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Search for Magnetic Monopoles with the Complete ANTARES Dataset
No full textInternational audienceThis study presents a novel search for magnetic monopoles using data collected over a 14 year period (2008-2022) by the ANTARES neutrino telescope. The interaction of magnetic monopoles with matter was modeled according to Kazama, Yang, and Goldhaber cross-section. Upper limits on the flux of magnetic monopoles are obtained for velocities both above and below the Cherenkov threshold. No events consistent with the passage of magnetic monopoles were detected, enabling the setting of an upper flux limit for relativistic magnetic monopoles of the order of
Cyanide cubic cages: soluble molecular counterparts of prussian blue analogues
No full textInternational audienceHerein, we present a comprehensive review focusing on cyanide-bridged cubic complexes that have emerged over the last years as soluble molecular models of the well-known three-dimensional Prussian Blue Analogues (PBAs). We first describe the synthetic strategies and highlight the peculiarities of molecular cubes in comparison to the inorganic polymeric PBAs. Then, we review solution studies carried out with these soluble counterparts of PBAs, considering in particular supramolecular aspects. We also summarize efforts to transfer the original properties of PBAs to cubic complexes by highlighting both their similarities and specificities. Furthermore, outstanding electronic properties such as the access of multiple electronic states resulting in multiple bands electrochromism, or the stimuli-induced switching of electronic states associated with a change in physical properties are surveyed. Finally, recent attempts at surface deposition of functional molecular cubes or their integration into devices are presented
Predicting climate impacts on health at subseasonal-to-seasonal timescales.
No full textInternational audienceThe potential to use subseasonal-to-seasonal (S2S) prediction systems for outcomes in health is presented, using four case studies of malaria, dengue, heat waves, and meningococcal meningitis. While promising, many such applications are currently in the demonstration phase, and examples of operationalizing S2S-based early warning systems, fully integrated with decision support, have yet to emerge. Potential reasons for this operationalization bottleneck are discussed, which include restrictions on open access to health and climate data, the unfulfilled requirement for training in the use of such systems, and the mismatch between the prediction paradigm and the decision entry points in health-planning systems. The S2S project, sponsored by the World Meteorological Organization, may help to demonstrate the potential application of climate information, but the lack of real-time access inhibits the operationalization of evaluated systems. It is recommended that partnership platforms, established through the Global Framework for Climate Services and related mechanisms, enable the climate and health academic and operational communities to work together on real-time provision and assessment of health early warning systems. This is particularly important in developing countries where climate-driven health outcomes can be severe
Coexistence of Photosynthetic Marine Microorganisms, Viruses, and Grazers: Toward Integration in Ocean Ecosystem Models
No full textInternational audiencePhotosynthetic microorganisms are responsible for primary production at the base of the marine food web that impacts ocean biogeochemistry and ecological interactions. The growth of these microorganisms is balanced by mortality processes, including top-down losses from zooplankton grazing and infection and lysis by viruses. Multiple types of grazers and viruses often coexist despite apparent competition for the same (or similar) microorganisms. Here, we develop a community model of photosynthetic microorganisms, grazers, and viruses that accounts for molar cell and virion elemental quotas suitable for incorporation into ocean ecosystem models. Our aim is to investigate mechanisms that enable coexistence of a virus and a grazer with a single phytoplankton type. To do so, we evaluate the extent to which coexistence is facilitated by: (i) infected phytoplankton, potentially subject to non-preferential intraguild predation, where grazers feed on virally infected microorganisms; (ii) heterogeneity in susceptibility to infection, where microorganisms vary in their resistance to the virus either intracellularly or extracellularly; and (iii) the inclusion of higher-order mortality terms for the predators. We find evidence for a trade-off between the virus latent period and virulence in facilitating a coexistence regime. The inclusion of an explicit latent period can generate oscillations of all populations that facilitate coexistence by reducing the growth rate of the free virus, or lead to system collapse when oscillations become too large. Heterogeneity in phage susceptibility promotes coexistence through resource partitioning between the predators, while higher-order mortality terms widen the coexistence regime by stabilizing the system. We observe strong sensitivity of model outcomes to viral life history traits, including shifts in infected cell percentages and the balance between virally and zooplankton-induced mortality. Finally, taking advantage of algebraic calculation of model equilibria, we identify life history trait parameter combinations that yield realistic ecological properties in simplified oligotrophic and mesotrophic epipelagic environments. Importantly, our ecological models suggest that ongoing efforts to embed virus dynamics in large-scale ocean ecosystem models should likely include phytoplankton types that are moderately to strongly resistant to viral infection and lysis
Theodor Lipps 1851-1914
No full textInternational audienceSynthèse en anglais présentant la psychologie phénoménologique de Theodor Lipps
Evaluation of the uncertainty in calculating nanodosimetric quantities due to the use of different interaction cross sections in Monte Carlo track structure codes
