4,075 research outputs found
Recommended from our members
E-voting in Brazil - the risks to democracy
Literature has shown that countries with strong democratic traditions, such as the United States and Canada, are not yet using electronic voting systems intensively, due to the concern for and emphasis on security. It has revealed that there is no such thing as an error-free computer system, let alone an electronic voting system, and that existing technology does not offer the conditions necessary for a reliable, accurate and secure electronic voting system. In this context, then, what are the risks of e-voting to democracy? In what ways, if at all, can more fragile, less mature democracies be buttressed with e-voting systems? As a key component of e-democracy, it seems that e-voting technologies are to become more secure and increasingly reliable in the near future and will indeed be adopted in many countries. In what ways, if at all, will the introduction of such systems increase voter confidence in the political system, promote citizen engagement in political life, and nurture the evolution of democracy? If both e-voting and edemocracy are emerging based on popular demand - that is, as a demand-driven alternative to current processes, then there is no doubt that they are likely to enhance and improve the efficiency of traditional democracy. However, if e-voting technology is being introduced based on a supply-driven fashion - the technology exists therefore it should and must be implemented - then the implications for democracy should be considered. Brazil's introduction of e-voting offers a cautionary tale of supply-driven technological implication. The purpose of this paper is to demonstrate how the introduction of e-voting in Brazil is highly risky to democracy due to the lack of emphasis on security and the lack of a sociallyinformed and socially driven approach to technological innovation. The Brazilian example illustrates the democratic implications of a market-driven approach. The lack of a technology strategy designed to promote and extend democratic principles is not surprising given the closed door, market-based negotiations that led to the adoption of e-voting in Brazil. The promise, and indeed, the imperative of a democratic, voter-centered approach as an alternative for the development of an electronic voting system, is explored in the paper
Composição química e valor nutritivo de alimentos disponíveis na Amazônia para nutrição animal.
bitstream/item/60873/1/CPATU-Doc98.pd
Botanical composition and quality of enriched and traditional pastures in northeastern Pará, Brazil.
Editado por Reinhard lieberei, Helmut Bianchi, Vera Boehm, Christoph Reisdorff
Ligadura de traquéia no período pré-natal ou administração intra-amniótica de surfactante ou dexametasona evitam algumas alterações estruturais nas artérias pulmonares de fetos de coelho com hérnia diafragmática congênita produzida com cirurgia
PURPOSE: Characterization of the structural changes occurring in the pulmonary arteries resulting from surgically produced congenital diaphragmatic hernia in rabbits, with particular emphasis on the preventive effects of prenatal tracheal ligation or administration of intra-amniotic dexamethasone or surfactant. METHODS: Twenty rabbit fetuses underwent surgical creation of a left-sided congenital diaphragmatic hernia on the 24th or 25th gestational day. They were divided according to the following procedures: congenital diaphragmatic hernia (n = 5), congenital diaphragmatic hernia plus tracheal ligation (n = 5), congenital diaphragmatic hernia plus intra-amniotic administration of dexamethasone 0.4 mg (n = 5) or surfactant (Curosurf 40 mg, n = 5). On gestational day 30, all the fetuses were delivered by caesarean section and killed. A control group consisted of five nonoperated fetuses. Histomorphometric analysis of medial thickness, cell nuclei density, and elastic fiber density of pulmonary arterial walls was performed. RESULTS: Arteries with an external diameter >; 100 mum have a decreased medial thickness, lower cell nuclei density, and greater elastic fiber density when compared with arteries with external diameter ; 100 mum. Prenatal treatments with tracheal ligation or intra-amniotic administration of dexamethasone or surfactant prevented these changes. In arteries with external diameterOBJETIVO: Caracterização das alterações estruturais que ocorrem nas artérias pulmonares de fetos de coelho com hérnia diafragmática congênita produzida com cirurgia, com destaque especial aos efeitos preventivos da ligadura de traquéia ou administração intra-amniótica de dexametasona ou surfactante. MÉTODOS: Vinte fetos de coelho foram submetidos a cirurgia para produção de hérnia diafragmática no 24º ou 25º dia de gestação. Os animais foram divididos de acordo com os procedimentos: hérnia diafragmática congênita (n = 5), hérnia diafragmática congênita com ligadura de traquéia (n = 5), hérnia diafragmática congênita com administração intraamniótica de 0,4mg de dexametasona (n = 5) ou surfactante (40mg de Curosurf, n = 5). No 30º dia de gestação, todos os fetos foram retirados por cesariana e mortos. O grupo controle consistiu de 5 fetos normais não operados. Foram realizadas análises histomorfométricas da parede das artérias pulmonares: espessura da camada média, contagem do número de núcleos celulares e densidade de fibras elásticas. RESULTADOS: As artérias com diâmetro externo >; 100 mim apresentaram diminuição da espessura da camada média, menor número de núcleos celulares por micrômetro quadrado e maior densidade de fibras elásticas em comparação com as artérias com diâmetro externo diâmetro externo ; 100 mim. Os métodos terapêuticos, ligadura de traquéia e administração intraamniótica de drogas promoveram reversão destas alterações. Nas artérias com diâmetro extern
Potencial alelopático de forrageiras tropicais: efeitos sobre invasoras de pastagens.
Extratos aquosos de sementes, parte aérea e raízes de três gramíneas e três leguminosas forrageiras foram preparados a uma concentração de 10%, com o objetivo de avaliar os efeitos potencialmente alelopáticos sobre a germinação de sementes e o alongamento da radícula das invasoras de pastagens: desmódio, guanxuma e as sa-pe ix e. A germinação foi monitorada em períodos de dez dias, com contagens diárias e eliminação das sementes germinadas. O alongamento da radícula era medido ao final de um período de dez dias de crescimento. Os efeitos do potencial osmótico foram isolados através de cálculos. As espécies doadoras evidenciaram potencialidades alelopáticas que variou de intensidade em função da especificidade entre espécies doadoras e receptoras. B. brizantha e calopogônio foram as espécies que promoveram as reduções mais intensas sobre a germinação das sementes e o alongamento da radícula das espécies receptoras. A parte aérea das espécies doadoras constituiu-se na principal fonte de substâncias potencialmente alelopáticas, solúveis em água. Independentemen te da espécie doadora, desmódio e guanxuma foram as invasoras que se mostraram mais susceptíveis aos efeitos potencialmente alelopáticos, enquanto o assa-peixe foi a mais tolerante
THE ADO METHOD FOR SOLVING ONE-DIMENSIONAL DEEP-PENETRATION TRANSPORT PROBLEMS
In this work, the Analytical Discrete Ordinate method (ADO method) is used to solve deep-penetration transport problems in one-dimensional Cartesian geometry, subject to isotropic and linear anisotropic scattering effects. The regime is considered permanent, the media are homogeneous, and the fluxes are caused by sources located on the boundaries of the domain. In addition, the energy fluctuations will be considered as not significant, characterizing the phenomena as monoenergetic problems. In order to validate the code, method and provide benchmark results, some test problems will be treated and results will be discussed. In particular, the ADO method generated fairly accurate results when compared to other methods based on SN approaches, at a relatively low computational cost
- …