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In this technical note, we present an advanced thermospectroscopic imager based on a Fourier transform infrared (FT-IR) spectrometer and a thermal camera. This new instrument can image both thermal emission and multispectral absorbance fields in a few seconds at a resolution of 4 cm−1 or less. The setup is made of a commercial FT-IR spectrometer (ThermoFisher Nicolet iS50R) synchronized to an IR camera (indium antimonide and strained layer superlattice) as a detector to record the interferograms in each pixel of the images. A fast Fourier transform algorithm with apodization and Mertz phase correction is applied to the images, and the background is rationed to process the interferograms into the absorbance spectra in each pixel. The setup and image processing are validated using thin polystyrene films; during this processing, more than 1750 spectra per second are recorded. A spectral resolution equivalent to that of commercial FT-IR spectrometers is obtained for absorbance peaks valued less than two. The transient capability of the FT-IR thermospectroscopic imager is illustrated by measuring the heterogeneous thermal and absorbance fields during the phase change of paraffin over a few minutes. The complete mechanism of the thermochemical processes during a polymer solidification is revealed through the thermospectroscopic images, demonstrating the usefulness of such an instrument in studying fast transient thermal and chemical phenomena with an improved spectral resolution.

For the first time, a standard rapid-scan Fourier-transform infrared (FT-IR) spectrometer was coupled with quantum cascade lasers (QCLs) tunable within the 1876–905 cm–1 spectral range, within one single setup, by keeping one single sample compartment. The aim was to extend the time resolution of absorption measurements by several orders of magnitude thanks to the fast pulsed QCL technology without losing the spectral information provided by standard FT-IR spectroscopy, both probing the same sample. By slightly modifying the optical bench arrangement, the spectrometer now enables a fast and easy switch between the standard FT-IR mode, used for classical broadband scans from 6000 to 650 cm–1, and the new QCL-irradiation mode, used for ultrafast recording at specific wavenumbers (the two diagnostics have superimposed beam paths). So, one can study a sample (in condensed or gaseous state) during a physical or chemical transformation first as a whole in a broadband configuration and then immediately switch to...

Time-gated F&ouml, rster resonance energy transfer (TG-FRET) between Tb complexes and luminescent semiconductor quantum dots (QDs) provides highly advantageous photophysical properties for multiplexed biosensing. Multiplexed Tb-to-QD FRET immunoassays possess a large potential for in vitro diagnostics, but their performance is often insufficient for their application under clinical conditions. Here, we developed a homogeneous TG-FRET immunoassay for the quantification of carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and prostate-specific antigen (PSA) from a single serum sample by multiplexed Tb-to-QD FRET. Tb&ndash, IgG antibody donor conjugates were combined with compact QD-F(ab&rsquo, )2 antibody acceptor conjugates with three different QDs emitting at 605, 650, and 705 nm. Upon antibody&ndash, antigen&ndash, antibody sandwich complex formation, the QD acceptors were sensitized via FRET from Tb, and the FRET ratios of QD and Tb TG luminescence intensities increased specifically with increasing antigen concentrations. Although limits of detection (LoDs: 3.6 ng/mL CEA, 3.5 ng/mL NSE, and 0.3 ng/mL PSA) for the triplexed assay were slightly higher compared to the single-antigen assays, they were still in a clinically relevant concentration range and could be quantified in 50 &micro, L serum samples on a B&middot, R&middot, A&middot, H&middot, M&middot, S KRYPTOR Compact PLUS clinical immunoassay plate reader. The simultaneous quantification of CEA, NSE, and PSA at different concentrations from the same serum sample demonstrated actual multiplexing Tb-to-QD FRET immunoassays and the potential of this technology for translation into clinical diagnostics.

