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On the location and the strength of controllers to desynchronize coupled Kuramoto oscillators
Get PDFSynchronization is an ubiquitous phenomenon in systems composed of coupled oscillators. While it is often beneficial to the system under consideration, there are nevertheless relevant examples where one would like to reduce it, e.g., in brain dynamics. Indeed although synchronization is essential to the good functioning of brain dynamics, hyper-synchronization can induce problems such as epilepsy seizures. Motivated by this problem, we study a pinning control scheme able to decrease synchronization in a system of coupled Kuramoto oscillators, by focusing on the determination of the best selection strategy for the controllers, i.e., capable to guarantee a lower synchronization level. We show that hubs are generally the most advantageous nodes to control, especially when the degree distribution is heterogeneous. Nevertheless in cases of homogeneous degree distribution having a large distance between pinned nodes, in term of network shortest path length, appears to be also a key factor. We challenge the analytical findings on both synthetic and empirical networks, e.g., brain connectome. Our results are in line with previous works that studied pinning control with the opposite goal, i.e. increasing synchronization. These observations shed light on an interesting universality of good practice of node selection disregarding the actual goal of the control scheme
Strategy to control synchronized dynamics in swarmalator systems
Get PDFSynchronization forms the basis of many coordination phenomena in natural systems, enabling them to function cohesively and support their fundamental operations. However, there are scenarios where synchronization disrupts a system's proper functioning, necessitating mechanisms to control or suppress it. While several methods exist for controlling synchronization in nonspatially embedded oscillators, to the best of our knowledge, no such strategies have been developed for swarmalators (oscillators that simultaneously move in space and synchronize in time). In this work, we address this gap by introducing a control strategy based on Hamiltonian control theory to suppress synchronization in a system of swarmalators confined to a one-dimensional space. The numerical investigations we performed demonstrate that the proposed control strategy effectively suppresses synchronized dynamics within the swarmalator population. We studied the impact of the number of controlled swarmalators and the strength of the control term in its original form and a simplified one
Les ducs de Bourgogne et l'administration du duché (1272-1349):Une histoire documentaire de la principauté capétienne de Bourgogne
No full textLe duché capétien de Bourgogne est resté dans l’ombre des ducs Valois. La période qui court du principat de Robert II (1272-1306) à celui d’Eudes IV (1315-1349) coïncide pourtant avec une expansion territoriale sans précédent, un accroissement de l’activité administrative et une affirmation du pouvoir princier. À partir d’un riche dossier documentaire, ce livre restitue le fonctionnement de l’administration ducale au tournant des XIIIe et XIVe siècles. En mêlant approches paléographiques et diplomatiques, les gestes, les travaux et les carrières des agents ducaux sont scrutés afin d’établir une histoire documentaire de la principauté capétienne de Bourgogne.Trois temps principaux, qui répondent aux carrières des administrateurs et à la vie politique du duché, sont étudiés. Le premier correspond à la carrière d’un clerc nommé maître Raoul († 1289), principal administrateur du duc Robert II, dont les très nombreux écrits donnent des perspectives inédites sur les rouages de l’administration dans la seconde moitié du XIIIe siècle. Le deuxième, dédié aux trois premières décennies du XIVe siècle, met en évidence la manière dont la construction administrative du duché a d’abord été une réponse aux épreuves du temps. Pour faire face aux crises agraires des années 1310-1320 et endiguer un endettement galopant, les ducs et leurs agents ont établi des cadres administratifs nouveaux, notamment la Chambre des comptes de Dijon. La troisième et dernière partie interroge la manière dont le duc Eudes IV a gouverné le duché après l’acquisition des comtés de Bourgogne et d’Artois en 1330. Pour administrer ce vaste espace bourguignon, le pouvoir ducal s’est enraciné dans la ville de Dijon, alors érigée au rang de capitale administrative et financière.À travers cette étude, ce sont les ressorts qui président à l’établissement d’une administration princière dans la seconde moitié du XIIIe siècle et les premières décennies du XIVe siècle qui sont mis en lumière
Démêler les racines du récent tournant politique en Colombie:De Uribe à Petro
Get PDFLa trajectoire politique de la Colombie, historiquement caractérisée par un virage persistant vers la droite, a subi une transformation sismique. Précédant la pandémie de COVID-19, une vague de mécontentement collectif a balayé la nation. Cette force, née du mécontentement du peuple, cherchait à perturber l’influence durable d’un cycle ultraconservateur bien établi, avec Álvaro Uribe Vélez comme figure centrale. Le changement qui en a résulté a marqué l’avènement d’un nouveau paradigme politique, dirigé par Gustavo Petro. Dans cet article, j’entreprends une exploration, plongeant dans les racines historiques et les processus sous-jacents qui expliquent de manière critique le tournant politique récent de la Colombie
Software complementary to paper "Buy as you need: Nutrition and food storage imperfections "
No full textSotfware supporting paper "Buy as you need: Nutrition and food storage imperfections
