Proto-Model of an Infrared Wide-Field Off-Axis Telescope

We develop a proto-model of an off-axis reflective telescope for infrared wide-field observations based on the design of Schwarzschild-Chang type telescope. With only two mirrors, this design achieves an entrance pupil diameter of 50 mm and an effective focal length of 100 mm. We can apply this design to a mid-infrared telescope with a field of view of 8 deg X 8 deg. In spite of the substantial advantages of off-axis telescopes in the infrared compared to refractive or on-axis reflective telescopes, it is known to be difficult to align the mirrors in off-axis systems because of their asymmetric structures. Off-axis mirrors of our telescope are manufactured at the Korea Basic Science Institute (KBSI). We analyze the fabricated mirror surfaces by fitting polynomial functions to the measured data. We accomplish alignment of this two-mirror off-axis system using a ray tracing method. A simple imaging test is performed to compare a pinhole image with a simulated prediction.Comment: 14 pages, 16 figure

2D perovskite stabilized phase-pure formamidinium perovskite solar cells.

Compositional engineering has been used to overcome difficulties in fabricating high-quality phase-pure formamidinium perovskite films together with its ambient instability. However, this comes alongside an undesirable increase in bandgap that sacrifices the device photocurrent. Here we report the fabrication of phase-pure formamidinium-lead tri-iodide perovskite films with excellent optoelectronic quality and stability. Incorporation of 1.67 mol% of 2D phenylethylammonium lead iodide into the precursor solution enables the formation of phase-pure formamidinium perovskite with an order of magnitude enhanced photoluminescence lifetime. The 2D perovskite spontaneously forms at grain boundaries to protect the formamidinium perovskite from moisture and suppress ion migration. A stabilized power conversion efficiency (PCE) of 20.64% (certified stabilized PCE of 19.77%) is achieved with a short-circuit current density exceeding 24 mA cm-2 and an open-circuit voltage of 1.130 V, corresponding to a loss-in-potential of 0.35 V, and significantly enhanced operational stability

Alpha-tocopherol exerts protective function against the mucotoxicity of particulate matter in amphibian and human goblet cells

Exposure to particulate matter (PM) in ambient air is known to increase the risk of cardiovascular disorders and mortality. The cytotoxicity of PM is mainly due to the abnormal increase of reactive oxygen species (ROS), which damage cellular components such as DNA, RNA, and proteins. The correlation between PM exposure and human disorders, including mortality, is based on long-term exposure. In this study we have investigated acute responses of mucus-secreting goblet cells upon exposure to PM derived from a heavy diesel engine. To this end, we employed the mucociliary epithelium of amphibian embryos and human Calu-3 cells to examine PM mucotoxicity. Our data suggest that acute exposure to PM significantly impairs mucus secretion and results in the accumulation of mucus vesicles in the cytoplasm of goblet cells. RNA-seq analysis revealed that acute responses to PM exposure significantly altered gene expression patterns; however, known regulators of mucus production and the secretory pathway were not significantly altered. Interestingly, pretreatment with alpha-tocopherol nearly recovered the hyposecretion of mucus from both amphibian and human goblet cells. We believe this study demonstrates the mucotoxicity of PM and the protective function of alpha-tocopherol on mucotoxicity caused by acute PM exposure from heavy diesel engines

A Study on the Flora of 15 Islands in the Western Sea of Jeollanamdo Province, Korea

AbstractThis study aims to investigate the flora of 15 islands in Yeonggwang, Shinan, and Mokpo of the Jeollanamdo province and the distribution of major plants in order to use the results as fundamental data for studies on plants in islands. Field surveys were performed 25 times from 2004 to 2010 to investigate the flora in these regions. A total of 793 taxa including 123 families, 421 genera, 695 species, 2 subspeices, 88 varieties, and 8 forms was found. Korean endemic plants including Hepatica insularis and Galium koreanum were 6 taxa. 25 taxa of rare plants including Trachomitum lancifolium, Daphne kiusiana, and Centranthera cochinchinensis var. lutea were confirmed 120 taxa floristic special plant species were confirmed; 11 taxa of the fifth class, four taxa of the fourth class, 28 taxa of the third class. 78 taxa of naturalized plants were confirmed

Ameliorating effects of Mango (Mangifera indica L.) fruit on plasma ethanol level in a mouse model assessed with 1H-NMR based metabolic profiling

The ameliorating effects of Mango (Mangifera indica L.) flesh and peel samples on plasma ethanol level were investigated using a mouse model. Mango fruit samples remarkably decreased mouse plasma ethanol levels and increased the activities of alcohol dehydrogenase and acetaldehyde dehydrogenase. The 1H-NMR-based metabolomic technique was employed to investigate the differences in metabolic profiles of mango fruits, and mouse plasma samples fed with mango fruit samples. The partial least squares-discriminate analysis of 1H-NMR spectral data of mouse plasma demonstrated that there were clear separations among plasma samples from mice fed with buffer, mango flesh and peel. A loading plot demonstrated that metabolites from mango fruit, such as fructose and aspartate, might stimulate alcohol degradation enzymes. This study suggests that mango flesh and peel could be used as resources for functional foods intended to decrease plasma ethanol level after ethanol uptake

Institutional Board Review for Clinical Investigations on Inflammatory Bowel Diseases: A Single-Center Study

Background/AimsThe growing volume and the diversity of clinical research has led to related laws and regulations as well as the Institutional Review Board (IRB) approval process becoming more stringent. To conduct clinical research efficiently and while following regulations, information about the IRB approval process and feedback is important for investigators. This has yet to be studied.MethodsWe included 381 gastrointestinal disease research proposals (79 with inflammatory bowel disease [IBD], and 302 with non-IBD) reviewed by the IRB of Severance Hospital between January 2009 and December 2013. We retrospectively analyzed research characteristics including research risk levels, results of initial reviews, frequencies of continuing review, numbers of IRB comments, frequencies of IRB comments, and durations from submission to approval.ResultsInvestigators' decisions on risk level were higher in the IBD group than in the non-IBD group (P<0.05). Results of initial reviews, frequencies of continuing reviews, the numbers of IRB review comments, and durations from submission to approval were not different between the two groups, but IRB decisions on risk level were higher in the IBD group (P<0.05). In subgroup analysis, the number of IRB comments from initial review on informed consent forms and procedures as well were quest of more information were significantly higher in the IBD group than in the non-IBD group (P<0.001 and 0.01, respectively).ConclusionsIn Korea, rare diseases such as IBD require more information for the IRB process due to their distinct characteristics. IBD researchers should develop research protocols more carefully and make their research as subject-friendly as possible

Three newly recorded plants of South Korea: Muhlenbergia ramosa (Hack. ex Matsum.) Makino, Dichanthelium acuminatum (Sw.) Gould & C.A. Clark and Rottboellia cochinchinensis (Lour.) Clayton

AbstractThree new Poaceae species are reported in South Korea. Muhlenbergia ramosa was found in Boryeong-si, Iksan-si, Jangsu-gun and Gwangju. Dichanthelium acuminatum and Rottboellia cochinchinensis were found in Jeonju-si, Jeollabuk-do and Seogwipo-si, Jeju-do which were thought to be alien species. Genus Dichanthelium and Rottboellia are newly reported in South Korea. Muhlenbergia ramosa was thought to be native to Korea