Chiral Symmetry Breaking in the AdS/CFT Correspondence

We study the SU(3)-invariant relevant deformation of D=4 N=4 SU(N) gauge theory at large N using the AdS/CFT correspondence. At low energies, we obtain a nonsupersymmetric gauge theory with three left-handed quarks in the adjoint of SU(N). In terms of the five dimensional gauged supergravity, there is an unstable critical point in the scalar potential for fluctuations of some fields in a nontrivial representation of the symmetry group SU(3). On the field theory side, this corresponds to dynamical breaking of the SU(3) chiral symmetry down to SO(3). We compute the condensate of the quark bilinear and the two-point correlation function of the spontaneously broken currents from supergravity and find a nonzero `pion' decay constant, f_pi.Comment: 21 pages, 1 figure. LaTeX2e, using utarticle.cls (included). Several clarifications and added references. This is the published version, to appear in JHE

Glucocorticoid receptor gene inactivation in dopamine-innervated areas selectively decreases behavioral responses to amphetamine

Peer reviewedPublisher PD

Decay of solitary waves of fractional Korteweg-de Vries type equations

We study the solitary waves of fractional Korteweg-de Vries type equations, that are related to the 1- dimensional semi-linear fractional equations: |D|αu + u − f (u) = 0, with α ∈ (0, 2), a prescribed coefficient p∗(α), and a non-linearity f (u) = |u|p−1 u for p ∈ (1,p∗(α)), or f (u) = up with an integer p ∈ [2;p∗(α)). Asymptotic developments of order 1 at infinity of solutions are given, as well as second order developments for positive solutions, in terms of the coefficient of dispersion α and of the non-linearity p. The main tools are the kernel formulation introduced by Bona and Li, and an accurate description of the kernel by complex analysis theory.publishedVersio

Simulation study of a heat pump for simultaneous heating and cooling coupled to buildings

International audienceIn several situations, a heat pump for simultaneous heating and cooling (HPS) can be installed advantageously in buildings where simultaneous needs occur. Unlike a reversible heat pump that works alternatively in heating or cooling, a HPS operates under three modes: a heating mode, a cooling mode and a simultaneous mode. In this article, different types of buildings are simulated using Trnsys software to identify their needs for heating, cooling and domestic hot water production (DHW). The introduction of a ratio of simultaneous needs in heating and cooling (RSN) can qualify buildings in relation to the appropriateness of a HPS. Three kinds of buildings are investigated (a low-energy building, an office building and a retail space) under three different climatic conditions in France. As the design of a heat pump is highly dependent on the refrigerant properties, models of small-to-medium HPS using R407C, R290 and HFO1234yf are developed. Results of experimental tests on a 15 kW-heating-capacity HPS working with R407C were used to validate the numerical models of components and global model. Finally, a co-solving technique using two environments (EES and Trnsys) is used to compare the performance of the different refrigerants coupled to the building having the best RSN

Mars 1994/1996: The French navigation tasks

In the fall of 1994, Russia will launch a spacecraft to Mars. France is involved in many scientific experiments which are onboard the spacecraft, as PI or CI. Some days before the Mars orbit insertion maneuver, two small stations and two penetrators will be injected into an entry trajectory. They will carry out for at least six months in situ analysis on the Martian surface. Two years later, a second spacecraft will be launched. It will carry the French balloon and a small rover. The scientific data of these landers will be relayed to earth via the spacecraft. However, during the first 20 days of their mission, Mars Observer will be used. To this end, a Mars balloon relay will be used, which will receive the data from the landers and store them into the memory of the Mars Observer camera. The spacecraft will also be used to localize the landers with the help of relative one-way Doppler measurements. An international cooperative is set up for this process, including JPS, Russian ballistic centers (Babakine, Institute of Applied Mathematics, Moscow Flight Control Center), and CNES Toulouse. Another task dedicated to the space mathematics division of CNES is to support the French scientists to prepare their telecommands and to analyze their telemetry. This second part is integrated into the French ground segment created for the Mars 94/96 mission. This paper describes the method used in CNES for the localization process, the support provided to the scientists, and the links for the data exchange

