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6. Erbium-doped aluminophosphosilicate all-fiber laser operating at 1584 nm

Author

Lord, Marie-Pier, Talbot, Lauris, Boily, Olivier, Boilard, Tommy, Gariépy, Guillaume, Grelet, Sacha, Paradis, Pascal, Grégoire, Nicolas, Morency, Steeve, Messaddeq, Younès, and Bernier, Martin

Subjects
Physics - Optics
Abstract

We report on an ytterbium-free erbium-doped aluminophosphosilicate all-fiber laser, producing an output power of 25 W at a wavelength of 1584 nm with a slope efficiency of 30% with respect to the 976 nm absorbed pump power. The simple cavity design proposed takes advantage of fiber Bragg gratings written directly in the gain fiber. The single-mode erbium-doped aluminophosphosilicate fiber was fabricated in-house and was doped with 0.06 mol.% of Er2O3, 1.77 mol.% of Al2O3 and 1.04 mol.% of P2O5. The incorporation of aluminium and phosphorus into the fiber core allowed for an increased concentration of erbium without inducing significant clustering, while keeping the numerical aperture low to ensure a single-mode laser operation.

Published
2019
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9. A physiologically based pharmacokinetic (PBPK) model exploring the blood-milk barrier in lactating species - A case study with oxytetracycline administered to dairy cows and goats

Author

Tardiveau, Jennifer, LeRoux-Pullen, Lerica, Gehring, Ronette, Touchais, Gaël, Chotard-Soutif, Marie Pierre, Mirfendereski, Hélène, Paraud, Carine, Jacobs, Matthieu, Magnier, Reynald, Laurentie, Michel, Couet, William, Marchand, Sandrine, Viel, Alexis, and Grégoire, Nicolas

Published
2022
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12. Pharmacokinetics of Polymyxins in Animals

Author

Marchand, Sandrine, Grégoire, Nicolas, Couet, William, COHEN, IRUN R., Editorial Board Member, LAJTHA, ABEL, Editorial Board Member, LAMBRIS, JOHN D., Editorial Board Member, PAOLETTI, RODOLFO, Editorial Board Member, REZAEI, NIMA, Editorial Board Member, Li, Jian, editor, Nation, Roger L., editor, and Kaye, Keith S., editor

Published
2019
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17. Pharmacokinetic/pharmacodynamic analysis of ceftazidime/avibactam and fosfomycin combinations in an in vitro hollow fiber infection model against multidrug-resistant Escherichia coli

Author

Kroemer, Niklas, primary, Amann, Lisa F., additional, Farooq, Aneeq, additional, Pfaffendorf, Christoph, additional, Martens, Miklas, additional, Decousser, Jean-Winoc, additional, Grégoire, Nicolas, additional, Nordmann, Patrice, additional, and Wicha, Sebastian G., additional

Published
2023
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18. An improved PKPD modeling approach to characterize the pharmacodynamic interaction over time between ceftazidime/avibactam and colistin from in vitro time-kill experiments against multidrug-resistant Klebsiella pneumoniae isolates

Author

Aubry, Romain, primary, Buyck, Julien, additional, Prouvensier, Laure, additional, Decousser, Jean-Winoc, additional, Nordmann, Patrice, additional, Wicha, Sebastian G., additional, Marchand, Sandrine, additional, and Grégoire, Nicolas, additional

Published
2023
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19. Characterization of Pseudomonas aeruginosa resistance to ceftolozane-tazobactam due to ampC and/or ampD mutations observed during treatment using semi-mechanistic PKPD modeling

Author

Deroche, Luc, primary, Aranzana-Climent, Vincent, additional, Rozenholc, Albane, additional, Prouvensier, Laure, additional, Darnaud, Léa, additional, Grégoire, Nicolas, additional, Marchand, Sandrine, additional, Ploy, Marie-Cécile, additional, François, Bruno, additional, Couet, William, additional, Barraud, Olivier, additional, and Buyck, Julien M., additional

Published
2023
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24. Baria-silica erbium-doped fibers for extended L-band amplification

Author

Jalilpiran, Saber, Fuertes, Victor, Lefebvre, Jacques, Grégoire, Nicolas, Durak, Firat, Landry, Nelson, Wang, Lixian, Rivera, V. A. G, Messaddeq, Younès, LaRochelle, Sophie, Jalilpiran, Saber, Fuertes, Victor, Lefebvre, Jacques, Grégoire, Nicolas, Durak, Firat, Landry, Nelson, Wang, Lixian, Rivera, V. A. G, Messaddeq, Younès, and LaRochelle, Sophie

