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2. ampycloud: an open-source algorithm to determine cloud base heights and sky coverage fractions from ceilometer data

Author

F. P. A. Vogt, L. Foresti, D. Regenass, S. Réthoré, N. Tarin Burriel, M. Bibby, P. Juda, S. Balmelli, T. Hanselmann, P. du Preez, and D. Furrer

Subjects
Environmental engineering, TA170-171, Earthwork. Foundations, TA715-787
Abstract

Ceilometers are used routinely at aerodromes worldwide to derive the height and sky coverage fraction of cloud layers. This information, possibly combined with direct observations by human observers, contributes to the production of meteorological aerodrome reports (METARs). Here, we present ampycloud, a new algorithm, and its associated Python package for automatic processing of ceilometer data with the aim of determining the sky coverage fraction and base height of cloud layers above aerodromes. The ampycloud algorithm was developed at the Swiss Federal Office of Meteorology and Climatology (MeteoSwiss) as part of the AMAROC (AutoMETAR/AutoReport rOund the Clock) program to help in the fully automatic production of METARs at Swiss civil aerodromes. ampycloud is designed to work with no direct human supervision. The algorithm consists of three distinct, sequential steps that rely on agglomerative clustering methods and Gaussian mixture models to identify distinct cloud layers from individual cloud base hits reported by ceilometers. The robustness of the ampycloud algorithm stems from the first processing step, which is simple and reliable. It constrains the two subsequent processing steps that are more sensitive but also better suited to handling complex cloud distributions. The software implementation of the ampycloud algorithm takes the form of an eponymous, pip-installable Python package developed on GitHub and made publicly accessible.

Published
2024
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4. A friendly tool to remotely follow-up fusion machines experiments

Author

J.M. Theis, J. Signoret, and S. Balme

Subjects
Nuclear Energy and Engineering, Java, Event (computing), Computer science, Mechanical Engineering, Operating system, General Materials Science, Architecture, computer.software_genre, computer, Civil and Structural Engineering, computer.programming_language
Abstract

When the international collaborations gather around a project more and more geographically scattered participants, it is imperative for them to get tools to keep in touch with the laboratory hosting the experiment, to know about the ongoing operations or even to remotely participate in them. The CEA-IRFM developed ShotListener to meet these needs, which should appear for actual or future tokamaks. This Java application intercepts the main events of a discharge sequence and notifies the user with visual or sound alerts, allowing him to follow the distant experiments easily. An API based on an MDSplus server has been developed to insure communication with the local CODAC supervision system. This API translates the Tokamak events as MDSplus events, available for any subscribers. The java application ShotListener, available for Windows and Linux platforms as an auto-installable package, connects to the MDSplus server, subscribes to a list of shot events (customizable by the end-user) and sends a visual or sound alert when a selected event occurs. For example, depending on the selected events, the user can display an extract of the shots log or visualize the video of the pulse. This architecture is obviously suitable for any machine, as long as the specific API sending MDSplus events is implemented. The aim of this paper is to describe the detailed architecture of ShotListener, to present its different functionalities and to introduce some possible enhancements.

Published
2013

5. Enabling remote access to projects in a large collaborative environment

Author

H.S. Akpangny, Pär Strand, F. Iannone, S. Balme, and V. Pais

Subjects
Authentication, Java, business.industry, Computer science, Mechanical Engineering, Directory, Shibboleth, Nuclear Energy and Engineering, Lightweight Directory Access Protocol, Chaining, General Materials Science, Project management, business, Software engineering, Distributed File System, computer, Civil and Structural Engineering, computer.programming_language
Abstract

In the context of the Integrated Tokamak Modelling Task Force, a large number of software projects are made available to the task force members, including developers and end-users. This has been achieved through a combination of tools and technologies. The front-end is represented by a Java based portal system exposing a PHP project management system, GForge. These two applications are linked by a single sign-on mechanism, Shibboleth [1], and through secure HTTP [2] request rewriting, where appropriate. Furthermore, the underlying storage facility is an OpenAFS [3] distributed file system and the user base comes from both a network information server and an LDAP [4] directory. Security mechanisms are those of a distributed system, with multiple access points and protocols used for reading and writing data. The present paper presents the challenges of integrating these different technologies and programming languages into a single, working, application presented to its users as a web portal. Chaining of the tools is explored through the user perspective, with an in-depth overview of the background transitions between the various systems involved with regard to security requirements for the front-end nodes and the policies as seen by the users.

Published
2010

6. Real-Time Data Acquisition System for Control and Long-Pulse Operation in Tore Supra

Author

F. Leroux, P. Fejoz, P. Pastor, Y. Buravand, N. Ravenel, P. Spuig, and S. Balme

Subjects
Nuclear and High Energy Physics, Long pulse, Tokamak, Computer science, Mechanical Engineering, Real-time computing, Control (management), Magnetic confinement fusion, Tore Supra, law.invention, Real time data acquisition system, Nuclear magnetic resonance, Data acquisition, Nuclear Energy and Engineering, law, General Materials Science, Pulse-width modulation, Civil and Structural Engineering
Abstract

The tokamak Tore Supra was initially designed to operate long pulses, though the control and data acquisition systems nevertheless had to be upgraded to effectively perform these long-duration pulses. Continuous data acquisition was required for controlling the thermal phenomena, and huge amounts of data had to be handled, especially with the development of video imaging for the safety of the actively cooled vessel. A distributed architecture had to be developed so that real-time feedback could be implemented to ensure safe operation and to optimize the long-duration plasma performance. This paper briefly describes the initial control and data acquisition system and then reviews the developments and enhancements that were made to perform long pulses in Tore Supra.

Published
2009

7. EFDA‐fed: European federation among fusion energy research laboratories

Author

Horacio Fernandes, P. Lebourg, S. Balme, A. Pereira, J.M. Theis, K. Purahoo, K. Thomsen, A. Duarte, Andre Neto, J. Signoret, F. Oliveira, J. Kadlecsik, F. Reis, A. Portas, R. Castro, C. Rodríguez, and J. Vega

Subjects
Engineering management, Computer Networks and Communications, Computer science, Authorization, Single sign-on, Library and Information Sciences, Security layer, Laboratory testing, Simulation
Abstract

PurposeThe fusion energy research in Europe is developed by a set of laboratories of different countries and organisations. EFDA is an organisation whose main objective is to promote and improve the coordination and collaboration among these laboratories. This paper sets out to describe a working federation (EFDA‐Fed) that gathers EFDA (as organisation) and a set of fusion research laboratories: EURATOM/CIEMAT (Spain), CEA (France), JET (UK), IST (Portugal) and KFKI/HAS (Hungary).Design/methodology/approachTo achieve the objective a federation among all the organisations has been implemented based on PAPI as the authentication and authorization infrastructure that provides a security layer for accessing data among organisations.FindingsDuring the implementation of EFDA federation some improvements in distributed single sign on systems have been achieved such as the integration of JAVA applications and a single sign off mechanism.Practical implicationsUsers who belong to one of the federated organisations will be able to access from any IP address to resources located in any organisation of the federation in a secure way. On the other hand, new resources can be shared for federated users and access policies to these services can be implemented.Originality/valueThe paper describes a successful use of an open source technology (PAPI) for implementing a real multi‐organisation infrastructure for sharing services in a secure way, and integrating client applications and with a complete single sign off mechanism.

Published
2008

8. PAPI based federation as a test-bed for a common security infrastructure in EFDA sites

Author

W. Schiller, Horacio Fernandes, K. Purahoo, A. Duarte, Andre Neto, K. Thomsen, J. Kadlecsik, J.M. Theis, R. Castro, F. Oliveira, F. Reis, D. López, Jesús Vega, P. Lebourg, S. Balme, and A. Portas

Subjects
Java, business.industry, Computer science, Mechanical Engineering, Authorization, Access control, User management, Security policy, World Wide Web, Nuclear Energy and Engineering, General Materials Science, Single sign-on, business, computer, Civil and Structural Engineering, computer.programming_language
Abstract

Federated authentication and authorization systems provide several advantages to collaborative environments, for example, easy authentication integration, simpler user management, easier security policy implementation and quicker implementation of access control elements for new type of resources. A federation integrates different aspects that have to be coordinated by all the organizations involved. The most relevant are: definition of common schemas and attributes, definition of common policies and procedures, management of keys and certificates, management of common repositories and implementation of a home location service. A federation enabling collaboration of European sites has been put into operation. Four laboratories have been integrated and two more organizations (EFDA and KFKI/HAS) are finishing their integration. The federation infrastructure is based on Point of Access to Providers of Information (PAPI), a distributed authentication and authorization system. PAPI technology gives some important features, such as, single sign on for accessing to different resources, mobility for users, and compatibility with open and standard technologies: Java, JNLP protocol, XML-RPC and web technologies among others. In this article, the test-bed of EFDA federation is presented. Some examples of resources, securely shared inside the federation, are shown. Specific issues and experience gained in deploying federated collaboration systems will be addressed as well.

Published
2008

9. Using remote participation tools to improve collaborations

Author

J.M. Theis, N. Utzel, J How, and S. Balme

Subjects
Multimedia, business.industry, Computer science, Mechanical Engineering, Workspace, Space (commercial competition), computer.software_genre, Software, Nuclear Energy and Engineering, restrict, General Materials Science, The Internet, Instant messaging, business, computer, Civil and Structural Engineering
Abstract

Research on fusion requires effective collaboration between members who are not co-located in time and space. In order that distance should not restrict collaboration, this paper gives ideas and solutions to encourage and improve remote participation. This includes techniques for: 1. “On-line” discussions with internet via instant messaging (IM). 2. Sharing a publication space, using a collaborative web workspace. 3. Equipping dedicated meeting rooms with flexible communication and collaboration tools, hardware and software for multi-standard videoconferences. 4. Sharing presentations and supervision screens. 5. Participating remotely to experiments.

