Search results for "TTR"
showing 10 items of 3945 documents
Building Anosov flows on $3$–manifolds
2014
We prove a result allowing to build (transitive or non-transitive) Anosov flows on 3-manifolds by gluing together filtrating neighborhoods of hyperbolic sets. We give several applications; for example: 1. we build a 3-manifold supporting both of a transitive Anosov vector field and a non-transitive Anosov vector field; 2. for any n, we build a 3-manifold M supporting at least n pairwise different Anosov vector fields; 3. we build transitive attractors with prescribed entrance foliation; in particular, we construct some incoherent transitive attractors; 4. we build a transitive Anosov vector field admitting infinitely many pairwise non-isotopic trans- verse tori.
3-manifolds which are orbit spaces of diffeomorphisms
2008
Abstract In a very general setting, we show that a 3-manifold obtained as the orbit space of the basin of a topological attractor is either S 2 × S 1 or irreducible. We then study in more detail the topology of a class of 3-manifolds which are also orbit spaces and arise as invariants of gradient-like diffeomorphisms (in dimension 3). Up to a finite number of exceptions, which we explicitly describe, all these manifolds are Haken and, by changing the diffeomorphism by a finite power, all the Seifert components of the Jaco–Shalen–Johannson decomposition of these manifolds are made into product circle bundles.
Multidimensionality in host manipulation mimicked by serotonin injection.
2014
Manipulative parasites often alter the phenotype of their hosts along multiple dimensions. ‘Multidimensionality’ in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. We compared multidimensionality in ‘host manipulation’ between two closely related amphipods, Gammarus fossarum and Gammarus pulex, naturally and experimentally infected with Pomphorhynchus laevis (Acanthocephala), respectively. To that end, we calculated in each host–parasite association the effect size of the difference between infected and uninfect…
La Lettre au cinéma
2014
Compte-rendu de lecture
Les mains calleuses pour des lettres nouvelles ? Les écritures ouvrières en France à l’orée du 20e siècle
2017
International audience
Self-polarization of light in optical fibers
2015
The second performs the first experimental demonstration of the polarization domain walls which cancel the effects which degrade the intensity and spectral profile of a telecom signal during propagation. This phenomenon comes from non-linear coupling between the two orthogonal polarization modes of light propagating in a Kerr medium in normal dispersion regime, and causes a modulation in phase opposition of the two modes along the fiber. It is possible to lock two optical pulse trains complementary intensity so that the pulses do not suffer the effects of distortion occurring in the fiber in order to maintain the information to be transmitted. And a distortion-free propagation was achieved …
Sur le rôle des singularités hamiltoniennes dans les systèmes contrôlés : applications en mécanique quantique et en optique non-linéaire.
2012
This thesis has two goals: the first one is to improve the control techniques in quantum mechanics, and more specifically in NMR, by using the tools of geometric optimal control. The second one is the study of the influence of Hamiltonian singularities in controlled systems. The chapter about optimal control study three classical problems of NMR : the inversion problem, the influence of the radiation damping term, and the steady state technique. Then, we apply the geometric optimal control to the problem of the population transfert in a three levels quantum system to recover the STIRAP scheme.The two next chapters study Hamiltonian singularities. We show that they allow to control the polar…
Study of mechanisms of action of an immunotherapy by triacyl lipid A in humans
2013
Immunotherapy acting at the primary tumor site and preventing the development of metastases is one of the strategies for treatment of patients with cancer. To improve the efficiency of the latter, it is necessary to understand how it induces tumor cell death. In the laboratory, it was observed the cure of PROb tumors in rats BDIX by the triacyl lipid A. It has been shown that this effect involved the immune system involving interactions with TLRs present in many tumor cells and innate immunity cells such as neutrophils.In this work, we investigated the possible involvement of neutrophils in the antitumor activity of triacyl lipid A in humans.In a Phase 1 study in patients with refractory so…
Theories and methods to assess the social cost of occupational risk factors in France : application to the case of occupational cancers
2011
The main objective of this thesis is to evaluate the social cost of respiratory cancer attributable to occupational risk factors in France. A summary of the available epidemiological data in the literature is performed. By using the Medline database, a review of the literature restricted to meta-analysis highlights the relative risk data available. The method of Attributable Risks (AR) is mobilized to estimate the numbers of lung, sinonasal and mesothelioma cancer cases caused by asbestos, exhaust fumes from diesel engines, painters, crystalline silica, wood dust and leather dust. We then assess the costs of these cancer cases for the french society using the Cost Of Illness (COI) method. T…
Approche fonctionnelle de la diversité des communautés d’insectes pollinisateurs en milieu agricole
2013
Rapport de stage de Master 1 EcolDur; Les pratiques agriculturales intensives ont conduit à un fort déclin des insectes pollinisateurs en Europe par l’utilisation abusive de pesticides, la fragmentation et la destruction des habitats naturels. Parallèlement, l’effondrement de la diversité des adventices (mauvaises herbes des cultures) observé, se traduit pour les pollinisateurs par une forte diminution de la diversité des ressources florales comme le pollen et le nectar. Le but de cette étude est d’étudier les relations existant entre la diversité fonctionnelle des pollinisateurs et celle des communautés végétales pollinisées en milieu agricole. Cette approche fonctionnelle peut permettre d…