Active site engineering for heterogeneous catalysis using emerging nano-structured materials

The growing concern about the depletion of oil has spurred worldwide interest in finding alternative feedstocks for important petrochemical commodities and fuels. On the one hand, the enormous re-serves found (208 trillion cubic feet proven1), environmental sustainability and lower overall costs point to natural gas as the primary source for energy and chemicals in the near future.2 Nowadays the transformation of methane into useful chemicals and liquid fuels is only feasible via synthesis gas, a mixture of molecular hydrogen and carbon monoxide, that is further transformed to methanol or to hydrocarbons under moderate reaction conditions (150-350 °C and 10-100 bar).3 For a major cost reduction and in order to valorize small natural gas sources, either more efficient "syngas to products" catalysts should be produced or the manner in which methane is initially activated should be changed, ideally by developing catalysts able to directly oxidize methane to interesting products such as methanol. On the other hand, from the point of view of CO2 emissions, the use of the re-maining fossil resources will further contribute to global warming. In this scenario, the development of efficient routes for the transformation of CO2 into useful chemicals and fuels would represent a considerable step forward towards sustainability. Indeed, the environmental and economic incen-tives to develop processes for the conversion of CO2 into fuels and chemicals are great. However, for such conversions to become economically feasible, considerable research is necessary. In this lecture we will summarize our recent efforts into the design of new catalytic systems, based on MOFs and COFs, to address these challenges. Examples include the development of new Fe based FTS catalysts, electrocatalysts for the selective conversion of CO2 into syngas, the development of efficient catalysts for the utilization of formic acid as hydrogen storage vector and the development of new enzyme inspired systems for the direct transformation of methane to methanol under mild reaction conditions. References (1) http://www.clearonmoney.com/dw/doku.php?id=public:natural_gas_reserves. (2) Derouane, E. G.; Parmon, V.; Lemos, F.; Ribeiro, F. R. Sustainable Strategies for the Up-grading of Natural Gas: Fundamentals, Challenges, and Opportunities; Springer, 2005. (3) Rofer-DePoorter, C. K. Chemical Reviews. ACS Publications 1981, pp 447–474.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Synthesis of a simple self-stabilizing system

With the increasing importance of distributed systems as a computing paradigm, a systematic approach to their design is needed. Although the area of formal verification has made enormous advances towards this goal, the resulting functionalities are limited to detecting problems in a particular design. By means of a classical example, we illustrate a simple template-based approach to computer-aided design of distributed systems based on leveraging the well-known technique of bounded model checking to the synthesis setting.Comment: In Proceedings SYNT 2014, arXiv:1407.493

Flux switching alternators for small wind generation

This paper considers the application of flux switching alternators for small wind generation. First, after a brief presentation of the small wind energy systems, a description and the fundamentals of flux switching machines is given, then the state of art of flux switching generators is presented. Finally a critical assessment is shown, considering the main advantages and drawbacks of this type of machines as alternator for use in small wind generation systems.Peer ReviewedPostprint (published version

The Limitations of Community-Based Tourism as an Instrument of Development Cooperation: the value of the Social Vocation of the Territory concept

This paper contributes to the debate over the validity of community-based tourism (CBT) as a development and poverty-reduction strategy in the rural-peasant world. In this debate, researchers tend to compare and contrast specific experiences on which they have conducted field work. This implies limitations in the analysis: conclusions may be biased, leading to circular unresolved discussions. This paper introduces a structural analysis, to discover whether CBT has intrinsic characteristics which mean that as an instrument of development cooperation it increases the risks typically involved in social intervention. It applies the concept of the Social Vocation of the Territory (SVT), adapted from Land Suitability concepts used in geography and environmental studies. SVT is a historical process in which land and local society adapt over time to reach equilibrium in specific uses of natural and social resources. Employing this concept on South American case studies, this paper concludes that CBT can have limitations as an instrument of development cooperation and poverty reduction, because of increasing peasant differentiation, social unrest, problems with local decision-making, lack of local tourism business knowledge and training, pseudo-participation, and work and time restructuring. Use of the SVT concept can help CBT in certain very specific circumstances

Linking and Weighting Efficiency Estimates with Stock Performance in Banking Firms

The purpose of this paper is to contribute further evidence on bank efficiency by defining alternative measures of costs when estimating efficiency and competitive viability by linking the results of efficiency estimates to market returns of financial institutions. Given a series of functions (production costs, opportunity costs of capital with systematic risk, opportunity cost of capital with specific risk, and branch network distribution), we estimate alternative partial measures of bank efficiency with DEA. Assuming that these functions are related to market returns on shares, an estimation of the relative importance of each of the functions is carried out, considering an additional initially unknown function which can be attributed to individual differences not accounted for in the previous four definitions. Due to the nature of the model, strong collinearity may be expected among efficiency measures. With the aid of a tabu search procedure, artificial instrumental variables are generated which avoid collinearity and permit the isolation of the underlying relationships. Results are applied to all Spanish banks quoting on the stock exchange.

