Even in an era where 8-meter class telescopes are common, small telescopes are considered very valuable research facilities since they are available for rapid follow-up or long term monitoring observations. To maximize the usefulness of small telescopes in Korea, we established the SomangNet, a network of 0.4{1.0 m class optical telescopes operated by Korean institutions, in 2020. Here, we give an overview of the project, describing the current participating telescopes, its scientic scope and operation mode, and the prospects for future activities. SomangNet currently includes 10 telescopes that are located in Australia, USA, and Chile as well as in Korea. The operation of many of these telescopes currently relies on operators, and we plan to upgrade them for remote or robotic operation. The latest SomangNet science projects include monitoring and follow-up observational studies of galaxies, supernovae, active galactic nuclei, symbiotic stars, solar system objects, neutrino/gravitational-wave sources, and exoplanets.

We investigated the detoxification strategies of Helicoverpa armigera and Heliothis virescens, which allow them to feed successfully on cotton plants that produce toxic gossypol as a chemical defense compound. First, we tested CYP6AE14, a proposed candidate enzyme for gossypol detoxification, for its ability to detoxify gossypol. In incubation assays with gossypol and heterologously expressed CYP6AE14 no metabolites were detected. Our data show that CYP6AE14 is not directly involved in gossypol metabolism, at least under the assay conditions tested, but rather takes part in the general stress response of the herbivores to plant toxins. Second, we discovered that H. armigera and H. virescens excrete a large proportion (50%) of unmetabolized gossypol in the feces, but additionally metabolize gossypol by glycosylation. Analysis of larval feces revealed three monoglycosylated and up to five diglycosylated gossypol isomers when larvae fed on gossypol-supplemented diet. Based on their expression patterns we selected H. armigera candidate UGT genes and functionally expressed the respective proteins in insect cells. In enzymatic assays, we showed that UGT41B3 and UGT40D1 are capable of glycosylating gossypol mainly to a diglycosylated gossypol isomer that is characteristic for H. armigera and is absent in H. virescens feces. We offer novel insights into the detoxification mechanism of the plant defensive toxin, gossypol, by two generalist herbivores.

Polycyclic aromatic hydrocarbons (PAHs) in Galactic planetary nebulae (PNe) are investigated by means of the unidentified infrared (UIR) bands. Continuous near- to mid-infrared spectra of PNe are obtained with the AKARI/IRC and the Spitzer/IRS. All 19 PNe in the present study show prominent dust emissions and we investigate the variation in the intensity ratios among the UIR bands. The ionization fraction and the size distribution of PAHs in PNe are derived using the UIR band ratios. We find that the ionization fraction of PAHs in PNe is around 0.0-0.6 and that small PAHs are scarce. The present result indicates a systematic trend of the 3.4 μm aliphatic feature to become weak as the PAH ionization fraction increases.