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Laurent Brochard - One of the best experts on this subject based on the ideXlab platform.
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Can Proportional ventilation Modes facilitate exercise in critically ill patients? A physiological cross-over study
Annals of Intensive Care, 2017Co-Authors: Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-christophe Marie Richard, Laurent BrochardAbstract:Background Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a Proportional Mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and Proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise. Methods Prospective pilot randomized cross-over study performed in a medico-surgical ICU. Patients requiring mechanical ventilation >48 h were enrolled. At initiation, the patients underwent an incremental workload test on a cycloergometer to determine the maximum level capacity. The next day, 2 15-min exercise, at 60% of the maximum capacity, were performed while patients were randomly ventilated with PSV and PAV+ or NAVA. The change in oxygen consumption (ΔVO_2, indirect calorimetry) and the work efficiency (ratio of ΔVO_2 per mean power) were computed. Results Ten patients were examined, 6 ventilated with PSV/PAV+ and 4 with PSV/NAVA. Despite the same mean inspiratory pressure at baseline between the Modes, baseline VO_2 (median, IQR) was higher during Proportional ventilation (301 ml/min, 270–342) compared to PSV (249 ml/min, 206–353). Exercise with PSV was associated with a significant increase in VO_2 (ΔVO_2, median, IQR) (77.6 ml/min, 59.9–96.5), while VO_2 did not significantly change during exercise with Proportional Modes (46.3 ml/min, 5.7–63.7, p
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Can Proportional ventilation Modes facilitate exercise in critically ill patients? A physiological cross-over study
Annals of intensive care, 2017Co-Authors: Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-christophe M. Richard, Laurent BrochardAbstract:Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a Proportional Mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and Proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise. Prospective pilot randomized cross-over study performed in a medico-surgical ICU. Patients requiring mechanical ventilation >48 h were enrolled. At initiation, the patients underwent an incremental workload test on a cycloergometer to determine the maximum level capacity. The next day, 2 15-min exercise, at 60% of the maximum capacity, were performed while patients were randomly ventilated with PSV and PAV+ or NAVA. The change in oxygen consumption (ΔVO2, indirect calorimetry) and the work efficiency (ratio of ΔVO2 per mean power) were computed. Ten patients were examined, 6 ventilated with PSV/PAV+ and 4 with PSV/NAVA. Despite the same mean inspiratory pressure at baseline between the Modes, baseline VO2 (median, IQR) was higher during Proportional ventilation (301 ml/min, 270–342) compared to PSV (249 ml/min, 206–353). Exercise with PSV was associated with a significant increase in VO2 (ΔVO2, median, IQR) (77.6 ml/min, 59.9–96.5), while VO2 did not significantly change during exercise with Proportional Modes (46.3 ml/min, 5.7–63.7, p
Evangelia Akoumianaki - One of the best experts on this subject based on the ideXlab platform.
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Can Proportional ventilation Modes facilitate exercise in critically ill patients? A physiological cross-over study
Annals of Intensive Care, 2017Co-Authors: Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-christophe Marie Richard, Laurent BrochardAbstract:Background Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a Proportional Mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and Proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise. Methods Prospective pilot randomized cross-over study performed in a medico-surgical ICU. Patients requiring mechanical ventilation >48 h were enrolled. At initiation, the patients underwent an incremental workload test on a cycloergometer to determine the maximum level capacity. The next day, 2 15-min exercise, at 60% of the maximum capacity, were performed while patients were randomly ventilated with PSV and PAV+ or NAVA. The change in oxygen consumption (ΔVO_2, indirect calorimetry) and the work efficiency (ratio of ΔVO_2 per mean power) were computed. Results Ten patients were examined, 6 ventilated with PSV/PAV+ and 4 with PSV/NAVA. Despite the same mean inspiratory pressure at baseline between the Modes, baseline VO_2 (median, IQR) was higher during Proportional ventilation (301 ml/min, 270–342) compared to PSV (249 ml/min, 206–353). Exercise with PSV was associated with a significant increase in VO_2 (ΔVO_2, median, IQR) (77.6 ml/min, 59.9–96.5), while VO_2 did not significantly change during exercise with Proportional Modes (46.3 ml/min, 5.7–63.7, p
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Can Proportional ventilation Modes facilitate exercise in critically ill patients? A physiological cross-over study
Annals of intensive care, 2017Co-Authors: Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-christophe M. Richard, Laurent BrochardAbstract:Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a Proportional Mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and Proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise. Prospective pilot randomized cross-over study performed in a medico-surgical ICU. Patients requiring mechanical ventilation >48 h were enrolled. At initiation, the patients underwent an incremental workload test on a cycloergometer to determine the maximum level capacity. The next day, 2 15-min exercise, at 60% of the maximum capacity, were performed while patients were randomly ventilated with PSV and PAV+ or NAVA. The change in oxygen consumption (ΔVO2, indirect calorimetry) and the work efficiency (ratio of ΔVO2 per mean power) were computed. Ten patients were examined, 6 ventilated with PSV/PAV+ and 4 with PSV/NAVA. Despite the same mean inspiratory pressure at baseline between the Modes, baseline VO2 (median, IQR) was higher during Proportional ventilation (301 ml/min, 270–342) compared to PSV (249 ml/min, 206–353). Exercise with PSV was associated with a significant increase in VO2 (ΔVO2, median, IQR) (77.6 ml/min, 59.9–96.5), while VO2 did not significantly change during exercise with Proportional Modes (46.3 ml/min, 5.7–63.7, p
M Ambriola - One of the best experts on this subject based on the ideXlab platform.
