Publications by authors named "A Deniset-Besseau"

Photothermal atomic force microscopy-infrared (AFM-IR) enables label-free chemical imaging and spectroscopy with nanometer-scale spatial resolution through the integration of atomic force microscopy (AFM) and infrared radiation. The capability for subsurface and three-dimensional (3D) tomographic material analysis remains, however, largely unexplored. Here, we establish a simple and robust empirical relationship between the probing depth and laser repetition rate for three important modes of AFM-IR operation: resonance-enhanced, tapping, and surface-sensitive AFM-IR.

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The smallest entities in aquatic ecosystems, i.e., femtoplankton, are certainly the largest reservoir of uncharacterized biodiversity.

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Primordial carbon delivered to the early earth by asteroids and meteorites provided a diverse source of extraterrestrial organics from pre-existing simple organic compounds, complex solar-irradiated macromolecules, and macromolecules from extended hydrothermal processing. Surface regolith collected by the Hayabusa2 spacecraft from the carbon-rich asteroid 162173 Ryugu present a unique opportunity to untangle the sources and processing history of carbonaceous matter. Here we show carbonaceous grains in Ryugu can be classified into three main populations defined by spectral shape: Highly aromatic (HA), Alkyl-Aromatic (AA), and IOM-like (IL).

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Article Synopsis
  • The study focuses on creating supramolecular networks using organic molecules on surfaces, aiming to develop complex and functional multilayers instead of just monolayers.
  • The research combines scanning probe microscopies and atomic force microscopy-infrared (AFM-IR) to analyze how these molecular arrangements change from 2D to 3D on a HOPG surface.
  • The findings show that the infrared spectra change between layers due to variations in the angles between certain molecular groups, highlighting how layer interactions can affect molecular conformation.
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M145 is a model strain extensively studied to elucidate the regulation of antibiotic biosynthesis in species. This strain abundantly produces the blue polyketide antibiotic, actinorhodin (ACT), and has a low lipid content. In a process designed to delete the gene encoding the isocitrate lyase () of the glyoxylate cycle, an unexpected variant of was obtained besides deletion mutants.

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