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Full Bloom Stage of Prunus mume and Prunus armeniaca var. ansu - Plant Genetic Resource of ex situ Conservation in Yesan - (매실나무와 살구나무 유전자원의 만개기 특성 - 예산지역 이식의 현지외보전 식물자원 -)

  • Kang, Hee Kyoung;Song, Hong Seon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.04a
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    • pp.34-34
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    • 2018
  • 본 연구는 예산지역에서 현지외보전을 하는 매실나무(220여점) 및 살구나무(9점) 유전자원에 대한 개화 특성평가를 위하여 개화기를 지난 만개기를 연차별로 조사하였다. 대한민국에서 수집한 매실나무의 만개기는 이식 초기의 2012년에 4월 중순이었으나 이식 3년 후부터 4월 초순으로 약간 앞당겨졌다. 만개기는 2012년의 경우 모두 4월 11일 이후이었으나 2015년 이후는 4월 1~10일까지 70% 이상이었다. 연도별 보면 2015년과 2016년은 4월 1~5일에 가장 많이 만개하였고, 2017년과 2018년은 4월 6~10일에 가장 많이 만개하였다. 또한 일본에서 수집한 매실나무의 만개기도 대한민국 수집의 자원처럼 4월 초순이 대부분이었는데, 연도별로는 2015년, 2016년 및 2017년의 경우 4월 1~5일에 가장 많이 만개하였고, 2018년은 4월 6~10일에 가장 많이 만개하였다. 그러나 일본 수집의 매실나무 만개기는 3월말에서 4월 초순에 집중되어 3월 중순에서 4월 중순까지의 범위를 나타낸 대한민국 수집 자원과 약간의 차이를 보였다. 그리고 예산지역 현지외보전 살구나무(대한민국 수집)의 만개기는 2015년부터 2018년까지 모두 4월 1일부터 10일까지이었으며, 3월 및 4월 중순 이후에 만개한 꽃이 나타나지 않았다.

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A Study on the Circulation System of Biosafety Level 4 Laboratory Facilities (생물안전 4등급(BL4) 실험시설의 동선계획에 관한 연구)

  • Kwon, Soonjung;Choi, Hongbin
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.17 no.1
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    • pp.23-32
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    • 2011
  • Recently, with the advent of high risk infectious agent such as the Ebola virus, SARS, special research facilities dealing with such dangerous pathogenic are drawing attention gradually. Especially, this kind of facilities can be called BL4(Biosafety Level 4) facility. At the moment, Korean government is going to construct BL4 institute in order to handle efficiently such kind of pathogen. However, there are no proper design guidelines for BL4 facility. This paper proposes circulation system of BL4 facility on the basis of analysis of existing BL4 guidelines of Canada, and Korean BL3 facilities. The outcomes of this study are as follows. At first, functional areas of BL4 facilities have been divided into three categories according to the hazard level ; dangerous area, transitional area, and ordinary area. Secondly, circulation system of BL4 facility has been explored as a form of diagram according to the circulating subjects. These include human, laboratory animals, hazardous pathogen, equipments and cloth. This study has some limitations in that it lacks empirical evidences and concrete SOPs(Standard Operating Procedure). Despite of some weaknesses, it is expected to give some preliminary guidelines for the design of circulation system in BL4 facilities.

Studies on the Acceleration of Germination in Carrot Seed (3) Effect of some Inorganic Compounds on the Germination of Carrot Seed (당근 종자 발아 촉진에 관한 연구 (3) 당근 종자의 발아에 있어서 몇가지 무기염류의 영향)

  • 권오용
    • Journal of Plant Biology
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    • v.14 no.2
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    • pp.1-6
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    • 1971
  • When germination beds of carrot seeds were treated with either 0.01M or 0.05M concentrations of Ca(NO3)2, CaSO4, MgSO4, K2SO4 and KH2PO4, an acceleration in the germination rate was observed in the groups treated with 0.01M KH2PO4 and 0.05M MgSO4 and 0.05M Ca(NO2)3. In earlier work by the author with acetone a similar result was observed and reported. The pH range in these experiments was maintained between 5.0 and 6.0. It was found that the groups treated with 0.05M K2SO4, 0.05M Ca(NO3)2, 0.05M Ca(NO3)2, 0.05M MgSO4, 0.01M KH2PO4, 0.01M Ca(NO3)2 germinated earlier than the control group. The acceleration of the germintion rate varied with the inorganic compounds used in the following descending order; 0.01M KH2PO4, 0.05M Ca(NO3)2, 0.05M K2SO4, 0.05M CaSO4 and 0.05M KH2PO4. As a result of these expriments, it occurs to the author that in the germination of carrot seeds some inorganic compounds appear to activate the osmotic function of carrot seeds causing acceleration in the germination rate.

