Search

Your search keyword '"Escande, D."' showing total 502 results
Start Over Author "Escande, D."
502 results on '"Escande, D."'

201. Positive inotropic effects of RP 62719, a new pure class III antiarrhythmic agent, on guinea pig myocardium.

Author

Beregi, J P, Escande, D, Coudray, N, Mery, P, Mestre, M, Chemla, D, and Lecarpentier, Y

Abstract

The mechanical effects of RP 62719 [(-)1-[-2-(3,4-dihydro-2H-1- benzopyran-4-yl)ethyl]-4-(3,4-dimethoxyphenyl)-piperidine] were tested in vitro on guinea pig left ventricular papillary muscle. RP 62719 is a novel pure class III antiarrhythmic agent known to prolong the cardiac action potential duration by selectively blocking the inward rectifying K+ current. Mechanical parameters were determined from contraction and relaxation phases under isotonic and isometric conditions. At a concentration of 0.02 microM, RP 62719 did not produce significant effects on inotropy or lusitropy. At 0.2 and 2 microM, the drug improved contraction under both heavy and low loading conditions, as evidenced by a 30% increase in maximum unloaded shortening velocity (Vmax, P < .001), peak amplitude of shortening (delta L, P < .001), peak isometric active force normalized per cross-sectional area (AF/s, P < .001) and positive peak of the force derivative per mm2 (+dF/s, P < .001). At the same concentrations, positive lusitropic effects were evidenced by an increase in maximum lengthening velocity (maxVr) and negative peak of force derivative per mm2 (-dF/s, P < .001). At a higher concentration (20 microM), effects of RP 62719 on inotropy and lusitropy were less marked, thus accounting for the bell-shaped form of the dose-response curve. An increase in the extracellular Ca++ concentration from 2.5 to 3.75 mM improved inotropy to a similar extent (+30-50%) as did 2 microM RP 62719. However, lusitropy and mechanical coupling between contraction and relaxation were not modified in the same proportion under RP 62719 and under 3.75 mM Ca++.(ABSTRACT TRUNCATED AT 250 WORDS)

Published
1992

202. Potassium channel openers act through an activation of ATP-sensitive K+ channels in guinea-pig cardiac myocytes

Author

Escande, D., Thuringer, D., Guern, S., Courteix, J., Laville, M., and Cavero, I.

Abstract

In a previous article (Escande et al. 1988a), we have shown that cromakalim (BRL 34915), a potassium channel opener (PCO), is a potent activator of ATP-sensitive K+ channels in cardiac cells. In the present article, the influence on K+ channels of two other potassium channel openers chemically unrelated to cromakalim, RP 49356 and pinacidil, has been investigated in patch-clamped isolated cardiac myocytes. In the whole-cell configuration, K+ currents were recorded in the presence of 50 µM TTX and 3 µM nitrendipine or 3 mM cobalt. Like cromakalim, RP 49356 or pinacidil activated a time-independent outward current at 33–35°C but not at 19–21°C, which showed little voltage-dependency in the potential range -60 to +60 mV. Its amplitude was a function of the agonist concentration, e.g. it was 2.1±0.4 nA at +60 mV with 30 µM RP 49356 and 4.3±0.8 nA with 300 µM. In control conditions, glibenclamide, a blocker of K+-ATP channels in pancreatic and heart cells, affected neither the inward rectifier,iK1, nor the delayed K+ current,iK. At 3 µM, glibenclamide fully prevented the effects of 300 µM RP 49356 or pinacidil. At lower concentrations, glibenclamide partially counteracted the activation by PCOs of a K+ current. In the cell-attached contiguration, externally applied RP 49356 or pinacidil caused opening of large channels which reversed around 0 mV in a high K+ external medium. In inside-out patches, both RP 49356 or pinacidil activated K+-ATP channels by increasing the time period for which the channels remained in the open state. It is concluded that, like cromakalim, RP 49356 and pinacidil are potent activators of K+-ATP channels in cardiac myocytes.

Published
1989
Full Text
View/download PDF

203. The pharmacology of ATP-sensitive K+ channels in the heart

Author

Escande, D.

Abstract

Conclusion What is known to date about the pharmacology of ATP-sensitive K+ channels has provided evidence that important differences exist between cardiac and pancreatic cells: (i) sulphonylureas are about two orders of magnitude more potent in the pancreas than in the heart; (ii) diazoxide exerts opposite effects in the heart and in the pancreas.

Published
1989
Full Text
View/download PDF

204. Polyethylenimine but not cationic lipids promotes transgene delivery to the nucleus in mammalian cells.

Author

Pollard, H, Remy, J S, Loussouarn, G, Demolombe, S, Behr, J P, and Escande, D

Abstract

The beta-galactosidase reporter gene, either free or complexed with various cationic vectors, was microinjected into mammalian cells. Cationic lipids but not polyethylenimine or polylysine prevent transgene expression when complexes are injected in the nucleus. Polyethylenimine and to a lesser extent polylysine, but not cationic lipids, enhance transgene expression when complexes are injected into the cytoplasm. This latter effect was independent of the polymer vector/cDNA ionic charge ratio, suggesting that nucleic acid compaction rather than surface charge was critical for efficient nuclear trafficking. Cell division was not required for nuclear entry. Finally, comparative transfection and microinjection experiments with various cell lines confirm that barriers to gene transfer vary with cell type. We conclude that polymers but not cationic lipids promote gene delivery from the cytoplasm to the nucleus and that transgene expression in the nucleus is prevented by complexation with cationic lipids but not with cationic polymers.

Published
1998

205. A dominant negative isoform of the long QT syndrome 1 gene product.

Author

Demolombe, S, Baró, I, Péréon, Y, Bliek, J, Mohammad-Panah, R, Pollard, H, Morid, S, Mannens, M, Wilde, A, Barhanin, J, Charpentier, F, and Escande, D

Abstract

Mutations in the KvLQT1 gene are the cause of the long QT syndrome 1. KvLQT1 gene product is associated with the regulator protein IsK to produce a component of the delayed rectifier K+ current in cardiac myocytes. We identified an N-terminal truncated isoform of the KvLQT1 gene product, referred to as isoform 2. In RNase protection assays, isoform 2 represented 28.1 +/- 0.6% of the total KvLQT1 expression in the human adult ventricle. COS-7 cells injected intranuclearly with KvLQT1 isoform 1 cDNA exhibited a fast-activating K+ current, whereas those injected with a KvLQT1 isoform 1 plus IsK cDNA showed a slow-activating K+ current. Cells injected with KvLQT1 isoform 2 plasmid showed no detectable K+ current. Those injected with a 1/1 isoform 2/isoform 1 ratio showed no detectable K+ current. Those injected with 1/5 and 2/5 ratios showed a K+ current with markedly reduced amplitude. Coexpression of the IsK regulator consistently reduced the dominant negative effects of isoform 2. Our results indicate that KvLQT1 isoform 2 exerts a pronounced negative dominance on isoform 1 channels and that the cardiac KvLQT1 K+ channel complex is composed of at least three different proteins as follows: isoform 1, isoform 2, and IsK.

