Du biopôle de Gerland à la Cité internationale de Lyon; la difficile transcription territoriale des ambitions internationales d'une ville

En France, le terme de “ Grand projet ”, en matière d'aménagement urbain, a tendance à renvoyer à de grandes opérations ponctuelles: Beaubourg, Grand Louvre, Grande bibliothèque, Stade de France, etc., autant d'opérations exceptionnelles liées à une volonté politique forte - parfois même à celle de marquer un mandat – et le plus souvent points d'ancrage de la requalification d'un quartier. Dès lors le “ grand projet ” peut constituer le point d'appui ou la matérialisation d'un “ projet urbain ” dans son acception politique, qu'il nous semble intéressant d'analyser à la fois d'un point de vue interne, dans son fonctionnent urbain, à l'échelle du quartier ou de la ville, et d'un point de vue externe comme élément d'une métropole régionale ou d'une ville connectée sur l'international. Aussi, la lecture conjuguée des notions de “ grand projet ” et de “ projet urbain ” nous semble particulièrement pertinente pour le double regard qu'offre l'objet face à l'ambitieux projet politique et inversement, pour la matérialisation de ce dernier sous une forme architecturale et urbanistique et comme occasion de mettre en place des dispositifs opérationnels susceptibles de dénouer des conflits locaux. Ainsi le grand projet renvoie aussi bien à la question de la transformation de la ville comme réalité physique qu'à celle de la promotion d'une image, que ce soit celle d'un homme ou d'une ville.Lyon nous paraît alors à même de fournir des illustrations possibles de différents types de grands projets, témoins en leur temps de modes différenciés d'agencement des finalités multiples de l'action publique urbaine et matérialisation de modes de “ penser et de faire la ville ” caractéristiques de leur époque. Au début des années 1980, l'implantation dans le quartier de Gerland de l'Ecole Normale Supérieure Sciences constitue le point de départ d'un processus de requalification d'un vieux quartier industriel, d'une agglomération qui se découvre des ambitions de “ métropole technopolitaine ”. Inversement, à la fin de ces mêmes années, la volonté d'affirmer le statut de “ ville internationale ” de Lyon se traduit par la mise en place de la “ Cité Internationale ” bâtie en lieu et place de l'ancien Palais de la Foire. Ces deux opérations offrent l'occasion de s'interroger sur le rôle des grands projets dans les processus de requalification urbaine, la manière dont ils mobilisent de façons différenciées des acteurs aussi bien publics que privés, leur capacité à renouveler l'image des espaces qu'ils concernent et enfin à porter un projet urbain pour une agglomération

Comparison of conventional and High Velocity Compaction of alumina powders

International audienceCeramic compacts can be usually prepared by uniaxial pressing in a die made of stainless steel, but the pressure applied is limited and density gradients occur in many cases. Recently a new forming method in powder metallurgy, the High Velocity Compaction (HVC) has been applied to ceramic powders. This method is similar to conventional pressing but consists in making an ram falling down at a very high speed to the upper punch. The kinetic energy is converted into a strike that produces a high pressure in a really short time. By controlling the kinetic energy, it is possible to apply a desired pressure that can be extremely high (up to 1 GPa) without any damage for the tool. The aim of the study is to compare the process conditions and the properties of green compacts elaborated by the two methods (conventional and HVC) for a similar forming pressure: forming pressure, green density (homogeneity), pore size distribution of the tablets, and then the sintering behavior, the shrinkage, the final density and microstructure of the ceramic material are studied

Optimized Lysis-Extraction Method Combined With IS6110-Amplification for Detection of Mycobacterium tuberculosis in Paucibacillary Sputum Specimens

