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Registros recuperados: 27 | |
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Wacquet, Guillaume; Grosjean, Philippe; Colas, Florent; Hamad, Denis; Artigas, Luis Felipe. |
The coupled system FlowCAM/ZooPhytoImage has become a real operational tool in 2014. However, to be fully adapted to the observations of phytoplankton performed in the context of the REPHY observation network and in order to better respond to present and future requests concerning the evaluation of quality of coastal and marine waters within the European requirements, such as the WFD and MSFD, new functionalities must be integrated into existing tools. Therefore, different axis of development have been proposed by UMONS and Ifremer to adapt both the digitization device and the Zoo/PhytoImage software to the constraints defined by the REPHY. First, version 5 of Zoo/PhytoImage contains recent innovations such as the development of routines to automatically... |
Tipo: Text |
Palavras-chave: Plancton; Analyse automatisée; Analyse d'image; Classification supervisée; Apprentissage actif; Dénombrement de cellules; Plankton; Automated analysis; Image processing; Supervised classification; Active learning; Cells counting. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00389/49986/50573.pdf |
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Colas, Florent; Laurent, Sebastien; Lehaitre, Michel; Hamelin, Muriel; Crassous, Marie-pierre; Antoine, Elisabeth; Dreanno, Catherine; Deuff, Albert; Compere, Chantal. |
For the last few years there is a more and more pressing need to develop system for detecting HAB at their early stage. Researchers have then been working on new in situ sensor. In this paper a submarine transducer based on surface plasmon resonance is reported. It demonstrated a refractive index resolution of 3.10(-6), which is promising for later phytoplankton detection. |
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Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00107/21802/20328.pdf |
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Colas, Florent; Tardivel, Morgan; Evrard, Justine; Forest, Bertrand; Crassous, Marie-pierre; Lunven, Michel; Danielou, Marie-madeleine. |
This deliverable contains all development work of the FastCAM, new tool for fast imaging of the phytoplankton, which took place in 2015. It consists of: One report of the FastCAM and its comparison with the FlowCAM presentation: The FlowCAM enables the digitalization of a sample of phytoplankton with X10 and X 4 magnifications. The first allows a better morphological description and therefore a higher taxonomic resolution but with a longer scan time (16 X). Thus, for routine analyses, only scanning at 4 X is possible. A considerable gain would be able to do an acquisition to the magnification 10 X with a time of analysis more short, comparable to 4 X. A fast flow imaging system has therefore developed in this sense. He was called FastCAM. The system is... |
Tipo: Text |
Palavras-chave: FlowCAM; FastCAM; Imagerie rapide; Phytoplancton; REPHY.; FlowCAM; FastCAM; Fast imaging; Phytoplankton; REPHY. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00363/47420/47425.pdf |
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Anne, Marie-laure; Keirsse, Julie; Nazabal, Virginie; Hyodo, Koji; Inoue, Satoru; Boussard-pledel, Catherine; Lhermite, Herve; Charrier, Joel; Yanakata, Kiyoyuki; Loreal, Olivier; Le Person, Jenny; Colas, Florent; Compere, Chantal; Bureau, Bruno. |
Due to the remarkable properties of chalcogenide (Chg) glasses, Chg optical waveguides should play a significant role in the development of optical biosensors. This paper describes the fabrication and properties of chalcogenide fibres and planar waveguides. Using optical fibre transparent in the mid-infrared spectral range we have developed a biosensor that can collect information on whole metabolism alterations, rapidly and in situ. Thanks to this sensor it is possible to collect infrared spectra by remote spectroscopy, by simple contact with the sample. In this way, we tried to determine spectral modifications due, on the one hand, to cerebral metabolism alterations caused by a transient focal ischemia in the rat brain and, in the other hand, starvation... |
Tipo: Text |
Palavras-chave: Planar waveguide; Fibre; Optical sensor; Chalcogenide. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6851.pdf |
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Laurent, Sebastien; Colas, Florent; Hamelin, Muriel; Crassous, Marie-pierre; Antoine, Elisabeth; Lehaitre, Michel; Compere, Chantal. |
Among marine algae species, Alexandrium minutum produces a phycotoxin called paralytic shellfish poisoning (PSP) that is introduced in the food chain through the ingestion of phytoplankton by shellfishs, and later by human consumers. Thus, in situ monitoring of A. minutum proliferation in coastal seawater is of great economical importance for marine resources exploitation. Here, we propose a rapid test for the detection of A. minutum by surface plasmon resonance spectroscopy. First, whole genomic DNA is extracted from the algae. Second, a 677 bp long portion of the 28S ribosomal DNA is amplified by PCR. Third, the PCR product is detected by surface plasmon resonance spectroscopy onto a DNA functionalized gold substrate. |
Tipo: Text |
Palavras-chave: PCR; Algal detection; In situ; Spectroscopy; Surface plasmon resonance. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6830.pdf |