Published
2005

10. Nanovecteurs de médicaments et nanofiltration par membrane biomimétique

Author

Duverger, Eric, Picaud, F., Kraszewski, S., Ramseyer, C., Duverger, E., S. Balme, T., M. Janot, J., Déjardin, P., Henn, F., Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), and Duverger, Eric

Subjects
[INFO.INFO-MO] Computer Science [cs]/Modeling and Simulation, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation
Published
2011

11. Contribution of Tore Supra in preparation of ITER

Author

B. Saoutic, J. Abiteboul, L. Allegretti, S. Allfrey, J.M. Ané, T. Aniel, A. Argouarch, J.F. Artaud, M.H. Aumenier, S. Balme, V. Basiuk, O. Baulaigue, P. Bayetti, A. Bécoulet, M. Bécoulet, M.S. Benkadda, F. Benoit, G. Berger-by, J.M. Bernard, B. Bertrand, P. Beyer, A. Bigand, J. Blum, D. Boilson, G. Bonhomme, H. Bottollier-Curtet, C. Bouchand, F. Bouquey, C. Bourdelle, S. Bourmaud, C. Brault, S. Brémond, C. Brosset, J. Bucalossi, Y. Buravand, P. Cara, V. Catherine-Dumont, A. Casati, M. Chantant, M. Chatelier, G. Chevet, D. Ciazynski, G. Ciraolo, F. Clairet, M. Coatanea-Gouachet, L. Colas, L. Commin, E. Corbel, Y. Corre, X. Courtois, R. Dachicourt, M. Dapena Febrer, M. Davi Joanny, R. Daviot, H. De Esch, J. Decker, P. Decool, P. Delaporte, E. Delchambre, E. Delmas, L. Delpech, C. Desgranges, P. Devynck, T. Dittmar, L. Doceul, D. Douai, H. Dougnac, J.L. Duchateau, B. Dugué, N. Dumas, R. Dumont, A. Durocher, F.X. Duthoit, A. Ekedahl, D. Elbeze, M. El Khaldi, F. Escourbiac, F. Faisse, G. Falchetto, M. Farge, J.L. Farjon, M. Faury, N. Fedorczak, C. Fenzi-Bonizec, M. Firdaouss, Y. Frauel, X. Garbet, J. Garcia, J.L. Gardarein, L. Gargiulo, P. Garibaldi, E. Gauthier, O. Gaye, A. Géraud, M. Geynet, P. Ghendrih, I. Giacalone, S. Gibert, C. Gil, G. Giruzzi, M. Goniche, V. Grandgirard, C. Grisolia, G. Gros, A. Grosman, R. Guigon, D. Guilhem, B. Guillerminet, R. Guirlet, J. Gunn, O. Gurcan, S. Hacquin, J.C. Hatchressian, P. Hennequin, C. Hernandez, P. Hertout, S. Heuraux, J. Hillairet, G.T. Hoang, C. Honore, M. Houry, T. Hutter, P. Huynh, G. Huysmans, F. Imbeaux, E. Joffrin, J. Johner, L. Jourd'Heuil, Y.S. Katharria, D. Keller, S.H. Kim, M. Kocan, M. Kubic, B. Lacroix, V. Lamaison, G. Latu, Y. Lausenaz, C. Laviron, F. Leroux, L. Letellier, M. Lipa, X. Litaudon, T. Loarer, P. Lotte, S. Madeleine, P. Magaud, P. Maget, R. Magne, L. Manenc, Y. Marandet, G. Marbach, J.L. Maréchal, L. Marfisi, C. Martin, G. Martin, V. Martin, A. Martinez, J.P. Martins, R. Masset, D. Mazon, N. Mellet, L. Mercadier, A. Merle, D. Meshcheriakov, O. Meyer, L. Million, M. Missirlian, P. Mollard, V. Moncada, P. Monier-Garbet, D. Moreau, P. Moreau, L. Morini, M. Nannini, M. Naiim Habib, E. Nardon, H. Nehme, C. Nguyen, S. Nicollet, R. Nouilletas, T. Ohsako, M. Ottaviani, S. Pamela, H. Parrat, P. Pastor, A.L. Pecquet, B. Pégourié, Y. Peysson, I. Porchy, C. Portafaix, M. Preynas, M. Prou, J.M. Raharijaona, N. Ravenel, C. Reux, P. Reynaud, M. Richou, H. Roche, P. Roubin, R. Sabot, F. Saint-Laurent, S. Salasca, F. Samaille, A. Santagiustina, Y. Sarazin, A. Semerok, J. Schlosser, M. Schneider, M. Schubert, F. Schwander, J.L. Ségui, G. Selig, P. Sharma, J. Signoret, A. Simonin, S. Song, E. Sonnendruker, F. Sourbier, P. Spuig, P. Tamain, M. Tena, J.M. Theis, D. Thouvenin, A. Torre, J.M. Travère, E. Tsitrone, J.C. Vallet, E. Van Der Plas, A. Vatry, J.M. Verger, L. Vermare, F. Villecroze, D. Villegas, R. Volpe, K. Vulliez, J. Wagrez, T. Wauters, L. Zani, D. Zarzoso, X.L. Zou, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Science et Ingénierie des Matériaux et Procédés (SIMaP), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Dept. Accelerateurs - XFEL, Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Institut universitaire des systèmes thermiques industriels (IUSTI), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Matériaux et Mécanique des Composants (EDF R&D MMC), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Association EURATOM-CEA (CEA/DSM/DRFC), Département de Recherche sur la Fusion Contrôlée (DRFC), Laboratoire d'Interaction Laser Matière (LILM), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des Plasmas (LPP), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Ngee Ann Polytechnic, School of Engineering, Mechanical Engineering Division, ITER organization (ITER), CEA Cadarache, Centre de Thermique de Lyon (CETHIL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), CEA ISIS, Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Chimie de Clermont-Ferrand (ICCF), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-SIGMA Clermont (SIGMA Clermont)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche en Sciences et Techniques de la Ville - FR 2488 (IRSTV), Université de Nantes (UN)-École Centrale de Nantes (ECN)-EC. ARCHIT. NANTES-Université d'Angers (UA)-Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Eau et Environnement (IFSTTAR/GERS/EE), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-PRES Université Nantes Angers Le Mans (UNAM), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), Centre of Molecular and Structural Biomedicine (CBME)/Institute of Biotechnology and Bioengineering (IBB), University of Algarve [Portugal], Laboratoire Lasers, Plasmas et Procédés photoniques (LP3), Centre d'Histoire 'Espaces et Cultures' (CHEC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP), École des hautes études en sciences sociales (EHESS), Centre hospitalier universitaire de Nantes (CHU Nantes), Centre de Recherche en Cancérologie Nantes-Angers (CRCNA), Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM)-PRES Université Nantes Angers Le Mans (UNAM)-Hôtel-Dieu de Nantes-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hôpital Laennec-Centre National de la Recherche Scientifique (CNRS)-Faculté de Médecine d'Angers-Centre hospitalier universitaire de Nantes (CHU Nantes), Centre d'investigation clinique en cancérologie (CI2C), IFP Energies nouvelles (IFPEN), Matériaux, ingénierie et science [Villeurbanne] (MATEIS), Ecologie Systématique et Evolution (ESE), Centre National de la Recherche Scientifique (CNRS)-AgroParisTech-Université Paris-Sud - Paris 11 (UP11), Laboratoire d'Etude des Matériaux en Milieux Agressifs (LEMMA), Université de La Rochelle (ULR), CMCR des Massues, Croix rouge française, Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Laboratoire de Mécanique, Modélisation et Procédés Propres (M2P2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Réserve Naturelle Nationale Baie St-Brieuc, Réserves Naturelles de France-Réserves Naturelles de France, Géoazur (GEOAZUR 6526), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Direction des Jardins botaniques et zoologiques, Muséum national d'Histoire naturelle (MNHN), Department of Information Technology (INTEC), Ghent University [Belgium] (UGENT), Dipartimento di Ingegneria dell'Ambiente e per lo Sviluppo Sostenibile (DIASS), Dipartimento Ingn Ambiente & Sviluppo Soste, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2), Equipe Dynamique des Systemes Complexes, Université de Provence - Aix-Marseille 1, Technische Universität Braunschweig [Braunschweig], Laboratoire de physique des milieux ionisés et applications (LPMIA), Université Henri Poincaré - Nancy 1 (UHP)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche en Cancérologie de Lyon (UNICANCER/CRCL), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre Léon Bérard [Lyon], Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Service de Chimie Physique (SCP), Laboratoire des Adaptations Physiologiques aux Activités Physiques (LAPHAP), Université de Poitiers, Institut d'Electronique du Solide et des Systèmes ( InESS ), Centre National de la Recherche Scientifique ( CNRS ), Institut de Recherche sur la Fusion par confinement Magnétique ( IRFM ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Science et Ingénierie des Matériaux et Procédés ( SIMaP ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut polytechnique de Grenoble - Grenoble Institute of Technology ( Grenoble INP ) -Institut National Polytechnique de Grenoble ( INPG ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ), Laboratoire de l'Accélérateur Linéaire ( LAL ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Météorologie Dynamique (UMR 8539) ( LMD ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -École polytechnique ( X ) -École des Ponts ParisTech ( ENPC ) -Centre National de la Recherche Scientifique ( CNRS ) -Département des Géosciences - ENS Paris, École normale supérieure - Paris ( ENS Paris ) -École normale supérieure - Paris ( ENS Paris ), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies ( FEMTO-ST ), Université de Technologie de Belfort-Montbeliard ( UTBM ) -Ecole Nationale Supérieure de Mécanique et des Microtechniques ( ENSMM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Institut universitaire des systèmes thermiques industriels ( IUSTI ), Centre National de la Recherche Scientifique ( CNRS ) -Aix Marseille Université ( AMU ), EDF - R&D Department MMC and MAI, EDF R&D ( EDF R&D ), EDF ( EDF ) -EDF ( EDF ), Association EURATOM-CEA ( CEA/DSM/DRFC ), Département de Recherche sur la Fusion Contrôlée ( DRFC ), Laboratoire d'Interaction Laser Matière ( LILM ), Département de Physico-Chimie ( DPC ), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Laboratoire de Physique des Plasmas ( LPP ), Université Paris-Sud - Paris 11 ( UP11 ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Observatoire de Paris-École polytechnique ( X ) -Sorbonne Universités-PSL Research University ( PSL ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ), Institut Jean Lamour ( IJL ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Lorraine ( UL ), Département de Physique Nucléaire (ex SPhN) ( DPHN ), Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, ITER [St. Paul-lez-Durance], ITER, Centre de Thermique de Lyon ( CETHIL ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Electronique et des Technologies de l'Information ( CEA-LETI ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Grenoble Alpes [Saint Martin d'Hères], Institut de Chimie de Clermont-Ferrand ( ICCF ), Université Blaise Pascal - Clermont-Ferrand 2 ( UBP ) -Sigma CLERMONT ( Sigma CLERMONT ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Recherche en Sciences et Techniques de la Ville ( IRSTV ), Université d'Angers ( UA ) -Université de Nantes ( UN ) -École Centrale de Nantes ( ECN ) -Université de La Rochelle ( ULR ) -EC. ARCHIT. NANTES-Centre National de la Recherche Scientifique ( CNRS ), Eau et Environnement ( IFSTTAR/GERS/EE ), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux ( IFSTTAR ) -PRES Université Nantes Angers Le Mans ( UNAM ), Physique des interactions ioniques et moléculaires ( PIIM ), Aix Marseille Université ( AMU ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Intégration des Systèmes et des Technologies ( LIST ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Institut des Sciences de l'Evolution de Montpellier ( ISEM ), Université de Montpellier ( UM ) -Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Lasers, Plasmas et Procédés photoniques ( LP3 ), Centre d'Histoire 'Espaces et Cultures' ( CHEC ), Université Blaise Pascal - Clermont-Ferrand 2 ( UBP ), École des hautes études en sciences sociales ( EHESS ), Centre hospitalier universitaire de Nantes ( CHU Nantes ), Centre de Recherche en Cancérologie / Nantes - Angers ( CRCNA ), CHU Angers-Centre hospitalier universitaire de Nantes ( CHU Nantes ) -Hôtel-Dieu de Nantes-Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Hôpital Laennec-Centre National de la Recherche Scientifique ( CNRS ) -Faculté de Médecine d'Angers, Centre d'investigation clinique en cancérologie ( CI2C ), IFP Energies nouvelles ( IFPEN ), Matériaux, ingénierie et science [Villeurbanne] ( MATEIS ), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique ( CNRS ) -Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ), Ecologie Systématique et Evolution ( ESE ), Université Paris-Sud - Paris 11 ( UP11 ) -AgroParisTech-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Etude des Matériaux en Milieux Agressifs ( LEMMA ), Université de La Rochelle ( ULR ), Institut des Sciences Chimiques de Rennes ( ISCR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Ecole Nationale Supérieure de Chimie de Rennes-Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ), Croix-rouge française, Procédés et Ingénierie en Mécanique et Matériaux [Paris] ( PIMM ), Centre National de la Recherche Scientifique ( CNRS ) -Conservatoire National des Arts et Métiers [CNAM] ( CNAM ), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation ( IMEP-LAHC ), Centre National de la Recherche Scientifique ( CNRS ) -Université Savoie Mont Blanc ( USMB [Université de Savoie] [Université de Chambéry] ) -Institut National Polytechnique de Grenoble ( INPG ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut polytechnique de Grenoble - Grenoble Institute of Technology ( Grenoble INP ) -Université Grenoble Alpes ( UGA ), Laboratoire de Mécanique, Modélisation et Procédés Propres ( M2P2 ), Aix Marseille Université ( AMU ) -Ecole Centrale de Marseille ( ECM ) -Centre National de la Recherche Scientifique ( CNRS ), Géoazur ( GEOAZUR ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de la Côte d'Azur, Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Réserve de la Haute Touche, Muséum National d'Histoire Naturelle ( MNHN ), Department of Information Technology ( INTEC ), Ghent University [Belgium] ( UGENT ), Dipartimento di Ingegneria dell'Ambiente e per lo Sviluppo Sostenibile ( DIASS ), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier ( ICGM ICMMM ), Université Montpellier 1 ( UM1 ) -Université Montpellier 2 - Sciences et Techniques ( UM2 ) -Ecole Nationale Supérieure de Chimie de Montpellier ( ENSCM ) -Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS ), Physique des milieux ionisés et applications ( LPMIA ), Université Henri Poincaré - Nancy 1 ( UHP ) -Centre National de la Recherche Scientifique ( CNRS ), Centre de Recherche en Cancérologie de Lyon ( CRCL ), Université de Lyon-Université de Lyon-Centre Léon Bérard [Lyon]-Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Bureau de Recherches Géologiques et Minières (BRGM) ( BRGM ), Catalyse par les métaux, Institut de Chimie des Milieux et Matériaux de Poitiers ( IC2MP ), Université de Poitiers-Centre National de la Recherche Scientifique ( CNRS ) -Université de Poitiers-Centre National de la Recherche Scientifique ( CNRS ), Service de Chimie Physique ( SCP ), Laboratoire des Adaptations Physiologiques aux Activités Physiques ( LAPHAP ), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre Léon Bérard [Lyon]-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut National Polytechnique de Grenoble (INPG)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de La Rochelle (ULR)-EC. ARCHIT. NANTES-Centre National de la Recherche Scientifique (CNRS), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226, Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Physics, [PHYS]Physics [physics], Nuclear and High Energy Physics, [ PHYS ] Physics [physics], Plasma parameters, Ripple, Plasma, Tore Supra, Collisionality, Condensed Matter Physics, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, Computational physics, symbols.namesake, Nuclear magnetic resonance, Physics::Plasma Physics, 0103 physical sciences, symbols, Langmuir probe, Electron temperature, 010306 general physics, Power density
Abstract

