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Pyrolysis-GC/MS is increasingly used to quantify microplastics (MP) in environmental samples. In general, prior to analysis, purification steps are carried out to reduce the environmental matrix in sediment samples. The conventionally used protocol of density separation followed by digestion of organic matter does not allow for complete isolation of MP from the associated organic and mineral matter. Among the pyrolysis products used as indicator compounds for plastic polymers, some may originate from other substances present in the environmental samples. In this paper, the indicator compounds are reviewed for the most common polymers: PE, PP, PS, PET and PVC and selected taking into account potential interactions with substances present in environmental matrices. Even after a purification step, a residual mineral fraction remains in a sediment sample, including matrix effects. This effect may be positive or negative, depending on the investigated polymer and is thus important to consider when using Pyr-GC/MS for the quantification of MP in sediment samples. It also shows that no external calibration can be used to reliably quantify MP in such samples and that the use of internal standards is compulsory.

The particle number concentration (PNC) of dilute nanoparticle dispersions can be determined by single particle inductively coupled plasma-mass spectrometry (sp-ICP-MS). Virtually equal to zero for very dilute dispersions, the difference between the number of nanoparticles having entered the plasma of the instrument and the number of detectable spikes in the time scan increases in a strongly nonlinear fashion with the PNC. This counting bias, which was unquantified yet, is due to particle event coincidences in the time scan and precludes at first sight the possibility to get meaningful information about the PNC of even moderately concentrated dispersions. In this article, we show that the counting bias is related to a stochastic process that models the spike occurrences in the time scan. This stochastic theory turns out to be amenable to analytical methods and yields universal predictions. We confirm their validity through Monte Carlo simulations and experiments with gold nanoparticle dispersions, for the full spectrum of PNC values we tested.

The African citrus triozid, Trioza erytreae Del Guercio (Hemiptera: Triozidae) is one of the primary vectors of the bacterium Candidatus Liberibacter spp. which causes citrus greening, a disease of global economic importance in citrus production. Despite its economic importance, little is known about its chemical ecology. Here, we used behavioral assays and chemical analysis to study the chemical basis of interaction between T. erytreae and one of its preferred host plants, Citrus jambhiri. In dual choice Y-tube olfactometer assays, lemon leaf odors attracted females but not males compared to plain air or solvent controls. However, in a petri dish arena assay, both sexes were arrested by lemon leaf odors. Coupled gas chromatography-mass spectrometry (GC/MS) analysis revealed quantitative differences in the odors of flushing and mature leaves, dominated by terpenes. Twenty-six terpenes were identified and quantified. In Petri dish arena assays, synthetic blends of the most abundant terpenes mimicking lemon flushing leaf odors elicited varying behavioral responses from both sexes of T. erytreae. A nine-component blend and a blend of the three most abundant terpenes; limonene, sabinene and β-ocimene arrested both sexes of T. erytreae. In contrast, a six-component blend lacking in these three components elicited an avoidance response in both sexes. Furthermore, both sexes of T. erytreae preferred the three-component synthetic blend to lemon crude volatile extract. These results suggest that lemon terpenes might be used in the management of T. erytreae.

Spectrally efficient waveforms have been extensively investigated in the last few years for the upcoming 5G systems. Filter Bank Multicarrier (FBMC) and Generalized Frequency Division Multiplexing (GFDM) are two of the best contenders that offer very low out of band emissions. To make better use of the available spectral resources, we propose coupling the 5G waveforms candidates with Cognitive Radio (CR). To perform spectrum sensing, we rely on cyclostationary detection. Although some papers have addressed second order cyclic features of the aforementioned waveforms, they are special cases of the results presented herein. In fact, in the present work, we first derive the explicit theoretical mth order pth conjugate cyclic cumulants of both FBMC and GFDM. Our analysis reveals that FBMC has distinctive cyclostationary properties. GFDM exhibits rich cyclic features as a result of the block filtering, the Cyclic Prefix (CP) insertion and the use of subsymbol guards. The obtained results are then exploited for signal detection purposes. Detection probability of FBMC is the best among the considered waveforms, followed by GFDM, where both outperform OFDM detection, specially if the used CP is low.

International audience; The resort to high pressure - above 50 MPa typically - being on the rise orotherwise often constituting a disruptive technology in a growing number of fields, e.g.pharmaceutical, nutritional or automotive, this article intends to provide any project aimedat carrying out measurements under high pressure with relevant information andrecommendations for assessing the implications of its implementation. The first partdescribes the European regulatory and prescriptive framework, the main and specificcharacteristics, as well as the limitations of the various suitable high-pressureequipments. The second part describes the measurement techniques that can beimplemented therein.; Le recours relativement récent aux hautes pressions - au-delà de 50 MPatypiquement - progressant ou constituant une potentielle technologie de rupture dans deplus en plus nombreux domaines, comme la pharmaceutique, l'agroalimentaire oul'automobile, le présent article entend apporter les éléments d’information suffisants, touten fournissant les recommandations nécessaires, pour cerner les tenants et aboutissantsqu’implique tout projet de mesures sous haute pression ; la première partie décrit leséquipements où de telles mesures peuvent être effectuées, leur cadre réglementaire etnormatif, leurs caractéristiques principales, leurs spécificités et leurs limites ; la deuxièmepartie décrit les techniques de mesure qui peuvent y être mises en oeuvre.

International audience; This dataset presents 127 raw near infrared spectra of different organic samples acquired on three different spectrometers in three different labs. An example of data processing is shown to create six spectra transfer models between the three spectrometers (two by two). In order to build and validate these transfer models, the dataset was split into two sets of spectra: a first set was used to compute six spectra transfer models thanks to the Piecewise Direct Standardisation function (PDS). A second set of spectra, independent of the first one was used to validate transfer models. Spectrum treatments and models were created on ChemFlow (https://vm-chemflow-francegrille.eu/), a free online chemometric software that includes all the necessary functions.

Une connaissance précise des désintégrations par interaction faible, transitions bêta et captures électroniques, est indispensable dans de nombreux domaines scientifiques, des plus fondamentaux aux plus applicatifs : tests du Modèle Standard, détection de la matière noire et du neutrino stérile, métrologie des rayonnements ionisants, caractérisation des détecteurs, médecine nucléaire, puissance résiduelle et surveillance en temps réel des réacteurs nucléaires, ou encore gestion du combustible après irradiation. La question de la qualité, de la précision et de la complétude des données nucléaires est devenue un enjeu important dans ces différents domaines. Ces dix dernières années, le Laboratoire National Henri Becquerel s’est impliqué dans cette thématique, fort de son expertise en métrologie de la radioactivité et en évaluation de données atomiques et nucléaires. Les experts en cryogénie du laboratoire ont développé une nouvelle technique de mesure par calorimétrie et l’ont appliquée avec succès à la spectrométrie bêta. Un système de détection dédié, utilisant des détecteurs silicium, a été élaboré conjointement à une technique de préparation spécifique de source radioactive et à un processus de déconvolution spectrale. En parallèle, une étude théorique a été menée pour améliorer les prédictions, menant notamment à la création du code de calcul BetaShape. Cette étude a permis d’améliorer et de compléter les données nucléaires évaluées. Les résultats obtenus placent le Laboratoire National Henri Becquerel au meilleur niveau mondial sur cette thématique. L’expertise acquise permet d’envisager une contribution significative à des sujets de physique fondamentale qui seront très structurants dans les années à venir.

