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131 results on '"Y.Y. Chen"'

1. Corrosion behavior and oxide layer of selective-laser-melted Al-Mg-Sc-Zr alloy in marine atmospheric environment with different Cl−concentration

Author

Y.X. Chen, D.Y. Lin, X.L. Shen, Y.Y. Chen, X.J. Xia, B. Zhang, S.Q. Bao, B. Zhao, and Y.J. Lu

Subjects
Marine atmospheric environment, Al-Mg-Sc-Zr alloy, Cl− ion, Selective laser melting, Materials of engineering and construction. Mechanics of materials, TA401-492, Industrial electrochemistry, TP250-261
Abstract

In this study, the corrosion response of the Al-Mg-Sc-Zr alloy produced by selective laser-melting in marine atmospheric environments with different Cl− concentrations was studied by electrochemical and immersion. Microstructural observations showed the microstructural of Al-Mg- Sc -Zr alloy featured a double grain microstructure, making up a coarse and fine grain area. TEM showed that some white precipitates enriched with Zr and Sc were dispersed in the samples. The potentiodynamic polarization test indicated increasing the Cl− concentration led to a negative shift of corrosion potential and narrowed the potential range of the passive zone, which also caused the increase of corrosion current density value. The electrochemical impedance spectroscopy showed that higher Cl− concentration was greatly detrimental to generating a compact and dense oxide film on the Al-Mg-Sc-Zr alloys, as indicated by decreasing the resistance of the corrosion product layer and charge transfer resistance. The immersion test demonstrated that the samples suffered serious pit corrosion when the Cl− content increased to 1.5 and 3.5 wt%, showing a larger size and more depth of corrosion pits. This study is expected to provide data to determine the reliability of the SLM-manufactured Al-Mg-Sc-Zr alloy in marine atmospheric conditions.

Published
2024
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2. Development and manufacturing of beryllium-armoring ITER enhanced heat flux FW toward series production in China

Author

J.M. Chen, P.H. Wang, Y. Zhou, Q. Li, J.L. Li, J. Wu, J. Du, B. Yang, X.B. Zhu, H. Gao, D. Hu, Y.Y. Chen, Q.M. Wang, Z.H. Liu, K. Wang, S. Liu, L.M. Bao, and R. Hunt

Subjects
ITER first wall, full-scale prototype, armor bonding, manufacturing and testing, high heat flux test, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

ITER’s enhanced heat flux (EHF) first wall (FW) provides thermal shielding to the other components behind it and limits its plasma boundary, consequently bearing high surface heat loads up to 4.7 MW m ^−2 . China developed the EHF FW technologies in steady stages by making small mock-ups, semi-prototypes and a full-scale prototype (FSP), working toward series production at the Southwestern Institute of Physics. All the key technologies for bimetallic diffusion bonding, welding and assembly have been fully qualified. The Be armor tile size effects on thermal-fatigue performance have been evaluated using a pulsed high heat flux test with an EMS-400 electron beam facility. It was found that both the Be/CuCrZr bonding and its thermal-fatigue life are highly dependent on the tile size, and 12 × 12 mm ^2 Be tiles are acceptable for the required performance, either as individual tiles or in castellation by cutting larger ones. Small-scale mock-ups with such Be tiles survived 16 000 thermal cycles at 4.7 MW m ^−2 , while EHF FW fingers with 16 × 16 mm ^2 Be tiles demonstrated unstable performance. In contrast, only BE tiles larger than 24 × 12 mm ^2 showed reliable diffusion bonding with the CuCrZr heat sink by hot isostatic pressing and consequently should be castellated into smaller ones. The manufacturing of the FSP finger goes through complex thermal cycles, using CuCrZr alloys in age-strengthening plus cold-rolling states, enabling it to maintain its tensile strength to the level of 285 MPa and its mean grain size less than 100 µ m. The pipe welding for finger pairing and its assembly with the central beam are demonstrated, including enabling welding to be carried out twice for repair in a narrow space. The FSP showed good finger alignment, dimensional control and reliable vacuum tightness without any blockage of cooling channels.

Published
2024
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3. Expression, production, and renaturation of a functional single-chain variable antibody fragment (scFv) against human ICAM-1

Author

H. Sun, G.M. Wu, Y.Y. Chen, Y. Tian, Y.H. Yue, and G.L. Zhang

Subjects
Intercellular adhesion molecule-1, Single-chain variable antibody fragment, Expression, Purification, Renaturation, Biological activity, Medicine (General), R5-920, Biology (General), QH301-705.5
Abstract

Intercellular adhesion molecule-1 (ICAM-1) is an important factor in the progression of inflammatory responses in vivo. To develop a new anti-inflammatory drug to block the biological activity of ICAM-1, we produced a monoclonal antibody (Ka=4.19×10−8 M) against human ICAM-1. The anti-ICAM-1 single-chain variable antibody fragment (scFv) was expressed at a high level as inclusion bodies in Escherichia coli. We refolded the scFv (Ka=2.35×10−7 M) by ion-exchange chromatography, dialysis, and dilution. The results showed that column chromatography refolding by high-performance Q Sepharose had remarkable advantages over conventional dilution and dialysis methods. Furthermore, the anti-ICAM-1 scFv yield of about 60 mg/L was higher with this method. The purity of the final product was greater than 90%, as shown by denaturing gel electrophoresis. Enzyme-linked immunosorbent assay, cell culture, and animal experiments were used to assess the immunological properties and biological activities of the renatured scFv.

Published
2014
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6. Cardiovascular Nursing and Climate Change: A Call to Action From the CSANZ Cardiovascular Nursing Council

Author

Sally C. Inglis, Caleb Ferguson, Rebecca Eddington, Julee McDonagh, Chris J. Aldridge, Kimberley Bardsley, Dion Candelaria, Y.Y. Chen, Robyn A. Clark, Elizabeth Halcomb, Jeroen M. Hendriks, Louise D. Hickman, and Rochelle Wynne

Subjects
Pulmonary and Respiratory Medicine, Cardiology and Cardiovascular Medicine
Abstract

This Call to Action aims to provide key considerations for cardiovascular nursing, related to climate and environmental impacts. Strategies to optimise nursing preparation, immediate response and adaptation to climate emergencies are crucial to ensure those at greatest risk, including First Nations peoples, are protected from potentially avoidable harm. Professionals who manage climate consequences must also understand the impact of their care on the root cause of the problem.

Published
2022

10. Fruit abortion of ‘Guifei’ mango (Mangifera indicaL.) affected biosynthesis of carotenoid and polyphenols in pulp

Author

Z.C. Zhao, J.F. Huang, A.P. Gao, Y.Y. Chen, R.X. Luo, Z.G. Dang, and H.Y. Luo

Subjects
chemistry.chemical_classification, fungi, food and beverages, Ripening, Horticulture, Biology, Seedless fruit, chemistry.chemical_compound, chemistry, Polyphenol, Anthocyanin, Chlorophyll, embryonic structures, Mangifera, Cultivar, Carotenoid
Abstract

To investigate the effects of embryo abortion on fruit size and weight, fruit quality, chlorophyll, carotenoid, anthocyanin, flavonoid, and total polyphenols, the seeded fruit of mango (Mangifera indica L.) cultivar 'Guifei' were compared at the ripe stage. Seedless fruit had significantly smaller fruit size and lower fruit weight than seeded fruit in the cultivar. The experimental results suggested that embryo abortion at early stages of fruit ripening did not affect the concentration of total polyphenols in the pulp of matured fruit at green color or yellow color stages. However, the chlorophyll level decreased with ripening, lower in the abortion mango than in the normal mango. Carotenoid content increased throughout yellow stage and was significantly higher in the normal fruit compared to the abortion fruit. The concentrations of flavonoid were lower in the abortion fruit compared with normal fruit in the same color fruit. The expression of PSY and PDS was increased from green to yellow in abortion and normal mango. Expression of ANS and DFR was higher in the green color mango, in different development stages, and lower at the abortion stage in the yellow mango.

Published
2019
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13. A multilayer structure shear lag model applied in the tensile fracture characteristics of supersonic plasma sprayed thermal barrier coating systems based on digital image correlation

Author

Zhuo Wang, Haoyong Yang, M. Zhou, Xi Chen, Yanguo Wang, Cuiying Dai, Daining Fang, W.G. Mao, and Y.Y. Chen

Subjects
010302 applied physics, Digital image correlation, Materials science, Fracture mechanics, 02 engineering and technology, Surfaces and Interfaces, General Chemistry, engineering.material, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Surfaces, Coatings and Films, Thermal barrier coating, Fracture toughness, Brittleness, Coating, Shear (geology), 0103 physical sciences, Materials Chemistry, engineering, Composite material, 0210 nano-technology, Tensile testing
Abstract

We developed a multilayer structure shear lag model used in analyzing tensile fracture behavior of supersonic plasma sprayed 8 wt% yttria-stabilized zirconia thermal barrier coatings (TBCs). The closed-form solutions of plane and shear stresses were deduced by using the shear lag model. Dynamic strain fields, cracking nucleation and propagation features of TBCs during tensions were in-situ monitored by non-contact digital image correlation (DIC) measurement system. The evolutions of plane and shear stresses in TBCs were estimated by the above closed-form solutions. Using in-situ measurement results of DIC, we further obtained the fracture strengths, interface shear strengths, fracture energy and fracture toughness of TBCs, and summarized the whole tensile fracture mechanisms of TBCs. This shear lag model with the aid of DIC is useful for measuring the mechanical properties of other novel multiple-layer structure brittle coating/ductile substrate systems.

Published
2018
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14. Critical exponents of the La(sub 0.7)Sr(sub 0.3)MnO(sub 3), La(sub 0.7)Ca(sub 0.3)MnO(sub 3), and Pr(sub 0.7)Ca(sub 0.3)MnO(sub 3) systems showing correlation between transport and magnetic properties

Author

Taran, Subhrangsu, Chaudhuri, B.K., Chatterjee, Sandip, H.D. Yang, Neeleshwar, S., and Y.Y. Chen

Subjects
Lanthanum -- Magnetic properties, Praseodymium -- Magnetic properties, Physics
Abstract

The analysis of the low-temperature de-magnetization data of the La(sub 0.7)Sr(sub 0.3)MnO(sub 3) (LSM), La(sub 0.7)Ca(sub 0.3)MnO(sub 3) (LCM), and Pr(sub 0.7)Ca(sub 0.3)MnO(sub 3) (PCM)systems helps in estimating the critical components beta, gamma and delta by using the modified Arrot plots. The results show that the critical components of the similar manganite systems vary depending on the ground-state behavior of the samples and it is well reflected from the resistivity and thermoelectric power data of these perovskite compounds.

Published
2005

15. Survival Prediction of Esophageal Cancer Using 3D Residual Autoencoder and Proportional Hazards Model

Author

Laisen Wang, W.J. Cai, Z.R. Li, Zhenyu Lin, Y.Y. Chen, B.Z. Gao, and R.Z. Mao

Subjects
Cancer Research, medicine.medical_specialty, Radiation, business.industry, Proportional hazards model, medicine.medical_treatment, Deep learning, Hazard ratio, Esophageal cancer, medicine.disease, Autoencoder, Radiation therapy, Oncology, Feature (computer vision), Medicine, Radiology, Nuclear Medicine and imaging, Artificial intelligence, Radiology, business, Survival rate
Abstract

Purpose/Objective(s) Survival prediction of esophageal cancer is a difficult task for doctors looking to make personalized cancer treatment plan. Also, explicitly-designed handcrafted features obtained from medical images need prior medical knowledge which is usually limited and incomplete, and yields unsatisfying survival prediction. To address these challenges, we propose a novel and efficient deep survival learning network for evaluating clinical outcome prior to radiotherapy. Materials/Methods Three hundred twenty-six patients diagnosed with thoracic esophageal squamous cell carcinoma between December 2010 and September 2017 were analyzed. We used a deep learning network to extract potential features from gross tumor volumes in CT scans. For the first time, we integrate deep representations extracted from network above with dose information as feature signatures. A survival prediction model was generated to reliably predict a hazard ratio of patients with esophageal cancer. The model used Cox proportional hazards to model interactions between a patient's feature signatures and clinical outcome. The accuracy (concordance index [CI]) of this model subsequently was compared with the conventional technique. Results The experiments were performed using a combination of data from two input sources: deep features from CT (CI = 0.686) and dose information (CI = 0.576). Specifically, the fusion of them (CI = 0.702) significantly improved the performance of prediction comparing to using just one of them. The majority of models demonstrated improved accuracy compared with corresponding conventional models for survival predictions. Furthermore, experimental results demonstrated that the optimal model achieved concordance index of 0.702 which outperformed state-of-the-art methods using simpler and more accessible data. Conclusion This study provided a novel method for accurately predicting patient hazard ratios for use in esophageal cancer treatments. Performance improved when more types of data were integrated in the input of our model. The prognosis prediction model can help clinical work to judge the survival rate. This study offered a new avenue for personalized treatment and survival prognosis of esophageal cancer based on deep learning technology.

