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Park S.-H.,Gyeonggi Science High School for the Gifted | Jung M.-H.,Sogang University | Lee Y.-J.,Dankook University | Huh Y.-D.,Dankook University
Dalton Transactions | Year: 2017

We present a confined condensation technique for the fabrication of layered copper hydroxide frameworks from lamellar copper-organic assemblies with long alkyl chains through the selective introduction of hydroxo bridging ligands. The complete transformations of two different lamellar copper-organic assemblies, Cu(C12H25SO4)2·4H2O (Cu-DS) and Cu2(C11H23CO2)4·2H2O (Cu-lau), into the corresponding layered copper hydroxide frameworks, Cu2(OH)3(C12H25SO4) (Cu-OH-DS) and Cu2(OH)1.8(C11H23CO2)2.2 (Cu-OH-lau), were achieved via confined condensation. The magnetic properties of both lamellar copper-organic assemblies, Cu-DS and Cu-lau, and both layered copper hydroxide frameworks, Cu-OH-DS and Cu-OH-lau, were investigated. It was found that drastic changes in the magnetic properties arise as a result of the confined condensation process. © The Royal Society of Chemistry.


Chung I.,Kyung Hee University | Lee J.,Kyung Hee University | Park Y.S.,Kyung Hee University | Lim Y.,Eunkwang Girl's High School | And 3 more authors.
Journal of Ginseng Research | Year: 2015

Background: UV-irradiated keratinocytes secrete various proinflammatory cytokines. UV-induced skin damage is mediated by growth factors and proinflammatory cytokines such as granulocyte macrophage colony stimulating factor (GM-CSF). In a previous study, we found that the saponin of Korean Red Ginseng (SKRG) decreased the expression of GM-CSF in UVB-irradiated SP-1 keratinocytes. In this study, we attempted to find the inhibitory mechanism of SKRG on UVB-induced GM-CSF expression in SP-1 keratinocytes. Methods: We investigated the inhibitory mechanism of SKRG and ginsenosides from Panax ginseng on UVB-induced GM-CSF expression in SP-1 keratinocytes. Results: Treatment with SKRG decreased the expression of GM-CSF mRNA and protein induced by irradiation of UVB in SP-1 keratinocytes. The phosphorylation of ERK was induced by UVB at 10 min, and decreased with SKRG treatment in SP-1 keratinocytes. In addition, treatment with SKRG inhibited the UVB-induced phosphorylation of epidermal growth factor receptor (EGFR), which is known to be an upstream signal of ERK. From these results, we found that the inhibition of GM-CSF expression by SKRG was derived from the decreased phosphorylation of EGFR. To identify the specific compound composing SKRG, we tested fifteen kinds of ginsenosides. Among these compounds, ginsenoside-Rh3 decreased the expression of GM-CSF protein and mRNA in SP-1 keratinocytes. Conclusion: Taken together, we found that treatment with SKRG decreased the phosphorylation of EGFR and ERK in UVB-irradiated SP-1 keratinocytes and subsequently inhibited the expression of GM-CSF. Furthermore, we identified ginsenoside-Rh3 as the active saponin in Korean Red Ginseng. © 2015, The Korean Society of Ginseng, Published by Elsevier. All rights reserved.


PubMed | Gyeonggi Science High School for the Gifted, Eunkwang Girls High School and Kyung Hee University
Type: Journal Article | Journal: Journal of ginseng research | Year: 2016

UV-irradiated keratinocytes secrete various proinflammatory cytokines. UV-induced skin damage is mediated by growth factors and proinflammatory cytokines such as granulocyte macrophage colony stimulating factor (GM-CSF). In a previous study, we found that the saponin of Korean Red Ginseng (SKRG) decreased the expression of GM-CSF in UVB-irradiated SP-1 keratinocytes. In this study, we attempted to find the inhibitory mechanism of SKRG on UVB-induced GM-CSF expression in SP-1 keratinocytes.We investigated the inhibitory mechanism of SKRG and ginsenosides from Panax ginseng on UVB-induced GM-CSF expression in SP-1 keratinocytes.Treatment with SKRG decreased the expression of GM-CSF mRNA and protein induced by irradiation of UVB in SP-1 keratinocytes. The phosphorylation of ERK was induced by UVB at 10min, and decreased with SKRG treatment in SP-1 keratinocytes. In addition, treatment with SKRG inhibited the UVB-induced phosphorylation of epidermal growth factor receptor (EGFR), which is known to be an upstream signal of ERK. From these results, we found that the inhibition of GM-CSF expression by SKRG was derived from the decreased phosphorylation of EGFR. To identify the specific compound composing SKRG, we tested fifteen kinds of ginsenosides. Among these compounds, ginsenoside-Rh3 decreased the expression of GM-CSF protein and mRNA in SP-1 keratinocytes.Taken together, we found that treatment with SKRG decreased the phosphorylation of EGFR and ERK in UVB-irradiated SP-1 keratinocytes and subsequently inhibited the expression of GM-CSF. Furthermore, we identified ginsenoside-Rh3 as the active saponin in Korean Red Ginseng.


