83 research outputs found

    Autofluorescence multispectral image analysis at the macroscopic scale for tracking wheat grain tissues: a novel approach for a more specific identification of wheat grain dietary fibre

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    Wheat grain contains about 12-14% of fibres mainly located in the outer layers. The composition and the structure of wheat dietary fibres, as well as the nature and amount of co-passengers, vary according to the tissue where they are originated from. The aleurone layer is rich in low substituted arabinoxylans esterified to ferulic acid whereas outer pericarp contains highly substituted arabinoxylans but also cellulose and lignin. Consequently wheat dietary fibres properties showed a high variability according to their tissue of origin within the grain, which deeply impact their nutritional effects. If the identification of tissues in wheat grain is commonly performed, it remains challenging for food ingredient such as mill streams (flour, bran etc).Equipements are now available to acquire multispectral fluorescence images at the macroscopic scale using filters with specific excitation/emission wavelengths. These fluorescence macroscopes allow obtaining images of a representative number of particles together with a spatial resolution of less than 3 ÎŒm. In such images, the intensities measured for each pixel, though they are not spectra, can be assembled to form spectral profiles. To identify the tissular origin from this information, we propose to develop a prediction model on particles using calibration data coming from the observation of tissue sections. This approach is based on several assumptions. The first one is that the multispectral autofluorescence of plant tissues is specific and the second is that it is possible to measure fluorescence intensities in a reproducible way. The objective of the present work was to check the fluorescence macroscope as an efficient device for measuring and comparing fluorescence intensities.The variability of fluorescence profiles was studied by selecting pixels in cross-section or in particles mounted in air or in water. The statistical variations were studied by principal component analysis and variance analysis. The first effect, mainly described by principal component 1, was to differentiate aleurone layer from pericarp tissue. The second effect, mainly described by component 2, was a difference between the two mounting media. The differences between sections or powders were not correlated to the other factors and were considered as not significant. Our results show that profiles extracted from multispectral images of cross-sections or particles are similar and allow the identification of wheat grain tissues. If implemented, the prediction from cross-section could be less tedious than other methods requiring dissection and lead to the identification of more tissues. We have demonstrated the proof of concept of tracking wheat dietary fibre origin by predicting tissues on images of particles. This method could help to better qualify flours and various milling fractions as well as to control whole grain products

    Chapitre 2. Les jardins de la fin du Ier siĂšcle av. J.‑C. et de la premiĂšre moitiĂ© du siĂšcle suivant

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    Il s’agit des premiers amĂ©nagements Ă©tablis sur le haut de plage constituĂ© par l’épais niveau sableux (fig. 22 et coupe 2a). Comme nous l’avons dĂ©crit prĂ©cĂ©demment, la mer a « reculé » et le rivage se trouve alors plusieurs dizaines de mĂštres plus au sud. Ce niveau, dont la surface marque un faible pendage vers le sud, paraĂźt se stabiliser aux alentours de 0,90/1 m NGF et ne s’exhaussera que trĂšs peu durant les Ă©poques suivantes en raison de son Ă©loignement continu du rivage et donc des appor..

    Characterisation of a non-pathogenic and non-protective infectious rabbit lagovirus related to RHDV

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    The existence of non-pathogenic RHDV strains was established when a non-lethal virus named rabbit calicivirus (RCV) was characterised in 1996 in Italy. Since then, different RNA sequences related to RHDV have been detected in apparently healthy domestic and wild rabbits, and recently a new lagovirus was identified in Australia. We have characterised from seropositive healthy domestic rabbits a non-lethal lagovirus that differs from RHDV in terms of pathogenicity, tissue tropism and capsid protein sequence. Phylogenetic analyses have revealed that it is close to the Ashington strain and to the RCV, but distinct. We proved experimentally that it is infectious but non-pathogenic and demonstrated that, contrary to the other described non-pathogenic lagoviruses, it induces antibodies that do not protect against RHDV. Our results indicate the existence of a gradient of cross-protection between circulating strains, from non-protective, partially protective to protective strains, and highlight the extent of diversity within the genus Lagovirus

    The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to

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    The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria

    The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to

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    The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria