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Photochemical Hydrogen Evolution in K4Nb6O17 Semiconductor Particles Sensitized by Phosphonated Trisbipyridine Ruthenium Complexes

  • Jung, Young-Hee;Shim, Hyun-Kwan;Kim, Hyun-Woo;Kim, Yeong-Il
    • Bulletin of the Korean Chemical Society
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    • v.28 no.6
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    • pp.921-928
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    • 2007
  • Three different phosphonated trisbipyridine ruthenium complexes, [(4-CH3-4'-CH2PO(OH)2-2,2'-bipyridine)- (bpy)2Ru]·(PF6)2 (Ru-P1), [(4-CH3-4'-CH2PO(OH)2-2,2'-bipyridine)3Ru]·(PF6)2 (Ru-P2), and [(4,4'-CH2PO- (OH)2-2,2'-bipyridine)3Ru]·(PF6)2 (Ru-P3) were synthesized and their photochemical and electrochemical properties were studied. These ruthenium complexes were strongly adsorbed on the surface of the layered metal oxide semiconductor K4Nb6O17 that was partially acid-exchanged and sensitized up to pH 10, while the carboxylated ruthenium complex, (4,4'-COOH-2,2'-bipyridine)3Ru·Cl2 (Ru-C) that was previously studied was sensitized only below pH 4. The visible light water reduction at K4Nb6O17 that was internally platinized and sensitized by these phosphonated Ru-complexes was comparatively studied using a reversible electron donor iodide.

4th Industrial Revolution and Magnetics (1) (4차 산업혁명과 자기학(1) - 4차 산업혁명의 개황 -)

  • Kim, Hi-Jung
    • Journal of the Korean Magnetics Society
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    • v.27 no.3
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    • pp.104-113
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    • 2017
  • K. Suwab, a chairman of the World Economic Forum (WEF), reported the emerging of the $4^{th}$ industrial revolution by the convergence of artificial intelligence and robot as well as the fusion of true and virtual reality in the WEF 2016. He suggested the $4^{th}$ industrial revolution would change greatly the paradigm of industry and society in the future, and damage the security and quality of the human job severely. In this review the argument of terminology, the impacts on economics, industry technologies and jobs by the $4^{th}$ industrial revolution have been discussed. And the role of magnetics on the 2-4th industrial revolutions was reviewed briefly.

Charge/Discharge Properties of Camon Added $LiFeO_4$

  • Jin, En-Mei;Li, Hu;Jeon, Yeon-Su;Park, Kyung-Hee;Gu, Hal-Bon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.361-362
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    • 2007
  • Phospho-olivine $LiFePO_4$ cathode materials were prepared by hydrothermal reaction. Carbon black was added to enhance the electrical conductivity of $LiFePO_4$. The structural and morphological performance of $LiFePO_4$ and $LiFePO_4$-C powders were characterized by X-ray diffraction (XRD) and FE-SEM. $LiFePO_4/SPE/Li$ and $LiFePO_4$-C/SPE/Li cells were characterized electrochemically by charge/discharge experiments. The results showed that the discharge capacity of $LiFePO_4$-C/SPE/Li cell was 103 mAh/g at the first cycle. The discharge capacity of $LiFePO_4$-C/SPE/Li cell with 5 wt% carbon black was the largest among $LiFePO_4$-C/SPE/Li cells, 126 mAh/g at the first cycle and 123 mAh/g after 30 cycles, respectively. It was demonstrated that cycling performance of $LiFePO_4$-C/SPE/Li cell with 5 wt% carbon black was better than that of $LiFePO_4$/SPE/Li cell.

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Hypermethylation-mediated silencing of NDRG4 promotes pancreatic ductal adenocarcinoma by regulating mitochondrial function