This study aimed at investigating the chemical composition and microstructure of spray dried camel and cow milk powders' surfaces with two different milk-fat contents (1 and 20g 100 g−1). The SEM (Scanning Electron Microscopy) micrographs showed that spherical particles with a ‘brain’-type surface for both milk powders were produced. The surface roughness (Ra) of whole (WDMP) and skimmed (SDMP) camel milk powders (Ra = 7.6 ± 0.4 nm and 5.6 ± 0.7 nm, respectively) were significantly lower as compared with the partially skimmed (PSCMP) and skimmed (SCMP) cow milk powders. The XPS (X-ray Photoelectron Spectroscopy) analysis highlighted that the surface of skimmed camel milk powders contained twice the lactose amount (17.7 ± 0.8%) as compared to cow milk powders (8.7 ± 0.4%). Furthermore, both milk powders showed the overexposure of proteins and fats at their surfaces regardless of the fat content. The CLSM (Confocal Laser Scattering Microscopy) micrographs highlighted that most of the camel milk fat globules were encapsulated by the proteins near the powder surface. Camel milk fat behavior during particle formation was attributed to their lower size distribution and their higher crystallization temperature.

When biomass is thermally treated, the enrichment of carbon in the remaining “green coal” is correlated with the temperature and duration. Other properties related to the energetic properties of the torrefied biomass are closely related to chemical modifications and correlated to the material mass loss occurring during the thermal degradation. The possibility of using near infrared spectrometry has been investigated to predict the mass loss of Pinus sylvestris wood torrefied at temperatures ranging from 220°C to 300°C with durations varying from 1 minute to 10 hours. A first mass loss prediction model (NIR‐260) associated with the mean torrefaction temperature of 260°C was developed, and appeared suitable only for this temperature due to specific chemical reactions rate. A second model (NIRS‐All), using all available data was constructed and showed an accurate mass loss prediction, for both low (220°C) and high temperatures (300°C). The main differences between NIRS‐260 and NIRS‐All models are mainly attributed to the thermal modification of hemicelluloses and cellulose fractions occurred during the wood torrefaction. The results showed near infrared spectrometry combined with multivariate calibration modeling have potential utility in an industrial context as a standardized continuous method to figure out the mass loss of biomass during torrefaction by a rapid characterization. Novelty Statement The novelty concerns the use of the Near Infrared Spectrometry (NIRS) combined with multivariate calibration modeling as a standardized method for determining the mass loss biomass during torrefaction by a rapid and nondestructive characterization. A model was constructed and showed an accurate mass loss prediction, for both low (220°C) and high temperatures (300°C). Near infrared spectrometry have potential utility in an industrial context as a standardized continuous method.

Identifying and characterizing the enzymes responsible for an observed activity within a complex eukaryotic catabolic system remains one of the most significant challenges in the study of biomass-degrading systems. The debranching of both complex hemicellulosic and pectinaceous polysaccharides requires the production of α-l-arabinofuranosidases among a wide variety of coexpressed carbohydrate-active enzymes. To selectively detect and identify α-l-arabinofuranosidases produced by fungi grown on complex biomass, potential covalent inhibitors and probes which mimic α-l-arabinofuranosides were sought. The conformational free energy landscapes of free α-l-arabinofuranose and several rationally designed covalent α-l-arabinofuranosidase inhibitors were analyzed. A synthetic route to these inhibitors was subsequently developed based on a key Wittig–Still rearrangement. Through a combination of kinetic measurements, intact mass spectrometry, and structural experiments, the designed inhibitors were shown to efficiently label the catalytic nucleophiles of retaining GH51 and GH54 α-l-arabinofuranosidases. Activity-based probes elaborated from an inhibitor with an aziridine warhead were applied to the identification and characterization of α-l-arabinofuranosidases within the secretome of A. niger grown on arabinan. This method was extended to the detection and identification of α-l-arabinofuranosidases produced by eight biomass-degrading basidiomycete fungi grown on complex biomass. The broad applicability of the cyclophellitol-derived activity-based probes and inhibitors presented here make them a valuable new tool in the characterization of complex eukaryotic carbohydrate-degrading systems and in the high-throughput discovery of α-l-arabinofuranosidases.

International audience; A novel analytical method was developed for quantitative determination of eight limonene-derived monoterpenes responsible for the mint aroma in red wine. As these aromatic compounds are present at trace levels, a new dual extraction approach was proposed, combining solid-phase extraction (SPE) and stir bar sorptive extraction (SBSE), followed by gas chromatography-mass spectrometry analysis. The various parameters affecting the efficiency of extracting the analytes from wine samples in both the SPE and SBSE steps were first investigated, to determine the best compromise for the simultaneous analysis of the compounds studied. Following preliminary optimization of the dilution factor, phase ratio, and methanol content in the SBSE sample, cartridge sorbent mass, type of solvent, elution volume, and wine sample volume in the pre-concentration SPE step were studied. Highest response values were obtained when a 90 mL wine sample was extracted on a 500 mg SPE C18 cartridge and eluted with 1.5 mL methanol. The wine extract was then diluted in 10 mL water to obtain a final methanol content of 15% before the SBSE step. Good linearity, repeatability, reproducibility, accuracy and the required low detection and quantification limits were obtained under the conditions described, making this SPE-SBSE combination a suitable, powerful tool for routine analysis of the selected limonene-derived mint aroma compounds in large series of wine samples. Finally, the validated method was applied to 15 commercial red Bordeaux wines, aged from 3 to 23 years. Most of the compounds studied, present within the ng.L-1 range, were easily quantified for the first time in wine.

