In this paper a new least-squares (LS) approach is used to model the discrete-time fractional differintegrator. This approach is based on a mismatch error between the required response and the one obtained by the difference equation defining the auto-regressive, moving-average (ARMA) model. In minimizing the error power we obtain a set of suitable normal equations that allow us to obtain the ARMA parameters. This new LS is then applied to the same examples as in ?R.S. Barbosa, J.A. Tenreiro Machado, I.M. Ferreira, Least-squares design of digital fractional-order operators, FDA'2004 First IFAC Workshop on Fractional Differentiation and Its Applications, Bordeaux, France, July 19-21, 2004, P. Ostalczyk, Fundamental properties of the fractional-order discrete-time integrator, Signal Processing 83 (2003) 2367-2376? so performance comparisons can be drawn. Simulation results show that both magnitude frequency responses are essentially identical. Concerning the modeling stability,both algorithms present similar limitations, although for different ARMA model orders.

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Three-dimensional protein structures of the xanthine oxidase family show different solutions for the problem of transferring electrons between the flavin adenine dinucleotide (FAD) group and the molybdenum cofactor. In xanthine oxidase all the cofactors he within domains of the same protein chain, whereas in CO dehydrogenase the Fe-S centres, FAD and Mo cofactors are enclosed in separate chains and the enzyme exists as a stable complex of all three. In aldehyde oxidore-ductase, only Fe-S and Mo co-factors are present in a single protein chain. Flavodoxin is docked to aldehyde oxidoreductase to mimic the flavin component on the intramolecular electron transfer chain of aanthine oxidase and CO dehydrogenase and, remarkably, the main features of the electron-transfer pathway are observed.

Molybdenum and tungsten are found in biological systems in a mononuclear form in the active site of a diverse group of enzymes that generally catalyze oxygen-atom-transfer reactions. The metal atom (Mo or W) is coordinated to one or two pyranopterin molecules and to a variable number of ligands such as oxygen (oxo, hydroxo, water, serine, aspartic acid), sulfur (cysteines), and selenium (selenocysteines) atoms. In addition, these proteins contain redox cofactors such as iron-sulfur clusters and heme groups. All of these metal cofactors are along an electron-transfer pathway that mediates the electron exchange between substrate and an external electron acceptor (for oxidative reactions) or donor (for reductive reactions). We describe in this Account a combination of structural and electronic paramagnetic resonance studies that were used to reveal distinct aspects of these enzymes.

No abstract is available for this item.

The foresight and scenario building methods can be an interesting reference for social sciences, especially in terms of innovative methods for labour process analysis. A scenario – as a central concept for the prospective analysis – can be considered as a rich and detailed portrait of a plausible future world. It can be a useful tool for policy-makers to grasp problems clearly and comprehensively, and to better pinpoint challenges as well as opportunities in an overall framework. The features of the foresight methods are being used in some labour policy making experiences. Case studies developed in Portugal will be presented, and some conclusions will be drawn in order to organise a set of principles for foresight analysis applied to the European project WORKS on the work organisation re-structuring in the knowledge society, and on the work design methods for new management structures of virtual organisations.

On 19 and 20 October 2006, the Research Centre on Enterprise and Work Organisation (IET) organised the first international conference on “Foresight Studies on Work in the Knowledge Society”. It took place at the auditorium of the new Library of FCT-UNL and had the support of the research project “CodeWork@VO” (financed by FCT-MCTES and co-ordinated by INESC, Porto). The conference related to the European research project “Work Organisation and Restructuring in the Knowledge Society” (WORKS), which is financed by the European Commission. The main objective of the conference was to analyse and discuss research findings on the trends of work structures in the knowledge society, and to debate on new work organisation models and new forms of work supported by ICT.

The paper examines change processes und future perspectives in the knowledge society. It presents the clothing and textile industry as an example for a transforming industry in a global economy. The paper reviews existing future studies, which have surveyed change processes and future developments in the clothing and textile industry. Main goals of the review are the identification of changes in work and the description of the restructuring of global value chains within the clothing and textile sector. The paper also highlights major current trends, drivers of change and future prospects in this sector.

No abstract is available for this item.

The foresight and scenario building methods can be an interesting reference for social sciences, especially in terms of innovative methods for labour process analysis. A scenario – as a central concept for the prospective analysis – can be considered as a rich and detailed portrait of a plausible future world. It can be a useful tool for policy-makers to grasp problems clearly and comprehensively, and to better pinpoint challenges as well as opportunities in an overall framework. The features of the foresight methods are being used in some labour policy making experiences. Case studies developed in Portugal will be presented, and some conclusions will be drawn in order to organise a set of principles for foresight analysis applied to the European project WORKS on the work organisation re-structuring in the knowledge society, and on the work design methods for new management structures of virtual organisations.

