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Signal Processing and Machine Learning Algorithms for Precise Timing with PICOSEC Micromegas Detectors
No full textInternational audienceHigh particle rates in current and future experiments make pile-up phenomena a critical issue for extracting useful information. In this context, timing can be important as the 4 dimension parameter for triggering or event reconstruction. The PICOSEC-Micromegas detector has been shown to offer precise timing of the order of tens of ps. In this work, novel signal processing algorithms are being developed and evaluated to demonstrate the technology's ability for online precise timing. We propose, an algorithm based on Artificial Neural Networks (ANN). This algorithm uses a model to train the ANN. The performance of the different algorithms is evaluated using experimental data, resulting in a timing resolution of 18.3 0.6 ps, comparable to the standard analysis based on the Constant Fraction Discrimination technique. Additionally, an alternative algorithm using the charge of the pulse exceeding a threshold as a parameter to correct for systematic effects is reported
Exploring traditional Japanese herbal ointments for wound healing: A wide diversity of practices, metabolites, and effects
No full textInternational audienceEthnopharmacological relevance: In Kampo Japanese traditional medicine, ointments are used to treat skin wounds and promote wound healing. These ointments are prepared by extracting herbal crude drugs in sesame oil, a technique that has been practised for centuries. Their preparation varies significantly in terms of ingredients, plant species, temperature, and extraction time, leading to a wide diversity of formulations. Unlike hydrophilic plant extracts, the phytochemical composition and wound-healing efficacy of sesame oil-based herbal extractions remain largely unexplored.Objective: The objective of this study is to address this gap by focusing on lipophilic plant metabolites present in these topical formulations and to explore their potential contribution to wound healing using a keratinocyte model in vitro.Materials and methods: A survey was conducted to document Kampo ointment-related practices, focusing on highlighting variations in extraction protocols, crude drug origins, and manufacturing practices. Sample preparation excluded solid compounds from the formulations and used different solvents for the metabolomic and biological aspects. Metabolomics profiling was performed using LC-HRMS and LC-HRMS/MS to analyse the impact of different preparation temperatures and botanical sources on extract composition. In vitro assays assessed keratinocyte migration and proliferation using scratch assays and EdU (5-ethynyl-2′-deoxyuridine) incorporation and data were evaluated with appropriate statistical methods.Results: A diversity of practices concerning the Kampo ointments Shiunkō, and Shinsen taitsukō was identified. This mainly concerned the extraction temperature with three protocols: maceration (M), Low Heating (LH) and High Heating (HH). Significant differences in metabolite profiles were observed, particularly with regard to the heating temperature of the sesame oil and the origin of the crude drugs. These parameters markedly influenced the chemical composition through both the formation of transformed lipids and the degradation of bioactive compounds such as tocopherols and sterols. While the variety of sesame oils and Angelica acutiloba extracts showed no distinct biological effects on keratinocyte migration, the complete formulas Shiunkō and Shinsen taitsukō unexpectedly delayed wound closure in the model. This result is possibly due to the degradation of wound-healing metabolites and the presence of cytotoxic ones, or the inadequacy of the cell model used to evaluate these complex lipophilic preparations.Conclusion: This study highlights the diversity and complexity of traditional Kampo ointments in terms of chemical composition and, to a lesser extent, biological activity. Preparation temperature and ingredient origin
Radiobiology Contributions and Perspectives in Hadron Therapy, with a focus on carbon ions: Report from the workshop Hadron therapy for life, Caen, March 2025