No full textInternational audienceThis study evaluates the uncertainty in nanodosimetric calculations caused by variations in interaction cross sections within Monte Carlo Track Structure (MCTS) simulation codes. Nanodosimetry relies on accurately simulating particle interactions at the molecular scale. Different MCTS codes employ distinct physical models and datasets for electron interactions in liquid water, a surrogate for biological tissues. The paper focuses on the Ionization Cluster Size Distribution (ICSD) generated by electrons of varying energies in nanometric volumes. Seven MCTS codes were tested using their native cross sections and a common dataset derived from averaging data used in the participating codes. The results reveal significant discrepancies among the codes in ICSDs and derived biologically relevant nanodosimetric quantities such as mean ionization numbers (M1) and probabilities of obtaining two or more ionizations (F2). The largest variations were observed for low-energy electrons, where the contribution from interaction cross sections dominates the overall uncertainties. For instance, M1 values for ICSDs of electron of 20 eV can differ by around 45 % (RSD) and 34 % (RSD) was found for F2 values of ICSDs of electrons of 50 eV. Using common cross sections substantially reduced the discrepancies, suggesting that cross section datasets are the primary source of variability. Finally, estimates of deoxyribonucleic acid (DNA) damage using the PARTRAC code highlight tht cross section variations have a non-negligible impact simulated biological outcomes, particularly for double-strand breaks (DSBs) Indeed, despite the fact that many other parameters in the simulation that can greatly differ from one code to another, the different interaction cross-sections studied in this work can lead to differences in the number of DSBs calculated with the PARTRAC code of up to 15%
Beyond uniqueness: Relaxation calculus of junction conditions for coercive Hamilton-Jacobi equations
No full textInternational audienceA junction is a particular network given by the collection of half lines glued together at the origin. On such a junction, we consider evolutive Hamilton-Jacobi equations with coercive Hamiltonians. Furthermore,we consider a general desired junction condition at the origin, given by some monotone function .There is existence and uniqueness of solutions which only satisfy weakly the junction condition (at the origin, they satisfy either the desired junction condition or the PDE).We show that those solutions satisfy strongly a relaxed junction condition (that we can recognize as an effective junction condition). It is remarkable that this relaxed condition can be computed in three different but equivalent ways: 1) using viscosity inequalities, 2) using Godunov fluxes, 3) using Riemann problems.Our result goes beyond uniqueness theory, in the following sense: solutions to two different desired junction conditions and do coincide if
Paying for Training to Make Training Pay Off: EvidenceFrom France
No full textInternational audienceThis paper investigates the impact of increased financial compensation during training on jobseekers' labor market outcomes. We exploit a reform implemented in France in May 2021 that raised training allowances exclusively for non- recipients of unemployment benefits. Using administrative longitudinal data, we compare the trajectories of trainees affected and unaffected by the reform. Our empirical strategy combines a synthetic triple- difference estimator with an event- study framework. We find no evidence that the reform increased employment rates within 24 months of training entry, but it did enhance job quality, improving both stability and alignment with the training field
LHAASO observation of Mrk 421 during 2021 March - 2024 March: a comprehensive VHE catalog of multi-timescale outbursts and its time average behavior
No full textInternational audienceThe Large High Altitude Air Shower Observatory (LHAASO) monitors sources within its field of view for up to 7 hours daily, achieving a duty cycle exceeding 98% and an annual point-source sensitivity of 1.5% Crab Units (CU) in the very high energy (VHE) band. This unbiased sky-survey mode facilitates systematic monitoring and investigation of outburst phenomena. In this paper, we present results from an unprecedented three-year monitoring campaign (March 2021--March 2024) of Mrk421 using LHAASO, spanning energies from 0.4 TeV to 20 TeV. We find that the blazar stayed in a quiescent state in 2021 and became active starting in 2022 with a total of 23 VHE outburst events identified, where the highest observed daily significance reaches with a flux equivalent to approximately 3.3~CU. LHAASO's continuous monitoring suggests the flaring occupancy of Mrk~421 to be around 14%. During long-term monitoring, multiwavelength (MWL) variability and correlation analyses are conducted using complementary data from Fermi-LAT, MAXI-GSC, Swift-XRT, and ZTF. A significant correlation () is observed between X-ray and VHE bands with no detectable time lag, while the correlation between GeV and TeV bands is weaker. The flux distribution of the TeV emission during the quiescent state is different from that in the active state, implying the existence of two modes of energy dissipation in the blazar jet. Using simultaneous MWL data, we also analyzed both the long-term and outburst-period SEDs, and discussed the possible origin of the outburst events
Nonnegativity certificates for finite semi-algebraic sets
No full textWe introduce new certificates for nonnegativity of multivariate polynomials with rational coefficients over zero-dimensional semi-algebraic sets. They are perfectly complete, certifying every nonnegative polynomial, and perfectly sound, correctly identifying negativity. We rely on resultants computations and Rational Univariate Representations (RUR) and make no assumptions on the input.For the univariate case, we introduce a perturbation technique that avoids root approximation and does not alter the (bit)size of the input. For multivariate polynomials, we make a reduction to the univariate case using RUR.For the dense case, we compute a certificate in OB(d 4n+3 (d + τ )) bit operations; it involves numbers of bitsize O(d 3n+2 (d + τ )), where n is the number of variables, d the degree, and τ the maximum coefficient bitsize of the polynomials. For the sparse case, we provide the first sparse certificate based on the Newton polytope Q of the input polynomials. We compute in OB(vol(Q) 8 (n!) 8 2 5n+3 (n + τ )),For semi-algebraic sets with s inequalities, we present two approaches. The first performs a reduction to the algebraic case and has complexity OB(2 (3ω+3)s d 5n τ ); it is purely algebraic approach and does not require root approximation. The second exploits approximate Lagrange interpolation and matches the O(sd 4n τ ) bitsize bounds of recent work by Baldi, Krick, and Mourrain [2] while improving complexity by orders of magnitude and removing all structural assumptions on the input.Additionally, we provide a witness of negativity, ensuring that we either obtain a certificate or it does not exist.</div