Published
1998

207. Overview of RFX-mod results with active MHD control

Author

PIERO MARTIN, Agostini, M., Alessi, C., Alfier, A., Antoni, V., Apolloni, L., Auriemma, F., PAOLO BETTINI, Bolzonella, T., Bonfiglio, D., Bonomo, F., Brombin, M., Buffa, Antonio, Canton, A., Cappello, S., Carraro, L., Cavazzana, R., Cavinato, M., Giuseppe Chitarin, Cravotta, A., Dal Bello, S., Lorenzi, A., Pasqual, L., Escande, D. F., Fassina, A., Franz, P., Gadani, G., Gaio, E., Garzotti, L., Gazza, Erica, LEONARDO GIUDICOTTI, Gnesotto, Francesco, Gobbin, M., Grando, L., Guo, S. C., Innocente, P., Lorenzini, R., Luchetta, A., Malesani, Gaetano, Manduchi, G., Marchiori, G., Marcuzzi, D., Marrelli, L., Martin, P., Martines, E., Masiello, A., Milani, F., Moresco, Maurizio, Murari, A., Novello, L., Ortolani, S., Paccagnella, R., Pasqualotto, R., Peruzzo, S., Piovan, R., Piovesan, P., Pizzimenti, A., Pomaro, N., Puiatti, M. E., Rostagni, Giorgio, Sattin, F., Scarin, P., Serianni, G., piergiorgio sonato, Spada, E., Soppelsa, A., Spizzo, G., Spolaore, M., Taccon, C., Taliercio, C., Terranova, D., Toigo, V., Valisa, M., Vianello, N., Zaccaria, P., Zanca, P., Zaniol, B., Zanotto, L., Zilli, Enrico, and GIUSEPPE ZOLLINO

209. Positive inotropic effects of RP 62719, a new pure class III antiarrhythmic agent, on guinea pig myocardium

Author

Jp, Beregi, Escande D, Coudray N, Mery P, Mestre M, Denis CHEMLA, and Lecarpentier Y

Subjects
Male, Potassium Channels, Piperidines, Guinea Pigs, Animals, Calcium, Chromans, In Vitro Techniques, Anti-Arrhythmia Agents, Myocardial Contraction, Stimulation, Chemical
Abstract

The mechanical effects of RP 62719 [(-)1-[-2-(3,4-dihydro-2H-1- benzopyran-4-yl)ethyl]-4-(3,4-dimethoxyphenyl)-piperidine] were tested in vitro on guinea pig left ventricular papillary muscle. RP 62719 is a novel pure class III antiarrhythmic agent known to prolong the cardiac action potential duration by selectively blocking the inward rectifying K+ current. Mechanical parameters were determined from contraction and relaxation phases under isotonic and isometric conditions. At a concentration of 0.02 microM, RP 62719 did not produce significant effects on inotropy or lusitropy. At 0.2 and 2 microM, the drug improved contraction under both heavy and low loading conditions, as evidenced by a 30% increase in maximum unloaded shortening velocity (Vmax, P.001), peak amplitude of shortening (delta L, P.001), peak isometric active force normalized per cross-sectional area (AF/s, P.001) and positive peak of the force derivative per mm2 (+dF/s, P.001). At the same concentrations, positive lusitropic effects were evidenced by an increase in maximum lengthening velocity (maxVr) and negative peak of force derivative per mm2 (-dF/s, P.001). At a higher concentration (20 microM), effects of RP 62719 on inotropy and lusitropy were less marked, thus accounting for the bell-shaped form of the dose-response curve. An increase in the extracellular Ca++ concentration from 2.5 to 3.75 mM improved inotropy to a similar extent (+30-50%) as did 2 microM RP 62719. However, lusitropy and mechanical coupling between contraction and relaxation were not modified in the same proportion under RP 62719 and under 3.75 mM Ca++.(ABSTRACT TRUNCATED AT 250 WORDS)

210. Edge transport properties of RFX-mod approaching the Greenwald density Limit

Author

Valisa, M., Frassinetti, L., Paccagnella, R., Puiatti, M. E., Sattin, F., Scarin, P., Spizzo, G., Spolaore, M., Vianello, N., Agostini, M., Alessi, C., Alfier, A., Antoni, V., Apolloni, L., Auriemma, F., PAOLO BETTINI, Bolzonella, T., Bonfiglio, D., Bonomo, F., Brombin, M., Buffa, Antonio, Canton, A., Cappello, S., Carraro, L., Cavazzana, R., Cavinato, M., Giuseppe Chitarin, Cravotta, A., Dal Bello, S., Lorenzi, A., Pasqual, L., Escande, D. F., Fassina, A., Franz, P., Gadani, G., Gaio, E., Garzotti, L., Gazza, Erica, LEONARDO GIUDICOTTI, Gnesotto, Francesco, Gobbin, M., Grando, L., Guo, S. C., Innocente, P., Lorenzini, R., Luchetta, A., Malesani, Gaetano, Manduchi, G., Marchiori, G., Marcuzzi, D., Marrelli, L., PIERO MARTIN, Martini, S., Martines, E., Masiello, A., Milani, F., Moresco, Maurizio, Novello, L., Ortolani, S., Pasqualotto, R., Peruzzo, S., Piovan, R., Piovesan, P., Pizzimenti, A., Pomaro, N., Predebon, I., Rostagni, Giorgio, Serianni, G., piergiorgio sonato, Spada, E., Soppelsa, A., Taccon, C., Taliercio, C., Terranova, D., Toigo, V., Zaccaria, P., Zanca, P., Zaniol, B., Zanotto, L., Zilli, E., GIUSEPPE ZOLLINO, Zuin Chengdu, M., and China Paper Submitted To Nf

