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3. Cancer bronchique à petites cellules de stade étendu : quoi de neuf ?

Author

Ocak, S., Moro-Sibilot, D., Aliouat, A., Berton, E., Fournel, P., and Toffart, A.-C.

Abstract

Cet article décrit les avancées récentes relatives à la prise en charge diagnostique et thérapeutique des cancers bronchiques à petites cellules de stade étendu. Une place particulière est faite au développement des inhibiteurs des points de contrôle immunitaire et des nouvelles molécules ciblant DLL3. Il cite aussi les points encore débattus autour de la radiothérapie thoracique et de l’irradiation prophylactique cérébrale. Enfin, les pistes de thérapie ciblant les anomalies de réparation des dommages de l’ADN sont évoquées.

Published
2024
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4. Statistics and prediction of vehicle-bridge collisions in Quebec

Author

Berton, E., Bouaanani, N., Lamarche, C.-P., and Roy, N.

Subjects
Engineering research, Bridges -- Properties, Traffic accidents -- Research, Engineering and manufacturing industries
Abstract

Vehicle-bridge collisions (VBCs) can compromise the safety of road users and cause major economic losses. This paper proposes and applies a methodology to investigate such events in Quebec. Relevant data have been collected from various sources and merged to provide a comprehensive database of VBCs that occurred in Quebec between 2000 and 2016. The developed database was used to carry out statistical analyses highlighting the main factors characterizing VBCs, such as vehicle's body type, bridge dimensions, prescribed speed limit, road configuration, road surface condition and lighting. The compiled database was georeferenced in an upgradable map that can be used efficiently to visualize the distribution and evolution of VBCs over a given region of Quebec. A VBC regression model was also developed based on k-fold crossvalidation. The proposed model can be updated regularly as new VBCs are reported and then used to identify bridges most likely to be affected by VBCs or prioritize actions to reduce the potential consequences. Key words: bridges, vehicle impact, statistics, regression, prediction, cross-validation. Les collisions entre un vehicule et un pont (CVP) peuvent compromettre la securite des usagers de la route et causer des pertes economiques importantes. Le present document propose et applique une methodologie pour etudier de tels evenements au Quebec. Des donnees pertinentes ont ete recueillies aupres de diverses sources et fusionnees pour fournir une base de donnees complete des CVP qui ont eu lieu au Quebec entre 2000 et 2016. La base de donnees developpee a ete utilisee pour effectuer des analyses statistiques mettant en evidence les principaux facteurs caracterisant les CVP, tels que le type de carrosserie, les dimensions du pont, la limite de vitesse prescrite, la configuration de la route, l'etat de la surface de la route et l'eclairage. La base de donnees compilee a ete georeferencee dans une carte evolutive qui peut etre utilisee efficacement pour visualiser la distribution ou l'evolution des CVP dans une region donnee du Quebec. Un modele de regression CVP a egalement ete developpe sur la base de la validation croisee repetee k fois. Le modele propose peut etre mis a jour regulierement au fur et a mesure que les nouvelles CVP sont signalees, puis utilise pour identifier les ponts les plus susceptibles d'etre touches par les CVP ou pour etablir l'ordre de priorite des mesures visant a reduire les consequences potentielles. [Traduit par la Redaction] Mots-cles: ponts, choc de vehicules, statistiques, regression, prediction, validation croisee., Introduction Vehicle-bridge collisions (VBCs) can be a serious threat to the structural integrity of bridges (i.e., damage, failure or collapse of piers, bent caps, foundations, decks, etc.), may compromise the [...]

Published
2021
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10. 1324P Durvalumab in treatment-naive, stage IV non-small cell lung cancer (NSCLC) patients (pts), with ECOG performance status (PS) 2-3 and high PD-L1 tumour expression: Results of IFCT-1802 SAVIMMUNE phase II trial

Author

Gounant, V., Greillier, L., Mascaux, C., Pinquie, F., Carmier, D., Moreau, L., Roch, B., Debieuvre, D., Dhalluin, X., Giroux-Leprieur, E., Berton, E., Rabeau, A., Raimbourg, J., Dixmier, A., Naltet, C., Khalil, A., Ezzeddine, L., Langlais, A., Morin, F., and Duruisseaux, M.

