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Étude de maturités du castets et définition d’un profil aromatique du cépage
No full textIn order to produce high-quality wines while adapting to current climate challenges, the Château has undertaken the overgrafting of castets vines. This initiative aims to assess whether this grape variety can withstand climate changes while enhancing Château La Lagune’s range with a little-known Bordeaux variety. The aim of the study carried out during the internship was to learn more about the castets and analyse their potential to determine the type of wine they can produce. To achieve this, the castets grapes were harvested in two stages, corresponding to two levels of ripeness, to study their behavior during fermentation and analyze the composition of the resulting wine. Both batches were vinified using identical processes to ensure a reliable comparison.Dans le but de produire des vins de qualité tout en s'adaptant aux défis climatiques actuels, le Château La Lagune a entrepris de surgreffer des plants de castets. Cette initiative vise à évaluer si ce cépage est capable de résister aux changements climatiques tout en enrichissant la gamme du Château grâce à un cépage bordelais méconnu. L'objectif de l'étude menée pendant le stage était d'approfondir les connaissances sur le castets et d'analyser son potentiel pour déterminer le type de vin qu'il peut produire. Pour ce faire, le castets a été récolté en deux temps, correspondant à deux niveaux de maturité, afin d'étudier son comportement lors de la fermentation et d'analyser la composition du vin obtenu. Les deux lots ont été vinifiés selon des procédés identiques pour garantir une comparaison fiable
Selective Chemo‐Divergent Hydrogenation of Ethylene Carbonate Enabled by Multi‐Functional Poly(Ionic Liquids)‐Stabilized Ru Nanoparticles
No full textInternational audienceCyclic carbonates, in particular ethylene carbonate (EC), are pivotal compounds across chemical sciences because of their unique properties. Although, their transformation into valuable products has attracted great attention, efficient and selective transformations remain challenging. In this work, we report a catalytic system composed of Ru nanoparticles (RuNPs) stabilized by poly(ionic liquids) (Ru@PIL), that enables the selective chemo-divergent hydrogenation of EC into either EtOH and CO2 or EG and CH4, under solventfree conditions. Those transformations relied on the multi-task ability of poly(ionic liquids) (PILs), which provides efficient electro-steric protection of the NPs, good solubility in neat carbonates, and organocatalytic activity depending on the nature of the PIL counteranions. Hence, PIL incorporating nucleophilic anions, such as I -, triggers the cascade transformation of EC into EtOH via a sequential decarboxylation-hydrogenation process. Conversely, in the presence of non-nucleophilic anions, the PIL is catalytically a spectator, yielding to the "direct hydrogenation" of EC by the RuNPs
Approcher la philosophie par ses gestes
No full textInternational audienceL’article s’interroge sur la pertinence d’une démarche consistant à lire la philosophie comme un ensemble de gestes caractéristiques et transmissibles. Il tente d’abord de comprendre l’actualité de cette notion de geste, puis d’en définir le sens, en la distinguant de notions connexes comme celles d’acte, de posture ou de méthode philosophiques. Il examine ensuite les limites et la pertinence de la métaphore du geste philosophique pour en déjouer les pièges et en évaluer l’intérêt pour penser ce que font les philosophes et convoque la notion d’hypergeste empruntée à Yves Citton pour approfondir l’analyse. En conclusion, il propose quelques pistes illustratives et des prolongements possibles
Partial Detectors Versus Replication To Cope With Silent Errors
No full textInternational audienceThis work studies an iterative algorithm running on an errorprone platform, where silent errors strike each iteration with some probability. A detector verifies correctness before taking a checkpoint but may fail to detect errors. Specifically, an error at iteration I is detected only after iteration (I - 1) + X, where X follows a bounded probability distribution like a truncated geometric distribution. Intuitively, the error silently amplifies during some iterations before it can be detected at distance X or higher, and there is the risk of missing an error that has struck recently but cannot be detected yet. X is bounded by D, the maximum detection latency. To mitigate undetected errors during verification, a simple strategy keeps two checkpoints and divides the execution into D - 1 iteration segments, each followed by verification and checkpoint. In steady state: (i) if verification succeeds, the oldest checkpoint is erased and replaced; (ii) if it fails, rollback occurs to the oldest verified checkpoint. This work explores whether this scheme outperforms replication and determines the optimal number of checkpoints and segment lengths, both theoretically and via Monte Carlo simulations
Using virtual reality for enhancing neuroanatomy learning by optimizing cognitive load and intrinsic motivation.
