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Magnetic resonance imaging (MRI) based 3D reconstructions were used to derive accurate quantitative data on body volume and functional skin surface areas involved in water transfer in the Palmate Newt (Lissotriton helveticus (Razoumovsky, 1789)). Body surface area can be functionally divided into evaporative surface area that interacts with the atmosphere and controls the transepidermal evaporative water loss (TEWL); ventral surface area in contact with the substratum that controls transepidermal water absorption (TWA); and skin surface area in contact with other skin surfaces when amphibians adopt water-conserving postures. We generated 3D geometries of the newts via volume-rendering by a 'segmentation' process carried out using a graph-cuts algorithm and a Web-based interface. The geometries reproduced the two postures adopted by the newts, i.e., an I-shaped posture characterized by a straight body without tail coiling and an S-shaped posture where the body is huddled up with the tail coiling along it. As a guide to the quality of the surface area estimations, we compared measurements of TEWL rates between living newts and their agar replicas (reproducing their two postures) at 20°C and 60% relative humidity. Whereas the newts did not show any physiological adaptations to restrain evaporation, they expressed an efficient S-shaped posture with a resulting water economy of 22.9%, which is very close to the 23.6% reduction in evaporative surface area measured using 3D analysis. Key words: amphibians, Palmate Newt, Lissotriton helveticus, evaporative water loss, water-conserving behaviour, water relations, modelling, image processing. Des reconstitutions 3D basees sur l'imagerie par resonance magnetique (IRM) ont ete utilisees pour obtenir des donnees quantitatives exactes sur le volume du corps et la superficie de la surface fonctionnelle de la peau qui participent au transfert d'eau chez le triton palme (Lissotriton helveticus (Razoumovsky, 1789)). La superficie du corps peut etre divisee sur la base de la fonction en la superficie intervenant dans l'evaporation, qui interagit avec l'atmosphere et controle la perte d'eau transepidermique par evaporation (TEWL), la superficie ventrale en contact avec le substrat, qui controle l'absorption d'eau transepidermique (TWA), et la superficie de la peau en contact avec d'autres surfaces cutanees quand l'animal adopte une posture de conservation d'eau. Nous avons produit des geometries 3D des tritons par un processus de segmentation realise avec un algorithme de coupe de graphe et une interface Web. Les geometries reproduisaient les deux postures adoptees par les tritons, soit une posture en I caracterisee par un corps droit sans enroulement de la queue et une posture en S dans laquelle la queue est enroulee le long du corps recroqueville. Pour evaluer la qualite des estimations des superficies, nous avons compare des mesures des taux de TEWL de tritons vivants et de leurs repliques en gelose (des reconstitutions des deux postures) a 20°C et 60 % d'humidite relative. Si les tritons ne presentaient aucune adaptation physiologique visant a limiter l'evaporation, ils adoptaient toutefois une posture en S efficace dont resultait une economie d'eau de 22,9 %, tres semblable a la reduction de 23,6 % de la superficie des surfaces d'evaporation mesuree par l'analyse 3D. [Traduit par la Redaction] Mots-cles : amphibiens, triton palme, Lissotriton helveticus, perte d'eau par evaporation, comportement de conservation d'eau, relations hydriques, modelisation, traitement d'images., Introduction Understanding and predicting how environmental changes might affect amphibian relationships with their physical environment is a serious challenge to conservation biology. These wet-skinned ectotherms have a highly permeable, heavily [...]

Through the history of the Commission du Génie Biomoléculaire, we analyse the transformations of the expertise and regulation of GM crops in France since 1986. These transformations illustrate wider changes in the relations between scientific advice, policy, research communities and public arenas (media, courts…).

Using three clinical examples, this paper explores the determinants of what the author refers to as the "cuckoo phenomenon" that is, the propensity of some participants in psychotherapy groups to take up more space, and in particular to monopolize speaking time, to the detriment of other members of the group. Beyond the problem of the "cuckoo" participant and the rivalry implicated, the cuckoo phenomenon proves to be a group formation resulting from the regressive transferential expectations encouraged by the group. It seems determined by various transferential expectations, including the expectation of a powerful maternal object capable of responding to a great need for support, the tendency to offset the lack of such an object, or the expectation of a protective father in the face of this archaic maternal object desired and feared at the same time. [ABSTRACT FROM AUTHOR]

This text presents an epistolary exchange between two psychotherapists working in a psychoanalytic group. Their dialogue provides an insight into the transference-counter-transference processes at play, and highlights the way they think about the group through the associative work that takes place between sessions. This is a foresight approach, since this exchange begins at a crucial moment in the group process, without any knowledge of future events, and continues over the course of several months. The words of one of the participants ("Can I start a subject?") constitute the starting point and the common thread used to reflect on the work of subjectivation allowed by the group setting. By exploring some significant moments in the life of the group, including the formation of a couple, this text highlights the complexity of group phenomena within psychoanalytic group psychotherapy. [ABSTRACT FROM AUTHOR]

This text puts forward the idea that today's neoliberal culture can lead to the exile of the tragic dimension of the human condition, including the conflictual aspects of relationships, the inevitability of grief, and aging. It draws a parallel between the society described in Aldous Huxley's novel Brave New World (1932) and several characteristics of our world today, including the frequent use of antidepressants, the importance given to entertainment, the rhetoric of success, performance, and novelty. A critical look is cast on a possible unscientific use of research results on the effectiveness of psychotherapy, highlighting how the complexity of this research and its results can be obscured in favour of "conclusive data" and "best practices" that best fit the accounting and economic logics privileged by health administrators. [ABSTRACT FROM AUTHOR]

A partir de conceptions différenciées du public et de la science, ce papier présente quatre modèles génériques pour la gouvernance des risques. Ces modèles idéal-typiques permettent de mieux poser deux questions essentielle : la question de la participation du public et celle du traitement de l’incertitude. Concernant le dossier des OGM, nous utilisons ces modèles pour montrer que l’expérience Européenne actuelle ne peut pas être assimilée à l’expérience américaine de procéduralisation et d’ouverture de l’expertise dans les années 1970. C’est précisément le caractère profondément original de cette expérience qu’il faut saisir afin de mieux en dessiner les enjeux.