On 19 and 20 October 2006, the Research Centre on Enterprise and Work Organisation (IET) organised the first international conference on “Foresight Studies on Work in the Knowledge Society”. It took place at the auditorium of the new Library of FCT-UNL and had the support of the research project “CodeWork@VO” (financed by FCT-MCTES and co-ordinated by INESC, Porto). The conference related to the European research project “Work Organisation and Restructuring in the Knowledge Society” (WORKS), which is financed by the European Commission. The main objective of the conference was to analyse and discuss research findings on the trends of work structures in the knowledge society, and to debate on new work organisation models and new forms of work supported by ICT.

On 19 and 20 October 2006, the Research Centre on Enterprise and Work Organisation (IET) organised the first international conference on “Foresight Studies on Work in the Knowledge Society”. It took place at the auditorium of the new Library of FCT-UNL and had the support of the research project “CodeWork@VO” (financed by FCT-MCTES and co-ordinated by INESC, Porto). The conference related to the European research project “Work Organisation and Restructuring in the Knowledge Society” (WORKS), which is financed by the European Commission. The main objective of the conference was to analyse and discuss research findings on the trends of work structures in the knowledge society, and to debate on new work organisation models and new forms of work supported by ICT.

The relationship between the changes of the global economy and individual working conditions formed the background of the first WORKS conference “The transformation of work in a global knowledge economy: towards a conceptual framework”, held in Chania, Greece from 21st – 22nd September, 2006 and attended by around 50 European researchers. Experts from academia and trade unions from all over the world were invited to give insights into their field of research, contributing to one of the main topics of the conference: (i) globalisation and organisational restructuring, (ii) workers’ organisation, the quality of working life and the gender dimension and (iii) global experiences and recommendations.

The paper will present the central discourse of the knowledge-based society. Already in the 1960s the debate of the industrial society already raised the question whether there can be considered a paradigm shift towards a knowledge-based society. Some prominent authors already foreseen ‘knowledge’ as the main indicator in order to displace ‘labour’ and ‘capital’ as the main driving forces of the capitalistic development. Today on the political level and also in many scientific disciplines the assumption that we are already living in a knowledge-based society seems obvious. Although we still do not have a theory of the knowledge-based society and there still exist a methodological gap about the empirical indicators, the vision of a knowledge-based society determines at least the perception of the Western societies. In a first step the author will pinpoint the assumptions about the knowledge-based society on three levels: on the societal, on the organisational and on the individual level. These assumptions are relied on the following topics: a) The role of the information and communication technologies; b) The dynamic development of globalisation as an ‘evolutionary’ process; c) The increasing importance of knowledge management within organisations; d) The changing role of the state within the economic processes. Not only the differentiation between the levels but also the revision of the assumptions of a knowledge-based society will show that the ‘topics raised in the debates’ cannot be considered as the results of a profound societal paradigm shift. However what seems very impressive is the normative and virtual shift towards a concept of modernity, which strongly focuses on the role of technology as a driving force as well as on the global economic markets, which has to be accepted. Therefore – according to the official debate - the successful adaptation of these processes seems the only way to meet the knowledge-based society. Analysing the societal changes on the

Decameric vanadate species (V10) inhibit the rate and the extent of G-actin polymerization with an IC50 of 68+/-22 microM and 17+/-2 microM, respectively, whilst they induce F-actin depolymerization at a lower extent. On contrary, no effect on actin polymerization and depolymerization was detected for 2mM concentration of "metavanadate" solution that contains ortho and metavanadate species, as observed by combining kinetic with (51)V NMR spectroscopy studies. Although at 25 degrees C, decameric vanadate (10 microM) is unstable in the assay medium, and decomposes following a first-order kinetic, in the presence of G-actin (up to 8 microM), the half-life increases 5-fold (from 5 to 27 h). However, the addition of ATP (0.2mM) in the medium not only prevents the inhibition of G-actin polymerization by V10 but it also decreases the half-life of decomposition of decameric vanadate species from 27 to 10h. Decameric vanadate is also stabilized by the sarcoplasmic reticulum vesicles, which raise the half-life time from 5 to 18h whereas no effects were observed in the presence of phosphatidylcholine liposomes, myosin or G-actin alone. It is proposed that the "decavanadate" interaction with G-actin, favored by the G-actin polymerization, stabilizes decameric vanadate species and induces inhibition of G-actin polymerization. Decameric vanadate stabilization by cytoskeletal and transmembrane proteins can account, at least in part, for decavanadate toxicity reported in the evaluation of vanadium (V) effects in biological systems.