The aromatic descriptor "green", reflecting grape unripeness in French red wines, is frequently associated with the levels of 3-alkyl-2-methoxypyrazines, particularly 3-isobutyl-2-methoxypyrazine (IBMP), which has bell pepper nuances. Nevertheless, not all green aromatic expressions in red wines correlate with 3-alkyl-2-methoxypyrazine concentrations. This study considered sensory and chemical approaches using Cabernet Sauvignon wines obtained from grapes harvested at one-month intervals during the 2014 and 2015 vintages to investigate other volatile odoriferous compounds. Semipreparative HPLC fractionation of wine extracts revealed a fraction with specific green aromas in the early harvest wines. Its sensory impact was confirmed by omission and reconstitution tests. Then, multidimensional gas chromatography coupled with olfactometry and mass spectrometry (MDGC-O-MS/TOF) was used for molecular characterization of the aroma compounds associated with the green aromas. Surprisingly, eucalyptol (1,8-cineole), with menthol odor was highlighted and assayed at concentrations sometimes above its olfactory detection threshold in Cabernet Sauvignon and Fer Servadou wines. Sensory tests confirmed its impact at several concentrations detected in French red wines (up to 2.61 ± 0.03 μg/L) on the menthol nuance and overall green perception, particularly via an additive effect with IBMP. Quantitation of 1,8-cineole in Cabernet Sauvignon and Merlot grapes during berry development in 2015 revealed its varietal origin with abundant concentrations in unripe berries and decrease during grape maturation. Moreover, the implication of an invasive plant (Artemisia verlotiorum) growing in certain vineyards was shown to be responsible for increased 1,8-cineole concentrations in some wines.

International audience; In the dataset presented in this article, sixty sugarcane samples were analyzed by eight visible / near infrared spectrometers including seven micro-spectrometers. There is one file per spectrometer with sample name, wavelength, absorbance data [calculated as log10 (1/Reflectance)], and another file for reference data, in order to assess the potential of the micro-spectrometers to predict chemical properties of sugarcane samples and to compare their performance with a LabSpec spectrometer. The Partial Least Square Regression (PLS-R) algorithm was used to build calibration models. This open access dataset could also be used to test new chemometric methods, for training, etc.

L'utilisation de fibres optiques à réseaux de Bragg (FBG) comme thermomètres dans des véhicules spatiaux et autres environnements sous rayonnement requiert une caractérisation des défauts créés par les rayons cosmiques, ainsi que leur évolution sous recuit. Les irradiations des fibres par des protons de 5 MeV ont été faites à des fluences entre 109 cm--2 et 1015 cm--2 afin de reproduire les effets des rayons cosmiques à l'orbite géodésique tel que prévu par la littérature et le programme SPENVIS. L'absorption optique des fibres mesurée par spectrométrie met en lumière la présence de nouveaux défauts optiquement actifs à partir d'une fluence de 109 cm--2. Les défauts principaux qui modifient la transmission dans les fibres sont E, D0, D et POR. À une énergie de 3.5 eV, une bande de photoluminescence est créée à partir d'une fluence de 109 cm--2. Grâce à une filtre passe-haut, il a été possible de déterminer que cette bande provenait d'une photoluminescence excitée d'un défaut produisant une bande d'absorption à des longueurs d'onde supérieures à 420 nm. Les mesures ToF-SIMS ont mis en évidence la présence de chlore dans les fibres, créant une bande d'absorption à 3.8 eV. Ceci confirme la méthode de fabrication de la silice utilisée pour les fibres optiques de cette recherche. La présence de germanium implique aussi la présence d'une bande à 5.14 eV, trop faible pour être observée par nos appareils de mesure. Les recuits sous atmosphère contrôlée effectués à différentes températures de 300°C, 500°C, 700°C et 900°C montrent que l'annihilation des défauts n'est pas caractérisée par un processus activé thermiquement avec une seule barrière d'énergie importante. Elle se produit plutôt graduellement, de manière semblable à la relaxation dans les matériaux amorphes. Les défauts de chlore, D0 et POR sont encore observables à une température de 900 °C., The use of fiber Bragg grating as thermometers in space and radioactive environments requires a characterization of the optical defects created by cosmic rays, as well as their evolution under annealing. The irradiation of the fibers by protons of 5 MeV have been carried out at different fluences between 109 cm--2 and 1015 cm--2 to reproduce the effect of cosmic rays predicted by the SPENVIS program. The fibers absorption measured by spectrometry showed the creation of new optical defects after a fluence of 109 cm--2. The main defects modifying the transmission in the fibers are E, D0, D and POR. At 3.5 eV, a photoluminescence band is created after a fluence of 109 cm--2. With a high-pass filter, it was possible to determine that this band was made by excited photoluminescence by a defect located at wavelenghts higher than 420 nm. Tof-SIMS measurements confirmed the presence of chlorine in fibers, which creates an absorption band at 3.8 eV. This enables us to confirm the silica manufacturing method, which is used to make the optical fibers. The presence of germanium implies that there should be an absorption band ad 5.14 eV, but it is too weak to be observed by our measuring methods. The annealing under nitrogen atmosphere carried out at 300°C, 500°C, 700°C and 900°C shows that the defect annealing is not characterized by a thermally activated process featuring a single activation energy, but occurs gradually over a wide temperature span, similar to what is observed during the relaxation of amorphous materials. Chlorine, POR and D0 defects have been observed at 900 °C.

Neutrons are studied in various domains as, for example, particles of interest in fundamental physics, tool in biology and elemental analysis, or danger for human in radioprotection. The measurement of the neutron energy is necessary in all these domains, but the characteristics of the spectrometers can vary greatly from an application to another. In the field of this thesis, we conceived a recoil proton telescope using ultra-fast CMOS pixels sensors. This compact detector allows a real-time reconstruction of the neutron spectrum up to very high flux. The applications developed during this thesis are precision measurement at the AMANDE accelerator between 4 and 20 MeV, as part of a collaboration with IRSN-Cadarache, and the characterization of secondary neutrons produced in protontherapy treatment rooms., Les neutrons sont étudiés dans des domaines divers en tant, par exemple, que particules d’intérêt pour la physique fondamentale, outil pour la biologie ou l'analyse élémentaire, ou encore danger pour l'Homme en radioprotection. La mesure de l'énergie des neutrons est indispensable pour l'ensemble de ces domaines, mais les caractéristiques des spectromètres peuvent varier grandement d'une application à l'autre. Dans le cadre de cette thèse, nous avons développé un télescope à protons de recul doté de capteurs à pixels CMOS ultra-rapides. Ce détecteur compact permet une reconstruction en temps-réel du spectre neutron jusqu'à de très hauts flux. Les applications développées au cours de ce thèse sont la mesure de précision auprès de l'accélérateur AMANDE entre 4 et 20 MeV, dans le cadre d’une collaboration avec l’IRSN-Cadarache, et la caractérisation des neutrons secondaires produits en salle de traitement de protonthérapie.

Le développement de toute nouvelle technologie sans fil passe par une phase de simulation système, afin d'identifier les paramètres qui impactent la qualité de transmission et de définir les limites du réseau. Ces simulateurs doivent alors reposer sur des modèles de canaux précis et réalistes permettant de mieux prédire les indicateurs de performance du système. La future génération des réseaux mobiles 5G, en cours de standardisation pour un déploiement en 2020, n'en est pas une exception. En effet, de nombreux travaux de recherche effectués dans ce contexte se sont consacrés à la mise en oeuvre de nouveaux modèles adaptés aux différents scénarios de propagation envisagés pour cette technologie (micro-urbain, macro-urbain, bâtiments, V2V, D2D, ...). Afin d'assurer une communication optimale en termes de ressources énergétiques et spectrales, la nouvelle génération des terminaux 5G doit être également en mesure de connaître en permanence son environnement. Cela repose sur l'implémentation d'un système de localisation, notamment dans les milieux contraints où les systèmes de positionnement satellitaires ne sont pas disponibles. Dans le domaine des transports, un exemple assez récurent de ces scénarios est celui des tunnels. Bien qu'ils soient des milieux « indoor », ce type d'environnements est caractérisé par le phénomène de guidage d'onde dû à sa structure géométrique et des propriétés des matériaux de ses murs. Ainsi, une extension des modèles de propagation développés pour les systèmes 5G s'avère alors nécessaire, afin de prendre en considération ce cas d'usage. Le modèle proposé dans le cadre de cette thèse adopte une approche hybride pour reproduire l'effet du canal dans une chaîne de localisation. Dans un premier temps, les paramètres de propagation sont calculés par un simulateur à tracé de rayons. Ce dernier décrit avec une grande précision le comportement des ondes radio à l'intérieur du tunnel. Néanmoins, son coût en termes de temps de calcul est énorme. Les données déterministes obtenues sont alors analysées afin d'identifier les lois statistiques qui les régissent. Cette étape nous permet ainsi de créer une base de données contenant pour chaque paramètre la distribution qui lui correspond. Cette dernière est ensuite utilisée pour générer d'une manière stochastique les coefficients du canal utiles à notre système de localisation, à sa- voir l'amplitude et le retard relatifs à chaque trajet. La réponse impulsionnelle du canal, ainsi construite, servira à estimer la distance entre les deux antennes de transmission. En fonction des conditions de propagation ainsi que de la position du récepteur, trois sources d'erreur peuvent compromettre la précision de cette distance. Pour un système de localisation basé sur la métrique temporelle, elles sont liées respectivement à sa largeur de bande, son seuil de détection, et à l'obstruction éventuelle du trajet direct. L'implémentation d'un mécanisme de contrôle d'intégrité s'annonce alors comme une solution prometteuse pour améliorer les performances de notre système. Ce dernier consiste à identifier les mesures aberrantes ne répondant pas aux contraintes imposées par l'application, puis de les exclure ou les corriger en fonction de la stratégie adoptée par le récepteur. Dans ce contexte, nous proposons d'exploiter la diversité spatiale d'un système SIMO (pour Single Input Multiple Output) à deux antennes de réception afin d'identifier les conditions de propagation du canal. La première étape de notre approche a pour but d'augmenter la résolution temporelle des deux réponses impulsionnelles du système. Ces dernières, étant parcimonieuses, sont reconstruites dans le domaine fréquentiel sur une très large bande grâce à une technique de « compressed sensing ». Elles sont ensuite classifiées selon un critère temporel. Celui-ci représente la différence des temps de propagation du signal dans chacun des deux canaux, et il est obtenu par l'inter-corrélation des réponses impulsionnelles reconstruites. L'approche proposée permet alors non seulement d'améliorer la fiabilité de l'information de localisation dans le tunnel, mais également de réduire l'erreur liée à la bande limitée du système et à l'absence du trajet direct. Une implémentation expérimentale de la chaîne de localisation basée sur des signaux OFDM donne lieu à des erreurs d'estimation de distance au moins six fois inférieures à celles reportées par l'approche classique, ou même à celles relatives aux autres techniques d'identification basées sur les tests statistiques. Cet algorithme constitue alors, avec le modèle hybride du canal, les deux contributions majeures de ce travail de thèse. System level simulations are crucial in the development phase of any emerging wireless technology. It allows to identify the key factors that affect the transmission quality and to define the network limits. The used simulators must then be based on accurate and realistic channel models to better predict the system performances. In this context, several researches had been interested to the development of new models that take into account the emerging propagation scenarios introduced by the fifth generation of mobile communications (5G) that will be commercialized by 2020. In order to optimize the spectral and energetic resources use, the mobile terminals of this next generation should be constantly aware of their environment. This relies on the implementation of a location system, especially in constrained environments where satellite positioning systems are not available. In the field of transport, a rather recurrent example of these scenarios is that of tunnels. Although they are indoor environments, this type of environment is characterized by the phenomenon of wave guiding due to its geometric structure and the properties of the materials of its walls. Thus, an extension of the propagation models developed for the 5G systems is then necessary, in order to take into account this use case. We propose in this thesis a hybrid approach to reproduce the effect of the channel in a localization system. First, we calculate the propagation parameters by a ray-tracing simulator. It accurately describes the behavior of the radio waves inside the tunnel, nevertheless, it is expensive in terms of computing time. Then we analyze the obtained deterministic data to identify their statistical laws, and we store both of them in a database to stochastically generate the channel coefficients needed for our ranging system, namely the amplitude and the delay relative to each path. The impulse response of the channel will finally be used to estimate the distance between the two transmission antennas. Depending on the propagation conditions as well as the position of the receiver, three sources of error can compromise the accuracy of this distance. For a ranging system based on the time metric, they are related to the bandwidth, the detection threshold, and the obstruction of the direct path. The implementation of an integrity control mechanism seems to be a promising solution to improve the performance of our system. It then consists of identifying the outliers that do not meet the constraints imposed by the application, then excluding or correcting them according to the strategy adopted by the receiver. In this context, we propose to exploit the spatial diversity of a SIMO (Single Input Multiple Output) system with two reception antennas in order to identify the propagation conditions of the channel. The first step of our approach aims to increase the temporal resolution of the two impulse responses of the system. Being sparse, they are reconstructed in the frequency domain over a very wide band using a compressed sensing technique. Then we classify them according to a temporal criterion, which represents the time difference of propagation of the signal in each channel, and we obtain it by the inter-correlation of reconstructed impulse responses. The proposed approach not only improves the reliability of the ranging information in the tunnel, but also reduces the error related to the limited bandwidth of the system and the obstruction of the direct path. An experimental implementation of the ranging system based on OFDM signals gives rise to distance estimation errors at least six times lower than those reported by the classical approach, or even to those issued from other identification techniques based on statistical tests. This algorithm and the hybrid model of the channel are then the two major contributions of this thesis work.