  • Shi, Hao-Hong;Liu, Hai-E;Luo, Xing-Jing
    • BMB Reports
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    • v.53 no.12
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    • pp.658-663
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    • 2020
  • The N-myc downstream regulated gene (NDRG) family members are dysregulated in several tumors. Functionally, NDRGs play an important role in the malignant progression of cancer cells. However, little is known about the potential implications of NDRG4 in pancreatic ductal adenocarcinoma (PDAC). The aim of the current study was to elucidate the expression pattern of NDRG4 in PDAC and evaluate its potential cellular biological effects. Here, we firstly report that epigenetic-mediated silencing of NDRG4 promotes PDAC by regulating mitochondrial function. Data mining demonstrated that NDRG4 was significantly down-regulated in PDAC tissues and cells. PDAC patients with low NDRG4 expression showed poor prognosis. Epigenetic regulation by DNA methylation was closely associated with NDRG4 down-regulation. NDRG4 overexpression dramatically suppressed PDAC cell growth and metastasis. Further functional analysis demonstrated that up-regulated NDRG4 in SW1990 and Canpan1 cells resulted in attenuated mitochondrial function, including reduced ATP production, decreased mitochondrial membrane potential, and increased fragmented mitochondria. However, opposite results were obtained for HPNE cells with NDRG4 knockdown. These results indicate that hypermethylation-driven silencing of NDRG4 can promote PDAC by regulating mitochondrial function and that NDRG4 could be as a potential biomarker for PDAC patients.

The Reaction of Superoxide with Carbohydrate Sulphonates

  • Shin, Young-Sook;Nam Shin, Jeong E.
    • Bulletin of the Korean Chemical Society
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    • v.14 no.2
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    • pp.188-191
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    • 1993
  • The reaction between methyl 2,3-di-O-benzyl-4,6-di-O-mesyl-${\alpha}$-D-glucopyranoside (1b) and potassium superoxide resulted in hydrolysis, and gave methyl 2,3-di-O-benzyl-${\alpha}$-D-glucopyranoside (1) as a sole product. When the reaction was performed with a vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-altropyranoside (4b), again the hydrolysis product, methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4) was obtained. However, the reaction of potassium superoxide with another vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-glucopyranoside (3b), nucleophilic displacement took place to afford methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4). Apparently different results from two trans vicinal dimesylates, 3b and 4b are explained by the transient formation of epoxides, methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-allopyranoside (8) and methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-mannopyranoside (9) by $KO_2$. The reaction between the allo epoxide 8 and $KO_2$ gave altro 4. The manno epoxide 9 also afforded altro 4 as the major product. Facile epoxide formation by the reaction of a vicinal dimesylate and superoxide was also observed with 3-O-benzyl-1,2-O-isopropylidene-5,6-di-O-mesyl-${\alpha}$-D-glucofuranose: 5,6-anhydro-3-O-benzyl-1,2-O-isopropylidene-${\beta}$-L-idofuranose was obtained.

Differential Cryptanalysis of a 20-Round Reduced SMS4 Block Cipher (축소된 20-라운드 SMS4에 대한 차분 공격)

  • Kim, Tae-Hyun;Kim, Jong-Sung;Sung, Jae-Chul;Hong, Seok-Hie
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.18 no.4
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    • pp.37-44
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    • 2008
  • The 128-bit block cipher SMS4 which is used in WAPI, the Chinese WALN national standard, uses a 128-bit user key with the number of 32 rounds. In this paper, we present a differential attack on the 20-round SMS4 using 16-round differential characteristic. This attack requires $2^{126}$ chosen plaintexts with $2^{105.85}$ 20-round SMS4 decryptions. This result is better than any previously known cryptanalytic results on SMS4 in terms of the numbers of attacked rounds.

Photoluminescence properties of Mn4+-activated Li2ZnSn2O6 red phosphors

  • Choi, Byoung Su;Lee, Dong Hwa;Ryu, Jeong Ho;Cho, Hyun
    • Journal of Ceramic Processing Research
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    • v.20 no.1
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    • pp.80-83
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    • 2019
  • The Mn4+-activated Li2ZnSn2O6 (LZSO:Mn4+) red phosphors were synthesized by the solid-state reaction at temperatures of 1100-1400 ℃ in air. The synthesized LZSO:Mn4+ phosphors were confirmed to have a single hexagonal LZSO phase without the presence of any secondary phase formed by the Mn4+ addition. With near UV and blue excitation, the LZSO:Mn4+ phosphors exhibited a double band deep-red emission peaked at ~658 nm and ~673 nm due to the 2E → 4A2 transition of Mn4+ ion. PL emission intensity showed a strong dependence on the Mn4+ doping concentration and the 0.3 mol% Mn4+-doped LZSO phosphor produced the strongest PL emission intensity. Photoluminescence emission intensity was also found to be dependent on the calcination temperature and the optimal calcination temperature for the LZSO:Mn4+ phosphors was determined to be 1200 ℃. Dynamic light scattering (DLS) and field-effect scanning electron microscopy (FE-SEM) analysis revealed that the 0.3 mol% Mn4+-doped LZSO phosphor particles have an irregularly round shape and an average particle size of ~1.46 ㎛.