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De Vleeschouwer, C.

Publications and source records attributed to De Vleeschouwer, C..

2 recordsLinked to original sources

MultiSpecies Canopy Segmentation: Interactive Machine-Learning and Pseudo-Labelling are key

This study investigates the challenge of creating datasets for training multiclass deep-learning segmentation models, specifically for segmenting multi-species canopy images. Creating training sets for deep-learning based segmentation of multispecies canopies is currently too labor-intensive and time-consuming to be viable. To address this challenge, we propose a novel pipeline that uses fully convolutional neural networks (FCNNs) to transition from single-species images to segmented multi-species images. This paper demonstrates that FCNNs can effectively generalize learning from single-species canopy images to multispecies canopy images, achieving accurate pixel classification in mixed species canopies even when the network was trained only on images of single-species canopies. Additionally, we introduce Interactive Machine Learning and pseudo labeling as a method for generating a single-species canopy training set in a matter of minutes. We also present two software packages to implement our approach and extensively evaluate them against several baselines. Our findings demonstrate that our approach can significantly reduce the human time load required for semantic segmentation of multispecies canopy images, achieving over 90% accuracy in less than 10 minutes. This new method has the potential to greatly facilitate the study of multispecies canopies.

bioengineering↗

Detecting Material State Changes in the Nucleolus by Label-free Digital Holographic Microscopy

Ribosome biogenesis is initiated in the nucleolus, a multiphase biomolecular condensate formed by liquid-liquid phase separation. The nucleolus is a powerful disease biomarker and stress biosensor whose morphology reflects its function. Here we have used digital holographic microscopy (DHM), a label-free quantitative phase contrast microscopy technique, to detect nucleoli in adherent and suspension cells. Subtle nucleolar alterations induced by drug treatment or by depletion of ribosomal proteins were efficiently detected by DHM. We trained convolutional neural networks to detect and quantify nucleoli automatically on DHM images of cultured human cells (HeLa). Holograms containing cell optical thickness information allowed us to define a novel nucleolar index which we used to distinguish nucleoli whose material state had been optogenetically modulated. We conclude that DHM is a powerful tool for quantitatively characterizing nucleoli, including material state, without any staining.

cell biology↗