No full textInternational audienceThis research investigates the effectiveness of virtual reality (VR) in enhancing neuroanatomy learning among medical students, focusing on optimizing cognitive load, intrinsic motivation, and user experience. A total of 77 s-year medical students participated in the study, which compared traditional video-based instruction with three VR conditions: active, guided, and passive. The results demonstrate that VR significantly improved anatomical learning performance compared to traditional methods, particularly in the passive and active conditions. VR also enhanced intrinsic motivation, reduced extraneous cognitive load, and increased germane cognitive load. Interestingly, the guided VR condition yielded the poorest learning performance, although differences between the VR conditions were not statistically significant. These findings suggest that higher interactivity is not inherently linked to better learning outcomes in VR-based education. The study highlights the importance of balancing interactivity and cognitive load in the design of effective VR learning environments. Overall, VR holds strong potential as an educational tool, but its instructional design must be carefully tailored to support both motivation and cognitive efficiency. Future research should further examine the role of interaction modes and learner expertise in shaping the instructional effectiveness of VR
Insights into the role of the covalent Ni–O bonds in LiNiO 2 positive electrodes: a correlative hard X-ray spectroscopy study
No full textInternational audienceThe interest in Ni-rich layered oxide positive electrode materials has been increasing due to their wide applicability particularly in electric vehicles as high capacity and high energy density electrode materials. However, the Ni–O bond array which builds the overall framework and plays a critical role in the charge compensation mechanism of the material requires deeper understanding. This work presents a correlative approach elucidating the role of the local highly covalent Ni–O bonds in a LiNiO2 (LNO) model material. Pristine and electrochemically obtained LNO positive electrodes are analyzed using ex situ X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) to compare the average and local structural evolution upon Li+ ion de-intercalation. Insights from Ni K-edge X-ray absorption near-edge structure (XANES) and non-resonant Ni Kb X-ray emission spectroscopy (XES) spectra are combined to track the electronic environment of Ni. X-ray Raman scattering (XRS) spectra at the Ni L2,3-edges and O K-edge provide direct bulk electronic information with regard to the interplay between Ni 3d and O 2p states. The overall findings imply that O plays a significant role in the charge compensation process, contributing to the substantial negative charge transfer from the O 2p orbitals, because of the covalency in the Ni–O bonds inside the NiO2 framework within the edge-sharing NiO6 octahedra. The utilization of complementary X-ray spectroscopy techniques clarifies the intricate electronic environment of LNO, which is helpful in understanding Ni-rich positive electrode materials and offering new insights into their covalent nature
Epidemiology of peripheral neuropathies in sub-Saharan Africa from 2000 to 2020: systematic review and meta-analysis
No full textInternational audienceIntroduction: Epidemiological studies on peripheral neuropathy (PN) in sub-Saharan Africa (SSA) have been conducted out in various target populations. This systematic review and metaanalysis aim to present and update available descriptive data on PN in SSA from 2000 to 2020. Methods: Research was performed in indexed databases PubMed (MEDLINE), Web of Science, Google Scholar, Scopus, African Journals Online, and grey literature databases. Studies were selected according to the PRISMA methodology and data were extracted using a collection grid. A meta-analysis with a random-effects model was performed to determine the pooled frequency measures of PNs. Results: Overall, 116 studies were included in this review, comprising 75,227 subjects (59.71% male, mean age range 9-68.8 years). The highest number of studies were conducted in East Africa (n = 47; 40.5%). The pooled hospital frequency of PN was 39.6% ([95% CI: 34.2-45.2], I 2 = 99.32%), the pooled prevalence was 4.30% ([95% CI: 2.50-6.50], I 2 = 97.52%), and the pooled hospital incidence was 15.60% per year ([95% CI: 5.10-29.70], I 2 = 98.78%). Pooled hospital frequency of PN was higher in diabetic patients (50.30% [95% CI: 28.30-66.70], I 2 = 99%) and in Southern Africa (44.30% [95% CI: 27.80-61.10], I 2 = 99%). For using electroneuromyogram as a diagnostic tool, the pooled hospital frequency of PN was 76.80% ([95% CI: 67.30-85.40], I 2 = 67%). The frequency of polyneuropathy subgroup was 34.40% ([95% CI: 29.90-46.90], I 2 = 99.20%). Conclusion: PNs are frequent in SSA and particularly in certain target groups. It is important to improve preventive measures for HIV and diabetes and increase the understanding of risk factors associated with PN
Who Counts as a Whistleblower? Legal and Academic Debates in France and the United States
No full textInternational audienceWho gets to decide who can be labeled as a whistleblower and under which conditions? Recent scholarship has demonstrated that not everyone is granted the status of “valid truth-teller” as gender, race, class, and other dimensions are likely to distinguish whistleblowers. As Lida Maxwell writes concerning Chelsea Manning, “someone who, because she appears queer and improperly gendered, […] cannot be heard as a meaningful, proper public speaker” (Maxwell, 2019). This aspect is a key in whistleblowing accounts, as judicial protection can be granted to those who fit the regulator’s definition. As we already know, whistleblowing is a relational process (Contu, Journal of Management Inquiry 393–406, 2014), and those who listen to whistleblowers take an important part in deciding who and what is meaningful and worth listening to
Representation Learning to Advance Multi-institutional Studies with Electronic Health Record Data
No full textInternational audienceThe adoption of EHRs has expanded opportunities to leverage data-driven algorithms in clinical care and research. A major bottleneck in effectively conducting multi-institutional EHR studies is the data heterogeneity across systems with numerous codes that either do not exist or represent different clinical concepts across institutions. The need for data privacy further limits the feasibility of including multi-institutional patient-level data required to study similarities and differences across patient subgroups. To address these challenges, we developed the GAME algorithm. Tested and validated across 7 institutions and 2 languages, GAME integrates data in several levels: (1) at the institutional level with knowledge graphs to establish relationships between codes and existing knowledge sources, providing the medical context for standard codes and their relationship to each other; (2) between institutions, leveraging language models to determine the relationships between institution-specific codes with established standard codes; and (3) quantifying the strength of the relationships between codes using a graph attention network. Jointly trained embeddings are created using transfer and federated learning to preserve data privacy. In this study, we demonstrate the applicability of GAME in selecting relevant features as inputs for AI-driven algorithms in a range of conditions, e.g., heart failure, rheumatoid arthritis. We then highlight the application of GAME harmonized multi-institutional EHR data in a study of Alzheimer's disease outcomes and suicide risk among patients with mental health disorders, without sharing patient-level data outside individual institutions