    Ville et campagne de Fréjus romaine

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    En 2006, une fouille d’archĂ©ologie prĂ©ventive, dĂ©signĂ©e sous le nom de « Villa Romana », a Ă©tĂ© rĂ©alisĂ©e dans le quartier de Villeneuve Ă  FrĂ©jus. Durant l’AntiquitĂ© il s’agit d’une zone pĂ©riurbaine situĂ©e entre la ville de Forum Iulii et le dĂ©bouchĂ© de l’Argens. Connu depuis longtemps en raison de la prĂ©sence d’un Ă©difice thermal toujours en Ă©lĂ©vation, le quartier a Ă©tĂ© fouillĂ© Ă  plusieurs occasions et est interprĂ©tĂ© comme Ă©tant l’emplacement du camp de la flotte, Ă©tabli aprĂšs la bataille d’Actium. Celui-ci se transforme progressivement durant le Ier siĂšcle apr. J.-C. en quartier suburbain au fur et Ă  mesure que se dĂ©veloppe Forum Iulii. Le secteur fouillĂ© se situe dans la partie sud du camp, bordĂ©e par la mer durant les premiers temps de l’AntiquitĂ©. La fouille a permis de rĂ©vĂ©ler la prĂ©sence d’une plage amĂ©nagĂ©e. Les terrains ont ensuite Ă©tĂ© rapidement gagnĂ©s sur la mer, en raison d’une avancĂ©e rapide du littoral, que des Ă©tudes rĂ©centes ont permis de bien connaitre Ă  FrĂ©jus. Des jardins y sont alors amĂ©nagĂ©s. A partir du IIe siĂšcle, cet espace est transformĂ© en zone agricole, et constitue l’illustration de l’exploitation de la campagne aux portes de FrĂ©jus, et cela, jusqu’à la fin de l’AntiquitĂ©. S’ensuit une longue pĂ©riode d’abandon de plusieurs siĂšcles, avant que l’espace ne soit Ă  nouveau vouĂ© Ă  l’agriculture et ce jusqu’à l’orĂ©e des annĂ©es soixante. Depuis, le dĂ©veloppement de la ville actuelle de FrĂ©jus a de nouveau transformĂ© ce quartier en zone urbaine. Cet ouvrage, publiĂ© quelques annĂ©es seulement aprĂšs la fouille, prĂ©sente l’ensemble des Ă©tudes archĂ©ologiques et palĂ©oenvironnementales, rĂ©alisĂ©es Ă  l’occasion de cette opĂ©ration, largement pluridisciplinaire. Elles fournissent un contexte environnemental nouveau pour ce quartier antique et permettent de redĂ©finir un paysage Ă  partir d’analyses bioarchĂ©ologiques et palĂ©oĂ©cologiques rĂ©centes. L’étude de l’ensemble des mobiliers archĂ©ologiques est Ă©galement prĂ©sentĂ©e, en suivant la chronologie et l’évolution de ce quartier Ă  travers l’AntiquitĂ© et l’époque moderne

    ModĂšles Ă©conomiques d’un marchĂ© naissant : le livre numĂ©rique

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    Alors que le marchĂ© du livre numĂ©rique est encore balbutiant en France et reprĂ©sente moins de 1% du chiffre d’affaires des Ă©diteurs, les stratĂ©gies commerciales mises en Ɠuvre par les acteurs traditionnels de la chaĂźne du livre et par de nouveaux entrants permettent d’esquisser diffĂ©rentes configurations des marchĂ©s du livre numĂ©rique. La dĂ©matĂ©rialisation induit des mutations qui auront des consĂ©quences sur l’ensemble de la filiĂšre : disparition et apparition d’acteurs, perte, crĂ©ation et dĂ©placement de valeur, restructuration industrielle. Les enjeux de marchĂ©, soumis Ă  certaines contraintes techniques comme celle de l’interopĂ©rabilitĂ© entre normes de fichiers et matĂ©riels de lecture, dĂ©pendent aussi du maintien ou de l’évolution de la lĂ©gislation rĂ©gissant le commerce du livre en France : droits de propriĂ©tĂ© intellectuelle, fiscalitĂ©, mode de fixation du prix. Cette photographie cherche Ă  synthĂ©tiser les futurs possibles de l’économie du livre numĂ©rique

