• Journal of the Korean Mathematical Society
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• v.57 no.3
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• pp.707-719
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• 2020

In this article we study almost contact manifolds admitting weakly Einstein metrics. We first prove that if a (2n + 1)-dimensional Sasakian manifold admits a weakly Einstein metric, then its scalar curvature s satisfies -6 ⩽ s ⩽ 6 for n = 1 and -2n(2n + 1) ${\frac{4n^2-4n+3}{4n^2-4n-1}}$ ⩽ s ⩽ 2n(2n + 1) for n ⩾ 2. Secondly, for a (2n + 1)-dimensional weakly Einstein contact metric (κ, μ)-manifold with κ < 1, we prove that it is flat or is locally isomorphic to the Lie group SU(2), SL(2), or E(1, 1) for n = 1 and that for n ⩾ 2 there are no weakly Einstein metrics on contact metric (κ, μ)-manifolds with 0 < κ < 1. For κ < 0, we get a classification of weakly Einstein contact metric (κ, μ)-manifolds. Finally, it is proved that a weakly Einstein almost cosymplectic (κ, μ)-manifold with κ < 0 is locally isomorphic to a solvable non-nilpotent Lie group.

• Journal of Korean Academy of Nursing
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• v.41 no.3
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• pp.403-410
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• 2011

Purpose: This study was to identify the current status of vaccination against the pandemic (H1N1) 2009 virus among university students from the fields of nursing and allied health from a local community and verify factors influencing vaccination. Methods: The study included 227 students in the fields of nursing and allied health from a provincial university. Data were obtained from these participants between May 31 and June 11, 2010 by using self-report questionnaires. Results: The rate of vaccination against the pandemic (H1N1) 2009 virus for these participants was 14.5%. No difference was observed in this regard between majors and school year. Factors that influence vaccination against this virus included previous vaccination against seasonal influenza and participants’ attitudes toward general vaccination. Conclusion: The results suggest that for effective pandemic (H1N1) 2009 vaccination of university students from the fields of nursing and allied health, students who have not been vaccinated should be intensively managed. Developing a vaccination program that encourages a positive attitude toward vaccination is recommended.

• Journal of Environmental Science International
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• v.11 no.1
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• pp.75-83
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• 2002

The removal performance of copper ion was studied using Na-P1 zeolites synthesized from Jeju scoria. The scoria which is found in large amounts in Jeju Island, was sampled at four regions, Jeju-shi Bonggae-dong(A). Pukcheju-gun Hanlim-eup Sangmyong-ri Mangoreum(B), Pukcheju-gun Hanlim-eup Keumag-ri(C) and Namcheju-gun Andeok-myun Dongkwang-ri(D). Synthetic Na-P1 zeolites used in this study were more effective than natural zeolite and scoria for the removal of copper ion. The removal performances of copper ion decreased in the order of Na-P1(D) > Na-P1(C) > Na-P1(B) > Na-P1(A) among Na-P1 synthesized from the scoria according to region. These results showed the same trend with cation exchange capacity(CEC) for each synthetic zeolite, i.e., the synthetic Na-P1 zeolite with a higher CEC showed a higher removal performance. The effective diffusion coefficients of copper ion by synthetic Na-P1 zeolites were one hundred and ten times higher than those by a pure zeolite 4A and the zeolite A synthesized from coal fly ash, respectively.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.90-95
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• 2016

Heat Shock 70kDa Protein 1-Like(HSPA1L)는 Heat-shock protein70(HSP70) family에 속하는 chaperone protein으로 polypeptide folding, assembly, protein degradation 등 다양한 biological processes에 관여하고 있다. HSPA1L은 human methyltransferase-like protein 21A(METTL21A)에 의해 lysine residue에 methylation이 일어나게 되는데, 암세포에서 일반적인 HSPA1L은 주로 세포질에서 발견되는 반면 methylated HSPA1L의 경우 주로 핵에서 발견이 됨으로써 HSPA1L methylation이 암 세포 성장에 중요할 역할을 할 것이라 추측되며 anti-cancer drug target으로 주목 받고 있다. 하지만 현재 HSPA1L의 구조가 부분적으로만 밝혀져 있어 HSPA1L와 METTL21A가 어떤 residue들이 interaction 하여 binding을 하는지에 대해서 아직 밝혀 지지 않았다. 이로 인해 anti-cancer drug target으로서의 연구에 제한이 있다. 이번 연구에서는 homology modeling(Galaxy-TBM, Galaxy-refine)을 통해 HSPA1L 전체 구조를 밝혀 낸 후, HSPA1L 와 METTL21A를 protein-protein docking을 통해 binding pose 예측을 하였다. 이러한 binding pose를 protein interaction analysis하여 HSPA1L과 METTL21A binding에 관여하는 중요 residue들을 밝혀 냈다. 이러한 structural information은 methylated HSPA1L와 암 세포 성장간의 연관성, 더 나아가 anti-cancer drug 개발로 까지도 이어 질 수 있을 것이라 생각한다.