International audience; Tore Supra routinely addresses the physics and technology of very long-duration plasma discharges, thus bringing precious information on critical issues of long pulse operation of ITER. A new ITER relevant lower hybrid current drive (LHCD) launcher has allowed coupling to the plasma a power level of 2.7 MW for 78 s, corresponding to a power density close to the design value foreseen for an ITER LHCD system. In accordance with the expectations, long distance (10 cm) power coupling has been obtained. Successive stationary states of the plasma current pro le have been controlled in real-time featuring (i) control of sawteeth with varying plasma parameters, (ii) obtaining and sustaining a `hot core' plasma regime, (iii) recovery from a voluntarily triggered deleterious magnetohydrodynamic regime. The scrape-off layer (SOL) parameters and power deposition have been documented during L-mode ramp-up phase, a crucial point for ITER before the X-point formation. Disruption mitigation studies have been conducted with massive gas injection, evidencing the difference between He and Ar and the possible role of the q = 2 surface in limiting the gas penetration. ICRF assisted wall conditioning in the presence of magnetic eld has been investigated, culminating in the demonstration that this conditioning scheme allows one to recover normal operation after disruptions. The effect of the magnetic eld ripple on the intrinsic plasma rotation has been studied, showing the competition between turbulent transport processes and ripple toroidal friction. During dedicated dimensionless experiments, the effect of varying the collisionality on turbulence wavenumber spectra has been documented, giving new insight into the turbulence mechanism. Turbulence measurements have also allowed quantitatively comparing experimental results with predictions by 5D gyrokinetic codes: numerical results simultaneously match the magnitude of effective heat diffusivity, rms values of density uctuations and wavenumber spectra. A clear correlation between electron temperature gradient and impurity transport in the very core of the plasma has been observed, strongly suggesting the existence of a threshold above which transport is dominated by turbulent electron modes. Dynamics of edge turbulent uctuations has been studied by correlating data from fast imaging cameras and Langmuir probes, yielding a coherent picture of transport processes involved in the SOL.

Published
2011

12. New developments of the TORE SUPRA acquisition system

Author

T Hutter, S. Balme, J.Y Pascal, Y. Buravand, B. Rothan, and B. Guillerminet

Subjects
Data processing, Tokamak, Computer science, business.industry, Mechanical Engineering, Electrical engineering, Tore Supra, Fusion power, law.invention, Data acquisition, Upgrade, Nuclear Energy and Engineering, law, Computer data storage, General Materials Science, Real-time data, business, Civil and Structural Engineering
Abstract

In order to support the heat-load of a continuous high power plasma, the upgrade of the first wall of the TORE SUPRA tokamak is now in progress and the first pulses are expected by July 2001. The TORE SUPRA acquisition system, originally conceived for long pulse data acquisition and processing, needs some improvements to meet new requirements such as fast and continuous data access, real time data processing where possible, more efficient post-pulse data processing.

Published
2001

13. Investigation of steady-state tokamak issues by long pulse experiments on Tore Supra

Author

Nicolas Crouseilles, R. Guirlet, J. Hourtoule, W. Xiao, J. L. Gardarein, Frédéric Schwander, E. Delchambre, A. Martinez, F. Bouquey, D. Boilson, M. Richou, L. Allegretti, V. Lamaison, T. Loarer, B. Lacroix, A. Vatry, W. Zwingmann, D. Ciazynski, J. Decker, P. Hertout, A. Bécoulet, R. Abgrall, M. Chatelier, B. Guillerminet, J. Lasalle, Yannick Marandet, M. Lipa, S. Nicollet, C. Reux, F. Benoit, E. Delmas, P. Reynaud, J. Y. Journeaux, F. Jullien, H. Bottollier-Curtet, Y. Buranvand, M. Schneider, D. Moreau, Karl Vulliez, M. Tena, P. Pastor, C. Le Niliot, S. Balme, G. Falchetto, V. Martin, L. Svensson, S. H. Hong, C. Laviron, M. Houry, J. M. Theis, S. Madeleine, T. Hutter, T. Salmon, L. Manenc, C. Bouchand, M. Davi, S. Rosanvallon, N. Dolgetta, Pascale Roubin, Eric Nardon, L.-G. Eriksson, B. Pégourié, D. Douai, O. Chaibi, Patrick Mollard, Didier Mazon, J. P. Gunn, Marie Farge, M. Prou, M. Thonnat, L. Begrambekov, J. Garcia, Philippe Ghendrih, L. Colas, Jacques Blum, J. Clary, P. Spuig, C. Gil, M. Kocan, Ph. Lotte, Paolo Angelino, B. Saoutic, M. Ottaviani, P. Devynck, X. Courtois, L. Doceul, Gilles Berger-By, Patrick Tamain, Marc Missirlian, K. Schneider, Yanick Sarazin, Lena Delpech, J.M. Ané, Pascale Hennequin, A. Durocher, Patrick Maget, P. Huynh, David Henry, P. Decool, Marc Goniche, F. Clairet, Julien Hillairet, A. Geraud, J. Signoret, Stéphane Heuraux, P. Bayetti, T. Gerbaud, X. L. Zou, Y. Peysson, H. Parrat, L. Million, Jérôme Bucalossi, S. Hacquin, Clarisse Bourdelle, F. Samaille, Bernard Bertrand, E. Sonnendruker, G. Chevet, A. Simonin, Ph. Cara, J. L. Maréchal, J. Johner, M. S. Benkadda, J. C. Hatchressian, R. Magne, J. Schlosser, A. Grosman, F. Brémond, R. Masset, Estelle Gauthier, S. Song, G. Giruzzi, M. Nannini, Caroline Hernandez, H.P.L. de Esch, P. Garibaldi, R. J. Dumont, Stanislas Pamela, M. Geynet, C. Nguyen, L. Zani, A. Casati, Cyrille Honoré, G. Gros, Fabrice Rigollet, A. Argouarch, Yann Corre, A. Marcor, H. Dougnac, E. Tsitrone, C. Grisolia, D. Pacella, Guillaume Latu, Céline Martin, T. Aniel, G. Darmet, R. Daviot, J.P. Martins, J. L. Farjon, P. Magaud, A. Ekedahl, Francesca Turco, D. Elbeze, P. Beyer, S. Carpentier, Roger Reichle, F. Faisse, X. Litaudon, R. Guigon, F.G. Rimini, F. Linez, L. Gargiulo, C. Fenzi-Bonizec, G. Marbach, Alexandre Torre, P. Monier-Garbet, N. Ravenel, Laure Vermare, J.-M. Travere, Xavier Garbet, R. Mitteau, H. Roche, C. Desgranges, V. Moncada, F. Villecroze, Jean-François Luciani, G. Ciraolo, F. Kazarian, J. Roth, C. Brosset, F. Saint-Laurent, H. Nehme, T. Parisot, Nicolas Fedorczak, F. Escourbiac, D. Guilhem, J. L. Duchateau, P. Moreau, O. Meyer, D. Yu, A. L. Pecquet, V. Petrzilka, E. Trier, Roland Sabot, G. T. A. Huysmans, G. T. Hoang, E. Joffrin, L. Meunier, P. Chantant, C. Portafaix, D. Voyer, J. C. Vallet, S. Salasca, J. L. Segui, A. Santagiustina, J.F. Artaud, G. Dunand, M. Lennholm, Frederic Imbeaux, V. Grandgirard, A. Escarguel, F. Leroux, Y. Lausenaz, P. Chappuis, V. Basiuk, F. Lott, Hinrich Lütjens, Sylvain Brémond, D. Villegas, Marina Becoulet, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de Physique Théorique [Palaiseau] (CPHT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Mathématiques de Bordeaux (IMB), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Association EURATOM-CEA (CEA/DSM/DRFC), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), and Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, fusion, Tokamak, MHD, Nuclear engineering, Cyclotron, Ultra-high vacuum, Electron, Tore Supra, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, law.invention, Nuclear physics, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, 52.35, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Physics, Magnetic confinement fusion, plasma heating, Plasma, Condensed Matter Physics, Magnetohydrodynamics
Abstract

