Extended Grassmann and Clifford algebras

This paper is intended to investigate Grassmann and Clifford algebras over Peano spaces, introducing their respective associated extended algebras, and to explore these concepts also from the counterspace viewpoint. The exterior (regressive) algebra is shown to share the exterior (progressive) algebra in the direct sum of chiral and achiral subspaces. The duality between scalars and volume elements, respectively under the progressive and the regressive products is shown to have chirality, in the case when the dimension n of the Peano space is even. In other words, the counterspace volume element is shown to be a scalar or a pseudoscalar, depending on the dimension of the vector space to be respectively odd or even. The de Rham cochain associated with the differential operator is constituted by a sequence of exterior algebra homogeneous subspaces subsequently chiral and achiral. Thus we prove that the exterior algebra over the space and the exterior algebra constructed on the counterspace are only pseudoduals each other, when we introduce chirality. The extended Clifford algebra is introduced in the light of the periodicity theorem of Clifford algebras context, wherein the Clifford and extended Clifford algebras Cl(p,q) can be embedded in Cl(p+1,q+1), which is shown to be exactly the extended Clifford algebra. Clifford algebras are constructed over the counterspace, and the duality between progressive and regressive products is presented using the dual Hodge star operator. The differential and codifferential operators are also defined for the extended exterior algebras from the regressive product viewpoint, and it is shown they uniquely tumble right out progressive and regressive exterior products of 1-forms.Comment: 17 pages, to appear in Adv. Appl. Clifford Algebras 16 (3) (2006

A systematic review of the influence of taxation on corporate capital structure

Purpose: The aim of this paper is a systematic review of the corporate finance literature on tax and capital structure since the complexity of legislation on taxation. It is a challenge for to researchers to understand the influence of this legislation on corporate financing. Approach/Methodology/Design: A systematic review is a useful and important tool to check what has being studied and what are the gaps on the specific subject. Therefore, the study provides an examination of a sample of 33 most cited articles in the period from 2013 to 2017 that have been published in the main international financial journals. It is assumed that this analysis is sufficiently robust to support and contribute to the knowledge gaps identification. Findings: It presents the most relevant papers about the influence of taxes on corporate capital structure, classifies and codifies the various characteristics of these articles, describes the strengths and the weaknesses of the studies in the available literature, and provides an agenda and a research framework to address the key gaps in the current knowledge on the theme. Practical Implications: The study will contribute positively to the understanding of foreign direct investment for the governments, world organizations, academia, companies and investors. Originality/Value: To the best of the authors´ knowledge, this is the first systematic review identifying what is missing in the literature on taxation and capital structure.peer-reviewe

Debt tax benefits in a high tax emerging market : evidence from Brazil

Purpose: This study hypothesizes that tax benefits encourage the use of third-party capital, and seeks to verify whether the tax benefit deriving from debts has a positive effect on Brazilian companies’ capital structure. Approach/Methodology/Design: Data on 259 nonfinancial companies over the period 20082018 are extracted from the Standard & Poor’s Capital IQ database and are analyzed through regression with dynamic data panel. The variables considered as tax benefit proxies are: marginal tax rate, kink, standardized kink and tax payment.The investigations comprise: trade off theory, pecking order theory, information asymmetry, bankruptcy costs and agency theory. Findings: A positive debt effect on capital structure, taxation as providing a systematic incentive for greater leverage, and that, Brazilian companies, despite the country’s heavy tax burden, are not taken full advantage of debt tax benefits. The study offers new evidence as to the speed of adjusting the indebtedness level relating to an optimal capital structure target. Brazilian companies have ground to contract more debt and maximize their tax benefit. Practical Implications: The study will contribute positively to the understanding of influence of high tax emerging market for the government, academia, banks, industry, managers, regulators, investors and other users. Originality/value: This study innovates by using MTR, kink and standardized kink to find debt tax benefits affecting emerging market companies’ capital structure.peer-reviewe

Adaptive SPECT: personalizing medical imaging

We develop modern techniques for image quality evaluation and optimization of imaging systems, and use them to control adaptive SPECT systems. Our results should contribute to the development of more personalized and efficient medical imaging

Giuseppe Gatto, La fiaba di tradizione orale, Colecção "Método", Milão, Edizioni Universitarie di Lettere Economia Diritto, 2006, 230 páginas