Background: When available, nucleic acid tests (NATs) offer powerful tools to strengthen the potential of tuberculosis (TB) diagnosis assays. The sensitivity of molecular assays is critical for detection of Mycobacterium tuberculosis (MTB) in paucibacillary sputum.Materials and Methods: The impact of targeting repetitive IS6110 sequences on the PCR sensitivity was evaluated across mycobacterium strains and reference material. Six lysis-extraction protocols were compared. Next, 92 clinical sputum specimens including 62 culture-positive samples were tested and the results were compared to sputum-smear microscopy, culture, and Xpert MTB/RIF test. Finally, the capacity to detect low MTB DNA concentrations was assessed in 40 samples containing <1.5 × 102 copies/ml ex vivo or after dilution.Results: The lower limit of detection (LOD) using the IS6110 PCR was 107 genome copies/ml (95% CI: 83–130) using MTB H37Rv as a reference strain, versus 741 genome copies/ml (95% CI: 575–1094) using the senX3 PCR. The proportion of recovered MTB DNA after lysis and extraction ranged from 35 to 82%. The Chelex® method appeared as a more efficient protocol among the six different protocols tested. The sensitivity and specificity in clinical sputum samples were 95.1% (95% CI: 90.7–99.6) and 100% (95% CI: 96.2–100.8), respectively. Among 40 samples with low MTB DNA concentration, 75% tested positive for IS6110 PCR, versus 55% using the Xpert MTB/RIF assay (p = 0.03).Conclusion: Laboratory assays based on an efficient MTB lysis and DNA extraction protocols combined with amplification of IS6110 repeat sequences appear as a sensitive diagnostic method to detect MTB DNA in sputum with low bacterial load

The Tara Pacific expedition—A pan-ecosystemic approach of the “-omics” complexity of coral reef holobionts across the Pacific Ocean

Coral reefs are the most diverse habitats in the marine realm. Their productivity, structural complexity, and biodiversity critically depend on ecosystem services provided by corals that are threatened because of climate change effects—in particular, ocean warming and acidification. The coral holobiont is composed of the coral animal host, endosymbiotic dinoflagellates, associated viruses, bacteria, and other microeukaryotes. In particular, the mandatory photosymbiosis with microalgae of the family Symbiodiniaceae and its consequences on the evolution, physiology, and stress resilience of the coral holobiont have yet to be fully elucidated. The functioning of the holobiont as a whole is largely unknown, although bacteria and viruses are presumed to play roles in metabolic interactions, immunity, and stress tolerance. In the context of climate change and anthropogenic threats on coral reef ecosystems, the Tara Pacific project aims to provide a baseline of the “-omics” complexity of the coral holobiont and its ecosystem across the Pacific Ocean and for various oceanographically distinct defined areas. Inspired by the previous Tara Oceans expeditions, the Tara Pacific expedition (2016–2018) has applied a pan-ecosystemic approach on coral reefs throughout the Pacific Ocean, drawing an east–west transect from Panama to Papua New Guinea and a south–north transect from Australia to Japan, sampling corals throughout 32 island systems with local replicates. Tara Pacific has developed and applied state-of-the-art technologies in very-high-throughput genetic sequencing and molecular analysis to reveal the entire microbial and chemical diversity as well as functional traits associated with coral holobionts, together with various measures on environmental forcing. This ambitious project aims at revealing a massive amount of novel biodiversity, shedding light on the complex links between genomes, transcriptomes, metabolomes, organisms, and ecosystem functions in coral reefs and providing a reference of the biological state of modern coral reefs in the Anthropocene

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Du biopôle de Gerland à la Cité internationale de Lyon; la difficile transcription territoriale des ambitions internationales d'une ville

