Timely information about landslides during or immediately after an event is an invaluable source for emergency response and management. Using an active sensor, synthetic aperture radar (SAR) can capture images of the earth’s surface regardless of weather conditions and may provide a solution to the problem of mapping landslides when clouds obstruct optical imaging. The 2018 Hokkaido Eastern Iburi earthquake (Mw 6.6) and its aftershocks not only caused major damage with severe loss of life and property but also induced many landslides across the area. To gain a better understanding of the landslides induced by this earthquake, we proposed a method of landslide mapping using pre- and post-event Advanced Land Observation Satellite 2 Phased Array L-band Synthetic Aperture Radar 2 (ALOS-2 PALSAR-2) images acquired from both descending and ascending orbits. Moreover, the accuracy of the classification results was verified by comparisons with high-resolution optical images, and ground truth data (provided by GSI, Japan). The detected landslides show a good match with the reference optical images by visual comparison. The quantitative comparison results showed that a combination of the descending and ascending intensity-based landslide classification had the best accuracy with an overall accuracy and kappa coefficient of 80.1% and 0.45, respectively.

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Selective laser melting (SLM) is an ideal method to directly fabricate products with high geometrical complexity. With low density and good corrosion resistance, aluminum alloys are widely used as important structural materials. Microstructures and mechanical properties of SLMed aluminum alloys have been recently widely studied. Corrosion behavior as a vital concern during the service of SLMed aluminum alloy parts has also drawn many attentions. Previous studies have found that SLM-processed aluminum alloys exhibit better corrosion resistance compared to the casted and wrought counterparts for both Al-Si alloys and high strength 2xxx Al alloys, which is mainly due to the unique microstructure features of SLMed Al alloys. For Al-Si alloys, with different shapes of Si networks, the different building planes show discrepant corrosion behaviors. Owing to the rougher surface with relatively larger numbers of defects, the as-printed surface is vulnerable to corrosion than the polished. Heat treatment has a negative effect on corrosion resistance due to the breakup of Si networks. The microstructure features correlated with the corrosion behaviors were also reviewed in this paper. Some suggestions on the future study of corrosion behaviors of SLMed Al alloys were put forward.

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To develop a plant expression system for the production of the human papillomavirus type 16 (HPV16) vaccine, we investigated whether the HPV16 L1 protein can be expressed in tobacco plants and whether it can be used as the cheapest form of edible vaccine. The HPV16 L1 coding sequence was amplified by PCR using specific primers from the plasmid pGEM-T-HPV16 containing the template sequence, and subcloned into the intermediate vector pUCmT and binary vector pBI121 consecutively to obtain the plant expression plasmid pBI-L1. The T-DNA regions of the pBI-L1 binary vector contained the constitutive Cauliflower mosaic virus (CaMV) 35S promoter and the neomycin phosphotransferase npt II gene, which allowed the selection of transformed plants using kanamycin. The tobacco plants were transformed by cocultivating them, using the leaf disc method, with Agrobacterium tumefaciens LBA4404, which harbored the plant expression plasmid. The regenerated transgenic tobacco plants were selected using kanamycin, and confirmed by PCR. The results of the Southern blot assay also showed that the HPV16 L1 gene was integrated stably into the genome of the transformed tobacco plants. The Western blot analysis showed that the transformed tobacco leaves could express the HPV16 L1 protein. Furthermore, it was demonstrated by ELISA assay that the expressed protein accounted for 0.034%-0.076% of the total soluble leaf protein, was able to form 55 nm virus-like particles compatible with HPV virus-like particle (VLP), and induced mouse erythrocyte hemagglutination in vitro. The present results indicate that the HPV16 L1 protein can be expressed in transgenic tobacco plants and the expressed protein possesses the natural features of the HPV16 L1 protein, implying that the HPV16 L1 transgenic plants can be potentially used as an edible vaccine.