Background Severe allergy to fruits mediated by a 7 kDa allergen belonging to the gibberellin-regulated protein (GRP) family is known to be associated with Cupressaceae pollinosis. Objective To identify and characterize Cupressaceae pollen allergens involved in GRP-related fruit allergy. Methods Pru p 7-related proteins from pollen of Cupressus sempervirens, Juniperus ashei and Cryptomeria japonica were identified using a rabbit anti-Pru p 7 antiserum, purified chromatographically and sequenced by mass spectrometry and bioinformatic comparisons. The C sempervirens protein was produced as a recombinant allergen in Pichia pastoris. IgE antibody binding to pollen GRP proteins was analysed in a peach allergic (n = 54) and a cypress pollen allergic (n = 88) patient population from southern France using ImmunoCAP. Results In each of the three Cupressaceae species studied, a 7 kDa pollen protein related to Pru p 7 was identified and found to comprise an amino acid sequence of 63 residues in length, 92%-98% identical to each other and 67%-68% identical to Pru p 7. The C sempervirens, J ashei and C japonica GRP allergens have been officially recognized by the WHO/IUIS Allergen Nomenclature Sub-Committee and named Cup s 7, Jun a 7 and Cry j 7, respectively. Recombinant Cup s 7 showed IgE antibody binding capacity comparable to that of the purified natural allergen. Among 51 peach allergic subjects sensitized to Pru p 7, substantially higher levels of IgE to Cup s 7 than to Pru p 7 were found. Further, the pollen protein was able to completely outcompete IgE binding to Pru p 7, while the reverse competition effect was modest, consistent with primary sensitization by the pollen allergen. Conclusion and clinical relevance Pru p 7-related pollen allergens from three Cupressaceae species have been characterized and may become useful for the identification of pollinosis patients at risk of developing severe fruit allergy.

International audience; Simulation in healthcare in an way to train professionals but it is not yet use commonly to train patient or their caregivers. Recently, it has been suggested to extend simulations to patients with chronic conditions. Simulations could help patients and caregivers to acquire psychosocial and self-management skills. This approach proved to be effective for the training of healthcare professionals, but its transferability to patients needs to be evaluated. Already, several questions arise. However, by considering simulations as pretexts for debriefing, they enable patients and professionals to assess a concrete situation, implying voluntary and reflexive learning processes. Thus, video recording should be assessed for its role in patient metacognition, defined as knowing about knowing. A taxonomy for simulations dedicated to patients, like that already developed for healthcare professionals, should be considered. Although practical constraints must be identified and addressed, they should not be the primary issue guiding research. The transferability of simulation as an educational technique from professionals to patients and caregivers should be investigated essentially in order to provide a significant benefit to patients.

International audience

International audience; Middle-down mass spectrometry (MD MS) has emerged as a promising alternative to classical bottom-up approaches for protein characterization. Middle-level experiments after enzymatic digestion are routinely used for subunit analysis of monoclonal antibody (mAb)-related compounds, providing information on drug load distribution and average drug-to-antibody ratio (DAR). However, peptide mapping is still the gold standard for primary amino acid sequence assessment, post-translational modifications (PTM), and drug conjugation identification and localization. However, peptide mapping strategies can be challenging when dealing with more complex and heterogeneous mAb formats, like antibody-drug conjugates (ADCs). We report here, for the first time, MD MS analysis of a third-generation site-specific DAR4 ADC using different fragmentation techniques, including higher-energy collisional- (HCD), electron-transfer (ETD) dissociation and 213 nm ultraviolet photodissociation (UVPD). UVPD used as a standalone technique for ADC subunit analysis afforded, within the same liquid chromatography-MS/MS run, enhanced performance in terms of primary sequence coverage compared to HCD- or ETD-based MD approaches, and generated substantially more MS/MS fragments containing either drug conjugation or glycosylation site information, leading to confident drug/glycosylation site identification. In addition, our results highlight the complementarity of ETD and UVPD for both primary sequence validation and drug conjugation/glycosylation site assessment. Altogether, our results highlight the potential of UVPD for ADC MD MS analysis for drug conjugation/glycosylation site assessment, and indicate that MD MS strategies can improve structural characterization of empowered next-generation mAb-based formats, especially for PTMs and drug conjugation sites validation.

