Topology beyond the horizon: how far can it be probed?

The standard cosmological model does not determine the spatial topology of the universe. This article revisits the signature of a non-trivial topology on the properties of the cosmic microwave background anisotropies. We show that the correlation function of the coefficients of the expansion of the temperature and polarization anisotropies in spherical harmonics, encodes a topological signature that can be used to distinguish a multi-connected space from an infinite space on sizes larger than the last scattering surface. The effect of the instrumental noise and of a galactic cut are estimated. We thus establish boundaries for the size of the biggest torus dintinguisable with temperature and polarization CMB data. We also describe the imprint of the spatial topology on the 3-point function and on non-Gaussianity.Comment: 20 pages, 24 figure

Constraints on mode couplings and modulation of the CMB with WMAP data

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce correlations between multipoles with $\Delta\ell=1$. Applying this estimator, to the V and W bands of the WMAP data, we found a significant detection in the V band. We argue however that foregrounds and in particular point sources are the origin of this signal.Comment: 14 pages, 14 figure

Iatrogenic post-intubation tracheal rupture treated conservatively without intubation: a case report

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Mettre en œuvre un service de questions-réponses en ligne

En quelques années, les bibliothèques françaises ont développé des services de questions-réponses en ligne. Beaucoup d'établissements en sont encore à la phase de réflexion, d'autres démarrent, des réseaux s'élaborent. Dans le contexte actuel du repérage, de la sélection et de la validation de l'information pléthorique disponible sur Internet, les services de questions-réponses en ligne ont un rôle primordial à jouer. En effet, ils valorisent l'offre des bibliothèques dans le contexte du développement des services aux publics et des services à distance. Leur mise en place interroge le professionnel sous de multiples facettes : organisation du travail, politique de services, choix des outils… Ces différents aspects sont abordés, s'appuyant sur des expériences françaises et étrangères, qu'elles soient locales, coopératives et/ou collaboratives. Un éventail d'offres existe aujourd'hui, selon les objectifs, les besoins, les publics, les moyens mis à disposition et les technologies choisies. Le plan s'articule autour de quatre parties pragmatiques et opératoires : construire le projet, développer un savoir-répondre, organiser et travailler au sein d'une équipe et, enfin, adapter le service à l'environnement et à la nature de ses publics. Cet ouvrage collectif, coordonné par Claire Nguyen, se veut un guide utile à tous les professionnels qui veulent créer, maintenir ou faire évoluer un service de questions-réponses à distance

CARACTERISATION DU RECEPTEUR DE LA PROLACTINE CHEZ LA TRUITE ARC-EN-CIEL (ONCORHYNCHUS MYKISS). CLONAGE DE L'ADN COMPLEMENTAIRE CODANT POUR CE RECEPTEUR ET ETUDE DE LA REGULATION DE L'EXPRESSION DU GENE DANS LES ORGANES DE L'OSMOREGULATION

RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF

Transfer of Tilapia (Oreochromis niloticus) to a hyperosmotic environment is associated with sustained expression of prolactin receptor in intestine, gill, and kidney

International audienceExpression of the tilapia prolactin receptor (tiPRL-R) has been characterized in the intestine of Oreochromis niloticus and the levels of both tiPRL-R transcripts and tiPRL binding sites have been further analyzed in this organ, as well as in gill and kidney, during adaptation of tilapia to a hyperosmotic environment. A single high-affinity binding site for tilapia PRL-I (tiPRL-I) was determined in full-length intestine by Scatchard analysis. A heterogeneous distribution of tiPRL-R was detected in this organ, with the posterior part always displaying a higher expression of both tiPRL-R transcript and tiPRL binding sites than the anterior and medial parts. Transfer of tilapia to brackish water (BW) led to an apparent increase in the specific binding of tiPRLs in intestine and gill even for long-term-adapted fish, whereas the high level of kidney tiPRL binding sites measured in control fish reared in fresh water was still detected in BW-adapted tilapia. There was no overall significant modification of tiPRL-R transcript levels in any organ during short-term or long-term adaptation, although a limited decrease occurred in the gill of BW-adapted fish, as shown earlier. Therefore, in O. niloticus adapted to BW, high and sustained levels of ti-PRL-R were observed in the three major osmoregulatory organs, gill, kidney, and intestine