Heo G.,Gyeonggi Science High School for the Gifted | Choi S.,Gyeonggi Science High School for the Gifted | Lee K.H.,Gyeonggi Science High School for the Gifted | Koo N.,Sungkyunkwan University | Kwon S.,Sungkyunkwan University
Electronics Letters | Year: 2014

A cube root algorithm in Fq proposed by Pocklington and later rediscovered by Padró and Sáez is clarified and generalised. Some errors in the result of Padró and Sáez are corrected and a full generalisation of their result is given. A comparison of the implementation of the proposed algorithm with the two most popular cube root algorithms is also given, namely the Adleman-Manders-Miller algorithm and the Cipolla-Lehmer algorithm. To the authors' knowledge, this comparison is the first one which compares three fundamental algorithms together. © The Institution of Engineering and Technology 2014.


Woo J.-H.,Seoul National University | Kim J.-G.,Seoul National University | Park D.,University of California at Irvine | Bae H.-J.,Yonsei University | And 4 more authors.
Journal of the Korean Astronomical Society | Year: 2014

We search for misclassified type 1 AGNs among type 2 AGNs identified with emission line flux ratios, and investigate the properties of the sample. Using 4 113 local type 2 AGNs at 0.02 < z < 0.05 selected from Sloan Digital Sky Survey Data Release 7, we detected a broad component of the Hα line with a Full-Width at Half-Maximum (FWHM) ranging from 1 700 to 19 090 km s-1 for 142 objects, based on the spectral decomposition and visual inspection. The fraction of the misclassified type 1 AGNs among type 2 AGN sample is ∼3.5%, implying that a large number of missing type 1 AGN population may exist. The misclassified type 1 AGNs have relatively low luminosity with a mean broad Hα luminosity, log LHα = 40.50 ± 0.35 erg s-1, while black hole mass of the sample is comparable to that of the local black hole population, with a mean black hole mass, log MBH = 6.94 ± 0.51 M⊙. The mean Eddington ratio of the sample is log Lbolbol/LEdd = -2.00± 0.40, indicating that black hole activity is relatively weak, hence, AGN continuum is too weak to change the host galaxy color. We find that the O III lines show significant velocity offsets, presumably due to outflows in the narrow-line region, while the velocity offset of the narrow component of the Hα line is not prominent, consistent with the ionized gas kinematics of general type 1 AGN population. © 2014. The Korean Astronomical Society. All rights reserved.


Oh I.-H.,Korea Atomic Energy Research Institute | Kim J.Y.,Seoul Science High School for the Gifted Stud. | Park S.-H.,Gyeonggi Science High School for the Gifted
Zeitschrift fur Kristallographie - New Crystal Structures | Year: 2016

C28H40MnN6O12S2, monoclinic, P21/c (no. 14), a = 6.211(5) Å, b = 7.146(5) Å, c = 38.895(5) Å, β = 91.283(5)°, V = 1725.9(19) Å3, Z = 2, Rgt(F) = 0.0639, wRref(F2) = 0.1094, T = 300 K. © 2016 In-Hwan Oh et al., published by De Gruyter.