The main results of the Tore Supra experimental programme in the years 2007–2008 are reported. They document significant progress achieved in the domain of steady-state tokamak research, as well as in more general issues relevant for ITER and for fusion physics research. Three areas are covered: ITER relevant technology developments and tests in a real machine environment, tokamak operational issues for high power and long pulses, and fusion plasma physics. Results presented in this paper include test and validation of a new, load-resilient concept of ion cycotron resonance heating antenna and of an inspection robot operated under ultra-high vacuum and high temperature conditions; an extensive experimental campaign (5 h of plasma) aiming at deuterium inventory and carbon migration studies; real-time control of sawteeth by electron cyclotron current drive in the presence of fast ion tails; ECRH-assisted plasma start-up studies; dimensionless scalings of transport and turbulence; transport experiments using active perturbation methods; resistive and fast-particle driven MHD studies. The potential role of Tore Supra in the worldwide fusion programme before the start of ITER operation is also discussed.

Published
2009

14. Evolution of the Tore Supra data acquisition system: towards the steady state

Author

R. Masset, L. Ducobu, Jean-Francois Artaud, J. Signoret, B. Guillerminet, Y. Buravand, M. Leluyer, B. Rothan, D. Elbeze, B. Couturier, B. Gagey, D. Moulin, and S. Balme

Subjects
Data acquisition, Software, Steady state (electronics), business.industry, Computer science, Continuous operation, Feedback control, Real-time computing, Control (management), Tore Supra, business, Data transmission
Abstract

In operation since 1988, the Tore Supra data acquisition system provides continuous data taking, storage and displays. But several limitations are observed, as the weak errors management, the performances of data transfer and of feedback control. The tied proprietary operating systems and as outcome, the lack of processors evolution prevent from upgrading the original system. So, the data acquisition system has been completely re-engineered aiming long pulse operations. It is based on a commercial package which provides all the basic modules to build a distributed on-line software from the data acquisition level up to the run control and data display. The continuous operation requests a few enhancements we explore in the last part.

Published
1997

15. Vietnam's New Order : International Perspectives on the State and Reform in Vietnam

Author

S. Balme, M. Sidel, S. Balme, and M. Sidel

Subjects
Law reform--Vietnam--Congresses, Law--Vietnam--Congresses
Abstract

This volume brings together distinguished international specialists on Vietnam and its reform process to explore the impact of reform in Vietnam on the Vietnamese state, society, and order, and Vietnam's international and regional environment.

Published
2007

16. TORE SUPRA DATA ANALYSIS FACILITIES

Author

R. Masset, V. Basiuk, Y. Buravand, A. Becoulet, M. Le Luyer, Yves Peysson, H. Demarthe, B. Saoutic, B. De Gentile, B. Guillerminet, B. Rothan, S. Balme, F. Hennion, and J. Signoret

Subjects
Hardware architecture, Tokamak, business.industry, Continuous flow, Computer science, Tore Supra, Megabyte, Visualization, law.invention, Shot (pellet), law, Component-based software engineering, business, Computer hardware
Abstract

The TORE SUPRA tokamak experiment was designed with a real-time acquisition system yielding a dense and continuous flow of data (about 15 Megabytes per shot). Very early on, physicists required tools allowing fast access, analysis, and visualization of these data. This paper will outline the hardware architecture along with the various software components which were developed and integrated to meet these needs.

Published
1993

17. EFDA-fed: European federation among fusion energy research laboratories.

Author

R. Castro, J. Vega, A. Portas, A. Pereira, S. Balme, A. Duarte, H. Fernandes, J. Kadlecsik, P. Lebourg, A. Neto, F. Oliveira, K. Purahoo, F. Reis, C. Rodriguez, J. Signoret, J.M. Theis, and K. Thomsen

Subjects
FUSION (Phase transformation), APPLICATION program interfaces, LEGAL authentication software, COMPUTER access control, JAVA programming language, GOVERNMENT laboratories
Abstract

The article focuses on the European Fusion Development Agreement (EFDA) federation which is an organisation of fusion research laboratories in Europe which include Commissariat à l'énergie atomique (CEA) of France, JET of Great Britain, and KFKI/HAS of Hungary. It states that Performance Application Programming Interface (PAPI) was implemented as the authentication and authorization infrastructure in all fusion research laboratories for security of data access in all the organisations. It mentions that improvements such as JAVA application integration and single sign off mechanism were achieved. It says that EFDA achieves central web file system, new data access paradigms, and video integration.

Published
2008

18. THE TORE SUPRA DATA ACQUISITION SYSTEM

Author

B. Rothan, F. Hennion, B. Guillerminet, and S. Balme

Subjects
Hardware architecture, Data acquisition, Computer science, Real-time computing, Tore Supra, Short duration
Abstract

The TORE SUPRA experiment (long duration plasma), needs a computer architecture, to allow data taking and real time processing in an efficient way. This paper describes this unconventionnal hardware architecture and the corresponding data acquisition system.

Published
1986

19. TJ-II operation tracking from Cadarache

Author

J. A. Muñoz, E. Ascasíbar, Eduardo Barrera, E. Sánchez, N. Utzel, Sergio Ripoll López, Mariano Ruiz, S. Balme, J. Vega, J.M. Theis, R. Castro, Y. Buravand, A. Pereira, A. Lopez, A. Mollinedo, D. López, P. Lebourg, A. Portas, and D. Machón

Subjects
Nuclear and High Energy Physics, Web server, Service (systems architecture), Authentication, Java, Computer science, 020209 energy, Mechanical Engineering, 02 engineering and technology, computer.software_genre, 01 natural sciences, 010305 fluids & plasmas, Videoconferencing, Nuclear Energy and Engineering, Server, 0103 physical sciences, Web page, 0202 electrical engineering, electronic engineering, information engineering, Operating system, General Materials Science, computer, Logbook, Civil and Structural Engineering, computer.programming_language
Abstract

The TJ-II remote participation system was designed to follow the TJ-II discharge production, even allowing the physicist in charge of operations to be in a remote location. The system has been based on both Web servers and Java technology. These elements were chosen for their open character, security properties, platform independence, and technological maturity. Web pages and Java applications permit users to access experimental systems, data servers, and the operation logbook. Security resources are provided by the PAPI system, a distributed authentication and authorization system. The TJ-II remote participation tools have allowed us to command and follow the stellarator operation from Cadarache. More than 1000 digitizer channels and more than 20 diagnostic control systems were remotely accessed from Web pages for monitoring/programming purposes. One Java application provided online information about the acquisition status of channels and acquisition cards. A second Java application showed temporal evolution signals that were refreshed in an automated way on the screen after each shot. A third Java application provided access to the operation logbook. In addition to these tools, we used the VRVS (virtual room videoconferencing system) (FUSION community, X-Point room) and the EFDA (European Fusion Development Agreement) Messenger Service for instant messaging (Jabber client).

