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An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameters only. In the plasma center, theoretical predictions on plasma current redistribution by a dynamo effect were confirmed experimentally. For core transport, the stabilizing effect of fast ion distributions on turbulent transport is shown to be important to explain the core isotope effect and improves the description of hollow low-Z impurity profiles. The L–H power threshold of hydrogen plasmas is not affected by small helium admixtures and it increases continuously from the deuterium to the hydrogen level when the hydrogen concentration is raised from 0 to 100%. One focus of recent campaigns was the search for a fusion relevant integrated plasma scenario without large edge localised modes (ELMs). Results from six different ELM-free confinement regimes are compared with respect to reactor relevance: ELM suppression by magnetic perturbation coils could be attributed to toroidally asymmetric turbulent fluctuations in the vicinity of the separatrix. Stable improved confinement mode plasma phases with a detached inner divertor were obtained using a feedback control of the plasma β. The enhanced Dα H-mode regime was extended to higher heating power by feedback controlled radiative cooling with argon. The quasi-coherent exhaust regime was developed into an integrated scenario at high heating power and energy confinement, with a detached divertor and without large ELMs. Small ELMs close to the separatrix lead to peeling-ballooning stability and quasi continuous power exhaust. Helium beam density fluctuation measurements confirm that transport close to the separatrix is important to achieve the different ELM-free regimes. Based on separatrix plasma parameters and interchange-drift-Alfvén turbulence, an analytic model was derived that reproduces the experimentally found important operational boundaries of the density limit and between L- and H-mode confinement. Feedback control for the X-point radiator (XPR) position was established as an important element for divertor detachment control. Stable and detached ELM-free phases with H-mode confinement quality were obtained when the XPR was moved 10 cm above the X-point. Investigations of the plasma in the future flexible snow-flake divertor of AUG by means of first SOLPS-ITER simulations with drifts activated predict beneficial detachment properties and the activation of an additional strike point by the drifts. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Peer Reviewed "Article signat per més de 50 autors/es: U. Stroth, D. Aguiam, E. Alessi, C. Angioni, N. Arden, R. Arredondo Parra, V. Artigues, O. Asunta, M. Balden, V. Bandaru, A. Banon-Navarro, K. Behler, A. Bergmann, M. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bielajew, R. Bilato, G. Birkenmeier, T. Blanken, V. Bobkov, A. Bock, T. Body, T. Bolzonella, N. Bonanomi, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, M. Brenzke, S. Brezinsek, D. Brida, F. Brochard, C. Bruhn, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, B. Cannas, P. Cano Megias, D. Carlton, M. Carr, P. Carvalho, C. Castaldo, M. Cavedon, C. Cazzaniga, C. Challis, A. Chankin, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G. Conway, S. Costea, D. Coster, T. Cote, A.J. Creely, G. Croci, D.J. Cruz Zabala, G. Cseh, A. Czarnecka, I. Cziegler, O. D'Arcangelo, A. Dal Molin, P. David, C. Day, M. de Baar, P. de Marné, R. Delogu, S. Denk, P. Denner, A. Di Siena, J.J. Dominguez Palacios Durán, D. Dunai, A. Drenik, M. Dreval, R. Drube, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, A. Encheva, K. Engelhardt, B. Erdös, I. Erofeev, B. Esposito, E. Fable, M. Faitsch, U. Fantz, M. Farnik, H. Faugel, F. Felici, O. Ficker, S. Fietz, A. Figueredo, R. Fischer, O. Ford, L. Frassinetti, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, S. Futatani, K. Galazka, J. Galdon-Quiroga, D. Gallart Escolà, A. Gallo10, Y. Gao11, S. Garavaglia3, M. Garcia Muñoz16, B. Geiger21, L. Giannone1, S. Gibson32, L. Gil2, E. Giovannozzi18, S. Glöggler1, M. Gobbin8, J. Gonzalez Martin, T. Goodman, G. Gorini, T. Görler, D. Gradic, G. Granucci, A. Gräter, H. Greuner, M. Griener, M. Groth, A. Gude, L. Guimarais, S. Günter, G. Haas, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, B. Heinemann, T. Hellsten, S. Henderson, P. Hennequin, A. Herrmann, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, J.H. Holm, M. Hölzl, C. Hopf, L. Horvath, T. Höschen, A. Houben, A. Hubbard, A. Huber, K. Hunger, V. Igochine, M. Iliasova, T. Ilkei, K. Insulander Björk, C. Ionita-Schrittwieser, I. Ivanova-Stanik, W. Jacob, N. Jaksic, F. Janky, A. Jansen van Vuuren, A. Jardin, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, A. Kallenbach, S. Kálvin, M. Kantor, A. Kappatou, O. Kardaun, J. Karhunen4, C.-P. Käsemann, S. Kasilov, A. Kendl, W. Kernbichler, E. Khilkevitch, A. Kirk, S. Kjer Hansen, V. Klevarova, G. Kocsis, M. Koleva, M. Komm, M. Kong, A. Krämer-Flecken, K. Krieger, A. Krivska, O. Kudlacek, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, A. Lahtinen, P.T. Lang, P. Lauber, N. Leuthold, L. Li, J. Likonen, O. Linder, B. Lipschultz, Y. Liu, A. Lohs, Z. Lu, T. Luda di Cortemiglia, N.C. Luhmann, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, A. Magnanimo, H. Maier, J. Mailloux, R. Maingi, O. Maj, E. Maljaars, P. Manas, A. Mancini, A. Manhard, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Marchetto, L. Marrelli, P. Martin, A. Martitsch, F. Matos, M. Mayer, M.-L. Mayoral, D. Mazon, P.J. McCarthy, R. McDermott, R. Merkel, A. Merle, D. Meshcheriakov, H. Meyer, D. Milanesio, P. Molina Cabrera, F. Monaco, M. Muraca, F. Nabais, V. Naulin, R. Nazikian, R.D. Nem, A. Nemes-Czopf, G. Neu, R. Neu, A.H. Nielsen, S.K. Nielsen, T. Nishizawa, M. Nocente, J.-M. Noterdaeme, I. Novikau, S. Nowak, M. Oberkofler, R. Ochoukov, J. Olsen, F. Orain, F. Palermo, O. Pan, G. Papp, I. Paradela Perez, A. Pau, G. Pautasso, C. Paz-Soldan, P. Petersson, P. Piovesan, C. Piron, U. Plank, B. Plaum, B. Plöck, V. Plyusnin, G. Pokol, E. Poli, L. Porte, T. Pütterich, M. Ramisch, J. Rasmussen, G. Ratta, S. Ratynskaia, G. Raupp, D. Réfy, M. Reich1, F. Reimold, D. Reiser, M. Reisner, D. Reiter, T. Ribeiro, R. Riedl, J. Riesch, D. Rittich, J.F. Rivero Rodriguez, G. Rocchi, P. Rodriguez-Fernandez, M. Rodriguez-Ramos, V. Rohde, G. Ronchi, A. Ross, M. Rott, M. Rubel, D.A. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, O. Samoylov, L. Sanchis Sanchez, J. Santos, O. Sauter, G. Schall, K. Schlüter, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, C. Schuster, T. Schwarz-Selinger, J. Schweinzer, E. Seliunin, A. Shabbir, A. Shalpegin, S. Sharapov, U. Sheikh, A. Shevelev, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, J. Simpson, S. Sipilä, E. Smigelskis, A. Snicker, E. Solano, C. Sommariva, C. Sozzi, G. Spizzo, M. Spolaore, A. Stegmeir, M. Stejner, J. Stober, E. Strumberge1, G. Suarez Lopez, H.-J. Sun, W. Suttrop, E. Sytova, T. Szepesi, B. Tál, T. Tala, G. Tardini, M. Tardocchi, D. Terranova, M. Teschke, E. Thorén, W. Tierens, D. Told, W. Treutterer, G. Trevisan, E. Trier, M. Tripský, M. Usoltceva, M. Valisa, M. Valovic, M. van Zeeland, F. Vannini, B. Vanovac, P. Varela, S. Varoutis, N. Vianello, J. Vicente, G. Verdoolaege, T. Vierle, E. Viezzer, I. Voitsekhovitch, U. von Toussaint, D. Wagner, X. Wang, M. Weiland, A.E. White, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, Q. Yang, Q. Yu, R. Zagórski, I. Zammuto, T. Zehetbauer, W. Zhang, W. Zholobenko, M. Zilker, A. Zito, H. Zohm, S. Zoletnik and the EUROfusion MST1 Team "