Abstract

We present baria-silica erbium-doped fibers (BaEDF) for extending the bandwidth of L-band EDFAs beyond 1620 nm. Using a combination of modified chemical vapor deposition (MCVD) process and solution-doping technique, we demonstrate low loss (<10 dB/km at 1200 nm) fiber cores with BaO concentration of 1-3 mol% and Er3+ concentration of 8×1024 m-3 . We show that the optical properties and EDFA performance are positively affected by increasing the BaO content. Namely, when we increase the BaO concentration from 1.3 to 3 mol%, we observe a reduction of pair-induced quenching that correlates with a biexponential luminescence decay with a dominant 15.5 ms lifetime component. Furthermore, the slight modifications of absorption/ emission coefficients point to a red-shift of the signal excited state absorption and consequently, to a moderate extension of the L-band gain to longer wavelengths (1622 nm).

Published
2023

33. Pharmaco-toxico : a very bad trip ?

Author

Oualha, Mehdi, primary, Tournier, Nicolas, additional, Préau, Sébastien, additional, Grégoire, Nicolas, additional, Voiriot, Guillaume, additional, Pierre, Alexandre, additional, Joffre, Jérémie, additional, Gaudet, Alexandre, additional, Jouan, Youenn, additional, Kallel, Hatem, additional, Radermacher, Peter, additional, Sarton, Benjamine, additional, Stiel, Laure, additional, Bréchot, Nicolas, additional, Lemaitre, Florian, additional, Vodovar, Dominique, additional, CRT, De la SRLF, additional, and SFPT, Partenaire, additional

Published
2022
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36. Tunable distributed sensing performance in Ca-based nanoparticle-doped optical fibers

Author

Fuertes, Victor, Grégoire, Nicolas, Morency, Steeve, Gagnon, Stéphane, Ledemi, Yannick, LaRochelle, Sophie, Messaddeq, Younès, Fuertes, Victor, Grégoire, Nicolas, Morency, Steeve, Gagnon, Stéphane, Ledemi, Yannick, LaRochelle, Sophie, and Messaddeq, Younès

Abstract

Rayleigh scattering enhanced nanoparticle-doped optical fibers is a technology very promising for distributed sensing applications, however, it remains largely unexplored. This work demonstrates for the first time the possibility of tuning Rayleigh scattering and optical losses in Ca-based nanoparticle-doped silica optical fibers by controlling the kinetics of the re-nucleation process that nanoparticles undergo during fiber drawing by controlling preform feed, drawing speed and temperature. A 3D study by SEM, FIB-SEM and optical backscatter reflectometry (OBR) reveals an early-time kinetics at 1870 °C, with tunable Rayleigh scattering enhancement 43.2–47.4 dB, regarding a long-haul single mode fiber, SMF-28, and associated sensing lengths of 3–5.5 m. At 2065 °C, kinetics is slower and nanoparticle dissolution is favored. Consequently, enhanced scattering values of 24.9–26.9 dB/m and sensing lengths of 135–250 m are attained. Finally, thermal stability above 500 °C and tunable distributed temperature sensitivity are proved, from 18.6 pm/°C to 23.9 pm/°C, ∼1.9–2.4 times larger than in a SMF-28. These results show the promising future of Rayleigh scattering enhanced nanoparticle-doped optical fibers for distributed sensing.

Published
2022

37. Tunable distributed sensing performance in Ca-based nanoparticle-doped optical fibers

Author

Gagnon, Stéphane, Grégoire, Nicolas, Morency, Steeve, Ledemi, Yannick, Fuertes, Victor, LaRochelle, Sophie, Messaddeq, Younès, Gagnon, Stéphane, Grégoire, Nicolas, Morency, Steeve, Ledemi, Yannick, Fuertes, Victor, LaRochelle, Sophie, and Messaddeq, Younès

