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Les enjeux et frontières des médias libres, indépendants et alternatifs locaux dans le Grand Ouest
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Favourable long-term outcomes in selected HER2-Positive early breast cancer patients without pathological complete response after neoadjuvant chemotherapy and trastuzumab: A pre–T-DM1 era cohort study
No full textInternational audienceBackground: Adjuvant trastuzumab emtansine (T-DM1) is the standard treatment for HER2-positive early breast cancer (EBC) patients who do not achieve a pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC). Given the heterogeneity within this population, we analyzed long-term outcomes in non-pCR HER2-positive EBC patients who received adjuvant trastuzumab prior to the availability of the KATHERINE trial results METHODS: This single-center cohort study included all HER2-positive EBC patients treated with neoadjuvant chemotherapy at our hospital between 2006 and 2017. Kaplan-Meier and multivariable Cox regression models were employed to assess long-term invasive disease-free survival (iDFS) and overall survival (OS).Results: This study included 103 patients, of which 67.0 % had a residual tumor size of ypT1, and 57.3 % had no residual tumor in the lymph nodes. The median follow-up was 9.3 years. At 3, 5, and 7 years, the iDFS rates were 78.3 %, 72.2 %, and 69.7 %, and the overall survival rates were 90.2 %, 83.3 %, and 79.8 %, respectively. Multivariate analysis identified ypT<2, ypN0, and estrogen receptor positivity as independent predictors of improved iDFS. Among patients with ypT<2, ypN0, and estrogen receptor-positive disease (34 out of 72 with estrogen receptor positivity), iDFS rates were notably high: 97 % (95 % CI: 91.3-100) at 3 years, and 90.9 % (95 % CI: 81.6-100) at both 5 and 7 years.Conclusion: Patients without a pathologic complete response after neoadjuvant chemotherapy plus trastuzumab represent a heterogeneous group. Those with ypT<2, ypN0, and ER-positive residual disease may still achieve excellent iDFS and OS despite absence of adjuvant T-DM1
Convergence of higher derivatives of random polynomials with independent roots
No full textLet be a probability measure on , and let be the random polynomial whose zeros are sampled independently from . We study the asymptotic distribution of zeros of high-order derivatives of . We show that, for large classes of measures , the empirical distribution of zeros of the -th derivative converges back to for all derivative orders . This includes all discrete measures and a broad family of measures satisfying a mild dimension-nondegeneracy condition. We further establish a robustness result showing that, for arbitrary , even after adding a vanishing proportion of roots drawn from a dimension-nondegenerate perturbation, the derivative zero measures still converge back to . These results break the previously known logarithmic barrier on the order of differentiation and demonstrate that the limiting root distribution is preserved under differentiation of order growing nearly linearly with the degree
New directions for interconnector research: drawing from social sciences and humanities perspectives to explore the Celtic Interconnector
No full textInternational audienceThe current discourse on interconnectors primarily centers on the technical and economic aspects necessary for delivering a stable grid infrastructure powered by renewable sources and for integrating energy markets. This article, therefore, explores opportunities to broaden definitions of energy grid interconnectivity beyond the techno-economic sphere. It considers multidisciplinary perspectives and presents novel exploratory viewpoints from the social sciences and humanities. It examines ideas of interconnection by drawing on the Celtic Interconnector, an Irish-French initiative, to explore the cultural, historical, political, and geographical dimensions of interconnectivity. Insights are derived from two workshops with academics in Ireland and France, encouraging a more contextual understanding of energy interconnections beyond their physical and economic dimensions. The article builds on these insights to set out an agenda for future research and reflect on frames of reference for describing, analysing, and engaging with emerging interconnector processes and the multiple stakeholders involved
Evidence for subglacial flooding in labyrinthine channels on Devon Island, Nunavut, Canada
No full textAbstract. Subglacial drainage systems route glacial meltwater to the ice margin either via efficient, channelized systems or inefficient, distributed systems. The interplay between channelized and distributed drainage systems varies spatially and temporally, governed by meltwater supply and abundance, bed roughness and topography, ice sliding velocity, and ice driving stress. Subglacial channel formation and evolution are therefore affected by variability in meltwater supply to subglacial conduits, and these changes may be recorded in the geomorphology of these channels. The formation of subglacial bedrock channels is attributed to higher energy and/or higher magnitude discharge events, such as the episodic release of meltwater in the form of either subglacial or proglacial floods, in comparison to the energy or discharge required to excavate channels in soft sediment. Common features of landscapes modified by meltwater floods include