20. Science and technology research and development in support to ITER and the Broader Approach at CEA

Author

A. Bécoulet, G.T. Hoang, J. Abiteboul, J. Achard, T. Alarcon, J. Alba-Duran, L. Allegretti, S. Allfrey, S. Amiel, J.M. Ané, T. Aniel, G. Antar, A. Argouarch, A. Armitano, J. Arnaud, D. Arranger, J.F. Artaud, D. Audisio, M. Aumeunier, E. Autissier, L. Azcona, A. Back, A. Bahat, X. Bai, B. Baiocchi, D. Balaguer, S. Balme, C. Balorin, O. Barana, D. Barbier, A. Barbuti, V. Basiuk, O. Baulaigue, P. Bayetti, C. Baylard, S. Beaufils, A. Beaute, M. Bécoulet, Z. Bej, S. Benkadda, F. Benoit, G. Berger-By, J.M. Bernard, A. Berne, B. Bertrand, E. Bertrand, P. Beyer, A. Bigand, G. Bonhomme, G. Borel, A. Boron, C. Bottereau, H. Bottollier-Curtet, C. Bouchand, F. Bouquey, C. Bourdelle, J. Bourg, S. Bourmaud, S. Brémond, F. Bribiesca Argomedo, M. Brieu, C. Brun, V. Bruno, J. Bucalossi, H. Bufferand, Y. Buravand, L. Cai, V. Cantone, B. Cantone, E. Caprin, T. Cartier-Michaud, A. Castagliolo, J. Belo, V. Catherine-Dumont, G. Caulier, J. Chaix, M. Chantant, M. Chatelier, D. Chauvin, J. Chenevois, B. Chouli, L. Christin, D. Ciazynski, G. Ciraolo, F. Clairet, R. Clapier, H. Cloez, M. Coatanea-Gouachet, L. Colas, G. Colledani, L. Commin, P. Coquillat, E. Corbel, Y. Corre, J. Cottet, P. Cottier, X. Courtois, I. Crest, R. Dachicourt, M. Dapena Febrer, C. Daumas, H.P.L. de Esch, B. De Gentile, C. Dechelle, J. Decker, P. Decool, V. Deghaye, J. Delaplanche, E. Delchambre-Demoncheaux, L. Delpech, C. Desgranges, P. Devynck, J. Dias Pereira Bernardo, G. Dif-Pradalier, L. Doceul, Y. Dong, D. Douai, H. Dougnac, N. Dubuit, J.-L. Duchateau, L. Ducobu, B. Dugue, N. Dumas, R. Dumont, A. Durocher, F. Duthoit, A. Ekedahl, D. Elbeze, A. Escarguel, J. Escop, F. Faïsse, G. Falchetto, J. Farjon, M. Faury, N. Fedorzack, P. Féjoz, C. Fenzi, F. Ferlay, P. Fiet, M. Firdaouss, M. Francisquez, B. Franel, J. Frauche, Y. Frauel, R. Futtersack, X. Garbet, J. Garcia, J. Gardarein, L. Gargiulo, P. Garibaldi, P. Garin, D. Garnier, E. Gauthier, O. Gaye, A. Geraud, M. Gerome, V. Gervaise, M. Geynet, P. Ghendrih, I. Giacalone, S. Gibert, C. Gil, S. Ginoux, L. Giovannangelo, S. Girard, G. Giruzzi, C. Goletto, R. Goncalves, R. Gonde, M. Goniche, R. Goswami, C. Grand, V. Grandgirard, B. Gravil, C. Grisolia, G. Gros, A. Grosman, J. Guigue, D. Guilhem, C. Guillemaut, B. Guillerminet, Z. Guimaraes Filho, R. Guirlet, J. P. Gunn, O. Gurcan, F. Guzman, S. Hacquin, F. Hariri, F. Hasenbeck, J.C. Hatchressian, P. Hennequin, C. Hernandez, P. Hertout, S. Heuraux, J. Hillairet, C. Honore, G. Hornung, M. Houry, I. Hunstad, T. Hutter, P. Huynh, V. Icard, F. Imbeaux, M. Irishkin, L. Isoardi, J. Jacquinot, J. Jacquot, G. Jiolat, M. Joanny, E. Joffrin, J. Johner, P. Joubert, L. Jourd'Heuil, M. Jouve, C. Junique, D. Keller, C. Klepper, D. Kogut, M. Kubič, F. Labassé, B. Lacroix, Y. Lallier, V. Lamaison, R. Lambert, S. Larroque, G. Latu, Y. Lausenaz, C. Laviron, R. Le, A. Le Luyer, C. Le Niliot, Y. Le Tonqueze, P. Lebourg, T. Lefevre, F. Leroux, L. Letellier, Y. Li, M. Lipa, J. Lister, X. Litaudon, F. Liu, T. Loarer, G. Lombard, P. Lotte, M. Lozano, J. Lucas, H. Lütjens, P. Magaud, P. Maget, R. Magne, J.-F. Mahieu, P. Maini, P. Malard, L. Manenc, Y. Marandet, G. Marbach, J.-L. Marechal, L. Marfisi, M. Marle, C. Martin, V. Martin, G. Martin, A. Martinez, P. Martino, R. Masset, D. Mazon, N. Mellet, L. Mercadier, A. Merle, D. Meshcheriakov, P. Messina, O. Meyer, L. Millon, M. Missirlian, J. Moerel, D. Molina, P. Mollard, V. Moncada, P. Monier-Garbet, D. Moreau, M. Moreau, P. Moreau, P. Morel, T. Moriyama, Y. Motassim, G. Mougeolle, D. Moulton, G. Moureau, D. Mouyon, M. Naim Habib, E. Nardon, V. Négrier, J. Nemeth, C. Nguyen, M. Nguyen, L. Nicolas, T. Nicolas, S. Nicollet, E. Nilsson, B. N'Konga, F. Noel, A. Nooman, C. Norscini, R. Nouailletas, P. Oddon, T. Ohsako, F. Orain, M. Ottaviani, M. Pagano, F. Palermo, S. Panayotis, H. Parrat, J.-Y. Pascal, C. Passeron, P. Pastor, J. Patterlini, K. Pavy, A.-L. Pecquet, B. Pégourié, C. Peinturier, T. Pelletier, B. Peluso, V. Petrzilka, Y. Peysson, E. Pignoly, R. Pirola, C. Pocheau, E. Poitevin, V. Poli, S. Poli, F. Pompon, I. Porchy, C. Portafaix, M. Preynas, P. Prochet, M. Prou, A. Ratnani, D. Raulin, N. Ravenel, S. Renard, B. Ricaud, M. Richou, G. Ritz, H. Roche, P. Roubin, C. Roux, K. Ruiz, F. Sabathier, R. Sabot, A. Saille, F. Saint-Laurent, R. Sakamoto, S. Salasca, T. Salmon, F. Samaille, S. Sanchez, A. Santagiustina, B. Saoutic, Y. Sarazin, P. Sardain, J. Schlosser, M. Schneider, J. Schwob, J. Segui, N. Seguin, G. Selig, D. Serret, J. Signoret, A. Simonin, M. Soldaini, B. Soler, C. Soltane, S. Song, F. Sourbier, J. Sparagna, P. Spitz, P. Spuig, A. Storelli, A. Strugarek, P. Tamain, M. Tena, J. Theis, O. Thomine, D. Thouvenin, A. Torre, L. Toulouse, J. Travère, E. Tsitrone, B. Turck, J. Urban, J.-C. Vallet, J. Vallory, A. Valognes, J. Van Helvoirt, S. Vartanian, J.-M. Verger, L. Vermare, C. Vermare, D. Vezinet, K. Vicente, J. Vidal, N. Vignal, T. Vigne, F. Villecroze, E. Villedieu, B. Vincent, B. Volpe, D. Volpe, R. Volpe, J. Wagrez, H. Wang, T. Wauters, O. Wintersdorff, E. Wittebol, B. Zago, L. Zani, D. Zarzoso, Y. Zhang, W. Zhong, X.L. Zou, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique [Palaiseau] (CPHT), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, Engineering, Tokamak, business.industry, Superconducting magnet, Tore Supra, Condensed Matter Physics, 7. Clean energy, 01 natural sciences, Phase (combat), 010305 fluids & plasmas, law.invention, Procurement, Runaway electrons, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, Systems engineering, 010306 general physics, business, ComputingMilieux_MISCELLANEOUS
Abstract

Équipe 107 : Physique des plasmas chauds; International audience; In parallel to the direct contribution to the procurement phase of ITER and Broader Approach, CEA has initiated research & development programmes, accompanied by experiments together with a significant modelling effort, aimed at ensuring robust operation, plasma performance, as well as mitigating the risks of the procurement phase. This overview reports the latest progress in both fusion science and technology including many areas, namely the mitigation of superconducting magnet quenches, disruption-generated runaway electrons, edge-localized modes (ELMs), the development of imaging surveillance, and heating and current drive systems for steady-state operation. The WEST (W Environment for Steady-state Tokamaks) project, turning Tore Supra into an actively cooled W-divertor platform open to the ITER partners and industries, is presented.

21. Secondary Nucleation of Aβ Revealed by Single-Molecule and Computational Approaches.

Author

Meyer N, Arroyo N, Roustan L, Janot JM, Charles-Achille S, Torrent J, Picaud F, and Balme S

Subjects
Humans, Spectrometry, Fluorescence methods, Single Molecule Imaging methods, Amyloid beta-Peptides metabolism, Amyloid beta-Peptides chemistry, Molecular Dynamics Simulation, Alzheimer Disease metabolism
Abstract

Understanding the mechanisms underlying amyloid-β (Aβ) aggregation is pivotal in the context of Alzheimer's disease. This study aims to elucidate the secondary nucleation process of Aβ42 peptides by combining experimental and computational methods. Using a newly developed nanopipette-based amyloid seeding and translocation assay, confocal fluorescence spectroscopy, and molecular dynamics simulations, the influence of the seed properties on Aβ aggregation is investigated. Both fragmented and unfragmented seeds played distinct roles in the formation of oligomers, with fragmented seeds facilitating the formation of larger aggregates early in the incubation phase. The results show that secondary nucleation leads to the formation of oligomers of various sizes and structures as well as larger fibrils structured in β-sheets. From these findings a mechanism of secondary nucleation involving two types of aggregate populations, one released and one growing on the mother fiber is proposed., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Published
2024
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22. Performance of Single Nanopore and Multi-Pore Membranes for Blue Energy.

Author

Baldelli M, Di Muccio G, Viola F, Giacomello A, Cecconi F, Balme S, and Chinappi M

Abstract

The salinity gradient power extracted from the mixing of electrolyte solutions at different concentrations through selective nanoporous membranes is a promising route to renewable energy. However, several challenges need to be addressed to make this technology profitable, one of the most relevant being the increase of the extractable power per membrane area. Here, the performance of asymmetric conical and bullet-shaped nanopores in a 50 nm thick membrane are studied via electrohydrodynamic simulations, varying the pore radius, curvature, and surface charge. The output power reaches ~60 pW per pore for positively charged membranes (surface charge σ w =160 mC/m 2 ) and ~30 pW for negatively charges ones, σ w =-160 mC/m 2 and it is robust to minor variations of nanopore shape and radius. A theoretical argument that takes into account the interaction among neighbour pores allows to extrapolate the single-pore performance to multi-pore membranes showing that power densities from tens to hundreds of W/m 2 can be reached by proper tuning of the nanopore number density and the boundary layer thickness. Our model for scaling single-pore performance to multi-pore membrane can be applied also to experimental data providing a simple tool to effectively compare different nanopore membranes in blue energy applications., (© 2024 Wiley-VCH GmbH.)

Published
2024
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23. Controlling Electroosmosis in Nanopores Without Altering the Nanopore Sensing Region.

Author

Baldelli M, Di Muccio G, Sauciuc A, Morozzo Della Rocca B, Viola F, Balme S, Bonini A, Maglia G, and Chinappi M

Abstract

Nanopores are powerful tools for single-molecule sensing of biomolecules and nanoparticles. The signal coming from the molecule to be analyzed strongly depends on its interaction with the narrower section of the nanopore (constriction) that may be tailored to increase sensing accuracy. Modifications of nanopore constriction have also been commonly used to induce electroosmosis, that favors the capture of molecules in the nanopore under a voltage bias and independently of their charge. However, engineering nanopores for increasing both electroosmosis and sensing accuracy is challenging. Here it is shown that large electroosmotic flows can be achieved without altering the nanopore constriction. Using continuum electrohydrodynamic simulations, it is found that an external charged ring generates strong electroosmosis in cylindrical nanopores. Similarly, for conical nanopores it is shown that moving charges away from the cone tip still results in an electroosmotic flow (EOF), whose intensity reduces increasing the diameter of the nanopore section where charges are placed. This paradigm is applied to engineered biological nanopores showing, via atomistic simulations and experiments, that mutations outside the constriction induce a relatively intense electroosmosis. This strategy provides much more flexibility in nanopore design since electroosmosis can be controlled independently from the constriction, which can be optimized to improve sensing accuracy., (© 2024 Wiley‐VCH GmbH.)

Published
2024
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24. Characterizing Prion-Like Protein Aggregation: Emerging Nanopore-Based Approaches.

Author

Meyer N, Torrent J, and Balme S

Abstract

Prion-like protein aggregation is characteristic of numerous neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. This process involves the formation of aggregates ranging from small and potentially neurotoxic oligomers to highly structured self-propagating amyloid fibrils. Various approaches are used to study protein aggregation, but they do not always provide continuous information on the polymorphic, transient, and heterogeneous species formed. This review provides an updated state-of-the-art approach to the detection and characterization of a wide range of protein aggregates using nanopore technology. For each type of nanopore, biological, solid-state polymer, and nanopipette, discuss the main achievements for the detection of protein aggregates as well as the significant contributions to the understanding of protein aggregation and diagnostics., (© 2024 The Authors. Small Methods published by Wiley‐VCH GmbH.)

