Vers un Urbanisme Participatif Numérique Ludique, l'Exemple de Minecraft.

International audienceCet article vise à interroger le rapport entre culture numérique et processus participatif dans l'aménagement urbain. A travers l’étude de l’initiative Blockbyblock menée par UN-Habitat nous interrogeons l’impact des TIC dans la co-conception de places publiques dans les pays émergents et dans les rapports entre acteurs urbains et citoyens. Cela dans le but de déterminer si la re-spatialisation de la ville à l’ère du numérique ne tient-elle pas plus d’une nouvelle démarche de projet venant questionner et s’insérer dans un espace architectural hybride, à la croisée de l’espace et du cyberespace, que d’expérimentations formelles permises par les logiciels paramétriques ou algorithmiques ? L’article se focalise sur le projet de revitalisation de la place publique de Priština (Kosovo) à l’aide du jeu vidéo Minecraft, détourné en logiciel de CAO, facilitant l’engagement citoyen dans le processus de projet. Ce cas d’étude met particulièrement en avant les liens entre espaces physiques et virtuels, la pertinence de l’utilisation d’outils numériques ludiques dans la co-conception et re-questionne la place de l’architecte/urbaniste dans le cadre d’un projet participatif à l’ère du numérique

Quantum metrology using time-frequency as quantum continuous variables: Resources, sub shot-noise precision and phase space representation

We study the role of the electromagnetic field's frequency in time precision measurements using single photons as a paradigmatic system. For such, we independently identify the contributions of intensity and spectral resources and show that both can play a role on the scaling of the precision of parameter estimation with the number of probes. We show in particular that it is possible to observe a quadratic scaling using quantum mode correlations only and explicit the mathematical expression of states saturating the Heisenberg limit. We also provide a geometrical and phase space interpretation of our results, and observe a curious quantum-to-classical-like transition on scaling by modifying the spectral variance of states. Our results connect discrete and continuous aspects of single photons and quantum optics by considering from a quantum mechanical perspective the role of frequency.Comment: 15 pages, 3 figure

Development of a 3D discrete element method approach to study the evolution of rock cutting mechanism in high depth conditions: application to Vosges Sandstone.

peer reviewedWhile wells reach deeper and deeper targets, understanding the cutting mechanism under confinement is not yet fully mastered. Among the numerical methods used to study this problem, the Discrete Element Method has already shown promising results, but the evolution of rock behavior with confinement is not always considered. This work proposes a calibration method based on UCS and triaxial tests to represent the evolution of rock behavior with confinement. This calibration procedure is implemented on Vosges Sandstone. The rock model failure envelope is built based on further triaxial tests and agrees with the experimental one. Secondly, linear cutting tests under confinement were implemented on the calibrated model. The results are compared to experimental ones. Their good agreement allows the validation of the proposed approach.9. Industry, innovation and infrastructur

CVD and CVI of pyrocarbon from various precursors

International audienceThe control of pyrocarbon (pyC) chemical vapor infiltration (CVI) is a key issue in the processing of high-performance C/C composites with applications in aerospace parts and braking technology. For years, the precise investigation of deposition kinetics and pyC nanometerscale anisotropy has been rehearsed in chemical vapor deposition (CVD) and several variants of CVI with various pore sizes, and using mostly propane, propylene, and methane as source precursors. A literature survey and the analysis of recent experimental data have helped to understand better the role of gas-phase intermediate species in the various nanotextural transitions; a coherent modeling frame, which is suitable for propane, propylene, and methane—the latter having a neatly lower reactivity—has been set up and tested against experimental results from independent teams. The relation between nanotexture and processing conditions is then explained

Influence of deep coal mines on the stability of shallow cavities

peer reviewedWallonia and Hauts-de-France regions encounter complex developments of multi-level mining cavities that may affect the stability of shallower ones. This work focusses on an abandoned room-and-pillar quarry that extracted phosphatic chalk. On the same site, coal was mined out at depths from 200 to 750 m. To evaluate the influence of deep coal mines on the stability of shallow cavities, the geometry of created voids was modelled, integrating the mining sequence. In addition, detailed topographic and structural surveys of the chalk quarry were completed by rock mass quality assessment. Then a finite element geomechanical model combining the room-and-pillar quarry and the longwall mining was created. Specific vertical cross sections were investigated. The model revealed the progressive influence of coal mining on the room-and-pillar quarry as the surface mined out increased. These large models finally provide boundary conditions for local models in which the influence of specific parameters can be investigated.3789 - RISSC - Amélioration transfrontalière de la Prévention et de la Gestion des Risques du Sous-Sol engendrés par les terrains sous-Cavés - Région wallonne9. Industry, innovation and infrastructure11. Sustainable cities and communitie

Faulting and stability in a chalk quarry

peer reviewedFractures and faulting in Chalk result from a brittle tectonic context leading to structures with preferred definitions and geometries. When quarrying, the geometry of the exploitation should account for the directions of major fractures and faults for stability purposes. A systematic structural survey was performed in a Chalk quarry with localization and measurement of geometry (dip, direction) and classification of fractures. Two major faulting directions are identified, with a high dip angle (above 60°) to the South. 136 faults are identified and well distributed throughout the site. Most of them are normal faults but some strike-slip faults clearly appear. Joints are generally vertical with 2 main directions and a regularly spaced. Structural data are first integrated in a three-dimensional geological and geometrical model of the quarry. This model shows, in some places, that the direction of the bench face and structural features are in condition of developing hazardous slope failure. The structural model is then used for building typical 2D geomechanical models of the behaviour of discontinuities that may induce displacements. Several cases are considered depending on dip, direction and joint properties. The quality of the rock mass is assessed by means of the GSI and RQD indices and mechanical properties are modified accordingly. to the influence of saturation is also considered. The combination of structural and mechanical models helps the quarry managers in optimizing the geometry of their exploitation, particularly to manage potential hazardous areas