No full textISTCTInternational audienceThe "Hadrontherapy for Life" symposium in Caen, France highlighted that a new era of radiobiology is fundamental for advancing particle therapy to the next level. A radiobiology capable of integrating molecular biology and omics technologies is needed to deeply analyze treatment responses and underlying mechanisms.Key challenges discussed at the symposium included tumor hypoxia, which remains only partially mitigated by high-LET radiation, and the specificity of carbon ions, or more broadly, high LET particles, considered as "new drugs" capable of providing systemic benefits beyond local tumor control, including their potential to promote immunogenicity. Moreover, emerging modalities, such as Ultra High Dose Rate irradiation, and spatial fractionated beam were also discussed, with consensus that all require dedicated and coordinated radiobiological investigations.Infrastructure presentations highlighted the international capabilities of leading centers in Europe and Asia, emphasizing the importance of integrating radiobiology into clinical programs, advancing multi-ion experimentation, and adopting innovative experimental models, such as organoids and/or 3D cell cultures. Participants also stressed the need for greater access to animal experimentation facilities, which are essential for accelerating progress in the field. Furthermore, the meeting underscored translational endpoints such as biomarker development, a hot topic in current radiotherapy. The C400 accelerator enables Caen to incorporate radiobiology from its very inception, establishing a European hub for collaborative research. Round-table discussions emphasized the importance of harmonized protocols, dedicated in vivo irradiation rooms, international training programs with exchange of students and researchers, and comprehensive patient biobanking.In summary, the symposium reinforced the essential role of radiobiology in advancing hadrontherapy (HT), providing strategic directions for translational research, infrastructure development, and international collaborations to accelerate personalized and effective particle therapy
Crystallization behavior of co-polyesters based on hydroxy fatty acids extracted from tomato peel agro-wastes
No full textInternational audienceThis work investigates the crystallization behavior of bio-based slightly crosslinked polyester networks synthesized from long-chain hydroxy fatty acids. The crystallization kinetics and the melting behavior were assessed using a combination of modulated-temperature differential scanning calorimetry (MT-DSC) and fast scanning calorimetry (FSC). The characterization of the crystalline phases was performed by X-ray diffraction (XRD) and polarized-light optical (POM) microscopy. A methodology based on calorimetric investigations was used, allowing to estimate the theoretical value of the melting enthalpy of the initial cutin monomers as well as of the derived co-polyester networks. The results obtained by this method allowed to estimate the crystalline content . The combination of XRD and calorimetric analyses evidenced the existence of polymorphs with different stabilities over time at room temperature, characterized by a monotropic transition from the metastable crystal phase (α-phase) to more stable crystal phases (β'and β-phases) depending on the crystallization time accorded to the monomers and the crosslinked co-polyesters. This work delves deeper into the complex crystallization behavior of biobased polyesters, which could eventually allow a better control over the properties of these materials
Field-induced states and thermodynamics of the frustrated Heisenberg antiferromagnet on a square lattice
No full textWe investigate the ground-state and finite-temperature properties of the - Heisenberg antiferromagnet on the square lattice in the presence of an external magnetic field. We focus on the highly frustrated regime around . The - phase diagram is investigated with particular emphasis on the finite-temperature transition into the "up-up-up-down" state that is stabilized by thermal and quantum fluctuations and manifests itself as a plateau at one half of the saturation magnetization in the quantum case. We also discuss the enhanced magnetocaloric effect associated to the ground-state degeneracy that arises at the saturation field for . For reference, we first study the classical case by classical Monte Carlo simulations. Then we turn to the extreme quantum limit of spin-1/2 where we perform zero- and finite-temperature Lanczos calculations
A gradient descent method for inverse learning of a sintering model with specific physical parameter denormalization
No full textInternational audienceAssessment of the physical sintering parameter from dilatometry curves can be an arch and time-consuming task. A hybrid method is proposed, coupling an inverse problem approach applied to the physics of sintering and the machine learning methodology to identify the parameters by convergence. The identification approach is based on the gradient descent optimization to identify simultaneously all the parameters, dataset learning/testing split to mitigate the experimental noise and the dataset normalization for an efficient gradient descent learning process. A challenging physical parameters denormalization has been developed for the sintering case. The resulting approach can be applied to experimental data like Master Sintering Curve (MSC) dilatometry, a very common approach in the literature. This inverse learning approach has similar architecture than artificial neurons. These smart physical neurons are very efficient as only two succeed in modeling complex sintering problems, a promising prospect for machine learning approaches