Published
2021
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16. Spinal Anesthesia for Patients With Coronavirus Disease 2019 and Possible Transmission Rates in Anesthetists: Retrospective, Single-centre, Observational Cohort Study

Author

X. Yang, Y.Y. Liu, Q. Zhong, F. Zheng, Q. Lou, M. Ma, Hong Li, J.J. Zang, H.X. Jiang, Z. Li, Z.Z. Zhang, Y.F. Zou, Y.Y. Chen, L.J. Tang, and J.J. Ke

Subjects
Pediatrics, medicine.medical_specialty, Single centre, Coronavirus disease 2019 (COVID-19), business.industry, Transmission (medicine), Medicine, Spinal anesthesia, business, Cohort study
Published
2021
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17. Effect of the microstructure and residual stress on tribological behavior of induction hardened GCr15 steel

Author

Y.J. Cao, J.Q. Sun, F. Ma, Y.Y. Chen, X.Z. Cheng, X. Gao, and K. Xie

Subjects
Austenite, Materials science, Mechanical Engineering, Induction hardening, Metallurgy, 02 engineering and technology, Surfaces and Interfaces, Tribology, 021001 nanoscience & nanotechnology, Microstructure, Surfaces, Coatings and Films, Hardened steel, 020303 mechanical engineering & transports, 0203 mechanical engineering, Mechanics of Materials, Residual stress, Martensite, Hardening (metallurgy), Composite material, 0210 nano-technology
Abstract

A systematic experimental investigation was conducted to study the effects of microstructure and residual stress on the tribological behavior of induction hardened GCr15 steel. Dry sliding wear tests of the hardened steel had been performed using a reciprocating ball-on-flat apparatus under different normal loads of 20, 50, and 100 N. The results indicate that the quenched layer microstructure is composed of martensite and retained austenite. The analysis of worn surface and wear debris of quenched layer showed that the wear mechanism was mainly abrasive wear at low load and delamination wear at high load. Typically, the compressive stress in the hardening layer has a significant positive influence on the wear resistance whereas the tensile stress has a negative effect.

Published
2017
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18. Intravenous alteplase for stroke with unknown time of onset guided by advanced imaging: systematic review and meta-analysis of individual patient data

