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Green gold of the Pacific: unlocking compounds from terrestrial flora for antitumor and immunomodulatory drug discovery
No full textInternational audienceCovering up to 2025Natural products (NPs) from the terrestrial biodiversity play a key role in oncology drug discovery. While historically identified through bioactivity-guided fractionation, recent advances in high-content screening (HCS) assays, metabolomics, and in silico modeling have significantly enhanced the potential and attractiveness of flora-derived NPs for the development of anticancer therapeutics. This includes immunomodulatory molecules that are able to target the tumor microenvironment to promote immune-mediated clearance of the tumor, thereby improving patient response. This review highlights the untapped potential of molecules extracted from the South Pacific's terrestrial flora in the search for novel antitumor and immunomodulatory compounds. The unique biodiversity of Oceania, including Australia, New Zealand, and Pacific Island Countries and Territories (PICTs) across Micronesia, Melanesia and Polynesia, offers a promising yet largely unexplored reservoir for discovering plant-derived molecules with antitumor and immunomodulatory activities. Herein, we examine the recent pharmacological advances in this field and highlight the need for sustainable and collaborative research. Leveraging cutting-edge technologies could help overcome the challenge of NP-based drug discovery on these geographically isolated islands, unlocking the region's vast potential for plant-derived cancer therapeutics
Impact of low and high lipopolysaccharide doses on the early expression of immune related genes and transcription factors in chicken macrophage-like HD11 cells
No full textInternational audienceThis study aimed to investigate how early transcriptional reprogramming of the chicken macrophage-like HD11 cell line differs when exposed to a low and high dose of lipopolysaccharide (LPS). Transcriptome analysis was performed on cells stimulated with 0, 3 and 300 ng/ml E. coli LPS for 5 h. After the processing steps, 10796 genes remained. Compared to the negative control, 11.8 and 16.3 % were upregulated at 3 and 300 ng and 25.8 and 44.1 % of the genes were downregulated. Subsequently, gene set enrichment analysis of Kyoto Encyclopedia of Genes and Genomes pathways demonstrated that, compared to the negative control, LPS at 3 and 300 ng/ml upregulated and downregulated similar pathways, out of which only three were significantly more affected at 300 than at 3 ng/ml LPS. These three enriched pathways were the toll-like receptor, cytokine-cytokine receptor interaction and C-type lectin receptor signalling pathways. Five transcription factors related to immune genes (PITX2, TCF7L2, NFIL3, NFATC1 and FOXO1) were downregulated at the high dose of LPS only and retrieved in the regulatory network between the differentially expressed immune related genes and transcription factors. Six other transcription factors were only retrieved in the 300 vs 3 ng/ml network: HMGB1, MEF2C, IKZF1, and PITXA, which were downregulated, and SRF and FOS, which were upregulated. These 11 transcription factors may account for the differences in the intensity of the cell response to low and high doses of LPS. Our results indicate that while the expression of transcription factors is largely similar, there are some differences between low and high doses of LPS. These differences could have implications when using LPS-stimulated HD11 cells as a model to study potential feed additives in poultry. Based on this knowledge we recommend considering the use of multiple LPS doses when using HD11 cells as an in vitro model to study the effects of dietary or pharmaceutical compounds on inflammation in chicken macrophages
The Tensor-Plus Calculus
No full textWe propose a graphical language that accommodates two monoidal structures: a multiplicative one for pairing and an additional one for branching. In this colored PROP, whether wires in parallel are linked through the multiplicative structure or the additive structure is implicit and determined contextually rather than explicitly through tapes, world annotations, or other techniques, as is usually the case in the literature. The diagrams are used as parameter elements of a commutative semiring, whose choice is determined by the kind of computation we want to model, such as non-deterministic, probabilistic, or quantum. Given such a semiring, we provide a categorical semantics of diagrams and show the language as universal for it. We also provide an equational theory to identify diagrams that share the same semantics and show that the theory is sound and complete and captures semantical equivalence. In categorical terms, we design an internal language for semiadditive categories (C,+,0) with a symmetric monoidal structure (C,x,1) distributive over it, and such that the homset C(1,1) is isomorphic to a given commutative semiring, e.g., the semiring of non-negative real numbers for the probabilistic case