Published
2024
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25. Influence of Seed structure on Volume distribution of α-Synuclein Oligomer at Early Stages of Aggregation using nanopipette.

Author

Charles-Achille S, Janot JM, Cayrol B, and Balme S

Subjects
Biological Assay, Seeds, alpha-Synuclein, Parkinson Disease
Abstract

Understanding α-synuclein aggregation is crucial in the context of Parkinson's disease. The objective of this study was to investigate the influence of aggregation induced by preformed seeding on the volume of oligomers during the early stages, using a label-free, single-molecule characterization approach. By utilizing nanopipettes of varying sizes, the volume of the oligomers can be calculated from the amplitude of the current blockade and pipette geometry. Further investigation of the aggregates formed over time in the presence of added seeds revealed an acceleration in the formation of large aggregates and the existence of multiple distinct populations of oligomers. Additionally, we observed that spontaneously formed seeds inhibited the formation of smaller oligomers, in contrast to the effect of HNE seeds. These results suggest that the seeds play a crucial role in the formation of oligomers and their sizes during the early stages of aggregation, whereas the classical thioflavin T assay remains negative., (© 2024 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

Published
2024
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26. Combining iontronic, chromatography and nanopipette for Aβ42 aggregates detection and separation.

Author

Moderne M, Abrao-Nemeir I, Meyer N, Du J, Charles-Achille S, Janot JM, Torrent J, Lepoitevin M, and Balme S

Subjects
Humans, Amyloid beta-Peptides chemistry, Peptide Fragments chemistry, Oligonucleotides, Nanopores, Alzheimer Disease
Abstract

In this work, we aim to capture, detect and analysis at single molecule level Aβ42 aggregates. To this end, two strategies of track-etched nanopore membranes functionalization were investigated. The first one uses an aptamer and requires only three steps, whereas the second strategy uses Lecanemab antibodies and requires six steps. Out of the two presented strategies, the second one was found to be the most suitable to detect Aβ42 aggregates using a quick current-voltage readout. The resulting single nanopore was then upscale to multipore membranes to capture the Aβ42 aggregates before analysis through them through a single-molecule approach. By comparing the species present in the retentate and filtrate, we confirmed the membrane's affinity for the larger Aβ42 aggregates present in the sample. We found that chromatographic membranes combined with an ionic diode for binary on/off readout are powerful tools for detecting rare biomarkers before single molecule analysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Published
2023
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27. Aβ42 fibril and non-fibril oligomers characterization using a nanopipette.

Author

Abrao-Nemeir I, Meyer N, Nouvel A, Charles-Achille S, Janot JM, Torrent J, and Balme S

Subjects
Humans, Peptide Fragments chemistry, Amyloid chemistry, Amyloid beta-Peptides chemistry, Alzheimer Disease
Abstract

The Aβ42 aggregates with different structures and morphology was investigated through a single molecule label-free technique. To this end, the quartz nanopipettes were functionalized with polyethylene glycol. The set of Aβ42- epigallocatechin-3-gallate fibrils with length (from 85 nm to 250 nm) obtained by sonication was detected. The comparison of experimental and computed value of the amplitude of relative current blockade using a geometrical model show that for fibrils longer than 80 nm, the discriminating parameter is their diameter. Then, non-fibril oligomers obtain from Aβ42(Osaka) aggregation at different time seed was investigated. The analysis of the amplitude of relative current blockade shows that detected oligomers are smaller than 30 nm regardless the aggregation time. In addition, the wide distributions of the dwell time suggests the polymorph character of the sample., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Published
2023
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28. Ultrasensitive Detection of Aβ42 Seeds in Cerebrospinal Fluid with a Nanopipette-Based Real-Time Fast Amyloid Seeding and Translocation Assay.

Author

Meyer N, Bentin J, Janot JM, Abrao-Nemeir I, Charles-Achille S, Pratlong M, Aquilina A, Trinquet E, Perrier V, Picaud F, Torrent J, and Balme S

Subjects
Amyloidogenic Proteins, Seeds, Levodopa, Quartz
Abstract

In this work, early-stage Aβ42 aggregates were detected using a real-time fast amyloid seeding and translocation (RT-FAST) assay. Specifically, Aβ42 monomers were incubated in buffer solution with and without preformed Aβ42 seeds in a quartz nanopipette coated with L-DOPA. Then, formed Aβ42 aggregates were analyzed on flyby resistive pulse sensing at various incubation time points. Aβ42 aggregates were detected only in the sample with Aβ42 seeds after 180 min of incubation, giving an on/off readout of the presence of preformed seeds. Moreover, this RT-FAST assay could detect preformed seeds spiked in 4% cerebrospinal fluid/buffer solution. However, in this condition, the time to detect the first aggregates was increased. Analysis of Cy3-labeled Aβ42 monomer adsorption on a quartz substrate after L-DOPA coating by confocal fluorescence spectroscopy and molecular dynamics simulation showed the huge influence of Aβ42 adsorption on the aggregation process.

Published
2023
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30. Investigation of α-Synuclein and Amyloid-β(42)-E22Δ Oligomers Using SiN Nanopore Functionalized with L-Dopa.

Author

Abrao-Nemeir I, Bentin J, Meyer N, Janot JM, Torrent J, Picaud F, and Balme S

Subjects
Protein Aggregates, Levodopa, Amyloid beta-Peptides metabolism, Heparin, Amyloid metabolism, alpha-Synuclein, Nanopores
Abstract

Solid-state nanopores are an emerging technology used as a high-throughput, label-free analytical method for the characterization of protein aggregation in an aqueous solution. In this work, we used Levodopamine to coat a silicon nitride nanopore surface that was fabricated through a dielectric breakdown in order to reduce the unspecific adsorption. The coating of inner nanopore wall by investigation of the translocation of heparin. The functionalized nanopore was used to investigate the aggregation of amyloid-β and α-synuclein, two biomarkers of degenerative diseases. In the first application, we demonstrate that the α-synuclein WT is more prone to form dimers than the variant A53T. In the second one, we show for the Aβ(42)-E22Δ (Osaka mutant) that the addition of Aβ(42)-WT monomers increases the polymorphism of oligomers, while the incubation with Aβ(42)-WT fibrils generates larger aggregates., (© 2022 The Authors. Chemistry - An Asian Journal published by Wiley-VCH GmbH.)

Published
2022
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31. Bio-Based Ceramic Membranes for Bacteria Removal from Water.

Author

Kamgang-Syapnjeu P, Njoya D, Kamseu E, Balme S, Bechelany M, and Soussan L

Abstract

Bio-based ceramic membranes were elaborated from kaolinite clays, coconut husks and eggshells to retain E. coli bacteria present in water intended for human consumption. Their characterization and removal performances are investigated in this work. These bio-ceramic membranes were obtained by heating the formulation containing 75% clay, 15% coconut husk and 10% eggshell at 900 °C or 1000 °C, at different temperature rates, to give S1, S2 and S3 materials. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), mercury porosimetry and scanning electron microscopy (SEM) were used to characterize these membranes. Water flux density, bacterial removal and biofouling were also assessed. Water flux density was shown to depend on material porosity. Bacteria retention was 90% (with 1 log-removal) for S1, 80% (with 0.7 log-removal) for S2 and 100% (with 3.3 log-removal) for S3. Membranes S1 and S2 presented reversible biofouling, while no fouling was evidenced for S3 in the tested conditions. This work shows that the best bio-ceramic membrane in terms of bacterial removal and flux density was S3. Its water flux density was 2123 ± 72 L/h/m 2 at an initial pressure of 0.2 bar. This material is particularly interesting because its production protocol is quite simple, fast and without the addition of chemical additives. Moreover, it can be used to efficiently remove bacteria from drinking water.

Published
2022
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32. Real-Time Fast Amyloid Seeding and Translocation of α-Synuclein with a Nanopipette.

Author

Meyer N, Janot JM, Torrent J, and Balme S

Abstract

The detection to α-synuclein (αS) assemblies as a biomarker of synucleinopathies is an important challenge for further development of an early diagnosis tool. Here, we present proof of concept real-time fast amyloid seeding and translocation (RT-FAST) based on a nanopipette that combines in one unique system a reaction vessel to accelerate the seed amplification and nanopore sensor for single-molecule αS assembly detection. RT-FAST allows the detection of the presence αS seeds WT and A53T variant in a given sample in only 90 min by adding a low quantity (35 μL at 100 nM) of recombinant αS for amplification. It also shows cross-seeding aggregation by adding mixing seeds A53T with WT monomers. Finally, we establish the dependence between the capture rate of aggregates by the nanopore sensor and the initial seed concentration from 200 pM to 2 pM, which promises further development toward a quantitative analysis of the initial seed concentration., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Published
2022
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33. Conical nanopores highlight the pro-aggregating effects of pyrimethanil fungicide on Aβ(1-42) peptides and dimeric splitting phenomena.

Author

Meyer N, Arroyo N, Baldelli M, Coquart N, Janot JM, Perrier V, Chinappi M, Picaud F, Torrent J, and Balme S

Subjects
Amyloid beta-Peptides, Peptide Fragments, Pyrimidines, Fungicides, Industrial toxicity, Nanopores
Abstract

The Aβ(1-42) aggregation is a key event in the physiopathology of Alzheimer's disease (AD). Exogenous factors such as environmental pollutants, and more particularly pesticides, can corrupt Aβ(1-42) assembly and could influence the occurrence and pathophysiology of AD. However, pesticide involvement in the early stages of Aβ(1-42) aggregation is still unknown. Here, we employed conical track-etched nanopore in order to analyse the Aβ(1-42) fibril formation in the presence of pyrimethanil, a widely used fungicide belonging to the anilinopyrimidine class. Our results evidenced a pro-aggregating effect of pyrimethanil on Aβ(1-42). Aβ(1-42) assemblies were successfully detected using conical nanopore coated with PEG. Using an analytical model, the large current blockades observed (>0.7) were assigned to species with size close to the sensing pore. The long dwell times (hundreds ms scale) were interpreted by the possible interactions amyloid/PEG using molecular dynamic simulation. Such interaction could leave until splitting phenomena of the dimer structure. Our work also evidences that the pyrimethanil induce an aggregation of Aβ(1-42) mechanism in two steps including the reorganization prior the elongation phase., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Published
2022
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34. Origin of Ultrahigh Rectification in Polyelectrolyte Bilayers Modified Conical Nanopores.