Author

Götz Thomalla, Florent Boutitie, Henry Ma, Masatoshi Koga, Peter Ringleb, Lee H Schwamm, Ona Wu, Martin Bendszus, Christopher F Bladin, Bruce C V Campbell, Bastian Cheng, Leonid Churilov, Martin Ebinger, Matthias Endres, Jochen B Fiebach, Mayumi Fukuda-Doi, Manabu Inoue, Timothy J Kleinig, Lawrence L Latour, Robin Lemmens, Christopher R Levi, Didier Leys, Kaori Miwa, Carlos A Molina, Keith W Muir, Norbert Nighoghossian, Mark W Parsons, Salvador Pedraza, Peter D Schellinger, Stefan Schwab, Claus Z Simonsen, Shlee S Song, Vincent Thijs, Danilo Toni, Chung Y Hsu, Nils Wahlgren, Haruko Yamamoto, Nawaf Yassi, Sohei Yoshimura, Steven Warach, Werner Hacke, Kazunori Toyoda, Geoffrey A Donnan, Stephen M Davis, Christian Gerloff, Boris Raul Acosta, Karen Aegidius, Christian Albiker, Anna Alegiani, Miriam Almendrote, Angelika Alonso, Katharina Althaus, Pierre Amarenco, Hemasse Amiri, Bettina Anders, Adriana Aniculaesei, Jason Appleton, Juan Arenillas, Christina Back, Christian Bähr, Jürgen Bardutzky, Flore Baronnet-Chauvet, Rouven Bathe-Peters, Anna Bayer-Karpinska, Juan L. Becerra, Christoph Beck, Olga Belchí Guillamon, Amandine Benoit, Nadia Berhoune, Daniela Bindila, Julia Birchenall, Karine Blanc-Lasserre, Miguel Blanco Gonzales, Tobias Bobinger, Ulf Bodechtel, Eric Bodiguel, Urszula Bojaryn, Louise Bonnet, Benjamin Bouamra, Paul Bourgeois, Lorenz Breuer, Ludovic Breynaert, David Broughton, Raf Brouns, Sébastian Brugirard, Bart Bruneel, Florian Buggle, Serkan Cakmak, Ana Calleja, David Calvet, David Carrera, Hsin-Chieh Chen, Bharath Cheripelli, Tae-Hee Cho, Chi-un Choe, Lillian Choy, Hanne Christensen, Mareva Ciatipis, Geoffrey Cloud, Julien Cogez, Elisa Cortijo, Sophie Crozier, Dorte Damgaard, Krishna Dani, Beatrijs De Coene, Isabel De Hollander, Jacques De Keyser, Nina De Klippel, Charlotte De Maeseneire, Ann De Smedt, Maria del Mar Castellanos Rodrigo, Sandrine Deltour, Jelle Demeestere, Laurent Derex, Philippe Desfontaines, Ralf Dittrich, Anand Dixit, Laurens Dobbels, Valérie Domigo, Laura Dorado, Charlotte Druart, Kristina Hougaard Dupont, Anne Dusart, Rainer Dziewas, Matthias Ebner, Myriam Edjali-Goujon, Philipp Eisele, Salwa El Tawil, Ahmed Elhfnawy, Ana Etexberria, Nicholas Evans, Simon Fandler, Franz Fazekas, Sandra Felix, Jochen B. Fiebach, Jens Fiehler, Alexandra Filipov, Katharina Filipski, Robert Fleischmann, Christian Foerch, Ian Ford, Alexandra Gaenslen, Ivana Galinovic, Elena Meseguer Gancedo, Ramanan Ganeshan, Carlos García Esperón, Alicia Garrido, Thomas Gattringer, Olivia Geraghty, Rohat Geran, Stefan Gerner, Sylvie Godon-Hardy, Jos Göhler, Amir Golsari, Meritxell Gomis, David Gorriz, Verena Gramse, Laia Grau, Martin Griebe, Cristina Guerrero, Damla Guerzoglu, Sophie Guettier, Vincent Guiraud, Christoph Gumbinger, Ignaz Gunreben, Florian Haertig, Christian Hametner, Bernard Hanseeuw, Andreas Hansen, Jakob Hansen, Thomas Harbo, Andreas Harloff, Peter Harmel, Karl Georg Häusler, Florian Heinen, Valentin Held, Simon Hellwig, Dimitri Hemelsoet, Michael Hennerici, Juliane Herm, Sylvia Hermans, María Hernández, Jose Hervas Vicente, Niels Hjort, Cristina Hobeanu, Carsten Hobohm, Elmar Höfner, Katharina Hohenbichler, Marc Hommel, Julia Hoppe, Eva Hornberger, Carolin Hoyer, Xuya Huang, Nils Ipsen, Irina Isern, Lourdes Ispierto, Helle Iversen, Lise Jeppesen, Marta Jimenez, Jan Jungehülsing, Eric Jüttler, Dheeraj Kalladka, Bernd Kallmünzer, Arindam Kar, Lars Kellert, André Kemmling, Tobias Kessler, Usman Khan, Matthias Klein, Christoph Kleinschnitz, Matti Klockziem, Michael Knops, Luzie Koehler, Martin Koehrmann, Heinz Kohlfürst, Rainer Kollmar, Peter Kraft, Thomas Krause, Bo Kristensen, Jan M. Kröber, Natalia Kurka, Alexandre Ladoux, Patrice Laloux, Catherine Lamy, Emmanuelle Landrault, Arne Lauer, Claire Lebely, Jonathan Leempoel, Kennedy Lees, Anne Leger, Laurence Legrand, Lin Li, Anna-Mareike Löbbe, Frederic London, Elena Lopez-cancio, Matthias Lorenz, Stephen Louw, Caroline Lovelock, Manuel Lozano Sánchez, Giuseppe Lucente, Janos Lückl, Alain Luna, Kosmas Macha, Alexandre Machet, Daniel Mackenrodt, Dominik Madzar, Charles Majoie, Anika Männer, Vicky Maqueda, Jacob Marstrand, Alicia Martinez, Annika Marzina, Laura Mechthouff, Per Meden, Guy Meersman, Julia Meier, Charles Mellerio, Oliver Menn, Nadja Meyer, Dominik Michalski, Peter Michels, Lene Michelsen, Monica Millán Torne, Jens Minnerup, Boris Modrau, Sebastian Moeller, Anette Møller, Nathalie Morel, Fiona Moreton, Ludovic Morin, Thierry Moulin, Barry Moynihan, Anne K. Mueller, Keith W. Muir, Patricia Mulero, Sibu Mundiyanapurath, Johannes Mutzenbach, Simon Nagel, Oliver Naggara, Arumugam Nallasivan, Irene Navalpotro, Alexander H. Nave, Paul Nederkoorn, Lars Neeb, Hermann Neugebauer, Tobias Neumann-Haefelin, Stefan Oberndorfer, Christian Opherk, Lorenz Oppel, Catherine Oppenheim, Johannes Orthgieß, Leif Ostergaard, Perrine Paindeville, Ernest Palomeras, Verena Panitz, Bhavni Patel, Andre Peeters, Dirk Peeters, Anna Pellisé, Johann Pelz, Anthony Pereira, Natalia Pérez de la Ossa, Richard Perry, Salvador Petraza, Stéphane Peysson, Waltraud Pfeilschifter, Alexander Pichler, Alexandra Pierskalla, Hans-Werner Pledl, Sven Poli, Katrin Pomrehn, Marika Poulsen, Luis Prats, Silvia Presas, Elisabeth Prohaska, Volker Puetz, Josep Puig, Josep Puig Alcántara, Jan Purrucker, Veronique Quenardelle, Sankaranarayanan Ramachandran, Soulliard Raphaelle, Nicolas Raposo, Tilman Reiff, Michel Remmers, Pauline Renou, Martin Ribitsch, Hardy Richter, Martin Ritter, Thomas Ritzenthaler, Gilles Rodier, Christine Rodriguez-Regent, Manuel Rodríguez-Yáñez, Maria Roennefarth, Christine Roffe, Sverre Rosenbaum, Charlotte Rosso, Joachim Röther, Michal Rozanski, Noelia Ruiz de Morales, Francesca Russo, Matthieu Rutgers, Sharmilla Sagnier, Yves Samson, Josep Sánchez, Tamara Sauer, Jan H. Schäfer, Simon Schieber, Josef Schill, Dennis Schlak, Ludwig Schlemm, Sein Schmidt, Wouter Schonewille, Julian Schröder, Andreas Schulz, Johannes Schurig, Sönke Schwarting, Alexander Schwarz, Christopher Schwarzbach, Matthias Seidel, Alexander Seiler, Jochen Sembill, Joaquin Serena Leal, Ashit Shetty, Igor Sibon, Claus Z. Simonsen, Oliver Singer, Aravinth Sivagnanaratham, Ide Smets, Craig Smith, Peter Soors, Nikola Sprigg, Maximilian Spruegel, David Stark, Susanne Steinert, Sebastian Stösser, Markus Stuermlinger, Bart Swinnen, Ruben Tamazyan, Jose Tembl, Mikel Terceno Izaga, Emmanuel Touze, Thomas Truelsen, Guillaume Turc, Gaetane Turine, Serdar Tütüncü, Pippa Tyrell, Xavier Ustrell, Wilfried Vadot, Anne-Evelyne Vallet, Pauline Vallet, Lucie van den Berg, Sophie van den Berg, Cecile van Eendenburg, Robbert-Jan Van Hooff, Isabelle van Sloten, Peter Vanacker, Evelien Vancaester, Patrick Vanderdonckt, Yves Vandermeeren, Frederik Vanhee, Roland Veltkamp, Karsten Vestergaard, Alain Viguier, Dolores Vilas, Kersten Villringer, Dieke Voget, Jörg von Schrader, Paul von Weitzel, Elisabeth Warburton, Claudia Weber, Jörg Weber, Karl Wegscheider, Mirko Wegscheider, Christian Weimar, Karin Weinstich, Christopher Weise, Gesa Weise, Chris Willems, Klemens Winder, Matthias Wittayer, Marc Wolf, Martin Wolf, Valerie Wolff, Christian Wollboldt, Frank Wollenweber, Anke Wouters, Bertrand Yalo, Marion Yger, Nadia Younan, Laetita Yperzeele, Vesna Zegarac, Pia Zeiner, Ulf Ziemann, Thomas Zonneveld, Mathieu Zuber, Tsugio Akutsu, Junya Aoki, Shuji Arakawa, Ryosuke Doijiri, Yusuke Egashira, Yukiko Enomoto, Eisuke Furui, Konosuke Furuta, Seiji Gotoh, Toshimitsu Hamasaki, Yasuhiro Hasegawa, Teryuki Hirano, Kazunari Homma, Masahiko Ichijyo, Toshihiro Ide, Shuichi Igarashi, Yasuyuki Iguchi, Masafumi Ihara, Hajime Ikenouchi, Tsuyoshi Inoue, Ryo Itabashi, Yasuhiro Ito, Toru Iwama, Kenji Kamiyama, Shoko Kamiyoshi, Haruka Kanai, Yasuhisa Kanematsu, Takao Kanzawa, Kazumi Kimura, Jiro Kitayama, Takanari Kitazono, Rei Kondo, Kohsuke Kudo, Masayoshi Kusumi, Ken Kuwahara, Shoji Matsumoto, Hideki Matsuoka, Ban Mihara, Kazuo Minematsu, Ken Miura, Naomi Morita, Wataru Mouri, Kayo Murata, Yoshinari Nagakane, Taizen Nakase, Hiromi Ohara, Nobuyuki Ohara, Hideyuki Ohnishi, Hajime Ohta, Masafumi Ohtaki, Ryo Ohtani, Toshiho Ohtsuki, Hideo Ohyama, Takashi Okada, Yasushi Okada, Masato Osaki, Nobuyuki Sakai, Yoshiki Sanbongi, Naoshi Sasaki, Makoto Sasaki, Shoichiro Sato, Kenta Seki, Wataru Shimizu, Yoshiaki Shiokawa, Takashi Sozu, Junichiro Suzuki, Rieko Suzuki, Yasushi Takagi, Shunya Takizawa, Norio Tanahashi, Eijiro Tanaka, Ryota Tanaka, Yohei Tateishi, Tomoaki Terada, Tadashi Terasaki, Kenichi Todo, Azusa Tokunaga, Akira Tsujino, Toshihiro Ueda, Yoshikazu Uesaka, Mihoko Uotani, Takao Urabe, Masao Watanabe, Yoshiki Yagita, Yusuke Yakushiji, Keizo Yasui, Toshiro Yonehara, Shinichi Yoshimura, K. Aarnio, F. Alemseged, C. Anderson, T. Ang, M.L. Archer, J. Attia, P. Bailey, A. Balabanski, A. Barber, P.A. Barber, J. Bernhardt, A. Bivard, D. Blacker, C.F. Bladin, A. Brodtmann, D. Cadilhac, B.C.V. Campbell, L. Carey, S. Celestino, L. Chan, W.H. Chang, A. ChangI, C.H. Chen, C.-I. Chen, H.F. Chen, T.C. Chen, W.H. Chen, Y.Y. Chen, C.A. Cheng, E. Cheong, Y.W. Chiou, P.M. Choi, H.J. Chu, C.S. Chuang, T.C. Chung, L. Churilov, B. Clissold, A. Connelly, S. Coote, B. Coulton, E. Cowley, J. Cranefield, S. Curtze, C. D'Este, S.M. Davis, S. Day, P.M. Desmond, H.M. Dewey, C. Ding, G.A. Donnan, R. Drew, S. Eirola, D. Field, T. Frost, C. Garcia-Esperon, K. George, R. Gerraty, R. Grimley, Y.C. Guo, G. Hankey, J. Harvey, S.C. Ho, K. Hogan, D. Howells, P.M. Hsiao, C.H. Hsu, C.T. Hsu, C.-S. Hsu, J.P. Hsu, Y.D. Hsu, Y.T. Hsu, C.J. Hu, C.C. Huang, H.Y. Huang, M.Y. Huang, S.C. Huang, W.S. Huang, D. Jackson, J.S. Jeng, S.K. Jiang, L. Kaauwai, O. Kasari, J. King, T.J. Kleinig, M. Koivu, J. Kolbe, M. Krause, C.W. Kuan, W.L. Kung, C. Kyndt, C.L. Lau, A. Lee, C.Y. Lee, J.T. Lee, Y. Lee, Y.C. Lee, C. Levi, C.R. Levi, L.M. Lien, J.C. Lim, C.C. Lin, C.H. Lin, C.M. Lin, D. Lin, C.H. Liu, J. Liu, Y.C. Lo, P.S. Loh, E. Low, C.H. Lu, C.J. Lu, M.K. Lu, J. Ly, H. Ma, L. Macaulay, R. Macdonnell, E. Mackey, M. Macleod, J. Mahadevan, V. Maxwell, R. McCoy, A. McDonald, S. McModie, A. Meretoja, S. Mishra, P.J. Mitchell, F. Miteff, A. Moore, C. Muller, F. Ng, F.C. Ng, J-L. Ng, W. O'Brian, V. O'Collins, T.J. Oxley, M.W. Parsons, S. Patel, G.S. Peng, L. Pesavento, T. Phan, E. Rodrigues, Z. Ross, A. Sabet, M. Sallaberger, P. Salvaris, D. Shah, G. Sharma, G. Sibolt, M. Simpson, S. Singhal, B. Snow, N. Spratt, R. Stark, J. Sturm, M.C. Sun, Y. Sun, P.S. Sung, Y.F. Sung, M. Suzuki, M. Tan, S.C. Tang, T. Tatlisumak, V. Thijs, M. Tiainen, C.H. Tsai, C.K. Tsai, C.L. Tsai, H.T. Tsai, L.K. Tsai, C.H. Tseng, L.T. Tseng, J. Tsoleridis, H. Tu, H.T-H. Tu, W. Vallat, J. Virta, W.C. Wang, Y.T. Wang, M. Waters, L. Weir, T. Wijeratne, C. Williams, W. Wilson, A.A. Wong, K. Wong, T.Y. Wu, Y.H. Wu, B. Yan, F.C. Yang, Y.W. Yang, N. Yassi, H.L. Yeh, J.H. Yeh, S.J. Yeh, C.H. Yen, D. Young, C.L. Ysai, W.W. Zhang, H. Zhao, L. Zhao, Katharina Althaus-Knaurer, Jörg Berrouschot, Erich Bluhmki, Paolo Bovi, Gilles Chatellier, Lynda Cove, Stephen Davis, A. Dixit, Geoffrey Donnan, Christina Ehrenkrona, Christoph Eschenfelder, Marc Fatar, Juan Francisco Arenillas, Franz Gruber, Lalit Kala, Peter Kapeller, Markku Kaste, Christof Kessler, Martin Köhrmann, Rico Laage, Kennedy R. Lees, Alain Luna Rodriguez, Jean-Louis Mas, Robert Mikulik, Carlos Molina, Girish Muddegowda, Keith Muir, Kurt Niederkorn, Xavier Nuñez, Peter Schellinger, Joaquin Serena, Jan Sobesky, Thorsten Steiner, Ann-Sofie Svenson, Rüdiger von Kummer, Joanna Wardlaw, Rebecca A. Betensky, Gregoire Boulouis, Raphael A. Carandang, William A. Copen, Pedro Cougo, Shawna Cutting, Kendra Drake, Andria L. Ford, John Hallenbeck, Gordon J. Harris, Robert Hoesch, Amie Hsia, Carlos Kase, Lawrence Latour, Michael H. Lev, Alona Muzikansky, Nandakumar Nagaraja, Lee H. Schwamm, Eric Searls, Shlee S. Song, Sidney Starkman, Albert J. Yoo, Ramin Zand, Universitaetsklinikum Hamburg-Eppendorf = University Medical Center Hamburg-Eppendorf [Hamburg] (UKE), Hospices Civils de Lyon (HCL), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon, Monash University [Melbourne], National Cerebral and Cardiovascular Center (NCCC - OSAKA), Osaka University [Osaka], University of Heidelberg, Medical Faculty, Massachusetts General Hospital [Boston], University of Melbourne, Charité - UniversitätsMedizin = Charité - University Hospital [Berlin], Royal Adelaide Hospital [Adelaide Australia], National Institute of Neurological Disorders and Stroke [Bethesda] (NINDS), National Institutes of Health [Bethesda] (NIH), University Hospitals Leuven [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Flanders Make [Leuven], Flanders Make, University of Newcastle [Australia] (UoN), Troubles cognitifs dégénératifs et vasculaires - U 1171 (TCDV), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Vall d'Hebron University Hospital [Barcelona], University of Glasgow, Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-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)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hospices Civils de Lyon (HCL), Girona Biomedical Research Institute [Girona, Spain] (IDIBGI), Ruhr-Universität Bochum [Bochum], Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Aarhus University Hospital, Cedars-Sinai Medical Center, Florey Institute of Neuroscience and Mental Health [Melbourne, Victoria, Australia], Austin Health, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], China Medical University Hospital [Taichung], Karolinska Institutet [Stockholm], The Walter and Eliza Hall Institute of Medical Research (WEHI), University of Texas at Austin [Austin], Collaborators Evaluation of unknown Onset Stroke thrombolysis trials (EOS) investigators: Boris Raul Acosta, Karen Aegidius, Christian Albiker, Anna Alegiani, Miriam Almendrote, Angelika Alonso, Katharina Althaus, Pierre Amarenco, Hemasse Amiri, Bettina Anders, Adriana Aniculaesei, Jason Appleton, Juan Arenillas, Christina Back, Christian Bähr, Jürgen Bardutzky, Flore Baronnet-Chauvet, Rouven Bathe-Peters, Anna Bayer-Karpinska, Juan L Becerra, Christoph Beck, Olga Belchí Guillamon, Amandine Benoit, Nadia Berhoune, Daniela Bindila, Julia Birchenall, Karine Blanc-Lasserre, Miguel Blanco Gonzales, Tobias Bobinger, Ulf Bodechtel, Eric Bodiguel, Urszula Bojaryn, Louise Bonnet, Benjamin Bouamra, Paul Bourgeois, Florent Boutitie, Lorenz Breuer, Ludovic Breynaert, David Broughton, Raf Brouns, Sébastian Brugirard, Bart Bruneel, Florian Buggle, Serkan Cakmak, Ana Calleja, David Calvet, David Carrera, Hsin-Chieh Chen, Bastian Cheng, Bharath Cheripelli, Tae-Hee Cho, Chi-Un Choe, Lillian Choy, Hanne Christensen, Mareva Ciatipis, Geoffrey Cloud, Julien Cogez, Elisa Cortijo, Sophie Crozier, Dorte Damgaard, Krishna Dani, Beatrijs De Coene, Isabel De Hollander, Jacques De Keyser, Nina De Klippel, Charlotte De Maeseneire, Ann De Smedt, Maria Del Mar Castellanos Rodrigo, Sandrine Deltour, Jelle Demeestere, Laurent Derex, Philippe Desfontaines, Ralf Dittrich, Anand Dixit, Laurens Dobbels, Valérie Domigo, Laura Dorado, Charlotte Druart, Kristina Hougaard Dupont, Anne Dusart, Rainer Dziewas, Martin Ebinger, Matthias Ebner, Myriam Edjali-Goujon, Philipp Eisele, Salwa El Tawil, Ahmed Elhfnawy, Matthias Endres, Ana Etexberria, Nicholas Evans, Simon Fandler, Franz Fazekas, Sandra Felix, Jochen B Fiebach, Jens Fiehler, Alexandra Filipov, Katharina Filipski, Robert Fleischmann, Christian Foerch, Ian Ford, Alexandra Gaenslen, Ivana Galinovic, Elena Meseguer Gancedo, Ramanan Ganeshan, Carlos García Esperón, Alicia Garrido, Thomas Gattringer, Olivia Geraghty, Rohat Geran, Christian Gerloff, Stefan Gerner, Sylvie Godon-Hardy, Jos Göhler, Amir Golsari, Meritxell Gomis, David Gorriz, Verena Gramse, Laia Grau, Martin Griebe, Cristina Guerrero, Damla Guerzoglu, Sophie Guettier, Vincent Guiraud, Christoph Gumbinger, Ignaz Gunreben, Florian Haertig, Christian Hametner, Bernard Hanseeuw, Andreas Hansen, Jakob Hansen, Thomas Harbo, Andreas Harloff, Peter Harmel, Karl Georg Häusler, Florian Heinen, Valentin Held, Simon Hellwig, Dimitri Hemelsoet, Michael Hennerici, Juliane Herm, Sylvia Hermans, María Hernández, Jose Hervas Vicente, Niels Hjort, Cristina Hobeanu, Carsten Hobohm, Elmar Höfner, Katharina Hohenbichler, Marc Hommel, Julia Hoppe, Eva Hornberger, Carolin Hoyer, Xuya Huang, Nils Ipsen, Irina Isern, Lourdes Ispierto, Helle Iversen, Lise Jeppesen, Marta Jimenez, Jan Jungehülsing, Eric Jüttler, Dheeraj Kalladka, Bernd Kallmünzer, Arindam Kar, Lars Kellert, André Kemmling, Tobias Kessler, Usman Khan, Matthias Klein, Christoph Kleinschnitz, Matti Klockziem, Michael Knops, Luzie Koehler, Martin Koehrmann, Heinz Kohlfürst, Rainer Kollmar, Peter Kraft, Thomas Krause, Bo Kristensen, Jan M Kröber, Natalia Kurka, Alexandre Ladoux, Patrice Laloux, Catherine Lamy, Emmanuelle Landrault, Arne Lauer, Claire Lebely, Jonathan Leempoel, Kennedy Lees, Anne Leger, Laurence Legrand, Robin Lemmens, Lin Li, Anna-Mareike Löbbe, Frederic London, Elena Lopez-Cancio, Matthias Lorenz, Stephen Louw, Caroline Lovelock, Manuel Lozano Sánchez, Giuseppe Lucente, Janos Lückl, Alain Luna, Kosmas Macha, Alexandre Machet, Daniel Mackenrodt, Dominik Madzar, Charles Majoie, Anika Männer, Vicky Maqueda, Jacob Marstrand, Alicia Martinez, Annika Marzina, Laura Mechthouff, Per Meden, Guy Meersman, Julia Meier, Charles Mellerio, Oliver Menn, Nadja Meyer, Dominik Michalski, Peter Michels, Lene Michelsen, Monica Millán Torne, Jens Minnerup, Boris Modrau, Sebastian Moeller, Anette Møller, Nathalie Morel, Fiona Moreton, Ludovic Morin, Thierry Moulin, Barry Moynihan, Anne K Mueller, Keith W Muir, Patricia Mulero, Sibu Mundiyanapurath, Johannes Mutzenbach, Simon Nagel, Oliver Naggara, Arumugam Nallasivan, Irene Navalpotro, Alexander H Nave, Paul Nederkoorn, Lars Neeb, Hermann Neugebauer, Tobias Neumann-Haefelin, Norbert Nighoghossian, Stefan Oberndorfer, Christian Opherk, Lorenz Oppel, Catherine Oppenheim, Johannes Orthgieß, Leif Ostergaard, Perrine Paindeville, Ernest Palomeras, Verena Panitz, Bhavni Patel, Andre Peeters, Dirk Peeters, Anna Pellisé, Johann Pelz, Anthony Pereira, Natalia Pérez de la Ossa, Richard Perry, Salvador Petraza, Stéphane Peysson, Waltraud Pfeilschifter, Alexander Pichler, Alexandra Pierskalla, Hans-Werner Pledl, Sven Poli, Katrin Pomrehn, Marika Poulsen, Luis Prats, Silvia Presas, Elisabeth Prohaska, Volker Puetz, Josep Puig, Josep Puig Alcántara, Jan Purrucker, Veronique Quenardelle, Sankaranarayanan Ramachandran, Soulliard Raphaelle, Nicolas Raposo, Tilman Reiff, Michel Remmers, Pauline Renou, Martin Ribitsch, Hardy Richter, Peter Ringleb, Martin Ritter, Thomas Ritzenthaler, Gilles Rodier, Christine Rodriguez-Regent, Manuel Rodríguez-Yáñez, Maria Roennefarth, Christine Roffe, Sverre Rosenbaum, Charlotte Rosso, Joachim Röther, Michal Rozanski, Noelia Ruiz de Morales, Francesca Russo, Matthieu Rutgers, Sharmilla Sagnier, Yves Samson, Josep Sánchez, Tamara Sauer, Jan H Schäfer, Simon Schieber, Josef Schill, Dennis Schlak, Ludwig Schlemm, Sein Schmidt, Wouter Schonewille, Julian Schröder, Andreas Schulz, Johannes Schurig, Sönke Schwarting, Alexander Schwarz, Christopher Schwarzbach, Matthias Seidel, Alexander Seiler, Jochen Sembill, Joaquin Serena Leal, Ashit Shetty, Igor Sibon, Claus Z Simonsen, Oliver Singer, Aravinth Sivagnanaratham, Ide Smets, Craig Smith, Peter Soors, Nikola Sprigg, Maximilian Spruegel, David Stark, Susanne Steinert, Sebastian Stösser, Markus Stuermlinger, Bart Swinnen, Ruben Tamazyan, Jose Tembl, Mikel Terceno Izaga, Vincent Thijs, Götz Thomalla, Emmanuel Touze, Thomas Truelsen, Guillaume Turc, Gaetane Turine, Serdar Tütüncü, Pippa Tyrell, Xavier Ustrell, Wilfried Vadot, Anne-Evelyne Vallet, Pauline Vallet, Lucie van den Berg, Sophie van den Berg, Cecile van Eendenburg, Robbert-Jan Van Hooff, Isabelle van Sloten, Peter Vanacker, Evelien Vancaester, Patrick Vanderdonckt, Yves Vandermeeren, Frederik Vanhee, Roland Veltkamp, Karsten Vestergaard, Alain Viguier, Dolores Vilas, Kersten Villringer, Dieke Voget, Jörg von Schrader, Paul von Weitzel, Elisabeth Warburton, Claudia Weber, Jörg Weber, Karl Wegscheider, Mirko Wegscheider, Christian Weimar, Karin Weinstich, Christopher Weise, Gesa Weise, Chris Willems, Klemens Winder, Matthias Wittayer, Marc Wolf, Martin Wolf, Valerie Wolff, Christian Wollboldt, Frank Wollenweber, Anke Wouters, Bertrand Yalo, Marion Yger, Nadia Younan, Laetita Yperzeele, Vesna Zegarac, Pia Zeiner, Ulf Ziemann, Thomas Zonneveld, Mathieu Zuber, Tsugio Akutsu, Junya Aoki, Junya Aoki, Shuji Arakawa, Ryosuke Doijiri, Yusuke Egashira, Yukiko Enomoto, Mayumi Fukuda-Doi, Eisuke Furui, Konosuke Furuta, Seiji Gotoh, Toshimitsu Hamasaki, Yasuhiro Hasegawa, Teryuki Hirano, Kazunari Homma, Masahiko Ichijyo, Toshihiro Ide, Shuichi Igarashi, Yasuyuki Iguchi, Masafumi Ihara, Hajime Ikenouchi, Manabu Inoue, Tsuyoshi Inoue, Ryo Itabashi, Yasuhiro Ito, Toru Iwama, Kenji Kamiyama, Shoko Kamiyoshi, Haruka Kanai, Yasuhisa Kanematsu, Takao Kanzawa, Kazumi Kimura, Jiro Kitayama, Takanari Kitazono, Masatoshi Koga, Rei Kondo, Kohsuke Kudo, Masayoshi Kusumi, Ken Kuwahara, Shoji Matsumoto, Hideki Matsuoka, Ban Mihara, Kazuo Minematsu, Ken Miura, Kaori Miwa, Naomi Morita, Wataru Mouri, Kayo Murata, Yoshinari Nagakane, Taizen Nakase, Hiromi Ohara, Nobuyuki Ohara, Hideyuki Ohnishi, Hajime Ohta, Masafumi Ohtaki, Ryo Ohtani, Toshiho Ohtsuki, Hideo Ohyama, Takashi Okada, Yasushi Okada, Masato Osaki, Nobuyuki Sakai, Yoshiki Sanbongi, Naoshi Sasaki, Makoto Sasaki, Shoichiro Sato, Kenta Seki, Wataru Shimizu, Yoshiaki Shiokawa, Takashi Sozu, Junichiro Suzuki, Rieko Suzuki, Yasushi Takagi, Shunya Takizawa, Norio Tanahashi, Eijiro Tanaka, Ryota Tanaka, Yohei Tateishi, Tomoaki Terada, Tadashi Terasaki, Kenichi Todo, Azusa Tokunaga, Kazunori Toyoda, Akira Tsujino, Toshihiro Ueda, Yoshikazu Uesaka, Mihoko Uotani, Takao Urabe, Masao Watanabe, Yoshiki Yagita, Yusuke Yakushiji, Haruko Yamamoto, Keizo Yasui, Toshiro Yonehara, Sohei Yoshimura, Shinichi Yoshimura, K Aarnio, F Alemseged, C Anderson, T Ang, M L Archer, J Attia, P Bailey, A Balabanski, A Barber, P A Barber, J Bernhardt, A Bivard, D Blacker, C F Bladin, A Brodtmann, D Cadilhac, B C V Campbell, L Carey, S Celestino, L Chan, W H Chang, A ChangI, C H Chen, C-I Chen, H F Chen, T C Chen, W H Chen, Y Y Chen, C A Cheng, E Cheong, Y W Chiou, P M Choi, H J Chu, C S Chuang, T C Chung, L Churilov, B Clissold, A Connelly, S Coote, B Coulton, E Cowley, J Cranefield, S Curtze, C D'Este, S M Davis, S Day, P M Desmond, H M Dewey, C Ding, G A Donnan, R Drew, S Eirola, D Field, T Frost, C Garcia-Esperon, K George, R Gerraty, R Grimley, Y C Guo, G Hankey, J Harvey, S C Ho, K Hogan, D Howells, P M Hsiao, C H Hsu, C T Hsu, C-S Hsu, J P Hsu, Y D Hsu, Y T Hsu, C J Hu, C C Huang, H Y Huang, M Y Huang, S C Huang, W S Huang, D Jackson, J S Jeng, S K Jiang, L Kaauwai, O Kasari, J King, T J Kleinig, M Koivu, J Kolbe, M Krause, C W Kuan, W L Kung, C Kyndt, C L Lau, A Lee, C Y Lee, J T Lee, Y Lee, Y C Lee, C Levi, C R Levi, L M Lien, J C Lim, C C Lin, C H Lin, C M Lin, D Lin, C H Liu, J Liu, Y C Lo, P S Loh, E Low, C H Lu, C J Lu, M K Lu, J Ly, H Ma, L Macaulay, R Macdonnell, E Mackey, M Macleod, J Mahadevan, V Maxwell, R McCoy, A McDonald, S McModie, A Meretoja, S Mishra, P J Mitchell, F Miteff, A Moore, C Muller, F Ng, F C Ng, J-L Ng, W O'Brian, V O'Collins, T J Oxley, M W Parsons, S Patel, G S Peng, L Pesavento, T Phan, E Rodrigues, Z Ross, A Sabet, M Sallaberger, P Salvaris, D Shah, G Sharma, G Sibolt, M Simpson, S Singhal, B Snow, N Spratt, R Stark, J Sturm, M C Sun, Y Sun, P S Sung, Y F Sung, M Suzuki, M Tan, S C Tang, T Tatlisumak, V Thijs, M Tiainen, C H Tsai, C K Tsai, C L Tsai, H T Tsai, L K Tsai, C H Tseng, L T Tseng, J Tsoleridis, H Tu, H T-H Tu, W Vallat, J Virta, W C Wang, Y T Wang, M Waters, L Weir, T Wijeratne, C Williams, W Wilson, A A Wong, K Wong, T Y Wu, Y H Wu, B Yan, F C Yang, Y W Yang, N Yassi, H L Yeh, J H Yeh, S J Yeh, C H Yen, D Young, C L Ysai, W W Zhang, H Zhao, L Zhao, Katharina Althaus-Knaurer, Martin Bendszus, Jörg Berrouschot, Erich Bluhmki, Paolo Bovi, Gilles Chatellier, Lynda Cove, Stephen Davis, A Dixit, Geoffrey Donnan, Rainer Dziewas, Christina Ehrenkrona, Christoph Eschenfelder, Marc Fatar, Juan Francisco Arenillas, Franz Gruber, Werner Hacke, Lalit Kala, Peter Kapeller, Markku Kaste, Christof Kessler, Martin Köhrmann, Rico Laage, Kennedy R Lees, Didier Leys, Alain Luna Rodriguez, Jean-Louis Mas, Robert Mikulik, Carlos Molina, Girish Muddegowda, Keith Muir, Kurt Niederkorn, Xavier Nuñez, Catherine Oppenheim, Sven Poli, Peter Ringleb, Peter Schellinger, Stefan Schwab, Joaquin Serena, Jan Sobesky, Thorsten Steiner, Ann-Sofie Svenson, Danilo Toni, Roland Veltkamp, Rüdiger von Kummer, Nils Wahlgren, Joanna Wardlaw, Rebecca A Betensky, Gregoire Boulouis, Raphael A Carandang, William A Copen, Pedro Cougo, Shawna Cutting, Kendra Drake, Andria L Ford, John Hallenbeck, Gordon J Harris, Robert Hoesch, Amie Hsia, Carlos Kase, Lawrence Latour, Arne Lauer, Michael H Lev, Alona Muzikansky, Nandakumar Nagaraja, Lee H Schwamm, Eric Searls, Shlee S Song, Sidney Starkman, Steven Warach, Ona Wu, Albert J Yoo, Ramin Zand, University of Newcastle [Callaghan, Australia] (UoN), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Troubles cognitifs dégénératifs et vasculaires - U 1171 - EA 1046 (TCDV), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille, Droit et Santé-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), CarMeN, laboratoire, Yperzeele, Laetitia, Evaluation of Unknown Onset Stroke Thrombolysis trials (EOS) investigators, UCL - SSS/IONS - Institute of NeuroScience, UCL - (MGD) Service de neurologie, Supporting clinical sciences, UZB Other, Physical Medicine and Rehabilitation, Clinical sciences, Neuroprotection & Neuromodulation, Radiology and Nuclear Medicine, ANS - Neurovascular Disorders, Neurology, ACS - Atherosclerosis & ischemic syndromes, Graduate School, Center of Experimental and Molecular Medicine, ACS - Pulmonary hypertension & thrombosis, and ACS - Microcirculation