    EVALUATION OF PLANT HISTOLOGY BY AUTOMATIC CLUSTERING BASED ON INDIVIDUAL CELL MORPHOLOGICAL FEATURES

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    A procedure has been developed for the automatic clustering of plant cells observed by confocal microscopy. The contribution of cell morphological features to reveal histological regions has been investigated. Several adjacent images were acquired to visualise a representative region of the sample and a mosaic image was built. The cell size and shape and the cell wall thickness were quantified. The extracted features were used to automatically classify the cells into morphological groups. The technique made it possible to split the cell population into 8 groups mainly corresponding to histological regions of beet root

    Identification of tissular origin of particles based on autofluorescence multispectral image analysis at the macroscopic scale

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    Powders produced from plant materials are heterogeneous in relation to native plant heterogeneity, and during grinding, dissociation often occurred at the tissue scale. The tissue composition of powdery samples could be modified through dry fractionation diagrams and impact their end-uses properties. If tissue identification is often made on native plant structure, this characterization is not straightforward in destructured samples such powders. Taking advantage of the autofluorescence properties of cell wall components, multispectral image acquisition is envisioned to identify the tissular origin of particles. Images were acquired on maize stem sections and ground tissues isolated from the same stem by hand dissection. The variability in fluorescence intensity profiles was analysed using principal component analysis. The correspondence between fluorescence profiles and the different tissues observed in maize sections was assessed based on histology or known compositional heterogeneity. Similar variability was encountered in fluorescence profiles extracted from powder leading to the potential ability to predict tissular origin based on this autofluorescence multispectral signal

    Jean Norton Cru

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    Jean Norton Cru a bouleversĂ© l'historiographie de la Grande Guerre. Son ouvrage majeur, TĂ©moins, qui a suscitĂ© bien des remous dĂšs sa parution en 1929, est devenu une rĂ©fĂ©rence en mĂȘme temps que le prĂ©texte Ă  de nouvelles controverses. HĂ©ros du peuple des poilus dont il aurait restituĂ© la vĂ©ritĂ© pour les uns, il est pour d'autres un critique incapable de comprendre que le tĂ©moignage « vrai » ne dit pas toute la vĂ©ritĂ© de la guerre. De ce chantre du tĂ©moignage, opposant l'histoire d'en bas Ă  l'histoire « officielle », on ne savait pas grand-chose. La publication de sa correspondance de guerre et l'enquĂȘte biographique qui l'accompagne permettent enfin de rĂ©pondre et d'Ă©clairer l'homme et son expĂ©rience de combattant. DĂšs qu'il commence Ă  relater l'Ă©preuve du feu en janvier 1915, il dĂ©nonce les erreurs ou les falsifications qu'il dĂ©cĂšle dans la presse ou dans les ouvrages. Son vĂ©cu, la dĂ©couverte de la guerre rĂ©elle, lui permettent de parler autrement du conflit et des souffrances des soldats. Le projet de TĂ©moins est bien nĂ© dans les tranchĂ©es.« Les lettres constituent la plus petite des cinq classes alors qu'elles devraient ĂȘtre la plus grande
 Les documents de cette classe sont si prĂ©cieux que nous avons, dans TĂ©moins, ajoutĂ© seize recueils trop incomplets aux douze premiers [composĂ©s de la correspondance complĂšte de combattants tuĂ©s]. Ces extraits trop courts sont cependant suffisants pour donner une idĂ©e du tĂ©moignage qu'offrirait la correspondance complĂšte si elle venait Ă  ĂȘtre publiĂ©e, et nous souhaitons vivement qu'elle le soit. Et il faut en Ă©diter d'autres. Il y a en France plusieurs millions de correspondances de guerre dans les tiroirs. Sur cette masse il n'est pas tĂ©mĂ©raire de supposer que quatre ou cinq recueils uniraient la valeur littĂ©raire Ă  la valeur documentaire. EspĂ©rons qu'on les publiera et qu'on les sauvera de la destruction qui les guette. » Jean Norton Cru, Du TĂ©moignage, Paris, Gallimard, NRF, 1930, p. 80-81
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