Nouvelle approche dans l'etude de la dynamique sedimentaire des estuaires macrotidaux a faible debit fluvial

The short estuaries located on the English Channel and Atlantic coasts are distinguished by short-lived flood peaks and a very small average water discharge. Affected by large tide ranges during spring tides, they exhibit very different hydrosedimentological characteristics with low fluvial sediment input compared to marine sediment input. The formulation of a mathematical model for cohesive suspended matter transport and bottom evolution has necessitated a comparative study of bathymetric data and the recording of seasonal sediment movement in the Morlaix estuary

L'industrie agro-alimentaire bretonne dans la perspective du grand marche europeen

*Observatoire Economique des Industries Agricoles et Alimentaires 111 Bd de Lattre de Tassigny 35000 RENNES (FRA) Diffusion du document : Observatoire Economique des Industries Agricoles et Alimentaires 111 Bd de Lattre de Tassigny 35000 RENNES (FRA)Comment cet evenement majeur est-il percu par les industriels bretons du secteur agro-alimentaire ? L'enquete effectuee aupres de 69 entreprises permet de repondre a cette question. En particulier il est possible de comparer entre elles des reponses representatives du tissu industriel regional et celles que fournit l'enquete nationale effectuee avec le meme questionnaire. L'analyse des reponses donnees par les industriels bretons permet de preciser les points qui provoquent le plus de reponses defavorables ou d'interrogations. On remarque que les consequences du marche unique sur les PME suscitent beaucoup d'inquietudes puisque de toutes les questions posees, c'est la seule qui recueille une majorite de reponses favorables. A un degre moindre, s'exprime egalement, une certaine crainte concernant la creation d'entreprises et l'avenir des firmes francaises. Les industriels bretons pensent, egalement, que l'eloignement des grands centres de consommation est un des points faibles de la region dans la competition europeenne. Par ailleurs, ils redoutent qu'une concurrence accrue entraine une degradation de la qualite des produits

Regulation of murine airway responsiveness by endothelial nitric oxide synthase

Nitric oxide (NO) is a potent vasodilator, but it can also modulate contractile responses of the airway smooth muscle. Whether or not endothelial (e) NO synthase (NOS) contributes to the regulation of bronchial tone is unknown at present. Experiments were designed to investigate the isoforms of NOS that are expressed in murine airways and to determine whether or not the endogenous release of NO modulates bronchial tone in wild-type mice and in mice with targeted deletion of eNOS [eNOS(-/-)]. The presence of neuronal NOS (nNOS), inducible NOS (iNOS), and eNOS in murine trachea and lung parenchyma was assessed by RT-PCR, immunoblotting, and immunohistochemistry. Airway resistance was measured in conscious unrestrained mice by means of a whole body plethysmography chamber. The three isoforms of NOS were constitutively present in lungs of wild-type mice, whereas only iNOS and nNOS were present in eNOS(-/-) mice. Labeling of nNOS was localized in submucosal airway nerves but was not consistently detected, and iNOS immunoreactivity was observed in tracheal and bronchiolar epithelial cells, whereas eNOS was expressed in endothelial cells. In wild-type mice, treatment with N-nitro-L-arginine methyl ester, but not with aminoguanidine, potentiated the increase in airway resistance produced by inhalation of methacholine. eNOS(-/-) mice were hyperresponsive to inhaled methacholine and markedly less sensitive to N-nitro-L-arginine methyl ester. These results demonstrate that the three NOS isoforms are expressed constitutively in murine lung and that NO derived from eNOS plays a physiological role in controlling bronchial airway reactivity.link_to_subscribed_fulltex

Golfe normano-breton: etude regionale integree 1. Presentation de l'etude, hydrodynamique et sedimentologie. 2. Milieu pelagque. 3. Benthos subtidal. 4. Estrans et zones humides. 5. Aspects socio-economiques. 6. Baie du Mont Saint-Michel

SIGLECNRS RP 350 (40) (1-6) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc