propuesto.Este trabalho tem dois objetivos diferentes, mas complementares: o primeiro deles é averiguar se as agências de avaliação de crédito vêm sendo mais severas nas análises de empresas brasileiras ao longo do tempo, conforme sugerido em alguns estudos efetuados para o mercado norte-americano. O segundo objetivo está relacionado ao desenvolvimento de uma metodologia de rating, baseada no modelo probito ordenado em painel, que seja capaz de prever, por meio da utilização de variáveis contábeis e indicadoras (dummies), o nível de rating para as companhias que não possuam avaliação alguma de crédito. Os resultados não apontaram evidências de que as agências de ratings vêm sendo mais rigorosas em suas análises das companhias brasileiras ao longo do tempo. Isso permitiu utilizar amostra do período de dezembro de 2000 a dezembro de 2005 para a previsão de ratings. As variáveis Lucro Líquido sobre o Total de Ativos (ROA), Dívida Total sobre o Total de Ativos (DT) e a variável indicadora de presença no Índice da Bolsa de Valores de São Paulo (Bovespa - IBOV) foram as que, conjuntamente, melhor explicaram os ratings no modelo proposto.This work aims at two different, but complementary, objectives: the first, is checking satisfactorily whether the rating agencies are doing a tight job towards Brazilian Corporations on a time basis; as it has been suggested in some studies carried out in the American Financial Market. The second, is related to the development of a rating methodology based on probit ordered in panel, which, through the accounting ratios employed and dummy variables, is able to foresee a level of rating to any corporation whose evaluation has not been carried out. The results presented here have not shown any clue that rating agencies have been more rigorous in their analysis of Brazilian Corporations through time. Thus, allowing the use of data samples between December 2000 and December 2005 to forecast ratings. Return on assets (ROA), total debts on total assets (DT) along with a dummy variable of Ibovespa presence (IBOV) were the ones which better explain the rating on this proposed model

Improved objective bayesian estimator for a PLP model hierarchically represented subject to competing risks under minimal repair regime

In this paper, we propose a hierarchical statistical model for a single repairable system subject to several failure modes (competing risks). The paper describes how complex engineered systems may be modelled hierarchically by use of Bayesian methods. It is also assumed that repairs are minimal and each failure mode has a power-law intensity. Our proposed model generalizes another one already presented in the literature and continues the study initiated by us in another published paper. Some properties of the new model are discussed. We conduct statistical inference under an objective Bayesian framework. A simulation study is carried out to investigate the efficiency of the proposed methods. Finally, our methodology is illustrated by two practical situations currently addressed in a project under development arising from a partnership between Petrobras and six research institutes

Aspectos anatomopatológicos das neoplasias malignas renais: Anatomopathological aspects of malignant renal neoplasms

As neoplasias renais correspondem ao crescimento exacerbado de células tumorais no interior dos rins, classificadas como benignas ou malignas. Neste estudo será abordado sobre as neoplasias malignas renais, a qual correspondem a maior prevalência e são representadas pelo carcinoma de células renais e o tumor de Wilms, com a finalidade de descrever a respeito dos aspectos anatomopatológicos, disseminando informações para o diagnóstico e manejo precoce. O carcinoma de células renais é mais prevalente no sexo masculino, indivíduos mais velhos, geralmente assintomático, contribuindo para o diagnóstico tardio junto a existência de metástases e terapêutica irresponsiva. Não se trata de uma doença genética, sendo o caráter esporádico o predominante, neste contexto os fatores de risco, sobretudo o tabagismo em seguida de obesidade hemodiálise e doenças genéticas são potenciais desencadeantes da enfermidade. Os exames complementares associado a clínica, junto ao acompanhamento eleva a possibilidade de identificação antes de avanços metastáticos. O tumor de Wilms é típico de crianças, acometendo um ou ambos os rins, normalmente com alguma anomalia genética, sendo os sinais inespecíficos, mas sempre manifestando massa palpável e dor abdominal, a qual os métodos de imagem confirmam o diagnóstico e estimam o prognóstico deste. Neste contexto, elucida-se a transcendência que os aspectos anatomopatológicos das neoplasias malignas renais oferecem para a diagnose precoce, devido a escassez e inespecificidafe das manifestações clínicas. Logo, a junção do perfil de cada neoplasia abordado conduz ao manejo adequado e reduz a incidência de tratamentos agressivos e irresponsivos

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora