The Invariant Two-Parameter Function of Algebras ψ

At present, the research on invariant functions for algebras is very extended since Hrivnák and Novotný defined in 2007 the invariant functions y and j as a tool to study the Inönü–Wigner contractions (IW-contractions), previously introduced by those authors in 1953. In this paper, we introduce a new invariant two-parameter function of algebras, which we call ¯y, as a tool which makes easier the computations and allows researchers to deal with contractions of algebras. Our study of this new function is mainly focused in Malcev algebras of the type Lie, although it can also be used with any other types of algebras. The main goal of the paper is to prove, by means of this function, that the five-dimensional classical-mechanical model built upon certain types of five-dimensional Lie algebras cannot be obtained as a limit process of a quantum-mechanical model based on a fifth Heisenberg algebra. As an example of other applications of the new function obtained, its computation in the case of the Lie algebra induced by the Lorentz group SO(3, 1) is shown and some open physical problems related to contractions are also formulated.Ministerio de Ciencia e Innovación MTM2013-40455-PMinisterio de Ciencia e Innovación FQM-326 (J.N.-V.)Junta de Andalucía FQM-160 (P.P.-F.

The NADPH-Dependent thioredoxin reductase C-2-Cys peroxiredoxin redox system modulates the activity of thioredoxin x in arabidopsis chloroplasts

The chloroplast redox network is composed of a complex set of thioredoxins (Trxs), reduced by ferredoxin (Fdx) via a Fdx-dependent Trx reductase (FTR), and an NADPH-dependent Trx reductase with a joint Trx domain, NTRC, which efficiently reduces 2-Cys peroxiredoxins (2-Cys Prxs). Recently, it was proposed that the redox balance of 2-Cys Prxs maintains the redox state of f-type Trxs, thus allowing the proper redox regulation of Calvin-Benson cycle enzymes such as fructose 1,6-bisphosphatase (FBPase). Here, we have addressed whether the action of 2-Cys Prxs is also exerted on Trx x. To that end, an Arabidopsis thaliana quadruple mutant, ntrc-trxx-δ "2cp, which is knocked out for NTRC and Trx x, and contains severely decreased levels of 2-Cys Prxs, was generated. In contrast to ntrc-trxx, which showed a severe growth inhibition phenotype and poor photosynthetic performance, the ntrc-trxx-δ "2cp mutant showed a significant recovery of growth rate and photosynthetic efficiency, indicating that the content of 2-Cys Prxs is critical for the performance of plants lacking both NTRC and Trx x. Light-dependent reduction of FBPase was severely impaired in mutant plants lacking NTRC or NTRC plus Trx x, despite the fact that neither NTRC nor Trx x is an effective reductant of this enzyme. However, FBPase reduction was recovered in the ntrc-trxx-δ "2cp mutant. Our results show that the redox balance of 2-Cys Prxs, which is mostly dependent on NTRC, modulates the activity of Trx x in a similar way as f-type Trxs, thus suggesting that the activity of these Trxs is highly interconnected.Ministerio de Economía y Competitividad BIO2017-85195-C2-1-

Los swap deuda-naturaleza : estado del arte

En este trabajo se aborda el análisis de los swaps deuda/naturaleza como una forma de financiar la conservación del medio ambiente y desde aquí apoyar al desarrollo sostenible de un país en vías de desarrollo. Se estudian sus mecanismos básicos, sus tipos, su estructura, algunos ejemplos ilustrativos, y sus posibles problemas. ____________________________________________In this paper, we show the analysis of debt/nature swaps as a way of financing the environment conservation and, hence, to support the sustainable development of a developing country. Its basic mechanisms, types, structure, some interesting examples and potential problems are also studied

INTEGRATION AND COMPETITION IN THE EUROPEAN FINANCIAL MARKETS

Financial integration in Europe should affect the competition between markets and intermediaries and generate a convergence of both interest rates and margins among the different countries. This paper analyses the evolution of the convergence in interest rates and the level of competition and its inequalities among the European banking systems for the period 1993 to 2001. The inequality index used ?the Theil index- allows us to break down the inequalities so that the importance of either a country effect or a specialization effect is quantified. If the former effect dominates it would mean that the national banking markets are segmented as a consequence of the existence of obstacles or barriers to the integration. On the other hand, the dominance of the latter effect would be related to the different level of competition depending on the type of banking specialization. La integración financiera en Europa debe producir efectos sobre la competenciaentre mercados e intermediarios (reducción de precios, costes de intermediación ymárgenes) y generar convergencia en tipos de interés y márgenes entre países. Estetrabajo analiza la evolución de la convergencia en tipos de interés y el nivel decompetencia en los sectores bancarios europeos en el periodo 1993-2001. Además, seestudia el grado de desigualdad de los niveles de competencia mediante la aplicacióndel índice de Theil. Este índice permite la descomposición de la desigualdad de formaque se cuantifica la importancia de tanto efectos país como efectos especialización. Silos primeros dominasen querría decir que los mercados bancarios nacionales estaríansegmentados como consecuencia de la existencia de barreras u obstáculos a laintegración. Por otro lado, si dominasen los efectos especialización, el nivel decompetencia dependería del tipo de especialización bancaria.integración, competencia, mercados financieros europeos. integration, competition, European financial markets

Gaussian Markov Random fields and totally positive matrices

The present paper focuses on the study of the conditions under which the covariance matrix of a multivariate Gaussian distribution is totally positive, paying particular attention to multivariate Gaussian distributions that are Gaussian Markov Random Fields. More specifically, it is proven that, if the graph over which the Gaussian Markov Random Field is defined consists of path graphs and the covariances between adjacent variables on the graph are non-negative, then there always exists a reordering of the variables that renders the resulting covariance matrix totally positive. Moreover, this reordering is identified and some cases for which the conditions for the covariance matrix of a multivariate Gaussian distribution to be totally positive are necessary and sufficient are provided

Retos para la inclusión digital : propuestas de futuro

Los días 22 a 25 de septiembre de 2004 se celebró en Murcia el III Congreso Nacional de Tecnología, Diversidad y Educación (Tecnoneet 2004), un foro de encuentro y discusión de carácter pluridisciplinar y abierto a profesionales, usuarios y familias que trabajan, investigan o utilizan las nuevas tecnologías en el campo de la discapacidad y las necesidades educativas específicas. Con motivo de dicho evento, los Comités Científico y Organizador elaboraron un documento de conclusiones del que ofrecemos un extracto. Se puede consultar íntegro en http://www.tecnoneet.or

Archivología, Bibliografía, Bibliotecología y Ciencia de la Información: representación terminológica en la producción profesional cubana 1905-2008

Presentation of a study linking the theoretical problems of the disciplines involved in the system of informative knowledge that found in the literature, —professional production—, in Cuba context, based on the analysis of categories of terms identifying information disciplines. It is based on a qualitative, historical and documentary research, and quantitative research from a temporary exhibition of Cuban professional production of Informative Literature 1905 to 2008, the results in both sections corroborate the status of Cuba informative phenomenon