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Mn(II), Cu(II), and Zn(II) Complexes Based on H 3 nota Derivatives Possessing Picolyl and Picolinate Pendants: Structural and Equilibrium Studies ─ Kinetic Inertness, Electrochemical Properties, and Relaxivity of the Mn Complexes
No full textInternational audienceTwo derivatives of tacn (1,4,7-triazacyclononane) are investigated for their complexation with Cu(II), Zn(II), and Mn(II). The different denticities of macrocyclic ligands Hnoapy and H2noapa offer the possibility to modulate the coordination environment and stability of the complexes. [Cu(noapy)]ClO4(H2O)2 exhibits a square-pyramidal penta-coordinated geometry in the solid state, while UV–visible and EPR spectroscopies and DFT are consistent with a hexa-coordinated species in solutions. The hexa-coordination of zinc(II) in the [Zn(noapy)]ClO4 complex was evidenced in the solid state, thanks to the formation of a 1D coordination polymer through a bridging carboxylate coordinating group. The [Mn2(noapy)2](ClO4)2·H2O complex presents a trigonal prismatic geometry around the cation similar to that of the Zn(II) complex. The stability constants of Hnoapy and H2noapa complexes were measured by pH-potentiometric titrations. The inertness of [Mn(noapa)] and [Mn(noapy)]+ complexes was assessed through Zn(II) exchange reactions, revealing that decomplexation occurs via both spontaneous and proton-assisted pathways. The electrochemical studies in aqueous solutions revealed their resistance toward oxidation at pH 6.7. Relaxivity measurements, supported by DFT calculations, confirmed the presence of one inner-sphere water molecule coordinated to Mn(II) in both [Mn(noapa)] and [Mn(noapy)]+ complexes. Furthermore, 17O NMR studies of water exchange kinetics suggested an associative activation mechanism for [Mn(noapy)]+ and a dissociative activated one for [Mn(noapa)]
MEG-A - The first megaliths builders of the northern Levant” project report on the 2022 archaeological soundings and survey in Menjez (Akkar)
No full textInternational audienc
Pro-inflammatory processes and metabolic syndrome: combined risk of resistance to treatment in patients with schizophrenia from the FACE-SZ cohort
No full textInternational audienceSchizophrenia (SZ) is characterized by a variable clinical expression and course peppered/hampered by severe complications. In particular, resistance to treatment (overall-TRS, treatment resistant SZ including UTRS, ultra-TRS) and metabolic syndrome (MetS) are highly prevalent, and both demonstrated to be underpinned, at least partly, by pro-inflammatory processes. Given that such processes also underlie SZ per se , we hypothesized that potential inter-twinning between SZ-and MetS-related inflammatory processes may exert a combined effect on the risk of having overall-TRS/UTRS. A total of 419 outpatients with SZ underwent clinical assessments and blood sample collection. Using the values of circulating levels of eleven cytokines, we built a ratio between pro-and anti-inflammatory components respectively corresponding to the immunoinflammatory response system (IRS) and the compensatory immunoregulatory reflex system (CIRS) which overall reflect the underlying in-flammatory status. Such ratios allowed to categorize the patients according to Inflammation and MetS on four categories as follow: symbolscript symbolscript symbolscript and Inflam-mation(-)MetS(-). Multivariate logistic regression analysis showed that the combination of inflammation and MetS modulate the risk of having the overall-TRS symbolscript symbolscript 95 %CI [1.04-5.00], p symbolscript 0.039 and symbolscript symbolscript 95 % CI [1.76-11.97], p symbolscript 0.002 overall in comparison to Inflammation(-)MetS(-)]. Moreover, we observed that individuals with UTRS are those associated with both inflammation and/or MetS. Our results demonstrated the potential combined effect of MetS and inflammation towards resistance to treatment. Given that overall-TRS/UTRS are unpredictable while both inflammation and MetS can be early detected and managed, our findings shed new light on the possibility to better prevent treatment resistance in SZ
Extension du prototypage rapide pour les pipelines d’imagerie radioastronomique : Simulation avancée multi-nœud HPC
No full textInternational audienceSimSDP is a rapid prototyping tool designed to provide early estimates of the computation time and power consumption of SKAO’s future SDP processor pipeline. This paper extends a previous proof-of-concept by: (1) exploring more parallelism through dataflow modeling of spectral parallelism, (2) simulating pipeline behavior on multi-core, multi-node CPU architectures, (3) improving performance modeling and incorporating automation of the computation time estimation process. The results show that this tool facilitates the orientation of design decisions by exploring three radio-interferometric imaging algorithms on HPC systems, with an improvement in the reliability of the simulations, the uncertainty being reduced to around 10 %.SimSDP est un outil de prototypage rapide conçu pour fournir des estimations précoces des temps de calcul et de la consommation énergétique du futur pipeline de processeurs SDP de SKAO. Cet article étend une preuve de concept précédente en : (1) explorant davantage de parallélisme grâce à une modélisation en flux de données du parallélisme spectral, (2) simulant le comportement des pipelines sur des architectures multicœurs CPU multi-nœuds, (3) améliorant la modélisation des performances et en intégrant une automatisation du processus d’estimation des temps de calcul. Les résultats montrent que cet outil facilite l’orientation des décisions de conception en explorant trois algorithmes d’imagerie radio-interférométrique sur des systèmes HPC, avec une amélioration de la fiabilité des simulations, l’incertitude étant réduite à environ 10 %
A unified theory of pore-scale chaotic advection
