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Signals from the NWC ground‐based very low frequency (VLF) transmitter can leak into the magnetosphere and scatter trapped energetic electrons into drift loss cones. Recent studies also suggest that cosmic ray albedo neutron decay (CRAND) is probably an important source for quasi‐trapped electrons in the inner belt. To investigate their relative contributions, this study comprehensively analyzes the long‐term variations of quasi‐trapped 206 keV electrons at L = 1.7, which is roughly the L shell where NWC is located. Furthermore, a drift‐diffusion‐source model is used to reproduce longitudinal distributions of quasi‐trapped electrons and investigate sensitivities of simulation results to VLF transmitter intensities. These results suggest that CRAND is the main source of quasi‐trapped hundreds of keV electrons when the NWC station is at dayside. In contrast, pitch angle diffusions become the main source mechanism of these quasi‐trapped electrons when the NWC station operates at nightside with more VLF transmitter energy leaking into the magnetosphere. Plain Language Summary: Very low frequency (VLF) signals emitted from NWC transmitter locating at west Australia are used for submarine communications. The VLF signals propagate along the Earth‐ionosphere waveguide and a portion can leak into the magnetosphere. Low‐Earth orbit satellite observations demonstrate that the NWC transmitter signals in the magnetosphere can scatter trapped energetic electrons into the drift loss cone at L = 1.7, which is roughly of the L shell of the NWC location, resulting in the enhancement of approximately 200 keV quasi‐trapped electron fluxes. Cosmic ray albedo neutron decay (CRAND) describes the process that galaxy cosmic rays (the majority consist of high‐energy protons and helium nucleus) collide with atmosphere atoms and produce albedo neutrons, which have a mean lifetime of 887 s and then decay into protons, electrons, and antineutrinos, which is also considered as a source of >200 keV quasi‐trapped electrons in the inner belt. In this study, we compare the model results with DEMETER measurements and find that CRAND is the main source of quasi‐trapped hundreds of keV electrons when the NWC transmitter is at dayside. In contrast, the pitch angle diffusion induced by NWC transmitter signals becomes the main source mechanism of these quasi‐trapped electrons due to VLF signals leaking into the magnetosphere easily when the NWC transmitter operates at nightside. Key Points: CRAND is the main source of 200–700 keV quasi‐trapped electrons at L = 1.7 when NWC transmitter is at daysideFor quasi‐trapped 206 keV electrons at L = 1.7, pitch angle diffusion is the main source mechanism when NWC station operates at nightsideThe 〈Dαα〉 $\langle {D}_{\alpha \alpha }\rangle $ from NWC needs to be approximately 10−6 to 10−5 s−1 to reproduce the satellite observations of quasi‐trapped 206 keV electrons at L = 1.7 [ABSTRACT FROM AUTHOR]

Over the last two decades, extensive studies have been performed at the molecular level to understand the evolution of carnivorous plants. As fruits, the repertoire of protein components in the digestive fluids of several carnivorous plants have gradually become clear. However, the quantitative aspects of these proteins and the expression mechanisms of the genes that encode them are still poorly understood. In this study, using the Australian sundew Drosera adelae, we identified and quantified the digestive fluid proteins. We examined the expression and methylation status of the genes corresponding to major hydrolytic enzymes in various organs; these included thaumatin-like protein, S-like RNase, cysteine protease, class I chitinase, β-1, 3-glucanase, and hevein-like protein. The genes encoding these proteins were exclusively expressed in the glandular tentacles. Furthermore, the promoters of the β-1, 3-glucanase and cysteine protease genes were demethylated only in the glandular tentacles, similar to the previously reported case of the S-like RNase gene da-I. This phenomenon correlated with high expression of the DNA demethylase DEMETER in the glandular tentacles, strongly suggesting that it performs glandular tentacle-specific demethylation of the genes. The current study strengthens and generalizes the relevance of epigenetics to trap organ-specific gene expression in D. adelae. We also suggest similarities between the trap organs of carnivorous plants and the roots of non-carnivorous plants., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology.)