Le décret loi du 10 septembre 1926. La mort administrative de l’arrondissement de Puget-Théniers

Toute réforme administrative peut être considérée comme un événement, c’est-à-dire un ensemble de faits significatifs ou notables, pour les contemporains mais aussi pour les analystes qui en ont bâti la discipline de l’histoire de l’Administration. Les réformes de l’administration territoriale ont un impact naturel sur les populations concernées et la discipline relativement récente de la géographie administrative tente d’appréhender ces événements. Ils sont souvent de portée locale : que ce ..

Probing symmetries of quantum many-body systems through gap ratio statistics

The statistics of gap ratios between consecutive energy levels is a widely used tool, in particular in the context of many-body physics, to distinguish between chaotic and integrable systems, described respectively by Gaussian ensembles of random matrices and Poisson statistics. In this work we extend the study of the gap ratio distribution $P(r)$ to the case where discrete symmetries are present. This is important, since in certain situations it may be very impractical, or impossible, to split the model into symmetry sectors, let alone in cases where the symmetry is not known in the first place. Starting from the known expressions for surmises in the Gaussian ensembles, we derive analytical surmises for random matrices comprised of several independent blocks. We check our formulae against simulations from large random matrices, showing excellent agreement. We then present a large set of applications in many-body physics, ranging from quantum clock models and anyonic chains to periodically-driven spin systems. In all these models the existence of a (sometimes hidden) symmetry can be diagnosed through the study of the spectral gap ratios, and our approach furnishes an efficient way to characterize the number and size of independent symmetry subspaces. We finally discuss the relevance of our analysis for existing results in the literature, as well as point out possible future applications and extensions.Comment: 22 pages, 7 figures, Mathematica notebook as electronic supplementary file (enclosed in source file

A first comparison of Cosmo-Skymed and TerraSAR-X data over Chamonix Mont-Blanc test-site

International audienceThis paper presents the first results obtained with satellite im- age time series (SITS) acquired by Cosmo-SkyMed (CSK) over the Chamonix Mont-Blanc test-site. A CSK SITS made of 39 images is merged with a TerraSAR-X SITS made of 26 images by using the orbital information and co-registration tools developed in the EFIDIR project. The results are illus- trated by the computation of speckle-free images by temporal averaging, by the generation and comparison of topographic interferograms and by the measure of glacier displacement fields by amplitude correlation

Androgen-dependent stimulation of brain dopaminergic systems in the female European eel (Anguilla anguilla).

Dopamine (DA), a neurotransmitter present in all vertebrates, is involved in processes such as motor function, learning and behavior, sensory activities, and neuroendocrine control of pituitary hormone release. In the female eel, we analyzed how gonadal steroids regulate brain expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in the biosynthesis of DA. TH mRNA levels were assayed by quantitative real-time RT-PCR. TH-positive nuclei were also localized by in situ hybridization (ISH) and immunohistochemistry, and the location of TH nuclei that project to the pituitary was determined using 1,1'-dioctadecyl-3,3,3',3'-tetramethylindicarbocyanine perchlorate retrograde tracing. Chronic in vivo treatment with testosterone increased TH mRNA specifically in the periglomerular area of the olfactory bulbs and in the nucleus preopticus anteroventralis (NPOav). NPOav was labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindicarbocyanine perchlorate, showing that this nucleus is hypophysiotropic in the eel. The nonaromatizable 5alpha-dihydrotestosterone gave identical results in both areas, whereas 17beta-estradiol had no stimulatory effect, showing that the observed stimulatory effects of testosterone were androgen dependent. In teleosts, DA neurons originating from the NPOav directly inhibit gonadotropic function, and our results indicate an androgen-dependent, positive feedback on this neuroendocrine control in the eel. In mammals, DA interneurons in the olfactory bulbs are involved in the enhancement of olfactory sensitivity and discrimination. Our results in the European eel suggest an androgen-dependent stimulation of olfactory processing, a sensory function believed to be important in eel navigation during its reproductive migration toward the oceanic spawning grounds. To our knowledge, this is the first evidence from any vertebrate of an androgen-dependent effect on DAergic activity in the olfactory bulbs, providing a new basis for understanding the regulation by gonadal steroids of central DAergic systems in vertebrates