Abstract

Rayleigh scattering enhanced nanoparticle-doped optical fibers is a technology very promising for distributed sensing applications, however, it remains largely unexplored. This work demonstrates for the first time the possibility of tuning Rayleigh scattering and optical losses in Ca-based nanoparticle-doped silica optical fibers by controlling the kinetics of the re-nucleation process that nanoparticles undergo during fiber drawing by controlling preform feed, drawing speed and temperature. A 3D study by SEM, FIB-SEM and optical backscatter reflectometry (OBR) reveals an early-time kinetics at 1870 °C, with tunable Rayleigh scattering enhancement 43.2–47.4 dB, regarding a long-haul single mode fiber, SMF-28, and associated sensing lengths of 3–5.5 m. At 2065 °C, kinetics is slower and nanoparticle dissolution is favored. Consequently, enhanced scattering values of 24.9–26.9 dB/m and sensing lengths of 135–250 m are attained. Finally, thermal stability above 500 °C and tunable distributed temperature sensitivity are proved, from 18.6 pm/°C to 23.9 pm/°C, ∼1.9–2.4 times larger than in a SMF-28. These results show the promising future of Rayleigh scattering enhanced nanoparticle-doped optical fibers for distributed sensing.

Published
2022

39. Controlled phase-separation effect for enhanced optical refrigeration in yttrium-aluminosilicate glasses.

Author

Meyneng, Thomas, Thomas, Jyothis, Grégoire, Nicolas, Leelapornpisit, Weawkamol, Valdez, Jesus, Kashyap, Raman, and Messaddeq, Younεave;s

Abstract

Silica glass is one of the most commonly used photonic materials. Fabrication through vapor deposition allows the large production of high-quality bulk and optical fibers, widely employed in light guidance and amplification. Recent research on optical refrigeration of ytterbium-doped silicate has drawn attention to its potential, demonstrating near-unity quantum yields with optical refrigeration measurements in both preforms and fibers. However, the low solubility of lanthanide and the high-phonon environment of a SiO2 network poses limitations on material performance. In our study, Yb-doped yttrium-aluminosilicate (YAS) glasses were fabricated by a modified chemical vapor deposition process. The high concentration of rare-earth elements (Y + Yb) led to a phase separation effect visible only at the nanometer scale. Spherical amorphous domains showed elevated amounts of yttrium, aluminum, and ytterbium in contrast with the surrounding matrix. This unique feature significantly reduced the concentration quenching effects, even at a Yb density higher than 1026 ions per cubic meter, while promoting a low-phonon environment. Yb-doped yttrium-aluminosilicate samples with varying Yb density presented near-unity external quantum efficiencies, enabling optical refrigeration up to −2.4 K starting from room temperature under atmospheric pressure. [ABSTRACT FROM AUTHOR]

Published
2023
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44. Cubic-Shaped and Rod-Shaped YPO4 Nanocrystal-Doped Optical Fibers: Implications for Next Generation of Fiber Lasers.

Author

Fuertes, Victor, Grégoire, Nicolas, Labranche, Philippe, Gagnon, Stéphane, Hamada, Natalie, Bellanger, Brice, Ledemi, Yannick, LaRochelle, Sophie, and Messaddeq, Younès

Abstract

Engineering silica optical fibers by nanoparticle doping is a promising technology that allows the introduction of new functionalities and extends their applicable fields. However, the knowledge gap about the impact of the extreme fabrication temperatures on the nanoparticle features prevents field progress. Herein, we demonstrate that the particularities of fiber fabrication, such as fast-heating rates and quenching heat treatments, can be leveraged to explore unlikely phenomena at the nanoscale under standard laboratory conditions. Tetragonal cubic-shaped and monoclinic rod-shaped YPO4 nanocrystals are in situ nucleated in a silica-based fiber core glass, slightly modified with Ge and P, which shows for the first time, the possibility of doping optical fibers with this type of nanostructures, in terms of shape, composition, and structure of the nanocrystals. Structural and anisotropic differences allow engineering differently their shape and composition in the fiber core by tailoring the drawing temperature, as revealed by a thorough study consisting of scanning electron microscopy (SEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), electron energy loss spectroscopy (EELS), and high-resolution transmission electron microscopy (HRTEM). This work demonstrates, for the first time, the possibility of doping optical fibers fabricated by modified chemical vapor deposition (MCVD) with anisotropic nanostructures, as well as the stability of the monoclinic YPO4 phase. These findings open up new avenues to study shape-dependent properties of rare-earth orthophosphate (REPO4) nanostructures in optical fibers which will allow incorporating unprecedented functionalities and will have an impact in several fields of application, such as fiber lasers and optical fiber amplifiers, among others. [ABSTRACT FROM AUTHOR]

