The Determinants of Credit Rating: Brazilian Evidence

This study attempts to identify the determinant factors of credit rating in Brazil. The relevance of this proposal is based on the importance of the subject as well as the uniqueness of the Brazilian market. As for originality, the great majority of previous studies regarding credit rating have been developed in the US, UK and Australia; therefore the effect on other markets is still unclear, especially in emerging markets, like Brazil. We’ve used a Generalized Estimating Equations (GEE) model considering a panel structure with a categorical dependent variable (credit rating) and ten independent variables: leverage, profitability, size, financial coverage, growth, liquidity, corporate governance, control, financial market performance and internationalization. The sample consisted of 153 rating observations during the period of 1997-2011 for a total of 49 public firms operating in the Brazilian Market. Results showed that leverage and internationalization are significant at the 1% level in explaining credit rating. Performance in the financial market was significant at a 5% level; profitability and growth were also statistically significant, but at a 10% significance level

PERFIL E PRODUTIVIDADE CIENTÍFICA DOS DOCENTES DE FINANÇAS VINCULADOS A DOUTORADOS EM ADMINISTRAÇÃO

Este artigo tem como objetivo analisar o perfi l e produtividade científi ca dos professores da área de Finanças vinculados a programas de Doutorado em Administração. Inicialmente, selecionou-se 67 docentes de Finanças vinculados aos 11 cursos de doutorado em Administração com conceito 5 ou 6 na última avaliação da CAPES. Após a exclusão de 13 docentes, chegou-se a um total de 54 Currículos Lattes a serem analisados. Os principais resultados demonstraram que: grande parte dos professores de Finanças é bacharel, mestre e doutor em Administração; apenas três fi zeram doutorado-sanduíche, nove concluíram pós-doutorado, e somente sete possuem bolsa de produtividade do CNPq; 19 atuam na linha de pesquisa ‘Mercado Financeiro e de Capitais’. No que diz respeito à orientação, os docentes contribuíram com a formação de 994 bacharéis, 635 mestres e 51 doutores. Quanto à produtividade científi ca em congressos, 130 artigos foram publicados em eventos ‘Nacional A’ e 319 em eventos ‘Internacional A’. No que se refere à publicação permanente, 198 artigos foram publicados em periódicos ‘Nacional A’, mas apenas quatro estudos foram publicados em periódicos ‘Internacional A’

Continuous auditing: A literature review

Recent fraud scandals involving highly known corporations like Enron, WorldCom, and Xerox have eroded public confidence in financial reporting. At the same time, the auditing profession has suffered a big hit. In this scenario, Continuous Auditing (CA) seems to have emerged as a response to recover the credibility of the auditing profession as well as meeting Sarbanes-Oxley (SOX) requirements. This study, that adopts an exploratory approach, analyzes the existing literature on this topic. First, we address the concepts, models and implications of CA. After, throughout a search on the journals indexed at the CAPES's Basis, a literature review is conducted. A total of 57 articles were selected. We analyze authorship, affiliation, publications, year and type of research of papers that have addressed CA. Findings evidence that most articles addressing CA are non-empirical and adopt a conceptual approach. Also, there is an increasing tendency of continuous auditing studies. Rutgers University seems to be the World's leading research center on CA. This study aims to contribute to the Accounting Science by evidencing possibilities for research and publication in CA

A constitutive law for dense granular flows

A continuum description of granular flows would be of considerable help in predicting natural geophysical hazards or in designing industrial processes. However, the constitutive equations for dry granular flows, which govern how the material moves under shear, are still a matter of debate. One difficulty is that grains can behave like a solid (in a sand pile), a liquid (when poured from a silo) or a gas (when strongly agitated). For the two extreme regimes, constitutive equations have been proposed based on kinetic theory for collisional rapid flows, and soil mechanics for slow plastic flows. However, the intermediate dense regime, where the granular material flows like a liquid, still lacks a unified view and has motivated many studies over the past decade. The main characteristics of granular liquids are: a yield criterion (a critical shear stress below which flow is not possible) and a complex dependence on shear rate when flowing. In this sense, granular matter shares similarities with classical visco-plastic fluids such as Bingham fluids. Here we propose a new constitutive relation for dense granular flows, inspired by this analogy and recent numerical and experimental work. We then test our three-dimensional (3D) model through experiments on granular flows on a pile between rough sidewalls, in which a complex 3D flow pattern develops. We show that, without any fitting parameter, the model gives quantitative predictions for the flow shape and velocity profiles. Our results support the idea that a simple visco-plastic approach can quantitatively capture granular flow properties, and could serve as a basic tool for modelling more complex flows in geophysical or industrial applications.Comment: http://www.nature.com/nature/journal/v441/n7094/abs/nature04801.htm

