J Geophys Res Space Phys
January 2022
We develop an open source algorithm to apply ransfer learning to urora image classification and agnetic disturbance valuation (TAME). For this purpose, we evaluate the performance of 80 pretrained neural networks using the Oslo Auroral THEMIS (OATH) data set of all-sky images, both in terms of runtime and their features' predictive capability. From the features extracted by the best network, we retrain the last neural network layer using the Support Vector Machine (SVM) algorithm to distinguish between the labels "arc," "diffuse," "discrete," "cloud," "moon" and "clear sky/ no aurora".
View Article and Find Full Text PDFGlycosyltransferases (GTs) constitute a very large multi-gene superfamily, containing several thousand members identified in sequenced organisms especially in plants. GTs are key enzymes involved in various biological processes such as cell wall formation, storage polysaccharides biosynthesis, and glycosylation of various metabolites. GTs have been identified in rice (Oryza sativa) and Arabidopsis thaliana, but their precise function has been demonstrated biochemically for only a few.
View Article and Find Full Text PDFBackground: A major challenge is to understand how the walls of expanding plant cells are correctly assembled and remodeled, often in the presence of wall-degrading micro-organisms. Plant cells, like yeast, react to cell-wall perturbations as shown by changes in gene expression, accumulation of ectopic lignin, and growth arrest caused by the inhibition of cellulose synthesis.
Results: We have identified a plasma-membrane-bound receptor-like kinase (THESEUS1), which is present in elongating cells.
Phosphatidylinositol-specific phospholipase C (PI-PLC) activity is a potential virulence factor and is exhibited only by the Listeria species Listeria monocytogenes and Listeria ivanovii. A chromogenic substrate for the direct detection of PI-PLC activity is available in a new medium (BCM L. monocytogenes plating agar).
View Article and Find Full Text PDFIsolated mesophyll cells from Zinnia elegans are induced by auxin and cytokinin to form tracheary elements (TEs) in vitro with high synchrony. To reveal the changing patterns of gene expression during the 48 h of transdifferentiation from mesophyll to TE cell fate, we used a cDNA-amplified fragment length polymorphism approach to generate expression profiles of >30,000 cDNA fragments. Transcriptional changes of 652 cDNA fragments were observed, of which 304 have no previously described function or sequence identity.
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