The Okamoto-Nolen-Schiffer anomaly without rho-omega mixing

We examine the effect of isospin-violating meson-nucleon coupling constants and of $\pi$-$\eta$ mixing on the binding-energy differences of mirror nuclei in a model that possesses no contribution from $\rho$-$\omega$ mixing. The ${}^{3}$He-${}^{3}$H binding-energy difference is computed in a nonrelativistic approach using a realistic wave function. We find the ${}^{3}$He-${}^{3}$H binding-energy difference very sensitive to the short-distance behavior of the nucleon-nucleon potential. We conclude that for the typically hard Bonn form factors such models can not account for the observed binding-energy difference in the three-nucleon system. For the medium-mass region (A=15--41) the binding-energy differences of mirror nuclei are computed using a relativistic mean-field approximation to the Walecka model. We obtain large binding-energy differences---of the order of several hundred keV---arising from the pseudoscalar sector. Two effects are primarily responsible for this new finding: a) the inclusion of isospin breaking in the pion-nucleon coupling constant, and b) the in-medium enhancement of the small components of the bound-state wave functions. We look for off-shell ambiguities in these results and find them to be large.Comment: 19 LaTeX pages and 2 postscript figures. Revisions/additions: Manuscript now includes a treatment of the binding-energy difference in the three-nucleon system as well as a study of possible off-shell ambiguities in the binding-energy differences of (A=15-41) mirror nucle

Avaliação da liquidez das empresas através da análise da demonstração de fluxos de caixa

Dentre as principais alterações previstas na legislação societária inclui-se a substituição da demonstração das origens e aplicações de recursos pela demonstração de fluxos de caixa (DFC), que apresentam finalidades até certo ponto distintas. Apenas divulgada no país por algumas raras companhias, a DFC permanece pouco explorada no tocante a seu formato de exposição por categorias de atividades, seus métodos de elaboração do fluxo de caixa gerado pelas operações e, principalmente, sua utilização para fins de análise da liquidez das organizações. A utilização de quocientes extraídos de relações entre valores da DFC facilita a interpretação da situação financeira da empresa, sendo o fluxo de caixa operacional a medida absoluta mais relevante mostrada no relatório. Esses índices foram classificados em quatro categorias distintas, cujos propósitos variam da avaliação da capacidade de pagamento do negócio até a determinação das taxas de recuperação (retorno) de caixa. De modo a demonstrar a viabilidade da análise financeira com base na DFC, foram calculados e interpretados os quocientes extraídos dos relatórios publicados pelas empresas - Companhia Vale do Rio Doce (CVRD) e Centrais Elétricas de Minas Gerais S/A (CEMIG), para dois anos consecutivos. Por fim, foram expostas algumas linhas de pesquisa, e ressaltada a questão inerente à classificação dos fluxos de caixa entre as atividades operacionais, de financiamento e de investimento, um problema que os órgãos normativos terão de enfrentar em momento próximo.<br>Among the various changes expected in the upcoming version of the Brazilian corporate law, the substitution of the statement of changes in financial position by the cash flow statement (CFS) stands as one of the most impacting innovations. The CFS is published by few companies in the country and its format, its potential as an instrument for liquidity analysis, as well as possible methods of deriving operating cash flow from it have not been sufficiently explored in the existent literature. The authors propose that the use of ratios obtained from items of the CFS lead to data about financial liquidity, since the operating cash flow is the most important measure of the statement. This study classifies the ratios into four different categories whose purposes vary from determining the business debt payment capacity to the cash return rate. In order to test the CFS financial analysis validity, the authors applied the proposed method to data extracted from CVRD and CEMig reports. Finally, before presenting ideas for future work, this study discusses the issue of classifying cash flow into operating, financing, and investing categories, a problem that accounting committees will face soon