RELAÇÃO ENTRE O NÍVEL DE DISCLOSURE DO CAPITAL INTELECTUAL E CARACTERÍSTICAS DAS COMPANHIAS LISTADAS NO ÍNDICE BM&FBOVESPA

O presente estudo objetivou identificar a associação entre o nível de disclosure dos elementos componentes do Capital Intelectual (CI) e as características das empresas listadas no Índice BM&FBovespa. A amostra deste estudo foi composta por 54 companhias com maior volume de negociação na Bolsa de Valores de São Paulo (BM&FBovespa). A pesquisa é exploratória e o procedimento de obtenção dos dados foi documental, por meio dos Relatórios da Administração referentes ao exercício de 2009. Para medir o nível de disclosure do capital intelectual utilizou-se a técnica de análise de conteúdo, por meio da análise de sentenças a partir de uma métrica adaptada com base em estudos anteriores. A associação entre o nível de disclosure e as características das empresas, foi por meio da utilização da técnica de Análise de Correspondência (ANACOR), por meio da qual foram testadas três hipóteses formuladas com base nas variáveis: tamanho, rentabilidade e nível de governança corporativa. Os resultados demonstram que o nível de disclosure do capital intelectual possui associação com o tamanho e o nível de rentabilidade das empresas, já a variável governança corporativa não apresentou associação com o nível de disclosure nas empresas verificadas. No que tange ao ramo de atuação, as empresas do setor de Bens Industriais e Utilidade Pública possuem, em média, as melhores práticas de disclosure voluntário das informações acerca do CI

Are larger primates less faunivorous? Consumption of arthropods by Amazonian primates does not fulfil the Jarman-Bell and Kay models

Terrestrial arthropod groups, including insects, spiders, and millipedes, represent an important food resource for primates. However, species consumed and patterns and rates of arthropod-related feeding for most frugivorous primates are still poorly known. We examined stomach contents of 178 Amazonian primate specimens of nine genera and three families obtained from community-based collections voluntarily donated by subsistence hunters. Based on our results, we assessed whether consumption patterns followed the expected negative relationship between arthropod ingestion and body size as postulated in the Jarman-Bell and Kay models. We identified 12 consumed arthropod taxa, including insects (beetles, grasshoppers, ants, flies, caterpillars, praying mantises, and others), spiders and millipedes. Medium and large-bodied primates consumed a greater diversity (measured by Simpson’s diversity index) and richness of arthropods, but differed in terms of composition of taxa consumed. Cacajao, Sapajus and Cebus consumed proportionally more Orthoptera and Coleoptera compared to the other primate genera analyzed. We did not find significant correlations between richness and diversity of arthropods consumed and primate body mass. There was a slight tendency for the decrease in the relative content of arthropods in the diet with increased body mass in medium and large primates, which does not provide full support for the Jarman-Bell and Kay models. The study of arthropod consumption by arboreal primates in the wild remains challenging. Our study suggests that arthropods supply essential nutrients for frugivorous primates, and provides an alternative method to analyse faunal consumption patterns in primates

High order structure preserving explicit methods for solving linear-quadratic optimal control problems