Unification and Matching on Compressed Terms

Term unification plays an important role in many areas of computer science, especially in those related to logic. The universal mechanism of grammar-based compression for terms, in particular the so-called Singleton Tree Grammars (STG), have recently drawn considerable attention. Using STGs, terms of exponential size and height can be represented in linear space. Furthermore, the term representation by directed acyclic graphs (dags) can be efficiently simulated. The present paper is the result of an investigation on term unification and matching when the terms given as input are represented using different compression mechanisms for terms such as dags and Singleton Tree Grammars. We describe a polynomial time algorithm for context matching with dags, when the number of different context variables is fixed for the problem. For the same problem, NP-completeness is obtained when the terms are represented using the more general formalism of Singleton Tree Grammars. For first-order unification and matching polynomial time algorithms are presented, each of them improving previous results for those problems.Comment: This paper is posted at the Computing Research Repository (CoRR) as part of the process of submission to the journal ACM Transactions on Computational Logic (TOCL)

Perfecto Gascón Bardají, un metge aragonès a l'Espluga de Francolí (1924-1955)

Perfecto Gascón Bardají, un metge aragonès a l'Espluga de Francolí (1924-1955

Tourism, real estate development and depeasantisation in Latin America

[eng] Residential tourism transforms societies and rural economies. Among other changes, it converts agrarian land into urbanized land, and brings new agents into the land market (real estate investors, clients acquiring second homes, etc.). These two factors imply an increase in land prices that is often behind the crisis of traditional agrarian activities and stimulates the emigration of the local population. The present article examines how this process takes place. Is it simply a mechanism of supply and demand? Or are other economic and political factors at work? To understand this phenomenon, we analyze three South American cases in which residential tourism is in different stages of development.[spa] El turismo residencial transforma las sociedades y economías rurales. Entre otros cambios, convierte la tierra de vocación agraria en suelo urbanizable, e incorpora en el mercado de tierras a nuevos agentes (inversores inmobiliarios, clientes que adquieren la residencia, etc.). Estos dos factores comportan un incremento del precio del suelo que muchas veces impulsa la crisis de las actividades agrarias tradicionales y estimula la emigración de la población local. El presente texto examina cómo tiene lugar este proceso. ¿Es el simple mecanismo de la oferta y la demanda? ¿O actúan también otros factores económicos y políticos? Para ello, se analizan tres casos sudamericanos, uno en Brasil y dos en Ecuador, en los que el turismo residencial se encuentra en diferentes fases de desarroll

Lie symmetries of systems of second-order linear ordinary differential equations with constant coefficients

Lie symmetries of systems of second-order linear ordinary differential equations with constant coefficients are exhaustively described over both the complex and real fields. The exact lower and upper bounds for the dimensions of the maximal Lie invariance algebras possessed by such systems are obtained using an effective algebraic approach

Ataque epileptiforme idiopático y síncope cardiogénico en el perro : consideraciones diagnósticas

Con este trabajo intentamos aporrar algunas consideraciones prácticas sobre la problemática de trastornos convulsivos en el perro y del diagnóstico del ataque epiléptico idiopático y síncope cardiogénico en la especie animal. Para ello presentamos 8 casos clínicos de animales llevados a la consulta de nuestro departamento y que, en algún momento, presentan lo que los propietarios denominaron como «ataques». En estos animales, además del estudio cardiogénico se realizaron análisis de calcio, fósforo, glucosa, recuentos de glóbulos totales, fórmula leucocitaria y proteínograma, cuyos resultados son discutidos en cada caso. Asimismo resaltamos la importancia de la anamnesis en el diagnóstico de estos procesos y proponemos el protocolo a seguir en estas situaciones.This paper attempts to provide some practical considerations on tbe problems of convulsive disorders in dogs and on the diagnosis of idiopathic epilep tic attacks and cardiogenic syncope in animals. With this ainm eight cases of animals brought to the surgery in our department, who at one stage bad suffered «attacks» according to their owners, are presented. All the animals undervient a cardiogenic study as well as analyses including calcium, phosphorus, blood glucose, blood counts and differential, and a proteinogram, the results of which are discussed for each case. Likewise, the importance of the anamnesis is emphasized to reach a diagnosis of these disorders and a protocol is proposed for such situations