Static and dynamic Monte Carlo simulations of phonon drag effects on thermoelectric properties in silicon nanostructures
No full textInternational audienceThermoelectric transport in silicon nanofilms is investigated using a self-consistent electro-thermal Monte Carlo simulator that couples electron dynamics to a phonon bath with spatially varying temperature. A key novelty of this work is the explicit inclusion of the phonon-drag contribution, implemented by modifying the electron-phonon momentum exchange based on the local deviation of the phonon distribution from equilibrium. The method is validated against bulk silicon data and extended to incorporate rough boundary scattering for both electrons and phonons, yielding excellent agreement with experimental measurements on nanofilms. We also analyze the transient regime and show that a temperature bias produces a slower current response than a voltage bias, although the phonon-drag effect itself tends to accelerate the response. These results demonstrate that the proposed framework provides a powerful tool for predicting both steady-state and time-dependent thermoelectric behavior in semiconductor nanostructures
Diagonal boundary conditions in critical loop models
No full textInternational audienceIn critical loop models, we define diagonal boundaries as boundaries that couple to diagonal fields only. Using analytic bootstrap methods, we show that diagonal boundaries are characterised by one complex parameter, analogous to the boundary cosmological constant in Liouville theory. We determine disc 1-point functions, and write an explicit formula for disc 2-point functions as infinite combinations of conformal blocks. For a discrete subset of values of the boundary parameter, the boundary spectrum becomes discrete, and made of degenerate representations. In such cases, we check our results by numerically bootstrapping disc 2-point functions. We sketch the interpretation of diagonal and non-diagonal boundaries in lattice loop models. In particular, a loop can neither end on a diagonal boundary, nor change weight when it touches it. In bulk-to-boundary OPEs, numbers of legs can be conserved, or increase by even numbers
Microbial life in Arctic pack ice: Prospects for the Tara Polaris expeditions
No full textInternational audienceSea ice, unlike freshwater ice, hosts abundant microbial life, thanks to the presence of liquid water inclusions encased within the ice matrix. The forthcoming Tara Polaris Expeditions (TPE), which will document drifting Arctic pack ice repeatedly over multiple years, together offer an unprecedented opportunity to advance understanding of the sea-ice microbiome -its diversity, variations, and ecological roles. In this contribution, we consider the current state of knowledge, identify key research gaps, and outline the potential for progress enabled by TPE. We envision the emergence of new insights into the seasonal evolution of microbial life, resolved at the floe (kilometric) scale, in relation to the evolution of the sea-ice environment -its morphology, light, temperature, and liquid water distribution and properties. Large potential lies in the characterization of diverse microhabitats across the central Arctic Ocean, associated with brine inclusions, pressure ridge cavities, and melt ponds. A major goal will be to document biological processes that remain poorly understood -colonization, diversity, functioning, interactions, and evolutionary dynamics -and that could benefit from the application of newly developed techniques. We argue that TPE is particularly timely, as the loss of multi-year ice may soon constrain opportunities to study life in this rapidly changing habitat
Characterization of the quantum state of top quark pairs produced in proton-proton collisions at = 13 TeV using the beam and helicity bases
No full textInternational audienceMeasurements of the spin correlation coefficients in the beam basis are presented for top quark-antiquark () systems produced in proton-proton collisions at = 13 TeV collected by the CMS experiment in 20162018, and corresponding to an integrated luminosity of 138 fb. The system is reconstructed from final states containing an electron or muon, and jets. Together with the previously reported results in the helicity basis, these measurements are used to decompose the system into the Bell and spin eigenstates in various kinematic regions. The spin correlation coefficients are also used to evaluate properties of the quantum state, such as the purity, von Neumann entropy, and entanglement. All results are consistent with standard model predictions
Confinement properties of zeolite-rich rocks with respect to water and various ionic tracers