The Divertor Tokamak Test (DTT) facility [1], whose construction is starting in Frascati, will require robust and reliable diagnostics for the correct operation of the machine and the characterization of the plasma discharge. For this purpose, we are studying a common-path dispersion interferometer/polarimeter for the detection of plasma electron density and magnetic field in two different tangential chords in the equatorial plane. The physical principle is based on the generation of a second harmonic which crosses the plasma collinearly with the beam at its fundamental. Being the plasma a dispersive medium, the two beams are subject to different phase shifts from which it is possible to retrieve the plasma free electron density. Moreover, the unconverted part of the fundamental can be used for polarimetric measurement. Two different implementations of the interferometer have been considered, one with a CO2 laser (λ = 10.6/5.3 µm) and another one with Nd:YAG (λ = 1.064/0.536 µm). The former is more sensitive to lower plasma densities and to Faraday rotation, while the latter is more robust to fringe jumps. We have studied the main aspects of these two possible solutions. In particular, we analysed the optics to be used and the expected maximum signals for the interferometry and the polarimetry in a possible plasma scenario of DTT. A tentative draft of the layout of the optics inside the machine will be also presented.

A multi-channels poloidal interferometer/polarimeter is under development for the Divertor Tokamak Test (DTT) facility, a new tokamak device whose construction is starting in Italy. The aim of the diagnostics is the simultaneous measurement of the line integrated electron density, Faraday rotation and Cotton Mouton effect. The measurement of two polarimetric signals together with the interferometric one would allow for a robust electron density estimate, for the internal magnetic field measurement as well as for the magnetic equilibrium reconstruction. In this work, we present the advances in the diagnostics design whose characteristics are constrained by scientific requirements as well as the DTT structural aspects. In this regards, we have analyzed the possibility of accommodating up to 16 lines of sight in the available space and the contribution of different chords positions in the magnetic equilibrium reconstruction. In particular, we have used the VMEC and V3FIT codes to evaluate the expected interferometric/polarimetric signals and their contribution in the reconstruction of the q profile. These results have been used to optimize the chords positions. Eventually, we present a realistic CAD-driven design of the diagnostic, with details of the most critical components (e.g. the corner cube retroreflectors in the high field side), which would allow for the selected chords configurations implementation.

Since the 2018 IAEA FEC Conference, FTU operations have been devoted to several experiments covering a large range of topics, from the investigation of the behaviour of a liquid tin limiter to the runaway electrons mitigation and control and to the stabilization of tearing modes by electron cyclotron heating and by pellet injection. Other experiments have involved the spectroscopy of heavy metal ions, the electron density peaking in helium doped plasmas, the electron cyclotron assisted start-up and the electron temperature measurements in high temperature plasmas. The effectiveness of the laser induced breakdown spectroscopy system has been demonstrated and the new capabilities of the runaway electron imaging spectrometry system for in-flight runaways studies have been explored. Finally, a high resolution saddle coil array for MHD analysis and UV and SXR diamond detectors have been successfully tested on different plasma scenarios.

The diagnostic performances of photodetectors based on Chemical Vapor Deposition (CVD) single crystal diamonds that were installed on one of the equatorial ports of the FTU tokamak during the last six months of operation of the machine are reported. Examples of plasma fast events have been collected in several different plasma conditions, confirming the fast response capabilities of diamond detectors and the high S/N ratio. During the Runaway Control and Mitigation experiments, for example, the so-called Anomalous Doppler Instabilities were observed as sharp peaks of Ly-α emission caused by fast electrons hitting the wall, as a result of RE beam instabilities, perfectly correlated in time with other magnetic diagnostics and fast EC polychromator signals. Fast oscillations in the plasma emission are also observed in the presence of tearing modes, while other interesting observations relate to pellet ablation processes. The CVD diamond detectors were installed on FTU in view of their possible use for replacement of the Si photodiodes currently adopted for Soft X-Ray tomography (SXT) on future devices with harsher radiation environments. In fact, it was realized that the relatively flat response of the UV diamond sensor opened the possibility of using these detectors as bolometers. The first encouraging results have prompted launching an R&D program for the development of full-fledged diamond bolometers, which will be especially well suited for the coverage of the divertor and edge regions in high performance devices, in the energy range from 10 eV to about 20 keV.

The new multichannel X-mode reflectometer installed on ASDEX Upgrade measures the plasma density profile evolution at different positions in front of the ICRF antenna. The reflectometer operates in the extended U-band (40–68 GHz) microwave region, measuring density profiles up to 2 × 1019 m−3 with magnetic fields between 1.5 T and 2.7 T. In this heterodyne reflectometer architecture, the signal reflected by the plasma is down-shifted and quadrature detectors demodulate its in-phase and quadrature (IQ) components. In this work we analysed the acquired IQ signals from the different reflectometer antennas, and describe the waveguide dispersion calibration and filtering of the raw signal. The effect of spurious reflections, such as the multiple reflections from the ICRF antenna metal straps, are analysed and taken into account on the data processing software. In high plasma density and high magnetic field scenarios, both the lower and upper X-mode cut off frequencies are detected in the probing range. The first fringe (FF) reflection of the upper cut off indicates the start of the plasma signal and must be determined robustly to reduce density profile errors. Existing FF estimation algorithms based on signal amplitude and spectral information may still fail in the presence of both upper and lower cut off reflections.

Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened. Peer Reviewed Article escrit per 365 autors/autores: Labit, B.; Eich, T.; Harrer, G. F.; Wolfrum, E.; Bernert, M.; Dunne, M. G.; Frassinetti, L.; Hennequin, P.; Maurizio, R.; Merle, A.; Meyer, H.; Saarelma, S.; Sheikh, U.; Adamek, J.; Agostini, M.; Aguiam, D.; Akers, R.; Albanese, R.; Albert, C.; Alessi, E.; Ambrosino, R.; Andr be, Y.; Angioni, C.; Apruzzese, G.; Aradi, M.; Arnichand, H.; Auriemma, F.; Avdeeva, G.; Ayllon-Guerola, J. M.; Bagnato, F.; Bandaru, V. K.; Barnes, M.; Barrera-Orte, L.; Bettini, P.; Bilato, R.; Biletskyi, O.; Bilkova, P.; Bin, W.; Blanchard, P.; Blanken, T.; Bobkov, V.; Bock, A.; Boeyaert, D.; Bogar, K.; Bogar, O.; Bohm, P.; Bolzonella, T.; Bombarda, F.; Boncagni, L.; Bouquey, F.; Bowman, C.; Brezinsek, S.; Brida, D.; Brunetti, D.; Bucalossi, J.; Buchanan, J.; Buermans, J.; Bufferand, H.; Buller, S.; Buratti, P.; Burckhart, A.; Calabr, G.; Calacci, L.; Camenen, Y.; Cannas, B.; Cano Megías, P.; Carnevale, D.; Carpanese, F.; Carr, M.; Carralero, D.; Carraro, L.; Casolari, A.; Cathey, A.; Causa, F.; Cavedon, M.; Cecconello, M.; Ceccuzzi, S.; Cerovsky, J.; Chapman, S.; Chmielewski, P.; Choi, D.; Cianfarani, C.; Ciraolo, G.; Coda, S.; Coelho, R.; Colas, L.; Colette, D.; Cordaro, L.; Cordella, F.; Costea, S.; Coster, D.; Cruz Zabala, D. J.; Cseh, G.; Czarnecka, A.; Cziegler, I.; D’Arcangelo, O.; Dal Molin, A.; David, P.; De Carolis, G.; De Oliveira, H.; Decker, J.; Dejarnac, R.; Delogu, R.; Den Harder, N.; Dimitrova, M.; Dolizy, F.; Domínguez-Palacios Durán, J. J.; Douai, D.; Drenik, A.; Dreval, M.; Dudson, B.; Dunai, D.; Duval, B. P.; Dux, R.; Elmore, S.; Embréus, O.; Erds, B.; Fable, E.; Faitsch, M.; Fanni, A.; Farnik, M.; Faust, I.; Faustin, J.; Fedorczak, N.; Felici, F.; Feng, S.; Feng, X.; Ferreira, J.; Ferr, G.; Février, O.; Ficker, O.; Figini, L.; Figueiredo, A.; Fil, A.; Fontana, M.; Francesco, M.; Fuchs, C.; Futatani, S.; Gabellieri, L.; Gadariya, D.; Gahle, D.; Galassi, D.; Gałązka, K.; Galdon-Quiroga, J.; Galeani, S.; Gallart, D.; Gallo, A.; Galperti, C.; Garavaglia, S.; Garcia, J.; Garcia-Lopez, J.; Garcia-Mu oz, M.; Garzotti, L.; Gath, J.; Geiger, B.; Giacomelli, L.; Giannone, L.; Gibson, S.; Gil, L.; Giovannozzi, E.; Giruzzi, G.; Gobbin, M.; Gonzalez-Martin, J.; Goodman, T. P.; Gorini, G.; Gospodarczyk, M.; Granucci, G.; Grekov, D. 1; Grenfell, G.; Griener, M.; Groth, M.; Grover, O.; Gruca, M.; Gude, A.; Guimarais, L.; Gyergyek, T.; Hacek, P.; Hakola, A.; Ham, C.; Happel, T.; Harrison, J.; Havranek, A.; Hawke, J.; Henderson, S.; Hesslow, L.; Hitzler, F.; Hnat, B.; Hobirk, J.; Hoelzl, M.; Hogeweij, D.; Hopf, C.; Hoppe, M.; Horacek, J.; Hron, M.; Huang, Z.; Iantchenko, A.; Iglesias, D.; Igochine, V.; Innocente, P.; Ionita-Schrittwieser, C.; Isliker, H.; Ivanova-Stanik, I.; Jacobsen, A.; Jakubowski, M.; Janky, F.; Jardin, A.; Jaulmes, F.; Jensen, T.; Jonsson, T.; Kallenbach, A.; Kappatou, A.; Karpushov, A.; Kasilov, S.; Kazakov, Y.; Kazantzidis, P. V.; Keeling, D.; Kelemen, M.; Kendl, A.; Kernbichler, W.; Kirk, A.; Kocsis, G.; Komm, M.; Kong, M.; Korovin, V.; Koubiti, M.; Kovacic, J.; Krawczyk, N.; Krieger, K.; Kripner, L.; Křivská, A.; Kudlacek, O.; Kulyk, Y.; Kurki-Suonio, T.; Kwiatkowski, R.; Laggner, F.; Laguardia, L.; Lahtinen, A.; Lang, P.; Likonen, J.; Lipschultz, B.; Liu, F.; Lombroni, R.; Lorenzini, R.; Loschiavo, V. P.; Lunt, T.; MacUsova, E.; Madsen, J.; Maggiora, R.; Maljaars, B.; Manas, P.; Mantica, P.; Mantsinen, M. J.; Manz, P.; Maraschek, M.; Marchenko, V.; Marchetto, C.; Mariani, A.; Marini, C.; Markovic, T.; Marrelli, L.; Martin, P.; Martín Solís, J. R.; Martitsch, A.; Mastrostefano, S.; Matos, F.; Matthews, G.; Mayoral, M.-L.; Mazon, D.; Mazzotta, C.; Mc Carthy, P.; McClements, K.; McDermott, R.; McMillan, B.; Meineri, C.; Menkovski, V.; Meshcheriakov, D.; Messmer, M.; Micheletti, D.; Milanesio, D.; Militello, F.; Miron, I. G.; Mlynar, J.; Moiseenko, V.; Molina Cabrera, P. A.; Morales, J.; Moret, J.-M.; Moro, A.; Moulton, D.; Nabais, F.; Naulin, V.; Naydenkova, D.; Nem, R. D.; Nespoli, F.; Newton, S.; Nielsen, A. H.; Nielsen, S. K.; Nikolaeva, V.; Nocente, M.; Nowak, S.; Oberkofler, M.; Ochoukov, R.; Ollus, P.; Olsen, J.; Omotani, J.; Ongena, J.; Orain, F.; Orsitto, F. P.; Paccagnella, R.; Palha, A.; Panaccione, L.; Panek, R.; Panjan, M.; Papp, G.; Paradela Perez, I.; Parra, F.; Passeri, M.; Pau, A.; Pautasso, G.; Pavlichenko, R.; Perek, A.; Pericoli Radolfini, V.; Pesamosca, F.; Peterka, M.; Petrzilka, V.; Piergotti, V.; Pigatto, L.; Piovesan, P.; Piron, C.; Piron, L.; Plyusnin, V.; Pokol, G.; Poli, E.; Pölöskei, P.; Popov, T.; Popovic, Z.; Pór, G.; Porte, L.; Pucella, G.; Puiatti, M. E.; Pütterich, T.; Rabinski, M.; Juul Rasmussen, J.; Rasmussen, J.; Rattá, G. A.; Ratynskaia, S.; Ravensbergen, T.; Réfy, D.; Reich, M.; Reimerdes, H.; Reimold, F.; Reiser, D.; Reux, C.; Reznik, S.; Ricci, D.; Rispoli, N.; Rivero-Rodriguez, J. F.; Rocchi, G.; Rodriguez-Ramos, M.; Romano, A.; Rosato, J.; Rubinacci, G.; Rubino, G.; Ryan, D. A.; Salewski, M.; Salmi, A.; Samaddar, D.; Sanchis-Sanchez, L.; Santos, J.; Särkimäki, K.; Sassano, M.; Sauter, O.; Scannell, R.; Scheffer, M.; Schneider, B. S.; Schneider, P.; Schrittwieser, R.; Schubert, M.; Seidl, J.; Seliunin, E.; Sharapov, S.; Sheeba, R. R.; Sias, G.; Sieglin, B.; Silva, C.; Sipilä, S.; Smith, S.; Snicker, A.; Solano, E. R.; Hansen, S. K.; Soria-Hoyo, C.; Sorokovoy, E.; Sozzi, C.; Sperduti, A.; Spizzo, G.; Spolaore, M.; Stejner, M.; Stipani, L.; Stober, J.; Strand, P.; Sun, H.; Suttrop, W.; Sytnykov, D.; Szepesi, T.; Tál, B.; Tala, T.; Tardini, G.; Tardocchi, M.; Teplukhina, A.; Terranova, D.; Testa, D.; Theiler, C.; Thorén, E.; Thornton, A.; Tilia, B.; Tolias, P.; Tomes, M.; Toscano-Jimenez, M.; Tsironis, C.; Tsui, C.; Tudisco, O.; Urban, J.; Valisa, M.; Vallar, M.; Vallejos Olivares, P.; Valovic, M.; Van Vugt, D.; Vanovac, B.; Varje, J.; Varju, J.; Varoutis, S. 1; Vartanian, S.; Vasilovici, O.; Vega, J.; Verdoolaege, G.; Verhaegh, K.; Vermare, L.; Vianello, N.; Vicente, J.; Viezzer, E.; Villone, F.; Voitsekhovitch, I.; Voltolina, D.; Vondracek, P.; Vu, N. M. T.; Walkden, N.; Wauters, T.; Weiland, M.; Weinzettl, V.; Wensing, M.; Wiesen, S.; Wiesenberger, M.; Wilkie, G.; Willensdorfer, M.; Wischmeier, M.; Wu, K.; Xiang, L.; Zagorski, R.; Zaloga, D.; Zanca, P.; Zaplotnik, R.; Zebrowski, J.; Zhang, W.; Zisis, A.; Zoletnik, S.; Zuin, M.