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A TRD for space borne apparatus
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2006Co-Authors: M Ambriola, N. Mirizzi, Francesco Cafagna, M Circella, C De Marzo, Roberto Bellotti, Nicola Giglietto, Bartolomeo Marangelli, E. Barbarito, M. MongelliAbstract:Abstract A Transition Radiation Detector (TRD), has been built to be used as charged particle identifier in satellite born apparatus. Originally conceived to be used in the PAMELA telescope, this TRD has been qualified for space as well. The compact design and the low power consumption make this detector suitable to be used in space researches in which identification is required for particle of relativistic energies (i.e. with Lorentz factor ( γ ) > 1000 . In this TRD, carbon fibers are used as radiator material, and 1024 straw tubes as sensitive detectors. All components are piled up in nine sensitive layers of radiators and straws working in Proportional Mode using a Xe – CO 2 gas mixture. The detector characteristics will be described along with its performances studied having exposed the detector to both cosmic rays and particle beams at CERN.
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A Transition Radiation Detector for space borne apparatus
2005Co-Authors: M Ambriola, N. Mirizzi, M. Romita, M Circella, C De Marzo, Roberto Bellotti, Nicola Giglietto, E. Barbarito, M. Mongelli, M. RuppiAbstract:A Transition Radiation Detector (TRD), has been built to be used as charged particle identier in satellite born apparatus. Originally conceived to be used in the PAMELA telescope, this TRD has been qualied for space as well. The compact design and the low power consumption, make this detector, suitable to be used in space researches in which identication is required for particle of relativistic energies (i.e. with Lorentz factor 1000). In this TRD, carbon bers are used as radiator material, and 1024 straw tubes, as sensitive detectors. All components are piled up in 9 sensitive layers of radiators and straws working in Proportional Mode using a Xe-CO gas mixture. The detector characteristics will be described along with its performances studied having exposed the detector to both cosmic rays and particle beams at CERN.
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The transition radiation detector of the PAMELA space mission
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2004Co-Authors: M Ambriola, N. Mirizzi, M. Romita, Francesco Cafagna, M Circella, C De Marzo, Roberto Bellotti, Nicola Giglietto, Bartolomeo Marangelli, P SpinelliAbstract:PAMELA space mission objective is to flight a satellite-borne magnetic spectrometer built to fulfill the primary scientific goals of detecting antiparticles (antiprotons and positrons) and to measure spectra of particles in cosmic rays. The PAMELA telescope is composed of: a silicon tracker housed in a permanent magnet, a time-of-flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD is composed of nine sensitive layers of straw tubes working in Proportional Mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD characteristics will be described along with its performances studied at both CERN-PS and CERN-SPS facilities, using electrons, pions, muons and protons of different momenta.
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The transition radiation detector of the PAMELA space mission
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2004Co-Authors: M Ambriola, N. Mirizzi, M. Romita, Francesco Cafagna, M Circella, C De Marzo, Roberto Bellotti, Nicola Giglietto, Bartolomeo Marangelli, P SpinelliAbstract:PAMELA space mission objective is to flight a satellite-borne magnetic spectrometer built to fulfill the primary scientific goals of detecting antiparticles (antiprotons and positrons) and to measure spectra of particles in cosmic rays. The PAMELA telescope is composed of: a silicon tracker housed in a permanent magnet, a time-of-flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD is composed of nine sensitive layers of straw tubes working in Proportional Mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD characteristics will be described along with its performances studied at both CERN-PS and CERN-SPS facilities, using electrons, pions, muons and protons of different momenta. (C) 2003 Elsevier B.V. All rights reserved
Shunji Kishimoto - One of the best experts on this subject based on the ideXlab platform.