As a rapid, inexpensive and accurate analysis technique, vis–NIR spectra has shown great advantages for determining a wide variety of soil properties, such as soil organic matter content, mineral composition, water content, particle size and color. Thus, this technique is becoming increasingly popular in soil science. We aim to assess the applicability of using vis–NIR spectra to estimate eighteen different soil properties that are important for Chinese Soil Taxonomy (CST). In this study, vis–NIR reflectance spectra were measured under laboratory conditions. First, partial least-squares regression (PLSR) was used to predict the following soil properties related to soil classification: coarse crumb, sand, silt, and clay contents, bulk density (BD), pH (H2O), pH (KCl), soil organic matter (SOM), total nitrogen (TN), total potassium (TK), and total phosphorus (TP) contents, cation exchange capacity (CEC), free iron (Fe2O3), soluble salts (salt), available phosphorus (AP), exchangeable aluminum (ExAl), aluminum saturation (AS) and base saturation (BS). Then, the important bands for modeling these soil properties were selected based on the selectivity ratio (SR). Finally, the spectral chromophores of the soil and the correlations of soil properties were analyzed. The results showed that (1) the prediction accuracy based on the PLSR algorithm was good for pH, SOM, TN, Fe2O3, salt, AS and BS (RPD > 2.0, R2 between 0.70 and 0.90). For sand, silt, clay, BD, TP, TK, CEC, AP and ExAl, the PLSR model could achieve acceptable estimates (1.4

Article issu de la conférence intitulée « Manuscripts in the making : art and science » qui s'est tenue à Cambridge en décembre 2016.; International audience; Comparing information from the ancient texts about the illumination of the manuscripts to the analysis of the components used to create colour in illuminations sheds interesting light. Our research team studied several manuscripts from the Carolingian era issued from different sources including: the Gospels of St Riquier kept in the library of Abbeville (ms. 4), two Theodulphe’s Bibles, (Orléans-Fleury, BnF lat.11937 and BnF lat.9380), the Godescalc Evangelistary (BnF NAL 1203), the Gospels of St Denis (BnF lat.9387) and the Gospels of St Médard de Soissons (BnF lat.8850), the last three from the court of Charlemagne, and all preserved at the French National Library. These most luxurious manuscripts were written and illuminated between the late eighth century and the first quarter of the ninth century. Through non-destructive portable visual and spectrometric analysis, our research team was able to identify the palette of materials used in scripts and illuminations and especially highlighted the amazing use of Egyptian blue in a very specific part of the illumination in the Godescalc Evangelistary. Our team also found that some substitutes including folium had been used instead of Tyrian purple for the decoration and to dye the parchment. These manuscripts, produced at the initiative of various patrons during Charlemagne’s reign, reveal in the light of the material analysis and the reconstitutions’ experiments by professional illuminators their differences and, beyond, the artistic diversity of this very particular period called the Carolingian Renaissance.

L'application de la connaissance des services écosystémiques rendus par les sols passe par leur meilleure connaissance dans des contextes divers. La Guyane cherche à allier un développement local à un maintien des services environnementaux rendus par les écosystèmes. La déforestation, lorsque pratiquée hors de cahiers de charges bien établis, conduit à la destruction partielle ou totale de l'horizon de surface des sols, donc au principal réservoir de carbone (C) des sols. La connaissance actuelle du carbone des sols de Guyane est limitée. Les données collectées ici permettent d'approcher la spatialisation des contenus de C même si la variabilité des stocks reste forte. Les modélisations du devenir des stocks de C suite à la déforestation ont été réalisées à partir des données collectées dans le projet CarSGuy et le site expérimental de Terres Inovia ; s'ajoutent à ces valeurs la compilation de données issus de campagnes précédentes : Réseau de Mesures de la Qualité des Sols (RMQS) et ValSol. Ces modélisations indiquent l'importance de la prise en compte du stock initial (T0) pour le devenir des stocks. Enfin ce travail a testé une méthodologie de mesures spectrales (visible et proche infra-rouge) de terrain des sols pour l'évaluation du stock. Les données collectées à partir de 236 sites permettent de quantifier et spatialiser les stocks (0-0,3/0-0,5/0-1 m). La modélisation permet de constater que la mise en culture induit de fortes baisses des stocks, 16 % du stock initial à court terme (~ année) après défriche. L'essai expérimental du site de Combi, montre que les stocks ont tendance à croître avec la mise en place d'une prairie de fauche intensive (Urochloa ruziziensis). Enfin, l'étude méthodologique de mesure du stock par spectroscopie-spectrométrie sur le terrain n'a pas été concluante, car testée sur un échantillon à forte diversité pédologique.

We review reviewing our experience of point-of-care and mass spectrometry in Senegal as two disruptive technologies promoting the rapid diagnosis of infection, permitting better medical management of patients.

The review presents the different methods for detecting and quantifying proteins in milk and dairy products. This includes, the determination of total protein from nitrogen analysis, dye-binding methods, infrared spectroscopy. Furthermore, a description of the methods for the detection and/or quantification of individual proteins (caseins, whey proteins) is also provided. This includes gel and capillary electrophoresis, liquid chromatography, mass spectrometry and immunoassays.

Accurate estimation of the terrestrial latent heat flux (LE) for each plant functional type (PFT) at high spatial and temporal scales remains a major challenge. We developed a satellite-based hybrid algorithm to determine the Priestley–Taylor (PT) parameter for estimating global terrestrial LE across multiple biomes. The hybrid algorithm combines a simple empirical equation with physically based ecophysiological constraints to obtain the sum of the weighted ecophysiological constraints (f(e)) from satellite-based normalized difference vegetation index (NDVI) and ground-measured air temperature (Ta), relative humidity (RH), vapor pressure deficit (VPD) and LE for 2000 to 2009 provided by 240 globally distributed FLUXNET eddy covariance (ECOR) tower sites. Cross-validation analysis indicated that the optimization at a PFT level performed well with a RMSE of less than 0.15 and a R2 between 0.61 and 0.88 for estimated monthly f(e). Cross-validation analysis also revealed good performance of the hybrid-based PT method in estimating seasonal variability with a RMSE of the monthly LE varying from 4.3 W/m2 (for 6 deciduous needleleaf forest sites) to 18.1 W/m2 (for 34 crop sites) and with a R2 of more than 0.67. The algorithm's performance was also good for predicting among-site and inter-annual variability with a R2 of more than 0.78 and 0.70, respectively. We implemented the global terrestrial LE estimation from 2003 to 2005 for a spatial resolution of 0.05°by recalibrating the coefficients of the hybrid algorithm using Modern Era Retrospective Analysis for Research and Applications (MERRA) meteorological data, Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI product and ground-measured LE. This simple but accurate hybrid algorithm provides an alternative method for mapping global terrestrial LE, with a performance generally improved as compared to other satellite algorithms that are not calibrated with tower. The calibrated f(e) differs for different PFTs, and all driving forces of the algorithm can be acquired from satellite and meteorological observations.

