Publications by authors named "R Tucoulou"

This work shows that the plastic debris accumulated along with stranded Sargassum biomass in Guadeloupe's beaches contains different forms of arsenic. Results from synchrotron nano X-ray Fluorescence (nanoXRF) and nano X-ray Absorption Near Edge Structure (nanoXANES) show that arsenate (As(V) in a tetrahedral coordination) present in seawater is complexed in the algae cell walls in an octahedral As(V) form, which is subsequently reduced to As(III) within the algae. Inorganic As(III) is either excreted or may undergo methylation and/or binding to glutathione, which is then stored in the algal cells or excreted.

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Assessing the impact of potentially toxic elements (PTEs) on coastal waters requires understanding their interaction with seaweeds, as they are foundational organisms in nearshore ecosystems. While seaweeds are known to accumulate PTEs, information on the mechanisms and locations of this accumulation is very limited. We employed synchrotron-based X-ray fluorescence (S-XRF) to map the distribution of various chemical elements at nanometric resolution in Fucus vesiculosus, a brown alga dominant in intertidal zones.

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Article Synopsis
  • Controlling how effectively electrocatalysts convert carbon dioxide into useful chemicals is difficult due to factors like bulk and surface lattice strain.
  • This study uses advanced imaging techniques to analyze the dynamic behavior of Cu-Ag tandem catalysts, creating three-dimensional strain maps based on varying electrical conditions and product outputs.
  • Results show that adding moderate amounts of silver improves the stability of the catalyst and reduces unwanted hydrogen production, highlighting the significance of using advanced spectroscopy methods for better understanding these catalysts.
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Particles released from cobalt-chromium-molybdenum (CoCrMo) alloys are considered common elicitors of chronic inflammatory adverse effects. There is a lack of data demonstrating particle numbers, size distribution and elemental composition of bone marrow resident particles which would allow for implementation of clinically relevant test strategies in bone marrow models at different degrees of exposure. The aim of this study was to investigate metal particle exposure in human periprosthetic bone marrow of three types of arthroplasty implants.

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Photosymbiosis is widespread and ecologically important in the oceanic plankton but remains poorly studied. Here, we used multimodal subcellular imaging to investigate the photosymbiosis between colonial Collodaria and their microalga dinoflagellate (Brandtodinium). We showed that this symbiosis is very dynamic whereby symbionts interact with different host cells via extracellular vesicles within the colony.

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