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Rural sub-elites in Bronze Age Egypt: evidence and strategies of an elusive social group
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Concentration of the empirical measure in Wasserstein distance: bounds involving the covering dimension
No full textWe give concentration inequalities in Wasserstein distance for the empirical measure of a sequence of independent and identically distributed random variables with values in a Polish space E. These inequalities involve the covering dimension of the support of the distribution of the variables. More precisely, we obtain a complete extension of the concentration inequalities of Fournier and Guillin [2015] in the case where E = R^d , in which the covering dimension replaces the dimension of the ambient space E
Search for a Doubly Charged Scalar at the LHC and FCC-hh
No full textInternational audienceDoubly charged scalars frequently emerge in many well-motivated extensions of the Standard Model, particularly in frameworks that aim to explain the origin of neutrino masses. Their distinct electric charge and clean leptonic signatures make them especially compelling from the standpoint of experimental searches. In this work, we explore the sensitivity of the LHC full run II, including photon-photon fusion, and Future Circular Collider in its hadron-hadron configuration (FCC-hh) to such states, assuming they decay promptly and exclusively into charged leptons either conserving or violating lepton flavor. We find that the FCC-hh, operating at 100 TeV, is uniquely positioned to probe doubly charged scalars with masses up to 7 TeV and possibly establish the mechanism behind neutrino masses
H.E.S.S. detection and multi-wavelength study of the 1 blazar PKS 034627
No full textInternational audiencePKS 0346-27 is a Low Synchrotron Peaked (LSP) blazar at redshift 0.991. The very-high-energy (VHE, E > 100 GeV) spectra of blazars are always affected by absorption by the Extragalactic Background Light (EBL) and subsequently, no blazars have been detected in VHE -rays at redshifts exceeding 1. Extending the redshift range of VHE-detected blazars to will yield insights into the cosmological evolution of both the VHE blazar population and the EBL. This is the goal of a target-of-opportunity (ToO) programme by H.E.S.S. to observe flaring high-redshift () blazars. We report on H.E.S.S. ToO and multi-wavelength observations of the blazar PKS 034627. Along with H.E.S.S., simultaneous data from {\it Fermi}-LAT, {\it Swift} (XRT and UVOT), and ATOM have been analysed and modelled using single-zone leptonic and hadronic models. PKS~0346-27 has been detected by H.E.S.S at a significance of 6.3 during one night, on 3 November 2021, while for other nights before and after this day, upper limits on the VHE flux are determined. No evidence for intra-night -ray variability has been found. A flare in high-energy (HE, ~MeV) -rays detected by {\it Fermi}-LAT preceded the H.E.S.S. detection by 2 days. A fit with a single-zone emission model to the contemporaneous spectral energy distribution during the detection night was possible with a proton-synchrotron-dominated hadronic model, requiring a proton-kinetic-energy-dominated jet power temporarily exceeding the source's Eddington limit, although alternative (e.g. multi-zone) models can not be ruled out. A one-zone leptonic model is, in principle, also able to fit the flare-state SED, however, requiring implausible parameter choices, in particular, extreme Doppler and bulk Lorentz factors of
L’invention de la médecine de la Grèce à la Chine, Paris, Les Belles Lettres, 2026, 358 p.
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Tertiary Lymphoid Structures Are Associated with Enhanced Macrophage Activation and Immune Checkpoint Expression and Predict Outcome in Cervical Cancer
No full textInternational audienceCervical tumors are usually treated using surgery, chemotherapy, and radiotherapy and would benefit from immunotherapies. However, the immune microenvironment in cervical cancer remains poorly described. Tertiary lymphoid structures (TLS) were recently described as markers for better immunotherapy response and overall better prognosis in patients with cancer. We evaluated the cervical tumor immune microenvironment, specifically focusing on TLS, using combined high-throughput phenotyping, soluble factor concentration dosage in the tumor microenvironment, and spatial interaction analyses. We found that TLS presence was associated with a more inflammatory soluble microenvironment, with the presence of B cells as well as more activated macrophages and dendritic cells (DC). Furthermore, this myeloid cell activation was associated with the expression of immune checkpoints, such as PD-L1 and CD40, and the proximity of activated conventional type 2 DCs to CD8+ T cells, indicating better immune interactions and tumor control. Finally, we associated TLS presence, greater B-cell density, and activated DC density with improved progression-free survival, substantiating TLS presence as a potential prognostic marker. Our results provide evidence that TLS presence denotes cell activation and immunotherapy target expression
Culture écrite de l’Antiquité tardive et papyrologie byzantine: [résumé des cours et travaux : 2021-2022]
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Les besoins conflictuels optiques et mécaniques déterminent l'évolution de l'épaisseur de la membrane de l'aile chez les papillons transparents ithomiines