Digestibility is a key parameter in the evaluation of feeds; however, the measurements on animals require heavy experimental trials, which are hardly feasible when large numbers of determinations are required - for example, in genetic studies. This experiment aimed at investigating the possibility to predict digestibility from NIRS spectra measured on faeces. A total of 196 samples were available from a digestibility experiment investigating the effects of age and genetic background of Large White pigs fed the same diet, rich in fibre (NDF=21.4% DM). Digestibility of dry matter (dDM), organic matter (dOM), nitrogen content (dN), energy (dE) and apparent digestible energy content (ADE) were calculated, as well as total N content of faeces (N). The faeces samples were submitted to reflectance NIRS analysis after freeze-drying and grinding. Calibration errors and validation errors were, respectively, 0.08 and 0.13% DM for total N in faeces, 0.97% and 1.08% for dDM, 0.79% and 1.04% for dOM, 1.04% and 1.47% for dN, 0.87% and 1.12% for dE and 167 and 213 kJ/kg DM for ADE. These results indicate that NIRS can account for digestibility differences due to animal factors, with an acceptable accuracy. NIRS appears to be a promising tool for large-scale evaluations of digestibility. It could also be used for the study of digestibility of different feeds, after appropriate calibration based on a wide range of feed types.

Description du sujet. Le bilan des nutriments, l'homogénéité des andains ainsi que l'hygiénisation, évaluée par la température, de composts obtenus lors du co-compostage de boues de laiterie et de fumier de bovins ont été étudiés à la demande de l'industrie laitière réunionnaise qui souhaite développer la valorisation agronomique des boues de laiterie en satisfaisant les contraintes règlementaires de l'Ile de la Réunion. Objectifs. Les objectifs de cette expérimentation étaient d'évaluer la faisabilité d'un co-compostage de fumier de bovin avec des boues de laiterie et de statuer sur la qualité du compost produit. Méthode. Trois andains de fumier avec deux doses de boues de laiterie ont été mis en place (sur une base massique) : fumier seul (T), fumier ⅔ + boues ⅓ (B1) et fumier ½ + boues ½ (B2) présentant une densité brute de 305, 566 et 630 kg·m-3 et une porosité libre à l'air de 72 %, 48 % et 42 %, respectivement. Un retournement a été effectué après 21 jours. Le compostage a été prolongé durant 142 jours. Résultats. Les résultats obtenus montrent que les températures des tas atteignent 70 °C après deux jours de compostage et que l'hygiénisation (t > 55 °C) dure 40, 29 et 34 jours pour les andains T, B1et B2, respectivement. L'andain T a perdu 69 % de sa masse et 64 % de son volume initial pendant le compostage, l'andain B1, 71 % et 44 % et l'andain B2, 68 % et 49 %, respectivement. Les matières minérales et les éléments fertilisants se sont concentrés dans la matière sèche (MS). L'andain T a perdu 54 % de sa matière organique (MO) et 15 % de son azote (N), l'andain B1, 51 % et 42 % et l'andain B2, 56 % et 50 %, respectivement. Les teneurs en MS et en N deviennent plus homogènes au sein du tas pour les andains T et B1 contrairement au tas B2. Conclusions. Les composts obtenus sont conformes à la norme NFU 44-51 (T) et à la norme NFU 44-95 (B1 et B2), sauf pour le critère de teneur en MS pour ces derniers. Par rapport au compost de fumier de bovin, le compost avec ajout de boues (⅓) est enrichi (sur une base matière fraiche) en N (+ 15 %), en P (+ 40 %) et appauvri en K (- 20 %).

Voor adequate handhaving van het Cadmiumbesluit Wet milieugevaarlijke stoffen blijkt een snelle bepaling van het cadmiumgehalte in kunststof noodzakelijk. De aangewezen technieken zijn erg tijdrovend. Golflengte-dispersieve rontgenfluorescentie-spectrometrie (WD-XRF) is een geschikte techniek om het cadmiumgehalte te screenen. WD-XRF in combinatie met speciale software om de matrixeffecten te reduceren, maakt het mogelijk een kwantitatieve analyse van elementen in kunststof uit te voeren in circa 20 minuten. De methode is geschikt voor kunststoffen, er zijn geen matrixafhankelijke standaarden vereist. Het gehalte aan cadmium gemeten met de combinatie XRF / Uniquant bedraagt 88 - 110% van het gehalte aan cadmium gemeten met Instrumentele Neutronen Activerings Analyse (INAA).

Betreft de ontwikkeling van gevoelige microkolom HPLC-ESI/MS methoden en technieken voor de analyse van MHC klasse I geassocieerde antigeenpeptiden. De analyse bestaat uit de identificatie van T-cel stimulerende peptiden in MHC elutiemengsels van geinfecteerde celkweekculturen gevolgd door de bepaling van de aminozuurvolgorde (sequentie) van deze peptiden. Elutiemengsels van MHC moleculen kunnen zeer grote aantallen (tot 2000) verschillende peptiden bevatten met sterk wisselende samenstelling afhankelijk van te onderzoeken cellijnen of weefselmateriaal. Beschikbare hoeveelheden van individuele peptiden in dergelijke mengsels voor onderzoek liggen in de femtomol (10 exp. -10) tot picomol (10 exp. -12) range per miljard cellen. HPLC-ESI/MS wordt als de meest geschikte techniek beschouwd voor deze toepassing. In dit onderzoek is microkolom HPLC schakeltechniek ontwikkeld ; de condities zijn aangepast voor een optimale gevoeligheid in ESI-MS. De hiermee behaalde gevoeligheden liggen tussen 10 en 50 fmol voor identificatiedoeleinden (molecuulgewichtbepaling), afhankelijk van aard en soort peptide. Sequentie-analyses vergen circa tien keer grotere hoeveelheden (100-500 fmol/peptide). Dit komt overeen met de hoeveelheden antigeenpeptiden in middelgrote celkweken (10 exp. 10 cellen).