Algunos de los fenómenos donde el concepto de “globalización” es aplicado incluyen la internacionalización de los mercados, la globalización de la cultura, el dominio pol{\'ıtico hegemónico del mundo por algunos estados poderosos, o grupos de estados, el poder creciente de organismos supranacionales, y el desarrollo de una división global de trabajo. De acuerdo con Radice, la globalización é generalmente definida como “un proceso a través de lo cual una proporción creciente de transacciones económicas, sociales e culturales ocurre directamente o indirectamente entre partners de pa{\'ıses distintos” (Radice, 2004: 154). Un ponto de partida para entender la división global del trabajo debe ser la investigación de los modos como las empresas se reestructuran, una vez que son los actores-llave en la decisión sobre que trabajo debe ser encontrado y donde. Las “cadenas de valor” descriven cada etapa en el proceso productivo de un producto o un servicio final. La palabra “valor” en la frase “cadena de valor” dice respecto al valor añadido. Cada etapa en la cadena de valor implica recibir inputs, procesarlos, y entonces pasarlos a la unidad siguiente en la cadena, con el valor que está sendo adicionado no proceso. As unidades separadas da cadena de valor pueden estar dentro da misma empresa (in-house) o en distintas empresas (outsourced). Similarmente pueden estar en un mismo local, o en otra localización. La normalización de muchos procesos del negocio, combinada con la digitalización da información y el desarrollo de redes de telecomunicaciones de elevada capacidad ha tornado posible el trabajo tele-mediado, pudiendo este ser externalizado y/o re-localizado, conduciendo à introducción de una división de trabajo internacional no trabajo de procesamiento de información. Esta comunicación presentará algunos resultados derivados do proyecto europeo WORKS, donde son estudiados casos portugueses de empresas que justamente se integran en

Rapid identification of proteins is of primary importance for the analytical community. Protein-biomarker discovery for medical diagnostics or pharmacological purposes is becoming one of the hottest research topics. Moreover, rapid identification of proteins can help unambiguous bacterial and virus detection. In addition, the fast identification of bacteria can be used to beat bioterrorism. As a consequence, new analytical methodologies have emerged recently with the aim of making protein analysis as fast and as confident as possible. In this article, we critically review the new trends in sample treatment for protein identification and comment on the prospects for the future in this promising analytical area. (c) 2006 Elsevier Ltd. All rights reserved.

Algunos de los fenómenos donde el concepto de “globalización” es aplicado incluyen la internacionalización de los mercados, la globalización de la cultura, el dominio político hegemónico del mundo por algunos estados poderosos, o grupos de estados, el poder creciente de organismos supranacionales, y el desarrollo de una división global de trabajo. De acuerdo con Radice, la globalización é generalmente definida como “un proceso a través de lo cual una proporción creciente de transacciones económicas, sociales e culturales ocurre directamente o indirectamente entre partners de países distintos” (Radice, 2004: 154). Un ponto de partida para entender la división global del trabajo debe ser la investigación de los modos como las empresas se reestructuran, una vez que son los actores-llave en la decisión sobre que trabajo debe ser encontrado y donde. Las “cadenas de valor” descriven cada etapa en el proceso productivo de un producto o un servicio final. La palabra “valor” en la frase “cadena de valor” dice respecto al valor añadido. Cada etapa en la cadena de valor implica recibir inputs, procesarlos, y entonces pasarlos a la unidad siguiente en la cadena, con el valor que está sendo adicionado no proceso. As unidades separadas da cadena de valor pueden estar dentro da misma empresa (in-house) o en distintas empresas (outsourced). Similarmente pueden estar en un mismo local, o en otra localización. La normalización de muchos procesos del negocio, combinada con la digitalización da información y el desarrollo de redes de telecomunicaciones de elevada capacidad ha tornado posible el trabajo tele-mediado, pudiendo este ser externalizado y/o re-localizado, conduciendo à introducción de una división de trabajo internacional no trabajo de procesamiento de información. Esta comunicación presentará algunos resultados derivados do proyecto europeo WORKS, donde son estudiados casos portugueses de empresas que justamente se integran en cadenas de valor globalizadas, sendo analizadas