213. TORE SUPRA TEAM MEMBERS 1988-2008

Author

Abgrall, R., Achard, M. H., Adam, J., Agarici, G., Agostini, E., Airaj, M., Albajar-Vinas, F., Allegretti, L., Allibert, J. P., Alliez, J. C., Allouche, A., Andreoletti, J., Ane, J. M., Angelino, P., Aniel, T., Antar, G., Arcis, N., Argouarch, A., Arnas, C., Arnoux, G., Arslanbekov, R., Artaud, J. F., Asp, E., Assas, S., Atttuel, G., Aymar, R., Azeroual, A., Balme, S., Barana, O., Bareyt, B., Basiuk, V., Basko, M., Bayetti, P., Baylor, L., Beaumont, B., Becherer, R., Becoulet, A., Becoulet, M., Begrambekov, L., Benkadda, S., Benoit, F., Bergeaud, V., Berger-By, G., Berio, S., Bernascolle, P., Bernier, N., Berroukeche, M., Bertrand, B., Bessette, D., Beyer, P., Bibet, P., Bizzaro, J., Blanchard, P., Blum, J., Boddeker, S., Boilson, D., Mardion, G. Bon, Bonnel, P., Bonnin, X., Boscary, J., Bosia, G., Bottereau, J. M., Bottiglioni, F., Bottollier-Curtet, H., Bouchand, C., Bouligand, G., Bouquey, F., Bourdelle, C., Bregeon, R., Bremond, F., Bremond, S., Breton, C., Breton, M., Brosset, C., Brugnetti, R., Bruneau, J. L., Bucalossi, J., Budny, R. V., Buravand, Y., Bush, C., Bussac, M. N., Cambe, A., Capes, H., Capitain, J. J., Cara, P., Carbonnier, J. L., Carpentier, S., Carrasco, J., Casati, A., Chaibi, O., Chamouard, C., Chantant, M., Chappuis, P., Chatain, D., Chatelier, E., Chatelier, M., Chatenet, J. H., Chen, X. P., Cherigier, L., Chevet, G., Chiarazzo, L., Ciazynski, D., Ciraolo, G., Cismondi, F., Clairet, F., Clary, J., Clement, C., Colas, L., Commaux, N., Corbel, E., Cordier, J. J., Corre, Y., Costanzo, L., Cote, A., Coulon, J. P., Courtois, L., Courtois, X., Couturier, B., Crenn, J. P., Cristofani, P., Crouseilles, N., Czarny, O., Rosa, P. Da Silva, Darbos, C., Darmet, G., Davi, M., Daviot, R., Esch, H., Gentile, B., Haas, J. C., La Cal, E., Michelis, C., Deck, C., Decker, J., Decool, P., Degond, P., Renaud Dejarnac, Delchambre, E., Delmas, E., Delpech, L., Demarthe, H., Dentan, M., Depret, G., Deschamps, P., Desgranges, C., Devynck, P., Doceul, L., Dolgetta, N., Doloc, C., Dong, Y., Dore, P., Douai, D., Dougnac, H., Drawin, H. W., Druaux, J., Druetta, M., Dubois, F., Dubois, M., Dubuit, N., Duchateau, J. L., Wit, T. Dudok, Dufour, E., Dumont, R., Dunand, G., Dupas, L., Duran, Y., Durocher, A., Edery, D., Ekedahl, A., Elbeze, D., Eriksson, L. G., Escande, D., Escarguel, A., Escourbiac, F., Evans, T., Faisse, F., Falchetto, G., Fall, T., Farge, M., Farjon, J. L., Faudot, E., Fazilleau, P., Fedorczak, N., Fenzi-Bonizec, C., Ferron, J. R., Fidone, I., Figarella, C., Fleurence, E., Fleury, I., Fois, M., Forrest, C., Foster, C. A., Fouquet, S., Fourment, C., Fraboulet, D., Francois, P., Franel, B., Frigione, D., Froissard, P., Fubiani, G., Fuchs, V., Fumelli, M., Gagey, B., Galindo, V., Gambier, D., Garampon, L., Garbet, X., Garbil, R., Garcia, J., Gardarein, J. L., Gargiulo, L., Garibaldi, P., Garin, P., Gauthier, E., Geraud, A., Gerbaud, T., Gervais, F., Geynet, M., Ghendrih, P., Gianakon, T., Giannella, R., Gil, C., Girard, J. P., Giruzzi, G., Godbert-Mouret, L., Gomez, P., Goniche, M., Gordeev, A., Granata, G., Grandgirard, V., Gravier, R., Gravil, B., Gregoire, M., Gregoire, S., Grelot, P., Gresillon, D., Grisolia, C., Gros, G., Grosman, A., Grua, P., Guerin, O., Guigon, R., Guilhem, D., Guillerminet, B., Guirlet, R., Guiziou, L., Gunn, J., Hacquin, S., Harris, J., Haste, G., Hatchressian, J. C., Hemsworth, R., Hennequin, P., Hennion, F., Hennion, V., Henry, D., Hernandez, C., Hertout, P., Hess, W., Hesse, M., Heuraux, S., Hillairet, J., Hoang, G. T., Hogan, J., Hong, S. H., Honore, C., Horton, L., Horton, W. W., Houlberg, W. A., Hourtoule, J., Houry, M., Houy, P., How, J., Hron, M., Hutter, T., Huynh, P., Huysmans, G., Idmtal, J., Imbeaux, F., Isler, R., Jaben, C., Jacquinot, J., Jacquot, C., Jager, B., Jaunet, M., Javon, C., Jelea, A., Jequier, F., Jie, Y. X., Jimenez, R., Joffrin, E., Johner, J., Jourd Heuil, L., Journeaux, J. Y., Joyer, P., Ju, M., Jullien, F., Junique, F., Kaye, S. M., Kazarian, F., Khodja, H., Klepper, C., Kocan, M., Koski, J., Krivenski, V., Krylov, A., Kupfer, K., Kuus, H., Labit, B., Laborde, L., Lacroix, B., Ladurelle, L., Lafon, D., Lamaison, V., Laporte, P., Lasalle, J., Latu, G., Laugier, F., Laurent, L., Lausenaz, Y., Laviron, C., Layet, J. M., Le Bris, A., Le Coz, F., Le Niliot, C., Lebris, A., Leclert, G., Lecoustey, P., Ledyankinc, A., Leloup, C., Lennholm, M., Leroux, F., Li, Y. Y., Libeyre, P., Linez, F., Lipa, M., Lippmann, S., Litaudon, X., Liu, W. D., Loarer, T., Lott, F., Lotte, P., Lowry, C., Luciani, J. F., Luetjens, H., Luty, J., Lutz, T., Lyraud, C., Maas, A., Macor, A., Madeleine, S., Magaud, P., Maget, P., Magne, R., Mahdavi, A., Mahe, F., Mailloux, J., Mandl, W., Manenc, L., Marandet, Y., Marbach, G., Marechal, J. L., Martin, C., Martin, G., Martin, V., Martinez, A., Martins, J. P., Maschke, E., Masse, L., Masset, R., Massmann, P., Mattioli, M., Mayaux, G., Mayoral, M. L., Mazon, D., Mcgrath, R., Mercier, C., Meslin, B., Meunier, L., Meyer, O., Michelot, Y., Million, L., Millot, P., Minguella, G., Minot, F., Mioduszewski, P., Misguich, J. H., Miskane, F., Missirlian, M., Mitteau, R., Moerel, F., Mollard, P., Monakhov, I., Moncada, V., Moncel, L., Monier-Garbet, P., Moreau, D., Moreau, F., Moreau, P., Morera, J. P., Moret, J. M., Moulin, B., Moulin, D., Mourgues, F., Moustier, M., Nakach, R., Nannini, M., Nanobashvili, I., Nardon, E., Navarra, P., Nehme, H., Nguyen, C., Nguyen, F., Nicollet, S., Nygren, R., Ogorodnikova, O., Olivain, J., Orlandelli, P., Ottaviani, M., Ouvrier-Buffet, P., Ouyang, Z., Owen, L., Pacella, D., Pain, M., Pamela, J., Pamela, S., Panek, R., Panzarella, A., Paris, R., Parisot, T., Park, S. H., Parlange, F., Parrat, H., Pastor, G., Pastor, P., Pastor, T., Patris, R., Paume, M., Payan, J., Pecquet, A. L., Pegourie, B., Petrov, Y., Petrzilka, V., Peysson, Y., Piat, D., Picchiottino, J. M., Pierre, J., Platz, P., Portafaix, C., Prou, M., Pugno, R., Putchy, L., Qin, C. M., Quallis, L., Quemeneur, A., Quet, P., Rabaglino, E., Raharijaona, J. J., Ramette, J., Ravenel, N., Rax, J. M., Reichle, R., Renard, B., Renner, H., Reuss, J. D., Reux, C., Reverdin, C., Rey, G., Reynaud, P., Riband, P. H., Richou, M., Rigollet, F., Rimini, F., Riquet, D., Rochard, F., Rodriguez, L., Romanelli, M., Romannikov, A., Rosanvallon, S., Roth, J., Rothan, B., Roubin, J. P., Roubin, P., Roupillard, G., Roussel, P., Ruggieri, R., Sabathier, F., Sabbagh, S. A., Sabot, R., Saha, S. K., Saint-Laurent, F., Salasca, S., Salmon, T., Salvador, J., Samaille, F., Samain, A., Santagiustina, A., Saoutic, B., Sarazin, Y., Schild, T., Schlosser, J., Schneider, M., Schneider, K., Schunke, B., Schwander, F., Schwob, J. L., Sebelin, E., Segui, J. L., Seigneur, A., Shepard, T., Shigin, P., Signoret, J., Simoncini, J., Simonet, F., Simonin, A., Sirinelli, A., Sledziewski, Z., Smits, F., Soler, K., Sonato, P. G., Song, S. D., Sonnendrucker, E., Sourd, F., Spitz, P., Spuig, P., Stamm, R., Stephan, Y., Stirling, W., Stockel, J., Stott, P., Sthal, K. Strom, Surle, F., Svensson, L., Tachon, J., Talvard, M., Tamain, P., Tavian, L., Tena, M., Theis, J. M., Thomas, C. E., Thomas, P., Thonnat, M., Tobin, S., Tokar, M., Tonon, G., Torossian, A., Torre, A., Trainham, R. C., Travere, J. M., Tresset, G., Trier, E., Truc, A., Tsitrone, E., Turck, B., Turco, F., Turlur, S., Uckan, T., Udintsev, V., Urguijo, G., Utzel, N., Vallet, J. C., Valter, J., Houtte, D., Rompuy, T., Vatry, A., Verga, A., Vermare, L., Vezard, D., Viallet, H., Villecroze, F., Villedieu, E., Villegas, D., Vincent, E., Voitsekovitch, I., Hellermann, M., Voslamber, D., Voyer, D., Vulliez, K., Wachter, C., Wagner, T., Waller, V., Wang, G., Wang, Z., Watkins, J., Weisse, J., White, R., Wijnands, T., Witrant, E., Worms, J., Xiao, W., Yu, D., Zabeo, L., Zabiego, M., Zani, L., Zhuang, G., Zou, X. L., Zucchi, E., Zunino, K., Zwingmann, W., and Tore Supra, Team

