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Murviel-lès-Montpellier, France

Shalaby B.M.,CNRS XLIM Research Institute, Limoges | Shalaby B.M.,Tanta University | Labruyere A.,CNRS XLIM Research Institute, Limoges | Krupa K.,CNRS XLIM Research Institute, Limoges | And 4 more authors.
Optical Sensors, 2014 | Year: 2014

We present an experimental study of supercontinuum generation for applications in flow cytometry in a rectangular-core multimode microstructured optical fiber pumped at 532nm. We generated a bright visible supercontinuum spectrum spanning from 350 nm to 1080 nm. © 2014 OSA.

Andreana M.,University of Limoges | Bertrand A.,Multitel A.s.b.l. | Hernandez Y.,Multitel A.s.b.l. | Leproux P.,University of Limoges | And 8 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

This paper introduces a supercontinuum (SC) laser source emitting from 400 nm to beyond 1750 nm, with adjustable pulse repetition rate (from 250 kHz to 1 MHz) and duration (from ∼200 ps to ∼2 ns). This device makes use of an internally-modulated 1.06 μm semiconductor laser diode as pump source. The output radiation is then amplified through a preamplifier (based on single-mode Yb-doped fibres) followed by a booster (based on a double-clad Yb-doped fibre). The double-clad fibre output is then spliced to an air-silica microstructured optical fibre (MOF). The small core diameter of the double-clad fibre allows reducing the splice loss. The strongly nonlinear propagation regime in the MOF leads to the generation of a SC extending from the violet to the near-infrared wavelengths. On the Stokes side of the 1.06 μm pump line, i.e., in the anomalous dispersion regime, the spectrum is composed of an incoherent distribution of quasi-solitonic components. Therefore, the SC source is characterised by a low coherence length, which can be tuned by simply modifying pulse duration, that is closely related to the number of quasi-solitonic components brought into play. Finally, the internal modulation of the laser diode permits to achieve excellent temporal stability, both in terms of average power and pulse-to-pulse period. © 2010 SPIE.

Isebe D.,HORIBA Medical | Nerin P.,HORIBA Medical
International Journal for Numerical Methods in Biomedical Engineering | Year: 2013

This paper describes how to numerically tackle the problem of counting and sizing particles by impedance measurement in an orifice-electrode system. The model allows to simulate the particle dynamics submitted to strong hydrodynamic stresses through a microorifice and to compute the voltage pulses generated by the modification of the inner dielectric medium. This approach gives important information about particles size distribution and allows to quantify the role of trajectory and orientation of particles on the size measurement. Copyright © 2012 John Wiley & Sons, Ltd. In most cases, counting and sizing of biological cells are based on electrical gating through a microorifice in a close orifice-electrode system that we don't experimentally apprehend. In this framework, we have developed a complete numerical approach to compute the exact particle size distribution by taking into account the trajectory and the orientation of the particles through the microorifice. This numerical approach is fully innovative in diagnosis engineering and can be used to perform particle sizing measurement by optimizing shape design or fluidic conditions. © 2012 John Wiley & Sons, Ltd.

Pierelli L.,University of Rome La Sapienza | Fioravanti D.,San Camillo Forlanini Hospital | Patti D.,HORIBA Medical | Iudicone P.,San Camillo Forlanini Hospital | And 3 more authors.
International Journal of Laboratory Hematology | Year: 2012

Introduction: Accurate white blood cell counting (WBC) and differential count by blood analyzers could allow a more informative characterization of granulocyte colony-stimulating factor (G-CSF) mobilized blood (MB), leukapheresis products (LP), and cord blood (CB). However, reliable counting by a blood cell analyzer in this setting is a major challenge owing to quali-quantitative abnormalities of blood cells. Methods: We evaluated the performances of the analyzer Pentra DX 120 by Horiba ABX working with dedicated cell-gating profiles, which generate three-part differential counts in samples obtained from donors' MB, LP, and CB. The results of the analyzer were compared to counts obtained by flow cytometry and manual counts, the latter performed for reference validation and in the case of discrepant results between study and reference counts. Results: Pentra DX 120 generated highly correlated counts (R>0.91 in all cases) to those obtained by flow cytometry in all samples (MB, LP, and CB) with high degree of count accuracy in most cases and referred to WBC absolute count and differential count including lymphocytes (LYM) %, monocytes (MON) %, and polymorphonuclear leukocytes (PMN) %. Accuracy, judged by the difference between study and reference counts and expressed as percentage of reference count, ranged from 0.8% to 8.6%, and sporadic loss of accuracy occurred for MON % only in no more than 10% of CB samples. Conclusion: The ABX Pentra DX 120 provided accurate WBC count and differential count during MB, LP, and CB analyses and allowed a better characterization of donors' hematologic status and graft composition. © 2011 Blackwell Publishing Ltd.

Rongeat N.,HORIBA Medical | Brunel P.,HORIBA Medical | Gineys J.-P.,HORIBA Medical | Cremien D.,HORIBA Medical | And 2 more authors.
Optics Express | Year: 2011

The aim of this study is to combine multiple excitation wavelengths in order to improve accuracy of fluorescence characterization of labeled cells. The experimental demonstration is realized with a hematology analyzer based on flow cytometry and a CW laser source emitting two visible wavelengths. A given optical encoding associated to each wavelength allows fluorescence identification coming from specific fluorochromes and avoiding the use of noisy compensation method. © 2011 Optical Society of America.

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