No full textInternational audienceRecent studies reveal the central role of chaotic advection in controlling pore-scale processes including solute mixing and dispersion, chemical reactions, and biological activity. These dynamics have been observed in porous media (PM) with a continuous solid phase (such as porous networks) and PM comprising discrete elements (such as granular matter). However, a unified theory of chaotic advection across these continuous and discrete classes of PM is lacking. Key outstanding questions include: (i) topological unification of discrete and continuous PM; (ii) the impact of the non-smooth geometry of discrete PM; (iii) how exponential stretching arises at contact points in discrete PM; (iv) how fluid folding arises in continuous PM; (v) the impact of discontinuous mixing in continuous PM; and (vi) generalised models for the Lyapunov exponent in both PM classes. We address these questions via a unified theory of pore-scale chaotic advection. We show that fluid stretching and folding (SF) in discrete and continuous PM arise via the topological complexity of the medium. Mixing in continuous PM manifests as discontinuous mixing through a combination of SF and cutting and shuffling (CS) actions, but the rate of mixing is governed by SF only. Conversely, discrete PM involves SF motions only. These mechanisms are unified by showing that continuous PM is analogous to discrete PM with smooth, finite contacts. This unified theory provides insights into the pore-scale chaotic advection across a broad class of porous materials and points to design of novel porous architectures with tuneable mixing and transport properties
A different genealogy for twentieth-century ecological thought: Max Sorre’s human ecology
No full textInternational audienceThe French geographer Max Sorre (1880–1962) developed a brand of human ecology from the 1920s onwards. Discernibly distinct from the human ecology developed by sociologists in Chicago, Sorre's human ecology deepens humankind's relations to the physical and living environment (including through medical geography). This cognitive horizon manifested itself in extensive and distinctive research on life, disease, climate and diets. Through such an ecological understanding of humankind, the aim was to return to a geographical question: understanding the durable conditions for the habitability of the globe, and explaining the inhabited earth. In addition to analysing these issues, this text also seeks to delimit the various procedures by which Sorre and the biological and medical sciences reciprocally imported one another's ideas. Indeed, Sorre showed himself to be particularly open to other disciplines, corresponding with climatologists, zoologists and physicians. In return, the latter also adopted certain proposals formulated by the geographer, notably his concept of the ‘pathogenic complex’. Finally, the text will try to objectify the constituent conceptions of this ecological knowledge, considering it as the rendering of material relations to the environment, but also as the result of certain scholarly representations
Luby's MIS Algorithms Made Self-Stabilizing
No full textInternational audienceWe reconsider two well-known distributed randomized algorithms computing a maximal independent set, proposed in the seminal work of Luby (1986). We enhance these algorithms such that they become self-stabilizing without sacrificing their run-time, i.e., both stabilize in O(log n) synchronous rounds w.h.p. on any n-node graph. The first algorithm gets along with three states, but needs to know an upper bound on the maximum degree. The second does not need any information about the graph, but uses a number of states that is linear in the node degree. Both algorithms use messages of logarithmic size
Transitions de phase photoinduites ultrarapides dans des matériaux à changement de phase de type ferroélectriques sans plomb
No full textsupervisors Niels Keller and Roman Bertoni (department of materials and light)sous la direction de Niels Keller et de Roman Bertoni dans le département Matériaux et Lumièr
Helical‐like scan and upright CBCT imaging algorithms based on robotic‐arm system
No full textInternational audienceBackground: Upright position CT scans enable body imaging under realistic conditions and have been widely adopted in rehabilitation medicine. However, they face challenges such as limited acquisition angles, floor stability issues, and a restricted field of view (FoV) along the Z-axis.Purpose: The objective of this study is to propose an algorithm that enables high-quality image reconstruction in lightweight robotic-arm cone-beam CT (CBCT) systems, addressing challenges related to mechanical vibrations, a limited Z-axis scanning range, and inhomogeneous sampling.Methods: A long Z-axis helical steel ball phantom and a greedy ball-positioning algorithm are proposed to enhance geometrical calibration accuracy. A data completeness-driven method optimizes the scanning pitch for rapid full-body scans without significant image degradation. Additionally, a normalized projection-based FDK-style algorithm enhances reconstruction quality under reverse helical scanning constraints.Results: The proposed upright reverse helical CBCT system demonstrated competitive reconstruction accuracy, achieving RMSE values of 0.0421 for Shepp-Logan, 0.3163 for foam-like, and 115.08 for VHP phantoms. Additionally, the proposed algorithm maintained computational efficiency, completing reconstructions in 45.3, 64.0, and 189.4 s, respectively, significantly outperforming iterative methods while preserving image quality. Furthermore, it significantly reduced radiation dose compared to conventional helical CT, achieving dose reductions from 460 to 50.7 mGy.cm for a 32 cm phantom and from 1050.0 to 112.6 mGy cm for a 16 cm water phantom.Conclusions: This work provides a robust solution for long-length Z-axis imaging in upright positions, as well as for unstable and nonstandard projection sampling. The proposed framework holds potential for advancing the use of robotic-arm upright CBCT systems in orthopedic functional evaluations and other clinical applications
