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Development of a new high-yield integration site assay reveals disease-specific patterns across HTLV-1-associated pathologies
No full textInternational audienceHuman T lymphotropic virus type 1 (HTLV-1) chronic infection is maintained through mitotic proliferation of the infected CD4+ T cells, where the viral genome is integrated as a provirus in its host genome. HTLV-1 integration sites (ISs) have a part in HTLV-1-associated pathologies, with distinct IS patterns associated with malignant proliferation or inflammatory diseases. However, IS determination remains challenging because most assays rely on complex biological and biocomputing protocols. We present an IS assay that solely relies on PCR and Sanger sequencing, which allowed HTLV-1 IS determination in four patients with various HTLV-1-associated pathologies. We adapted an IS assay derived from a panhandle PCR, with several modifications to increase yield. Absence of bias regarding IS retrieval was confirmed using TCRγ clonality. IS analysis was performed in four HTLV-1-positive patients: two with polymyositis, one with adult T-cell leukemia/lymphoma (ATLL), and one with HTLV-1-associated myelopathy (HAM). Overall yield was around 20%, with a mean sequence length downstream the IS of 336 ± 230 bp (range, 44-1,024 bp). There was no major bias in clonal determination, as IS results matched clonality assessed using a TCRγ assay. The IS assay revealed distinct clonal patterns depending on HTLV-1 pathology: dominated by a large clone for ATLL, oligo-or polyclonal for polymyositis and polyclonal for HAM. As a conclusion, we present an easy-to-implement integration site assay for HTLV-1 that allows a relatively unbiased IS analysis regarding clonal populations. This assay could be useful to further explore IS involvement in HTLV-1 associated pathologies
Modulation of marine bacterial adhesion on ultra-soft cross-linked chitosan coatings
No full textInternational audienc
Impact of flax fibre kink-bands on local longitudinal mechanical properties and cell wall ultrastructure
No full textInternational audienceAtomic Force Microscope (AFM) in mechanical mode, Raman and Second Harmonic Generation (SHG) microscopy were applied to explore the ultrastructure and nano-mechanical properties of kink-band regions in flax fibres. It is evidenced, that the longitudinal indentation modulus drastically drops (between −43 and −53%) in kink-band regions, mainly explained by pronounced changes in microfibrillar angle (MFA), from 0 to 6° to 19-21°. At contrary, Raman investigations demonstrate a conservation of biochemical composition, along with a decrease in local crystallinity (between 11 and 57%), contributing also to the mechanical loss in kink-band regions. These micro-scale investigations provide inedited findings about the kink-band features and specificities, especially in term of local properties
Virtual forming based on model calibration from heterogeneous tests
No full textInternational audienceAbstract. This study focuses on calibrating a mechanical model for a DP600 steel using both quasi-homogeneous and heterogeneous tests. Several sample geometries subject to a uniaxial load were selected and tested experimentally, and a finite element model updating method was used to identify the material parameters of an anisotropic plasticity model, leading to several material parameter sets. Then, the virtual forming of cylindrical cup is considered, using these different parameter sets. The strain and stress states of the mechanical tests used for the model calibration are compared with those of the forming process, to analyse their relevance. The main goal is to check the whole chain from the indicator-based design of heterogeneous tests up to a numerical case study of the forming of cylindrical cups
‘“Love, liberty, and loyalty”: unearthing the Defenders’ popular project for the ‘Republic of the United States of France and Ireland’ (1795–6)
No full textInternational audienceWhen Theobald Wolfe Tone arrived in France in February 1796, intent on securing French help to win Irish independence from England and to establish a republic in Ireland, his greatest challenge was not to convince the Directory to launch an expedition to Ireland, but in persuading them that the Irish were mature enough to become republicans and were not mere Chouans. Was Tone deluded and did he embellish the revolutionary potential of the Irish, especially the secret society of the Defenders, as the dominant (revisionist) historiography claims? A close look at the available sources, and a new reading against the grain, or under a ‘satanic light’, of the available sources, allows us to better delineate what could have been an Irish republic or, at least, to situate the Defenders within an Atlantic context of popular politicisation – the ‘Atlantic Republic’
Outer Shelf 3d Geomorphological Features in the Plio-Pleistocene of the Brazilian Equatorial Margin: Depositional System Driven by 405 Kyr Cyclicity
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On angular and volumetric interactions in elastic cubic lattices
No full textInternational audienceAbstract This paper investigates statics and natural vibration of linear elastic cubic lattices, together with their continuum approximations. The lattice endowed with central and angular interactions, referred to as Gazis et al . ’s, is considered first: since the stiffness of each lattice phase must be positive, the equivalent macroscopic Poisson’s ratio must be lower than its central limit 1/4. A volumetric interaction based on a volume-dependent internal pressure is introduced as an additional non-central interaction for a complete calibration of the equivalent Poisson’s ratio up to its incompressibility limit 1/2. This volumetric interaction can also be classified as Fuchs-type, providing a potential energy that depends on the volume variation of each cell. The mixed differential-difference equations of the associated lattice derive from Hamilton’s principle applied to the discrete energies. The algebraic properties of the stiffness matrix of the discrete cell provide information on the positive definiteness of the potential energy, for each lattice with central and non-central interactions. The convergence of this finite lattice towards a linear elastic continuous right parallelepiped is shown in several static loading schemes. The discrete Lamé problem for the free vibration of this parallelepiped is solved for all the considered lattices. It is concluded that discrete and continuum elasticity can be connected by this cubic lattice within a complete range of elasticity parameters
Quel fédéralisme pour l’Europe? (conférence-débat)
No full textconférence-débat organisée en partenariat avec la Maison de l’Europe Morbihan Bretagne Sud et le Mouvement Européen MorbihanInternational audienceconférence-débat organisée en partenariat avec la Maison de l’Europe Morbihan Bretagne Sud et le Mouvement Européen Morbiha
