A decomposition theorem for smoothable varieties with trivial canonical class

In this paper we show that any smoothable complex projective variety, smooth in codimension two, with klt singularities and numerically trivial canonical class admits a finite cover, \'etale in codimension one, that decomposes as a product of an abelian variety, and singular analogues of irreducible Calabi-Yau and irreducible symplectic varieties.Comment: 21 page

Long-term risk management of nuclear waste : a real options approach

In this paper, we investigate the optimal timing for deep geological disposal of nuclear waste. Our model is based on the real options approach to investment under uncertainty. In this context, the problem is similar to the optimal exercise policy for a perpetual American spread option. The potential usefulness of such a model for actual decision-making on a sensitive issue is illustrated by some numerical simulations.risk management; optimal stopping; real and American options

Panorama 2006 Des Fondations D'entreprise: Créer Sa Fondation D'entreprise: Quelle Motivations?

This research aims to provide an overview of the motivations for corporations to set up a corporate foundation, also in consideration of the law on the mécénat, the associations and the foundations approved in August 2003

6-O-glucose palmitate synthesis with lipase: Investigation of some key parameters

International audienceFatty acid sugar esters represent an important class of non-ionic bio-based surfactants. They can be synthesized from vinyl fatty acids and sugars with enzyme as a catalyst. Herein, the influence of the solvent, the lipase and the temperature on a model reaction between vinyl palmitate and glucose via enzymatic catalysis has been investigated and the reaction conditions optimized. Full conversion into 6-O-glucose palmitate was reached in 40 h in acetonitrile starting from a reactant ratio 1:1, at only 5%-wt loading of lipase from Candida antarctica B (CALB) without the presence of molecular sieves

Dubresson A. & Raison J.P., L’Afrique subsaharienne. Une géographie du changement

Il s’agit de la deuxième édition, entièrement mise à jour, d’un ouvrage publié en 1998. Comme le livre de Roland Pourtier dont nous avons rendu compte dans un bulletin précédent (Belgeo, 2002/1) et dont le titre est très voisin, il traite de l’Afrique noire en général sans aborder les aspects régionaux tout en rappelant dès l’introduction que l’Afrique est plurielle et en renvoyant pour les données fondamentales sur les milieux et les hommes à L’Afrique de Pierre Gourou (1970) et au volume Le..

Impact of Fatty Acid Structure on CALB‐Catalyzed Esterification of Glucose

International audienceEnzymatic synthesis of fatty acid glucose esters from different fatty acyl donors were performed via enzymatic catalysis in the presence of CALB, using acetonitrile as the solvent. The acyl donor nature (fatty acid or fatty acid vinyl ester) and structure were varied. Lower reaction rates and lower conversions were obtained with fatty acids in comparison to their corresponding vinyl esters. Moreover, the acyl donor with the longest chain length gave the highest conversions. The presence of unsaturation on the acyl donor chain was also shown to be detrimental to the conversion