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Measurements of 73-keV X-ray time spectrum with avalanche-photodiode scintillation detector using Bi2O3-nanoparticle-doped plastic scintillator
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2020Co-Authors: Shunji Kishimoto, Masanori Koshimizu, Rie Haruki, Fumiyuki Hiyama, Fumihiko NishikidoAbstract:Abstract Time spectra of 73-keV X-rays were successfully observed with a scintillation detector using a Bi2O3-nanoparticle-doped plastic scintillator (PLS) and silicon avalanche photodiode (Si-APD). A 5 wt% Bi2O3-nanoparticle-doped PLS was fabricated and cut out to be ∼ 3 . 0 × 3 . 0 mm and 0.9 mm thick, and it was mounted on a Si-APD operating in Proportional Mode. An organic scintillator of [2-(4-tert-butylphenyl)-5-(4-phenylphenyl)]-1,3,4-oxadiazole was used for the PLS by 1.68 mol% of polystyrene solvent. When the PLS and Si-APD were cooled to − 30° C, a good time resolution of 0.35 ns (full width at half maximum) was obtained for 73.04-keV X-rays when measuring a time structure of the multibunch Mode in synchrotron ring operation. The Si-APD scintillation detector mounting a Bi2O3-nanoparticle-doped PLS can be applied well to research fields that need both a high detection efficiency and a subnanosecond time resolution with a photon energy of more than 70 keV, such as synchrotron radiation nuclear resonant scattering on 193Ir.
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Measurement of nuclear resonant scattering on 61 Ni with fast scintillation detector using Proportional-Mode silicon avalanche photodiode
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2018Co-Authors: Keisuke Inoue, Yasuhiro Kobayashi, Yoshitaka Yoda, Masanori Koshimizu, Fumihiko Nishikido, Rie Haruki, Shunji KishimotoAbstract:Abstract We developed a new scintillation timing detector using a Proportional-Mode silicon avalanche photodiode (Si-APD) for synchrotron radiation nuclear resonant scattering. We report on the nuclear forward scattering measurement on 61Ni with a prototype detector using a lead-loaded plastic scintillator (EJ-256, 3 mm in diameter and 2 mm in thickness), mounted on a Proportional-Mode Si-APD. Using synchrotron X-rays of 67.41 keV, we successfully measured the time spectra of nuclear forward scattering on 61Ni enriched metal foil and 61Ni86V14 alloy. The prototype detector confirmed the expected dynamical beat structure with a time resolution of 0.53 ns (FWHM).
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Fast Scintillation X-Ray Detector Using Proportional-Mode Si-APD and a HfO 2 -Nanoparticle-Doped Plastic Scintillator
IEEE Transactions on Nuclear Science, 2018Co-Authors: Keisuke Inoue, Masanori Koshimizu, Fumihiko Nishikido, Rie Haruki, Fumiyuki Hiyama, Kohei Asai, Shunji KishimotoAbstract:We developed a new fast scintillation detector using Proportional-Mode silicon avalanche photodiode (Si-APD) for nuclear forward scattering experiments using high-energy synchrotron X-rays >30 keV. After a test of a prototype detector with a lead-loaded plastic scintillator (EJ-256, Eljen Technology) and Proportional-Mode Si-APD (S8664-3796(X), Hamamatsu Photonics) as a photodetector, we fabricated a four-channel detector using four $3\times 3\times 3$ mm3 EJ-256 scintillators and Si-APD arrays of $3\times 3$ mm2 pixels to increase the detection efficiency. The detector had a 12-mm beam path in the EJ-256. Moreover, a 10wt% HfO2-nanoparticle-doped plastic scintillator (Hf-PLS), 3 mm in diameter and 1 mm in thickness, was examined using the prototype detector. Hafnium is a heavy atom of atomic number 72 and the energy of the K-absorption edge is 65.351 keV. Its oxide nanoparticles, ~4 nm in diameter, were incorporated into a polymer matrix. The pulse-height distribution and time spectra for the detector with the Hf-PLS were measured at −34 °C with an APD gain of ~200 for 57.6-keV X-rays. The light yield of the Hf-PLS was 1.2 times that of the EJ-256 of the same size, and a good time resolution of 0.34 ns (full width of half maximum) was obtained better than that of 0.54 ns for the EJ-256. This was due to the difference in the scintillation solution, as only 2-(4-tert-butylphenyl)-5-(4-phenylphenyl)-1,3, 4-oxadiazole was added in the Hf-PLS, however, for in the EJ-256, the binary solutions, such as 2,5-diphenyloxazole and 1,4-bis (5-phenyl- 2-oxazolyl)benzene, were included.