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Dridi, Montacer; Colas, Florent; Compere, Chantal. |
For the last few years, plasmon-based lasers have been investigated theoretically and experimentally. Several configurations have been reported. They are composed of quantum emitters coupled to a plasmonic structure. In this paper, we investigate the effect of the plasmon mode on the far-field and near-field characteristics of a nanolaser composed by a periodic array of metallic nanoparticles covered by gain materials under optical pumping. Two configurations were investigated. The first structure supported a localized surface plasmon (LSP) mode, while the second a surface lattice plasmon (SLP) mode. This theoretical work relies on semi-quantum calculations based on a four-level gain molecule and a time-domain approach. We demonstrated that lasing in a SLP... |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00473/58490/61054.pdf |
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Wacquet, Guillaume; Lefebvre, Alain; Colas, Florent; Grosjean, Philippe. |
Today, the most widely used method for the analysis of samples within the REPHY network, is the microscopy. However, this method has several drawbacks: different skill level depending on the analyst, taxa may be misidentified, analyst subject to fatigue and loss of concentration, non-quantifiable errors. That is why different axis of development have been proposed to adapt the FlowCAM and ZooPhytoImage to the requirements of REPHY network which are the accuracy and repeatability of the measurement. The purpose of these new tools being to provide a tangible gain of time for analysts compared to the observations with optical microscope. The analysis time being a key point of this system, studies were conducted in order to achieve a fast acquisition. To have... |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00363/47440/47465.pdf |
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Verger, F.; Pain, T.; Nazabal, V.; Boussard-pledel, C.; Bureau, Bruno; Colas, Florent; Rinnert, Emmanuel; Boukerma, Kada; Compere, Chantal; Guilloux-viry, M.; Deputier, S.; Perrin, A.; Guin, J. P.. |
The development of infrared sensing platform requires adapted materials. In this work, we used sputtered gold nanoparticles on a chalcogenide glass to demonstrate that these infrared materials can be used as substrate for surface enhanced infrared absorption (SEIRA) spectroscopy. The sputtering parameters were optimized to get the highest possible enhancement. To assess it, a self-assembled monolayer of 4-nitrothiophenol was used. These preliminary results are promising and pave the way for various configurations of waveguide for integrated optical components. (C) 2012 Elsevier B.V. All rights reserved. |
Tipo: Text |
Palavras-chave: Chalcogenide glass; Sputtering; Gold nanoparticles; 4-Nitrothiophenol; SEIRA; Surface enhanced infrared absorption. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00116/22748/20613.pdf |
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Boccadoro, Catherine; Karlson, Bengt; Colas, Florent. |
The aim of Task 3.4 was to develop and test innovative methods for the molecular detection of phytoplankton, harmful algal blooms and pollutants through their effect on microbial communities. This included the development of novel molecular sensors for the detection, quantification and identification of organisms, microbial markers of pollutant exposure or toxin concentrations in marine coastal waters. Bacterial species and genes which can be used as markers of high nutrient load or hydrocarbon contamination in the marine environment were identified through bacterial community analysis in contaminated environments and literature reviews. Assays using quantitative Polymerase Chain Reaction (qPCR) for the quantification of these organisms were developed and... |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00630/74246/73876.pdf |
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Colas, Florent; Crassous, Marie-pierre; Laurent, Sebastien; Litaker, Richard W.; Rinnert, Emmanuel; Le Gall, Erwan; Lunven, Michel; Delauney, Laurent; Compère, Chantal. |
Over the past decade Surface Plasmon Resonance (SPR) techniques have been applied to the measurement of numerous analytes. In this article, an SPR biosensor system deployed from an oceanographic vessel was used to measure dissolved domoic acid (DA), a common and harmful phycotoxin produced by certain microalgae species belonging to the genus Pseudo-nitzschia. During the biosensor deployment, concentrations of Pseudo-nitzschia cells were very low over the study area and measured DA concentrations were below detection. However, the in situ operational detection limit of the system was established using calibrated seawater solutions spiked with DA. The system could detect the toxin at concentrations as low as 0.1 ng mL−1 and presented a linear dynamic range... |
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Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00324/43481/42921.pdf |
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Dribek, Mohamed; Rinnert, Emmanuel; Colas, Florent; Crassous, Marie-pierre; Thioune, Nene; David, Catalina; De La Chapelle, Marc; Compere, Chantal. |