International audience; The objective of the SOLSA project (EU-H2020) is to develop an analytical expert system for on-line-on-mine-real-time mineralogical and geochemical analyses on sonic drill cores. As one aspect of the system, this paper presents the building of the hyperspectral library and its incorporation into sparse unmixing techniques for mineral identification. Twenty seven spectra representing 14 minerals have been collected for the library. Three sparse unmixing techniques have been investigated and evaluated using simulated data generated from our hyperspectral library, and real hyperspectral data acquired from a serpentinized harzburgite sample. Among the three techniques, the collaborative sparse unmixing by variable splitting and augmented Lagrangian (CLSUnSAL) method provided the best accurate results on the simulated data. In addition, the results of the CLSUnSAL method show high correlation with that of the QEMSCAN® analysis on the harzburgite hyperspectral data.

International audience; Interdit dans les constructions depuis 1997, l'amiante reste présent dans de nombreux bâtiments à ce jour. Ainsi, lors de travaux ou dans le cas de dégradations des matériaux de construction, des fibres d'amiante sont susceptibles d'être libérées dans l'air. Celles-ci resteront d'autant plus longtemps en suspension qu'elles sont petites, ce qui augmente le risque de les inhaler.A l'heure actuelle, la détermination de la présence d'amiante dans l'air suit un protocole normé (AFNOR NF X 43-050 de janvier 1996) assez lourd, puisque l'analyse est réalisée au laboratoire par Microscopie Electronique en Transmission après fùtration de l'air sur site.Un tel protocole s'accompagne donc de nombreux facteurs d'erreurs. L'objectif du projet PLASMIANTE est de mettre en place une méthode d'analyse directe sur site, permettant de détecter et d'identifier en temps réel les fibres d'amiante potentiellement présentes dans l'air. Pour cela, les fibres seront mises en suspension au sein d'un plasma froid basse pression et analysées à l'aide de différentes méthodes métrologiquestelles que la diffusion multi-angle de la lumière laser, la caractérisation électrique du plasma, la spectroscopie Infra-Rouge et la spectroscopie sur plasma induit par laser (LIBS). Cette étude présente l'objectif du projet, ainsi que les premiers résultats et les challengesauxquels nous serons confrontés lors du projet.

International audience; The SOLSA project (www.solsa-mining.eu) aims to develop an on-line-on-mine expert system coupling sonic drilling, chemical and mineralogical analyses and data treatment. In a first place, this expert system is planned for lateritic profiles of New Caledonia, known to held nickel. The latter is found in two forms in these profiles. First, nickel can be adsorbed on the surface or inserted in the structure of goethite (α-FeOOH) present in the limonites and saprolites. Second, Ni may substitute Mg in different silicates of saprolite, like in garnierite, known to be nickel-rich and corresponding to a mixture of phyllosilicates usually occurring as vein or porosity filling. The SOLSA system will combine several analytical techniques, such as XRD, XRF, Raman spectroscopy, RGB or hyperspectral, and the data collected will be compared to an internal library in order to identify the several minerals present in the lateritic profiles. Therefore, the elaboration of a comprehensive library, taking into account the influence of chemistry on the different signals, is mandatory. Thus, our study focuses on the evolution of the hyperspectral signal (400-2500 nm) with the quantity of nickel for several Ni-bearing silicates present in the lateritic profile. Among the results, nickel influences the behaviour of the doublet in the 1380-1405 nm region for the specific mineral association constituting the garnierite. References: Faust, G.T (1966) American Mineralogist 5: 279. Cluzel, D., Vigier, B. (2008) Resource Geology 58: 161. The SOLSA consortium thanks the European Commission for having sponsored this project (SC5-11d-689868) in the H2020 program.

International audience; We investigated the dissolution of a natural Fe-containing dolomite [Ca 1.003 Mg 0.972 Fe 0.024 Mn 0.002 (CO 3) 2 ] under acidic conditions (pH 3-5.5) with atomic force microscopy (AFM) at 20 °C, and with batch dissolution experiments at 80 °C. Dolomite dissolution proceeded by two identified mechanisms: removal of dolomite layers through spreading and coalescence of etch pits nucleated at defect points, and stepped retreat from surface edges. The dolomite dissolution rate increased when pH decreased (from 0.410 nm s-1 at pH 3 to 0.035 nm s-1 at pH 5). Rates calculated from edge retreat (v edges) and from etch-pit spreading rates (v sum) were consistent; the etch-pit digging rate was almost 10 times slower than its spreading rate. Nanocrystalline secondary phases precipitated in the course of dolomite dissolution at pH 3 and 80 °C were identified as (nano)hematite, ferrihydrite and an ankerite like mineral using X-ray diffraction, transmission electron microscopy, Raman and X-ray photoelectron spectrometry. In addition, Mg enrichment of the surface layer was observed at 80 °C, due to preferential release of Ca in solution. The characterizations performed at a nanocrystalline scale highlighted the role played by impurities in the dolomite dissolution/precipitation scheme and proved that two mechanisms explain the incongruent dolomite dissolution: secondary phase precipitation and preferential release of Ca over Mg.

