The final step of bacterial denitrification, the two-electron reduction of N2O to N-2, is catalyzed by a multi-copper enzyme named nitrous oxide reductase. The catalytic centre of this enzyme is a tetranuclear copper site called CuZ, unique in biological systems. The in vitro reconstruction of the activity requires a slow activation in the presence of the artificial electron donor, reduced methyl viologen, necessary to reduce CuZ from the resting non-active state (1Cu(II)/3Cu(I)) to the fully reduced state (4Cu(I)), in contrast to the turnover cycle, which is very fast. In the present work, the direct reaction of the activated form of Pseudomonas nautica nitrous oxide reductase with stoichiometric amounts of N2O allowed the identification of a new reactive intermediate of the catalytic centre, CuZA degrees, in the turnover cycle, characterized by an intense absorption band at 680 nm. Moreover, the first mediated electrochemical study of Ps. nautica nitrous oxide reductase with its physiological electron donor, cytochrome c-552, was performed. The intermolecular electron transfer was analysed by cyclic voltammetry, under catalytic conditions, and a second-order rate constant of (5.5 +/- A 0.9) x 10(5) M-1 s(-1) was determined. Both the reaction of stoichiometric amounts of substrate and the electrochemical studies show that the active CuZA degrees species, generated in the absence of reductants, can rearrange to the resting non-active CuZ state. In this light, new aspects of the catalytic and activation/inactivation mechanism of the enzyme are discussed.

Would it be necessary to charge rapidly the electric vehicle (EV) and hybrid electric vehicle (HEV)? It is not easy to answer without a thorough look at the capability of the modern propulsion battery and the power necessities of the EV and HEV. The different possible solutions are compared and maximum speed of charging is analysed. The wired connection for charging is compared to the wireless energy transfer and because of the limitations imposed by the modern and future batteries, the contactless energy transfer is chosen as the future charging method.

TheRuleInterchangeFormatProductionRuleDialect(RIF- PRD) is a W3C Recommendation to define production rules for the Semantic Web, whose semantics is defined operationally via labeled ter- minal transition systems.
In this paper, we introduce a declarative logical characterization of the full default semantics of RIF-PRD based on Answer Set Programming (ASP), including matching, conflict resolution and acting.
Our proposal to the semantics of RIF-PRD enjoys several features. Being based on ASP, it enables a straightforward integration with Logic Programming rule based technology, namely for reasoning and acting with ontologies. Then, its full declarative logical character facilitates the in- vestigation of formal properties of RIF-PRD itself. Furthermore, it turns out that our characterization based on ASP is flexible enough so that new conflict resolution semantics for RIF-PRD can easily be defined and encoded. Finally, it immediately serves as the declarative specification of an implementation, whose prototype we developed.

Recent issues of global heating and energy shortages are imposing a need to change our paradigm around transportation. Somehow, electric vehicles are progressively standing as a strong and necessary alternative for the society. Technically and technologically the acceptance of the EV is easier now than ever but the psychology of the consumers and the running business of internal combustion vehicles, the whole existing infrastructure are too much conservative to be changed easily. The changes in technology require changes in the engineering society and its human resources. The objective of this paper is to give a contribution to the discussion and reflection of potential future scenarios where EV/HEV‘s are spread across the society. It gives an overview of the range of knowledge and competences necessary for a sustainable and streamlined development of those. In fact, it is expected that a new kind of professional profiles need to be created or developed to supply the work market with the right human resources. The paper provides some discussion on the creation of new profiles or adaption of existing ones. Among different possible scenarios the creation of post-graduation courses for students holding undergraduate profiles in the fields referred to earlier would be an interesting and viable solution for fast response. The post graduation would be focused in specific key areas of the EV/HEV. Several factors are pointed out to endorse this scenario

The electromagnetic resonance became irreplaceable tool for wirelessly transfer energy and information. Since long this effect is widely used in communications but recently it is deeply studied and applied at the contactless transfer of energy. The electric/hybrid car battery charging is an urgent need and the knowledge about the resonant contactless transfer became very important. The study of the Series Loaded Series Resonant converter shows it as well suitable for the contactless energy transfer. The idealized Series Resonant Power Converter is used as a base for defining the best (most efficient) modes of operation. Based on the magnetic parameters of the loosely coupled transformer (magnetic link), the characteristics of the contactless power converter are described in approximated form, thus permitting an easier and faster calculation of the converter variables. This is used for instantaneous control of the converter, free from previously known defects.

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Transactional Memory allows programmers to reduce the number of synchronization errors introduced in concurrent programs, but does not ensures its complete elimination. This paper proposes a pattern matching based approach to the static detection of atomicity violation, based on a path-sensitive symbolic execution method to model four anomalies that may affect Transactional Memory programs. The proposed technique may be used to to bring to programmer's attention pairs of transactions that the programmer has mis-specified, and should have been combined into a single transaction. The algorithm first traverses the AST tree, removing all the non-transactional blocks and generating a trace tree in the path sensitive manner for each thread. The trace tree is a Trie like data structure, where each path from root to a leaf is a list of transactions. For each pair of threads, erroneous patterns involving two consecutive transactions are then checked in the trace tree. Results allow to conclude that the proposed technique, although triggering a moderate number of false positives, can be successfully applied to Java programs, correctly identifying the vast majority of the relevant erroneous patterns.

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