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Climatic and environmental impacts on source-to-sink processes in SW Taiwan since the last deglaciation
No full textInternational audienceIn recent decades, many scientific studies have been conducted to constrain present and past source-to-sink processes and their controlling factors. The role of typhoon and monsoon summer rainfall on chemical weathering and soils erosion in east Asia is still not well established. Clay minerals and major elements, combined with Nd and Sr isotopic compositions were analyzed on sediments from Core MD18-3569 located close to the Penghu Canyon on the Taiwan margin (northeastern South China Sea) in order to establish climatic and environmental controls on source-to-sink processes and weathering history of small river basins of southwest Taiwan since the last glacial period. The 87Sr/86Sr ratios and ɛNd values of the detrital and clay fractions combined with the high content of illite and chlorite suggest that the mountainous rivers of southwest Taiwan are the main sources of sediments to the Taiwan margin since the last deglaciation. Such results permit to evaluate past intensity of chemical weathering in the rivers of southwest Taiwan from major elements composition and clay mineral assemblages. The long-term changes of chemical weathering intensity in Taiwan are driven by the variations of east Asian summer monsoon rainfall. During the deglaciation, the progressive strengthening of rainfall enhanced the chemical weathering intensity which peaked in the early Holocene. The Holocene is characterized by a decrease of the chemical weathering degree of sediments derived from Taiwan. This coincides with the weakening of summer monsoon rainfall, an increase in typhoon activity, and changes in vegetation cover in southwest Taiwan. These processes caused soil destabilization and erosion, regressive pedogenesis, and weaker chemical weathering intensity. This was due to the shorter residence time of sediments in the soils of southwest Taiwan. Our multi-proxy study highlights the strong link between summer monsoon and typhoon rainfalls, environmental changes, and chemical weathering history in Taiwan
Unveiling the relationship between the energy released during thermal runaway of Li-ion cells and their stored electrical energy
No full textInternational audienceThe use of lithium-ion (Li-ion) batteries has rapidly increased due to improvements in performance, durability, and cost-effectiveness, driven by the growth of electric vehicles (EVs), renewable energy storage, and portable electronics. High energy density, long cycle life, and low self-discharge rate are key factors behind this evolution. However, the safety of Lithium-ion batteries remains a major concern due to the potential risk of thermal runaway, which can result in fast heat release, the ejection of particles and gases, and possibly fire and explosion. Therefore, the reliable characterization of thermal runaway energy and gas volume release is essential for incorporating thermal runaway mitigation into the design phase of battery modules. In this study, 29 thermal runaway tests of large-capacity prismatic and pouch NMC cells were analysed to generate thermal runaway energy and gas volume release. It was found that thermal runaway energy, when normalized by the electrical energy of the cell at the time thermal runaway occurs, was constant during all the tests performed under vacuum and inert atmosphere. The constant was equal to 1.25. Similarly, the normalized number of moles generated during thermal runaway remained constant at 4.9 x 10-3 mol·kJ-1. When the tests were conducted in air, the large quantity of oxygen available led to additional combustion and energy release. The normalized thermal runaway energy increased to 5.0, while the normalized number of moles decreased to 4.2 10-3 mol·kJ-1. The two conditions-under vacuum and in air- represent the two cases limiting the access of air in a typical battery module configuration, therefore the data presented in this work can be useful for evaluating thermal runaway propagation and casing integrity in a battery module during the design phase
First observation of the charmless baryonic decay
No full textInternational audienceA search for the charmless baryonic decay is performed using proton-proton collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 5.4~. The branching fraction for this decay is measured for the first time relative to that of the topologically similar decay , with . The branching fraction is measured to be \mbox{}, where the first uncertainty is statistical, the second is systematic, and the third arises from the uncertainty in the normalization channel branching fraction. The asymmetry is measured to be , where the uncertainties are statistical and systematic. The background-subtracted invariant-mass distributions of and pairs exhibit pronounced enhancements at both kinematic thresholds, in contrast to a uniform phase-space distribution
First observation of violation and measurement of polarization in decays