O Conto da Tradição Oral concilia com felicidade o cariz didáctico duma introdução aos contos maravilhosos e a seriedade inerente a uma pesquisa aprofundada sobre o assunto. Se, por um lado, Giuseppe Gatto é um especialista que domina convenientemente o campo de estudo dos contos maravilhosos, por outro lado, tem o dom de se colocar do ponto de vista do leigo na matéria. Pode assim conduzir os leitores, mediante uma prosa leve e interessante, num percurso de descoberta, ao mesmo tempo acessível e de qualidade. O livro divide-se em três partes, que, sucessivamente, apresentam os principais traços característicos dos contos; realizam uma introdução ao historial das publicações de contos e dos principais modelos de análise deste género narrativo; e apresentam uma útil selecção de textos clássicos e/ou pouco acessíveis

Mário F. Lages, Vida/morte e diafania do mundo na história da Carochinha: ensaio etnológico, "Estudos e Documentos", 13, Lisboa, Universidade Católica Portuguesa, 2006, 498 pp. ISBN

Este estudo delineia e explora as tramas simbólicas subjacentes à tradição da História da Carochinha em Portugal. Decorre de um projecto de longo fôlego que inclui entrevistas e inquéritos realizados em 1980 e 1981, isto é, vinte e cinco anos antes da publicação dos resultados finais da investigação neste livro de quase quinhentas páginas. O longo labor revela-se na cuidadosa arquitectura da obra, na sua minuciosa recensão e apresentação de fontes, na erudição que ressuma da argumentação e no próprio polimento consciencioso da prosa, o qual torna agradável a tarefa de seguir o autor ao longo de um percurso longo, por vezes sinuoso e, ocasionalmente, obscuro

The girl in red and the wolf: a symbolic reading

Este artigo revisita o problema da famosa peça de vestuário de O Capuchinho Vermelho (AT333). Depois de pôr de parte a afirmação de Delarue de que o chaperon rouge é um traçoacessório, sem relação com o tema, considera-se a relação entre os textos literários e os folclóricos, assim como o ponto sobre a difusão cultural, para sugerir a necessidade de, no campo do folclore, tomar em linha de conta traduções simbólicas. Ao examinar quer os textos literários quer algumas versões orais de “O Capuchinho Vermelho”, assim como dados que estão fora do âmbito dos contos, sugiro que, através dos séculos e dos géneros, existe um modelo simbólico coerente subjacente ao encontro de lobos com meninas de vermelho

BlueLab IoT, a Universal Software Platform for IoT Data Acquisition Devices

Physical devices with different sensors and sampling rates distributed over several unrelated locations need to store their values over time. Applications that need the result of a set of sensors must access their data. A common and simple interface within the physical devices, monitoring stations, to store data on a database is needed; as also a simple and common retrieval interface for any application that only shows the data as it is or processes it into higher levels of significance. BlueLab IoT is a platform with libraries and an interface application to aid that development; a working implementation is provided

Atenção conjunta em crianças surdas: especificidades do desenvolvimento e implicações para as práticas

Pretendemos neste trabalho abordar o desenvolvimento da atenção conjunta no contexto de interacções entre a criança e seus cuidadores pela importância que lhe é atribuída para o desenvolvimento sóciocognitivo e, em particular, o desenvolvimento da linguagem. O interesse por este tema advém também do relativo atraso que a investigação reporta no caso de crianças surdas filhas de pais ouvintes que se associa ao designado fenómeno de atenção dividida (Gallaway, 1998; Lederberg, 1993; Wood, Wood Griffiths, & Howarth, 1986). Por causa deste fenómeno, as crianças surdas têm de aprender a coordenar a sua atenção em relação à pessoa com quem interagem, bem como em relação a objecto ou eventos no seu ambiente. Pelas potenciais implicações para as práticas, analisaremos as estratégias de interacção usadas por mães surdas que, com mais facilidade do que mães ouvintes, andaimam o desenvolvimento das capacidades de coordenação da atenção visual das crianças e facilitam a ocorrência de episódios de atenção conjunta e a influencia que os resultados destas investigações têm tido em programas de intervenção precoce direccionados para o apoio a crianças surdas e suas famílias

Fairy-tale enchantments

More than two decades ago the folklorist Isabel Cardigos remarked that the hinge of fairy tales is the cyclical movement in and out of enchantment. I feel that this insight is important, and I propose to briefly explain my understanding of it. First, I mention the importance of using allomotifs to bring out the folk metaphors in fairy tales. Then, I discuss a basic symbolic pa﬒ern of enchantments at the core of fairy tales. Overall, I add to Vladimir Propp’s statement that the most complete fairy tale is a heroic quest the proposition that the irreducible core of fairy tales hinges on feminine maturation. Along the way, I discuss some metaphors suggestive of the lunar template at the core of fairy tales.info:eu-repo/semantics/publishedVersio