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L'Homme aux camélias : relire Dumas fils en déplaçant le « prisme de la prostitution »
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Situations de vulnérabilités en contexte plurilingue dans les espaces francophones
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Monitoring of Riverine Aquatic Vegetation Using Satellite PlanetScope Imagery: Feasibility, Limitations and Prospects
No full textInternational audienceSpectral interference induced by the water and the spatial resolution of many satellite images (≥ 10 m) limit the efficiency of remote sensing for monitoring riverine aquatic plant stands. In this study, the potential of using PlanetScope satellite images (3 m in spatial resolution, ~daily acquisition) for monitoring seasonal and interannual aquatic vegetation surface area was evaluated. Airborne images (≤ 0.2 m) acquired on four dates on three aquatic plant stands were used to create, through visual interpretation, reference maps indicating whether the pixels of each PlanetScope image acquired at ±8 days correspond to aquatic vegetation or nonvegetated aquatic areas. For each PlanetScope image, the green normalized difference vegetation index (GNDVI) was calculated and centred on the mean (GNDVI centred ) to distinguish aquatic vegetation from nonvegetated aquatic areas while minimizing variations in their spectral signature over time. Reference maps from the date when aquatic vegetation was the least developed were used to calculate the GNDVI centred classification threshold. To reduce classification errors from radiometric inconsistencies, the frequency at which pixels of PlanetScope images acquired at ±8 days from airborne images were classified as aquatic vegetation was also calculated. Aquatic vegetation was then empirically defined as pixels with a frequency ≥ 85%. Although the classification of PlanetScope images indicates that low abundances of aquatic vegetation cannot be detected, our results show that large changes in stand surface area can be monitored using a multidate classification threshold, thus providing new opportunities for the monitoring of riverine aquatic vegetation on large scales
Que fait la littérature russe au réalisme magique ? Formes et enjeux du recours au surnaturel dans la prose russe contemporaine
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Comparative endocranial anatomy in the crocodylians Leidyosuchus canadensis and Stangerochampsa mccabei from the upper Cretaceous of Alberta, Canada
No full textInternational audienceAbstract Crocodylians evolved a high variety of rostral morphologies during their evolutionary history, highlighting the strong links between morphological plasticity and environmental and ecological parameters. Two Late Cretaceous alligatoroids, the mesorostrine Leidyosuchus canadensi s Lambe, 1907, and the brevirostrine Stangerochampsa mccabei Wu et al., 1996, from Alberta, Canada, preserve a large groove‐shaped recess on the posterior part of the maxilla that has not been documented in other alligatoroids. Despite the potential phylogenetic and paleoecological significance of this neurovascular feature, internal and endocranial structures remain under‐explored among stem alligatoroids. The endocranial morphology, including the paratympanic sinus system of Leidyosuchus canadensis and Stangerochampsa mccabei , was compared to those of extant crocodylians and of the extinct alligatoroid Diplocynodon ratelii based on computed tomography data. The Cretaceous alligatoroids share endocranial features, such as a posteroventral neurovascular projection of the labiolateral canal that connects to the groove‐like recess at the posterior edge of the maxilla and a paratympanic sinus system most similar to those of small‐bodied and young extant crocodylians, suggesting that these pedomorphic features may reflect the ancestral crocodylian condition. Future phylogenetic studies should consider internal and endocranial characters alike to improve our understanding on the relationships among crocodylians
Symmetries of cosmological perturbations: The residual low-multipole ambiguity
No full textInternational audienceIn cosmology, long-wavelength modes are related to large-gauge transformations (LGT), i.e. changes of coordinates that modify the physical geometry of the cosmological patch. These LGTs stand as bona-fide symmetries of cosmological perturbation theory with various applications, from consistency relations constraining cosmological correlators to non-linear conservation laws in the separate-universe approach. In this work, we revisit LGTs and derive two new results. First, we show that the global symmetries already identified in the literature can be extended to local infinite-dimensional symmetries. The associated generators depend on arbitrary functions of time, and generate low-multipole modes that modify the mean curvature energy and the angular momentum of the patch, demonstrating their physical nature. We propose to interpret these low-multipole soft modes as a new cosmological-frame ambiguity that needs to be fixed prior to evaluating cosmological observables. Second, we demonstrate that the adiabatic cosmological perturbations generated by LGTs deform but preserve all the explicit and hidden Killing symmetries of the background geometry. As such, long-wavelength modes stand as a concrete example of algebraically-special cosmological perturbations of Petrov-type O, and inherit the conformal group as isometries and a set of four deformed Killing-Yano tensors and their associated Killing tensors. This opens the possibility to study their effect on cosmological observables in a fully analytic manner
Optimal Fidelity Estimation from Binary Measurements for Discrete and Continuous Variable Systems
No full textInternational audienceEstimating the fidelity between a desired target quantum state and an actual prepared state is essential for assessing the success of experiments. For pure target states, we use functional representations that can be measured directly and determine the number of copies of the prepared state needed for fidelity estimation. In continuous variable (CV) systems, we use the Wigner function, which can be measured via displaced parity measurements. We provide upper and lower bounds on the sample complexity required for fidelity estimation, considering the worst-case scenario across all possible prepared states. For target states of particular interest, such as Fock and Gaussian states, we find that this sample complexity is characterized by the L 1 -norm of the Wigner function, a measure of Wigner negativity widely studied in the literature, in particular in resource theories of quantum computation. For discrete variable systems consisting of n qubits, we explore fidelity estimation protocols using Pauli string measurements. Similarly as for the CV approach, the sample complexity is shown to be characterized by the L 1 -norm of the characteristic function of the target state for both Haar random states and stabilizer states. Furthermore, in a general black box model, we prove that, for any target state, the optimal sample complexity for fidelity estimation is characterized by the smoothed L 1 -norm of the target state. To the best of our knowledge, this is the first time the L 1 -norm of the Wigner function provides a lower bound on the cost of some information processing task
Who are the healthcare professionals involved in interprofessional team meetings in French multidisciplinary primary care centres? A quantitative analysis of eight centres
No full textInternational audienceBACKGROUND: Interprofessional collaboration is crucial for providing high-quality care to patients with complex conditions in primary care. In France, multidisciplinary primary care centres (MPCC) receive funding if they organise at least 6 interprofessional team meetings (ITM) per year to discuss complex patient situations and collectively define care strategies. It remains unclear how ITM have been implemented in France. This study analyses healthcare professionals’ involvement in ITMs within MPCCs. METHOD: A multicenter retrospective quantitative study in 8 French MPCCs based on the analysis of ITM reports for the period from 2018 to 2019 was conducted. RESULTS: 1733 patients’situations (n = 1733 cases) discussed during ITMs were analysed. The 8 MPCCs were heterogeneous in terms of geographical location, creation date, and size (3 MPCCs with > 20,000 patients followed by more than 60 professionals and 3 MPCCs with < 20 professionals). On average, five healthcare professionals attended each ITM, with huge variations among MPCCs. The nurse-general practitioner (GP) pair was central. At least one GP was present at 89% (n = 1469) and nurses at 38.15% (n = 630) of ITMs. Participation of other professionals was less frequent and varied according to the MPCC. Physiotherapists were present at 7.8% of ITMs, and other healthcare professionals were present at < 6% of ITMs, including pharmacists (3% of ITMs). In some cases, healthcare professionals external to MPCC, particularly those related to mental health, were also involved in ITMs. CONCLUSIONS: Depending on the MPCC, the professionals involved in ITM vary widely, with the nurse-GP pair at the centre. The relative absence of certain professionals needs to be analysed in order to encourage interprofessional working. TRIAL REGISTRATION: Not applicable