Lee J.,Gyeonggi Science High School for the Gifted | Park S.,Gyeonggi Science High School for the Gifted | Jeong J.Y.,Chungbuk National University | Jo Y.H.,Chungbuk National University | Lee M.K.,Chungbuk National University
Natural Product Sciences | Year: 2015

Hesperidin, which is the most abundant flavonoid of Citrus unshiu (Rutaceae), has been reported to possess diverse activities and widely used as functional foods and cosmetics. For the development of functional products, extraction procedure is indispensable. Extraction conditions affect the composition of extract as well as its biological activity. Therefore, we tried to optimize extraction conditions such as extraction solvent, extraction time and extraction temperature for maximum yield of hesperidin using response surface methodology with threelevel-three-factor Box-Behnken design (BBD). Regression analysis showed a good fit of the experimental data and the optimal condition was obtained as ethanol concentration, 59.0%; temperature 71.5 ºC and extraction time, 12.4 h. The hesperidin yield under the optimal condition was found to be 287.8 µg per 5 mg extract, which was well matched with the predicted value of 290.5 µg. These results provides optimized extraction condition for hesperidin and might be useful for the development of hesperidin as functional products like health supplements, cosmetics and medicinal products. © 2015, Korean Society of Pharmacognosy. All rights reserved.


Lee E.S.,Gyeonggi Science High School for the Gifted | Lee M.K.,Chungbuk National University
Natural Product Sciences | Year: 2013

Caffeine and epigallocatechin gallate (EGCG) are major constituents of green tea, the leaves of Camellia sinensis (Theaceae). Although EGCG is well known for diverse beneficial effect, caffeine is sometimes harmful with adverse effects. Therefore, the extraction efficiency was investigated using different extraction method such as extraction solvent, extraction time, extraction method, and repeated extraction. The content of EGCG and caffeine in green tea extract was quantitated by HPLC analysis. The extraction condition exerted difference on the extraction yield. The content of EGCG was also affected by different extraction condition. Especially, the extraction solvent greatly affected the content of EGCG in the extract. However, the content of caffeine was less affected compared to that of EGCG. The inhibitory effect of green tea extract on pancreatic lipase was almost similar regardless of extraction condition. Taken together, optimization of extraction condition will provide best efficacy for further development of green tea as anti-obesity therapeutics.


Lee J.,Gyeonggi Science High School for The Gifted | Lee J.,Korea National University of Education
Mycobiology | Year: 2011

Nuclear distribution within the extra-radical fungal structures and during spore production in the arbuscular mycorrhizae fungus Glomus intraradices was examined using an in vitro monoxenic culture system. A di-compartmental monoxenic culture system was modified using a nitrocellulose membrane and a coverglass slip for detailed observations. Nuclear distribution was observed using the fluorescent DNA binding probes SYBR Green I and DAPI. Both septate and non-septate mycelial regions were observed, but cytoplasmic contents were only found within non-septate mycelia. Nuclear fluorescent staining revealed that the non-septate hyphal region contained nuclei only with cytoplasm, and that nuclear distribution was limited by septa. Swollen hyphal bodies were often associated with septate and empty-looking hyphae. Cytoplasmic contents filled the swollen hyphal body from the non-septate hyphal region following removal of the septa. As a consequence, the swollen body developed into a new spore. These observations provide understanding about the distribution of AM fungal nuclei within extra-radical mycelia and during spore formation. The results suggest a mechanism by which the development of a cytoplasm-containing mycelium is controlled by the formation or removal of septa to efficiently maintain and proliferate essential contents. This mechanism may provide a survival strategy to the fungus. © The Korean Society of Mycology.


Roh H.G.,Gyeonggi Science High School for the Gifted | Kim S.G.,Gyeonggi Science High School for the Gifted | Jung J.,Kyonggi University
Korean Journal of Chemical Engineering | Year: 2014

Removal of toxic heavy metal ions from environmental and biological systems is important, but the use of commercially available heavy metal adsorbents is complicated by the need for specific pretreatment steps. We chose to study human hair treated with perm lotion as a heavy metal adsorbent because it is readily available and contains a large number of sulfur atoms for strong coordination to heavy metal ions. The optimal pH of adsorption by perm lotion-treated human hair was 4.16, which was slightly higher than the isoelectric point (pI) of the hair. The maximum removal ratio at pH 4.16 was 88.5% for a 50 ppm Cu2+ solution, and 96.79% for a 50 ppm Pb2+ solution. Almost 90% of the Pb2+ was removed from a 120 ppm Pb2+ solution. The perm-lotion-treated human hair was a cation-selective adsorbent. © 2013 Korean Institute of Chemical Engineers, Seoul, Korea.

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