Pédologie II : Notions de base (Fertilité des sols - Éléments nutritifs - Biologie et biodiversité des sols - Menaces qui pèsent sur les sols)

Conference given outside the academic context (2010)

Pédomorphose facultative chez Triturus alpestris : comparaison des structures d'âge des tritons métamorphes et pédomorphes

Conference (1998)

La pédomorphose est définie comme la rétention de caractères subadultes ancestraux chez le descendant adulte. Ce processus hétérochronique est relativement répandu au sein des urodèles. Ainsi, les adultes ... [more ▼]

La pédomorphose est définie comme la rétention de caractères subadultes ancestraux chez le descendant adulte. Ce processus hétérochronique est relativement répandu au sein des urodèles. Ainsi, les adultes reproducteurs, dénommés "pédomorphes", conservent les fentes branchiales larvaires. Chez le Triton alpestre, sujet de notre étude, la pédomorphose est facultative en ce sens que les deux traits d'histoire de vie - la métamorphose et la pédomorphose - existent. Certaines populations ne présentent que des individus métamorphes, tandis que d'autres présentent un mélange des deux formes. La pédomorphose était souvent associée à des milieux stables et froids d'altitude. Mais différentes populations ont aussi été découvertes dans des milieux instables de basse altitude. La présence d'animaux pédomorphes dans ce type de milieu ne paraissait dès lors pas adaptative. L'objectif de cette étude a été d'étudier les structures d'âge de deux populations où cohabitent tritons pédomorphes et métamorphes : une population peuplant un lac profond (le lac de la Cabane) situé à 1950 mètres d'altitude dans les Alpes-de-Haute-Provence (France) et une autre habitant une petite mare située à une altitude de 600 mètres à Parana, en Toscane (Italie). L'âge des animaux a été déterminé par squelettochronologie sur phalange et humérus. Au total, nous avons pu déterminer l'âge de 116 adultes de la population française et 128 de la population italienne. Nos résultats montrent une différence de trait d'histoire de vie nette entre les populations de haute et de basse altitude. Ainsi, au lac de la Cabane les structures d'âge des animaux métamorphes et pédomorphes sont identiques, tant en ce qui concerne les mâles que les femelles. La taille des animaux est elle aussi identique. Par contre, à Parana, les pédomorphes atteignent leur maturité sexuelle très jeunes : à un an chez les mâles et à un ou deux ans chez les femelles. Les métamorphes ne deviennent, par contre, matures que plus tardivement : les mâles, à 2-3 ans, et les femelles à 4-5 ans. La pédomorphose ne dure que peu de temps car les pédomorphes peuvent se métamorphoser. Les pédomorphes de cette population sont plus petits que les métamorphes. Chez le Triton alpestre, des cas de populations pédomorphiques ne sont constatés que dans les péninsules italiennes et balkaniques, laissant ainsi supposer une base génétique. Ayant montré que le succès des pédomorphes et leur trait d'histoire de vie, en l'occurrence leur structure d'âge, diffèrent entre les populations, nous pouvons considérer la pédomorphose comme une stratégie alternative influencée par différents facteurs environnementaux. Seules les populations ayant un potentiel génétique pour la pédomorphose peuvent répondre aux pressions de l'environnement, lesquelles, selon leurs caractéristiques, peuvent mener à des patrons de pédomorphose de différents types. En cas de catastrophe ou de colonisation de nouveaux milieux, la pédomorphose par progenèse permet une augmentation rapide de la population. Par contre dans des systèmes d'altitude, où une maturité précoce est peut-être impossible, l'avantage d'une stratégie pédomorphe peut être recherché, par exemple, au niveau des niches alimentaires ou spatiales, ce qui constitue un autre volet de notre étude. [less ▲]

Pédophilie : un synopsis clinique

in Sexologies (2000), 9(33), 8-17

Conceiving pedophilic sexuality as a sexuality resulting from a fack of grtifying relationships to adults is an important operational reference for the clinician. In this way, the obstacles to sexual ... [more ▼]

Conceiving pedophilic sexuality as a sexuality resulting from a fack of grtifying relationships to adults is an important operational reference for the clinician. In this way, the obstacles to sexual satisfaction with adults can become the privileged target of therapeutic and preventive acts.The narcissic fragility is certainly an obstacle common to almost all the pedophilic patterns. Beyond this common denominator, the individual cases are characterized by strong dissimilarities. The variety of the cases justifies the attempts to classify the different types of pedophiles. But the typological systems are also quite different, depending on the theorical and methodological preferences of their authors. Starting from the ideas of several authors, this article try to sum up the variety of pedophilic functioning in four axes of variation. At last, the article stresses the imortance of contexts of life as factors leading a predisposed personality to transgression [less ▲]

Peer Blues Festival (B)

in LIVING BLUES (1989), (88), 8

Photos : B.B. KING , FRED CLARK , JOHNNY OTIS, OTIS CLAY , EDDIE KIRKLAND

Peer Festival 1985

in LIVING BLUES A Journal of the Black American Blues Tradition (1985), (66), 5-6

Compte rendu du festival avec photos ( Johnny COPELAND)

Peers, leisure, delinquant acting-out, collective delinquency

in Younger-Tas, J. (Ed.) Delinquant behavior among people in the Western countries : tome II (1999)

PEGASE - A space interferometer for the spectro-photometry of Pegasides

Scientific conference (2004, August 25)