Published
2024
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11. Summary of work carried out in the main tasks of the UNSI project

Author

Braza, M., Berton, E., Allain, C., Favier, D., Maresca, C., Selmin, Vittorio, Evans, J., Schwarmborn, D., Weinman, K. A., Teupootahiti, E., Dervieux, A., Koobus, B., de C Henshaw, Michael J., Smith, Jonathan, Abbas, A., Guerra, J., Haase, W., Schweiger, J., Berggren, M., Alpesh, A., Karlsson, A., Winzell, B., Barakos, G., Drikakis, D., Girodroux-Lavigne, P., Bunge, U., Palacios, R., Climent, H., Hirschel, Ernst Heinrich, editor, Fujii, Kozo, editor, Haase, Werner, editor, van Leer, Bram, editor, Leschziner, Michael A., editor, Pandolfi, Maurizio, editor, Periaux, Jacques, editor, Rizzi, Arthur, editor, Roux, Bernard, editor, Selmin, Vittorio, editor, and Winzell, Bengt, editor

Published
2003
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12. Technical, partner reports containing method descriptions and concise presentation of important results

Author

Selmin, V., de C Henshaw, Michael J., Smith, Jonathan, Guerra, J. J., Abbas, A., Grashof, J., Haase, W., Schneider, M., Schweiger, J., Stettner, M., Guillemot, Stéphane, Roques, Olivier, Teupootahiti, Edwin, Aviation, Dassault, Catherall, D., Evans, J., Schwarmborn, D., Weinman, K., Berggren, M., Wallin, S., Wang, D., Johansson, C., Eliasson, P., Bouhadji, A., Bourdet, S., Braza, M., Hoarau, Y., Rodes, P., Tzabiras, G., Berton, E., Allain, C., Favier, D., Maresca, C., Patel, Alpesh, Hirsch, Charles, Girodroux-Lavigne, P., Grisval, J. P., Le Balleur, J. C., Mortchelewicz, G. D., Barakos, G., Drikakis, D., Winzell, B., Karlsson, A., Bunge, Ulf, Rung, Thomas, Thiele, Frank, Hirschel, Ernst Heinrich, editor, Fujii, Kozo, editor, Haase, Werner, editor, van Leer, Bram, editor, Leschziner, Michael A., editor, Pandolfi, Maurizio, editor, Periaux, Jacques, editor, Rizzi, Arthur, editor, Roux, Bernard, editor, Selmin, Vittorio, editor, and Winzell, Bengt, editor

Published
2003
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20. Computational fluid dynamics study of three-dimensional dynamic stall of various planform shapes

Author

Spentzos, A., Barakos, G.N., Badcock, K.J., Richards, B.E., Coton, F.N., Galbraith, R.A. McD., Berton, E., and Favier, D.

Subjects
Computational physics -- Models, Stalling (Aerodynamics) -- Research, Stalling (Aerodynamics) -- Models, Airplanes -- Wings, Airplanes -- Design and construction, Airplanes -- Mechanical properties, Aerospace and defense industries, Business, Science and technology
Abstract

Numerical simulation of 3-D dynamic stall has been undertaken using computational fluid dynamics. As a first step, validation calculations have been performed for cases in which experimental data were available. Although the amount and quality of the experimental data available for 3-D dynamic stall does not match what is available for 2-D cases, the computational fluid dynamics was found capable of predicting this complex 3-D flow with good accuracy. Once confidence on the computational fluid dynamics method was established, further calculations were conducted for several wing planforms. The calculations revealed the detailed structure of the 3-D dynamic stall vortex and its interaction with the tip vortex. Remarkably, strong similarities in the flow topology were identified for wings of very different planforms.

Published
2007

21. Embedded laser Doppler velocimetry boundary-layer investigation on a tilt-rotor blade

Author

Barla, C., Berton, E., Favier, D., and Maresca, C.