Subjects
medicine.medical_treatment, [SDV]Life Sciences [q-bio], Ischemic Stroke/*diagnostic imaging/*drug therapy, Tomography, X-Ray Computed/methods, Fibrinolytic Agents/adverse effects/*therapeutic use, 030204 cardiovascular system & hematology, Ischemic Stroke/diagnostic imaging, surgery, 0302 clinical medicine, Modified Rankin Scale, 030212 general & internal medicine, 10. No inequality, Infusions, Intravenous, Stroke, Tomography, Time-to-Treatment, General Medicine, Thrombolysis, X-Ray Computed/methods, Tissue Plasminogen Activator/adverse effects, 3. Good health, [SDV] Life Sciences [q-bio], Diffusion Magnetic Resonance Imaging/methods, Treatment Outcome, Meta-analysis, Tissue Plasminogen Activator, Intravenous, medicine.medical_specialty, Infusions, Intravenous thrombolysis, Neuroimaging, Neuroscience(all), Placebo, Tissue Plasminogen Activator/adverse effects/*therapeutic use, 03 medical and health sciences, Fibrinolytic Agents, Internal medicine, medicine, Humans, ddc:610, Ischemic Stroke, business.industry, neurology, Fibrinolytic Agents/adverse effects, Odds ratio, Recovery of Function, medicine.disease, Clinical research, Diffusion Magnetic Resonance Imaging, Human medicine, business, Tomography, X-Ray Computed, Fibrinolytic agent
Abstract