Changes in the carbon (C) and nitrogen (N) compartments that result from the addition of organic material (OM) to the soil are predicted by the transformation of added OM (TAO) model with three parameters: very labile (P′L) and stable (PS) fractions of the OM and the rate of remineralization (kremin) of nitrogen immobilized by microorganisms. We propose relations between P′L, PS, kremin and various chemical groups in the OM identified by their 13C nuclear magnetic resonance (NMR) spectra. The aromatic content increased the predicted PS in accordance with published results. The O-aromatic content also increased PS, but much less so than the aromatic content. The carboxyl content decreased PS and increased P′L as in the TAO model based on infrared spectrometry. The carbonyl content decreased P′L, whereas di-O-alkyl increased P′L. The chemical composition of the population of decomposer organisms did not appear to be homeostatic, but was related rather to the composition of the substrate: kremin was positively correlated with the carboxyl and di-O-alkyl content and negatively correlated with the alkyl content. Solid state 13C NMR spectroscopy gave better predictions of the transformations that resulted from adding OM than biochemical fractionation and near infrared reflectance spectrometry (NIRS). It is fast and non-destructive and provides new insights into the processes that control decomposition for research into waste recycling, agro-ecology and climate change.

Corynebacterium pseudotuberculosis biovar equi is the etiologic agent of ulcerative lymphangitis. To investigate proteins that could be related to the virulence of this pathogen, we combined an experimental passage process using a murine model and high-throughput proteomics with a mass spectrometry, data-independent acquisition (LC-MSE) approach to identify and quantify the proteins released into the supernatants of strain 258_equi. To our knowledge, this approach allowed characterization of the exoproteome of a C. pseudotuberculosis equi strain for the first time. Interestingly, the recovery of this strain from infected mouse spleens induced a change in its virulence potential, and it became more virulent in a second infection challenge. Proteomic screening performed from culture supernatant of the control and recovered conditions revealed 104 proteins that were differentially expressed between the two conditions. In this context, proteomic analysis of the recovered condition detected the induction of proteins involved in bacterial pathogenesis, mainly related to iron uptake. In addition, KEGG enrichment analysis showed that ABC transporters, bacterial secretion systems and protein export pathways were significantly altered in the recovered condition. These findings show that secretion and secreted proteins are key elements in the virulence and adaptation of C. pseudotuberculosis. Collectively, bacterial pathogenesis-related proteins were identified that contribute to the processes of adherence, intracellular growth and evasion of the immune system. Moreover, this study enhances our understanding of the factors that may influence the pathogenesis of C. pseudotuberculosis. Fil: Marques Da Silva, Wanderson. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasil. Institut National de la Recherche Agronomique; Francia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Carvalho, Rodrigo D. De Oliveira. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasil Fil: Dorella, Fernanda A.. Universidade Federal de Minas Gerais; Brasil Fil: Folador, Edson L.. Universidade Federal da Paraíba. Centro de Biotecnologia; Brasil Fil: Souza, Gustavo H. M. F.. Waters Corporation; Brasil Fil: Pimenta, Adriano M. C.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasil Fil: Figueiredo, Henrique C. P.. Universidade Federal de Minas Gerais; Brasil Fil: Le Loir, Yves. Institut National de la Recherche Agronomique; Francia Fil: Silva, Artur. Universidade Federal do Pará; Brasil Fil: Azevedo, Vasco. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasil

Compendium de la journée d’étude organisée par la MSH Val de Loire le 27 septembre 2017 dans le cadre du projet APR ECRISA; International audience; L’analyse des encres, dans les documents anciens, est quelquefois le dernier et le seul moyen d’authentifier un document ou de mieux comprendre les chemins de sa transmission. Les techniques d’analyse physico-chimiques qui supposent un prélèvement de matière sur le document sont admissibles pour des documents modernes, dans des contextes d’expertise judiciaire par exemple, mais elles sont parfaitement inenvisageables lorsqu’on parle d’un document patrimonial, a fortiori lorsqu’il s’agit d’un document classé trésor national. Il faut alors recourir à des méthodes respectueuses de l’intégrité du document qui procèdent par stéréomicroscopie, spectro-colorimétrie et fluorescence X. L’exposé a montré les informations que l’on peut tirer de l’application de ce type de méthode à des documents anciens. Menées sur plusieurs catégories de documents, les expériences présentées ont permis de répondre à plusieurs questions intéressant la bibliothèque de Rabelais ou celle de Montaigne. L’exposé présenté a montré successivement les méthodes scientifiques qui peuvent être mises en œuvre et les types de questionnements auxquels ces méthodes peuvent apporter des réponses.

The recent development of new portable devices enables the establishment of NIRS technology at industrial setting (on-line). However, the numerous existing NIRS databases based on a particular parameter, have been constructed with laboratory instruments (off-line), which have required a considerably effort in terms of time, labor and costs. For this reason, the transfer of calibrations between devices of different characteristics is a clearly crucial step. In this study, three different standardization algorithms: Slope/Bias Correction (SBC), Piecewise Direct Standardization (PDS) and Transfer by Orthogonal Projection (TOP) were tested and evaluated for transferring olives quality databases between an off-line NIRS monochromator (FOSS NIRSystem 6500) and a portable NIRS diode-array spectrometer (CORONA 45 visNIR). The results obtained showed that the use of TOP yielded the best Standard Error of Prediction (SEP) values for the fat content (1.97%) and free acidity (2.52%) parameters, while PDS for moisture content (2.24%). These results suggest that good calibration models for quality evaluation in intact olives can be obtained, based on spectral databases transferred between diverses NIRS spectrometers.

Methods are presented testing the suitability of PROSAIL radiative transfer model for analysing HyMap imaging spectroscopy data over grassland. The presented methods include forward modelling and cross-checks of 2D correlation plots. In the forward modelling, it is taken into account that the in situ data are not error free. To increase the predictive power of PROSAIL, a simple and fully automatic feature selection (FS) algorithm is presented identifying and discarding poorly modelled wavebands, yielding more reliable parameter retrievals.

International audience; This book explores different aspects of LA-ICP-MS (laser ablation-inductively coupled plasma-mass spectrometry). It presents a large array of new analytical protocols for elemental or isotope analysis. LA-ICP-MS is a powerful tool that combines a sampling device able to remove very small quantities of material without leaving visible damage at the surface of an object. Furthermore, it functions as a sensitive analytical instrument that measures, within a few seconds, a wide range of isotopes in inorganic samples. Determining the elemental or the isotopic composition of ancient material is essential to address questions related to ancient technology or provenance and therefore aids archaeologists in reconstructing exchange networks for goods, people and ideas. Recent improvements of LA-ICP-MS have opened new avenues of research that are explored in this volume.