Subjects
Ground-effect machines -- Mechanical properties, Ground-effect machines -- Equipment and supplies, Boundary layer -- Research, Boundary layer -- Models, Laser Doppler velocimeter -- Usage, Aerospace and defense industries, Business, Science and technology
Abstract

A fundamental study is made of a rotating boundary layer (BL) in the inboard region of a tilt-rotor blade, using an embedded laser Doppler velocimetry probe inside a rotating blade. Velocity measurements have been performed to get insight into the BL behavior around a blade section close to the rotor hub. BL transition and separation phenomena are investigated on the basis of both chordwise and spanwise velocity profiles measured for different collective pitch angles on a two-bladed hovering rotor. The velocity experimental data bank appears to be in good agreement with theoretical velocity profiles in attached flow conditions (laminar, transitional, or turbulent). Moreover, validation of a transitional criterion based on the second thickness of energy [[delta].sub.3] of the BL is extended to the rotational flow configuration. Usually such a configuration classically exhibits a separation of the BL for high collective pitch angles. However, in the particular case of a high twisted tilt-rotor blade operating in hover, centrifugal effects are shown to be responsible for an important delay in the BL separation process.

Published
2006

22. Ross procedure and aortic valve repair: long-term echocardiographic outcomes, quality of life and physical activity of different aortic valve surgery procedures

Author

Bianco, F, primary, Colaneri, M, additional, Bucciarelli, V, additional, Surace, FC, additional, Iezzi, FC, additional, Primavera, M, additional, Biasi, AC, additional, Berton, E, additional, Baldoni, M, additional, Baldinelli, A, additional, Pozzi, M, additional, and Gallina, S, additional

Published
2021
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24. OBALPA : influence du nombre de molécules bronchodilatatrices sur les bénéfices cliniques de la réhabilitation respiratoire

Author

Berton, E., primary, Devouassoux, G., additional, Piperno, D., additional, Falchero, L., additional, Muti, D., additional, Chatte, G., additional, Court-Fortune, I., additional, Freymond, N., additional, Bertocchi, M., additional, Camara, B., additional, Kelkel, E., additional, Pradat, P., additional, and Pison, C., additional

Published
2020
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25. Hover performance prediction using full-potential method and comparison with experiments

Author

Berton, E., Favier, d., and Maresca, C.

Subjects
Helicopters -- Aerodynamics, Laser Doppler velocimeter -- Usage, Rotors (Helicopters) -- Design and construction, Aerospace and defense industries, Business, Science and technology
Abstract

Research is presented concerning the development of an experimental and computational method of analyzing the airflow around the rotor blades of a hovering helicopter. Laser velocimetry is used to measure the flowfield.

Published
2000

28. Experimental and numerical investigation of rotor aerodynamics in forward flight

Author

Berenger, T., Favier, D., Maresca, C., and Berton, E.

Subjects
Rotors (Helicopters) -- Aerodynamics, Aerodynamics -- Research, Aerospace and defense industries, Business, Science and technology
Abstract

Experimental and numerical studies were conducted on the aerodynamic field of a model rotor in forward flight. The flowfield in the blade and its near wake were characterized in terms of overall airloads, vortex path geometry and three-dimensional velocity field. Wake analysis code prediction efficiency was validated against experiments on the tip vortex path and blade span circulation distribution.

Published
1997

29. The metabolic exercise test data combined with Cardiac And Kidney Indexes (MECKI) score and prognosis in heart failure. A validation study