214. First results on reversed field pinch plasmas with new magnetic boundary in the RFX-mod experiment

Author

Agostini, M., Alfier, A., Antoni, V., Apolloni, L., Auriemma, F., Bagatin, M., Baker, W., Barana, O., Basso, F., Bettini, P., Bolzonella, T., Bonfiglio, D., Bonomo, F., Buffa, A., Canton, A., Cappello, S., Carraro, L., Cavazzana, R., Cavinato, M., Chitarin, G., Cravotta, A., Dal Bello, F. S., Dalla Palma, M., Lorenzi, A., Pasqual, L., Desideri, D., Escande, D. F., Franz, P., Gadani, G., Gaio, E., Garzotti, L., Gazza, E., Giudicotti, L., Gnesotto, F., Gobbin, M., Grando, L., Guo, S. C., Innocente, P., Lorenzini, R., Luchetta, A., Malesani, G., Manduchi, G., Marchiori, G., Marcuzzi, D., Lionello Marrelli, Martin, P., Martines, E., Martini, S., Masiello, A., Milani, F., Moresco, M., Murari, A., Nielsen, P., Ortolani, S., Paccagnella, R., Pasqualotto, R., Peruzzo, S., Piovan, R., Piovesan, P., Pomaro, N., Predebon, I., Puiatti, M. E., Rostagni, G., Sattin, F., Scarin, P., Schmidt, V., Serianni, G., Sonato, P., Spada, E., Spizzo, G., Spolaore, M., Taccon, C., Taliercio, C., Terranova, D., Toigo, V., Valisa, M., Vianello, N., Zaccaria, P., Zanca, P., Zaniol, B., Zanotto, L., Zilli, E., Zollino, G., and Zuin, M.

217. First results on Reversed Field Pinch plasmas with new magnetic plasma boundary in the RFX experiment

Author

Martini, S., Innocente, P., Agostini, M., Alfier, A., Antoni, V., Apolloni, L., Auriemma, F., Bagatin, M., Baker, W., Barana, O., Basso, F., PAOLO BETTINI, Bolzonella, T., Bonfiglio, D., Bonomo, F., Buffa, Antonio, Canton, A., Cappello, S., Cavazzana, L. Carraro R., Cavinato, M., Giuseppe Chitarin, Cravotta, A., Dal Bello, F. S., Dalla Palma, M., Lorenzi, A., Pasqual, Lucia, DANIELE DESIDERI, Escande, D. F., Franz, P., Gadani, G., Gaio, E., Garzotti, L., Gazza, E., LEONARDO GIUDICOTTI, Gnesotto, Francesco, Gobbin, M., Grando, L., Guo, S. C., Lorenzini, R., Luchetta, A., Malesani, Gaetano, Manduchi, G., Marchiori, G., Marcuzzi, D., Marrelli, L., PIERO MARTIN, Martines, E., Masiello, A., Milani, F., Moresco, Maurizio, Murari, A., Nielsen, P., Ortolani, S., Paccagnella, R., Pasqualotto, R., Peruzzo, S., Piovan, R., Piovesan, P., Predebon, I., Pomaro, N., Puiatti, M. E., Rostagni, Giorgio, Sattin, F., Scarin, P., Schmidt, V., Serianni, G., piergiorgio sonato, Spada, E., Spizzo, G., Spolaore, M., Taccon, C., Taliercio, C., Terranova, D., Toigo, V., Valisa, M., Vianello, N., Zaccaria, P., Zanca, P., Zaniol, B., Zanotto, L., Zilli, Enrico, GIUSEPPE ZOLLINO, and Zuin, M.

219. Interspecies differences in the cardiac negative inotropic effects of beta(3)-adrenoceptor agonists

Author

Gauthier C, Geneviève Tavernier, Jn, Trochu, Leblais V, Laurent K, Langin D, Escande D, and Le Marec H

Subjects
Male, Reverse Transcriptase Polymerase Chain Reaction, Guinea Pigs, Ferrets, Adrenergic beta-Agonists, In Vitro Techniques, Papillary Muscles, Myocardial Contraction, Rats, Dogs, Species Specificity, Depression, Chemical, Receptors, Adrenergic, beta-3, Receptors, Adrenergic, beta, Animals, Humans, RNA, Messenger, Rats, Wistar
Abstract

The aim of the present study was to compare the effects of three preferential (BRL 37344, SR 58611, CL 316 243) and a partial (CGP 12177) beta-adrenoceptor (beta(3)-AR) agonists on the contractility of ventricular strips sampled from various mammalian species including humans. In the human heart, all beta(3)-AR agonists tested decreased contractility by 40 to 60% below control with an order of potency: BRL 37344CL 316 243 = SR 58611CGP 12177. In the dog, the negative inotropic effects produced by beta(3)-AR stimulation were less pronounced than in humans, approximately 30% below control. The order of potency of beta(3)-AR agonists was CGP 12177BRL 37344 = SR 58611CL 316 243; i.e., very different from that observed in humans. In rat, only BRL 37344 was efficient to decrease contractility. In guinea pig, only CL 316 243 significantly reduced peak tension. In both species, the reduction in peak tension did not exceed 20 to 30%. Finally, in the ferret, none of the agonists tested induced a negative inotropic effect. In dog, the negative inotropic effects of CGP 12177 were not modified by nadolol, but were abolished by bupranolol, a beta(1-3)-AR. beta(3)-AR transcripts were detected in the dog but not in the rat ventricle by using a reverse transcription-polymerase chain reaction assay. We conclude that cardiac negative inotropic effects related to beta(3)-AR agonist stimulation vary markedly depending on the species. A comparable interspecies variation previously has been reported concerning the lipolytic effects of beta(3)-AR agonist stimulation. Our study demonstrates that the pharmacological profile of a beta(3)-AR agonist on the human myocardium cannot be extrapolated from usual animal models.

220. THEORY AND EXPERIMENTS ON RF PLASMA-HEATING, CURRENT DRIVE AND PROFILE CONTROL IN TORE-SUPRA

Author

Moreau, D., Agarici, G., Allibert, Jp, Ane, Jm, Arslanbekov, R., Balme, S., Bareyt, B., Basiuk, V., Bayetti, P., Beaumont, B., Becherer, R., Becoulet, A., Benkadda, M., Bergerby, G., Bessette, D., Bibet, P., Bizarro, Jp, Bonmardion, G., Bonnel, P., Bottereau, Jm, Bottiglioni, F., Bremond, S., Brugnetti, R., Budny, Rv, Buravand, Y., Capes, H., Capitain, Jj, Carbonnier, Jl, Carrasco, J., Chappuis, P., Chatain, D., Chatelier, E., Chatelier, M., Chatenet, Jh, Chen, Xp, Chinardet, J., Ciazynski, D., Clairet, F., Colas, L., Cordier, Jj, Cote, A., Coulon, Jp, Couturier, B., Crenn, Jp, Cristofani, P., Deck, C., Decool, P., Degentile, B., Demarthe, H., Dehas, Jc, Demichelis, C., Deschamps, P., Desgranges, C., Devynck, P., Doceul, L., Doloc, C., Dougnac, M., Drawin, Hw, Druetta, M., Dubois, M., Duchateau, Jl, Dewit, Td, Dupas, L., Edery, D., Elbeze, D., Escande, D., Farjon, Jl, Fidone, I., Fois, M., Foster, Ca, Fraboulet, D., Fuchs, V., Fumelli, M., Gagey, B., Garampon, L., Garbet, X., Gauthier, E., Geraud, A., Gervais, F., Ghendrih, P., Gil, C., Giruzzi, G., Goniche, M., Gravier, R., Gravil, B., Gregoire, M., Gresillon, D., Grisolia, C., Grosman, A., Guilhem, D., Guillerminet, B., Guirlet, R., Guiziou, L., Harris, G., Harris, J., Harvey, R., Haste, G., Hennequin, P., Hennion, F., Hertout, P., Hess, Wr, Hesse, M., Hoang, Gt, Hogans, J., Hutter, T., Idmtal, J., Jacquot, C., Jager, B., Jequier, F., Joffrin, E., Johner, J., Journeaux, Jy, Joyer, P., Stanley Kaye, Klepper, C., Kazarian, F., Kupfer, K., Kuus, H., Lafon, D., Laporte, P., Lasalle, J., Laurent, L., Laviron, C., Leclert, G., Lecoustey, P., Ledyankine, A., Leloup, C., Li, Yy, Libeyre, P., Lipa, M., Lippmann, S., Litaudon, X., Liu, Wd, Loarer, T., Lotte, P., Luciani, Jf, Mcgrath, R., Magaud, P., Magne, R., Martin, G., Martinez, A., Maschke, Ek, Masset, R., Mattioli, M., Mayaux, G., Michelot, Y., Mioduszewski, P., Misguich, J., Mollard, P., Moniergarvet, P., Moreau, F., Morera, Jp, Moulin, B., Moulin, D., Moustier, M., Nakach, R., Nguyen, F., Ouvrierbuffet, P., Owen, L., Pain, M., Pamela, J., Parlange, F., Pastor, G., Patris, R., Paume, M., Payan, J., Pecquet, Al, Pegourie, B., Peysson, Y., Piat, D., Picchiottino, Jm, Platz, P., Portafaix, C., Prou, M., Quemeneur, A., Rax, Jm, Rey, C., Riband, P., Rothan, B., Roussel, P., Sabbagh, Sa, Saha, Sk, Samaille, F., Samain, A., Saoutic, B., Schlosser, J., Seigneur, A., Segui, Jl, Smits, F., Soler, K., Stephan, Y., Tachon, J., Talvard, M., Theis, Jm, Thomas, Ce, Tobin, S., Tonon, G., Torossian, A., Truc, A., Tsitrone, E., Turck, B., Turlur, S., Uckan, T., Urquijo, G., Vallet, Jc, Valter, J., Vanhoutte, D., Verga, A., Vezard, D., Viallet, H., Watkins, J., Weisse, J., White, R., Wijnands, T., Zabiego, M., and Zou, Xl