International audience; BACKGROUND: Patients who have had a stroke with unknown time of onset have been previously excluded from thrombolysis. We aimed to establish whether intravenous alteplase is safe and effective in such patients when salvageable tissue has been identified with imaging biomarkers. METHODS: We did a systematic review and meta-analysis of individual patient data for trials published before Sept 21, 2020. Randomised trials of intravenous alteplase versus standard of care or placebo in adults with stroke with unknown time of onset with perfusion-diffusion MRI, perfusion CT, or MRI with diffusion weighted imaging-fluid attenuated inversion recovery (DWI-FLAIR) mismatch were eligible. The primary outcome was favourable functional outcome (score of 0-1 on the modified Rankin Scale [mRS]) at 90 days indicating no disability using an unconditional mixed-effect logistic-regression model fitted to estimate the treatment effect. Secondary outcomes were mRS shift towards a better functional outcome and independent outcome (mRS 0-2) at 90 days. Safety outcomes included death, severe disability or death (mRS score 4-6), and symptomatic intracranial haemorrhage. This study is registered with PROSPERO, CRD42020166903. FINDINGS: Of 249 identified abstracts, four trials met our eligibility criteria for inclusion: WAKE-UP, EXTEND, THAWS, and ECASS-4. The four trials provided individual patient data for 843 individuals, of whom 429 (51%) were assigned to alteplase and 414 (49%) to placebo or standard care. A favourable outcome occurred in 199 (47%) of 420 patients with alteplase and in 160 (39%) of 409 patients among controls (adjusted odds ratio [OR] 1·49 [95% CI 1·10-2·03]; p=0·011), with low heterogeneity across studies (I(2)=27%). Alteplase was associated with a significant shift towards better functional outcome (adjusted common OR 1·38 [95% CI 1·05-1·80]; p=0·019), and a higher odds of independent outcome (adjusted OR 1·50 [1·06-2·12]; p=0·022). In the alteplase group, 90 (21%) patients were severely disabled or died (mRS score 4-6), compared with 102 (25%) patients in the control group (adjusted OR 0·76 [0·52-1·11]; p=0·15). 27 (6%) patients died in the alteplase group and 14 (3%) patients died among controls (adjusted OR 2·06 [1·03-4·09]; p=0·040). The prevalence of symptomatic intracranial haemorrhage was higher in the alteplase group than among controls (11 [3%] vs two [\textless1%], adjusted OR 5·58 [1·22-25·50]; p=0·024). INTERPRETATION: In patients who have had a stroke with unknown time of onset with a DWI-FLAIR or perfusion mismatch, intravenous alteplase resulted in better functional outcome at 90 days than placebo or standard care. A net benefit was observed for all functional outcomes despite an increased risk of symptomatic intracranial haemorrhage. Although there were more deaths with alteplase than placebo, there were fewer cases of severe disability or death. FUNDING: None.

Published
2020
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20. Dissipative elastic metamaterials for broadband wave mitigation at subwavelength scale

Author

Y.Y. Chen, C.T. Sun, Gengkai Hu, Guoliang Huang, J.K. Chen, and Miles V. Barnhart

Subjects
Materials science, business.industry, Attenuation, Physics::Optics, Metamaterial, 02 engineering and technology, 021001 nanoscience & nanotechnology, Viscoelasticity, Resonator, 020303 mechanical engineering & transports, Optics, Effective mass (solid-state physics), 0203 mechanical engineering, Broadband, Ceramics and Composites, Dissipative system, 0210 nano-technology, business, Blast wave, Civil and Structural Engineering
Abstract

In this paper, an elastic metamaterial with multiple dissipative resonators is presented for broadband wave mitigation by properly utilizing interactions from resonant motions and viscoelastic effects of the constitutive material. The working mechanism of the metamaterial to suppress broadband waves is clearly revealed in a dissipative mass-in-mass lattice system through both negative effective mass density and effective metadamping coefficient. Based on the novel metadamping mechanism, a microstructure design of the dissipative metamaterial made of multi-layered viscoelastic continuum media is first proposed for efficient attenuation of a transient blast wave. It is found that the extremely broadband waves can be almost completely mitigated with metamaterials at subwavelength scale. The results of the study could be used in developing new multifunctional composite materials to suppress the shock or blast waves which may cause severe local damage to engineering structures.

Published
2016
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21. Bending, buckling and free vibration of an axially loaded timoshenko beam with transition parameter: Direction of axial force

Author

Xu-Feng Wang, Tan You, Xiaotao Li, Y.Y. Chen, and H.J. Cao

Subjects
Timoshenko beam theory, Materials science, Mechanical Engineering, 02 engineering and technology, Bending, Mechanics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Vibration, 020303 mechanical engineering & transports, 0203 mechanical engineering, Buckling, Mechanics of Materials, Physics::Accelerator Physics, General Materials Science, Boundary value problem, Deformation (engineering), 0210 nano-technology, Axial symmetry, Beam (structure), Civil and Structural Engineering
Abstract

This paper aims to investigate the bending, buckling and free vibration problems of an axially loaded Timoshenko beam in a systematic manner. A recently-developed unified model is adopted, where a transition parameter characterizing the direction of the axial force during the deformation is introduced. For beams with various boundary conditions, closed-form expressions of deflections and critical buckling loadings are obtained in an analytical fashion and frequency equations are derived. It is highlighted that the inherent relations of the buckling loadings for the Timoshenko and Euler-Bernoulli beams are explicitly extracted. Numerical calculations are carried out to check the validity of the present solutions and to quantify the effects of the transition parameter. Significant effects of the transition parameter are revealed on the bending, buckling and free vibration of the axially loaded beam. The present analysis is of significance to axially-loaded beam-like mechanical system, especially for determination of the direction of axially force.

Published
2020
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22. Extending thrombolysis to 4·5–9 h and wake-up stroke using perfusion imaging. a systematic review and meta-analysis of individual patient data