Algunos de los fenómenos donde el concepto de “globalización” es aplicado incluyen la internacionalización de los mercados, la globalización de la cultura, el dominio político hegemónico del mundo por algunos estados poderosos, o grupos de estados, el poder creciente de organismos supranacionales, y el desarrollo de una división global de trabajo. De acuerdo con Radice, la globalización é generalmente definida como “un proceso a través de lo cual una proporción creciente de transacciones económicas, sociales e culturales ocurre directamente o indirectamente entre partners de países distintos” (Radice, 2004: 154). Un ponto de partida para entender la división global del trabajo debe ser la investigación de los modos como las empresas se reestructuran, una vez que son los actores-llave en la decisión sobre que trabajo debe ser encontrado y donde. Las “cadenas de valor” descriven cada etapa en el proceso productivo de un producto o un servicio final. La palabra “valor” en la frase “cadena de valor” dice respecto al valor añadido. Cada etapa en la cadena de valor implica recibir inputs, procesarlos, y entonces pasarlos a la unidad siguiente en la cadena, con el valor que está sendo adicionado no proceso. As unidades separadas da cadena de valor pueden estar dentro da misma empresa (in-house) o en distintas empresas (outsourced). Similarmente pueden estar en un mismo local, o en otra localización. La normalización de muchos procesos del negocio, combinada con la digitalización da información y el desarrollo de redes de telecomunicaciones de elevada capacidad ha tornado posible el trabajo tele-mediado, pudiendo este ser externalizado y/o re-localizado, conduciendo à introducción de una división de trabajo internacional no trabajo de procesamiento de información. Esta comunicación presentará algunos resultados derivados do proyecto europeo WORKS, donde son estudiados casos portugueses de empresas que justamente se integran en cadenas de valor globalizadas, sendo analizadas

Nitrogen is a vital component in living organisms as it participates in the making of essential biomolecules such as proteins, nucleic acids, etc. In the biosphere, nitrogen cycles between the oxidation states +V and -III producing many species that constitute the biogeochemical cycle of nitrogen. All reductive branches of this cycle involve the conversion of nitrate to nitrite, which is catalyzed by the enzyme nitrate reductase. The characterization of nitrate reductases from prokaryotic organisms has allowed us to gain considerable information on the molecular basis of nitrate reduction. Prokaryotic nitrate reductases are mononuclear Mo-containing enzymes sub-grouped as respiratory nitrate reductases, periplasmic nitrate reductases and assimilatory nitrate reductases. We review here the biological and molecular properties of these three enzymes along with their gene organization and expression, which are necessary to understand the biological processes involved in nitrate reduction.

This report begins with some general information and analysis of policy and regulation that were the subjects of discussion and exchange in the policy pillar in the first phase of WORKS. The second section is a synthesis of country information on general principles and trends of policy and policy enforcement. This is followed by a summary of sector information for the sectors chosen by the qualitative pillar to be the objects of empirical analysis. The last summarises research questions and dimensions to be guidelines for carrying out case studies and capturing the relevance and effects of policy and institutions at the workplace. –

Fractional centred differences and derivatives definitions are proposed, generalizing to real orders the existing ones valid for even and odd positive integer orders. For each one, suitable integral formulations are obtained. The computations of the involved integrals lead to new generalizations of the Cauchy integral derivative. To compute this integral, a special two-straight-line path was used. With this the referred integrals lead to the well-known Riesz potential operators and their inverses that emerge as true fractional centred derivatives, but that can be computed through summations similar to the well-known Grünwald-Letnikov derivatives.

This report begins with some general information and analysis of policy and regulation that were the subjects of discussion and exchange in the policy pillar in the first phase of WORKS. The second section is a synthesis of country information on general principles and trends of policy and policy enforcement. This is followed by a summary of sector information for the sectors chosen by the qualitative pillar to be the objects of empirical analysis. The last summarises research questions and dimensions to be guidelines for carrying out case studies and capturing the relevance and effects of policy and institutions at the workplace.

In this work we present a kinetic study of the superoxide-mediated electron transfer reactions between rubredoxin-type proteins and members of the three different classes of superoxide reductases (SORs). SORs from the sulfate-reducing bacteria Desulfovibrio vulgaris (Dv) and D. gigas (Dg) were chosen as prototypes of classes I and II, respectively, while SOR from the syphilis spirochete Treponema pallidum (Tp) was representative of class III. Our results show evidence for different behaviors of SORs toward electron acceptance, with a trend to specificity for the electron donor and acceptor from the same organism. Comparison of the different kapp values, 176.9+/-25.0 min(-1) in the case of the Tp/Tp electron transfer, 31.8+/-3.6 min(-1) for the Dg/Dg electron transfer, and 6.9+/-1.3 min(-1) for Dv/Dv, could suggest an adaptation of the superoxide-mediated electron transfer efficiency to various environmental conditions. We also demonstrate that, in Dg, another iron-sulfur protein, a desulforedoxin, is able to transfer electrons to SOR more efficiently than rubredoxin, with a kapp value of 108.8+/-12.0 min(-1), and was then assigned as the potential physiological electron donor in this organism.