Blind MD-MC Component Separation for Polarized Observations of the CMB with the EM Algorithm

We present the PolEMICA [Aumont & Macias-Perez 2007] (Polarized Expectation-Maximization Independent Component Analysis) algorithm which is an extension to polarization of the SMICA [Delabrouille et al. 2003] temperature component separation method. This algorithm allows us to estimate blindly in harmonic space multiple physical components from multi-detectors polarized sky maps. Assuming a linear noisy mixture of components we are able to reconstruct jointly the electromagnetic spectra of the components for each mode T, E and B, as well as the temperature and polarization spatial power spectra, TT, EE, BB, TE, TB and EB for each of the physical components and for the noise on each of the detectors. This has been tested using full sky simulations of the Planck satellite polarized channels for a 14-months nominal mission assuming a simple linear sky model including CMB, and optionally Galactic synchrotron and dust emissions.Comment: 4 pages, 1 figure, published in the proceedings of the XLIth Rencontres de Morion

La mort de Dante

L'histoire que pratique Jean-Luc Godard dans ses Histoire(s) du cinéma (1986-1997) est une histoire philosophique où la Raison est synonyme de chaos, de perte et d'éloignement de l'Esprit. Au fil des épisodes, la perte devient celle de l'enfance de l'art cinématographique. L'histoire du cinéma apparaît, à l'historien philosophe et cinéaste, comme l'histoire d'une perte de l'Art, mais d'une perte paradoxale, puisqu'elle se décrit aussi comme l'histoire d'une « fin » à l'Art.This history practiced by Jean-Luc Godard in his Histoire(s) du cinéma (1986-1997) is a philosophical history in which Reason is synonymous with chaos, loss and the distancing of the spirit. Through the episodes, the loss portrayed is that of the infancy of cinematographic art. Film history appears, for this philosophical and film-making historian, as a history of the loss of Art, a paradoxical loss, since it describes itself also as the history of an "end" to Art

Un film peut-il être un acte de théorie ?

Il ne manque pas d’exemples historiques de films qui ont été des manifestes ou des gestes critiques, et ce, dès les années 1920. L’auteur du présent article se demande, de manière consciemment provocante, si un film peut aller jusqu’à théoriser. Des travaux récents ont insisté sur la capacité des images à être un véhicule, voire un site de la pensée, mais la théorie est une activité spécifique de l’esprit humain qui semble ne pouvoir se passer du recours au langage verbal. Un film ne peut donc prétendre à la théorisation que lato sensu — mais en rencontrant, tout de même, certaines des valeurs majeures de l’activité théorique en général : la force spéculative, la cohérence, la valeur d’explication. Le plus facile à reconnaître est le rapport entre un film et la cohérence d’un énoncé ; la plupart des films « expérimentaux » radicaux font preuve d’un calcul intensif et précis. Pour ce qui est de la capacité spéculative, l’auteur postule ici qu’elle découle de la reconnaissance, ancienne, de formes non verbales de la pensée ; il ajoute en outre qu’un film ne peut guère spéculer que sur les conditions d’une expérience qui a rapport avec l’expérience filmique. En revanche, le film possède une moindre capacité explicative, limité qu’il est par la nature indirecte de sa réflexion théorique. L’auteur propose enfin quelques conditions selon lesquelles, sans construire une théorie, un film peut être assimilé à un acte théorique (limité) : en restreignant l’objet de sa recherche et de sa réflexion ; en devenant clairement une expérience ; enfin, en exaltant sa capacité poétique et sa capacité d’invention.Since the 1920s, there has been no lack of films which have been manifestos or critical gestures. The author of the present article wonders, in a consciously provocative manner, if a film can go so far as to theorize. Recent work has insisted on the ability of images to be a vehicle or even a site of thought, but theory is a specific activity of the human mind which seems unable to forego the use of verbal language. A film can thus be theoretical only in a broad manner of speaking. Just the same, it shares some of the major qualities of theoretical activity in general: speculative force, coherence, the value of explanation. The easiest to recognize is the relationship between a film and the coherence of an énoncé: most radical “experimental” films demonstrate an intense and precise calculation. As far as speculative ability is concerned, the author suggests that it arises out of the ancient recognition of non-verbal forms of thought; he adds that a film can only speculate about the conditions of an experience related to the film experience. On the other hand, films possess a lesser ability to explain, limited as they are by the indirect nature of their theoretical thinking. To conclude, the author proposes a few conditions under which a film, while not constructing a theory, may be likened to a (limited) theoretical act: by limiting the subject of its research and reflection; by clearly becoming an experience; and finally by exalting its poetic abilities and capacity for invention

The willingness to pay for organic and biodynamic wines in France

Master's thesis in International hotel and tourism management : Culinary leadership and innovationIn recent years, French consumers are increasingly concerned by environmental issues and demanding of eco-friendly products. Thus the market of eco-friendly products in France, including wines, is booming. This quantitative research, based on 172 surveys collected in France, aims to study the willingness of French consumers to pay for organic and biodynamic wines, especially to determine the surplus of price that they would be ready to accept for a wine certified by one of these two labels and to assess the influence of consumers’ socio-demographic and behavioural characteristics on this surplus. The results show that consumers are approximatively ready to pay 1 to 10% more for a biodynamic or an organic wine. For both types of wine labels, the willingness to pay of a consumer is positively correlated to his level of environmental concern, importance of eco-friendly farming, preference for eco-friendly products and perception of organic and biodynamic wines. Consequently, for a French consumer, higher is the level of these variables better will be the willingness to pay. Nonetheless, this willingness to pay for organic and biodynamic wines is not affected by the gender, the perception of ecofriendly products, the knowledge in the field of wines, the frequency of purchase and of consumption of wine, and the knowledge in the field of organic wines

Ocean biogeochemistry exhibits contrasting responses to a large scale reduction in dust deposition

Dust deposition of iron is thought to be an important control on ocean biogeochemistry and air-sea CO<sub>2</sub> exchange. In this study, we examine the impact of a large scale, yet climatically realistic, reduction in the aeolian Fe input during a 240 year transient simulation. In contrast to previous studies, we find that the ocean biogeochemical cycles of carbon and nitrogen are relatively insensitive (globally) to a 60% reduction in Fe input from dust. Net primary productivity (NPP) is reduced in the Fe limited regions, but the excess macronutrients that result are able to fuel additional NPP elsewhere. Overall, NPP and air-sea CO<sub>2</sub> exchange are only reduced by around 3% between 1860 and 2100. While the nitrogen cycle is perturbed more significantly (by ~15%), reduced N<sub>2</sub> fixation is balanced by a concomitant decline in denitrification. Feedbacks between N<sub>2</sub> fixation and denitrification are controlled by variability in surface utilization of inorganic nitrogen and subsurface oxygen consumption, as well as the direct influence of Fe on N<sub>2</sub> fixation. Overall, there is relatively little impact of reduced aeolian Fe input (<4%) on cumulative CO<sub>2</sub> fluxes over 240 years. The lower sensitivity of our model to changes in dust input is primarily due to the more detailed representation of the continental shelf Fe, which was absent in previous models

Early intervention for stuttering: similarities and differences between two programs

In this paper, two proponents of different approaches to early stuttering discuss how they would manage a hypothetical case of stuttering in a preschool-age girl. Two evidence-based approaches are discussed: Palin Parent-Child Interaction Therapy and the Lidcombe Program. This paper arose from an oral discussion session held at the International Fluency Association Conference in Tours, France in 2012