• Journal of Preventive Medicine and Public Health
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• v.50 no.1
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• pp.18-28
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• 2017

Objectives: Low birth weight (LBW) is a major public health concern, especially in developing countries, and is frequently related to child morbidity and mortality. This study aimed to identify key determinants that influence the prevalence of LBW in selected developing countries. Methods: Secondary data analysis was conducted using 10 recent Demography and Health Surveys from developing countries based on the availability of the required information for the years 2010 to 2013. Associations of demographic, socioeconomic, community-based, and individual factors of the mother with LBW in infants were evaluated using multivariate logistic regression analysis. Results: The overall prevalence of LBW in the study countries was 15.9% (range, 9.0 to 35.1%). The following factors were shown to have a significant association with the risk of having an LBW infant in developing countries: maternal age of 35 to 49 years (adjusted odds ratio [aOR], 1.7; 95% confidence interval [CI], 1.2 to 3.1; p<0.01), inadequate antenatal care (ANC) (aOR, 1.7; 95% CI, 1.1 to 2.8; p<0.01), illiteracy (aOR, 1.5; 95% CI, 1.1 to 2.7; p<0.001), delayed conception (aOR, 1.8; 95% CI, 1.4 to 2.5; p<0.001), low body mass index (aOR, 1.6; 95% CI, 1.2 to 2.1; p<0.001) and being in the poorest socioeconomic stratum (aOR, 1.4; 95% CI, 1.1 to 1.8; p<0.001). Conclusions: This study demonstrated that delayed conception, advanced maternal age, and inadequate ANC visits had independent effects on the prevalence of LBW. Strategies should be implemented based on these findings with the goal of developing policy options for improving the overall maternal health status in developing countries.

• Journal of the Korean Wood Science and Technology
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• v.50 no.4
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• pp.219-236
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• 2022

Wood-based nanocomposite electrode materials were synthesized for application in supercapacitors by mixing nanostructured hematite (Fe₂O₃) with highly porous activated carbon (AC) produced from the wood-waste of Pinus roxburghii. The AC was characterized using various instrumental techniques and the results showed admirable electrochemical properties, such as high surface area and reasonable porosity. Firstly, AC was tested as an electrode material for supercapacitors and it showed a specific capacitance of 59.02 Fg^-1 at a current density of 1 Ag^-1, cycle life of 84.2% after 1,000 cycles (at a current density of 3 Ag^-1), and energy density of 5.1 Wh/kg at a power density of 135 Wkg^-1. However, when the AC was composited with different ratios of Fe₂O₃ (1:1, 2:1, and 1:2), there was an overall improvement in its electrochemical performance. Among the 3 ratios, 2:1 (AC:Fe₂O₃) had the best specific capacitance of 102.42 Fg^-1 at 1 Ag^-1, cycle life of 94.4% capacitance after 1,000 cycles (at a current density of 3 Ag^-1), and energy density of 8.34 Wh/kg at a power density of 395.15 Wkg^-1 in 6 M KOH electrolyte in a 3-electrode experimental setup with a high working voltage of 1.55 V. Furthermore, when Fe₂O₃ was doubled, 1:2 (AC:Fe₂O₃), the electrochemical capacitive performance of the electrode twisted and deteriorated due to either the accumulation of Fe₂O₃ particles within the composite or higher bulk resistance value of pure Fe₂O₃.