Author

Bruce C V Campbell, Henry Ma, Peter A Ringleb, Mark W Parsons, Leonid Churilov, Martin Bendszus, Christopher R Levi, Chung Hsu, Timothy J Kleinig, Marc Fatar, Didier Leys, Carlos Molina, Tissa Wijeratne, Sami Curtze, Helen M Dewey, P Alan Barber, Kenneth S Butcher, Deidre A De Silva, Christopher F Bladin, Nawaf Yassi, Johannes A R Pfaff, Gagan Sharma, Andrew Bivard, Patricia M Desmond, Stefan Schwab, Peter D Schellinger, Bernard Yan, Peter J Mitchell, Joaquín Serena, Danilo Toni, Vincent Thijs, Werner Hacke, Stephen M Davis, Geoffrey A Donnan, Geoffrey A. Donnan, Stephen M. Davis, Bruce C.V. Campbell, Mark W. Parsons, Peter J. Mitchell, Patricia M. Desmond, Thomas Oxley, Teddy Y. Wu, Darshan Shah, Henry Zhao, Edrich Rodrigues, Patrick Salvaris, Fana Alemseged, Felix Ng, Cameron Williams, Jo-Lyn Ng, Hans T-H. Tu, Amy McDonald, David Jackson, Jessica Tsoleridis, Rachael McCoy, Lauren Pesavento, Louise Weir, Timothy J. Kleinig, S. Patel, J. Harvey, J. Mahadevan, E. Cheong, Anna Balabanski, Michael Waters, Roy Drew, Jennifer Cranefield, Elizabeth Mackey, Sherisse Celestino, Essie Low, Helen M. Dewey, Christopher F. Bladin, Poh Sien Loh, Philip M. Choi, Skye Coote, Tanya Frost, K. Hogan, C. Ding, S. McModie, W.W. Zhang, Christopher Kyndt, A. Moore, Z. Ross, J. Liu, Ferdinand Miteff, Christopher R. Levi, Timothy Ang, Neil Spratt, Carlos Garcia-Esperon, Lara Kaauwai, Thanh G. Phan, John Ly, Shaloo Singhal, Benjamin Clissold, Kitty Wong, Martin Krause, Susan Day, Jonathan Sturm, Bill O'Brian, Rohan Grimley, Marion Simpson, Matthew Lee-Archer, Amy Brodtmann, Bronwyn Coulton, Dennis Young, Andrew A. Wong, Claire Muller, Deborah K. Field, W. Vallat, Vanessa Maxwell, Peter Bailey, Arman Sabet, Sachin Mishra, Meng Tan, K. George, P. Alan Barber, L. Zhao, Atte Meretoja, Turgut Tatlisumak, G. Sibolt, M. Tiainen, M. Koivu, K. Aarnio, J. Virta, O. Kasari, S. Eirola, M.C. Sun, T.C. Chen, C.S. Chuang, Y.Y. Chen, C.M. Lin, S.C. Ho, P.M. Hsiao, C.H. Tsai, W.S. Huang, Y.W. Yang, H.Y. Huang, W.C. Wang, C.H. Liu, M.K. Lu, C.H. Lu, W.L. Kung, S.K. Jiang, Y.H. Wu, S.C. Huang, C.H. Tseng, L.T. Tseng, Y.C. Guo, D. Lin, C.T. Hsu, C.W. Kuan, J.P. Hsu, H.T. Tsai, M. Suzuki, Y. Sun, H.F. Chen, C.J. Lu, C.H. Lin, C.C. Huang, H.J. Chu, C.Y. Lee, W.H. Chang, Y.C. Lo, Y.T. Hsu, C.H. Chen, P.S. Sung, C.L. Ysai, J.S. Jeng, S.C. Tang, L.K. Tsai, S.J. Yeh, Y.C. Lee, Y.T. Wang, T.C. Chung, C.J. Hu, L. Chan, Y.W. Chiou, L.M. Lien, H.L. Yeh, J.H. Yeh, W.H. Chen, C.L. Lau, A. Chang, I.Y. Lee, M.Y. Huang, J.T. Lee, G.S. Peng, J.C. Lim, Y.D. Hsu, C.C. Lin, C.A. Cheng, C.H. Yen, F.C. Yang, C.H. Hsu, Y.F. Sung, C.K. Tsai, C.L. Tsai, A. Lee, Graeme Hankey, David Blacker, Richard Gerraty, C-I. Chen, C-S. Hsu, Elise Cowley, Michele Sallaberger, Barry Snow, John Kolbe, Richard Stark, John King, Richard Macdonnell, John Attia, Catherine D'Este, Julie Bernhardt, Leeanne Carey, Dominique Cadilhac, Craig Anderson, David Howells, A. Barber, Alan Connelly, Malcolm Macleod, Victoria O'Collins, W. Wilson, L. Macaulay, Erich Bluhmki, Christoph Eschenfelder, Peter Ringleb, Peter Schellinger, Nils Wahlgren, Joanna Wardlaw, Catherine Oppenheim, Kennedy R. Lees, Markku Kaste, Rüdiger von Kummer, Gilles Chatellier, Rico Laage, Xavier Nuñez, Christina Ehrenkrona, Ann-Sofie Svenson, Lynda Cove, Kurt Niederkorn, Franz Gruber, Peter Kapeller, Robert Mikulik, Jean-Louis Mas, Jörg Berrouschot, Jan Sobesky, Martin Köhrmann, Thorsten Steiner, Christof Kessler, Rainer Dziewas, Sven Poli, Katharina Althaus-Knaurer, Paolo Bovi, Alain L. Rodriguez, Juan F. Arenillas, Keith Muir, Roland Veltkamp, Anand Dixit, Girish Muddegowda, Lalit Kala, Deidre A. De Silva, Kenneth S. Butcher, G. Byrnes, Andre Peeters, J.B. Chalk, John N. Fink, Thomas E. Kimber, David Schultz, Peter J. Hand, Judith Frayne, Brian M. Tress, John McNeil, R. Burns, C. Johnston, and M. Williams

Subjects
medicine.medical_specialty, acute ischemic stroke, thrombolysis, Perfusion Imaging, medicine.medical_treatment, Perfusion scanning, 030204 cardiovascular system & hematology, Placebo, Brain Ischemia, Time-to-Treatment, 03 medical and health sciences, 0302 clinical medicine, Fibrinolytic Agents, Modified Rankin Scale, Internal medicine, medicine, Humans, Thrombolytic Therapy, rt-pa, 030212 general & internal medicine, Stroke, Cerebral Hemorrhage, business.industry, General Medicine, Odds ratio, Thrombolysis, medicine.disease, 3. Good health, meta-analysis, Diffusion Magnetic Resonance Imaging, Treatment Outcome, Tissue Plasminogen Activator, Meta-analysis, acute stroke therapy, Tomography, X-Ray Computed, business, Fibrinolytic agent
Abstract

Stroke thrombolysis with alteplase is currently recommended 0-4·5 h after stroke onset. We aimed to determine whether perfusion imaging can identify patients with salvageable brain tissue with symptoms 4·5 h or more from stroke onset or with symptoms on waking who might benefit from thrombolysis.In this systematic review and meta-analysis of individual patient data, we searched PubMed for randomised trials published in English between Jan 1, 2006, and March 1, 2019. We also reviewed the reference list of a previous systematic review of thrombolysis and searched ClinicalTrials.gov for interventional studies of ischaemic stroke. Studies of alteplase versus placebo in patients (aged ≥18 years) with ischaemic stroke treated more than 4·5 h after onset, or with wake-up stroke, who were imaged with perfusion-diffusion MRI or CT perfusion were eligible for inclusion. The primary outcome was excellent functional outcome (modified Rankin Scale [mRS] score 0-1) at 3 months, adjusted for baseline age and clinical severity. Safety outcomes were death and symptomatic intracerebral haemorrhage. We calculated odds ratios, adjusted for baseline age and National Institutes of Health Stroke Scale score, using mixed-effects logistic regression models. This study is registered with PROSPERO, number CRD42019128036.We identified three trials that met eligibility criteria: EXTEND, ECASS4-EXTEND, and EPITHET. Of the 414 patients included in the three trials, 213 (51%) were assigned to receive alteplase and 201 (49%) were assigned to receive placebo. Overall, 211 patients in the alteplase group and 199 patients in the placebo group had mRS assessment data at 3 months and thus were included in the analysis of the primary outcome. 76 (36%) of 211 patients in the alteplase group and 58 (29%) of 199 patients in the placebo group had achieved excellent functional outcome at 3 months (adjusted odds ratio [OR] 1·86, 95% CI 1·15-2·99, p=0·011). Symptomatic intracerebral haemorrhage was more common in the alteplase group than the placebo group (ten [5%] of 213 patients vs one [1%] of 201 patients in the placebo group; adjusted OR 9·7, 95% CI 1·23-76·55, p=0·031). 29 (14%) of 213 patients in the alteplase group and 18 (9%) of 201 patients in the placebo group died (adjusted OR 1·55, 0·81-2·96, p=0·66).Patients with ischaemic stroke 4·5-9 h from stroke onset or wake-up stroke with salvageable brain tissue who were treated with alteplase achieved better functional outcomes than did patients given placebo. The rate of symptomatic intracerebral haemorrhage was higher with alteplase, but this increase did not negate the overall net benefit of thrombolysis.None.

Published
2019

25. Experimental study on overlapped CHS K-joints with hidden seam unwelded

Author

R.Q. Zhang, G.N. Wang, X.Z. Zhao, Y. Chen, Y.Y. Chen, B.C. Tang, and L.X. Xu

Subjects
Materials science, business.industry, Fillet weld, Local failure, Failure mechanism, Welding, Structural engineering, Compression (physics), Span (engineering), Brace, law.invention, law, business, Joint (geology)
Abstract

Overlapped Circular-Hollow-Section K-joints are widely used in large span structures in China. In practice, the hidden toe of this type of joints is normally left unwelded due to the difficulty resulted from the fabrication sequence. It is thus necessary to investigate how the unwelded hidden seam may affect the behaviour of overlapped CHS K-joints. This paper reports seven static tests on uniplanar overlapped CHS K-joints with hidden seam unwelded under axial loading. Among these 7 specimens, parameters including the overlapped ratio, the brace-to-chord diameter ratio, the brace-to-chord thickness ratio, the brace inclination, the throat thickness of fillet welds, the unbalanced loading at the joint as well as the loading hierarchy reversal were varied to study their effect on the joint behaviour. In order to study the effect of the hidden seam on the behaviour of the connection, three additional specimens with the hidden seam welded were also tested for comparison purposes. Results of these tests show that the welding situation of the hidden seam has some effect on the stress distribution and failure mechanism, but the static ultimate capacity of the overlapped CHS K-joints is not affected significantly given that the through brace is under compression. When the brace-to-chord thickness ratio is smaller, the local failure is the main failure mechanism observed. Comparison of the joint capacities obtained from the tests with strength prediction from current design codes was presented.

Published
2017
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26. Comparison between a cast steel joint and a welded circular hollow section joint

Author

L.W. Tong, H.Z. Zheng, and Y.Y. Chen

Subjects
Chord (geometry), Materials science, business.industry, Truss, Welding, Structural engineering, Finite element method, law.invention, Stress (mechanics), law, Section (archaeology), business, Joint (geology), Strain gauge
Abstract

Experimental comparison was performed between a cast steel joint and a welded circular hollow section joint in tubular truss structures to investigate their behaviour and difference. The cast steel joint was 70 mm thick, whereas the welded circular hollow section joint was fabricated using 30 mm thickness steel plate and stiffeners was set inside the chord member at the joint. The two joints were experimented under the same testing condition. Strain gauges were arranged to measure stress distributions in the joints. Finite element analysis was carried out to get more information on the behaviour of the joints. The experimental and numerical results showed both joints had enough strength to bear design loads. This means welded circular hollow section joints are also alternative approach for large and complicated joints of space trusses, besides cast steel joints.

Published
2017
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27. PO-279 Interplay between Indoleamine 2,3-dioxigenase 1 and Notch1 in radiation response of cervical stem cancer cells

Author

H.L. Wang, Wen-Wei Chang, H.T. Shen, and Y.Y. Chen

Subjects
Cancer Research, biology, Chemistry, Cancer, biology.organism_classification, medicine.disease, Jurkat cells, Metastasis, HeLa, Oncology, Cancer stem cell, Radioresistance, Cancer cell, medicine, Cancer research, Clonogenic assay
Abstract

Introduction Cervical cancer is the fourth common cancer in female around the world. Cancer stem cells (CSCs) are responsible for the initiation, maintenance, drug resistance and metastasis of tumours and are considered as an effective therapeutic target. Indoleamine 2,3-dioxygenase 1 (IDO1) catalyses tryptophan metabolising to kynurenine and plays a role in immunosuppressive microenvironment within cancers. Notch1 expression participates in radioresistance of cancer cells. The purpose of this study is to explore the relationship between Notch1 and IDO1 expression in radiation response of cervical CSCs. Material and methods Cervical CSCs were enriched by tumorsphere cultivation from HeLa or SiHa cervical cancer cell lines. The expression of IDO1 and Notch1 was determined by western blot or real-time RT-PCR. The IDO1 activity in cell lysates was determined by measurement of kynurenine fluorescence converted from tryptophan. Radiation response of cervical cancer cells were determined by clonogenic assay. The binding of Notch intracellular domain (NICD) on IDO1 promoter was determined by chromatin immunoprecipitation (ChIP) assay. shRNA mediated RNA interference was used for knockdown of specific genes. Results and discussions We first found that the expression of IDO1, as well as NICD, was increased in cervical tumorspheres by western blot analysis. We also found that the IDO1 activity in total cell lysates was significantly increased in cervical tumorspheres than the parental cells. Using Jurkat T cells as a model, the growth rate of T cells was significantly decreased in conditional medium from tumorsphere cultivation when compared to those from parental adherent culture. In addition, IDO1 expression was suppressed in HeLa or SiHa cervical cancer cells with knockdown of Notch1. The binding of NICD on IDO1 promoter was inhibited by Notch1 inhibitor. The radiosensitivity of cervical cancer cells was increased by the treatment of IDO1 inhibitor but was decreased after treatment of kynurenine. Furthermore, the expression of NICD protein, as well as Notch1 or BMI1 mRNA, was decreased in cervical tumorspheres with IDO1 knockdown. We also observed that Inhibition of AhR or ARNT, the signalling molecules of kynurenine, suppressed CSC activity of cervical cancer cells. Conclusion Our data indicated that there is a reciprocal regulation mechanism of Notch1 and IDO1 expression in cervical CSCs. These results will provide new insights in the development of the combination of immunotherapy and radiotherapy in against cervical cancer.