Pegase is an answer to the CNES call for ideas for a scientific payload on its Formation Flying technological mission. It proposes a Bracewell interferometer operating in the infrared (1.5 – 6 microns ... [more ▼]

Pegase is an answer to the CNES call for ideas for a scientific payload on its Formation Flying technological mission. It proposes a Bracewell interferometer operating in the infrared (1.5 – 6 microns) and visible regimes. It has small telescopes (40 cm) but a substantial baseline (25 to 500 m). Its angular resolution reaches 1 mas at 4 microns and 100 micro-as at 0.4 microns. Its main scientific objectives are the spectroscopic study of weak companions including pegasides and brown dwarfs bounded to other stars. The goal is to determine the composition of the atmospheres of these objects as well as their cloud structure. [less ▲]

PEGASE : UN MODÈLE INTÉGRÉ BASSIN HYDROGRAPHIQUE / RIVIÈRES POUR LA DIRECTIVE CADRE EUROPÉENNE

Conference (2009, April 09)

Presentation of the PEGASE model (Planification Et Gestion de l’ASsainissement des Eaux), developed by the Aquapole Aquapole. New operational way to assess the evolution of the river quality in terms of ... [more ▼]

Presentation of the PEGASE model (Planification Et Gestion de l’ASsainissement des Eaux), developed by the Aquapole Aquapole. New operational way to assess the evolution of the river quality in terms of presures on them, as well as a tool to help competent authorities to optimise the cost/efficiency ratio of the measures foreseen to reduce the impact of these pressures. [less ▲]

The PEGASE project: characterisation of "Pegasi planets" and Brown Dwarfs

in Combes, F.; Barret, D.; Contini, T. (Eds.) et al SF2A-2004: Semaine de l'Astrophysique Francaise (2004, December 01)

I will present the PEGASE project proposed within the framework of the CNES call for idea on flights in formation. This ambitious project, gathering a dozen laboratories, proposes an interferometry ... [more ▼]

I will present the PEGASE project proposed within the framework of the CNES call for idea on flights in formation. This ambitious project, gathering a dozen laboratories, proposes an interferometry mission in infrared I(1.5 to 6 µm) with spectroscopic capabilities. The bases of the interferometer will reach up to 500m, giving to PEGASE a resolution higher than the milli-arcsecond. The interferometric recombination includes a very simple mode, measurement of the visibility by excursion of the optical path difference and a mode in black fringe or nulling. The very high angular resolution of the instrument and high dynamical range with the nulling mode will allow to consider exciting scientific objectives: the characterization of Pegasids or hot Jupiters, the study of the internal structure and the atmospheres of brown dwarfs and the analysis of the internal areas of proto-planetary disks. I will first of all describe the basic configuration of the mission and will show that its simplicity ensures the feasibility of the project. I will explain then the relevance of such an instrument for the characterization of Pegasids. I will detail finally the various possible technical options to be attached to the initial version, in order to increase the effectiveness of the mission and to extend its scientific objectives. [less ▲]

Pegase, A software dedicated to Surface Water Quality Assessment and to European database reporting

in Hrebiceck, Jiri (Ed.) Proceedings of the European conference TOWARDS eENVIRONMENT, Opportunities of SEIS and SIZE: Integrating Environmental Knowledge in Europe (2009, March)

The Aquapôle of the University of Liège has been involved in environment modelling for more than 20 years. Its R&D unit focused on the domain of surface water, targeted to water quality. One of its ... [more ▼]

The Aquapôle of the University of Liège has been involved in environment modelling for more than 20 years. Its R&D unit focused on the domain of surface water, targeted to water quality. One of its environmental models, called PEGASE (Planification Et Gestion de l’ASsainissement des Eaux), French acronym for ―Planning and management of water purification‖ is devoted to the characterization of the environmental state of surface water, at the scale of a whole watershed, basin and district. The software has been used operationally in several countries like France and Benelux, but several calculations have also been performed at international level for the international commissions in charge of the Scheldt and the Meuse. PEGASE model requires as input, at least data like digital terrain models, water flow, water level and other hydrodynamic measurements in some geo-localized points, diffuse loads properties, ecological model data (to characterize bacteria, phytoplankton, zooplankton, macrophytes, shells, etc…), chemical discharges (from industry and cities) and treatment plant effect. The output of the software consists in tables, graphs and maps, showing the state of various calculated parameters of quality (DO, BOD, COD, N, P, Chla,… + indices) either at a specified time, along the river, or the temporal evolution at a given point. It provides printed maps or animations of the evolution of the results on the basin. The software is able to simulate non stationary scenarios from a local scale, up to a global scale i.e. a few km² to hundreds of thousands km² and handles the entire river tree (hundreds to thousands of water bodies). Some results of the model are already used to populate the SoE-Wise databases. On another hand, the model is a tool to validate and check consistency of SoE-Wise data at district (and thus international) level. The flexibility of the model enables to choose the time (daily to yearly periods) and spatial (watershed, water body, district, region, country …) scales of the expected results. PEGASE is also a full-scale operational tool for WFD implementation and WISE databases. This means that our partners handle a software (also known as the model) directly usable – and of direct help – in the implementation of the WFD and other water related directives. The model allows the member states to compare efficiently the collected international WISE data and populate database with relevant model results. We propose not only to read the data directly from the database to avoid manipulation mistakes, but also we propose to generate output data in a format directly exploitable by WISE databases administration. [less ▲]