221. Helical flow in the RFX-mod reversed field pinch experiment

Author

Spolaore, M., MATTEO AGOSTINI, Bonfiglio, D., Bonomo, F., Cappello, S., Carraro, L., Masi, G., Escande, D. F., Gobbin, M., Innocente, P., Marrelli, L., Martines, E., Momo, B., Piovesan, P., Scarin, P., Spizzo, G., Vianello, N., and Zaniol, B.

237. Uniform derivation of Coulomb collisional transport thanks to Debye shielding.

Author

Escande, D. F., Elskens, Yves, and Doveil, F.

Subjects
*DEBYE length, *PLASMA physics, *RUTHERFORD scattering, *STOCHASTIC convergence, *THERMODYNAMIC equilibrium
Abstract

The effective potential acting on particles in plasmas being essentially the Debye-shielded Coulomb potential, the particles collisional transport in thermal equilibrium is calculated for all impact parameters b, with a convergent expression reducing to Rutherford scattering for small b. No cutoff at the Debye length scale is needed, and the Coulomb logarithm is only slightly modified. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

244. Overview of the RFX fusion science program

Author

M. Gobbin, Roberto Pasqualotto, D. Bonfiglio, Enrico Zilli, Giuseppe Marchiori, Piero Martin, S. Martini, Fulvio Auriemma, E. Gazza, D.K. Mansfield, P. Zaccaria, Piergiorgio Sonato, S. Ortolani, Wolf-Dieter Schneider, D. Yadikin, Stefano Munaretto, L. Piron, M. Valisa, Fabio Sattin, Susanna Cappello, G. V. Perverezev, F. Milani, Roberto Paccagnella, Paolo Bettini, S. Fiameni, Roscoe White, A. Ruzzon, V. Antoni, Leonardo Giudicotti, Yueqiang Liu, Lionello Marrelli, Nicola Vianello, S. Dal Bello, A. Scaggion, V. Rigato, Fabio Villone, A. Zamengo, Federica Bonomo, R. Cavazzana, M. Baruzzo, L. Carraro, F. Fantini, Giuseppe Zollino, Barbara Zaniol, Rita Lorenzini, Luis Chacon, X. Garbet, C. Angioni, Andrea Rizzolo, G. De Masi, G. Rostagni, W. A. Cooper, Manabu Takechi, Piero Agostinetti, Paolo Scarin, A. Pizzimenti, Yongkyoon In, Sheena Menmuir, Silvia Spagnolo, M. Moresco, Satoru Kiyama, S. P. Hirshman, M. Okabayashi, Giuseppe Chitarin, S. C. Guo, Gabriele Manduchi, Dominique Escande, Gianluigi Serianni, Alessandro Fassina, Luca Grando, Simona Barison, Allen H. Boozer, Michael Drevlak, Diego Marcuzzi, M. Pavei, J.Q. Dong, Anton Soppelsa, B. Momo, Gianluca Spizzo, Hajime Sakakita, Neil Pomphrey, Shunsuke Ide, Donald A. Spong, J. S. Sarff, Alessandra Canton, D. Lopez Bruna, M. Brombin, Matteo Zuin, T. Bolzonella, R. Piovan, Songfen Liu, Alberto Ferro, Italo Predebon, V. Igochine, L. Zanotto, Simone Peruzzo, Elena Gaio, P. Piovesan, Cesare Taliercio, J. Adamek, Go Matsunaga, P. Zanca, A. Buffa, M. Veranda, N. Pomaro, M. Spolaore, Oliviero Barana, Francesco Gnesotto, Emilio Martines, M. Dalla Palma, Paolo Franz, David Terranova, Yoichi Hirano, Matteo Agostini, G. Mazzitelli, Alberto Alfier, L. Novello, Vanni Toigo, M. Boldrin, R. Delogu, Guglielmo Rubinacci, Maria Ester Puiatti, A. Fiorentin, Karsten McCollam, E. Spada, M. Cavinato, A. De Lorenzi, L. Apolloni, J. Brotankova, F. Fellin, P. Innocente, Raul Sanchez, Zhirui Wang, Adriano Luchetta, Martin, P, Adamek, J, Agostinetti, P, Agostini, M, Alfier, A, Angioni, C, Antoni, V, Apolloni, L, Auriemma, F, Barana, O, Barison, S, Baruzzo, M, Bettini, P, Boldrin, M, Bolzonella, T, Bonfiglio, D, Bonomo, F, Boozer, A, Brombin, M, Brotankova, J, Buffa, A, Canton, A, Cappello, S, Carraro, L, Cavazzana, R, Cavinato, M, Chacon, L, Chitarin, G, Cooper, W, Dal Bello, S, Dalla Palma, M, Delogu, R, De Lorenzi, A, De Masi, G, Dong, J, Drevlak, M, Escande, D, Fantini, F, Fassina, A, Fellin, F, Ferro, A, Fiameni, S, Fiorentin, A, Franz, P, Gaio, E, Garbet, X, Gazza, E, Giudicotti, L, Gnesotto, F, Gobbin, M, Grando, L, Guo, S, Hirano, Y, Hirshman, S, Ide, S, Igochine, V, In, Y, Innocente, P, Kiyama, S, Liu, S, Liu, Y, Bruna, D, Lorenzini, R, Luchetta, A, Manduchi, G, Mansfield, D, Marchiori, G, Marcuzzi, D, Marrelli, L, Martini, S, Matsunaga, G, Martines, E, Mazzitelli, G, Mccollam, K, Menmuir, S, Milani, F, Momo, B, Moresco, M, Munaretto, S, Novello, L, Okabayashi, M, Ortolani, S, Paccagnella, R, Pasqualotto, R, Pavei, M, Perverezev, G, Peruzzo, S, Piovan, R, Piovesan, P, Piron, L, Pizzimenti, A, Pomaro, N, Pomphrey, N, Predebon, I, Puiatti, M, Rigato, V, Rizzolo, A, Rostagni, G, Rubinacci, G, Ruzzon, A, Sakakita, H, Sanchez, R, Sarff, J, Sattin, F, Scaggion, A, Scarin, P, Schneider, W, Serianni, G, Sonato, P, Spada, E, Soppelsa, A, Spagnolo, S, Spolaore, M, Spong, D, Spizzo, G, Takechi, M, Taliercio, C, Terranova, D, Toigo, V, Valisa, M, Veranda, M, Vianello, N, Villone, F, Wang, Z, White, R, Yadikin, D, Zaccaria, P, Zamengo, A, Zanca, P, Zaniol, B, Zanotto, L, Zilli, E, Zollino, G, Zuin, M, Martin, P., Adamek, J., Agostinetti, P., Agostini, M., Alfier, A., Angioni, C., Antoni, V., Apolloni, L., Auriemma, F., Barana, O., Barison, S., Baruzzo, M., Bettini, P., Boldrin, M., Bolzonella, T., Bonfiglio, D., Bonomo, F., Boozer, A. H., Brombin, M., Brotankova, J., Buffa, A., Canton, A., Cappello, S., Carraro, L., Cavazzana, R., Cavinato, M., Chacon, L., Chitarin, G., Cooper, W. A., Bello, S. D., Palma, M. D., Delogu, R., Lorenzi, A. D., Masi, G. D., Dong, J. Q., Drevlak, M., Escande, D. F., Fantini, F., Fassina, A., Fellin, F., Ferro, A., Fiameni, S., Fiorentin, A., Franz, P., Gaio, E., Garbet, X., Gazza, E., Giudicotti, L., Gnesotto, F., Gobbin, M., Grando, L., Guo, S. C., Hirano, Y., Hirshman, S. P., Ide, S., Igochine, V., In, Y., Innocente, P., Kiyama, S., Liu, S. F., Liu, Y. Q., Bruna, D. L., Lorenzini, R., Luchetta, A., Manduchi, G., Mansfield, D. K., Marchiori, G., Marcuzzi, D., Marrelli, L., Martini, S., Matsunaga, G., Martines, E., Mazzitelli, G., Mccollam, K., Menmuir, S., Milani, F., Momo, B., Moresco, M., Munaretto, S., Novello, L., Okabayashi, M., Ortolani, S., Paccagnella, R., Pasqualotto, R., Pavei, M., Perverezev, G. V., Peruzzo, S., Piovan, R., Piovesan, P., Piron, L., Pizzimenti, A., Pomaro, N., Pomphrey, N., Predebon, I., Puiatti, M. E., Rigato, V., Rizzolo, A., Rostagni, G., Rubinacci, Guglielmo, Ruzzon, A., Sakakita, H., Sanchez, R., Sarff, J. S., Sattin, F., Scaggion, A., Scarin, P., Schneider, W., Serianni, G., Sonato, P., Spada, E., Soppelsa, A., Spagnolo, S., Spolaore, M., Spong, D. A., Spizzo, G., Takechi, M., Taliercio, C., Terranova, D., Toigo, V., Valisa, M., Veranda, M., Vianello, N., Villone, F., Wang, Z., White, R. B., Yadikin, D., Zaccaria, P., Zamengo, A., Zanca, P., Zaniol, B., Zanotto, L., Zilli, E., Zollino, G., and Zuin, M.

