Émission, médiation, réception : les opérations constitutives d'une réforme par imprégnation

Cet article est téléchargeable sur : http://www.persee.fr/web/revues/home/prescript/article/rfsp_0035-2950_2000_num_50_2_395470International audienceThis article discusses the conditions for reform success and the implementation of new ideas and visions. It is based on an empirical study of the restructuring of one instance of regional cooperation - Nordic cooperation since 1980. It first suggests a repertoire of actors (producer, mediator, receiver) whose combination in a reforming system is necessary to the success of any reform. It then develops a model that describes reform as a phenomenon of impregnation, whose success depends on the existence and the strength of the reforming system(s), the powers of the reformed system and the impact of time.Portant sur les conditions qui président au succès d'une réforme et à la mise en oeuvre de nouvelles idées et visions, cet article repose sur l'étude empirique de la réarticulation subie à partir de 1980 par une coopération régionale : la coopération nordique. Il propose tout abord un répertoire d'acteurs (émetteur médiateur récepteur) dont la combinaison en un système réformateur serait nécessaire au succès de toute réforme. Il développe ensuite un modèle de la réforme qui la décrit comme un phénomène d'imprégnation dont la réussite dépendrait de l'existence et de la force du ou des système(s) réformateur(s), des compétences du système réformé et des effets du temps

Evaluation of diffusive gradients in thin films technique (DGT) for measuring Al, Cd, Co, Cu, Mn, Ni, and Zn in Amazonian rivers

Studies concerning the lability and bioavailability of trace metals have played a prominent role in the search for contamination of water resources. This work describes the first application yet of the diffusive gradients in thin films technique (DGT) to the determination of the fraction of free plus labile metals in waters from the Amazon Basin. Due to the complexity of the use of DGT for samples with low ionic strength and high organic matter content (characteristic of Amazonian rivers), a new analytical procedure was developed. The method is based on the determinations of apparent diffusion coefficients (Dap) in the laboratory, by performing deployments in samples collected in the corresponding sites of study. The Dap thereby determined is then used for in situ measurements. The suitability of the proposed approach for determination of labile Al, Cd, Co, Cu, Mn, Ni, and Zn in the Amazon River and Rio Negro (English: Black River) was evaluated. Except for Co, Mn (in a deployment at Rio Negro), Ni and Zn (in a deployment at Amazon River), labile in situ measurements were lower or similar to dissolved concentrations, indicating suitability of the proposed approach. © 2013 Springer Science+Business Media Dordrecht