Author

Corrà, Ugo, Agostoni, Piergiuseppe, Giordano, Andrea, Cattadori, Gaia, Battaia, Elisa, La Gioia, Rocco, Scardovi, Angela B., Emdin, Michele, Metra, Marco, Sinagra, Gianfranco, Limongelli, Giuseppe, Raimondo, Rosa, Federica, Re, Guazzi, Marco, Belardinelli, Romualdo, Parati, Gianfranco, Magri', Damiano, Fiorentini, Cesare, Cicoira, Mariantonietta, Salvioni, Elisabetta, Giovannardi, Marta, Veglia, Fabrizio, Mezzani, Alessandro, Scrutinio, Domenico, Di Lenarda, Andrea, Ricci, Roberto, Apostolo, Anna, Iorio, Anna Maria, Paolillo, Stefania, Palermo, Pietro, Contini, Mauro, Vassanelli, Corrado, Passino, Claudio, Giannuzzi, Pantaleo, Piepoli, Massimo F., MECKI ScoreResearch Group, Other Members of the MECKI Score research Group, Antonioli, L., Segurini, C., Bertella, E., Farina, S., Bovis, F., Pietrucci, F., Malfatto, G., Roselli, T., Buono, A., Calabrò, R., De Maria, R., Santoro, D., Campanale, S., Caputo, D., Bertipaglia, D., Berton, E., Corrà, Ugo, Agostoni, Piergiuseppe, Giordano, Andrea, Cattadori, Gaia, Battaia, Elisa, La Gioia, Rocco, Scardovi, Angela B., Emdin, Michele, Metra, Marco, Sinagra, Gianfranco, Limongelli, Giuseppe, Raimondo, Rosa, Re, Federica, Guazzi, Marco, Belardinelli, Romualdo, Parati, Gianfranco, Magrì, Damiano, Fiorentini, Cesare, Cicoira, Mariantonietta, Salvioni, Elisabetta, Giovannardi, Marta, Veglia, Fabrizio, Mezzani, Alessandro, Scrutinio, Domenico, DI LENARDA, Andrea, Ricci, Roberto, Apostolo, Anna, Iorio, Anna Maria, Paolillo, Stefania, Palermo, Pietro, Contini, Mauro, Vassanelli, Corrado, Passino, Claudio, Giannuzzi, Pantaleo, Piepoli, Massimo F., Corra, U., Agostoni, P., Giordano, A., Cattadori, G., Battaia, E., La Gioia, R., Scardovi, A. B., Emdin, M., Metra, M., Sinagra, G., Limongelli, G., Raimondo, R., Re, F., Guazzi, M., Belardinelli, R., Parati, G., Magri, D., Fiorentini, C., Cicoira, M., Salvioni, E., Giovannardi, M., Veglia, F., Mezzani, A., Scrutinio, D., Di Lenarda, A., Ricci, R., Apostolo, A., Iorio, A. M., Paolillo, S., Palermo, P., Contini, M., Vassanelli, C., Passino, C., Giannuzzi, P., Piepoli, M. F., Corrà, U, Agostoni, P, Giordano, A, Cattadori, G, Battaia, E, La Gioia, R, Scardovi, A, Emdin, M, Metra, M, Sinagra, G, Limongelli, G, Raimondo, R, Re, F, Guazzi, M, Belardinelli, R, Parati, G, Magrì, D, Fiorentini, C, Cicoira, M, Salvioni, E, Giovannardi, M, Veglia, F, Mezzani, A, Scrutinio, D, Di Lenarda, A, Ricci, R, Apostolo, A, Iorio, A, Paolillo, S, Palermo, P, Contini, M, Vassanelli, C, Passino, C, Giannuzzi, P, and Piepoli, M

Subjects
Male, medicine.medical_treatment, Predictive Value of Test, 030204 cardiovascular system & hematology, Kidney Function Tests, Severity of Illness Index, 0302 clinical medicine, score, 030212 general & internal medicine, Heart transplantation, education.field_of_study, Ejection fraction, Heart Function Test, Stroke volume, Middle Aged, Prognosis, Predictive value of tests, Heart Function Tests, Cardiology, Female, Cardiology and Cardiovascular Medicine, Human, medicine.medical_specialty, Prognosi, Population, Renal function, Heart failure, Prognosis, score, Lower risk, Follow-Up Studie, 03 medical and health sciences, Oxygen Consumption, Predictive Value of Tests, Internal medicine, medicine, Humans, medicine (all), education, Aged, Kidney Function Test, business.industry, heart failure, prognosis, score, aged, exercise test, female, follow-up studies, heart function tests, heart transplantation, humans, kidney function tests, male, middle aged, oxygen consumption, predictive value of tests, prognosis, severity of illness index, stroke volume, cardiology and cardiovascular medicine, Stroke Volume, medicine.disease, Exercise Test, Follow-Up Studies, Heart Failure, Heart Transplantation, business
Abstract