Subjects
Nuclear and High Energy Physics, RFX-mod, Tokamak, Nuclear engineering, PLASMAS, CONFINEMENT, reversed field pinch, magnetic confinement, law.invention, law, Physics::Plasma Physics, RFP, Scaling, Mod, Physics, Reversed field pinch, STABILITY, Magnetic confinement fusion, INTERNAL TRANSPORT BARRIER, Plasma, Fusion power, Condensed Matter Physics, REVERSED-FIELD-PINCH, Atomic physics, Magnetohydrodynamics, Stellarator
Abstract

This paper summarizes the main achievements of the RFX fusion science program in the period between the 2008 and 2010 IAEA Fusion Energy Conferences. RFX-mod is the largest reversed field pinch in the world, equipped with a system of 192 coils for active control of MHD stability. The discovery and understanding of helical states with electron internal transport barriers and core electron temperature >1.5 keV significantly advances the perspectives of the configuration. Optimized experiments with plasma current up to 1.8 MA have been realized, confirming positive scaling. The first evidence of edge transport barriers is presented. Progress has been made also in the control of first-wall properties and of density profiles, with initial first-wall lithization experiments. Micro-turbulence mechanisms such as ion temperature gradient and micro-tearing are discussed in the framework of understanding gradient-driven transport in low magnetic chaos helical regimes. Both tearing mode and resistive wall mode active control have been optimized and experimental data have been used to benchmark numerical codes. The RFX programme also provides important results for the fusion community and in particular for tokamaks and stellarators on feedback control of MHD stability and on three-dimensional physics. On the latter topic, the result of the application of stellarator codes to describe three-dimensional reversed field pinch physics will be presented. © 2011 IAEA, Vienna.

Published
2011

245. Overview of RFX-mod results

Author

R. Paccagnella, Cesare Taliercio, J. Adamek, V. Antoni, A. Pizzimenti, Gianluca Spizzo, Gabriele Manduchi, E. Spada, Vanni Toigo, D. Terranova, Alberto Ferro, N. Pomaro, P. Zaccaria, Rita Lorenzini, B. E. Chapman, Piero Martin, L. Guazzotto, A. Zamengo, Simone Peruzzo, Elena Gaio, Italo Predebon, V. Igochine, F. Milani, M. Spolaore, Oliviero Barana, Francesco Gnesotto, Alessandro Fassina, Giuseppe Marchiori, E. Gazza, G. Serianni, L. Zanotto, Piergiorgio Sonato, L. Piron, A. De Lorenzi, Diego Marcuzzi, Alessandra Canton, Matteo Zuin, T. Bolzonella, Federica Bonomo, Fabio Villone, M. Valisa, S. Cappello, H. Zohm, R. Cavazzana, J. Brotankova, Maria Ester Puiatti, M. Gobbin, P. Scarin, P. Zanca, Silvia Spagnolo, M. Baruzzo, Lionello Marrelli, Fabio Sattin, A. Buffa, Nicola Vianello, Fulvio Auriemma, Karsten McCollam, S. Ortolani, J. S. Sarff, S. Dal Bello, M. Cavinato, Paolo Bettini, P. Piovesan, G. Rostagni, P. Innocente, P. Buratti, M. Moresco, Roscoe White, Leonardo Giudicotti, Anton Soppelsa, Guglielmo Rubinacci, Sheena Menmuir, Emilio Martines, Paolo Franz, L. Carraro, D. Bonfiglio, Enrico Zilli, S. Martini, G. De Masi, L. Apolloni, Giuseppe Chitarin, M. Brombin, R. Piovan, Matteo Agostini, J.A. Reusch, Barbara Zaniol, Yueqiang Liu, S. C. Guo, Dominique Escande, S.V. Annibaldi, Alberto Alfier, L. Novello, Luca Grando, Adriano Luchetta, Roberto Pasqualotto, D. Yadikin, Martin, P, Apolloni, L, Puiatti, M, Adamek, J, Agostini, M, Alfier, A, Annibaldi, S, Antoni, V, Auriemma, F, Barana, O, Baruzzo, M, Bettini, P, Bolzonella, T, Bonfiglio, D, Bonomo, F, Brombin, M, Brotankova, J, Buffa, A, Buratti, P, Canton, A, Cappello, S, Carraro, L, Cavazzana, R, Cavinato, M, Chapman, B, Chitarin, G, Dal Bello, S, De Lorenzi, A, De Masi, G, Escande, D, Fassina, A, Ferro, A, Franz, P, Gaio, E, Gazza, E, Giudicotti, L, Gnesotto, F, Gobbin, M, Grando, L, Guazzotto, L, Guo, S, Igochine, V, Innocente, P, Liu, Y, Lorenzini, R, Luchetta, A, Manduchi, G, Marchiori, G, Marcuzzi, D, Marrelli, L, Martini, S, Martines, E, Mccollam, K, Menmuir, S, Milani, F, Moresco, M, Novello, L, Ortolani, S, Paccagnella, R, Pasqualotto, R, Peruzzo, S, Piovan, R, Piovesan, P, Piron, L, Pizzimenti, A, Pomaro, N, Predebon, I, Reusch, J, Rostagni, G, Rubinacci, G, Sarff, J, Sattin, F, Scarin, P, Serianni, G, Sonato, P, Spada, E, Soppelsa, A, Spagnolo, S, Spolaore, M, Spizzo, G, Taliercio, C, Terranova, D, Toigo, V, Valisa, M, Vianello, N, Villone, F, White, R, Yadikin, D, Zaccaria, P, Zamengo, A, Zanca, P, Zaniol, B, Zanotto, L, Zilli, E, Zohm, H, Zuin, M, Martin, P., Apolloni, L., Puiatti, M. E., Adamek, J., Agostini, M., Alfier, A., Annibaldi, S. V., Antoni, V., Auriemma, F., Barana, O., Baruzzo, M., Bettini, P., Bolzonella, T., Bonfiglio, D., Bonomo, F., Brombin, M., Brotankova, J., Buffa, A., Buratti, P., Canton, A., Cappello, S., Carraro, L., Cavazzana, R., Cavinato, M., Chapman, B. E., Chitarin, G., Dal Bello, S., De Lorenzi, A., De Masi, G., Escande, D. F., Fassina, A., Ferro, A., Franz, P., Gaio, E., Gazza, E., Giudicotti, L., Gnesotto, F., Gobbin, M., Grando, L., Guazzotto, L., Guo, S. C., Igochine, V., Innocente, P., Liu, Y. Q., Lorenzini, R., Luchetta, A., Manduchi, G., Marchiori, G., Marcuzzi, D., Marrelli, L., Martini, S., Martines, E., Mccollam, K., Menmuir, S., Milani, F., Moresco, M., Novello, L., Ortolani, S., Paccagnella, R., Pasqualotto, R., Peruzzo, S., Piovan, R., Piovesan, P., Piron, L., Pizzimenti, A., Pomaro, N., Predebon, I., Reusch, J. A., Rostagni, G., Rubinacci, Guglielmo, Sarff, J. S., Sattin, F., Scarin, P., Serianni, G., Sonato, P., Spada, E., Soppelsa, A., Spagnolo, S., Spolaore, M., Spizzo, G., Taliercio, C., Terranova, D., Toigo, V., Valisa, M., Vianello, N., Villone, F., White, R. B., Yadikin, D., Zaccaria, P., Zamengo, A., Zanca, P., Zaniol, B., Zanotto, L., Zilli, E., Zohm, H., and Zuin, M.