IF 3.113; International audience; Background: Among septic patients admitted to the intensive care unit (ICU), early recognition of those with the highest risk of death is of paramount importance. We evaluated the prognostic value of Procalcitonin (PCT), mid regional-proadrenomedullin (MR-proADM), copeptine and CT-proendothelin 1 (CT-ProET 1) concentrations. Methods: This was a prospective cohort study, which included 173 septic patient admitted to one ICU. Blood samples for biomarker measure-ments were obtained upon admission and on day 5. The predictive value of each biomarker regarding the risk of death at day 28 was assessed. The fluid balance was evaluated from admission to day 5. Results: All cause ICU mortality was 36.4%. All the biomarkers except CT-ProET-1 were significantly more elevated in the non-survivors than in the survivors upon day 1. Thiswas especially true for MR-proADM(8.6 [5.9] vs. 4.4 [3.9] nmol/L; P

International audience; In order to evaluate the instrumental parameters for the combined on-line-on-mine-real-time expert system SOLSA (http://www.solsa-mining.eu), portable and laboratory analyses were carried out on coarse granite, sandstone, serpentinized harzburgite and siliceous breccia. Each sample was studied at 5 different surface roughnesses (sonic or diamond drilled, cut, polished at 6 µm and 0.25 µm, sample powders). X-ray diffraction (XRD), portable Infra-Red (pIR) and X-ray-fluorescence (pXRF), and laboratory micro-Raman spectroscopy gave complementary and corroborating results. No major effect on the analyses was noted for the selected surface states. pXRF gave variable results except for the homogeneously serpentinized harzburgite, related to coarse or contrasting grain sizes or pores, small spot size (3 mm) and needs close-to-surface analyses. Portable IR (spot size 1.76 cm 2) is carried out close to surfaces while Raman spectroscopy (1-2 µm) is performed at distance. Sampling strategies have to be defined for each lithology. Major challenges for a combined on-line analysis are to adapt the specificities of the techniques to (1) analyse similar surface areas (from ~2 cm 2 (pIR) to < µm (Raman)), (2) smartly combine all the techniques into a single instrument, and (3) develop appropriate databases to reach a reliable " real-time " outcome results, which can be used for more precise geomodeling, and to rapidly define exploration and beneficiation parameters.

International audience; BACKGROUND:Understanding patterns of IgE sensitization in Dermatophagoides-allergic patients living in various geographical areas is necessary to design a product suitable for worldwide allergen immunotherapy (AIT).METHODS:Using a HIFI Allergy customized microarray assay, IgEs specific for 12 purified allergens from Dermatophagoides pteronyssinus or D. farinae were assessed in sera from 1302 house dust mite (HDM)-allergic patients living in various areas. Comprehensive mass spectrometric (MS) analyses were conducted to characterize HDM extracts, as well as purified bodies and feces.RESULTS:Patterns of IgE reactivity to HDM allergens are comparable in all cohorts of patients analyzed, encompassing adults and 5- to 17-year-old children, as well as American, Canadian, European, and Japanese patients. Overall, >70% and >80% of HDM-allergic patients are sensitized to group 1 and group 2 allergens, respectively, from D. pteronyssinus and/or D. farinae species. Furthermore, 20-47% of patients also have IgEs to allergens from groups 4, 5, 7, 13, 15, 21, and 23. All patients have IgEs to allergens present in mite bodies and feces. MS-based analyses confirmed the presence of mite allergens recorded by IUIS in D. pteronyssinus and D. farinae extracts, with groups 2, 8, 10, 11, 14, and 20 prominent in bodies and groups 1, 6, 18, and 23 well represented in feces.CONCLUSIONS:Mite-specific AIT should rely upon a mixture of D. pteronyssinus and D. farinae extracts, manufactured from both feces and bodies. Such a combination is appropriate to treat children and adult Dermatophagoides-allergic patients from Asia, Europe, and North America.