Background The Metabolic Exercise test data combined with Cardiac and Kidney Indexes (MECKI) score is a prognostic model to identify heart failure (HF) patients at risk for cardiovascular mortality (CVM) and urgent heart transplantation (uHT) based on 6 routine clinical parameters: hemoglobin, sodium, kidney function by the Modification of Diet in Renal Disease (MDRD) equation, left ventricle ejection fraction (LVEF), percentage of predicted peak oxygen consumption (VO2) and VE/VCO2 slope. Objectives MECKI score must be generalizable to be considered useful: therefore, its performance was validated in a new sequence of HF patients. Methods Both the development (MECKI-D) and the validation (MECKI-V) cohorts were composed of consecutive HF patients with LVEF < 40% able to perform a symptom-limited cardiopulmonary exercise testing. The CVM or uHT rates were analyzed at one, two and three years in both cohorts: all patients with a censoring time shorter than the scheduled follow-up were excluded, while those with events occurring after 1, 2 and 3 years were considered as censored. Results MECKI-D and MECKI-V consisted of 2009 and 992 patients, respectively. MECKI-V patients had a higher LVEF, higher peak VO2 and lower VE/VCO2 slope, higher prescription of beta-blockers and device therapy: after the 3-year follow-up, CVM or uHT occurred in 206 (18%) MECKI-D and 44 (13%) MECKI-V patients (p < 0.000), respectively. MECKI-V AUC values at one, two and three years were 0.81 ± 0.04, 0.76 ± 0.04, and 0.80 ± 0.03, respectively, not significantly different from MECKI-D. Conclusions MECKI score preserves its predictive ability in a HF population at a lower risk.

Published
2016

31. Metabolic exercise data combined with cardiac and kidney indexes: MECKI score. Predictive role in cardiopulmonary exercise testing with low respiratory exchange ratio in heart failure

Author

Corrà, U, Agostoni, P, Piepoli, Mf, Giordano, A, Mezzani, A, Giannuzzi, P, Cattadori, G, Fiorentini, C, Salvioni, E, Giovannardi, M, Veglia, F, Apostolo, A, Palermo, P, Contini, M, Vignati, C, Farina, S, Bovis, F, Cicoira, M, Vassanelli, C, La Gioia, R, Scrutinio, D, Passantino, A, Santoro, D, Campanale, S, Caputo, D, Scardovi, Ab, Ricci, R, Emdin, Michele, Metra, M, Dei Cas, L, Sinagra, G, Berton, E, Limongelli, G, Iorio, Am, Roselli, T, Buono, A, Calabrò, R, Raimondo, R, Vaninetti, R, Bertipaglia, D, Re, F, Guazzi, M, Belardinelli, R, Pietrucci, F, Parati, G, Magrì, D, Di Lenarda, A, Paolillo, S, Perrone Filardi, P, Passino, Claudio, Pastormerlo, Luigi Emilio, Malfatto, G, Caravita, S., Corrà, Ugo, Agostoni, Piergiuseppe, Piepoli, Massimo F., Giordano, Andrea, Mezzani, Alessandro, Giannuzzi, Pantaleo, Cattadori, Gaia, Fiorentini, Cesare, Salvioni, Elisabetta, Giovannardi, Marta, Veglia, Fabrizio, Apostolo, Anna, Palermo, Pietro, Contini, Mauro, Vignati, Carlo, Farina, Stefania, Bovis, Francesca, Cicoira, Mariantonietta, Vassanelli, Corrado, La Gioia, Rocco, Scrutinio, Domenico, Passantino, Andrea, Santoro, Daniela, Campanale, Saba, Caputo, Domenica, Scardovi, Angela B., Ricci, Roberto, Emdin, Michele, Metra, Marco, Dei Cas, Livio, Sinagra, Gianfranco, Berton, Emanuela, Limongelli, Giuseppe, Iorio, Anna Maria, Roselli, Teo, Buono, Andrea, Calabro', Raffaele, Raimondo, Rosa, Vaninetti, Raffaella, Bertipaglia, Donatella, Re, Federica, Guazzi, Marco, Belardinelli, Milano Romualdo, Pietrucci, Francesca, Parati, Gianfranco, Magrì, Damiano, Di Lenarda, Andrea, Paolillo, Stefania, Perrone Filardi, Pasquale, Passino, Claudio, Pastormerlo, Luigi E., Malfatto, Gabriella, Corrà, U, Agostoni, P, Piepoli, M, Giordano, A, Mezzani, A, Giannuzzi, P, Cattadori, G, Fiorentini, C, Salvioni, E, Giovannardi, M, Veglia, F, Apostolo, A, Palermo, P, Contini, M, Vignati, C, Farina, S, Bovis, F, Cicoira, M, Vassanelli, C, La Gioia, R, Scrutinio, D, Passantino, A, Santoro, D, Campanale, S, Caputo, D, Scardovi, A, Ricci, R, Emdin, M, Metra, M, Dei Cas, L, Sinagra, G, Berton, E, Limongelli, G, Iorio, A, Roselli, T, Buono, A, Calabrò, R, Raimondo, R, Vaninetti, R, Bertipaglia, D, Re, F, Guazzi, M, Belardinelli, M, Pietrucci, F, Parati, G, Magrì, D, Di Lenarda, A, Paolillo, S, Perrone Filardi, P, Passino, C, Pastormerlo, L, Malfatto, G, Calabrò, Raffaele, and DI LENARDA, Andrea