Published
2023
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46. Functionalization of Mono- and Bimetallic MIL-100(Al,Fe) MOFs by Ethylenediamine: Postfunctionalization, Brønsted Acido-Basicity, and Unusual CO2 Sorption Behavior

Author

Steenhaut, Timothy, primary, Fusaro, Luca, additional, Robeyns, Koen, additional, Lacour, Séraphin, additional, Li, Xiao, additional, Mahy, Julien G., additional, Louppe, Véronique, additional, Grégoire, Nicolas, additional, Barozzino-Consiglio, Gabriella, additional, Statsyns, Jean-François, additional, Aprile, Carmela, additional, Filinchuk, Yaroslav, additional, and Hermans, Sophie, additional

Published
2021
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48. Functionalization of mono- and bimetallic MIL-100(Al,Fe) MOFs by ethylenediamine: post-functionalization, Brønsted acido-basicity and unique CO2 sorption behaviour

Author

Steenhaut, Timothy, primary, Fusaro, Luca, additional, Robeyns, Koen, additional, Lacour, Séraphin, additional, Li, Xiao, additional, Mahy, Julien G., additional, Louppe, Véronique, additional, Grégoire, Nicolas, additional, Barozzino-Consiglio, Gabriella, additional, Statsijns, Jean-François, additional, Aprile, Carmela, additional, Filinchuk, Yaroslav, additional, and Hermans, Sophie, additional

Published
2021
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49. Subcutaneous Antibiotic Therapy: The Why, How, Which Drugs and When

Author

Hernández-Ruiz, Virgilio, Forestier, Emmanuel, Gavazzi, Gaëtan, Ferry, Tristan, Grégoire, Nicolas, Breilh, Dominique, Paccalin, Marc, Goutelle, Sylvain, Roubaud-Baudron, Claire, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán - National Institute of Medical Science and Nutrition Salvador Zubiran [Mexico], CHU Bordeaux [Bordeaux], Centre Hospitalier Métropole Savoie [Chambéry], Groupe de Recherche et d'Etude du Processus Inflammatoire (GREPI), 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 Grenoble Alpes (UGA), CHU Grenoble, Hospices Civils de Lyon (HCL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon, Centre hospitalier universitaire de Poitiers (CHU Poitiers), Pharmacologie des anti-infectieux et antibiorésistance (PHAR2), Université de Poitiers-Institut National de la Santé et de la Recherche Médicale (INSERM), Biologie des maladies cardiovasculaires = Biology of Cardiovascular Diseases, Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), CIC - Poitiers, Université de Poitiers-Centre hospitalier universitaire de Poitiers (CHU Poitiers)-Direction Générale de l'Organisation des Soins (DGOS)-Institut National de la Santé et de la Recherche Médicale (INSERM), HCL Groupement Hospitalier Nord [Lyon], Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), 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), Bordeaux Research In Translational Oncology [Bordeaux] (BaRITOn), Université de Bordeaux (UB)-CHU Bordeaux [Bordeaux]-Institut National de la Santé et de la Recherche Médicale (INSERM), and CCSD, Accord Elsevier

Subjects
[SDV.MHEP] Life Sciences [q-bio]/Human health and pathology, Subcutaneous, subcutaneously administered, antibiotics, antimicrobials, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience; To describe the rationale for subcutaneous (SC) administration of antibiotics from available published data and to make propositions to help clinicians in daily practice. Narrative review. Hospitalized patients, persons in long-term care facilities and ambulatory care. We searched the MEDLINE/PubMed electronic database for evidence supporting SC administration of antibiotics up to September 2019; the results of this primary search were supplemented by searching the references of the identified articles, as well as by searching in Google Scholar. Regarding tolerability, efficacy, and pharmacokinetic/pharmacodynamic profiles, most studies suggest that the SC route could be an alternative to the intravenous route, particularly for time-dependent antibiotics and among certain patient populations, such as patients with poor venous access, swallowing disorders, or behavioral disturbance. However, clinical evidence of the benefits and risks of SC antibiotic administration is still scarce and of low level. SC administration of antibiotics may be useful in various settings such as in hospitalized patients and among those in long-term care facilities or being cared for at home. However, further clinical studies are needed to assess the pharmacokinetic/pharmacodynamic properties, as well as the risks and benefits of SC administration of antibiotics. In this review, we highlight the potential benefits of SC administration of antibiotics and address practical recommendations for its use. This information will enable improvement of treatment strategies and present the SC route as a potential option in specific situations.

Published
2021
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