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Observation of 67 keV x-rays with a scintillation detector using Proportional-Mode silicon avalanche photodiode
2016Co-Authors: Keisuke Inoue, Shunji KishimotoAbstract:We developed a scintillation X-ray detector using a Proportional-Mode silicon avalanche photodiode (Si-APD). We report a prototype detector using a lead-loaded plastic scintillator mounted on a Proportional-Mode Si-APD (active area size: 3 mm in diameter), which is operated at a low temperature. Using 67.41 keV X-rays, we could measure pulse-height spectra of scintillation light with a charge-sensitive preamplifier at 20, 0, and −35°C. Time spectra of the X-ray bunch structure were successfully recorded using a wideband and 60-dB-gain amplifier in hybrid-Mode operation of the Photon Factory ring. We obtained a better time resolution of 0.51 ns (full width at half-maximum) for the single-bunch X-ray peak at −35°C. We were also able to observe a linear response of the scintillation pulses up to 8 Mcps for input photon rates up to 1.4 × 108 photons/s.
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Fast scintillation timing detector using Proportional-Mode avalanche photodiode for nuclear resonant scattering experiments in high-energy synchrotron X-ray region
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2016Co-Authors: Keisuke Inoue, Shunji KishimotoAbstract:Abstract To obtain both a high count rate of >10 7 s −1 and a detection efficiency sufficient for high-energy X-rays of >30 keV, we propose a scintillation timing detector using a Proportional-Mode silicon avalanche photodiode (Si-APD) for synchrotron radiation nuclear resonant scattering. We here present results obtained with a prototype detector using a lead-loaded plastic scintillator (EJ-256) mounted on a Proportional-Mode Si-APD (active area size: 3 mm in diameter). The detector was operated at ‒35 °C for a better signal-to-noise ratio. Using synchrotron X-rays of 67.41 keV, which is the same energy as the first excited level of 61 Ni, we successfully measured pulse-height and time spectra of the scintillation light. A good time resolution of 0.50±0.06 ns (full width at half-maximum) was obtained for 67.41 keV X-rays with a scintillator 3 mm in diameter and 2 mm thick.
Jean-claude Lefebvre - One of the best experts on this subject based on the ideXlab platform.
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Can Proportional ventilation Modes facilitate exercise in critically ill patients? A physiological cross-over study
Annals of Intensive Care, 2017Co-Authors: Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-christophe Marie Richard, Laurent BrochardAbstract:Background Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a Proportional Mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and Proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise. Methods Prospective pilot randomized cross-over study performed in a medico-surgical ICU. Patients requiring mechanical ventilation >48 h were enrolled. At initiation, the patients underwent an incremental workload test on a cycloergometer to determine the maximum level capacity. The next day, 2 15-min exercise, at 60% of the maximum capacity, were performed while patients were randomly ventilated with PSV and PAV+ or NAVA. The change in oxygen consumption (ΔVO_2, indirect calorimetry) and the work efficiency (ratio of ΔVO_2 per mean power) were computed. Results Ten patients were examined, 6 ventilated with PSV/PAV+ and 4 with PSV/NAVA. Despite the same mean inspiratory pressure at baseline between the Modes, baseline VO_2 (median, IQR) was higher during Proportional ventilation (301 ml/min, 270–342) compared to PSV (249 ml/min, 206–353). Exercise with PSV was associated with a significant increase in VO_2 (ΔVO_2, median, IQR) (77.6 ml/min, 59.9–96.5), while VO_2 did not significantly change during exercise with Proportional Modes (46.3 ml/min, 5.7–63.7, p
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Can Proportional ventilation Modes facilitate exercise in critically ill patients? A physiological cross-over study
Annals of intensive care, 2017Co-Authors: Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-christophe M. Richard, Laurent BrochardAbstract:Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a Proportional Mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and Proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise. Prospective pilot randomized cross-over study performed in a medico-surgical ICU. Patients requiring mechanical ventilation >48 h were enrolled. At initiation, the patients underwent an incremental workload test on a cycloergometer to determine the maximum level capacity. The next day, 2 15-min exercise, at 60% of the maximum capacity, were performed while patients were randomly ventilated with PSV and PAV+ or NAVA. The change in oxygen consumption (ΔVO2, indirect calorimetry) and the work efficiency (ratio of ΔVO2 per mean power) were computed. Ten patients were examined, 6 ventilated with PSV/PAV+ and 4 with PSV/NAVA. Despite the same mean inspiratory pressure at baseline between the Modes, baseline VO2 (median, IQR) was higher during Proportional ventilation (301 ml/min, 270–342) compared to PSV (249 ml/min, 206–353). Exercise with PSV was associated with a significant increase in VO2 (ΔVO2, median, IQR) (77.6 ml/min, 59.9–96.5), while VO2 did not significantly change during exercise with Proportional Modes (46.3 ml/min, 5.7–63.7, p