International audience; In-line monitoring tools are still required to understand and control animal cell processes, particularly in the case of vaccine production. Here, in situ near-infrared spectroscopy (NIRS) quantification of components in culture media was performed using microcarrier-based cultivations of adherent Vero cells. Because microcarriers were found to interfere with NIRS spectra acquisition, a suitable and innovative in situ calibration was developed for bioreactor cultures. A reliable and accurate NIRS technique for the quantification of glucose and lactate was established, with a calibration standard error of 0.30 and 0.21 g l−1, respectively. The robustness of this method was evaluated by performing NIRS calibration with operating conditions similar to those of industrial processes, including parameters such as microcarrier concentrations, cell seeding states and changes in analyte concentration due to feed and harvest strategies. Based on this calibration procedure, the predicted analyte concentrations in unknown samples was measured by NIRS analyses with an accuracy of 0.36 g l−1 for glucose and 0.29 g l−1 for lactate.

BackgroundInsertions/deletions (InDels) and more specifically presence/absence variations (PAVs) are pervasive in several species and have strong functional and phenotypic effect by removing or drastically modifying genes. Genotyping of such variants on large panels remains poorly addressed, while necessary for approaches such as association mapping or genomic selection.ResultsWe have developed, as a proof of concept, a new high-throughput and affordable approach to genotype InDels. We first identified 141,000 InDels by aligning reads from the B73 line against the genome of three temperate maize inbred lines (F2, PH207, and C103) and reciprocally. Next, we designed an Affymetrix® Axiom® array to target these InDels, with a combination of probes selected at breakpoint sites (13%) or within the InDel sequence, either at polymorphic (25%) or non-polymorphic sites (63%) sites. The final array design is composed of 662,772 probes and targets 105,927 InDels, including PAVs ranging from 35bp to 129kbp. After Affymetrix® quality control, we successfully genotyped 86,648 polymorphic InDels (82% of all InDels interrogated by the array) on 445 maize DNA samples with 422,369 probes. Genotyping InDels using this approach produced a highly reliable dataset, with low genotyping error (~3%), high call rate (~98%), and high reproducibility (>95%). This reliability can be further increased by combining genotyping of several probes calling the same InDels (99.9% of call rate for 5 probes). This “proof of concept” tool was used to estimate the kinship matrix between 362 maize lines with 57,824 polymorphic InDels. This InDels kinship matrix was highly correlated with kinship estimated using SNPs from Illumina 50K SNP arrays.ConclusionsWe efficiently genotyped thousands of small to large InDels on a sizeable number of individuals using a new Affymetrix®Axiom®array. This powerful approach opens the way to studying the contribution of InDels to trait variation and heterosis in maize. The approach is easily extendable to other species and should contribute to decipher the biological impact of InDels at a larger scale.

International audience; Two methods are described and compared to measure electric fields (EFs) in the plume of an atmospheric pressure plasma jet. The first one uses an electric-optical probe made of a BSO crystal. In this case, the measurement is based on Pockels effect. The second one is Stark spectroscopy of the Helium line at 492nm. From the results obtained, it appears that the presence of a dielectric target triggers an enhancement of the electric field in the plume near the target. Moreover, it will be shown that both techniques have their advantages and are complementary.

The atmospheric pressure multi-plasma jet produces an array of individual plasma jets which originate from the branching of a single ionization wave (IW). The use of arrays of such plasma jets could enable treatment of larger surface areas than is possible with a single plasma jet. In this paper, we discuss results from a combined experimental and two-dimensional modeling investigation of the behavior of IWs in an atmospheric pressure plasma multi-jet device. In this multi-jet, a rare gas is flowed through a tube having a line of holes, producing gas jets into the ambient from each of the holes. A primary ionization wave (PIW) propagates through the tube which launches a series of secondary ionization waves (SIWs) propagating out each hole through the plumes of the individual gas jets. The propagation of the SIWs is more intense using a positive polarity voltage pulse due to the higher electric field at the ionization front. The diameter of the holes determines the delay of the SIW after passage of the PIW past the hole, with smaller holes resulting in larger delays. The larger delay results from a smaller view angle for photoionization outside the tube from photons originating in the PIW. Higher helium flow rates result in a greater tendency for SIW propagation because the air concentrations in the individual gas jets outside the tube are lower and so the electron temperature is higher. The interaction between SIWs is primarily electrostatic, and is a sensitive function of geometric parameters including proximity of ground planes and the spacing between the holes through which these SIWs emerge.

