No arbitrage and closure results for trading cones with transaction costs

In this paper, we consider trading with proportional transaction costs as in Schachermayer’s paper (Schachermayer in Math. Finance 14:19–48, 2004). We give a necessary and sufficient condition for ${\mathcal{A}}$ , the cone of claims attainable from zero endowment, to be closed. Then we show how to define a revised set of trading prices in such a way that, firstly, the corresponding cone of claims attainable for zero endowment, ${\tilde{ {\mathcal{A}}}}$ , does obey the fundamental theorem of asset pricing and, secondly, if ${\tilde{ {\mathcal{A}}}}$ is arbitrage-free then it is the closure of ${\mathcal{A}}$ . We then conclude by showing how to represent claims

Design and analysis of cross vaults along history

The history of cross vaults began almost 2,000 years ago with a widespread use during the Middle Ages and Renaissance, becoming nowadays one of the most diffused and fascinating structural typologies of the European building cultural heritage. However, conversely to the undeniable excellence achieved by the ancient masons, the structural behavior of these elements is still at the center of the scientific debate. In this regard, with the aim of reviewing the knowledge on this subject as a concise and valuable support for researchers involved in conservation of historical buildings, with a focus on design rules and structural analysis, the present study firstly introduces the cross vaults from a historical perspective, by describing the evolution of the main geometrical shapes together with basic practical rules used to size them. Then, the article deals with the subsequent advancements in structural analysis methods of vaults, until the development of modern limit analysis.This work was partially carried out under the program "Dipartimento di Protezione Civile - Consorzio RELUIS", signed on 2013-12-27.info:eu-repo/semantics/publishedVersio

Multifonctions s.c.i. et régularisée s.c.i. essentielle

International audienceno abstrac

Short‐term nitrogen‐induced modulation of phospho enol pyruvate carboxylase in tobacco and maize leaves

International audienceUntransformed maize and tobacco plants and tobacco plants constitutively expressing nitrate reductase were grown with sufficient NO−3 to support maximal growth. Four days prior to treatment the tobacco plants were deprived of nitrogen. Excised maize leaves and tobacco leaf discs were fed with either 40 mM KNO 3 or 40 mM KCl (control) in the light. Phospho enol pyruvate (PEP) carboxylase (Case) activity was measured at 0.3 mM and 3 mM PEP. The light‐ induced increase in PEPCase Vmax was greater in maize than tobacco. Furthermore light decreased malate sensitivity in maize (which was N‐replete) but not in N‐deficient tobacco. NO−3 treatment increased PEPCase Vmax values in both species and decreased the sensitivity to inhibition by malate, but effects of NO−3 were much more pronounced in tobacco than maize. PEPCase kinase activity was, however, greater in maize leaves fed NO−3 than in the Cl − ‐treated controls, suggesting that it is responsive to leaf nitrogen supply. A correlation between foliar glutamine content and PEPCase activity was observed. It is concluded that PEPCase is sensitive to N metabolites which favour increased flow through the anapleurotic pathway in both C 3 and C 4 plants