Author

Liu TJ, Ma T, Lin CY, Balme S, and Hsu JP

Abstract

The switching of "ON" and "OFF" states of an ionic diode is investigated by considering a conical nanopore partially functionalized two polyelectrolyte (PE) layers via layer-by-layer deposition. Through observing the inversion of its rectification behavior, we demonstrate the function of the PE bilayers in ionic transport regulation. The ionic diode exhibits an ultrahigh ion rectification at a low level of pH. In an aqueous NaCl solution at pH 2, for example, the ratio of the current at "ON" state and that at "OFF" state can be about 800 and 200 for 1 and 100 mM, respectively. This remarkable gating behavior can be explained by the anion-pump-induced ion accumulation in the neutral region as well as the depletion zone at the interface. Our results further demonstrate the possibility of achieving an ultrahigh rectification in an ionic diode having a unipolar-like configuration.

Published
2021
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35. Solid-state and polymer nanopores for protein sensing: A review.

Author

Meyer N, Abrao-Nemeir I, Janot JM, Torrent J, Lepoitevin M, and Balme S

Subjects
Adsorption, Peptides, Polymers, Proteins, Nanopores
Abstract

In two decades, the solid state and polymer nanopores became attractive method for the protein sensing with high specificity and sensitivity. They also allow the characterization of conformational changes, unfolding, assembly and aggregation as well the following of enzymatic reaction. This review aims to provide an overview of the protein sensing regarding the technique of detection: the resistive pulse and ionic diodes. For each strategy, we report the most significant achievement regarding the detection of peptides and protein as well as the conformational change, protein-protein assembly and aggregation process. We discuss the limitations and the recent strategies to improve the nanopore resolution and accuracy. A focus is done about concomitant problematic such as protein adsorption and nanopore lifetime., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Published
2021
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36. Adsorption of proteins on TiO 2 particles influences their aggregation and cell penetration.

Author

Vian R, Salehi H, Lapierre M, Cuisinier F, Cavaillès V, and Balme S

Subjects
Adsorption, Colloids chemistry, Food Additives, Gelatin chemistry, Humans, Lactoglobulins chemistry, Nanoparticles chemistry, Particle Size, Titanium chemistry
Abstract

TiO 2 nanoparticles known as E171 are one controversial food additive due to its potential toxicity. In this work, the main hypothesis is that the proteins adsorbed on the TiO 2 nanoparticles prevent their aggregation and favor the cell penetration. To do so, the TiO 2 nanoparticles were coated with gelatin and β-lactoglobulin to reach interfacial concentrations about 0.25 mg/mg and 0.32 mg/mg, respectively. The measurement of NP size showed that the protein coating improve the colloidal stability of TiO 2 nanoparticles. The FTIR analysis suggests that the β-lactoglobulin structure is modified after adsorption. The penetration of TiO 2 penetration inside human intestinal epithelial cells was shown and quantify by using confocal Raman microscopy. The promoting role of the protein coating on the cell penetration was demonstrated for both the gelatin and β-lactoglobulin. Finally, the results allow establishing a correlation between the ability of proteins to prevent NP aggregation and the cell penetration., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Published
2021
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37. Detection of Amyloid-β Fibrils Using Track-Etched Nanopores: Effect of Geometry and Crowding.

Author

Meyer N, Arroyo N, Janot JM, Lepoitevin M, Stevenson A, Nemeir IA, Perrier V, Bougard D, Belondrade M, Cot D, Bentin J, Picaud F, Torrent J, and Balme S

Subjects
Amyloid, Amyloid beta-Peptides, Humans, Kinetics, Alzheimer Disease, Nanopores
Abstract

Several neurodegenerative diseases have been linked to proteins or peptides that are prone to aggregate in different brain regions. Aggregation of amyloid-β (Aβ) peptides is recognized as the main cause of Alzheimer's disease (AD) progression, leading to the formation of toxic Aβ oligomers and amyloid fibrils. The molecular mechanism of Aβ aggregation is complex and still not fully understood. Nanopore technology provides a new way to obtain kinetic and morphological aspects of Aβ aggregation at a single-molecule scale without labeling by detecting the electrochemical signal of the peptides when they pass through the hole. Here, we investigate the influence of nanoscale geometry (conical and bullet-like shape) of a track-etched nanopore pore and the effect of molecular crowding (polyethylene glycol-functionalized pores) on Aβ fibril sensing and analysis. Various Aβ fibril samples that differed by their length were produced by sonication of fibrils obtained in the presence of epigallocatechin gallate. The conical nanopore functionalized with polyethylene glycol (PEG) 5 kDa is suitable for discrimination of the fibril size from relative current blockade . The bullet-like-shaped nanopore enhances the amplitude of the current and increases the dwell time, allowing us to well discern the fibrils. Finally, the nanopore crowded with PEG 20 kDa enhances the relative current blockade and increases the dwell time; however, the discrimination is not improved compared to the "bullet-shaped" nanopore.

Published
2021
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38. Discrimination of α-Thrombin and γ-Thrombin Using Aptamer-Functionalized Nanopore Sensing.

Author

Reynaud L, Bouchet-Spinelli A, Janot JM, Buhot A, Balme S, and Raillon C

Subjects
Nanotechnology, Proteins, Thrombin, Biosensing Techniques, Nanopores
Abstract

Protein detection and identification at the single-molecule level are major challenges in many biotechnological fields. Solid-state nanopores have raised attention as label-free biosensors with high sensitivity. Here, we use solid-state nanopore sensing to discriminate two closely related proteins, α-thrombin and γ-thrombin. We show that aptamer functionalization improves protein discrimination thanks to a significant difference in the relative current blockade amplitude. To enhance discrimination, we postprocessed the signals using machine learning and training algorithms and we were able to reach an accuracy of 98.8% using seven features and ensemble methods.

Published
2021
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39. Impact of surface state on polyethylene glycol conformation confined inside a nanopore.

Author

Arroyo N, Balme S, and Picaud F

Abstract

Solid-state nanopores are a promising platform for characterizing proteins. In order to improve their lifetime and prevent fouling, Polyethylene Glycol (PEG) grafting is one of the most efficient and low-cost solutions. Different models to calculate the PEG thickness do not consider their interaction with the nanopore inner surface nor the effect of confinement. Here, we investigate by molecular dynamic simulation the PEG conformation inside a nanopore in the case of hydrophobic and hydrophilic nanopores. Our results reveal that the nanopore inner surface plays a role in the PEG organization and, thus, in the speed of the salt constituent. The resulting pair interaction between PEG and its environment clearly shows a more important affinity for K + compared to Li + cations.

Published
2021
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40. Conformation of Polyethylene Glycol inside Confined Space: Simulation and Experimental Approaches.

Author

Ma T, Arroyo N, Marc Janot J, Picaud F, and Balme S

Abstract

The modification of the inner nanopore wall by polymers is currently used to change the specific properties of the nanosystem. Among them, the polyethylene glycol (PEG) is the most used to prevent the fouling and ensure the wettability. However, its properties depend mainly on the chain structure that is very difficult to estimate inside this confined space. Combining experimental and simulation approaches, we provide an insight to the consequence of the PEG presence inside the nanopore on the nanopore properties. We show, in particular, that the cation type in the electrolyte, together with the type of electrolyte (water or urea), is at the origin of the ion transport modification in the nanopore.

Published
2021
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41. Fabrication of 3D printed antimicrobial polycaprolactone scaffolds for tissue engineering applications.

Author

Radhakrishnan S, Nagarajan S, Belaid H, Farha C, Iatsunskyi I, Coy E, Soussan L, Huon V, Bares J, Belkacemi K, Teyssier C, Balme S, Miele P, Cornu D, Kalkura N, Cavaillès V, and Bechelany M

Subjects
Anti-Bacterial Agents pharmacology, Polyesters, Printing, Three-Dimensional, Silver pharmacology, Tissue Scaffolds, Metal Nanoparticles, Tissue Engineering
Abstract

Synthetic polymers are widely employed for bone tissue engineering due to their tunable physical properties and biocompatibility. Inherently, most of these polymers display poor antimicrobial properties. Infection at the site of implantation is a major cause for failure or delay in bone healing process and the development of antimicrobial polymers is highly desired. In this study, silver nanoparticles (AgNps) were synthesized in polycaprolactone (PCL) solution by in-situ reduction and further extruded into PCL/AgNps filaments. Customized 3D structures were fabricated using the PCL/AgNps filaments through 3D printing technique. As demonstrated by scanning electron microscopy, the 3D printed scaffolds exhibited interconnected porous structures. Furthermore, X-ray photoelectron spectroscopy analysis revealed the reduction of silver ions. Transmission electron microscopy along with energy-dispersive X-ray spectroscopy analysis confirmed the formation of silver nanoparticles throughout the PCL matrix. In vitro enzymatic degradation studies showed that the PCL/AgNps scaffolds displayed 80% degradation in 20 days. The scaffolds were cytocompatible, as assessed using hFOB cells and their antibacterial activity was demonstrated on Escherichia coli. Due to their interconnected porous structure, mechanical and antibacterial properties, these cytocompatible multifunctional 3D printed PCL/AgNps scaffolds appear highly suitable for bone tissue engineering., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Published
2021
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42. Enhancement of Podocyte Attachment on Polyacrylamide Hydrogels with Gelatin-Based Polymers.

Author

Abdallah M, Nagarajan S, Martin M, Tamer M, Faour WH, Bassil M, Cuisinier FJG, Gergely C, Varga B, Pall O, Miele P, Balme S, El Tahchi M, and Bechelany M

Abstract

Biological activities of cells such as survival and differentiation processes are mainly maintained by a specific extracellular matrix (ECM). Hydrogels have recently been employed successfully in tissue engineering applications. In particular, scaffolds made of gelatin methacrylate-based hydrogels (GelMA) showed great potential due to their biocompatibility, biofunctionality, and low mechanical strength. The development of a hydrogel having tunable and appropriate mechanical properties as well as chemical and biological cues was the aim of this work. A synthetic and biological hybrid hydrogel was developed to mimic the biological and mechanical properties of native ECM. A combination of gelatin methacrylate and acrylamide (GelMA-AAm)-based hydrogels was studied, and it showed tunable mechanical properties upon changing the polymer concentrations. Different GelMA-AAm samples were prepared and studied by varying the concentrations of GelMA and AAm (AAm 2.5% + GelMA 3% , AAm 5% + GelMA 3% , and AAm 5% + GelMA 5% ). The swelling behavior, biodegradability, physicochemical and mechanical properties of GelMA-AAm were also characterized. The results showed a variation of swelling capability and a tunable elasticity ranging from 4.03 to 24.98 kPa depending on polymer concentrations. Moreover, the podocyte cell morphology, cytoskeleton reorganization and differentiation were evaluated as a function of GelMA-AAm mechanical properties. We concluded that the AAm 2.5% + GelMA 3% hydrogel sample having an elasticity of 4.03 kPa can mimic the native kidney glomerular basement membrane (GBM) elasticity and allow podocyte cell attachment without the functionalization of the gel surface with adhesion proteins compared to synthetic hydrogels (PAAm). This work will further enhance the knowledge of the behavior of podocyte cells to understand their biological properties in both healthy and diseased states.