International audience; Atmospheric pressure plasma jets have been extensively studied in the last decade. Thanks tothe production of high transient electric field and reactive nitrogen and oxygen species, manyapplications have been found from material processing to biomedical field. One of the remainingchallenge is the size of the jet. At atmospheric pressure, the plasma plume diameter on a target isof the order of a millimeter leading to difficulties where larger areas must be treated. In order totreat extended wounds, to sterilize wider surfaces or to address large-scale processingapplications, one needs to develop plasma jet arrays.The reactor used in this work is a Plasma Gun made of a high voltage electrode inside a glasscapillary, surrounded by a grounded electrode. A power supply feeds it with 14kV microsecondpulses from single shot to 4 kHz. The pulsed atmospheric pressure plasma stream (PAPS) [1],composed of an ionization wave front followed by a plasma column, originating from thisdielectric barrier discharge, propagates in helium inside the capillary. A linear multijets assemblyis added at the end of the capillary. Plasma multijets production have been studied varyingfollowing parameters: material of the assembly, size of holes, their distance, wall thickness...This work focuses on the differences between a dielectric and a metallic assembly. ICCDcamera recordings show how the ionization wave propagates inside a transparent dielectricassembly, igniting the jets one after another.[2] However, as the PAPS reaches a metallic one, ittransfers its electric potential to the assembly. Then, no plasma propagates into due to theabsence of electric field but new plasma ionization waves are generated at each hole at the sametime. These two different ways of ignition trigger differences in intensity and homogeneitybetween the jets. The presence of species was also investigated via EOS or optical filters. ASchlieren setup has been also used to visualize gas flows with and without plasma with differentgas flow rates, sizes and numbers of holes. With large enough holes the drop of pressure in thedifferent holes becomes visible as jets are shorter and shorter. Additionally to the ionic wind ineach jet, as already studied in [3], interactions between them add a new feature. Repulsive forcesbend the jets, more strongly for the first and last ones and in negative polarity. Electric fieldsmeasurements run with an electro-optic probe, made by Kapteos and based on Pockels effects,with both assemblies will be compared.X.D. acknowledges his grant funding Thermofisher Scientific INEL/Région Centre Val de Loire.References[1] E. Robert, V. Sarron, D. Riès, S. Dozias, M. Vandamme and J M. Pouvesle, Plasma SourcesScience and Technology, 21, 0349017 (2012)[2] AM. Lietz, X. Damany, JM. Pouvesle, E. Robert, MJ. Kushner, Bulletin of the AmericanPhysical Society, 62, Student Excellence Award Finalist: Atmospheric Pressure Plasma Multijets:Fundamental Properties[3] T. Darny, JM. Pouvesle, J. Fontane, L. Joly, S. Dozias, and E. Robert, Plasma SourcesScience and Technology, 26, 105001 (2017).

