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Abstract: Large Igneous Province (LIP) volcanism is a major driver of past global change via degassing of large volumes of climate-altering and poisonous gases (such as H₂O, CO₂, CH₄, SO2). These volatile species can produce contrasting effects on the atmosphere, from long-term global warming to short-lived volcanic winters. We know from historical cases (e.g., the 1783–84 Laki fires, the 1991 Pinatubo eruption) that sulfur-rich eruptions can produce global cooling with societal consequences. In deep time, repeated volcanic winters occurring during LIP emplacement, superimposed on long-term warming, could have stressed ecosystems and contributed to mass extinction, but their short duration makes them difficult to detect in the stratigraphic record (Callegaro et al., 2020; 2023; Kent et al., 2024). Sedimentary proxies of short-term cooling such as glendonite crystallization are being explored, but their signals remain ambiguous (Vickers et al., 2020). We propose a complementary, “within-magma” approach for tracing sulfur-rich magmatic pulses capable of generating volcanic winters. Using synchrotron X-ray microfluorescence, we measure sulfur concentrations in clinopyroxene from LIP magmas, and calculate equilibrium melt concentrations with established partition coefficients. Since clinopyroxene is an early and almost ubiquitous phase in LIPs magmas, this method allows the detection of variations in sulfur budgets throughout the stratigraphy of a lava pile, identifying intervals of sulfur-rich lavas as potential drivers of volcanic winters. We discuss future developments of the method, and results obtained for magmas of the Deccan Traps (Western Ghats lava pile, India), and Franklin large igneous province.

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Abstract: The integration of nanoencapsulation techniques with foliar application presents a promising approach to enhance selenium (Se) biofortification in agriculture. This study examined the foliar uptake of liposome-encapsulated Se in wheat leaves (Triticum aestivum) using synchrotron-based micro-X-ray fluorescence (μ-XRF) and confocal microscopy. μ-XRF mapping showed Se accumulation at leaf edges after 24 h, suggesting initial uptake via stomata, while free Se was absorbed and transported more rapidly, highlighting the slow-release effect provided by liposomal encapsulation, longer than the analyzed time. No immediate translocation of Se to the stem was observed, suggesting that more time is required for this internal movement. Micro-X-ray absorption near-edge structure (μ-XANES) speciation analysis demonstrated that Se was metabolized into organic forms within the plant. Finally, confocal fluorescence microscopy confirmed liposome absorption through the plant surface within 24 h, corroborating the μ-XRF findings. These results are crucial for optimizing liposome formulation to maximize Se transfer to edible parts.

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Abstract: Understanding the impact of volcanic eruptions on climate over the last two millennia is essential to place current anthropogenic climate change into a long-term context. High-resolution proxy archives are crucial for this purpose, yet their availability decreases rapidly back in time. Besides ice cores, speleothems and corals, tree rings represent a uniquely valuable archive, providing records with annual resolution of past-climate change. Volcanic eruptions are among the most impactful natural forcings on Earth’s climate, through the injection of gaseous plumes into the atmosphere that can induce warming or cooling of the planet surface. While some of these impacts are well-known and studied, there are many older volcanic events whose details are unknown or uncertain, due to the lack of direct historical evidence. Volcanic plumes transport volatile elements (e.g., S, Fe, Zn, Cu, Hg) that can be absorbed by trees and recorded in the yearly tree-ring layers. So far, dendrochemistry has been widely applied to assess anthropogenic pollution, but our research explores its potential as a novel proxy: by identifying chemical spikes of these elements in tree rings of known age, it may be possible to correlate them with known volcanic eruptions or identify previously unrecognized volcanic events. Here we present data obtained at Diamond synchrotron on tree rings from juniper (Juniperus communis) samples from Kevo, Finland, whose dendrochronological records extend back to the early Middle Ages. These measurements revealed distinct peaks in metal elements such as Zn and Cu, which are typically enriched in volcanic plumes and can be hosted in the wood as semi-nutrients. Some concentration peaks detected in the tree rings correspond to the ages of major Icelandic eruption from the lower Middle Ages. These preliminary results suggest that dendrochemical analyses may provide a new archive of past volcanic activity. If validated, this approach could significantly improve reconstructions of volcanic eruptions of the past and corresponding climate variability over the last two millennia.

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Abstract: Metal–organic frameworks (MOFs) are entering water technologies on the premise that abiotic stability predicts ecological safety. We overturn this assumption by showing that UiO-66 – often regarded as chemically and structurally robust – remains intact after 7-day aging in natural borehole water yet undergoes rapid in vivo transformation in Daphnia magna. Synchrotron Microfocus X-ray absorption spectroscopy (XAS) revealed collapse of the ordered Zr–carboxylate coordination into disordered Zr–O environments within the gut; Extended X-ray Absorption Fine Structure (EXAFS) showed loss of second-shell features, and Transmission Electron Microscopy (TEM) confirmed loss of crystallinity with nanoscale aggregates appearing within 24 h of ingestion. Although acute immobilization was limited (48 h EC50 ≈ 26.5 μg mL–1), a sublethal, environmentally relevant exposure (10 μg mL–1) caused pronounced chronic effects: brood initiation was delayed by 3–5 days and cumulative reproduction decreased by ∼74% without mortality. We attribute these outcomes to gut-level transformation and associated energetic/physiological burdens, not captured by standard acute tests. These results show that abiotic stability does not necessarily imply biological inertness and highlight the need to integrate in vivo transformation pathways with chronic end points in environmental risk assessment for water-sector materials. This perspective provides a mechanistic basis to inform Safe-and-Sustainable-by-Design (SSbD) MOFs before widespread deployment in water treatment.

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Abstract: Rice is a staple food for over half the world's population. This study uniquely investigates the spatial distribution of key micronutrients (Cu, Mn, Fe, Zn) in cooked brown, white, and parboiled rice using Synchrotron Micro-X-ray Fluorescence (sXRF) for the first time. Complementary analysis with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) validates bulk elemental concentrations. Results from this dual-approach study reveal significantly higher micronutrient concentrations in brown rice compared to white or parboiled rice, with nutrients predominantly localised in the peripheral layers and minimal presence in the endosperm. Notably, sXRF imaging identified nutrient-rich pockets within the grain periphery, offering new perspectives on nutrient distribution beyond peripheral accumulation. Additional insights include the impact of rice section thickness (50 and 150 μm) and beam dwell times (0.5 and 30s) on sXRF sensitivity and resolution, highlighting trade-offs in detection capabilities, advancing our understanding of micronutrient localisation in cooked rice.