En France, le terme de “ Grand projet ”, en matière d'aménagement urbain, a tendance à renvoyer à de grandes opérations ponctuelles: Beaubourg, Grand Louvre, Grande bibliothèque, Stade de France, etc., autant d'opérations exceptionnelles liées à une volonté politique forte - parfois même à celle de marquer un mandat – et le plus souvent points d'ancrage de la requalification d'un quartier. Dès lors le “ grand projet ” peut constituer le point d'appui ou la matérialisation d'un “ projet urbain ” dans son acception politique, qu'il nous semble intéressant d'analyser à la fois d'un point de vue interne, dans son fonctionnent urbain, à l'échelle du quartier ou de la ville, et d'un point de vue externe comme élément d'une métropole régionale ou d'une ville connectée sur l'international. Aussi, la lecture conjuguée des notions de “ grand projet ” et de “ projet urbain ” nous semble particulièrement pertinente pour le double regard qu'offre l'objet face à l'ambitieux projet politique et inversement, pour la matérialisation de ce dernier sous une forme architecturale et urbanistique et comme occasion de mettre en place des dispositifs opérationnels susceptibles de dénouer des conflits locaux. Ainsi le grand projet renvoie aussi bien à la question de la transformation de la ville comme réalité physique qu'à celle de la promotion d'une image, que ce soit celle d'un homme ou d'une ville.Lyon nous paraît alors à même de fournir des illustrations possibles de différents types de grands projets, témoins en leur temps de modes différenciés d'agencement des finalités multiples de l'action publique urbaine et matérialisation de modes de “ penser et de faire la ville ” caractéristiques de leur époque. Au début des années 1980, l'implantation dans le quartier de Gerland de l'Ecole Normale Supérieure Sciences constitue le point de départ d'un processus de requalification d'un vieux quartier industriel, d'une agglomération qui se découvre des ambitions de “ métropole technopolitaine ”. Inversement, à la fin de ces mêmes années, la volonté d'affirmer le statut de “ ville internationale ” de Lyon se traduit par la mise en place de la “ Cité Internationale ” bâtie en lieu et place de l'ancien Palais de la Foire. Ces deux opérations offrent l'occasion de s'interroger sur le rôle des grands projets dans les processus de requalification urbaine, la manière dont ils mobilisent de façons différenciées des acteurs aussi bien publics que privés, leur capacité à renouveler l'image des espaces qu'ils concernent et enfin à porter un projet urbain pour une agglomération

Building an internal model of friction for the parameterization of arm movement when sliding an object toward a target

International audienc

Evidence for an internal model of friction when controlling kinetic energy at impact to slide an object along a surface toward a target

Although the role of an internal model of gravity for the predictive control of the upper limbs is quite well established, evidence is lacking regarding an internal model of friction. In this study, 33 male and female human participants performed a striking movement (with the index finger) to slide a plastic cube-like object to a given target distance. The surface material (aluminum or balsa wood) on which the object slides, the surface slope (-10°, 0, or +10°) and the target distance (25 cm or 50 cm) varied across conditions, with ten successive trials in each condition. Analysis of the object speed at impact and spatial error suggests that: 1) the participants chose to impart a similar speed to the object in the first trial regardless of the surface material to facilitate the estimation of the coefficient of friction; 2) the movement is parameterized across repetitions to reduce spatial error; 3) an internal model of friction can be generalized when the slope changes. Biomechanical analysis showed interindividual variability in the recruitment of the upper limb segments and in the adjustment of finger speed at impact in order to transmit the kinetic energy required to slide the object to the target distance. In short, we provide evidence that the brain builds an internal model of friction that makes it possible to parametrically control a striking movement in order to regulate the amount of kinetic energy required to impart the appropriate initial speed to the object

Building an internal model of friction for the parameterization of arm movement when sliding an object toward a target

International audienc

Throwing performance is associated with muscular power

The aim of the present study was to test the hypothesis that performance in throwing events is associated with muscular characteristics of both upper and lower limbs. Thirty-eight male throwers volunteered to participate. Bench press and half squat tests were conducted on a guided barbell. The barbell displacement signal was recorded using a kinematic system. Maximal power, corresponding optimal velocity and force (P max S, V opt S, F opt S and P max BP, V opt BP, F opt BP for half squat and bench press, respectively) were extrapolated from the power-velocity relationship. Lower limb stiff ness (K) was determined during maximal hopping. The results demonstrated that P max S and P max BP were correlated with each thrower ' s season ' s best performance (SBP, r = 0.54, p < 0.01 and r = 0.71, p < 0.001, respectively). P max S expressed relative to body mass was not correlated with SBP. K was signifi cantly correlated with SBP ( r = 0.66, p < 0.001). The relationship between P max BP expressed relative to body mass and SBP remained signifi cant ( r = 0.54, p < 0.001). The results of the study suggest that high strength and stiff ness values for lower limbs and strength and velocity characteristics for upper limbs may be associated with athletic throwing performance