No full textTransparent animals are often thin, which raises the question of their fragility. In clearwing Lepidoptera, the wing thickness is the evolutionary result of conflicting optical and mechanical needs. All else being equal, a thinner membrane lets light better go through, can still sustain the reduced scales it often bears, it has a low stiffness advantageous for flight but it resists less to fatigue and failure, a crucial point. An evolutionary way out of these conflicting needs can be spatial heterogeneity in stiffness, with thicker opaque patches compensating for thinner transparent ones, especially when transparency covers a great wing surface proportion. We tested these predictions in Ithomiine butterflies, a tribe comprising closely-related opaque and transparent unpalatable species. We found that species with partially transparent wings have a thinner membrane in the transparent zone than in the opaque one, which likely helps light getting through and agrees with the lighter weight wings have to support in the transparent zone. Surprisingly, more transparent species have a thicker membrane in their transparent zone. We find no relationship between membrane thickness and scale density, ruling out a predominant role of membrane thickness as a mechanical support for scales. Finally, species with a higher wing proportion occupied by transparency have thicker membranes on their transparent patch, and a greater ratio in thickness between opaque and transparent zones. These latter two results support the hypothesis that clearwing butterflies with larger transparent patches are potentially more fragile and that this frailty is offset by thicker surrounding opaque patches offering higher mechanical resistance, like tubules framing a kite sail. In clearwing butterflies, wing membrane thickness has likely evolved under optical and mechanical selective pressures and further research should experimentally measure the costs, if any, of thinner transparent membranes.Les animaux transparents sont souvent minces, ce qui soulève la question de leur fragilité. Chez les Lépidoptères à ailes transparentes, l’épaisseur de l’aile est le résultat évolutif de besoins optiques et mécaniques contradictoires. Toutes choses égales par ailleurs, une membrane plus fine laisse mieux passer la lumière, et peut pourtant supporter les écailles réduites qu’on trouve souvent dans les zones transparentes. Elle présente une faible rigidité avantageuse pour le vol, mais résiste moins bien mécaniquement à la rupture, un point crucial. Une solution évolutive à ces contraintes opposées peut passer par une hétérogénéité spatiale de la rigidité, avec des zones opaques plus épaisses compensant les zones transparentes plus fines, en particulier lorsque la transparence occupe une grande proportion de la surface alaire.Nous avons testé ces prédictions chez les papillons ithomiines, une tribu comprenant des espèces toxiques étroitement apparentées, à ailes opaques ou transparentes. Nous avons constaté que les espèces partiellement transparentes possèdent une membrane plus fine en zone transparente qu’en zone opaque, ce qui favorise le passage de la lumière et peut quand même soutenir la masse plus faible que les ailes doivent supporter en zone transparente. De manière surprenante, les espèces les plus transparentes présentent une membrane plus épaisse dans leur zone transparente. Nous ne trouvons aucune relation entre l’épaisseur de la membrane et la densité des écailles, ce qui exclut un rôle prédominant de l’épaisseur membranaire comme support mécanique des écailles.Enfin, les espèces dont une plus grande proportion de l’aile est occupée par des zones transparentes présentent des membranes plus épaisses en zone transparente, et un ratio d’épaisseur plus élevé entre les zones opaques et transparentes. Ces deux derniers résultats soutiennent l’hypothèse selon laquelle les papillons à ailes transparentes dotés de larges zones transparentes sont potentiellement plus fragiles, et que cette fragilité est compensée par des zones opaques environnantes plus épaisses, offrant une plus grande résistance mécanique, à la manière de tubulures encadrant la voile d’un cerf-volant. Chez les papillons à ailes transparentes, l’épaisseur de la membrane alaire a probablement évolué sous l’effet de pressions de sélection à la fois optiques et mécaniques, et des recherches futures devraient mesurer expérimentalement les coûts éventuels de membranes transparentes plus fines
Nonconservative Lie series: post-Newtonian binary dynamics at 2.5PN
No full textInternational audienceWe present a fully analytical solution to the dynamics of the non-spinning 2.5 post-Newtonian binary problem, accounting for both the long-term (secular) and short-term (oscillatory) temporal behavior, with no restriction on eccentricity. The radiative degrees of freedom are handled within the nonconservative Hamiltonian framework introduced in a companion paper. In this work, we apply the Lie series method to construct a resonant Birkhoff normal-form and the corresponding generator of the radiation-reaction dynamics. The secular piece reconstructs exactly the Peters-Mathews relations for semi-major axis and eccentricity. The oscillatory piece completes the dynamics and is well suited for gravitational wave templates. The procedure we present in this paper can be systematically employed to cast arbitrary nonconservative systems into extended Hamiltonian form so that the Lie method can be applied
Multiseasonal modeling of pesticide resistance in maize stalk borer
No full textInternational audienceThis study presents a comprehensive approach to modelling the infestation of maize by the maize stalk borer (Busseola fusca) using both chemical control and cultural practices consisting of post-harvest residue management. Two distinct mathematical models are developed: a semi-discrete integro-differential model and a semi-discrete differential model, each addressing different aspects of pest resistance. The integro-differential model captures the dynamics of quantitative resistance, considering resistance as a continuous variable from fully sensitive to fully resistant. The second model, on the other hand, accounts for qualitative resistance by incorporating discrete genetic mutations. Both models consider key factors such as pesticide decay rates, fitness costs associated with resistance, and the impact of integrated pest management (IPM) strategies. Our findings highlight the critical role of fitness costs in delaying resistance development and demonstrate the enhanced effectiveness of IPM techniques over conventional chemical control. This dual-model approach provides a robust framework for designing sustainable pest management practices in agriculture