PROTO-SPHERA (Spherical Plasma for Helicity Relaxation Assessment) is a new concept of torus that aims to produce a spherical torus with closed flux surfaces and a force-free Screw Pinch with open flux surfaces, fed by electrodes. In order to verify the stability of the configuration and the technical components of the PROTO-SPHERA initial arc, the initial Phase-1 experiment was built, and its plasma, in the year 2108, has reached both the total current (10 kA) and total duration (1 s) targets. A two colour interferometer is one of the diagnostic system proposed to provide PROTO-SPHERA with the measurement of its electron density, which is currently of the order of ∼1020 m−3. It will allow to obtain line density, necessary to characterize this uncommon plasma, as integrate measurement along the equatorial plane. The design and the interferometer characteristics are described in this paper.

The evidence of Parametric Decay Instabilities (PDI) excited by the ECH power injected in O-Mode has been explored in FTU Tokamak, using the Collective Thomson Scattering (CTS) diagnostic. The experiments show evidences to support the hypothesis of low-threshold excitation of waves generated by PDI mechanisms, formerly proposed in the case of 2nd harmonic X-mode injection in TEXTOR and ASDEX-U. Theoretical analysis predicts low-threshold parametric decay also for O-mode pump-wave injection, which can be injected in FTU at frequencies close to the first Harmonic EC resonance. Experiments were made at different magnetic fields, injecting the 140 GHz probe and observing the emission from the second antenna of the EC launcher in poloidally symmetric and asymmetric configurations, in presence of MHD islands. The signal is detected by the CTS radiometers, with a fast digitizer allowing the spectral reconstruction at very fine time and frequency scales. Different types of emissions are studied in detail, comparing them with the magnetic island rotation frequency in different plasma conditions. In order to locate the plasma volume originating the emissions, a new antenna and receiving line has been installed.

Measurements of total radiated power are very important in tokamak plasmas, especially in the divertor region where they are required for heat flux active control. Bolometric detectors based on metal foils are used as sensors. The signal readout is provided by an electronic system which drives processes and acquires the signals from the resistive bridge-based bolometer. A project for a new electronic system is being carried on at ENEA Frascati Laboratories, aimed to develop an architecture and a system sufficiently flexible in order to be applied to large fusion devices, such as DTT and ITER. The project, conceived for high reliability and lasting time levels, is based on FPGA boards and a completely digital lock-in. A prototype has been recently tested both in the laboratory and on FTU plasma. A key point of the project is the capability of on-line calibration. The paper describes the architecture of the project for the bolometric diagnostic and the analysis of the first results on FTU plasma.

A new receiving antenna for collecting signals of the Collective Thomson Scattering (CTS) diagnostics in FTU Tokamak has been recently installed. The squared corrugated section and the precisely defined length make it possible to receive from different directions by remotely steering the receiving mirrors. This type of Remote-Steering (RS) antennas, being studied on FTU for the DEMO Electron Cyclotron Heating (ECH) system launch, is already installed on the W7- X stellarator and will be tested in the next campaign. The transmission of the signal from the antenna in the tokamak hall to the CTS diagnostics hall will be mainly realized by means of oversized circular corrugated waveguides carrying the hybrid HE11 (quasi-gaussian) waveguide mode, with inclusion of a special smooth-waveguide section and a short run of reduced-size square-corrugated waveguide through the tokamak bio-shield. The coupling between different waveguide types is made with ellipsoidal focusing mirrors, using quasi-optical matching formulas between the gaussian-shaped beams in input and output to the waveguides. In this work, after a complete study of feasibility of the overall line, a design for the receiving line will be proposed, in order to realize an executive layout to be used as a guideline for the commissioning phase. © 2018 ENEA. Published by IOP Publishing Ltd on behalf of Sissa Medialab.

