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As organizações são concebidas com o enfoque principal na eficiência. As práticas de gestão que adoptam pressupõem, regra geral, a estabilidade do ambiente onde estão inseridas. Por isso, as organizações ficam vulneráveis aos distúrbios a que são sujeitas, e cuja frequência é cada vez maior, o que condiciona a sua eficiência, o seu nível de produtividade e, consequentemente, a sua competitividade. Porque existe uma relação de interdependência mais ou menos definida entre as organizações, a ocorrência de um distúrbio numa delas pode afectar todas as que dela dependem. É, por isso, fundamental que as organizações sejam mais resilientes, isto é, sejam capazes de reagir a um distúrbio inesperado, regressando rapidamente ao estado original ou a um melhor, após a cessação do distúrbio. Neste sentido, uma das acções que pode ser tomada é a definição de planos de mitigação e/ou de contingência. A adequação de planos, de mitigação e/ou de contingência, a implementar quando uma organização está perante um distúrbio, sendo por natureza uma actividade pró-activa, pressupõe a identificação dos distúrbios a que a organização pode ficar sujeita. Atendendo a que os distúrbios podem ter características muito diferentes, no que concerne à frequência de ocorrência, efeito crítico, nível de previsibilidade, área afectada na organização e duração, e podem, ainda, ter origem em fontes diversas, internas ou externas à organização produzidas pelo Homem ou pela Natureza, é fundamental que existam modelos que permitam a sua caracterização e a quantificação do grau de severidade das suas consequências para a organização onde incidem. É possível identificar na bibliografia modelos cujo desenvolvimento está associado aos distúrbios. Contudo, o âmbito em que são desenvolvidos é muito diverso. Nenhum deles, porém, permite caracterizar os distúrbios. O principal objectivo deste artigo é apresentar um modelo conceptual que permita caracterizar os distúrbios e avaliar a severidade dos seus efeitos para a organização onde incidem.

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We study the contribution of the most important processes leading to the creation of excited states of Cl14+ ions from the ground configurations of Cl ions in an Electron Cyclotron Resonance Ion Source (ECRIS), which lead to the emission of K X-ray lines. Theoretical values for inner-shell excitation, K and KL ionization cross-sections, and energies and transition probabilities for the de-excitation processes are calculated in the framework of the Multi-Configuration Dirac-Fock (MCDF) method. With reasonable assumptions about the electron energy distribution, a theoretical K[alpha] X-ray spectrum is obtained, which reproduces closely a recent experimental result.

We study the contribution of the most important processes leading to the creation of excited states of Cl14+ ions from the ground configurations of Cl ions in an Electron Cyclotron Resonance Ion Source (ECRIS), which lead to the emission of K X-ray lines. Theoretical values for inner-shell excitation, K and KL ionization cross-sections, and energies and transition probabilities for the de-excitation processes are calculated in the framework of the Multi-Configuration Dirac-Fock (MCDF) method. With reasonable assumptions about the electron energy distribution, a theoretical K[alpha] X-ray spectrum is obtained, which reproduces closely a recent experimental result.

Adenylate kinase (AK) mediates the reversible transfer of phosphate groups between the adenylate nucleotides and contributes to the maintenance of their constant cellular level, necessary for energy metabolism and nucleic acid synthesis. The AK were purified from crude extracts of two sulfate-reducing bacteria (SRB), Desulfovibrio (D.) gigas NCIB 9332 and Desulfovibrio desulfuricans ATCC 27774, and biochemically and spectroscopically characterised in the native and fully cobalt- or zinc-substituted forms. These are the first reported adenylate kinases that bind either zinc or cobalt and are related to the subgroup of metal-containing AK found, in most cases, in Gram-positive bacteria. The electronic absorption spectrum is consistent with tetrahedral coordinated cobalt, predominantly via sulfur ligands, and is supported by EPR. The involvement of three cysteines in cobalt or zinc coordination was confirmed by chemical methods. Extended X-ray absorption fine structure (EXAFS) indicate that cobalt or zinc are bound by three cysteine residues and one histidine in the metal-binding site of the "LID" domain. The sequence (129)Cys-X-5-His-X-15-Cys-X-2-Cys of the AK from D. gigas is involved in metal coordination and represents a new type of binding motif that differs from other known zinc-binding sites of AK. Cobalt and zinc play a structural role in stabilizing the LID domain. (C) 2008 Elsevier Inc. All rights reserved.

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In this study, changes in the TiO2 (110) work function where followed during Ag deposition in the sub- monolayer regime. Changes in the surface are readily detected as changes in the work function. Significant differences where found in measurements at room temperature and at liquid nitrogen temperature, which can be attributed to differences in the growth mode at those temperatures. The observed work function lowering is evidence of dipole formation by Ag clusters on the TiO2 surface. Since the size and shape of these clusters depend on the surface temperature the differences on the work function variation should be related with the polarization induced by the shape of such clusters.

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{A stochastic variational principle for the (two dimensional) Navier-Stokes equation is established. The velocity field can be considered as a generalized velocity of a diffusion process with values on the volume preserving diffeomorphism group of the underlying manifold. Navier-Stokes equation is reinterpreted as a perturbed equation of geodesics for the L (2) norm. The method described here should hold as well in higher dimensions.}

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This paper explores the designing principles to create resilient Supply Chains ({SC’s)} with the ability to return, rapidly, to the initial stage or to an improved one after a disturbance occurrence. {SC} disturbances and failure modes are identified and discussed. The concept of {SC} resilience is defined and explored; a conceptual {SC} Resilience Index and a {SC} Resilience Indicator are proposed. A framework for the design of resilient {SC’s} is introduced, identifying main {SC} characteristic that can be modified to increase {SC} resilience and to mitigate its vulnerability

In this paper, a research project intituled {“Supply} chain management: design for resilient systems” is presented. The project aim is to develop a Management Support System prototype to help managers to react quickly and efficiently to the effects of disruptions that can occur in supply chain. The research project is presented; including the current state of the art in Supply Chain disruptions, the research project objectives and main tasks. Preliminary research findings are presented and discussed.

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