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La peur de l’au-delà au XVe siècle : Une description turque des enfers
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Acute Promyelocytic Leukemia, Retinoic Acid, and Arsenic: A Tale of Dualities
No full textInternational audienceAcute promyelocytic leukemia (APL) is driven by the promyelocytic leukemia (PML)/retinoic acid receptor α (RARA) fusion oncoprotein. Over the years, it has emerged as a model system to understand how this simple (and sometimes sole) genetic alteration can transform hematopoietic progenitors through the acquisition of dominant-negative properties toward both transcriptional control by nuclear receptors and PML-mediated senescence. The fortuitous identification of two drugs, arsenic trioxide (ATO) and all-trans-retinoic acid (ATRA), that respectively bind PML and RARA to initiate PML/RARA degradation, has allowed an unprecedented dissection of the cellular and molecular mechanisms involved in patients’ cure by the ATO/ATRA combination. This analysis has unraveled the dual and complementary roles of RARA and PML in both APL initiation and cure by the ATRA/ATO combination. We discuss how some of the features unraveled by APL studies may be more broadly applicable to some other forms of leukemia. In particular, the functional synergy between drugs that promote differentiation and those that initiate apoptosis/senescence to impede self-renewal could pave the way to novel curative combinations
Republican Sovereignty
No full textInternational audienceContemporary republican scholars are divided around the concept of state sovereignty, one of the most central concepts of modern political philosophy. This chapter assumes a basic and widely shared definition of sovereignty as ultimate political authority, together with the traditional distinction between internal and external sovereignty. It distinguishes between two main views of internal sovereignty—the classical and revisionist views—and between two main views of external sovereignty—the exclusive and multiple views. The chapter argues that both distinctions are gradual, rather than an all-or-nothing matter; that they should be approached as normative; and that there are no conceptual implications among them. It identifies how republicans have situated themselves in the debate, supporting different combinations of these views, and points out where their main normative disagreements lie. Finally, it articulates a republican argument for a revisionist view of internal sovereignty and a multiple view of external sovereignty
Tuning the BCS-BEC crossover of electron-hole pairing with pressure
No full textInternational audienceIn graphite, a moderate magnetic field confines electrons and holes into their lowest Landau levels. In the extreme quantum limit, two insulating states with a dome-like field dependence of the their critical temperatures are induced by the magnetic field. Here, we study the evolution of the first dome (below 60 T) under hydrostatic pressure up to 1.7 GPa. With increasing pressure, the field-temperature phase boundary shifts towards higher magnetic fields, yet the maximum critical temperature remains unchanged. According to our fermiology data, pressure amplifies the density and the in-plane effective cyclotron mass of hole-like and electron-like carriers. Thanks to this information, we verify the persistent relevance of the BCS relation between the critical temperature and the density of states in the weak-coupling boundary of the dome. In contrast, the strong-coupling summit of the dome does not show any detectable change with pressure. We argue that this is because the out-of-plane BCS coherence length approaches the interplane distance that shows little change with pressure. Thus, the BCS-BEC crossover is tunable by magnetic field and pressure, but with a locked summit
Compressive Raman microspectroscopy parallelized by single-photon avalanche diode arrays
No full textInternational audienceWe demonstrate an efficient and scalable compressive Raman parallelization scheme based on single-photon avalanche diode (SPAD) arrays to reach pixel dwell times of 23 s, representing over 10 speed-up using the otherwise weak spontaneous Raman effect
Une éthique des humains dans la communauté des vivants : d’une question éludée au défi de notre époque
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Itinéraires de la mémoire : les églises de Crète vénitienne au prisme des carnets inédits de Giuseppe Gerola
No full textInternational audienceCet article, à partir des premières pages des carnets de terrain inédits de l’historien Giuseppe Gerola (1877-1938), retrace les premiers pas du chercheur en Crète vénitienne. Missionné par l’Institut vénitien des sciences, des arts et des lettres, le jeune savant parcourt inlassablement l’île de 1900 à 1902, réunissant un matériel d’une ampleur extraordinaire, qui formera le fondement de toute étude postérieure sur le patrimoine vénitien en Crète. En s’appuyant sur les premières pages des carnets, ce sont les premières étapes de l’itinéraire de Gerola qui sont ici reconstituées, en particulier la formation de son regard : nombre d’informations à ce jour inédites figurent dans ces carnets. Première trace conservée de ce riche patrimoine, les carnets s'intéressent aussi à son devenir à travers le temps, puisque Gerola y rapporte également les souvenirs des Crétois liés à la préservation de ces églises pendant la présence ottomane sur l'île. La mémoire y acquiert ainsi une dimension aussi bien patrimoniale qu'immatérielle, qui invite à reconsidérer ces documents, initialement supports de travail, devenus aujourd'hui sources primaires
Nihil obstat: Préface à Pape François, Louée soit la lecture. Lettre sur le rôle de la littérature dans la formation
No full textInternational audienceLire le pape aujourd’hui ? Quelle drôle d’idée ! La nécessité s’en impose pourtant. Je le dis en pesant mes mots, non pas en catholique, non pas en chrétien, mais en fidèle d’une seule religion (plus avouable peut-être en ce bas monde) : la littérature. [...] Si le document pontifical s’adresse par vocation au monde catholique, prêtres, religieux et laïcs, sa portée va bien au-delà. Les professeurs de lettres, les pédagogues et responsables éducatifs de toute obédience, y compris dans l’enseignement non confessionnel, y trouveront de quoi méditer utilement. J’en recommande volontiers la lecture à tous les parents ainsi qu’à tout ministre de l’Éducation nationale, à tous ceux qui lisent ou écrivent et encore davantage à tous ceux qui ne lisent pas et ignorent ce dont ils se privent
Optimal Ti-Substitution in Layered Oxide Cathodes for Na-Ion Batteries
No full textInternational audienceSodium layered oxides NaxMO2 (x ≤ 1 and M = transition metal ions) gain interest as sodium ion battery (NIB) cathodes due to their high energy density and cost-effectiveness. The nature of transition metal ions (M) defines the material properties, and the substitution of M with redox inactive Ti4+ is often seen as beneficial in reducing phase transitions during cycling and thus improving the cycle life. In this respect, our present study focuses on understanding the origin of this improvement by studying the highly substituted P2 Na0.67Ni0.30Zn0.03Mn0.67-yTiyO2 (0 ≤ y ≤ 0.67) phases, based on their electrochemical performance combined with structural analyses and DFT calculations. The results indicate that Ti4+, by increasing the M-O bond ionicity, disrupts the Na+-vacancy ordering at lower voltages (< 4V, until ~60% SOC), reduces the participation of O 2p in the redox process, thereby suppressing Na-removal and the extent of P2-O2 phase transition at high voltages. We show that this effect becomes maximum for y=0.52 (P2 Na0.67Ni0.30Zn0.03Mn0.15Ti0.52O2) and beyond, for which we observe a nearly solid-solution like behavior of P2-type structure. However, the d0 Ti4+ is prone to cation migration leading to poor structural reversibility as observed from operando XRD analyses, making the highly Ti4+-substituted material less suitable for practical applications. An optimum ratio of y= 0.3 (Na0.67Ni0.3Zn0.03Mn0.37Ti0.3O2) is beneficial for cycle life as well as rate capability and the study points the importance of carefully selecting transition metal combinations in finest ratio to achieve the best performing sodium layered oxide electrode materials