Transcriptome analysis of Sinorhizobium meliloti during symbiosis

BACKGROUND: Rhizobia induce the formation on specific legumes of new organs, the root nodules, as a result of an elaborated developmental program involving the two partners. In order to contribute to a more global view of the genetics underlying this plant-microbe symbiosis, we have mined the recently determined Sinorhizobium meliloti genome sequence for genes potentially relevant to symbiosis. We describe here the construction and use of dedicated nylon macroarrays to study simultaneously the expression of 200 of these genes in a variety of environmental conditions, pertinent to symbiosis. RESULTS: The expression of 214 S. meliloti genes was monitored under ten environmental conditions, including free-living aerobic and microaerobic conditions, addition of the plant symbiotic elicitor luteolin, and a variety of symbiotic conditions. Five new genes induced by luteolin have been identified as well as nine new genes induced in mature nitrogen-fixing bacteroids. A bacterial and a plant symbiotic mutant affected in nodule development have been found of particular interest to decipher gene expression at the intermediate stage of the symbiotic interaction. S. meliloti gene expression in the cultivated legume Medicago sativa (alfalfa) and the model plant M. truncatula were compared and a small number of differences was found. CONCLUSIONS: In addition to exploring conditions for a genome-wide transcriptome analysis of the model rhizobium S. meliloti, the present work has highlighted the differential expression of several classes of genes during symbiosis. These genes are related to invasion, oxidative stress protection, iron mobilization, and signaling, thus emphasizing possible common mechanisms between symbiosis and pathogenesis

The impact of ingroup favoritism on self-esteem:A normative perspective

The present research examines the impact of ingroup favoritism on self-esteem. According to the self-esteem hypothesis (Abrams &amp; Hogg, 1988), favoring the ingroup over an outgroup should lead to higher self-esteem. However, empirical tests of this hypothesis have revealed mixed results. In light of the heterogeneity of these findings, we investigate the moderating role of ingroup norms regarding intergroup discrimination. According to this normative perspective, we hypothesize that believing one has favored the ingroup increases personal self-esteem to the extent that such behavior is congruent with the ingroup norm. Three studies showed a positive impact of perceived ingroup favoritism (vs. intergroup fairness) on personal self-esteem when the ingroup norm was pro-discriminatory (Studies 1-3). However, this effect disappeared when the pro-discriminatory ingroup norm was attenuated (Study 1), and was even reversed when the ingroup norm was clearly anti-discriminatory (Studies 2-3). Further, this moderation was primarily observed when the ingroup norms were injunctive (rather than descriptive; Study 2), and among participants who highly value conformity (Study 3). These findings are discussed with regard to the classical understanding of the self-esteem hypothesis. (C) 2017 Elsevier Inc. All rights reserved.</p

Global Memory Access Modelling for Efficient Implementation of the LBM on GPUs

International audienceIn this work, we investigate the global memory access mechanism on recent GPUs. For the purpose of this study, we created specific benchmark programs, which allowed us to explore the scheduling of global memory transactions. Thus, we formulate a model capable of estimating the execution time for a large class of applications. Our main goal is to facilitate optimisation of regular data-parallel applications on GPUs. As an example, we finally describe our CUDA implementations of LBM flow solvers on which our model was able to estimate performance with less than 5% relative error

A fully coupled diffusion-reaction scheme for moisture sorptionedesorption in an anhydride-cured epoxy resin

Thermoset materials frequently display non-classical moisture sorption behaviors. In this paper, we investigated this issue from an experimental point of view as well as in terms of modeling the water transport. We used the gravimetric technique to monitor water uptake by epoxy samples, with several thicknesses exposed to different levels of humidity during absorption and desorption tests. Our results revealed that the polymer displays a two-stage behavior with a residual amount of water that is desorbed progressively. We proposed a phenomenological reaction-diffusion scheme to describe this behavior. The model describes water transport as a competition between diffusion and the reaction, during which the local diffusivity and solubility depend on the local advancement of the reaction. We then implemented our model using COMSOL Multiphysics and identified it using a MATLAB-COMSOL optimization tool and the experimental data. We discussed the relation between the hydrophilicity of the product of the reaction and the diffusion behavior. We examined the reaction-induced modification of the water concentration field. It is worth noting that part of the phenomenology can be explained by the presence of hydrolyzable groups