No full textInternational audienceAn amplitude analysis of the decay is performed in the mass regions and , using collision data recorded with the LHCb detector corresponding to an integrated luminosity of . The polarization fractions and asymmetries for decays are measured. Violation of the symmetry in the decay is observed for the first time, with a significance exceeding nine standard deviations. The asymmetry is measured to be and the -averaged longitudinal polarization fraction of . The measurements help to shed light on the polarization puzzle of mesons decaying to two vector mesons
Fragmentation of the IAR along the chains and
No full textInternational audienceWe study Isobaric Analog Resonances in even-even nuclei along the isotonic chain. First, Hartree-Fock-Bogoliubov calculations, using the Gogny D1M effective interaction, have been performed to provide energies and occupation probabilities of nucleon orbitals. The Isobaric Analog Resonances are calculated with the charge exchange QRPA approach on top of then HFB calculations. Fermi transition mechanism is interpreted with the existence of collective modes in the final nucleus. The fragmentation of the Fermi Strength results from the fractional occupation of nucleon shells, a direct consequence of nuclear pairing. The theoretical Fermi transition probabilities along the isotopic chain are also analyzed and confirm our conclusions
Community-Curated Galaxy Interfaces with the Galaxy Labs Engine
No full textThe Galaxy platform is a globally distributed environment for data-intensive research, providing thousands of analysis tools across major public servers. However, this decentralised ecosystem presents usability challenges for both users and administrators, particularly in surfacing relevant tools and workflows for specific communities. To improve discoverability and support global collaboration, the Galaxy project has employed community-driven "Galaxy Flavours"—subdomains with curated content for defined research domains. While conceptually valuable, Flavours suffer from critical limitations: they are statically deployed, difficult to replicate across servers, and often provide inconsistent and unintuitive user interfaces.To address these challenges, we developed the Galaxy Labs Engine (GLE), a service that enables the creation of Galaxy Labs. This new paradigm enables globally synchronised, domain-specific entry points built from structured, reusable web content. GLE separates content from deployment, allowing communities to define a shared canonical representation of their domain, while enabling individual Galaxy servers to locally customise presentation. Labs are designed to guide users through curated tools, workflows, and training resources, and are aimed at researchers who are new to the analytical methods or technologies specific to the domain.The Galaxy Labs Engine provides a consistent, customisable, and community-driven interface layer for the Galaxy ecosystem. By fostering FAIR principles, Labs offer a scalable improvement to Flavours and enhance Galaxy’s ability to support diverse research communities. GLE is open-source and currently deployed at https://labs.usegalaxy.org.au, with multiple Labs already supporting active user groups. This work strengthens Galaxy’s role as a collaborative platform for reproducible, user-centered science
Reduction in Earth’s carbon budget imbalance
No full textInternational audienceThe Global Carbon Project (GCP) compiles an updated global carbon budget each year, synthesizing state-of-the-art estimates of anthropogenic CO 2 emissions, land and ocean sinks, and the atmospheric CO 2 growth rate. The residual between these terms, referred to as the global carbon budget imbalance, reflects the aggregate inaccuracies of the individual component estimates. Growth rates derived from marine boundary layer (MBL) surface flask mixing ratio observations are assumed to be highly accurate. Hence, land and ocean sink estimates from process models are viewed as the primary source of the imbalance. Here we show that substantial discrepancies arise when marine boundary layer growth rate estimates are used to represent the whole atmosphere. Correcting for this discrepancy using atmospheric flux inversion estimates reduces the 0.76 petagrams of carbon per year (PgC yr -1 ) root-mean-square (RMS) imbalance (from the 2023 GCP report) by up to 25%. Further investigation into the imbalance metric between the 2017 and 2023 GCP reports shows a reduction in imbalance resulting from updates to each carbon budget component, leading to a 16% overall reduction. These reductions provide quantitative evidence of improvements in process models and inventory emission estimates, driven by enhanced forcing data and the inclusion of new carbon cycle processes. Overall, we report a 37% reduction in the root-mean-square imbalance, from 0.91 to 0.57 PgC yr -1 , between the 2017 and 2023 GCP reports by combining process model and inventory improvements with atmospheric growth rate corrections. Our findings indicate that land and ocean process models are more accurate than previously believed and that the scientific understanding of Earth's carbon cycle is improving.Accurate quantification of anthropogenic carbon dioxide (CO 2 ) emissions and their redistribution among Earth's major carbon reservoirs (atmosphere, oceans, and terrestrial biosphere) is essential for tracking mitigation progress, informing climate policy, and projecting future climate trajectories 1-3 . As global temperatures rise and the impacts of climate change intensify, the scientific community is refining observational and modeling tools to constrain each component of the carbon cycle. The Paris Agreement's five-year Global</div
