62 research outputs found
Du fil des Parques au fil des fĂ©es : la fabrique du conte dans « Serpentin vert » de Madame dâAulnoy
Dans le conte « Serpentin vert » de Marie-Catherine dâAulnoy, lâĂ©preuve du filage imposĂ©e Ă lâhĂ©roĂŻne par la fĂ©e Magotine, qui assume le rĂŽle de VĂ©nus dans le conte dâAmour et PsychĂ©, loin dâĂȘtre imputable Ă la seule fantaisie de la conteuse, tĂ©moigne du jeu intertextuel trĂšs subtil qui caractĂ©rise ce conte et en fait un manifeste esthĂ©tique. Ce motif se justifie dâabord en tant que rĂ©miniscence du texte dâApulĂ©e et de sa rĂ©Ă©criture par La Fontaine, Les Amours de PsychĂ© et Cupidon. En suggĂ©rant que son hĂ©roĂŻne doit filer son propre destin et celui de son amant, Marie-Catherine dâAulnoy condense en une image son interprĂ©tation de PsychĂ© comme « belle farouche », tout en exploitant les riches potentialitĂ©s symboliques du fil. La figure dâArachnĂ© sâassocie Ă celle de la Parque pour symboliser le passage du fil du destin Ă celui de lâĂ©criture.In Marie-Catherine dâAulnoyâs â The Green Serpent â, the fairy Magotine, taking up the role of Venus in Apuleiusâs tale of Eros and Psyche, sets up very difficult trials for the heroine Laidronnette. The task of spinning, in particular, reveals the subtle intertextual play that makes this tale a programmatic tale. The motif alludes to Apuleiusâs Golden Ass as well as to La Fontaineâs own rewriting of the classic tale in Les Amours de PsychĂ© et Cupidon. Laidronnette, as far as she must spin not only her own fate but also the fate of her lover, embodies dâAulnoyâs reinterpretation of Psyche as an â inexorable beauty â who refuses to give in to love. The author also mobilizes the mythological and symbolic resonances of thread, insofar as Laidronnette combines the features of both a Fate and the weaver Arachne : in this sense, the thread of life becomes indistinguishable from the thread of writing
Traitement de donnĂ©es lidar Ă retour d'onde complĂšte pour l'extraction de paramĂštres forestiers et de modĂšle numĂ©rique de terrain : validataion en forĂȘt de conifĂšres dans les Alpes
International audienceSmall footprint discrete return lidar data have already proved useful for providing information on forest areas. During the last decade, a new generation of airborne laser scanners, called full-waveform (FW) lidar systems, has emerged. They digitize and record the entire backscattered signal of each emitted pulse. Fullwaveform data hold large potentialities. In this study, we investigated the processing of raw full-waveform lidar data for deriving Digital Terrain Model (DTM) and Canopy Height Model (CHM). The main objective of this work was to compare geometric information derived from full-waveform and multi-echo data for various stands. An enhanced peak detection algorithm developed in a previous study was used to extract target positions from full-waveform data on plots under different stand characteristics. The resulting 3D point clouds were compared to the discrete return lidar observations provided by the lidar operator. Ground points were then identified using an original classification algorithm. They were used to derive DTMs which were compared to ground truth. Digital Surface Models were obtained from first echoes and canopy height models were then computed. Detecting weak echoes, when processing full-waveform data, enabled to better describe the canopy shape and to penetrate deeper into forest cover. However DTM was not significantly improved
Traitement de données à retour d'onde complÚte : modélisation du signal brut
International audienceUnlike airborne multi-echo laser scanner systems, full-waveform systems are able to digitize and record the entire backscattered signal of each laser pulse. It has been demonstrated that decomposing the return waveforms into a mixture of Gaussian components was suitable. In this paper, we focus on the improvement of peak detection and of raw signal modelling. Refined peak detection greatly increased the number of detected targets as well as their positional accuracy. Models more complex than the Gaussian model, such as the Lognormal or generalized Gaussian functions, were introduced and their contribution to waveform processing was studied. In this way, fitting of asymmetric, peaked or flattened echoes located both in urban and forested areas could be improved. Moreover, introduction of new echo parameters allowed the extraction of additional information on the target shape. This should make easier the decorrelation of geometric and radiometric influences on the signal and, as a consequence, the improvement of point cloud classification algorithms