International audience; Atmospheric pressure plasma jets have been extensively studied for several years as theyshowed very promising results in numerous fields such as material processing or plasma medicine.What makes cold plasma interesting is the presence of electrons, ions, reactive oxygen andnitrogen species, visible and UV light and high transient electric fields (EF). Even if the latter playa key role, from the production and propagation of the plasma to the efficiency of applications,they are far from being fully understood. This work focuses on the comparison of measurementsof EF produced by a Plasma Gun (PG) discharge with an electro-optic probe based on Pockelseffect [1] with 2D simulations of atmospheric pressure discharges propagating in a geometry closeto the Plasma Gun’s one. Plasma Gun consists in a vertically downward oriented capillary with aninner high-voltage electrode and an outer grounded one. Plasma is powered with μs-durationvoltage pulses from single shot to 4kHz.In [2] the electric field is evaluated by the simulations inside the capillary, in the glass andoutside. The aim of this work is to compare the radial profile of the electric field outside thecapillary between experiments and simulations to get information on the plasma inside it. Theelectro-optic probe was placed at different levels alongside the capillary and was getting far fromit. Measurements were executed every 5mm over 5cm. At the middle of the capillary a decreaseinversely proportional to the distance has been found. It reminds the shape of an EF produced byan infinite uniformly charged cylinder. 2D simulations were in a good agreement finding also thesame slope for EF. But simulations permit also to get information on the distribution of chargedensity and especially to know if the main contribution is from volume or surface charge density.Results show that the radial profile of EF outside the tube is mostly determined by the volumecharge density in positive polarity while in negative polarity the surface charge density isdominant. Simulations have provided values of average volume charge density in the order of 7.5nC/cm3 in positive polarity and of average surface charge density around 1nC/cm² in negativepolarity. Near the electrodes, a decrease inversely proportional to the square of the distance hasbeen found, showing that there is an axial position dependence. A time dependence investigationwill also be presented.X.D. acknowledges his grant funding Thermofisher Scientific INEL/Région Centre Val de Loire.References[1] G. Gaborit et al., IEEE Trans. Plasma Sci., 42 (2014).[2] P. Viegas, F. Pechereau and A. Bourdon, Plasma Source Science and Technology, in press(2018)

International audience; In this work we present Schlieren images of a Plasma Gun discharge fed not only with helium but also for the first time with neon and argon buffers. It is demonstrated that efficient gas flow channelling is observed with operation of the PG with any of the three gases. Such gas flow channelling is also proven to be dependent on voltage polarity and frequency. Analysis of the role of molecular admixtures (N2 or O2) confirms the non-thermal nature of the effect and the potential crucial role of large negative ions.

National audience; Large extent of Copy Number Variants (CNV), i.e changes in the copy number of genes between individuals, have been recently highlighted in maize using Comparative Genomic Hybridization array or massive parallel sequencing. However, their contribution to genetic diversity and to traits variation remains mostly unknown since these technologies are very expensive and labor demanding. To address these issues, we developed an original approach based on Affymetrix Axiom technology, to genotype an extreme form of CNV called Present Absent Variant (PAV) in maize. PAV was defined as DNA sequence >1kbp that is present in some individuals but absent from others. Using our high throughtput genotyping array, we genotyped 60 026 PAV on 356 inbred lines from an association panel representing worldwide maize genetic diversity. This panel has been previously genotyped using 50k SNP Illumina Infinium array and phenotyped for 29 agronomic traits related to yield, phenology and plant architecture. We analyzed and compared how PAV and SNP polymorphisms were globally structured in these panel by analyzing relatedness and genetic structuration. We observed that genetic structuration and relatedness obtained using PAV were globally similar to those obtained with SNP. We analyzed extent of linkage disequilibrium (LD) between SNP and PAV. We observed that LD were less extended between PAV and SNP than between SNP suggesting that the effect of these polymorphisms on traits could be not easily captured by linkage disequilibrium with SNP from 50K array. We performed a genome wide association study on 29 agronomic traits and identified several PAV significantly associated with different agronomic traits.

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International audience; Most visitors of a sauna appreciate the heat pulse that is perceived when water is poured on the stones of a sauna stove. However, probably only few bathers are aware that this pleasant heat pulse is caused by latent heat being released onto our skin due to condensation of water vapour. In order to quantify the proportion of condensation water versus sweat to dripping water of test persons we conducted sauna experiments using isotopically labelled (δ18O and δ2H) thrown water as tracer. This allows differentiating between ‘pure sweat’ and ‘condensation water’. Two ways of isotope mass balance calculations were applied and yielded similar results for both water isotopes. Accordingly, condensation contributed considerably to dripping water with mean proportions of 52 ± 12 and 54 ± 7 % in a sauna experiment in winter semester 2011/12 and 30 ± 13 and 33 ± 6 % in a sauna experiment in winter semester 2012/13, respectively, depending on the way of calculating the isotope mass balance. It can be concluded from the results of our dual isotope labelling sauna experiment that it is not all about sweat in the sauna.