anastomosing channels and multiple erosive surfaces, wherein the pre-existing drainage system is inundated, resulting in the incision of new channels that reconnect downstream. Devon Island in the Canadian Arctic Archipelago was covered by the thin (<1000 m), cold-to-polythermal based Innuitian Ice Sheet over the course of at least three glacial expansions during the last glacial cycle. Despite this, there is a conspicuous lack of typical glacial landforms, and instead, the inland plateau region of the island is incised by ubiquitous subglacial and lateral meltwater channels. Some sets of bedrock subglacial channels on Devon Island bear a striking resemblance to the morphology of The Labyrinth in Antarctica, which formed by the episodic drainage of a subglacial lake. The characteristics, topology, and morphology of these channels, referred to as 'Labyrinthine channels' hereafter, together with two subglacial channel networks make the focus of this study. We argue that, within both labyrinthine and other subglacial channel networks on Devon Island, the presence of distinct erosional surfaces, anastomosing channels, and profile slope breaks imply formation by short-lived locally intense episodes of erosion. The presence of well-defined erosional surfaces suggests floods progressively incised into lower elevations where meltwater was captured by pre-existing or incipient channels. Moreover, steep contacts between erosional surfaces, termed here as "slope breaks", are similar to fluvial knickpoints and hanging valleys found in other notable landscapes caused by flooding, such as the Channeled Scablands, possibly indicating channel headward erosion in response to pulses of intense erosion. Overall, we suggest that the presence of discrete erosional surfaces implies multiple flooding events, and that changing flow conditions during these events are evidenced by slope breaks. Multiple erosional surfaces, scabland-type landscapes, anastomosing bedrock channels, and hanging valleys with steep slope breaks are not consistent with ice marginal melt, demanding large discharge conditions and pulses of activity, and pointing at subglacial rather than marginal or proglacial environments of formation. This work aids in enhancing the current understanding of the role and dynamics of meltwater drainage systems operating under the cold-to-polythermal based Innuitian Ice Sheet, perhaps shedding light into its retreat dynamics, and bolstering the interpretation of glacial dynamics on Devon Island
Revisiting Cu(I)‐Dppm Chemistry: Bright Thermally Activated Delayed Fluorescence Luminescence, Anion Dependance, Mechanochromism, and Singlet Oxygen Generation of a Dinuclear Cu(I) Homoleptic Complex
No full textInternational audienceThe one‐step syntheses of highly luminescent Cu(I) dimetallic complexes are reported using Cu(I) salts and the commercially available dppm ligand. Three crystalline phases A – C , obtained either with PF 6 − ( A and B : [Cu 2 (μ 2 ‐dppm) 3 ](PF 6 ) 2 ) or TEF − ( C : [Cu 2 (μ 2 ‐dppm) 3 ](TEF) 2 ) anions, display distinct conformations and crystal packings that strongly influence photophysical properties. All phases show intense solid‐state thermally activated delayed fluorescence with room temperature quantum yields of nearly 100%. Emission energies and decay times are modulated by packing effects. Phases A and B exhibit pronounced mechanochromic luminescence upon gentle grinding, while phase C is mechanically insensitive, presumably due to its bulky and flexible counter‐anions. Density functional calculation/time‐dependent density functional calculations suggest that crystal packing impacts the structural molecular relaxation, in agreement with mechanochromic behaviors. In aerated CH 2 Cl 2 , these complexes generate singlet oxygen with quantum yield of up to 30%, highlighting their potential as photosensitizers
Reproduction of Data-Driven Identification on real experimental data
No full textThis document extends the work developed in the PhD thesis of Hachem (2025) through the application of the recommended DDI workflow to real experimental full-field measurements
From the text of the exam to the activities it calls for: the case of the new Baccalauréat Exam
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Enseigner l’histoire et à enquêter historiquement avec une procédure : quelques conditions au changement du cadrage enseignant
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Les savoirs pour enseigner l’histoire: Savoirs didactiques et pratiques pédagogiques
No full textInternational audienceCe livre aborde une préoccupation partagée par les chercheurs et formateurs d’enseignants endidactique : à quelles conditions les savoirs produits par les recherches en didactique peuvent-ils nourrir la formation et la pratique enseignante ?Pour répondre à cette question, les auteurs s’intéressent à la fois à l’activité réflexive du métierd’enseignant d’histoire et aux conditions de son développement en formation. L’originalité de leur perspective réside dans le fait d’aborder la question de la formation des enseignants par le biais de la didactique disciplinaire. Cette focalisation sur l’activité de réflexivité desenseignants d’histoire conduit à des travaux qui esquissent une approche de « didactique de laformation » en histoire.Né d’une démarche internationale, ce livre met les résultats de la recherche en didactique de l’histoire au service de la pratique enseignante