No full textInternational audienceThe studied materials are zeolite-rich rocks (>70 wt% analcime, named analcimolite) forming a laterally continuous aquitard within the southern of the Tim Mersoï Basin (Niger). This unit, commonly referred to as the Abinky Formation, occurs as three mineralogical facies: a reduced facies containing Fe-chlorite, an oxidized facies with hematite, and an intermediate 'transition' facies. This analcimolite unit acts as an aquitard, separating the overlying and underlying sandstone aquifers, the latter locally providing potable water. Due to the low permeability of these analcime-rich rocks, diffusion is expected to be the dominant transport mechanism. However, no data on transport properties in zeolite-rich formations have been reported, and the mobility of water and ionic solutes remains unknown. This study aims to characterize diffusion in the three facies of the Abinky formation, identifying key controls on water and ion transport prior to any anthropogenic perturbation. Through-diffusion experiments using water tracers (HDO and HTO) showed that water diffusion (effective diffusion coefficient from 1.3 to 2 × 10 -11 m²/s) is primarily controlled by pore throat size rather than total porosity. A dual-porosity model was required, distinguishing a fast-transport network (open, low-tortuous zones) from a slow one (confined, tortuous zones). Despite variations in diffusion coefficients, all data are interpreted with capacity factors equal to total external porosity measured by water impregnation (excluding crystal water located in zeolite micropores). This confirms that water behaves as an inert tracer and that micropores contribute negligibly to water migration. For ionic tracers in reduced facies, 36 Cl -is partially excluded from external pores (anionic exclusion) and slightly adsorbed, with an extent of about 0.1 meq/100 g, a very small value compared to the cation exchange capacities of such rocks (up to ~40 meq/100 g for H+ and NH4+ ). In contrast, ²²Na⁺ exhibits strong adsorption due to isotopic exchange with 23Na+ in the analcime framework, leading to a diffusivity ~4 times higher than that of water. This dataset is a first step in constraining reactive transport models of water and solutes in zeolite-rich porous media under environmental conditions and prior to anthropogenic disturbance
Rheology of dense vibrated granular flows:non-monotonic response controlled by granular temperature
No full textWe study the rheology of dense granular materials subjected to vertical vibration using numerical simulations of a stress-imposed vane rheometer. The effective viscosity increases with confining pressure, decreases with vibration amplitude, and exhibits a non-monotonic dependence on frequency: weakening is observed at intermediate frequencies but is lost at high frequencies. We show that the rheological response is governed by the balance between grain-scale agitation energy and the stabilizing effect of confinement. This framework reconciles previously observed trends in viscosity and friction weakening and emphasizes the central role of energy injection and dissipation in determining granular flow properties under vibration
Bridging Language Phenotypes, Neural Dynamics and Gene Regulation in Autism
No full textAutism Spectrum Disorders (ASDs) affect approximately 1% of the global population, with prevalence rising over recent decades. While ASDs are strongly heritable (~70%), translating genetic findings into effective therapeutics remains challenging due to the vast number of implicated risk genes (>700) and their limited influence in disease expression. Current interventions remain symptom-focused and do not explicitly address underlying neurodevelopmental mechanisms. Emerging approaches in functional genomics offer new insights into ASD pathogenesis by exploring the diversity of gene expression, yet clinical applications remain distant. Language deficits are among the most frequent and disabling features of ASD, profoundly affecting the individual's and family's quality of life. Recent evidence from neuroimaging and electrophysiology studies suggest that disrupted and atypical neural oscillationsrhythmic brain activity patterns -dynamics are linked to language deficits in ASD.Importantly, several ASD-associated genes modulate brain oscillatory dynamics, pointing to a potential mechanistic link between genetic variation, altered brain rhythms, and language impairment. In this perspective article, we propose an imaging genetics framework that leverages neural oscillatory profiles as both endophenotypes relevant for targeted treatment and functional readouts of gene expression. Specifically, we advocate the use of neuromodulation to target and treat altered oscillatory dynamics underlying speech communication deficits in ASD, and the integration of oscillation-related ASD candidate genes into a new, symptom-oriented model of functional genomics. This approach illustrates how bridging genetic variation, non-invasive neuroimaging, and behavioral phenotypes can advance our understanding of ASD and inform the development of targeted, mechanism-based interventions.</p