Subjects
Physics, Nuclear and High Energy Physics, Leading edge, Tokamak, RFX-mod, Reversed field pinch, MHD, magnetic confinement, Magnetic confinement fusion, reversed field pinch, Fusion power, Condensed Matter Physics, TRANSPORT, law.invention, LUNDQUIST NUMBER, Nuclear physics, REVERSED-FIELD-PINCH, EDGE, law, RFP, Electron temperature, Magnetohydrodynamics, Plasma stability
Abstract

With the exploration of the MA plasma current regime in up to 0.5 s long discharges, RFX-mod has opened new and very promising perspectives for the reversed field pinch (RFP) magnetic configuration, and has made significant progress in understanding and improving confinement and in controlling plasma stability. A big leap with respect to previous knowledge and expectations on RFP physics and performance has been made by RFX-mod since the last 2006 IAEA Fusion Energy Conference. A new self-organized helical equilibrium has been experimentally achieved (the Single Helical Axis - SHAx - state), which is the preferred state at high current. Strong core electron transport barriers characterize this regime, with electron temperature gradients comparable to those achieved in tokamaks, and by a factor of 4 improvement in confinement time with respect to the standard RFP. RFX-mod is also providing leading edge results on real-time feedback control of MHD instabilities, of general interest for the fusion community. © 2009 IAEA, Vienna.

Published
2009

246. Impact of helical boundary conditions on nonlinear 3D magnetohydrodynamic simulations of reversed-field pinch.

Author

Veranda, M., Bonfiglio, D., Cappello, S., Chacón, L., and Escande, D. F.

Subjects
*BOUNDARY value problems, *NONLINEAR systems, *MAGNETOHYDRODYNAMICS, *SYMMETRY (Physics), *COMPUTER simulation, *NUMERICAL analysis, *PLASMA gases
Abstract

Helical self-organized reversed-field pinch (RFP) regimes emerge both numerically--in 3D visco-resistive magnetohydrodynamic (MHD) simulations--and experimentally, as in the RFX-mod device at high current (IP above 1 MA). These states, called quasi-single helicity (QSH) states, are characterized by the action of a MHD mode that impresses a quasi-helical symmetry to the system, thus allowing a high degree of magnetic chaos healing. This is in contrast with the multiple helicity (MH) states, where magnetic fluctuations create a chaotic magnetic field degrading the confinement properties of the RFP. This paper reports an extensive numerical study performed in the frame of 3D visco-resistive MHD which considers the effect of helical magnetic boundary conditions, i.e. of a finite value of the radial magnetic field at the edge (magnetic perturbation, MP). We show that the system can be driven to a selected QSH state starting from both spontaneous QSH and MH regimes. In particular, a high enough MP can force a QSH helical self-organization with a helicity different from the spontaneous one. Moreover, MH states can be turned into QSH states with a selected helicity. A threshold in the amplitude of MP is observed above which is able to influence the system. Analysis of the magnetic topology of these simulations indicates that the dominant helical mode is able to temporarily sustain conserved magnetic structures in the core of the plasma. The region occupied by conserved magnetic surfaces increases reducing secondary modes' amplitude to experimental-like values. [ABSTRACT FROM AUTHOR]

Published
2013
Full Text
View/download PDF

247. Quasilinear transport modelling at low magnetic shear.

Author

Citrin, J., Bourdelle, C., Cottier, P., Escande, D. F., Gürcan, Ö. D., Hatch, D. R., Hogeweij, G. M. D., Jenko, F., and Pueschel, M. J.

Subjects
*QUASILINEARIZATION, *TRANSPORT theory, *MATHEMATICAL models, *SHEAR (Mechanics), *MAGNETIC fields, *PREDICTION models, *SIMULATION methods & models, *NONLINEAR theories
Abstract

Accurate and computationally inexpensive transport models are vital for routine and robust predictions of tokamak turbulent transport. To this end, the QuaLiKiz [Bourdelle et al., Phys. Plasmas 14, 112501 (2007)] quasilinear gyrokinetic transport model has been recently developed. QuaLiKiz flux predictions have been validated by non-linear simulations over a wide range in parameter space. However, a discrepancy is found at low magnetic shear, where the quasilinear fluxes are significantly larger than the non-linear predictions. This discrepancy is found to stem from two distinct sources: the turbulence correlation length in the mixing length rule and an increase in the ratio between the quasilinear and non-linear transport weights, correlated with increased non-linear frequency broadening. Significantly closer agreement between the quasilinear and non-linear predictions is achieved through the development of an improved mixing length rule, whose assumptions are validated by non-linear simulations. [ABSTRACT FROM AUTHOR]

Published
2012
Full Text
View/download PDF

248. Self-organized helical equilibria as a new paradigm for ohmically heated fusion plasmas.

Author

Lorenzini, R., Martines, E., Piovesan, P., Terranova, D., Zanca, P., Zuin, M., Alfier, A., Bonfiglio, D., Bonomo, F., Canton, A., Cappello, S., Carraro, L., Cavazzana, R., Escande, D. F., Fassina, A., Franz, P., Gobbin, M., Innocente, P., Marrelli, L., and Pasqualotto, R.