Subjects
Male, medicine.medical_specialty, Cardiopulmonary exercise, Heart failure, Oxygen consumption, Prognosis, Respiratory quotient, Prognosi, Renal function, Respiratory physiology, Kidney Function Tests, Severity of Illness Index, Predictive Value of Tests, Internal medicine, Severity of illness, medicine, Humans, Respiratory exchange ratio, Aged, Kidney, business.industry, Medicine (all), Middle Aged, medicine.disease, medicine.anatomical_structure, Predictive value of tests, Exercise Test, Respiratory Mechanics, Cardiology, Female, Energy Metabolism, Cardiology and Cardiovascular Medicine, business, cardiopulmonary exercise, heart failure, oxygen consumption, prognosis, respiratory quotient, aged, energy metabolism, exercise test, female, humans, kidney function tests, male, middle aged, predictive value of tests, respiratory mechanics, severity of illness index, cardiology and cardiovascular medicine
Abstract

n/a

Published
2015

41. The long QT syndrome

Author

Ferrara G., Berton E., Germani C., Marzuillo P., Bonazza P., D'Alfonso R., Barbi E., Ferrara, G., Berton, E., Germani, C., Marzuillo, P., Bonazza, P., D'Alfonso, R., and Barbi, E.

Subjects
Drugs prolonging QT, Congenital arrhythmia, Long QT syndrome, Syncope
Abstract

The long QT syndrome (LQTS) is an arrhythmogenic syndrome due to cardiac ion channel disorders characterized by prolonged QT interval on ECG (QTc >440 ms for male, >460 ms for female) and the most common presentations are syncope, seizures, cardiac arrest and sudden death. Many different congenital forms have been identified but also an acquired form due to specific drugs, hypokalaemia, or hypomagnesemia is known. Familiarity is the leading risk factor. LQTS should be suspected in case of any syncope in order to perform ECG and start proper therapy. To identify and remove risk factors it is necessary to avoid potentially life-threatening arrhythmia in these patients.

Published
2014

42. Air pollution trends in the EMEP region between 1990 and 2012. Joint Report of the EMEP Task Force on Measurements and Modelling (TFMM), Chemical Co-ordinating Centre (CCC), Meteorological Synthesizing Centre-East (MSC-E), Meteorological Synthesizing Centre-West (MSC-W)

Author

Colette, A., Aas, W., Banin, L., Braban, C., Ferm, M., Ortiz, A., Ilyin, I., Mar, K., Pandolfi, M., Putaud, J., Shatalov, V., Solberg, S., Spindler, G., Tarasova, O., Vana, M., Adani, M., Almodovar, P., Berton, E., Bessagnet, B., Bohlin-Nizzetto, P., Boruvkova, J., Breivik, K., Briganti, G., Cappelletti, A., Cuvelier, K., Derwent, R., D'Isidoro, M., Fagerli, H., Funk, C., Vivanco, M., Haeuber, R., Hueglin, C., Jenkins, S., Kerr, J., de Leeuw, F., Lynch, J., Manders, A., Mircea, M., Pay, M., Pritula, D., Querol, X., Raffort, V., Reiss, I., Roustan, Y., Sauvage, S., Scavo, K., Simpson, D., Smith, R., Tang, Y., Theobald, M., Tørseth, K., Tsyro, S., van Pul, A., Vidic, S., Wallasch, M., and Wind, P.

Published
2016

45. Fragmentation of ionized liquid helium droplets: A new interpretation.

Author

Callicoatt, Berton E. and Forde, Kirk

Subjects
*HELIUM, *FRAGMENTATION reactions, *MOLECULAR beams
Abstract

Investigates the fragmentation pattern of neutral helium clusters during electron impact ionization. Mechanism of dissipating the ionization energy; Estimation of the mean size of helium atoms; Use of molecular beam source to record the fragmentation pattern of helium clusters; Details on the ionization process.

Published
1998
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46. Charge transfer within He clusters.

Author

Callicoatt, Berton E., Mar, David D., Apkarian, V. A., and Janda, Kenneth C.