• Journal of Photoscience
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• v.9 no.2
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• pp.353-355
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• 2002

We prepared 3-(1-hydroxyethyl)-bacteriopyrochlorophy11-a (3) possessing magnesium atom and phytyl ester from modification of natural bacteriochlorophyll(BChl)-a. A dichloromethane solution of (3$^1$R) and (3$^1$S)-3 was diluted with 100~1000 fold volume of cyclohexane to give new species absorbing near-infrared lights. The resulting Q, maximum of (3$^1$R)-3 was 860 nm and red-shifted by 2150 $cm^{-1}$ / from the monomeric. In the nonpolar organic solvent, epimeric (3$^1$S)-3 showed a 1ess red-shifted peak at 798 nm as well as a residual monomeric band. Such visible spectra indicated that 3 diastereose1ectively aggregated in cyclohexane to afford oligomers possessing a simi1ar supramolecular structure with chlorosomal aggregates of natural BChl-d, 7,8-dehydro-form of 3.

• Preventive Nutrition and Food Science
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• v.20 no.1
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• pp.78-81
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• 2015

1,4-Dihydroxy-2-naphthoic acid (DHNA) is a bifidogenic growth stimulator (BGS) and could be a functional food ingredient since bifidobacteria are beneficial for human health. For that reason, lactic acid bacteria producing DHNA have been screened. A lactic acid bacterium LP1 strain isolated from a natural cheese was confirmed to produce DHNA, analyzed by a HPLC method. The strain was identified as Lactobacillus casei by 16S rRNA gene sequence analysis. The cell-free supernatant of fermented whey produced by L. casei LP1 presented the BGS activity for three bifidobacterial strains such as Bifidobacterium longum subsp. infantis KCTC 3127, Bifidobacterium bifidum KCTC 3202, and Bifidobacterium breve KCTC 3220 which were human-originated. To the best of our knowledge, a L. casei strain which can produce DHNA was firstly identified in this study.

• Journal of Photoscience
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• v.6 no.1
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• pp.13-19
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• 1999

Irradiation of 1-(o-allyloxyphenyl)-2-pentamethyldisilanylenthyne 2a in methanol yields two 1 : 1 photoaddition products 3 and 4 via silacyclopropene intermediate. Photolysis of 2a with acetone in deaerated methylene chloride yields site specific and regioselective 1 : 1 adducts 6 ad 7 via silacyclopropene and 1-sila-1, 2-propdiene intermediate, respectively. Photolysis of 2a and 1-(o-(3', 3'-dimethyl-2'-propenylox)phenyl)-2-pen-tamethyldisilanylethyone 2b in benzene provides novel stereoselevtive intramolecular cyclization products 10 and 11, respectively. Irradiation of 1-(o-acetoxyphenyl)-2-pentamethyldisilanyl ethyne 2c in benzene yields the photo-Fries rearrangement products 18 and 19 and a photoproduct 17 via silacyclopropene intermediate. Photolysis of 1-(o-methoxycarbonlymethoxyphenyl)-2-pentamethyl disilanylenthyne 2d in benzene provides a novel intramolecular cycloaddition product 25 and 1-(o-methoxycarbonylemthoxiyphenyl)-2-trimethylsilylethyne 26 via silacyclopropene intermediate.

• BMB Reports
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• v.47 no.5
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• pp.280-285
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• 2014

Cancer cells undergo uncontrolled proliferation, and aberrant mitochondrial alterations. Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a mitochondrial heat shock protein. TRAP1 mRNA is highly expressed in some cancer cell lines and tumor tissues. However, the effects of its overexpression on mitochondria are unclear. In this study, we assessed mitochondrial changes accompanying TRAP1 overexpression, in a mouse cell line, NIH/3T3. We found that overexpression of TRAP1 leads to a series of mitochondrial aberrations, including increase in basal ROS levels, and decrease in mitochondrial biogenesis, together with a decrease in peroxisome proliferator-activated receptor gamma coactivator-$1{\alpha}$ (PGC-$1{\alpha}$) mRNA levels. We also observed increased extracellular signal-regulated kinase (ERK) phosphorylation, and enhanced proliferation of TRAP1 overexpressing cells. This study suggests that overexpression of TRAP1 might be a critical link between mitochondrial disturbances and carcinogenesis.