Subelliptic Li-Yau estimates on three dimensional model spaces

We describe three elementary models in three dimensional subelliptic geometry which correspond to the three models of the Riemannian geometry (spheres, Euclidean spaces and Hyperbolic spaces) which are respectively the SU(2), Heisenberg and SL(2) groups. On those models, we prove parabolic Li-Yau inequalities on positive solutions of the heat equation. We use for that the $\Gamma_{2}$ techniques that we adapt to those elementary model spaces. The important feature developed here is that although the usual notion of Ricci curvature is meaningless (or more precisely leads to bounds of the form $-\infty$ for the Ricci curvature), we describe a parameter $\rho$ which plays the same role as the lower bound on the Ricci curvature, and from which one deduces the same kind of results as one does in Riemannian geometry, like heat kernel upper bounds, Sobolev inequalities and diameter estimates

Utilisation de la PCR-RFLP sur de l'ADN chloro-plastique pour l'étude des relations phylogénétiques au sein du genre Phaseolus

Phylogenetic relationships among 74 accessions belonging to six species of Phaseolus are investigated using variation in chloroplast DNA assessed according to a PCR-RFLP protocol. Three fragments of chloroplast DNA are amplified using universal primers, and then digested with 10 restriction enzymes. Thirty-six haplotypes are identified on the basis of the polymorphism in fragment number and size. Three main phylogenetic groups, strongly supported through bootstrap analysis, are identified: (1) accessions from Phaseolus lunatus and Phaseolus xolocotzii; (2) accessions from Phaseolus glabellus; (3) accessions from Phaseolus vulgaris, Phaseolus polyanthus and Phaseolus coccineus. Within the third group, accessions of Phaseolus coccineus are scattered along the phylogenetic tree, which provides some evidence that coccineus accessions are paraphyletic with respect to Phaseolus vulgaris and Phaseolus polyanthus. An analysis of molecular variance applied on four species show that they are significantly differentiated with 79% of molecular variance among species and 21% within species. The results agree with previous investigations on chloroplast DNA variation in the genus Phaseolus, and suggest that PCRRFLP methods, which are technically less labour-intensive than previous methods, are of great value for phylogenetic investigations at the generic level

Effect of floral debris removal from fruit clusters on botrytis bunch rot of Chardonnay grapes

The relationship between senescent floral debris retained in fruit clusters and the incidence and severity of botrytis bunch rot was examined in Chardonnay grapevines over three seasons. Floral debris was removed from clusters at either early or late fruit set using compressed air or a back-pack leaf blower. Additional treatments were included to determine if a commercial sticker spray adjuvant (Nu-Film 17) increased debris retention in clusters. Physical removal of floral debris generally reduced botrytis bunch rot; however, reductions in botrytis bunch rot were only significant in some vineyards. The sticker spray adjuvant had no effect on retention of debris or on botrytis bunch rot. The incidence and severity of botrytis bunch rot were not affected by timing of debris removal, but late removal by compressed air, when berries were as much as 8 mm in diameter, did cause berry bruising. The data demonstrate that senescent floral debris and aborted berries can contribute to increased botrytis bunch rot, and that practical measures to reduce debris retention may aid disease control

The subelliptic heat kernel on SU(2): Representations, Asymptotics and Gradient bounds

The Lie group SU(2) endowed with its canonical subriemannian structure appears as a three-dimensional model of a positively curved subelliptic space. The goal of this work is to study the subelliptic heat kernel on it and some related functional inequalities.Comment: Update: Added section + Correction of typo

Epidermal growth factor receptor subunit locations determined in hydrated cells with environmental scanning electron microscopy

Imaging single epidermal growth factor receptors (EGFR) in intact cells is presently limited by the available microscopy methods. Environmental scanning electron microscopy (ESEM) of whole cells in hydrated state in combination with specific labeling with gold nanoparticles was used to localize activated EGFRs in the plasma membranes of COS7 and A549 cells. The use of a scanning transmission electron microscopy (STEM) detector yielded a spatial resolution of 3 nm, sufficient to identify the locations of individual EGFR dimer subunits. The sizes and distribution of dimers and higher order clusters of EGFRs were determined. The distance between labels bound to dimers amounted to 19 nm, consistent with a molecular model. A fraction of the EGFRs was found in higher order clusters with sizes ranging from 32–56 nm. ESEM can be used for quantitative whole cell screening studies of membrane receptors, and for the study of nanoparticle-cell interactions in general

Curvature-dimension inequalities and Li-Yau inequalities in sub-Riemannian spaces

In this paper we present a survey of the joint program with Fabrice Baudoin originated with the paper \cite{BG1}, and continued with the works \cite{BG2}, \cite{BBG}, \cite{BG3} and \cite{BBGM}, joint with Baudoin, Michel Bonnefont and Isidro Munive.Comment: arXiv admin note: substantial text overlap with arXiv:1101.359

Malliavin calculus for fractional heat equation

In this article, we give some existence and smoothness results for the law of the solution to a stochastic heat equation driven by a finite dimensional fractional Brownian motion with Hurst parameter $H>1/2$. Our results rely on recent tools of Young integration for convolutional integrals combined with stochastic analysis methods for the study of laws of random variables defined on a Wiener space.Comment: Dedicated to David Nualart on occasion of his 60th birthda

Catalogue des objets d'art et de bel ameublement du XVIIIe siècle : estampes, aquarelles, dessins, gouaches, livres illustrés, tableaux et pastels anciens et modernes, sculptures du XVIIIe siècle ... objets de vitrine ... sièges et meubles en bois sculpté ... composant la collection de feu Alfred Sussmann et dont la vente ... Galerie Georges Petit ... les jeudi 18 et vendredi 19 mai 1922 ... ; commissaires-priseurs, F. Lair-Dubreuil, Henri Baudoin ; experts ... Marius Paulme, Georges B. Lasquin, André Schoeller ..

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201