Publications by authors named "J J Drevon"

In the widely accepted 'unified model' solution of the classification puzzle of active galactic nuclei, the orientation of a dusty accretion torus around the central black hole dominates their appearance. In 'type-1' systems, the bright nucleus is visible at the centre of a face-on torus. In 'type-2' systems the thick, nearly edge-on torus hides the central engine.

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Article Synopsis
  • - Sulfur (S) and phosphorus (P) are crucial for plant growth, affecting nitrogen fixation and nodule development in legumes, with S distribution providing insight into its role in these processes.
  • - Research involved analyzing nodules from plants grown with different P levels, using synchrotron micro-X-ray fluorescence to map S in nodule tissues, revealing a significant concentration of S in the middle cortex of both determinate and indeterminate nodules.
  • - Findings showed that P deficiency led to a decrease in S fluorescence intensity and highlighted distinct distributions of magnesium (Mg) and chloride (Cl) within the nodule, indicating S's role in ionic balance and influencing nodule permeability to oxygen.
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While increased P-hydrolysing acid phosphatases (APase) activity in bean nodules is well documented under phosphorus (P) limitation, gene expression and subcellular localization patterns within the N-fixing nodule tissues are poorly understood. The aim of this research was to track the enzyme activity along with the intra-nodular localization of fructose-1,6-bisphosphatase (FBPase), and its contribution to P use efficiency (PUE) under symbiotic nitrogen fixation (SNF) in Phaseolus vulgaris. The FBPase transcript were localized in situ using RT-PCR and the protein activity was measured in nodules of two contrasting recombinant inbred lines (RILs) of P.

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Symbiotic nitrogen fixation (SNF) in root nodules of grain legumes such as chickpea is a highly complex process that drastically affects the gene expression patterns of both the prokaryotic as well as eukaryotic interacting cells. A successfully established symbiotic relationship requires mutual signaling mechanisms and a continuous adaptation of the metabolism of the involved cells to varying environmental conditions. Although some of these processes are well understood today many of the molecular mechanisms underlying SNF, especially in chickpea, remain unclear.

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