Gyrotropy-induced symmetry breaking in RF-specific plasma wall interaction: Mechanisms and mitigation strategies
No full textInternational audienceIon cyclotron range of frequencies (ICRF) heating is essential for creating plasma in next-generation fusion devices. ICRF antennas often produce localized wall erosion, reducing reliability, material survivability, and overall plasma performance. We show that the wave physics' gyrotropy is among the causes of toroidal and poloidal asymmetries in these erosion spots, and that this source of asymmetry can be compensated for either by controlling the poloidal phasing or by modifying the limiter shapes
Stepwise recombination suppression around the mating-type locus associated with a diploid-like life cycle in Schizothecium fungi
No full textInternational audienceRecombination suppression often evolves around sex-determining loci and extends stepwise, resulting in adjacent regions with different levels of divergence between sex chromosomes, called evolutionary strata. In Ascomycota fungi, evolutionary strata around the mating-type (MAT) locus have been reported only in pseudo-homothallic species, which have a diploid-like life cycle with mycelia carrying nuclei of both mating types. In contrast, no recombination suppression has been observed in heterothallic fungi, where colonies contain only a single mating type. Here, we investigated the evolution of recombination suppression in a clade of dung fungi encompassing 16 pseudo-homothallic and three heterothallic sibling species from the Schizothecium genus (Ascomycota, Sordariales). The analysis of genetic divergence based on genome sequencing indicated recombination suppression around the MAT locus in all 13 pseudo-homothallic species examined. The nonrecombining region ranged from 600 kb to 1.6 Mb and harbored multiple evolutionary strata, varying in size and number among species. The clustering of alleles according to mating type in gene genealogies, the high linkage disequilibrium, and an inversion in one species supported the lack of recombination in the MAT-proximal region in pseudo-homothallic species. The overall lack of trans-specific polymorphism suggested multiple independent recombination suppression events or occasional recombination/genic conversion. In heterothallic species, progeny analyses showed that recombination occurs in regions at physical distances from the MAT locus similar to those in which it is lacking in the pseudo-homothallic species. We thus revealed here multiple, likely independent evolutionary strata, associated with an extended diploid-like stage in Schizothecium fungi
Study of SIDIS Unpolarized Cross Sections from a He Target with the Solenoidal Large Intensity Device at JLab
No full textInternational audienceIn this paper we present a detailed impact study of semi-inclusive deep inelastic scattering unpolarized cross sections' measurements using the proposed SoLID apparatus at Jefferson Lab. This type of data, collected at large Bjorken , moderate values of and small values of the transverse momentum of produced hadrons, , allows to study transverse momentum dependent (TMD) parton distribution and fragmentation functions in a still poorly explored region. We present the projected results for charged light mesons based on simulated data. For the azimuthal-angle integrated cross sections we adopt the TMD framework up to the next-to-next-to-next-to-leading-logarithmic (N3LL) accuracy, while a simpler TMD parton model is employed for the study of azimuthal angular dependencies
From closed shells to open shells: Coupled-cluster calculations of atomic nuclei
No full textInternational audienceCoupled-cluster theory is a powerful tool for first-principles calculations of atomic nuclei, enabling accurate predictions of nuclear observables across the Segrè chart. While coupled-cluster computations are especially efficient at shell closures, extensions have been developed to tackle open-shell nuclei, by exploiting the equation-of-motion method or by expanding the coupled-cluster wave function on top of a symmetry-breaking (either deformed or superfluid) reference state. In this study, we provide a comprehensive comparison of these different formulations applied to the calcium and nickel isotopes using nuclear two- and three-body interactions from chiral effective field theory. Based on ground-state energies, two-neutron separation energies, and two-neutron shell gaps, different coupled-cluster computations - based on symmetry-broken reference states and equation-of-motion techniques - offer consistent descriptions of bulk properties across medium-mass isotopic chains