Accuracy of tracer-based methane flux quantification: underlying impact of calibrating acetylene measurements
No full textInternational audienceFacility-scale methane emission fluxes can be derived by comparing tracer and methane mole fraction measurements downwind of a methane emission source, where a co-located tracer gas is released at a known flux rate. Acetylene is a commonly used methane tracer due to its availability, low cost and low atmospheric background. Acetylene mole fraction can be measured using infrared gas analysers such as the cavity ring-down spectroscopy Picarro G2203. However, failure to calibrate tracer gas analysers may influence methane flux estimation, due to inaccurate raw tracer mole fraction measurements. We conducted extensive Picarro G2203 laboratory characterisation testing. Picarro G2203 acetylene measurements were calibrated by diluting a high concentration of acetylene with ambient air. The precise level of acetylene in each dilution blend was determined by diluting a high-concentration methane source in an identical way, with reliable methane mole fraction measurements used to quantify the true level of dilution. A linear calibration fit applied to raw acetylene mole fraction measured by the Picarro G2203 showed that these measurements could be corrected through direct multiplication with a calibration gain factor of 0.94. However, this specific calibration for the Picarro G2203 tested in this study is only valid from an acetylene mole fraction of 1.16 ppb, below which unstable measurements were observed. The same Picarro G2203 was used during a field study to perform 14 successful transects downwind of an active landfill site, where a point-source acetylene release was conducted at a fixed flow rate. Methane fluxes were derived by integrating the methane and acetylene mole fraction plumes, as a function of distance along the sampling road. This resulted in a ±56 % flux variability between different transects which was principally due to errors associated with the tracer release location and downwind sampling positioning. Methane fluxes were also derived using raw uncalibrated Picarro G2203 acetylene mole fraction instead of calibrated measurements, which resulted an average methane emission flux underestimation of approximately 8 % for this specific study, compared to fluxes derived using calibrated measurements. Unlike a random uncertainty, this bias represents a consistent flux underestimation that cannot be reduced by improving the field sampling methodology; the only solution is using calibrated acetylene mole fraction measurements. The magnitude of the bias is principally due to the 0.94 multiplicative gain factor. Therefore, a similar level of methane flux bias can be expected in other studies when using uncalibrated acetylene mole fraction measurements from the Picarro G2203 tested in this work. This study therefore emphasises the equal importance of calibrating target as well as tracer gas measurements, regardless of the instrument being used to obtain these measurements. Otherwise, biases can be induced within target gas flux estimates. For the example of methane, this can influence our understanding of the role of certain facility-scale sources within the global methane budget
High-Temperature Dual-Rail Contactless MEMS Logic for Industrial Edge Computing
No full textInternational audienceSensors are advancing to integrate smart functionalities within the same package to enhance data sensing capabilities. However, implementing in-sensor computing at high temperatures is challenging due to CMOS limitations. To overcome this, we introduce the first demonstration of electromechanical computing using a process flow similar to conventional MEMS sensors, enabling seamless in-MEMS-sensor computing at elevated temperatures. Our approach uses a contactless mechanism, addressing the reliability issues of existing digital circuits based on MEMS relays and ensuring durability under significant temperature fluctuations. We demonstrate NOT logic operation as well as state propagation through a cascade of 10 pipelined gates, paving the way for digital processing within the MEMS sensor's physical layer. Additionally, our devices operate at temperatures up to at least 473 K, opening new possibilities for in-sensor computing in extreme environments
Bridging experiments and models, towards a new paradigm : DROP-PINN, a physics-informed neural network to predict droplet rupture in multiphase systems
No full textInternational audienceA fast and robust PINN-based algorithm is introduced to model turbulent breakage• DROP-PINN infers breakage frequencies directly from image sequences of droplets.• The methodology, based on various simulated configurations, is caseindependent• The DROP-PINN performance is demonstrated by dedicated stirred tank experiments</div