Published
2018
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28. Progress in developing ITER and DEMO first wall technologies at SWIP

Author

P.H. Wang, Xuejun Liu, P. Huang, Quan Li, L.Z. Cai, J.B. Wang, J.M. Chen, Xuru Duan, X.B. Zhu, F.Y. Jin, Y.Y. Chen, Ming Xu, and Z.X. Wei

Subjects
Nuclear and High Energy Physics, Materials science, Nuclear engineering, chemistry.chemical_element, engineering.material, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, Cracking, Coating, chemistry, Heat flux, Martensite, visual_art, 0103 physical sciences, engineering, visual_art.visual_art_medium, Brazing, Tile, 010306 general physics, Material properties, Tin
Abstract

The first wall (FW) is key component for ITER and the Chinese DEMO—the China Fusion Engineering Test Reactor (CFETR). It faces burning plasma and has a high heat flux (HHF) surface load. Critical issues and key technologies for manufacturing the ITER and CFETR FW are discussed with regards to thermal fatigue performance, Be/CuCrZr and W/reduced activation ferritic/martensitic (RAFM) steel bonding, material properties and failure mechanisms. Design improvement of the hypervapotron cooling channel and the joint interface structure was done, which increases the thermal fatigue lifetime of the enhanced heat flux (EHF) ITER FW by more than one order of magnitude as indicated by thermo-mechanical analysis. Small mock-ups and full-size EHF FW fingers were manufactured by qualified technologies in sequence. An HHF test of the small mock-ups showed that Be tile size and defects at the Be/CuCrZr interface have a great effect on the fatigue lifetime. Manufacturing tests showed a thick oxygen-free Cu interlayer could provide a good solution for the interface cracking issue. An ITER EHF FW semi-prototype was manufactured with additional two full-size finger pairs that successfully survived the demanding HHF test at 4.7 and 5.9 MW m−2. Various manufacturing technologies for joining W/RAFM steel for the CFETR FW have been studied, including a TiN coating at the interface as a tritium permeation barrier. Hot iso-static pressed W/RAFM steel joints showed a higher bonding strength than brazing joints but varied a lot with the interlayer metals. Further studies are required to optimize the technologies.

Published
2019
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29. Sentinel Lymph Node Identification Rate After Neoadjuvant Chemotherapy for Breast Cancer Patients in an Asian Cancer Centre: a 16-year Experience

Author

S. Kwauk, C.F. Hung, T.J. Tsai, T.Y. Cheng, Y.Y. Chen, C.W. Lin, B.L. Yu, H.K. Wei, C.C. Lee, and C.M. Chen

Subjects
Oncology, Chemotherapy, medicine.medical_specialty, business.industry, medicine.medical_treatment, Sentinel lymph node, General Medicine, medicine.disease, Identification rate, Breast cancer, Internal medicine, Cancer centre, Medicine, Surgery, business
Published
2019
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30. Genetic diversity of the Chinese traditional herb Blumea balsamifera (Asteraceae) based on AFLP markers

Author

Wei Wang, J.B. Yu, Yu-Xin Pang, M. Zhu, Y.Y. Chen, Y. Yuan, and Ying-Bo Zhang

Subjects
Genetic Markers, Conservation genetics, Germplasm, Genetic diversity, UPGMA, Genetic Variation, General Medicine, Asteraceae, Biology, biology.organism_classification, Genetic distance, Genetic variation, Botany, Genetics, Humans, Amplified fragment length polymorphism, Blumea balsamifera, Amplified Fragment Length Polymorphism Analysis, Medicine, Chinese Traditional, Molecular Biology
Abstract

Blumea balsamifera is a commercially important medicinal herb in China and other parts of Asia. It is used to produce borneol. This plant grows in the wild, but resources have diminished greatly in recent years. We examined the genetic diversity of this species to help develop conservation strategies; 35 plants from five provinces were analyzed using AFLPs. Eight AFLP primer combinations generated 1367 fragments, giving a mean of 172 fragments per primer combination. Polymorphism in the germplasm analysis was found for 1360 (99.48%) of the fragments, of which 264 (19.27%) fragments were unique (accession specific) and 423 (25.33%) of the fragments were rare (present in less than 10% of the accessions). The polymorphic fragments were used to group the accessions in a UPGMA phenogram. Most grouping was geographical. In general, accessions coming from Guizhou and Guangxi showed higher diversities as these accessions were scattered in different groups. The genetic distance estimated by Jaccard similarity coefficient index showed low variability among genotypes (coefficient value ranged from 0.60 to 0.95). More attention should be given to the study and conservation of the biodiversity of this economically important genus.

Published
2014
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32. Efficient plant regeneration in three cultivars of Hami melon [Cucumis meloL. ssp.meloconvar.ameri(Pang.) Greb] via organogenesis

Author

W. Q. Zhai, L.Z. Liu, Periasamy Chitrampalam, B. Shi, W. M. Zhu, and Y.Y. Chen

Subjects
Murashige and Skoog medium, biology, Melon, Botany, Shoot, Genetics, Organogenesis, Cultivar, Horticulture, Hami melon, biology.organism_classification, Cucumis, Explant culture
Abstract

SummaryHami melon [Cucumis melo L. ssp. melo convar. ameri (Pang.) Greb] is reputed to be the ‘king of melons’, but commercial development of transgenic Hami melon cultivars is limited by low levels of plant regeneration and a high incidence of polyploid regenerants. Regeneration systems for three Hami melon varieties, namely ‘Jin Queen’, ‘Hongmibao’, and ‘Huangzhuixian’, were developed via organogenesis in tissue culture. Leaf explants ranging from 0.125 – 0.500× the full-size of each leaf were prepared in vitro from seedlings of different ages, then cultured on Murashige and Skoog (MS) medium containing various concentrations of 6-benzylaminopurine (BAP; 1.0 – 9.0 mg l–1) to determine optimal conditions for induction of adventitious shoots. Leaves from 8-d old seedlings were cut into four, approximately-equal segments. Plant regeneration was greatest on MS medium containing 3.0 mg l–1 BAP, with a shoot induction frequency of 90% for ‘Hongmibao’. For ‘Jin Queen’ and ‘Huangzhuixian’, the highest frequenci...

Published
2013
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34. Differentially expressed genes implicated in embryo abortion of mango identified by suppression subtractive hybridization

Author

H.R. Shu, F.W. Ma, J.H. He, and Y.Y. Chen

Subjects
Candidate gene, Plant Infertility, Biology, Abortion, Genes, Plant, Gene Expression Regulation, Plant, Genetics, Molecular Biology, reproductive and urinary physiology, Expressed Sequence Tags, Expressed sequence tag, Mangifera, Base Sequence, Contig, Reverse Transcriptase Polymerase Chain Reaction, cDNA library, Gene Expression Profiling, Nucleic Acid Hybridization, food and beverages, Molecular Sequence Annotation, Embryo, General Medicine, Differentially expressed genes, Suppression subtractive hybridization, Seeds, embryonic structures
Abstract

Embryo abortion in mango severely damages mango production worldwide. The mechanisms by which the mango embryos abort have long been an intriguing question. We used subtractive suppression hybridization to investigate the differentially expressed genes involved in this process. We generated 2 cDNA libraries from normal seed and aborted seed embryos of mango cultivar 'Jinhuang'. One thousand five hundred and seventy-two high-quality expressed sequence tags (ESTs) were obtained, with 1092 from the normal seed tester library and 480 from the aborted seed tester library. These ESTs were assembled into 783 unigenes, including 147 contigs and 636 singletons in contigs; 297 singletons in gene ontology (GO) indicated coverage of a broad range of GO categories. Seven candidate genes from different categories were selected for semi-quantitative PCR analysis, and their possible functions in embryo abortion are discussed. These data provide new insight into the genetic regulation of embryo abortion in mango and may aid in further identification of novel genes and their functions.

Published
2012
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35. Stress Characteristics Analysis of a Corrugated Web Composite Girder under Out-Plane Bending

Author

Zhangyu Wang, Lijie Tan, Q.Y. Wang, Y.Y. Chen, and R.J. Jiang

Subjects
Engineering, business.industry, General Engineering, Structural engineering, Bending, Welding, Flange, Finite element method, law.invention, Stress (mechanics), law, Girder, business, Beam (structure), Stress concentration
Abstract

The focus of this study is to analyse the stress distribution of corrugated web girder subjected to out-plane bending. Welded joining is considered in this study to connect the corrugated web and beam flange. As stress concentration is very critical for the prediction of fatigue life of the structure, this study provides preliminary results for further fatigue assessment of box-section girder bridge with such structural details. A finite element analysis based study has been conducted to trace the stress distribution along the corrugated web with varying thickness and cope hole details. The comparison with related simplified expression and typical stress concentration behaviours are outlined in this paper. Comments are given for the further consideration of presented stress characteristics in the fatigue design.

Published
2011
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36. Effect of annealing on field emission properties of nanodiamond coating

Author

Zhiyong Zhang, Lili Zhao, Y.Y. Chen, Jiangni Yun, Xuewen Wang, and Chunxue Zhai

Subjects
Materials science, Annealing (metallurgy), Diamond, engineering.material, Condensed Matter Physics, Detonation nanodiamond, Electronic, Optical and Magnetic Materials, Field electron emission, Electrophoretic deposition, symbols.namesake, Chemical engineering, Coating, engineering, symbols, Electrical and Electronic Engineering, Nanodiamond, Raman spectroscopy
Abstract

Field electron emission of detonation nanodiamond (ND) coated on a titanium substrate by electrophoretic deposition is investigated. It is found that thermal annealing can significantly improve the field emission properties of the ND layer, which can be mainly attributed to the formation of the TiC phase between diamond and Ti. The first-principles calculated results show that the formation of transition layers can lower the interface barrier and enhance the field electron emission of ND coating. Besides, the transformation of diamond to graphite after annealing has been revealed by Raman spectra. This transformation also benefits the electron emission enhancement.

Published
2011
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37. Calorimetric properties of C14 and C15 YMn2 and YMn2(H,D)6

Author

R Wierzbicki, Y.Y. Chen, H. T. Kuo, Ru-Shi Liu, C.B. Tsai, Ramazan Asmatulu, Ivan Baginskiy, C.C. Yang, L.N. Fomicheva, H.H. Wu, J.C. Ho, A.V. Tsvyashchenko, Stanislaw M. Filipek, and R. Sato

Subjects
Diffraction, Phase transition, Hydrogen, Renewable Energy, Sustainability and the Environment, Chemistry, Energy Engineering and Power Technology, Thermodynamics, chemistry.chemical_element, Calorimetry, Condensed Matter Physics, Magnetic susceptibility, Hydrogen storage, Fuel Technology, Electrical resistivity and conductivity, Isostructural
Abstract

The capacity of YMn 2 to undergo reversible hydrogenization makes this compound a potential candidate for hydrogen storage. This report describes the successful synthesis of YMn 2 H 6 from hexagonal C14 YMn 2 as well as calorimetric studies of hexagonal C14 YMn 2 , cubic C15 YMn 2 and their isostructural derivatives, YMn 2 H 6 and YMn 2 D 6 . Complementary structural and physical property characterizations include X-ray diffraction, electrical resistivity, and magnetic susceptibility measurements. Of particular interest is a hysteretic first-order phase transition in C15 YMn 2 near 100 K, which does not occur in C14 YMn 2 . Analysis of a specific heat anomaly that is associated with this transition reveals a substantial latent heat of 330 J/mol. No such anomalous specific heat exists in YMn 2 D 6 , suggesting that the transition is suppressed upon deuterization.

Published
2011
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38. Numerical Analysis of the Effect of Cope Hole on the Fatigue Strength of Corrugated Web Girders

Author

Rui Juan Jiang, Y.Y. Chen, W.X. Ouyang, Qingyuan Wang, and Zhi Yong Wang

Subjects
Engineering, Stress gradient, business.industry, Mechanical Engineering, Numerical analysis, Structural engineering, Welding, Flange, Fatigue limit, law.invention, Mechanics of Materials, law, Girder, General Materials Science, business, Stress concentration
Abstract

A common means of facilitating cross welding on the girder flange is to use cope hole on the girder web. This paper presents a study on the fatigue strength of the corrugated web girders with the cope hole using numerical analysis. Typical stress concentration behaviours are discussed relative to reported experimental results, and parameter variations are then used to study the stress gradient on the corrugated web as the influence of the cope hole. Based on the simplified cumulative fatigue summation implemented in fatigue post-processor, fatigue life predictions are presented with codified curves of AASHTO LRFD.