Forensic hair analysis can be used as alternative evidence next to body fluids, and to obtain retrospective timeline information of an individual’s drug exposure. Chapter 1 describes the general concepts of drug incorporation into hair, external contamination, and the current status and limitations of hair analysis methods are introduced. Furthermore, an overview of ambient ionization techniques is given, with emphasis on direct analysis in real time (DART). The instrumentation, ionization mechanisms, and application range of DART are presented. Scientific challenges and objectives to improve forensic hair evidence are formulated, which formed the basis of the research presented in this thesis. A major issue in forensic hair analysis is the possibility of false-positive results due to external contamination. In Chapter 2, an evidence-based evaluation of decontamination protocols for the removal of cannabinoid contamination is presented, mainly focused on Δ9-tetrahydrocannabinol (THC). Different solvents were extensively tested for their ability to remove cannabinoid contamination originating from cannabis smoke or indirect contact with cannabis plant material. After selection of the most efficient solvents, different sequential wash steps were tested on externally contaminated blank hair samples. Finally, application of the three best performing protocols on cannabis users’ hair, both as such and after deliberate contamination, resulted in removal of all contamination without removing incorporated THC. From the detailed scientific evidence reported in this chapter, a protocol using a single methanol wash followed by a single aqueous SDS solution is recommended to remove external cannabis contamination. A novel approach for the analysis of intact locks of hair consisting of DART combined with high resolution mass spectrometry (HRMS) is developed in Chapter 3. DART–HRMS settings were optimized for the analysis of THC and the accuracy of the probed hair zone was investigated using spiked blank hair samples. Intact locks of hair could be longitudinally scanned without the need of extensive sample preparation, resulting in analysis times of only minutes. Detection of THC was achieved in several hair samples from cannabis users. A quantitative liquid chromatography (LC)–MS/MS method was developed, in-house validated, and used to confirm the presence of THC in drug user hair samples. With a retrospective timeline accuracy of ±2 weeks, a significant improvement over conventional segmented hair analysis was achieved. Moreover, differentiation between zones of different THC content within a DART hair scan could be made, indicating possibilities for retrospective assessment of time of drug use. The DART hair scan method has been improved and expanded in Chapter 4. Targeted detection of four commonly used drugs of abuse (amphetamine, cocaine, MDMA and THC) with structural confirmation was achieved by data-dependent product ion scans. Simultaneously, full-scan high-resolution data was obtained and retrospectively interrogated versus a list of more than a hundred, less common, drugs of abuse and occasionally abused pharmaceutical drugs. The hair scan method was validated for the analysis of cocaine against an accredited LC–MS/MS method and the detection limit for cocaine was found to comply with the cut-off value of 0.5 ng/mg. Hair samples of 10 different drug users were analyzed. Next to detection of the four targeted drugs of abuse, retrospective data interrogation revealed several additional hits. The detected substances correlated well with reported drug use and by the detection of several metabolites, drug use could be unambiguously proven. The retrospective timeline accuracy was further improved by use of a high spatial resolution DART exit cone, which yielded a DART spot size corresponding to approximately 10 days of hair growth. When direct and/or ambient ionization techniques are used to analyze intact hair samples, endogenous isobaric ions can overlap with compounds of interest and yield false-positive results. The selectivity of four MS instruments with different mass analyzers (orbitrap, quadrupole orbitrap, triple quadrupole, time-of-flight) was evaluated in Chapter 5 by DART analysis of THC from hair samples. To avoid overlap of THC with isobaric ions originating from the hair matrix, a mass resolution of at least 30,000 FWHM was necessary. The use of travelling wave ion mobility spectrometry (TWIMS) resulted in increased selectivity by separation of isobaric ions based on their drift times. A triple quadrupole instrument in multiple reaction monitoring (MRM) mode was found to have the best sensitivity, however, the used transitions were not specific enough for use on drug user hair samples. Thus the selectivity needed to indisputably differentiate THC from endogenous isobaric ions in drug user hair samples could only be achieved by the high resolution of the tested orbitrap MS instruments. Chapter 6 demonstrates the application of forensic hair analysis techniques to veterinary control. Timeline information could be obtained from veterinary hair samples. For this purpose, a UPLC–MS/MS hair analysis method was adapted and optimized for smaller sample sizes. After validation of the method, segmented hair samples obtained from clenbuterol-treated calves using the forensic hair sampling protocol were analyzed and clenbuterol concentration profiles along the hair samples could be obtained. Assessment of the average growth rate of calf tail hair enabled retrospective determination of time of clenbuterol administration. The estimated time of administration was reproducible when analyzing sub-samples taken from the same lock of hair and duplicate locks of hair, and in good correlation with the actual treatment. Through the research presented in this thesis, novel approaches in hair analysis have been developed and the value of forensic hair evidence improved considerably. In Chapter 7, the main achievements of this thesis are discussed in detail and an insight in the future perspectives of hair analysis and ambient ionization is given. Potential further applications of the DART hair scan method, and ambient ionization in general, are presented, including some preliminary results of new decontamination strategies, hair analysis possibilities, and other forensic uses of DART ionization.

The accurate determination of archaeological glass sample composition is challenging due to possible heterogeneity and post-production chemical alteration. Here, depth profiling using the time resolved signal generated by LA-ICP-MS (DP-LA-ICP-MS) is applied to two case studies. The first study concerns corroded Late Bronze Age glass beads. While many varieties of ancient glass beads are corrosion resistant, some recipes are particularly impacted by devitrification, and depth profiling allows for analysis of un-corroded material reflecting original glass composition. In the second case study on a seventeenth century composite glass vessel, depth profiling allowed for measurement of composite layers including a thin ruby gold glass layer and white opaque glass filigree embedded in colorless lead glass. The minimal destructiveness of this technique combined with other advantages of LA-ICP-MS—the large number of elements that can be measured and low detection limits—make this technique ideal for analysis of many kinds of compositionally complex glass objects.

Poster issu de la conférence intitulée « Manuscripts in the making : art and science » qui s'est tenue à Cambridge en décembre 2016.; International audience

International audience; The comprehension of metal homeostasis in plants requires the identification of molecular markers linked to stress tolerance. Proteomic changes in leaves and cambial zone of Populus tremula×P. alba (717-1B4 genotype) were analyzed after 61 days of exposure to cadmium (Cd) 360 mg/kg soil dry weight in pot-soil cultures. The treatment led to an acute Cd stress with a reduction of growth and photosynthesis. Cd stress induced changes in the display of 120 spots for leaf tissue and 153 spots for the cambial zone. It involved a reduced photosynthesis, resulting in a profound reorganisation of carbon and carbohydrate metabolisms in both tissues. Cambial cells underwent stress from the Cd actually present inside the tissue but also a deprivation of photosynthates caused by leaf stress. An important tissue specificity of the response was observed, according to the differences in cell structures and functions.