International audience; Whilst largely considered an inert material, biochar has been documented to contain a small yet significant fraction of microbially available labile organic carbon (C). Biochar addition to soil has also been reported to alter soil microbial community structure, and to both stimulate and retard the decomposition of native soil organic matter (SOM). We conducted a short-term incubation experiment using two C-13-labelled biochars produced from wheat or eucalypt shoots, which were incorporated in an aridic arenosol to examine the fate of the labile fraction of biochar-C through the microbial community. This was achieved using compound specific isotopic analysis (CSIA) of phospholipid fatty acids (PLFAs). A proportion of the biologically-available fraction of both biochars was rapidly (within three days) utilised by gram positive bacteria. There was a sharp peak in CO2 evolution shortly after biochar addition, resulting from rapid turnover of labile C components in biochars and through positive priming of native SOM. Our results demonstrate that this CO2 evolution was at least partially microbially mediated, and that biochar application to soil can cause significant and rapid changes in the soil microbial community; likely due to addition of labile C and increases in soil pH. (C) 2013 Elsevier B.V. All rights reserved.

International audience; This article reports on the impact of shear on crystallization upon cooling of palm oil. Samples were cooled down under shear from 70 to 10 degrees C, then kept at this temperature, while performing rheological measurements using a controlled shear rate rheometer and rheo-optical observations using optical microscopy and small-angle light scattering. Shear rates between 1 and 300 s(-1) were investigated. Two crystallization steps were observed, characterized by associated viscosity increases. The effect of shear on these 2 crystallization processes was investigated. Shear was shown to influence almost all of the steps of the structuring process of the crystallizing palm oil. The spherulite size and growth rate during the 1st crystallization are affected by shear. The onset time of the 2nd crystallization process strongly depends on the extent of shear. The steady state structures after the 1st and 2nd crystallization processes constituted of a suspension of aggregates of spherulites are controlled by the applied shear rate. Practical Application: The texture of crystallized vegetal fats and subsequent end product properties depend on the structure developed during the crystallization process. This structuring process is strongly influenced by the thermo-mechanical history applied to the product (cooling rate, degree of undercooling, annealing time, application of flow). This article shows how the shear rate as well as extent of shear affects the different steps of the crystallization and aggregation processes in the case of palm oil after the 1st crystallization.

International audience; To explore the variability in biosensor studies, 150 participants from 20 countries were given the same protein samples and asked to determine kinetic rate constants for the interaction. We chose a protein system that was amenable to analysis using different biosensor platforms as well as by users of different expertise levels. The two proteins (a 50-kDa Fab and a 60-kDa glutathione S-transferase [GST] antigen) form a relatively high-affinity complex, so participants needed to optimize several experimental parameters, including ligand immobilization and regeneration conditions as well as analyte concentrations and injection/dissociation times. Although most participants collected binding responses that could be fit to yield kinetic parameters, the quality of a few data sets could have been improved by optimizing the assay design. Once these outliers were removed, the average reported affinity across the remaining panel of participants was 620 pM with a standard deviation of 980 pM. These results demonstrate that when this biosensor assay was designed and executed appropriately, the reported rate constants were consistent, and independent of which protein was immobilized and which biosensor was used. (C) 2008 Elsevier Inc. All rights reserved.

National audience

In September 2023, the two largest bioimaging networks in the Americas, Latin America Bioimaging (LABI) and BioImaging North America (BINA), came together during a 1-week meeting in Mexico. This meeting provided opportunities for participants to interact closely with decision-makers from imaging core facilities across the Americas. The meeting was held in a hybrid format and attended in-person by imaging scientists from across the Americas, including Canada, the United States, Mexico, Colombia, Peru, Argentina, Chile, Brazil and Uruguay. The aims of the meeting were to discuss progress achieved over the past year, to foster networking and collaborative efforts among members of both communities, to bring together key members of the international imaging community to promote the exchange of experience and expertise, to engage with industry partners, and to establish future directions within each individual network, as well as common goals. This meeting report summarises the discussions exchanged, the achievements shared, and the goals set during the LABIxBINA2023: Bioimaging across the Americas meeting., (© 2024 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.)