Magnetism in reduced dimensions

We propose a short overview of a few selected issues of magnetism in reduced dimensions, which are the most relevant to set the background for more specialized contributions to the present Special Issue. Magnetic anisotropy in reduced dimensions is discussed, on a theoretical basis, then with experimental reports and views from surface to single-atom anisotropy. Then conventional magnetization states are reviewed, including macrospins, single domains, multidomains, and domain walls in stripes. Dipolar coupling is examined for lateral interactions in arrays, and for interlayer interactions in films and dots. Finally thermally-assisted magnetization reversal and superparamagnetism are presented. For each topic we sought a balance between well established knowledge and recent developments.Comment: 13 pages. Part of a Special Issue of the C. R. Physique devoted to spinelectronics (2005

Des aspirations identitaires sous l’Etat français : les projets de découpage provincial du Sud-Est (1940-1944)

Vernier Olivier. Des aspirations identitaires sous l’Etat français : les projets de découpage provincial du Sud-Est (1940-1944). In: Le Midi dans la nation française. Actes du 126e Congrès national des sociétés historiques et scientifiques, « Terres et hommes du Sud », Toulouse, 2001. Paris : Editions du CTHS, 2002. pp. 225-236. (Actes du Congrès national des sociétés savantes, 126

Roger Aubenas (1903-1989), un provençal au service de l’histoire du droit méridional

Discipline relativement récente puisque créée en 1896, l’histoire du droit s’est construite avec ses avancées et ses vicissitudes, « naturellement », à la Faculté de droit de Paris avec les premiers maîtres de Paul Viollet (1840-1914) à Pierre Petot (1887-1966) en passant par Emile Chénon (1857-1927) sur lesquels des recherches historiographiques mériteraient d’être menées à l’instar de leurs pairs de la faculté des Lettres. La généalogie de la discipline dans les facultés de province est éga..

Le régionalisme niçois à Paris au XXe siècle.

Vernier Olivier. Le régionalisme niçois à Paris au XXe siècle.. In: Cahiers de la Méditerranée, n°43, 1, 1991. L'identité niçoise [Actes du colloque de Nice, juin 1991] pp. 251-265

Célébrer les mérites civils aux débuts des Trente Glorieuses : les ordres ministériels sous la IVe République (1948-1958)

Poursuivant une volonté de distinguer les citoyens initiée sous la IIIe République, à l’issue de la guerre et pendant les débuts des Trente Glorieuses, la IVe République développe une politique de création d’ordres ministériels – exception quasi unique en Europe –, se surajoutant aux médailles d’honneur. Instruments d’accession à la notoriété, voire de reconnaissance de l’excellence professionnelle, la communication basée sur des sources archivistiques (Archives nationales, chancellerie de la Légion d’honneur, archives départementales), sur des sources imprimées (Bulletin officiel des décorations et médailles) et sur la littérature phaléristique, se veut une évocation de la création et de la montée en puissance de ces ordres décernés aux vivants et une étape dans le processus de notabilisation sociale avec un double primat : soutenir l’œuvre de reconstruction et légitimer le rôle de l’administration par des distinctions qui vont du Mérite artisanal (1948) au Mérite saharien (1958).Vernier Olivier. Célébrer les mérites civils aux débuts des Trente Glorieuses : les ordres ministériels sous la IVe République (1948-1958). In: Les oubliés de l’histoire. Actes du 134e Congrès national des sociétés historiques et scientifiques, « Célèbres ou obscurs : hommes et femmes dans leurs territoires et leur histoire », Bordeaux, 2009. Paris : Editions du CTHS, 2012. pp. 173-182. (Actes des congrès nationaux des sociétés historiques et scientifiques, 134-8