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The ASDEX Upgrade (AUG) programme, jointly run with the EUROfusion MST1 task force, continues to significantly enhance the physics base of ITER and DEMO. Here, the full tungsten wall is a key asset for extrapolating to future devices. The high overall heating power, flexible heating mix and comprehensive diagnostic set allows studies ranging from mimicking the scrape-off-layer and divertor conditions of ITER and DEMO at high density to fully non-inductive operation (q95 = 5.5, ) at low density. Higher installed electron cyclotron resonance heating power 6 MW, new diagnostics and improved analysis techniques have further enhanced the capabilities of AUG. Stable high-density H-modes with MW m−1 with fully detached strike-points have been demonstrated. The ballooning instability close to the separatrix has been identified as a potential cause leading to the H-mode density limit and is also found to play an important role for the access to small edge-localized modes (ELMs). Density limit disruptions have been successfully avoided using a path-oriented approach to disruption handling and progress has been made in understanding the dissipation and avoidance of runaway electron beams. ELM suppression with resonant magnetic perturbations is now routinely achieved reaching transiently . This gives new insight into the field penetration physics, in particular with respect to plasma flows. Modelling agrees well with plasma response measurements and a helically localised ballooning structure observed prior to the ELM is evidence for the changed edge stability due to the magnetic perturbations. The impact of 3D perturbations on heat load patterns and fast-ion losses have been further elaborated. Progress has also been made in understanding the ELM cycle itself. Here, new fast measurements of and Er allow for inter ELM transport analysis confirming that Er is dominated by the diamagnetic term even for fast timescales. New analysis techniques allow detailed comparison of the ELM crash and are in good agreement with nonlinear MHD modelling. The observation of accelerated ions during the ELM crash can be seen as evidence for the reconnection during the ELM. As type-I ELMs (even mitigated) are likely not a viable operational regime in DEMO studies of 'natural' no ELM regimes have been extended. Stable I-modes up to have been characterised using -feedback. Core physics has been advanced by more detailed characterisation of the turbulence with new measurements such as the eddy tilt angle—measured for the first time—or the cross-phase angle of and fluctuations. These new data put strong constraints on gyro-kinetic turbulence modelling. In addition, carefully executed studies in different main species (H, D and He) and with different heating mixes highlight the importance of the collisional energy exchange for interpreting energy confinement. A new regime with a hollow profile now gives access to regimes mimicking aspects of burning plasma conditions and lead to nonlinear interactions of energetic particle modes despite the sub-Alfvénic beam energy. This will help to validate the fast-ion codes for predicting ITER and DEMO. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under grant agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. "Article signat per més de 100 autors/es: H. Meyer, for the AUG Team: D. Aguiam, C. Angioni, C.G. Albert, N. Arden, R. Arredondo Parra, O. Asunta, M. de Baar, M. Balden, V. Bandaru, K. Behler, A. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bilato, G. Birkenmeier, T.C. Blanken, V. Bobkov, A. Bock, T. Bolzonella, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, S. Brezinsek, D. Brida, F. Brochard, C. Bruhn, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, D. Carlton, M. Carr, D. Carralero, C. Castaldo, M. Cavedon, C. Cazzaniga, S. Ceccuzzi, C. Challis, A. Chankin, S. Chapman, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G.D. Conway, S. Costea, D.P. Coster, T.B. Cote, A. Creely, G. Croci, G. Cseh, A. Czarnecka, I. Cziegler, O. D'Arcangelo, P. David, C. Day, R. Delogu, P. de Marné, S.S. Denk, P. Denner, M. Dibon, A. Di Siena, D. Douai, A. Drenik, R. Drube, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, K. Engelhardt, B. Erdös, I. Erofeev, B. Esposito, E. Fable, M. Faitsch, U. Fantz, H. Faugel, I. Faust, F. Felici, J. Ferreira, S. Fietz, A. Figuereido, R. Fischer, O. Ford, L. Frassinetti, S. Freethy, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, K. Galazka, J. Galdon-Quiroga, A. Gallo, Y. Gao, S. Garavaglia, A. Garcia-Carrasco, M. Garcia-Muñoz, B. Geiger, L. Giannone, L. Gil, E. Giovannozzi, C. Gleason-González, S. Glöggler, M. Gobbin, T. Görler, I. Gomez Ortiz, J. Gonzalez Martin, T. Goodman, G. Gorini, D. Gradic, A. Gräter, G. Granucci, H. Greuner, M. Griener, M. Groth, A. Gude, S. Günter, L. Guimarais, G. Haas, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G.F. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, C.C. Hegna, B. Heinemann, S. Heinzel, T. Hellsten, S. Henderson, P. Hennequin, A. Herrmann, M.F. Heyn, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, M. Hölzl, T. Höschen, J.H. Holm, C. Hopf, W.A. Hornsby, L. Horvath, A. Houben, A. Huber, V. Igochine, T. Ilkei, I. Ivanova-Stanik, W. Jacob, A.S. Jacobsen, F. Janky, A. Jansen van Vuuren, A. Jardin, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, C.-P. Käsemann, A. Kallenbach, S. Kálvin, M. Kantor, A. Kappatou, O. Kardaun, J. Karhunen, S. Kasilov,, Y. Kazakov, W. Kernbichler, A. Kirk, S. Kjer Hansen, V. Klevarova, G. Kocsis, A. Köhn, M. Koubiti, K. Krieger, A. Krivska, A. Krämer-Flecken, O. Kudlacek, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, P.T. Lang, P. Lauber, A. Lebschy, N. Leuthold, M. Li, O. Linder, B. Lipschultz, F. Liu, Y. Liu, A. Lohs, Z. Lu, T. Luda di Cortemiglia, N.C. Luhmann, R. Lunsford, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, R. Maggiora, H. Maier, O. Maj, J. Mailloux, R. Maingi, E. Maljaars, P. Manas, A. Mancini, A. Manhard, M.-E. Manso, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Martens, P. Martin, L. Marrelli, A. Martitsch, M. Mayer, D. Mazon, P.J. McCarthy, R. McDermott, H. Meister, A. Medvedeva, R. Merkel, A. Merle, V. Mertens, D. Meshcheriakov, O. Meyer, J. Miettunen, D. Milanesio, F. Mink, A. Mlynek, F. Monaco, C. Moon, F. Nabais, A. Nemes-Czopf, G. Neu, R. Neu, A.H. Nielsen, S.K. Nielsen, V. Nikolaeva, M. Nocente, J.-M. Noterdaeme, I. Novikau, S. Nowak, M. Oberkofler, M. Oberparleiter, R. Ochoukov, T. Odstrcil, J. Olsen, F. Orain, F. Palermo, O. Pan, G. Papp, I. Paradela Perez, A. Pau, G. Pautasso, F. Penzel, P. Petersson, J. Pinzón Acosta, P. Piovesan, C. Piron, R. Pitts, U. Plank, B. Plaum, B. Ploeckl, V. Plyusnin, G. Pokol, E. Poli, L. Porte, S. Potzel, D. Prisiazhniuk, T. Pütterich, M. Ramisch, J. Rasmussen, G.A. Rattá, S. Ratynskaia, G. Raupp, G.L. Ravera, D. Réfy, M. Reich, F. Reimold, D. Reiser, T. Ribeiro, J. Riesch, R. Riedl, D. Rittich, J.F. Rivero-Rodriguez, G. Rocchi, M. Rodriguez-Ramos, V. Rohde, A. Ross1, M. Rott, M. Rubel, D. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, L. Sanchis-Sanchez, J. Santos, O. Sauter, A. Scarabosio, G. Schall, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, T. Schwarz-Selinger, J. Schweinzer, B. Scott, T. Semer, E. Seliunin, M. Sertoli, A. Shabbir, A. Shalpegin, L. Shao, S. Sharapov, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, P. Simon, J. Simpson, E. Smigelskis, A. Snicker, C. Sommariva, C. Sozzi, M. Spolaore, A. Stegmeir, M. Stejner, J. Stober, U. Stroth, E. Strumberger, G. Suarez, H.-J. Sun, W. Suttrop, E. Sytova, T. Szepesi, B. Tál, T. Tala, G. Tardini, M. Tardocchi, M. Teschke, D. Terranova, W. Tierens, E. Thorén, D. Told, P. Tolias, O. Tudisco, W. Treutterer, E. Trier, M. Tripský, M. Valisa, M. Valovic, B. Vanovac, D. van Vugt, S. Varoutis, G. Verdoolaege, N. Vianello, J. Vicente, T. Vierle, E. Viezzer, U. von Toussaint, D. Wagner, N. Wang, X. Wang, M. Weiland, A.E. White, S. Wiesen, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, L. Xiang, Q. Yang, Z. Yang, Q. Yu, R. Zagórski, I. Zammuto, W. Zhang, M. van Zeeland, T. Zehetbauer, M. Zilker, S. Zoletnik, H. Zohm and the EUROfusion MST1 Team55

Health cooperation with Balkan Countries in diagnosis and care of congenital heart malformations was developed since 2008 by the Heart Hospital of “Gabriele Monasterio” Tuscany Foundation (FTGM) jointly with the Association “Un Cuore un Mondo” and with the support of the Tuscany Region. A tele-echocardiography network was implemented interconnecting the Heart Hospital in Massa with selected Pediatric and Gynecology centers in Croatia, Bosnia-Herzegovina, Albania, and Romania. Up to 100 patients were transferred to Massa from Balkan countries for specialized care or cardiac surgery. This initiative was recently empowered in the frame of European IPA program by the AdriHealthMob project, aimed at providing cross border healthcare services in the Adriatic area, and since 2015 a telemedicine network for heart malformations has being developed (namely, “Arriviamo al Cuore di Tutti”) in Tuscany with the financial support of Lions Clubs and their International Foundation (LCIF), jointly with regional healthcare authorities.

Special issue featuring the invited talks from the 43rd EPS Conference on Plasma Physics, Leuven, 4-8 July, 2016 We present an overview of FTU experiments on runaway electron (RE) generation and control carried out through a comprehensive set of real-time (RT) diagnostics/control systems and newly installed RE diagnostics. An RE imaging spectrometer system detects visible and infrared synchrotron radiation. A Cherenkov probe measures RE escaping the plasma. A gamma camera provides hard x-ray radial profiles from RE bremsstrahlung interactions in the plasma. Experiments on the onset and suppression of RE show that the threshold electric field for RE generation is larger than that expected according to a purely collisional theory, but consistent with an increase due to synchrotron radiation losses. This might imply a lower density to be targeted with massive gas injection for RE suppression in ITER. Experiments on active control of disruption-generated RE have been performed through feedback on poloidal coils by implementing an RT boundary-reconstruction algorithm evaluated on magnetic moments. This work was carried out within the framework of the EUROfusion Consortium and received funding from the Euratom research and training programme 2014–2018 under grant agreement No 633053 (Projects MST2-9 and MST2-15). The views and opinions expressed herein do not necessarily reflect those of the European Commission. Additional financial support was received from MINECO (Spain), Projects No. ENE2012-31753 and ENE2015-66444-R. Publicado

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A new ECRH launcher mainly aimed at experiments on MHD stabilization has been recently installed in FTU and integrated with a Real Time controller. The new plug-in antenna is capable of injecting two beams over wide angular ranges, ±40 in toroidal and ±15 < θ < 44 in poloidal direction with fast mirror speed. The power is delivered to the launcher with two additional transmission lines (TL) connected to the existing ECRH system with remotely controlled switches. After the optical alignment of the TLs, a campaign of tests on the steering antenna was made with the launcher ex- and in-vessel. A procedure to calibrate the absolute mirror angular position was developed and successfully used. First high power pulses were carried out on plasma target delivering 2 × 0.3 MW EC power for 200 ms. © 2013 CNR-IFP Instituto di Fisica Plasma.

