Trivial Witt groups of flag varieties

Let G be a split semi-simple linear algebraic group over a field, let P be a parabolic subgroup and let L be a line bundle on the projective homogeneous variety G/P. We give a simple condition on the class of L in Pic(G/P)/2 in terms of Dynkin diagrams implying that the Witt groups W^i(G/P,L) are zero for all integers i. In particular, if B is a Borel subgroup, then W^i(G/B,L) is zero unless L is trivial in Pic(G/B)/2.Comment: 3 pages, 1 figur

Groupes Classiques

These notes are in french and are an extended version of talks given by the authors at the conference "Schémas en groupes: introduction au séminaire SGA3 de Demazure-Grothendieck" (Luminy, September 2011)We introduce so-called "classical" algebraic group over a general base scheme, and then place them where they belong in the classification of reductive groups established in SGA3

Protéogenèse des graines de soja, Glycine max (L.) Merr. : origine des acides aminés

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Le fait communal en France

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Milnor-Witt Motives

192 pages. This book is composed of updated versions of arXiv:1412.2989, arXiv:1708.06100, arXiv:1710.00594, arXiv:1708.06102, arXiv:1708.06098 and arXiv:1708.06095, together with an introduction, and an indexWe develop the theory of Milnor-Witt motives and motivic cohomology. Compared to Voevodsky's theory of motives and his motivic cohomology, the first difference appears in our definition of Milnor-Witt finite correspondences, where our cycles come equipped with quadratic forms. This yields a weaker notion of transfers and a derived category of motives that is closer to the stable homotopy theory of schemes. We prove a cancellation theorem when tensoring with the Tate object, we compare the diagonal part of our Milnor-Witt motivic cohomology to Minor-Witt K-theory and we provide spectra representing various versions of motivic cohomology in the $\mathbb{A}^1$-derived category or the stable homotopy category of schemes

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Synthesis, Characterisation and Cytotoxic Activity Evaluation of New Metalsalen Complexes Based on the 1,2-bicyclo[2.2.2]octane Bridge

Diaminobicyclo[2.2.2]octane was used as starting material for the preparation, in solution or in a ball-mill, of a salen ligand. Five metal salen complexes were prepared in high yield and their cytotoxic activities were evaluated against HCT116 cell lines. Original manganese salen complex displayed the highest activity with a potency 16 fold higher than the one of cisplatin, demonstrating the benefit of the bridging backbone, compared to other salen systems. An alternative preparation route for this complex by mechanochemistry was also performed.<br /

Synthesis, characterisation and cytotoxic activity evaluation of new metal-salen complexes based on the 1,2-bicyclo[2.2.2]octane bridge

International audience(R)-1,2-Diaminobicyclo[2.2.2]octane was used as a starting material for the preparation, in solution or in a ball mill, of a salen ligand. Five metal salen complexes were prepared in high yield and their cytotoxic activities were evaluated against the Human Colon cancer HCT116 cell lines. The original manganese salen complex displayed the highest activity with a potency 16 fold higher than that of cisplatin, demonstrating the benefit of the bridging backbone compared to other salen systems. An alternative preparation route for this complex by mechanochemistry was also performed