Published
2010
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39. Novel microfluidic and analytical approaches for screening engineered strains: Downscaling of S. cerevisae cultivations for lactic acid production

Author

Y.Y. Chen, Mario Rothbauer, H.Y.A. Wang, Matthias G. Steiger, Michael Sauer, Peter Ertl, Diethard Mattanovich, and Damiano Totaro

Subjects
chemistry.chemical_compound, Chromatography, Chemistry, Microfluidics, Bioengineering, General Medicine, Molecular Biology, Biotechnology, Downscaling, Lactic acid
Published
2018
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41. Comparative study on microstructures and mechanical properties of Q&P steels prepared with hot-rolled and cold-rolled C–Si–Mn sheets

Author

Y.Y. Cheng, G. Zhao, D.M. Xu, X.P. Mao, S.Q. Bao, and G.W. Yang

Subjects
Quenching and partitioning treatment, Hot-rolled sheet, Morphology of structures, Stability of retained austenite, Elongation, Mining engineering. Metallurgy, TN1-997
Abstract

In this study, we investigate the microstructures and mechanical properties of quenching and partitioning (Q&P) steels prepared with hot-rolled (HR) and cold-rolled (CR) sheets at different annealing temperatures (partial austenitisation). The ferrite and retained austenite are present in laths and blocks in HR-Q&P samples but are mainly blocky in CR-Q&P samples. Compared with CR-Q&P, the HR-Q&P samples have higher content of retained austenite, better elongation and higher product of strength and elongation (PSE). The lath-shaped retained austenite in HR-Q&P samples with a higher ratio of surface to volume is conducive to homogenization of carbon in austenite grains, thus improving the thermal stability and content of retained austenite. The lath-shaped retained austenite transforms into martensite obviously until the strain exceeds 5% and exhibits higher mechanical stability than coarse blocky retained austenite. When annealed at 810 °C, HR-Q&P and CR-Q&P samples present best PSEs. Indeed, the PSE of HR-810°C-Q&P sample is 62.8% higher than that of CR%-810°C-Q&P. The better elongation and higher PSE possessed by HR-810°C-Q&P sample are linked with the higher content of retained austenite and the presence of two kinds of retained austenite with different mechanical stability. The retained austenite with different mechanical stability in HR-810°C-Q&P sample, contributes to continuous transformation during tensile deformation, thereby improving the elongation. Meanwhile, the lath-shaped structures can delay the formation of voids and microcracks, thereby improving the elongation.

Published
2022
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42. Refining an optical switch for the Natural Light Guiding System

Author

A. J. W. Whang, Y.Y. Chen, K.Y. Chen, and K.H. Chou

Subjects
Sunlight, Engineering, Optical fiber, business.industry, Optical switch, Natural (archaeology), law.invention, law, Refining, Optoelectronics, Electrical and Electronic Engineering, business, Solar concentrator, Energy (signal processing)
Abstract

Many recent studies have focused on the use of sunlight to provide indoor lighting and save energy. One approach, the Natural Light Guiding System, uses a static solar concentrator, a fibre optic transmitter and a light emitter to collect sunlight, move it to where it is wanted and distribute it into a room. An important feature of this system is an optical switch that can be used to control and change the direction of the transmitted light. This paper describes the refinement of the optical switch. The refined optical switch uses two lenses to improve light absorption efficiency. The light switch provides light efficiency management controls, such as a switch on and off function and the capability of saving energy in a solar battery.

Published
2010
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43. A study of the probabilistic risk assessment to the dry storage system of spent nuclear fuel

Author

C.T. Liu, Y.Y. Chen, Y.C. Li, W.K. Cheng, W.C. Chen, K. Ting, and Kun-Chieh Chen

Subjects
Engineering, Dry cask storage, Probabilistic risk assessment, Power station, Waste management, business.industry, Mechanical Engineering, Nuclear power, Spent nuclear fuel, law.invention, Electricity generation, Mechanics of Materials, law, Nuclear power plant, General Materials Science, business, Spent fuel pool
Abstract

Due to the large power supply in the energy market since 1960s, the nuclear power planets have been consistently constructed throughout the world in order to maintain and supply sufficient fundamental power generation. Up to now, most of the planets have been operated to a point where the spent fuel pool has reached its design capacity volume. To prevent the plant from shutdown due to the spent fuel pool exceeding the design capacity, the dry cask storage can provides a solution for both the spent fuel pool capacity and the mid-term storage method for the spent fuel bundles at nuclear power planet. Currently, the dry cask storage system and relevant operating procedures have also gradually been deployed and consistently developed in order to facilitate the dry storage for the spent fuel bundles. In other words, spent fuel bundles dry storage and its safety has become an important issue and will directly affect the smooth operation of the plants once the spent fuel pool reaches its design capacity. Plants in the United States, Nuclear Regulatory Commission, the Office of Nuclear Material Safety and Safeguards (NMSS), the Office of Nuclear Regulatory Research (RES) and Spent Fuel Project Office (NMSS) have jointly developed a pilot methodology for probabilistic risk assessments. Adopting quantitative and qualitative evaluating methods to the subject BWR plants based on the handling, transfer and storage three phases. Obtaining the annual risk for one cask in terms of the individual probability of a prompt fatality within 1.6 km and a latent cancer fatality within 16 km can provide useful risk information for the subject BWR plant. This pilot study used NUREG-1864 [1] ,“A Pilot Probabilistic Risk Assessment of a Dry Cask Storage System at a Nuclear Power Planet”, related generic data and built prototype models for risk assessments in Taiwan Nuclear Power Plants. This pilot study investigated the handling, transfer and storage three phases to establish its risk evaluating methodologies, which includes initialing events, failure probabilities for canister and cask under mechanical loads and proceeded risk assessment for all three phases using quantitative fault tree analysis. The results of this study can be as a reference for future more detailed developments of the dry cask storage system risk assessments at Taiwan Nuclear Power Plants.

Published
2010
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44. Formation of Mg2Ni alloy layers and kinetic studies in the binary Mg–Ni system

Author

Hsun-Feng Hsu, Sheng Wei Lee, Shao Liang Cheng, and Y.Y. Chen

Subjects
Chemistry, Diffusion, Kinetics, Alloy, Metals and Alloys, Intermetallic, Analytical chemistry, Surfaces and Interfaces, engineering.material, Kinetic energy, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Phase (matter), Trench, Materials Chemistry, engineering, Physical chemistry, Crystallite
Abstract

article i nfo Available online 13 March 2009 We report here the study on the kinetics and growth of Mg2Ni alloy layers by solid-state reactions in the Mg-Ni system. After appropriate heat treatments, only polycrystalline Mg2Ni phase was found to form on the Mg/Ni interfaces and the grain sizes of Mg2Ni formed near the Mg side were found to be much smaller than those formed near the Ni side. Cross-sectional SEM examinations revealed that the Mg2Ni intermetallic layers grew following the diffusion-control process. During the formation of Mg2Ni layers, the dominant diffusing species was determined to be Ni by using the immobile trench markers. Furthermore, based on the marker analysis, the intrinsic and interdiffusion diffusivities for the Mg-Ni diffusion couples at different temperatures have been determined.

Published
2009
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45. PHYSICAL AND CHEMICAL MANIPULATION OF FLOWERING IN PINEAPPLE

Author

Y. Ko, S.H. Hung, L.Y. Shiu, Y.Y. Chen, M. Loganathan, W. C. Lien, C. H. Lin, Subbiyan Maruthasalam, and C. Yu

Subjects
chemistry.chemical_compound, Shoot apex, Horticulture, Materials science, chemistry, Inflorescence, Activated charcoal, Calcium carbide, Chemical manipulation, Botany
Published
2009
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46. Synthesis and Properties of Ca0.85(W1-xMox)O4:Eu0.15 Rare Earth Phosphors

Author

Zhao Xian Xiong, Y.Y. Chen, and C.X. Song

Subjects
business.industry, Chemistry, Mechanical Engineering, Rare earth, Analytical chemistry, Phosphor, medicine.disease_cause, Microstructure, Wavelength, Optics, Mechanics of Materials, medicine, General Materials Science, Emission spectrum, Luminescence, business, Ultraviolet, Excitation
Abstract

Rare earth phosphors of Ca0.85(W1-xMox)O4:Eu0.15 (x=0.00-0.50) were synthesized via solidstate reaction in air. The lattice parameters strongly depended on the x value, which was analyzed by the XRD patterns. Microstructures of the powders were observed by SEM. The phosphors could be effectively excitated by ultraviolet (UV) light (250-300nm) and blue light (464nm), which were showed with the excitation and emission spectra. With the increasing of x value, moreover, another emission peak of the sample which was excitated by UV light appeared and shifted to short wavelength, from 597 to 545 nm. The luminescence properties of the phosphors and energy transfer mechanism were also discussed.

Published
2008
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47. Effect of Boron on the Corrosion Properties of Al0.5CoCrCuFeNiBx High Entropy Alloys in 1N Sulfuric Acid

Author

Chien Ping Lee, Han Chang Shih, C.H. Wu, Y.Y. Chen, J.W. Yeh, and C.Y. Hsu

Subjects
chemistry.chemical_compound, Materials science, chemistry, High entropy alloys, Metallurgy, chemistry.chemical_element, Sulfuric acid, Boron, Corrosion
Abstract

High entropy alloys are a newly developed family of multi- component alloys composed of several major alloying elements, such as copper, nickel, aluminum, cobalt, chromium, iron, etc. Each element in the alloy system is between 5 at.-% and 35 at.- %. High entropy alloy has a lot of advantages regarding its mechanical, magnetic and electrochemical properties. This study discusses the corrosion resistance of Al0.5CoCrCuFeNiBx alloys with various amounts of boron addition. Surface morphology and EDS analysis confirmed that the addition of boron produced Cr and Fe borides. Therefore the content of Cr in the region besides borides precipitates was very scanty. The anodic polarization curves and electrochemical impedance spectra of Al0.5CoCrCuFeNiBx alloys, obtained in 1 N H2SO4 aqueous solution, clearly indicated that the general corrosion resistance decreases as the amounts of boron increases.

Published
2007
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48. Physical Scale Model Alternators as a Pulsed-Power Source Simulator

Author

Y.Y. Chen, John A. Mallick, and N. Shepard

Subjects
Alternator (automotive), Computer science, Electric generator, Pulsed power, DC motor, Electronic, Optical and Magnetic Materials, law.invention, Generator (circuit theory), law, Control system, Alternator, Electrical and Electronic Engineering, Simulation, Machine control
Abstract

Pulsed alternators configured as counter-rotating pairs are being considered as a potential pulsed-power source for electromagnetic launchers. The Institute for Advanced Technology is interested in studying the electrical and mechanical characteristics of such a pair of counter-rotating pulsed alternators; however, implementation and experimentation have only been attempted on a single subscale alternator machine that requires extensive laboratory support for operation. As a first step toward testing the electromechanical effects of counter-rotating alternators, two iron-core wound field alternators driven by dc motor prime movers were obtained and implemented as a scale model pulsed-power source simulator. These alternators were originally designed and fabricated at the Massachusetts Institute of Technology as physical scale models of 900-MVA utility alternators, which exhibit the same per-unit reactance and time constants as the full-scale machines. A digital signal processor was integrated into a real-time control system designed to maintain the two generators as an electrically coupled, counter-rotating generator pair. This paper documents the control system design, the incorporated control algorithm, and the automated test setup implemented for experimental data collection

Published
2007
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49. Experimental Results from a Physical Scale Model Alternator Pair as a Pulsed Power

Author

N. Shepard, Y.Y. Chen, and John A. Mallick

Subjects
Physics, Alternator (automotive), business.industry, Reactance, Electrical engineering, Electric generator, Thyristor, Compensated pulsed alternator, Linear alternator, Pulsed power, Field coil, Electronic, Optical and Magnetic Materials, law.invention, law, Electrical and Electronic Engineering, business
Abstract

The Institute for Advanced Technology is using a pair of physical scale model alternators as counter-rotating pulsed alternator simulators. These alternators have similar but not identical electrical characteristics. The original goal was to use these alternators to simulate a two-machine pulsed alternator system to study thyristor converter operation, with the two machines electrically connected at the output (dc side) of the thyristor (SCR) converter. Additional experiments were also run with the two alternators electrically connected at the input (ac side) of the thyristor converter. In the experiments, control algorithms were developed to test self-excitation and to discharge pulsed energy into various types of loads-resistive, inductive, and capacitive-to evaluate energy sharing from each alternator. Negative resistance circuits were implemented to adjust the field winding time constant of each alternator to achieve correct resistance/reactance ratio of full-scale pulsed alternators and to achieve equal energy discharge from each alternator

Published
2007
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