Processing full-waveform lidar data in an alpine coniferous forest: assessing terrain and tree height quality
International audienceSmall footprint full-waveform airborne lidar systems hold large opportunities for improved forest characterisation. To take advantage of full-waveform information, this paper presents a new processing method based on the decomposition of waveforms into a sum of parametric functions. The method consists of an enhanced peak detection algorithm combined with an advanced echo modelling including Gaussian and generalized Gaussian models. The study focussed on the qualication of the extracted geometric information. Resulting 3D point clouds were compared to the point cloud provided by the operator. 40 to 60 % additional points were detected mainly in the lower part of the canopy and in the low vegetation. Their contribution to Digital Terrain Models (DTMs), Canopy Height Models (CHMs) was then analysed. The quality of DTMs and CHM-based heights was assessed using eld measurements on black pine plots under various topographic and stand characteristics. Results showed only slight improvements, up to 5 cm bias and standard deviation reduction. However both tree crowns and undergrowth were more densely sampled thanks to the detection of weak and overlapping echoes, opening up opportunities to study the detailed structure of forest stands
High prevalence of PRPH2 in autosomal dominant retinitis pigmentosa in France and characterization of biochemical and clinical features.
International audiencePURPOSE:To assess the prevalence of PRPH2 in autosomal dominant retinitis pigmentosa (adRP), to report six novel mutations, to characterize the biochemical features of a recurrent novel mutation and to study the clinical features of adRP patients.DESIGN:Retrospective clinical and molecular genetic study.METHODS:Clinical investigations included visual field testing, fundus examination, high-resolution spectral-domain optical coherence tomography (OCT), fundus autofluorescence imaging and electroretinogram (ERG) recording. PRPH2 was screened by Sanger sequencing in a cohort of 310 French families with adRP. Peripherin-2 protein was produced in yeast and analyzed by Western blot.RESULTS:We identified 15 mutations, including 6 novel and 9 previously reported changes in 32 families, accounting for a prevalence of 10.3% in this adRP population. We showed that a new recurrent p.Leu254Gln mutation leads to protein aggregation, suggesting abnormal folding. The clinical severity of the disease in examined patients was moderate with 78% of the eyes having 1 to 0.5 of visual acuity and 52% of the eyes retaining more than 50% of the visual field. Some patients characteristically showed vitelliform deposits or macular involvement. In some families, pericentral RP or macular dystrophy were found in family members while widespread RP was present in other members of the same families.CONCLUSIONS:The mutations in PRPH2 account for 10.3% of adRP in the French population, which is higher than previously reported (0-8%) This makes PRPH2 the second most frequent adRP gene after RHO in our series. PRPH2 mutations cause highly variable phenotypes and moderate forms of adRP, including mild cases which could be underdiagnosed
Regulation of the Na,K-ATPase Gamma-Subunit FXYD2 by Runx1 and Ret Signaling in Normal and Injured Non-Peptidergic Nociceptive Sensory Neurons