Subjects
*MASS spectrometry, *CHARGE transfer, *MOLECULES
Abstract

Mass spectrometric measurements of clusters containing N helium atoms and an NO molecule yield probabilities for charge transfer from He+ to NO that range from 0.8±0.1 for =540 to 0.02±0.02 for =15 000. From this we estimate that the He+ hole hops approximately 70 times before localization at a He+2 core. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
1996
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47. Capture and ionization of argon within liquid helium droplets.

Author

Callicoatt, Berton E. and Forde, Kirk

Subjects
*HELIUM, *IONIZATION (Atomic physics), *MICROCLUSTERS
Abstract

Examines the role of charge transfer and fragmentation in the electron impact ionization of argon doped helium clusters. Evaporation of helium atoms; Fragmentation distributions of cluster containing a single xenon atom; Application of positive-hole resonant-hopping mechanism.

Published
1998
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48. Charge transfer and fragmentation of liquid helium droplets doped with xenon

Author

Berton E. Callicoatt, Thomas Ruchti, and Kenneth C. Janda

Subjects
Chemistry, General Physics and Astronomy, chemistry.chemical_element, Ion, Xenon, Fragmentation (mass spectrometry), Excited state, Ionization, Atom, Physics::Atomic and Molecular Clusters, Physics::Atomic Physics, Physical and Theoretical Chemistry, Atomic physics, Electron ionization, Helium
Abstract

The ionization and fragmentation of clusters containing 1100, 2200, 2800 or 3300 helium atoms, on average, and between one and four Xe atoms are studied by electron impact mass spectrometry. The results are quite different from those of earlier studies of helium clusters containing Ne and Ar atoms. The observation of the Xe+ fragment is much more probable for ionization of clusters containing a single Xe atom than is the observation of Ne+ or Ar+ for clusters that contain a single Ne or Ar atom. Also, clusters that contain two Xe atoms are much less likely to yield Xe2+ compared to the analogous process for clusters containing two Ne or Ar atoms. These differences are attributed to the fact that the charge transfer from He+ to Xe can lead to electronically excited Xe+ ions. Charge transfer from He+ to Xe is not substantially more probable than from He+ to Ne or Ar. The changes of the charge transfer probability and the fragmentation patterns with cluster size are discussed.

Published
2000

49. Scompenso e...polmoni

Author

Pivetta, A., Berton, E., Merlo, M., Perkan, A., LO GIUDICE, F., Sinagra, Gianfranco, DI LENARDA, A., Pivetta, A., Berton, E., Merlo, M., Perkan, A., LO GIUDICE, F., Sinagra, Gianfranco, and DI LENARDA, A.

Published
2007

50. Charge transfer and fragmentation of liquid helium clusters that contain one or more neon atoms

Author

Kenneth C. Janda, Kirk Förde, Thomas Ruchti, Berton E. Callicoatt, and Henrik Ludwigs

Subjects
Liquid helium, General Physics and Astronomy, chemistry.chemical_element, Astrophysics::Cosmology and Extragalactic Astrophysics, Ion, law.invention, Neon, chemistry, Fragmentation (mass spectrometry), law, Atom, Physics::Atomic and Molecular Clusters, Cluster (physics), Physical and Theoretical Chemistry, Atomic physics, Electron ionization, Helium
Abstract

An investigation of the electron impact ionization and fragmentation of helium clusters that contain Ne atoms and Nek subclusters has been performed. The charge transfer probability from He+ to Ne and the branching ratios for fragmentation of the Nek subclusters were found by analyzing the dependence of the ion signal intensities on the Ne pressure in the “pickup” region. The measured charge transfer probability from He+ to Ne ranges from 0.06±0.01 for clusters of mean original size 〈N〉=3300 to 0.43±0.02 for 〈N〉=1100. Charge transfer to a single Ne atom within the helium clusters never yields bare Ne+ ions. Instead, fragments of the type NeHen+ are produced. The charge transfer from He+ to Ne2 subclusters yields mainly Ne2+ for smaller initial cluster sizes, but NeHen+ or Ne2Hen+ fragments are more probable for larger clusters. This shows that He droplets of a few thousand atoms are able to cage Ne2 subclusters by dissipating the entire energy released by charge transfer and formation and vibrational rela...

Published
1998

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