[EN] We consider the numerical integration of linear-quadratic optimal control problems. This problem requires the solution of a boundary value problem: a non-autonomous matrix Riccati differential equation (RDE) with final conditions coupled with the state vector equation with initial conditions. The RDE has positive definite matrix solution and to numerically preserve this qualitative property we propose first to integrate this equation backward in time with a sufficiently accurate scheme. Then, this problem turns into an initial value problem, and we analyse splitting and Magnus integrators for the forward time integration which preserve the positive definite matrix solutions for the RDE. Duplicating the time as two new coordinates and using appropriate splitting methods, high order methods preserving the desired property can be obtained. The schemes make sequential computations and do not require the storrage of intermediate results, so the storage requirements are minimal. The proposed methods are also adapted for solving linear-quadratic N-player differential games. The performance of the splitting methods can be considerably improved if the system is a perturbation of an exactly solvable problem and the system is properly split. Some numerical examples illustrate the performance of the proposed methods.The author wishes to thank the University of California San Diego for its hospitality where part of this work was done. He also acknowledges the support of the Ministerio de Ciencia e Innovacion (Spain) under the coordinated project MTM2010-18246-C03. The author also acknowledges the suggestions by the referees to improve the presentation of this work.Blanes Zamora, S. (2015). High order structure preserving explicit methods for solving linear-quadratic optimal control problems. 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A structured registration program can be validly used for quality assessment in general practice

ABSTRACT: BACKGROUND: Patient information, medical history, clinical outcomes and demographic information, can be registered in different ways in registration programs. For evaluation of diabetes care, data can easily be extracted from a structured registration program (SRP). The usability of data from this source depends on the agreement of this data with that of the usual data registration in the electronic medical record (EMR). Aim of the study was to determine the comparability of data from an EMR and from an SRP, to determine whether the use of SRP data for quality assessment is justified in general practice. METHODS: We obtained 196 records of diabetes mellitus patients in a sample of general practices in the Netherlands. We compared the agreement between the two programs in terms of laboratory and non-laboratory parameters. Agreement was determined by defining accordance between the programs in absent and present registrations, accordance between values of registrations, and whether the differences found in values were also a clinically relevant difference. RESULTS: No differences were found in the occurrence of registration (absent/present) in the SRP and EMR for all the laboratory parameters. Smoking behaviour, weight and eye examination were registered significantly more often in the SRP than in the EMR. In the EMR, blood pressure was registered significantly more often than in the SRP. Data registered in the EMR and in the SRP had a similar clinical meaning for all parameters (laboratory and non-laboratory). CONCLUSIONS: Laboratory parameters showed good agreement and non-laboratory acceptable agreement of the SRP with the EMR. Data from a structured registration program can be used validly for research purposes and quality assessment in general practice

Location of Immunization and Interferon-γ Are Central to Induction of Salivary Gland Dysfunction in Ro60 Peptide Immunized Model of Sjögren's Syndrome

INTRODUCTION: Anti-Ro antibodies can be found in the serum of the majority of patients with Sjögren's syndrome (SS). Immunization with a 60-kDa Ro peptide has been shown to induce SS-like symptoms in mice. The aim of this study was to investigate factors involved in salivary gland (SG) dysfunction after immunization and to test whether the induction of SS could be improved. METHODS: Ro60 peptide immunization was tested in Balb/c mice, multiple antigenic peptide (MAP)-Ro60 and Pertussis toxin (PTX) were tested in SJL/J mice. In addition, two injection sites were compared in these two strains: the abdominal area and the tailbase. Each group of mice was tested for a loss of SG function, SG lymphocytic infiltration, anti-Ro and anti-La antibody formation, and cytokine production in cultured cells or homogenized SG extracts. RESULTS: Ro60 peptide immunization in the abdominal area of female Balb/c mice led to impaired SG function, which corresponded with increased Th1 cytokines (IFN-γ and IL-12) systemically and locally in the SG. Moreover, changing the immunization conditions to MAP-Ro60 in the abdominal area, and to lesser extend in the tailbase, also led to impaired SG function in SJL/J mice. As was seen in the Balb/c mice, increased IFN-γ in the SG draining lymph nodes accompanied the SG dysfunction. However, no correlation was observed with anti-MAP-Ro60 antibody titers, and there was no additional effect on disease onset or severity. CONCLUSIONS: Effective induction of salivary gland dysfunction after Ro60 peptide immunization depended on the site of injection. Disease induction was not affected by changing the immunization conditions. However, of interest is that the mechanism of action of Ro60 peptide immunization appears to involve an increase in Th1 cytokines, resulting in the induction of SG dysfunction