Plasma properties can be useful in a wide spectrum of applications. Experimental projects on controlled nuclear fusion are the most challenging of these applications and, at the same time, the best way to approach plasma science. Since nuclear fusion reactors can ensure a large-scale, safe, environmentally-friendly and virtually inexhaustible source of energy, several fusion-oriented megaprojects and innovative companies are appearing all over the world. PROTO-SPHERA (Spherical Plasma for HElicity Relaxation Assessment) is the first plasma project with a simply connected configuration, namely not requiring additional objects inside the plasma volume. This is obtained by a plasma arc, shaped as a screw pinch, acting as the centerpost of a spherical torus with minimal aspect ratio. Due to its intrinsic physical, engineering and economic advantages, this new approach is attractive also on an industrial scale and with several developments that still needs to be explored. This paper presents the PROTO-SPHERA basic principles, its first encouraging results and its expected and potential evolutions.

Runaway Electrons (REs) are beams of electrons within a tokamak plasma, accelerated to velocities close to the speed of light. They represent a major concern in tokamaks because they are lost to the first wall, resulting in significant local energy deposition, local melting and damage of plasma-facing components. Key to the successful operation of tokamaks, and in particular of ITER and future energy-generation reactors such a DEMO, is the ability to avoid and control REs to mitigate their impact on the machine operation. A comprehensive experimental program on the study of REs has been developed at FTU by the integration of diagnostic, hardware and software tools in real-time (RT) plasma control system, including the CO2 scanning interferometer for RE position control, a fission chamber to monitor RE interactions with plasma-facing components and the hard x-ray radial profile monitor for the measurement of in-plasma bremsstrahlung from REs. Further, two new diagnostics have been developed specifically to measure in-flight and lost REs, respectively, the RE Imaging Spectrometer system (REIS) and a Cherenkov probe. The REIS provides both image and (visible and infrared) spectra of RE synchrotron emission, providing information on the RE energy distribution function. The Cherenkov probe, installed within the plasma scrape-off layer, detects RE losses, enabling the study of RE dynamics in the presence of magnetic islands. This probe provided also first evidence of RE losses in the presence of beta induced Alfvén eigenmodes using a non-magnetic diagnostics. A three-channel Cherenkov probe is being installed, to permit energy discrimination and simultaneous data collection from different toroidal/poloidal positions. An analysis of the experimental data obtained in FTU

Characterization and calibration measurements of two Cherenkov probes have been performed in ENEA Frascati's laboratories. Different kinds of radiation have been used, from visible light to x-rays, in order to evaluate possible spurious responses of the probes. Moreover, a preliminary calibration is presented, as well as a first evaluation of the minimum single probe's detectable flux performed through an electron beam of 2.3 MeV. Additional results have been obtained thanks to spectrometry analysis, which gave deeper insights of the phenomena occurring inside the probes. In particular, a continuous emission spectrum, associated to cathodoluminescence, has been observed to dominate in the Cherenkov range, showing that scintillating phenomena are not negligible in this kind of probes. Results on non-thermal electron losses from recent FTU experimental campaigns are also presented. The signals acquired are compared to those from other diagnostics like x-rays, neutron and gamma detectors or plasma magnetic activity, showing good correlation between them. The analysis focuses on the capability and sensitivity of the probes to measure runaway electrons losses with energy discrimination in presence of perturbations due to kinetic and magnetic reconnection phenomena. © 2018 IOP Publishing Ltd.

OBJECTIVEDespite increased information on the importance of an inappropriate inflammatory response in the acute Charcot process, there has been no previous attempt to define the specific pathways that mediate its pathogenesis. Here, the role played by monocytes was analyzed.RESEARCH DESIGN AND METHODSThe immune phenotype of peripheral monocytes was studied by fluorescence-activated cell sorter analysis comparing patients with acute Charcot (n = 10) in both the active and recovered phase, diabetic patients with neuropathy (with or without osteomyelitis), and normal control subjects.RESULTSWhen compared with diabetic control subjects and healthy subjects, monocytes from acute Charcot patients showed a proinflammatory immune phenotype characterized by increased production of proinflammatory cytokines, reduced secretion of anti-inflammatory cytokines, increased expression of surface costimulatory molecules, and increased resistance to serum withdrawal-induced apoptosis. In addition, the pattern of circulating cytokines confirmed activation of proinflammatory cytokines. No modulation of the monocyte phenotype was documented in diabetic control subjects and healthy subjects, thus indicating that the proinflammatory alterations of monocytes are specific and causative of acute Charcot.CONCLUSIONSTogether, these data provide evidence for the role of proinflammatory changes in the immune phenotype of monocytes in the pathogenesis of acute Charcot. These alterations may explain the abnormally intense and prolonged inflammatory response that characterizes this disorder and may represent a potential therapeutic target for specific pharmacological interventions.

The behaviour of the Pleistocene Osaka clays at Kansai International Airport Phase 1 island is investigated by FEM analyses using an elasto-viscoplastic constitutive model which replicates the destruction processes occurring in the microstructure of the clay. Excellent predictions are obtained by 2D analyses carried out using the actual soil profile and the characteristic values of soil parameters, confirming the validity of the methods proposed for characterizing and modelling structured clays. Unlike 1D analyses, where partially effective drainage layers occur, 2D analyses do not require arbitrary pre-definition of the model drainage scenario and of the ‘equivalent’ permeability of interlayered clays to account for macrostructure. In these conditions, 1D analyses must be validated with reference to 2D or 3D prototype analyses and/or well documented experience of comparable work. Once thus validated, 1D analyses are used to investigate the relative merits of possible measures (relief wells, preloading, l...

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Enhanced settlement and pore pressure predictions in structured clays are shown to be possible by applying a framework specifically developed to identify metastable microstructure and to simulate with appropriate elastoviscoplastic models the associated destruction processes, which are responsible for large time-dependent strains (creep). Two well-documented case histories, Maishima island and Kansai International Airport Phase 1 island, are considered to support this conclusion. The ‘field’ behaviour of Osaka clays at these two sites demonstrates that ‘primary compression’ settlements predicted by elastoplastic models and conventional interpretation of oedometer tests may be substantially lower than observed, casting doubt on the uniqueness of the ‘end of primary’ (EOP) void ratio–effective stress relationship, which is found to provide reliable predictions only under special circumstances. The concepts of primary and secondary consolidation, and parameters such as the preconsolidation pressure , the com...

A scanning interferometer has been developed and installed on the FTU tokamak for plasma density profile measurements. A scanning system is equivalent to a multi-chord system while keeping the optical scheme as simple as a single-chord interferometer. This new diagnostic has achieved a spatial resolution of ~1 cm and a time resolution of 62 ?s. In this paper, we present the first measurements carried out with this interferometer showing its peculiar capabilities. Particular care has been paid to the analysis of pellet fuelled discharges, where the fast and large density change (1021 m-3 in 100 ?s) is a great challenge for the system. Results and problems with the inversion are reported. Comparison with other FTU diagnostics is also presented.