Complete set of broadening coefficients and high-order line-shape parameters for N<sub>2</sub>-broadened CO<sub>2</sub> lines, for temperatures ranging from 100 K to 1000 K
No full textBroadening coefficients and high-order line-shape parameters, including the speed dependence of the line width, Dicke narrowing and first-order line-mixing parameters, are predicted for N 2-broadened CO 2 lines over a temperature range from 100 K to 1000 K using requantized molecular dynamics simulations (rCMDS). By employing an intermolecular potential, classical equations of motion, and a requantization procedure, rCMDS enable the calculations of N 2-broadened CO 2 spectra across a wide temperature range without use of any adjustable parameters. For each considered temperature, line-shape parameters were retrieved from fits of the rCMDS spectra using the Voigt, speed-dependent Voigt, and Hartmann-Tran profiles, with first-order line mixing accounted for. The obtained parameters and their temperature dependences were compared with experimental data at various temperatures showing excellent agreements. We demonstrate that parameters and their temperature dependences obtained at Earth's atmospheric temperatures cannot be used to deduce with accuracy those at higher temperatures, relevant for studies of exoplanetary atmospheres and combustion media. Comparisons with databases show that several parameters and their temperature dependences need to be updated by incorporating accurate high-temperature data to correctly simulate the absorption spectra of N 2-broadened CO 2 from low to high temperatures.</p
The “HARMONIC-Radiotherapy” registry:assessing late outcomes of advanced radiotherapy in children, adolescents and young adults
No full textObjective: The “HARMONIC-Radiotherapy” study aims to evaluate late outcomes of contemporary techniques of external beam radiotherapy (EBRT) in children, adolescents, and young adults. Methods: HARMONIC-RT (NCT04746729) is a registry complemented by a biobank and substudies exploring patient subsets undergoing interventional procedures. The registry includes patients treated with EBRT for a first neoplasm from 2000 onwards before the age of 22 years and is currently active in five centres in Belgium, Denmark, France, and Germany. The registry study is open to enrolling patients retrospectively or prospectively for ten years (2021–2031) and collecting follow-up information for 10–20 years (2021–2041). The collected data includes demographics, socioeconomics, general health information, risk factors, routine biological tests, treatments (radiation, surgeries, and systemic therapy), cancer events, and relevant chronic or fatal health conditions. DICOM-RT files are centrally stored and evaluated allowing whole-body dosimetry calculation from therapeutic and diagnostic exposures. The substudies investigate early-/intermediate-term endpoints measured on MRIs or blood/saliva samples (for endocrine and vascular toxicities, carcinogenesis), and parent-/patient-reported outcomes. Linkage with population-based cancer registries and public health insurance databases is planned for long-term follow-up. Results: By November 2024, 2,300 patients were included. The first primary cancers were mainly medulloblastomas (20%), soft tissue sarcomas (12%), ependymomas (12%), and neuroblastomas (9%). Genetic cancer predisposition was reported for 7% of patients. First EBRT was mainly received before 2020 (62% of patients), before the age of 12 years (65%), and after – or concomitantly with – chemotherapy (61%). First EBRT used protons (68%), photons (30%), or both (2%). Most treatments involved intensity-modulated techniques (photons: 55%, protons: 84% of irradiation fields). Questionnaires assessing quality of life, fatigue and education were completed by 210 patients. Biological samples were collected from 42 patients before and after EBRT. Conclusion: HARMONIC-RT is the first multi-centric registry of paediatric patients treated with contemporary EBRT techniques in Europe. While enrolment and follow-up are continuing in the participating centres, we aim to open the registry to other centres. We projected that 10,000 patients could be included by 2031 in a large European study – enabling the evaluation of late outcomes such as second cancers. Adhering to FAIR principles, HARMONIC-RT aims to support future international studies, and it has been made compatible with the U.S. Paediatric Proton/Photon Consortium Registry. The registry’s structure and associated documentation are freely available for research purposes.<br/
A chimeric Mla-Pqi lipid transport system is required for Brucella abortus survival in macrophages
No full textThe cell envelope of gram-negative bacteria is composed of an inner and an outer membrane. In Escherichia coli, several pathways mediate phospholipid transport between the two membranes, including the Mla (i.e., maintenance of lipid asymmetry) and Pqi (i.e., paraquat inducible) systems. Here, we identify and characterise in the intracellular pathogen Brucella abortus a complex named Mpc, which exhibits homology to both Mla and Pqi components. Mpc is required for bacterial growth under envelope stress conditions, and for survival within macrophages during the early stages of infection. Analyses of protein-protein interactions and structural predictions suggest that the Mpc complex bridges the two membranes of the bacterial cell envelope. Absence of this system results in altered lipid composition of the outer membrane vesicles, indicating that Mpc plays a role in lipid transport between the membranes. Our sequence comparisons reveal that Mpc is conserved across numerous species of Hyphomicrobiales. The discovery of this novel lipid-trafficking system expands our understanding of the diversity and evolution of lipid-transport mechanisms in diderm bacteria.</p