Chemical characterization of inks in skin reactions to tattoo

Skin reactions are well described complications of tattooing, usually provoked by red inks. Chemical characterizations of these inks are usually based on limited subjects and techniques. This study aimed to determine the organic and inorganic composition of inks using X-ray fluorescence spectroscopy (XRF), X-ray absorption spectroscopy (XANES) and Raman spectroscopy, in a cohort of patients with cutaneous hypersensitivity reactions to tattoo. A retrospective multicenter study was performed, including 15 patients diagnosed with skin reactions to tattoos. Almost half of these patients developed skin reactions on black inks. XRF identified known allergenic metals - titanium, chromium, manganese, nickel and copper - in almost all cases. XANES spectroscopy distinguished zinc and iron present in ink from these elements in endogenous biomolecules. Raman spectroscopy showed the presence of both reported (azo pigments, quinacridone) and unreported (carbon black, phtalocyanine) putative organic sensitizer compounds, and also defined the phase in which Ti was engaged. To the best of the authors' knowledge, this paper reports the largest cohort of skin hypersensitivity reactions analyzed by multiple complementary techniques. With almost half the patients presenting skin reaction on black tattoo, the study suggests that black modern inks should also be considered to provoke skin reactions, probably because of the common association of carbon black with potential allergenic metals within these inks. Analysis of more skin reactions to tattoos is needed to identify the relevant chemical compounds and help render tattoo ink composition safer.Peer reviewe

Toll-like receptor 4 selective inhibition in medullar microenvironment alters multiple myeloma cell growth.

peer reviewedBone marrow (BM) mesenchymal stromal cells (MSCs) are abnormal in multiple myeloma (MM) and play a critical role by promoting growth, survival, and drug resistance of MM cells. We observed higher Toll-like receptor 4 (TLR4) gene expression in MM MSCs than in MSCs from healthy donors. At the clinical level, we highlighted that TLR4 expression in MM MSCs evolves in parallel with the disease stage. Thus, we reasoned that the TLR4 axis is pivotal in MM by increasing the protumor activity of MSCs. Challenging primary MSCs with TLR4 agonists increased the expression of CD54 and interleukin-6 (IL-6), 2 factors directly implicated in MM MSC-MM cell crosstalk. Then, we evaluated the therapeutic efficacy of a TLR4 antagonist combined or not with conventional treatment in vitro with MSC-MM cell coculture and in vivo with the Vk*MYC mouse model. Selective inhibition of TLR4 specifically reduced the MM MSC ability to support the growth of MM cells in an IL-6-dependent manner and delayed the development of MM in the Vk*MYC mouse model by altering the early disease phase in vivo. For the first time, we demonstrate that specific targeting of the pathological BM microenvironment via TLR4 signaling could be an innovative approach to alter MM pathology development

Sustained Immunogenicity of 2-dose Human Papillomavirus 16/18 AS04-adjuvanted Vaccine Schedules in Girls Aged 9-14 Years: A Randomized Trial

Background: We previously reported the noninferiority 1 month after the last dose of 2-dose human papillomavirus 16/18 AS04-adjuvanted (AS04-HPV-16/18) vaccine schedules at months 0 and 6 (2D_M0,6) and months 0 and 12 (2D_M0,12) in girls aged 9-14 years compared with a 3-dose schedule at months 0, 1, and 6 (3D_M0,1,6) in women aged 15-25 years. Here, we report the results at study end (month 36 [M36]).Methods: Girls were randomized 1:1 and received 2 vaccine doses either 6 months (2D_M0,6) or 12 months apart (2D_M0,12); women received 3 doses at months 0, 1, and 6 (3D_M0,1,6). Endpoints included noninferiority of HPV-16/18 antibodies for 2D_M0,6 versus 3D_M0,1,6; 2D_M0,12 versus 3D_M0,1,6; and 2D_M0,12 versus 2D_M0,6; and assessment of neutralizing antibodies, T cells, B cells, and safety.Results: At M36, the 2D_M0,6 and 2D_M0,12 schedules remained noninferior to the 3D_M0,1,6 schedule in terms of seroconversion rates and 3D/2D geometric mean titers for anti-HPV-16 and anti-HPV-18. All schedules elicited sustained immune responses up to M36.Conclusions: Both 2-dose schedules in young girls remained noninferior to the 3-dose schedule in women up to study conclusion at M36. The AS04-HPV-16/18 vaccine administered as a 2-dose schedule was immunogenic and well tolerated in young girls

Laser-Induced Electron Diffraction in Chiral Molecules

Strong laser pulses enable probing molecules with their own electrons. The oscillating electric field tears electrons off a molecule, accelerates them, and drives them back toward their parent ion within a few femtoseconds. The electrons are then diffracted by the molecular potential, encoding its structure and dynamics with angstrom and attosecond resolutions. Using elliptically polarized laser pulses, we show that laser-induced electron diffraction is sensitive to the chirality of the target. The field selectively ionizes molecules of a given orientation and drives the electrons along different sets of trajectories, leading them to recollide from different directions. Depending on the handedness of the molecule, the electrons are preferentially diffracted forward or backward along the light propagation axis. This asymmetry, reaching several percent, can be reversed for electrons recolliding from two ends of the molecule. The chiral sensitivity of laser-induced electron diffraction opens a new path to resolve ultrafast chiral dynamics