In FTU, density profile is measured with two new diagnostics: a CO2/CO scanning interferometer and a time-of-flight radar (denominated refractometer). The first, using two scanning beams, can provide a plasma density profile every 62.5 mu s. Two lasers (CO2/CO) are employed for compensation of mechanical vibration of optical components. The scanning component is a small mirror (phi=5 mm) tilting at 8 kHz. The oscillation is cancelled out by a second reflection on this mirror. The time-of-flight refractometer is a two-frequency radar (51.5 GHz and 60.5 GHz) which measures the plasma refractive index from the delay time of an RF pulse that goes through the plasma and is reflected back by the metallic vacuum vessel. The line density and the profile peaking by both diagnostics are in good agreement (C) 2012 Elsevier B.V. All rights reserved.

The design of diagnostics for the Frascati Tokamak Upgrade (FTU) is challenging because of the compactness of the machine (8-cm-wide ports) and the low operating temperatures requiring the presence of a cryostat. Nevertheless, a rather complete diagnostic system has been progressively installed. The basic systems include a set of magnetic probes, various visible and ultraviolet spectrometers, electron cyclotron emission (ECE) for electron temperature profiles measurements and electron tails monitoring, far-infrared and CO{sub 2} interferometry, X-ray (soft and hard) measurements, a multichord neutron diagnostics (with different type detectors), and a Thomson scattering system. Some diagnostics specific to the FTU physics program have been used such as microwave reflectometry for turbulence studies, edge-scanning Langmuir probes for radio-frequency coupling assessment, oblique ECE, and a fast electron bremsstrahlung (FEB) camera for lower hybrid current drive-induced fast electron tails.These systems are briefly reviewed in this paper. Further developments including a scanning CO{sub 2} laser two-color interferometer, two FEB cameras for tomographic analysis, a motional Stark effect system, and a collective Thomson scattering system are also described.

The effects of a soluble trimeric CD40 ligand (CD40L) agonist on the expression of CD4 and CCR5 and on human immunodeficiency virus (HIV) type 1 entry into and replication in human macrophages were investigated. CD40L increased the number of CD4 and CCR5 antibody-binding sites and the percentage of CD4- and CCR5-expressing cells. Infection of CD40L-stimulated macrophages with HIV-1 resulted in a marked increase of viral DNA with respect to controls, as demonstrated by polymerase chain reaction assay. HIV-1 p24 antigen analysis showed that peak viral production did not differ between CD40L-stimulated macrophages and controls. However, because of a prolonged life span, overall viral output was increased in CD40L-stimulated cultures. In addition, CD40L down-regulated the antiviral efficacy of compounds that inhibit HIV-1 reverse transcriptase. In conclusion, CD40L stimulation of macrophages can contribute to plasma virus load and favor the establishment of a pool of latently infected macrophages that can be reactivated to release virus.

A multichannel reflectometer will be built for the new three-straps ICRF antenna of ASDEX Upgrade (AUG), to study the density behavior in front of it. Ten different accesses to the plasma are available for the three reflectometer channels that can be interchanged without breaking the machine vacuum. Frequency is scanned from 40 GHz to 68 GHz, in 10?s, which corresponds to a cut-off density ranging from 1018÷1019 m -3 in the Right cut-off of the X-mode propagation, for standard toroidal magnetic field values of AUG. © 2014 AIP Publishing LLC

Recent studies in vitro and in animals have suggested that ribavirin may potentiate the antihepatitis C virus (HCV) activity of interferon-alpha (IFN-alpha) by up-modulating the production of T cell-derived cytokines, such as interleukin (IL)-2 and IFN-gamma, which play a key role in the cellular immune response against HCV. To study the immune-modulatory mechanisms of ribavirin further, cytokine production by activated T cells and circulating cytokine levels were studied by FACS analysis and ELISA testing in 25 patients with chronic hepatitis C unresponsive to IFN-alpha, before and after treatment with either ribavirin plus IFN-alpha or IFN-alpha alone. After 16 weeks of treatment, both the expression of IFN-gamma by activated T cells and the blood levels of IFN-gamma, were significantly reduced with respect to pretreatment values in patients treated with ribavirin and IFN-alpha but not in those undergoing treatment with IFN-alpha alone. The expression of IFN-gamma was significantly lower in patients that gained normal ALT levels with respect to those that did not. No modification of the expression of IL-2, IL-4 and IL-10 was found before and after treatment in either group of patients. In conclusion, the results of this study do not support up-modulation of IFN-gamma and IL-2 production as the mechanism by which ribavirin potentiates IFN-alpha anti HCV activity. In addition, our findings suggest that ribavirin may exert an anti-inflammatory effect and may help reducing IFN-gamma-driven T cell activation and liver damage.

Background: The prognosis of chronic hepatitis depends on the progression of hepatic fibrosis. Aim: To investigate whether the antifibrotic drug colchicine, in combination with interferon-α has a role in the treatment of chronic hepatitis C. Methods: Sixty-five HCV–RNA positive patients with chronic hepatitis were randomized to receive interferon-α, 6 MU t.i.w. for 6 months followed by 3 MU t.i.w. for further 6 months, with or without the adjunct of colchicine, 1 mg o.d., 6 days a week, for 3 years. We report an interim analysis after the first 18 months. Results: Thirty-four patients received interferon-α and 31 received interferon-α and colchicine. The two groups were comparable for baseline data, including HCV–RNA levels, genotypes and histological grading/staging. Drop-outs and side-effects were similar. The proportion of patients who achieved alanine transaminase normalization or undetectable HCV–RNA at month 6 was higher in the interferon-α (68% and 47%, respectively) than in the interferon-α plus colchicine group (32% and 23%, P=0.004 and P=0.04, respectively). End-of-treatment biochemical and virological response occurred in 41% and 29% of the interferon-α and 19% and 10% of the combination group, respectively (P=0.05 and P=0.05). Sustained biochemical response occurred in 26% of the interferon-α and 6% of the interferon-α plus colchicine group (P=0.03), corresponding percentages of sustained HCV–RNA loss being 21% and 3% (P=0.04). Conclusions: The combination of colchicine and interferon-α worsens the effectiveness of interferon-α alone in HCV chronic hepatitis. These alarming findings prompted us to interrupt the trial at this stage.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has multiple effects on the antigen phenotype and function of macrophages. In this study we investigated the effect of GM-CSF on cytokine production by macrophages. We found that GM-CSF may modify the tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) response to lipopolysaccharide (LPS) through two different mechanisms. Relatively early in culture, GM-CSF increases the amount of cytokines synthesized by responding cells; this effect appears to be unrelated to modulation of CD14 expression and LPS-binding capacity. After prolonged incubation, GM-CSF up-regulates both CD14 expression and LPS-binding capacity, and the frequency of cytokine-producing cells. Release of CD14 in the culture supernatant was decreased in the presence of GM-CSF, suggesting that a reduced shedding was responsible for the effect of GM-CSF on CD14 expression. Enhancement of cytokine production was also observed in GM-CSF-treated macrophages after stimulation by phorbol 12-myristate 13-acetate (PMA), thus indicating that GM-CSF affects both CD14-dependent and -independent cytokine production. Finally, GM-CSF did not modulate the LPS- and PMA-induced production of IL-10 and IL-12. We conclude that GM-CSF may play a role in manipulating the activation-induced expression of pro-inflammatory cytokines by macrophages. Enhanced production of these cytokines could play an important role in the pathogenesis of Gram-negative septic shock syndrome and in defence against infectious agents.