Published
2020
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43. Machine Learning to Improve the Sensing of Biomolecules by Conical Track-Etched Nanopore.

Author

Meyer N, Janot JM, Lepoitevin M, Smietana M, Vasseur JJ, Torrent J, and Balme S

Subjects
DNA analysis, Biosensing Techniques, Machine Learning, Nanopores
Abstract

Single nanopore is a powerful platform to detect, discriminate and identify biomacromolecules. Among the different devices, the conical nanopores obtained by the track-etched technique on a polymer film are stable and easy to functionalize. However, these advantages are hampered by their high aspect ratio that avoids the discrimination of similar samples. Using machine learning, we demonstrate an improved resolution so that it can identify short single- and double-stranded DNA (10- and 40-mers). We have characterized each current blockade event by the relative intensity, dwell time, surface area and both the right and left slope. We show an overlap of the relative current blockade amplitudes and dwell time distributions that prevents their identification. We define the different parameters that characterize the events as features and the type of DNA sample as the target. By applying support-vector machines to discriminate each sample, we show accuracy between 50% and 72% by using two features that distinctly classify the data points. Finally, we achieved an increased accuracy (up to 82%) when five features were implemented.

Published
2020
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44. Development of new biocompatible 3D printed graphene oxide-based scaffolds.

Author

Belaid H, Nagarajan S, Teyssier C, Barou C, Barés J, Balme S, Garay H, Huon V, Cornu D, Cavaillès V, and Bechelany M

Subjects
Animals, Bone and Bones cytology, Cell Line, Tumor, Humans, Mice, Osteoblasts cytology, Bone and Bones metabolism, Graphite chemistry, Osteoblasts metabolism, Printing, Three-Dimensional, Tissue Engineering, Tissue Scaffolds chemistry
Abstract

The aim of this work was to develop a bioresorbable, biodegradable and biocompatible synthetic polymer with good mechanical properties for bone tissue engineering applications. Polylactic acid (PLA) scaffolds were generated by 3D printing using the fused deposition modelling method, and reinforced by incorporation of graphene oxide (GO). Morphological analysis by scanning electron microscopy indicated that the scaffold average pore size was between 400 and 500 μm. Topography imaging revealed a rougher surface upon GO incorporation (Sa = 5.8 μm for PLA scaffolds, and of 9.9 μm for PLA scaffolds with 0.2% GO), and contact angle measurements showed a transition from a hydrophobic surface (pure PLA scaffolds) to a hydrophilic surface after GO incorporation. PLA thermomechanical properties were enhanced by GO incorporation, as shown by the 70 °C increase of the degradation peak (thermal gravimetric analysis). However, GO incorporation did not change significantly the melting point assessed by differential scanning calorimetry. Physicochemical analyses by X-ray diffraction and Raman spectroscopy confirmed the filler presence. Tensile testing demonstrated that the mechanical properties were improved upon GO incorporation (30% increase of the Young's modulus with 0.3% GO). Cell viability, attachment, proliferation and differentiation assays using MG-63 osteosarcoma cells showed that PLA/GO scaffolds were biocompatible and that they promoted cell proliferation and mineralization more efficiently than pure PLA scaffolds. In conclusion, this new 3D printed nanocomposite is a promising scaffold with adequate mechanical properties and cytocompatibility which may allow bone formation., Competing Interests: Declaration of competing interest The authors declare that they do not have any conflict of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Published
2020
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45. Mechanisms of Heparin-Induced Tau Aggregation Revealed by a Single Nanopore.

Author

Giamblanco N, Fichou Y, Janot JM, Balanzat E, Han S, and Balme S

Subjects
Alzheimer Disease genetics, Heparin adverse effects, Nanopores, tau Proteins genetics
Abstract

Protein aggregation is involved in many diseases, including Parkinson's and Alzheimer's. The latter is characterized by intraneuronal deposition of amyloid aggregates composed of the tau protein. Although large and insoluble aggregates are typically found in affected brains, intermediate soluble oligomers are thought to represent crucial species for toxicity and spreading. Nanopore sensors constitute an emerging technology that allows the detection of the size and populations of molecular assembly present in a sample. Here, we employed conical nanopores to obtain the particle distributions during tau aggregation. We identified three distinct populations, monomers, oligomers, and fibrils, which we could quantify along the aggregation process. By comparing tau wild type with a mutant carrying the disease-associated P301L mutation, we showed that the latter mutation promotes the formation of oligomers. We furthermore highlighted that the P301L mutation promotes fibril breakage. This work demonstrates that conical nanopore is a powerful tool to measure and quantify transient protein aggregate intermediates.

Published
2020
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46. Boron Nitride Based Nanobiocomposites: Design by 3D Printing for Bone Tissue Engineering.

Author

Belaid H, Nagarajan S, Barou C, Huon V, Bares J, Balme S, Miele P, Cornu D, Cavaillès V, Teyssier C, and Bechelany M

Abstract

Here, we produced a synthetic polymer having adequate biocompatibility, biodegradability, and bioresorbability, as well as mechanical properties for applications in bone tissue engineering. We used the fused deposition modeling (FDM) based 3D printing approach in order to produce biomimetic biodegradable scaffolds made of polylactic acid (PLA). We strengthened these scaffolds by addition of exfoliated boron nitride (EBN) as filler. We demonstrated the presence of EBN by physicochemical analysis using Raman spectroscopy and X-ray diffraction (XRD). Using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), we found that EBN incorporation did not influence the transition temperature, but reduced the polymer crystallinity. Scanning electron microscopy for morphology evaluation showed a mean scaffold pore size of 500 μm. EBN incorporation did not affect the scaffold mechanical properties (tensile test), but modified the surface roughness. Moreover, contact angle quantification indicated that the surface of PLA/EBN scaffolds was hydrophilic and that of PLA scaffolds hydrophobic. Finally, the results of the cytotoxicity, cell attachment, and proliferation experiments using MG-63 and MC3T3 cells indicated that PLA scaffolds filled with EBN were nontoxic and compatible with osteoblastic cells and also promoted the scaffold mineralization by MG-63 cells. Altogether, our results suggest that this 3D printed nanocomposite scaffold is suitable for tissue engineering.

Published
2020
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47. Dynamics of long hyaluronic acid chains through conical nanochannels for characterizing enzyme reactions in confined spaces.

Author

Ma T, Janot JM, and Balme S

Subjects
Hyaluronic Acid chemistry, Hyaluronoglucosaminidase chemistry, Models, Chemical, Nanopores
Abstract

This research reports the transport behaviors of long flexible polymers (hyaluronic acid) through long conical track-etched nanochannels with and without grafted enzymes. The impacts of the channel diameter and the polymer regimes in solution (dilute and semi-dilute) have been investigated. Without enzymes, the experimental results can be well explained by the analytical models of the scaling law of de Gennes. Then, the corresponding enzymes (hyaluronidase) were grafted inside the channel. When enzymes are located at the base side, polymers get degraded at the entrance and the degraded products are detected. When enzymes are grafted at the tip side, the extension of translocation duration due to the binding of substrate-enzyme is observed. This is for the first time that the enzymatic degradation reactions are characterized in situ at the single molecule level by nanopore technology.

Published
2020
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48. Polynucleotide differentiation using hybrid solid-state nanopore functionalizing with α-hemolysin.

Author

Bentin J, Balme S, and Picaud F

Subjects
Amino Acid Sequence genetics, Biomimetics, Hemolysin Proteins genetics, Hydrophobic and Hydrophilic Interactions, Molecular Dynamics Simulation, Nanopores ultrastructure, DNA chemistry, Hemolysin Proteins chemistry, Polynucleotides chemistry
Abstract

We report results from full atomistic molecular dynamics simulations on the properties of biomimetic nanopores. This latter result was obtained through the direct insertion of an α-hemolysin protein inside a hydrophobic solid-state nanopore. Upon translocation of different DNA strands, we demonstrate here that the theoretical system presents the same discrimination properties as the experimental one obtained previously. This opens an interesting way to promote the stability of a specific protein inside a solid nanopore to develop further biomimetic applications for DNA or protein sequencing.

Published
2020
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49. Tunable Current Rectification and Selectivity Demonstrated in Nanofluidic Diodes through Kinetic Functionalization.

Author

Lin CY, Ma T, Siwy ZS, Balme S, and Hsu JP

Abstract

The possibility of tuning the current rectification and selectivity in nanofluidic diodes is demonstrated both experimentally and theoretically through dynamically functionalizing a conical nanopore with poly-l-lysine. We identified an optimum functionalization time equivalent to optimum modification depth that assures the highest rectification degrees. Results showed that the functionalization time-dependent rectification behavior of nanofluidic diodes is dominated by the properties of current at positive voltages that in our electrode configuration indicate the "on" state of the diode and accumulation of ions in the nanopore. The functionalization time also tunes the ion selectivity of the diode. If the functionalization time is sufficiently short, an unusual depletion of counterions near the bipolar interface results in a cation-selective nanopore. However, a further increase in the duration of functionalization renders a nanopore that is an anion-selective nanopore. The dynamic functionalization presented in this Letter enables tuning ion selectivity of nanopores.

Published
2020
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50. Impact of polyelectrolytes on lysozyme properties in colloidal dispersions.

Author

Ndour M, Janot JM, Soussan L, Bouaziz Z, Voiry D, and Balme S

Subjects
Acrylic Resins chemistry, Anti-Bacterial Agents pharmacology, Catalytic Domain, Chondroitin Sulfates chemistry, Colloids, Dextran Sulfate chemistry, Diffusion, Microbial Sensitivity Tests, Muramidase pharmacology, Polystyrenes chemistry, Sodium Chloride chemistry, Staphylococcus epidermidis drug effects, Staphylococcus epidermidis growth & development, Anti-Bacterial Agents chemistry, Muramidase chemistry, Polyelectrolytes chemistry
Abstract

In this work, we investigated the impact of different polyelectrolytes (polyacrylic acid, polystyrene sulfonate, dextran sulfate, and chondroitin sulfate) on lysozyme properties when they form colloidal complexes. To this aim, we characterized (i) the size and stability of the different polyelectrolyte-lysozyme complexes upon addition of NaCl (different concentrations) by diffusion light scattering, and (ii) the structure and accessibility of lysozyme active site in such complexes by fluorescence quenching and time resolved fluorescence analysis. We then used these results to explain the antibacterial activity variations among colloidal complexes and compared with free lysozyme. Our findings show that colloidal complexes that are more prone to swelling (i.e., lysozyme complexed with polystyrene sulfonate) are less stable upon salt addition. In these colloids, the enzymatic site is also more accessible. However, the antibacterial activity does not depend on the swelling properties because no large structural modification of the active site occurs., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Published
2019
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