A paradigm for controlling virtual humans in urban environment simulations

Presents a new architecture for simulating virtual humans in complex urban environments. The approach is based on the integration of six modules. Four key modules are used in order to manage environmental data, simulate human crowds, control interactions between virtual humans and objects, and generate tasks based on a rule-based behavioral model. The communication between these modules is made through a client/server system. Finally, all low-level virtual human actions are delegated to a single motion and behavioral control module. Our architecture combines various human and object simulation aspects, based on the coherent extraction and classification of information from a virtual city database. This architecture is discussed in this paper, together with a detailed case study exampl

Differences in anti-malarial activity of 4-aminoalcohol quinoline enantiomers and investigation of the presumed underlying mechanism of action

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Germline bias dictates cross-serotype reactivity in a common dengue-virus-specific CD8(+) T cell response.

Adaptive immune responses protect against infection with dengue virus (DENV), yet cross-reactivity with distinct serotypes can precipitate life-threatening clinical disease. We found that clonotypes expressing the T cell antigen receptor (TCR) β-chain variable region 11 (TRBV11-2) were 'preferentially' activated and mobilized within immunodominant human-leukocyte-antigen-(HLA)-A*11:01-restricted CD8(+) T cell populations specific for variants of the nonstructural protein epitope NS3133 that characterize the serotypes DENV1, DENV3 and DENV4. In contrast, the NS3133-DENV2-specific repertoire was largely devoid of such TCRs. Structural analysis of a representative TRBV11-2(+) TCR demonstrated that cross-serotype reactivity was governed by unique interplay between the variable antigenic determinant and germline-encoded residues in the second β-chain complementarity-determining region (CDR2β). Extensive mutagenesis studies of three distinct TRBV11-2(+) TCRs further confirmed that antigen recognition was dependent on key contacts between the serotype-defined peptide and discrete residues in the CDR2β loop. Collectively, these data reveal an innate-like mode of epitope recognition with potential implications for the outcome of sequential exposure to heterologous DENVs

Effective Ion Mobility Peak Width as a New Isomeric Descriptor for the Untargeted Analysis of Complex Mixtures Using Ion Mobility-Mass Spectrometry

International audienceIon mobility coupled with mass spectrometry was proven to be an efficient way to characterize complex mixtures such as petroleum samples. However, the identification of isomeric species is difficult owing to the molecular complexity of petroleum and no availability of standard molecules. This paper proposes a new simple indicator to estimate the isomeric content of highly complex mixtures. This indicator is based on the full width at half maximum (FWHM) of the extracted ion mobility peak measured in millisecond or square angstrom that is corrected for instrumental factors such as ion diffusion. This value can be easily obtained without precisely identifying the number of isomeric species under the ion mobility peaks. Considering the Boduszynski model, the ion mobility profile for a particular elemental composition is expected to be a continuum of various isomeric species. The drift time-dependent fragmentation profile was studied and confirmed this hypothesis, a continuous evolution of the fragmentation profile showing that the larger alkyl chain species were detected at higher drift time values. This new indicator was proven to be a fast and efficient method to compare vacuum gas oils for which no difference was found using other analytical techniques

Molecular Insights on the Recognition of a Lactococcus lactis Cell Wall Pellicle by the Phage 1358 Receptor Binding Protein

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In situ deformation in T.E.M.: recent developments

In situ deformation tests in T.E.M. are currently performed in our laboratory on different types of material to study their mechanical properties. Recent developments of this technique are presented in this paper. Many examples from our recent works are demonstrated to support this presentation. The procedure of the specimen preparation and the special straining holders are described in details. The validity of the results to explain the behaviour of the bulk materials is discussed with special attention to the stress control and the possible artefacts. The qualitative and quantitative potentialities of this technique are reviewed.Au laboratoire, nous étudions les propriétés mécaniques des matériaux par des expériences de déformation in situ réalisées à l'intérieur d'un microscope électronique en transmission. Dans cet article, nous présentons les développements de cette technique mis au point au laboratoire au cours de ces dernières années. De nombreux exemples issus de nos travaux sont cités en illustration. Nous décrivons le procédé de préparation des échantillons et nos porte-objet de déformation. La validité de ces expériences pour expliquer le comportement du matériau massif est ensuite discutée. Une attention plus particulière est portée sur la façon de contrôler la contrainte et sur les éventuels artefacts liés à cette technique. Enfin, nous faisons une revue des potentialités d'analyses qualitatives et quantitatives que possède cette technique

Viral infection modulation and neutralization by camelid nanobodies

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