Dorsal root ganglia (DRGs) contain the cell bodies of sensory neurons which relay nociceptive, thermoceptive, mechanoceptive and proprioceptive information from peripheral tissues toward the central nervous system. These neurons establish constant communication with their targets which insures correct maturation and functioning of the somato-sensory nervous system. Interfering with this two-way communication leads to cellular, electrophysiological and molecular modifications that can eventually cause neuropathic conditions. In this study we reveal that FXYD2, which encodes the gamma-subunit of the Na,K-ATPase reported so far to be mainly expressed in the kidney, is induced in the mouse DRGs at postnatal stages where it is restricted specifically to the TrkB-expressing mechanoceptive and Ret-positive/IB4-binding non-peptidergic nociceptive neurons. In non-peptidergic nociceptors, we show that the transcription factor Runx1 controls FXYD2 expression during the maturation of the somato-sensory system, partly through regulation of the tyrosine kinase receptor Ret. Moreover, Ret signaling maintains FXYD2 expression in adults as demonstrated by the axotomy-induced down-regulation of the gene that can be reverted by in vivo delivery of GDNF family ligands. Altogether, these results establish FXYD2 as a specific marker of defined sensory neuron subtypes and a new target of the Ret signaling pathway during normal maturation of the non-peptidergic nociceptive neurons and after sciatic nerve injury
"LucrĂšce et Tchouang-tseu : Albert Camus lecteur du De rerum natura"
International audienceCet article a pour point de dĂ©part une note des Carnets dans laquelle Camus affirme que « Tchouang-Tseu [âŠ] a le point de vue de LucrĂšce ». Cette note offre une clĂ© de lecture pour reconsidĂ©rer la lecture que LucrĂšce a faite du poĂšte latin et en particulier le rĂŽle dĂ©cisif qu'a jouĂ© le De rerum natura dans l'Ă©criture de La Peste. Elle Ă©claire aussi la place qui lui est rĂ©servĂ©e dans L'Homme rĂ©voltĂ©
Lectures de LucrÚce: textes réunis et présentés par Sylvie Ballestra-Puech
International audience« Parmi ceux qui naĂźtront aprĂšs nous, nombre croiront s'entretenir avec LucrĂšce lui-mĂȘme sur la nature des choses » Ă©crit le clairvoyant Vitruve. Ce livre rĂ©unit quelques fragments significatifs de la conversation sĂ©culaire que savants et crĂ©ateurs entretiennent avec LucrĂšce. Une approche rĂ©solument transdisciplinaire a Ă©tĂ© choisie pour aborder ces Ă©chos lucrĂ©tiens qui rĂ©sonnent dans tous les domaines de la connaissance humaine dĂšs lors que le poĂšte latin affronta la complexitĂ© du rĂ©el avec pour seules armes les puissances conjuguĂ©es de lâimagination et de lâart. Les liens indissolubles que le De rerum natura tisse entre science, Ă©thique et esthĂ©tique expliquent la pluralitĂ© des lectures qui ont pu en ĂȘtre faites, chacune rĂ©vĂ©lant les spĂ©cificitĂ©s dâune Ă©poque autant quâune appropriation singuliĂšre. LucrĂšce nous a lĂ©guĂ© un trĂ©sor dâimages et dâoutils conceptuels dont la fĂ©conditĂ© heuristique paraĂźt inĂ©puisable, comme en tĂ©moigne lâĂ©tonnante fortune thĂ©orique du clinamen
"LucrĂšce et Tchouang-tseu : Albert Camus lecteur du De rerum natura"
International audienceCet article a pour point de dĂ©part une note des Carnets dans laquelle Camus affirme que « Tchouang-Tseu [âŠ] a le point de vue de LucrĂšce ». Cette note offre une clĂ© de lecture pour reconsidĂ©rer la lecture que LucrĂšce a faite du poĂšte latin et en particulier le rĂŽle dĂ©cisif qu'a jouĂ© le De rerum natura dans l'Ă©criture de La Peste. Elle Ă©claire aussi la place qui lui est rĂ©servĂ©e dans L'Homme rĂ©voltĂ©
Variations sur les Tristes et les Pontiques dans Die letzte Welt (1988) de Christoph Ransmayr
International audienceChristoph Ransmayr a lui-mĂȘme invitĂ© ses lecteurs Ă prĂȘter toute leur attention Ă la rĂ©Ă©criture des MĂ©tamorphoses dâOvide dans son roman Die letzte Welt et la critique a largement rĂ©pondu Ă son invitation. Quoique moins fortement revendiquĂ©e et beaucoup moins Ă©tudiĂ©e, la prĂ©sence intertextuelle des lettres dâexil nâen est pas moins dĂ©terminante et cet article sâefforce de montrer quâelle permet dâexpliquer certaines particularitĂ©s de lâespace autant que de lâintrigue de ce roman, pour peu quâon lâenvisage comme une fiction critique mettant en lumiĂšre lâĂ©troite imbrication de lâĂ©criture de lâexil et de celle du mythe
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