Our objective was to determine the safety and the activity of thymosin-α1 (Tα1) plus interferon-α (IFN-α) and zidovudine in human immunodeficiency virus (HIV)-infected patients with CD4 counts between 200 and 500 cells/mm3. The study was multicentre, Phase II, randomized and open label. Patients were randomized to receive triple therapy, or zidovudine plus IFN-α, or zidovudine alone. Ninety-two patients were enrolled. After 12 months, in the triple combination group there was a median increase from baseline of 69 CD4 cells/mm3; a decrease of 52 cells/mm3 and of 65.5 cells/mm3 was seen in the zidovudine plus IFN-α and in the zidovudine monotherapy groups, respectively. In the triple combination arm the increase in mean CD4 counts was significantly greater than that observed in the other arms, particularly in patients with baseline CD4 counts less than 350 cells/mm3. The plasma HIV RNA load in triple therapy group showed a mean peak decrease from baseline of 16 000 copies/ml after 5 months (versus a decrease of 5000 copies/ml in the zidovudine monotherapy group) that was sustained at 12 months (versus a mean increase of 7000 copies/ml in the zidovudine monotherapy group at 12 months). The triple combination was superior to both the other arms in terms of virological and immunological response. Our study, although based on regimens of clearly sub-optimal antiretroviral potency, addressed the issue of combined therapy directed at two different targets: the HIV replicative cycle and the immune system. The use of immunomodulating agents deserves further investigation in the context of more potent antiretroviral combinations.

Background/Aims: In Egypt chronic liver disease is customarily attributed to Schistosoma mansoni infection. Anti-HCV antibodies are highly prevalent among Egyptian blood donors, yet little is known about the risk factors, pathogenicity and virological features of HCV and its association with schistosomiasis. We studied 135 adult patients with chronic liver disease living in the Alexandria governorate, mostly in rural areas of the Nile Delta. Methods: Evaluation included abdominal ultrasonography; detection of anti-HCV antibodies and markers of HBV and HDV infection; HCV-RNA assay by 5' untranslated region nested polymerase-chain-reaction and HCV genotyping by a line probe assay; serologic (anti-soluble egg antigen, anti-SEA) and parasitological examinations for Schistosoma mansoni infection; and liver biopsy, if not contraindicated. Results: Ninety-one (67%) patients had anti-HCV and 107 (85%) anti-SEA, 32 (30%) of whom excreted schistosomal eggs in stools. In addition, 21 (16%) patients had HBsAg, 86 (64%) anti-HBc and four (3%) anti-delta. Thus, many patients had evidence of multiple infections, double in 66% (anti-HCV and anti-SEA), triple in 33% (anti-HCV HBsAg and anti-SEA). Based on our diagnostic criteria, 25 (19%) patients had schistosomal portal fibrosis (anti-HCV positive in eight), 24 (18%) chronic hepatitis (anti-HCV positive in 19), 76 (56%) cirrhosis (anti-HCV positive in 58) and 10 hepatic tumors (anti-HCV positive in six). At multivariate analysis, the presence of anti-HCV was independently associated with previous parenteral anti-schistosomal therapy, a history of hematemesis and seropositivity for anti-HBc. Fifty (55%) of 91 anti-HCV positive sera had HCV-RNA, in 41 cases classified as genotype 4a. Detection of HCV-RNA was associated with a more severe liver disease and occurred less frequently in patients with a history of schistosomiasis. Conclucions: HCV infection with genotype 4a is the main cause of severe chronic liver disease in Egypt, where it is highly associated with schistosomiasis.

A real-time data acquisition and elaboration system is being implemented to control the new ECH launcher recently installed at FTU (Frascati Tokamak Upgrade). The system is aimed at controlling different kinds of magnetohydrodynamic instabilities, in particular the deleterious 312 and 211 (neoclassical) tearing modes, (N)TM, and the saw teeth period in order to prevent the seeding of NTMs. The complete system is presented here together with preliminary offline and real-time tests. (C) 2001 Elsevier Science. All rights reserved. (C) 2013 Published by Elsevier B.V.

This study investigates the effects of cysteamine alone and in association with zidovudine or didanosine on the replication of human immunodeficiency virus type 1 (HIV-1). More than 90% viral inhibition was obtained by 200 microM cysteamine in lymphocytes and 100 microM cysteamine in macrophages against 4 primary isolates and 2 laboratory strains of HIV-1. Polymerase chain reaction analysis demonstrated that cysteamine interferes with early steps of HIV-1 replication, before proviral DNA formation. The use of cysteamine in conjunction with zidovudine or didanosine brought about an additive antiviral effect without concomitant increases in toxicity. The concentrations of cysteamine that are effective against HIV-1 in vitro have been well tolerated over long periods by patients under treatment for cystinosis, an inherited disorder. These observations suggest that cysteamine alone or in combination with zidovudine or didanosine could be a new potential treatment of HIV-1 infection.

The basis of the cytopathic effect induced by a laboratory strain and several clinical isolates of human immunodeficiency virus (HIV) in human macrophages cultured in the presence of macrophage colony-stimulating factor was studied. Infected macrophages die of necrosis, the consequence of the production of mature virions in infected cells. Cell death can be prevented by antiviral compounds that interfere with the assembly and budding of virions. Programmed cell death (apoptosis), a potential mechanism of HIV-mediated cell death in CD4 T lymphocytes, does not occur in infected macrophages as shown by electron microscopy, cytofluorometric and gel electrophoretic DNA analysis, and nuclear fluorescent staining by Hoechst and terminal dUTP-nick-end-labeling (TUNEL) assay. The data suggest that macrophage killing by HIV may occur in vivo. Thus, combination therapies that include compounds that inhibit the cytopathic effect of HIV in macrophages should be considered for AIDS patients.

During the years 1992-1994, we tested 948 individuals from different population groups for HIV-1 and HIV-2 infections by ELISA and WB and for HCV infection by ELISA. Repeated ELISA reactivity for HIV was found in 2.12% of blood donors, 2.95% of fire brigade personnel and 1.61% of prisoners. Western blotting studies, however, showed that these samples were non-reactive or indeterminate to either HIV-1 or HIV-2. In contrast, anti-HCV antibodies were detected in 39% of fire brigade personnel, 31.4% of prisoners and 20.8% of blood donors. The analysis of risk factors for acquiring HCV infection showed a strong association between a past history of parenteral therapy for schistosomiasis and anti-HCV seropositivity (p < 0.0001). The implementation of preventive strategies is at the moment the mandatory choice to stop a further spread of the HCV infection. Meanwhile the same preventive measures could avoid spreading of the HIV disease.

The paper reports the results of laboratory testing of dense sandy gravel carried out on large dimension undisturbed samples, obtained by means of in situ freezing technique. The specimens, 290 mm in diameter and 600 mm high, have been subjected to undrained cyclic triaxial tests carried out in isotropically and anisotropically consolidated conditions aimed at investigating sandy gravel susceptibility to cyclic mobility and plastic strain accumulation during earthquake induced vibrations. The quality of the undisturbed samples was corroborated by comparing the field shear wave velocities against those inferred from bender element tests, carried out in the triaxial apparatus after the specimen consolidation. The cyclic tests were supported by a series of monotonic undrained and drained triaxial tests performed on isotropically and anisotropically consolidated specimens to help in their more rational interpretation. The tests yielded valuable information as to the susceptibility of the sandy gravel in hands to cyclic mobility and plastic strain accumulation during earthquake loading.

We have investigated the effects of combination therapy with thymosin alpha 1 and natural human lymphoblastoid interferon-alpha in human immunodeficiency virus infection and have shown that in vitro this combination treatment: (1) synergistically stimulated the cytotoxic activity against natural killer-sensitive target cells of lymphocytes collected from human immunodeficiency virus-infected donors and (2) did not interfere with the antiviral activity of zidovudine. We thus studied the effects of combination therapy with thymosin alpha 1, interferon-alpha and zidovudine in patients with CD4+ lymphocytes ranging from 200 to 500/mm3 in a randomized non-blinded study and found that the treatment was well tolerated after 12 months of therapy and was associated with a substantial increase in the number and function of CD4+ T cells. A similar effect was not observed in human immunodeficiency virus patients treated with zidovudine alone or associated with single agents. These data suggest the need for a controlled, double-blind clinical trial, recently initiated with the approval and the support of the Italian Ministry of Health.