We demonstrated the use of a new organometallic nanoprobe for competitive surface-enhanced Raman scattering (SERS) immunoassay devoted to the detection of polycyclic aromatic hydrocarbons (PAH) such as benzo[a]pyrene (BaP) in seawater. The nanoprobes are gold nanoparticles (GNPs) labeled by a Raman reporter, the 5,5'-dithiobis(succinimidyl-2-nitrobenzoate) (DSNB) and functionalized with monoclonal antibodies anti-BaP. The antibodies are bound with a high specificity to the analyte while the GNPs enhanced the Raman scattering of the DSNB. This type of immunoassay involved the grafting of BaP onto a sensing surface. Thus, NH2-terminated self-assembled monolayer is formed on the surface of gold substrate using cysteamine. Amines finally reacted with... |
Tipo: Text |
Palavras-chave: Biosensor; Surface-enhanced Raman scattering; Polycyclic aromatic hydrocarbons; Benzo[a]pyrene antibody; Organometallic nanoprobe. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00417/52844/53870.pdf |
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Colas, Florent; Cottat, Maximilien; Gillibert, Raymond; Guillot, Nicolas; Djaker, Nadia; Lidgi-guigui, Nathalie; Toury, Timothee; Barchiesi, Dominique; Toma, Andrea; Di Fabrizio, Enzo; Gucciardi, Pietro G.; De La Chapelle, Marc Lamy. |
Optimum amplification in Surface Enhanced Raman Scattering (SERS) from individual nanoantennas is expected when the excitation is slightly blue-shifted with respect to the Localized Surface Plasmon Resonance (LSPR), so that the LSPR peak falls in the middle between the laser and the Stokes Raman emission. Recent experiments have shown when moving the excitation from the visible to the near-infrared that this rule of thumb is no more valid. The excitation has to be red-shifted with respect to the LSPR peak, up to 80nm, to obtain highest SERS. Such discrepancy is usually attributed to a Near-Field (NF) to Far-Field (FF) spectral shift. Here we critically discuss this hypothesis for the case of gold nanocylinders. By combining multi-wavelength excitation SERS... |
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Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00341/45234/44668.pdf |
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Tijunelyte, I.; Guenin, E.; Lidgi-guigui, N.; Colas, Florent; Ibrahim, J.; Toury, T.; Lamy De La Chapelle, M.. |
Nanoplasmonics is a growing field of optical condensed matter science dedicated to optical phenomena at the nanoscale level in metal systems. Extensive research on noble metallic nanoparticles (NPs) has emerged within the last two decades due to their ability to keep the optical energy concentrated in the vicinity of NPs, in particular, the ability to create optical near-field enhancement followed by heat generation. We have exploited these properties in order to induce a localised “click” reaction in the vicinity of gold nanostructures under unfavourable experimental conditions. We demonstrate that this reaction can be controlled by the plasmonic properties of the nanostructures and we propose two physical mechanisms to interpret the observed plasmonic... |
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Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00368/47954/48018.pdf |
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Le Person, Jenny; Colas, Florent; Compere, Chantal; Lehaitre, Michel; Anne, M; Boussard Pledel, C; Bureau, B; Adam, J; Deputier, S; Guilloux Viry, M. |
The surface plasmon resonance phenomenon has been studied in a chalcogenide glass-based optical system. IR transmission properties of these materials combined to their high refractive indices lead to advantageous properties for sensing. In this study, numerical simulations have been carried out to investigate the potentialities of sulfide glass from the GeGaSbS system as a coupling prism material. Then, an angular modulation SPR biosensor has been set up in the Kretschmann-Raether arrangement. Experimental data are consistent with numerical calculation and the detection limit of the sensor is 3 x 10(-5) RIU. These preliminary results are promising. Further investigations have to be carried out to confirm the great potentialities of those materials for... |
Tipo: Text |
Palavras-chave: Infrared; Biosensor; Surface plasmon resonance; Chalcogenide glass. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3955.pdf |
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Verger, F.; Nazabal, V.; Colas, Florent; Nemec, P.; Cardinaud, C.; Baudet, E.; Chahal, R.; Rinnert, Emmanuel; Boukerma, Kada; Peron, Isabelle; Deputier, S.; Guilloux-viry, M.; Guin, J. P.; Lhermite, H.; Moreac, A.; Compere, Chantal; Bureau, Bruno. |
The primary objective of this study is the development of transparent thin film materials in the IR enabling strong infrared absorption of organic compounds in the vicinity of metal nanoparticles by the surface plasmon effect. For developing these optical micro-sensors, hetero-structures combining gold nanoparticles and chalcogenide planar waveguides are fabricated and adequately characterized. Single As2S3 and Ge25Sb10Se65 amorphous chalcogenide thin films are prepared by radio-frequency magnetron sputtering. For the fabrication of gold nanoparticles on a chalcogenide planar waveguide, direct current sputtering is employed. Fabricated single layers or hetero-structures are characterized using various techniques to investigate the influence of deposition... |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00170/28094/26679.pdf |
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Registros recuperados: 27 | |
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