Subjects
*FUSION reactors, *TOPOLOGY
Abstract

In the quest for new energy sources, the research on controlled thermonuclear fusion has been boosted by the start of the construction phase of the International Thermonuclear Experimental Reactor (ITER). ITER is based on the tokamak magnetic configuration, which is the best performing one in terms of energy confinement. Alternative concepts are however actively researched, which in the long term could be considered for a second generation of reactors. Here, we show results concerning one of these configurations, the reversed-field pinch (RFP). By increasing the plasma current, a spontaneous transition to a helical equilibrium occurs, with a change of magnetic topology. Partially conserved magnetic flux surfaces emerge within residual magnetic chaos, resulting in the onset of a transport barrier. This is a structural change and sheds new light on the potential of the RFP as the basis for a low-magnetic-field ohmic fusion reactor. [ABSTRACT FROM AUTHOR]

Published
2009
Full Text
View/download PDF

249. RFP based Fusion-Fission Hybrid reactor model for nuclear applications

Author

Marco Ripani, Giuseppe Zollino, M. Zuin, Paolo Bettini, Piero Agostinetti, R. Casagrande, M. E. Puiatti, Chiara Bustreo, M. Osipenko, Roberto Cavazzana, Fabio Panza, Giovanni Ricco, M. Valisa, D.F. Escande, R. Piovan, Bustreo, C., Agostinetti, P., Bettini, P., Casagrande, R., Cavazzana, R., Escande, D., Osipenko, M., Panza, F., Piovan, R., Puiatti, M. E., Ricco, G., Ripani, M., Valisa, M., Zollino, G., and Zuin, M.

Subjects
Materials science, Nuclear fuel cladding, Nuclear transmutation, Nuclear fuel, Reversed field pinch, Mechanical Engineering, Nuclear engineering, Blanket, 01 natural sciences, 010305 fluids & plasmas, Fusion-fission hybrid reactor, Nuclear Energy and Engineering, Neutron flux, Breeding blanket, RFP, 0103 physical sciences, Hybrid reactor, General Materials Science, Neutron, 010306 general physics, Joule heating, Civil and Structural Engineering
Abstract

The Reversed Field Pinch (RFP) configuration looks to be an attractive option for fusion-fission hybrid reactors: the toroidal magnetic systems would be made of copper coils instead of more expensive superconductive magnets; fusion conditions could be reached by ohmic heating only, therefore additional heating systems would not be required; the fission blanket could be located in the most external part of the torus thus facilitating maintenance operations. The paper aims at assessing the potentialities, such as fuel fertilization and/or nuclear waste transmutation and electricity production of a hybrid reactor with a RFP fusion core (R = 6 m, a = 1) whose conceptual design and plasma performances are based on RFX-mod, the largest RFP experiment currently in operation. Fusion conditions can be reached by heating a D-T plasma up to 9.6 keV by ohmic heating, generated by a 20 MA plasma current induced and sustained by flux swing only. The neutron flux (2.1 × 1013 fast neutron/cm2/s) is used to breed tritium in both the inner and outer blanket sections and induce fission reactions in dedicated areas in the external blanket section where Pu + MA (60%)-Zr (40%) rods are located. Both neutronic and safety analyses corroborate the viability of a FFH reactor with a RFP core.

Published
2019

250. Active MHD control at high currents in RFX-mod

Author

Emilio Martines, Lorella Carraro, A. Pizzimenti, D. Terranova, Paolo Franz, M. Brombin, P. Zaccaria, Rita Lorenzini, V. Antoni, E. Spada, Mario Cavinato, Roberto Cavazzana, S. Cappello, G. Rostagni, F. Milani, Paolo Zanca, L. Apolloni, N. Vianello, Vanni Toigo, L. Zanotto, C. Taliercio, N. Pomaro, Gianluca Spizzo, Giuseppe Zollino, Giuseppe Chitarin, C. Taccon, Barbara Zaniol, Federica Bonomo, A. Murari, A. De Lorenzi, Alessandra Canton, Matteo Zuin, Fulvio Auriemma, L. Garzotti, S. Ortolani, R. Paccagnella, S. C. Guo, Anton Soppelsa, Maria Ester Puiatti, Lionello Marrelli, Tommaso Bolzonella, Gabriele Manduchi, F. Sattin, S. Martini, Alessandro Fassina, G. Malesani, Luca Grando, P. Innocente, Giuseppe Marchiori, P. Piovesan, C. Alessi, D. F. Escande, Roberto Pasqualotto, L. De Pasqual, D. Bonfiglio, M. Valisa, Enrico Zilli, A. Cravotta, Paolo Bettini, A. Masiello, Matteo Agostini, R. Piovan, Diego Marcuzzi, G. Gadani, Piergiorgio Sonato, Alberto Alfier, L. Novello, Simone Peruzzo, Elena Gaio, S. Dal Bello, M. Spolaore, Piero Martin, E. Gazza, Francesco Gnesotto, Adriano Luchetta, Leonardo Giudicotti, P. Scarin, A. Buffa, Marco Gobbin, M. Moresco, G. Serianni, Martini, S, Agostini, M, Alessi, C, Alfier, A, Antoni, V, Apolloni, L, Auriemma, F, Bettini, P, Bolzonella, T, Bonfiglio, D, Bonomo, F, Brombin, M, Buffa, A, Canton, A, Cappello, S, Carraro, L, Cavazzana, R, Cavinato, M, Chitarin, G, Cravotta, A, Dal Bello, S, De Lorenzi, A, De Pasqual, L, Escande, D, Fassina, A, Franz, P, Gadani, G, Gaio, E, Garzotti, L, Gazza, E, Giudicotti, L, Gnesotto, F, Gobbin, M, Grando, L, Guo, S, Innocente, P, Lorenzini, R, Luchetta, A, Malesani, G, Manduchi, G, Marchiori, G, Marcuzzi, D, Marrelli, L, Martin, P, Martines, E, Masiello, A, Milani, F, Moresco, M, Murari, A, Novello, L, Ortolani, S, Paccagnella, R, Pasqualotto, R, Peruzzo, S, Piovan, R, Piovesan, P, Pizzimenti, A, Pomaro, N, Puiatti, M, Rostagni, G, Sattin, F, Scarin, P, Serianni, G, Sonato, P, Spada, E, Soppelsa, A, Spizzo, G, Spolaore, M, Taccon, C, Taliercio, C, Terranova, D, Toigo, V, Valisa, M, Vianello, N, Zaccaria, P, Zanca, P, Zaniol, B, Zanotto, L, Zilli, E, Zollino, G, and Zuin, M

Subjects
Physics, Nuclear and High Energy Physics, RFX-mod, Toroid, business.industry, Pulse duration, reversed field pinch, Plasma, Mechanics, Condensed Matter Physics, MHD control, Amplitude, Optics, Physics::Plasma Physics, RFP, Pinch, Magnetohydrodynamics, business, Voltage, Dynamo
Abstract

The modified RFX is a very flexible device used for a variety of control schemes for MHD instabilities and for advanced reverse field pinch scenarios. Relative to the previous machine, RFX-mod has a thin Cu shell with vertical field penetration time τS, lowered from 450 to 50 ms and shell/plasma proximity from b/a ≤ 1.24-1.1. Toroidal equilibrium is feedback-controlled and new power supplies provide better Bφ control. Newly designed graphite tiles protect the vessel from localized power deposition. A mesh of 192 external saddle coils, supervised by a digital feedback system, controls radial fields due to field errors and MHD modes. The paper presents an overview of the very encouraging results obtained using both new and 'standard' advanced operational modes in the current range 0.3-1 MA. A dramatic improvement of plasma performance was obtained by using the saddle coils to cancel all the radial field components, an operation mode dubbed virtual shell (VS). The toroidal voltage was lowered by more than 25% and the pulse length was tripled, up to 7 times the τS. Steady-state RFP pulses are now limited only by the applied volt-seconds. The improved magnetic boundary also has an effect on the tearing modes underlying the sustainment of the RFP, whose core amplitude is more than halved. The VS combined with new schemes for the active rotation of the MHD dynamo modes has allowed us to obtain reliable and well-controlled long RFP pulses in the MA current range. This results in a 100% increase in the particle and energy confinement time relative to the previous experiment and opens the possibility of exploring the machine performance in the 2 MA design range. © 2007 IAEA.

Published
2007

Catalog

Books, media, physical & digital resources
See catalog results