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The Study on Physical and Mechanical Properties of Composite Board, Using Byproduct of Plywood for Core Layer (합판 정재단 부산물을 중층 Core로 이용한 복합보드의 물리·기계적 성질에 관한 고찰)

  • Choe, Song-Kyu;Pi, Duck Won;Kang, Seog Goo
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.6
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    • pp.490-496
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    • 2013
  • The board using recycled wood waste chip tends to decrease in terms of physical and mechanical properties. The reasons are notably different shape of chips, components of used adhesive and impurity content, which bring the irregular quality and downgrading of board. More over, the board has higher emissivity of formaldehyde than regular board, because recycled chip contains adhesives that were used to make previous products. This low quality of products weakens the price and quality competitiveness, and it led to bringing the issue of problem in Korean board industry. For these reason, in this study, boards using byproducts of plywood were made to evaluate physical and mechanical properties according to manufacturing conditions. As a result, The board was consists of 4~16 mesh chips for core layer and veneer on both face and they were combined using EMDI, and its' bending strength was 57.7 $N/mm^2$ which is 215% higher than that of OSB (26.8 $N/mm^2$). Moreover, the emissivity of formaldehyde was 0.7 ppm, this board seems to substitute OSB for rated sheathing.

Synthesis of Binuclear Bismacrocyclic Iron(II) Complex by the Aerobic Oxidation of Iron(II) Complex of 1,4,8,11-Tetraazacyclotetradecane

  • Myunghyun Paik Suh;Gee-Yeon Kong;Il-Soon Kim
    • Bulletin of the Korean Chemical Society
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    • v.14 no.4
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    • pp.439-444
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    • 1993
  • The aerobic oxidation of the Fe(II) complex of 1,4,8,11-tetraazacyclotetradecane, [Fe(cyclam)$(CH_3CN)_2](ClO_4)_2$, in MeCN in the presence of a few drops of $HClO_4$ leads to low spin Fe(III) species [Fe(cyclam)$(CH_3CN)_2](ClO_4)_3$. The Fe(III) cyclam complex is further oxidized in the air in the presence of a trace of water to produce the deep green binuclear bismacrocyclic Fe(II) complex $[Fe_2(C_{20}H_{36}N_8)(CH_3CN)_4](ClO_4)_4{\cdot}2CH_3CN$. The Fe(II) ions of the complex are six-coordinated and the bismacrocyclic ligand is extensively unsaturated. $[Fe_2(C_{20}H_{36}N_8)(CH_3CN)_4](ClO_4)_4{\cdot}2CH_3CN$ crystallizes in the monoclinic space group $P2_1/n$ with a= 13.099 (1) ${\AA}$, b= 10.930 (1) ${\AA}$, c= 17.859 (1) ${\AA}$, ${\beta}$= 95.315 $(7)^{\circ}$, and Z= 2. The structure was solved by heavy atom methods and refined anisotropically to R values of R= 0.0633 and $R_w$= 0.0702 for 1819 observed reflections with F > $4{\sigma}$ (F) measured with Mo K${\alpha}$ radiation on a CAD-4 diffractometer. The two macrocyclic units are coupled through the bridgehead carbons of ${\beta}$-diimitie moieties by a double bond. The double bonds in each macrocycle unit are localized. The average bond distances of $Fe(II)-N_{imine}$, $Fe(II)-N_{amine}$, and $Fe(II)-N_{MeCN}$ are 1.890 (5), 2.001 (5), and 1.925 (6) ${\AA}$, respectively. The complex is diamagnetic, containing two low spin Fe(II) ions in the molecule. The complex shows extremely intense charge transfer band in the near infrared at 868 nm with ${\varepsilon}$= 25,000 $M^{-1}cm^{-1}$. The complex shows a one-electron oxidation wave at +0.83 volts and two one-electron reduction waves at -0.43 and-0.72 volts vs. Ag/AgCl reference electrode. The complex reacts with carbon monoxide in $MeNO_2$ to form carbonyl adducts, whose $v_{CO}$ value (2010 $cm^{-1}$) indicates the ${\pi}$-accepting property of the present bismacrocyclic ligand.

Burning Characteristics of Nitramine Propellant Embedded with Metal Wires (금속선을 삽입한 니트라민계 추진제의 연소특성)

  • 유지창
    • Journal of the Korean Society of Propulsion Engineers
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    • v.4 no.4
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    • pp.50-58
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    • 2000
  • Burning rate of the matrix propellant($r_{sb}$) and burning rate along the metal wire($r_w$) were measured and analyzed for the HTPB/AP/Al propellant embedded with Ag wire($\phi$0.15mm) according to weight % of RDX(0~20%). Variation of burning rate increment ratio($r_w$/$r_{sb}$) and pressure exponent(n) was studied for the nitramine propellant having 10% RDX embedded with three kinds of metal(Ag, Cu, and Ni-Cr) of which diameter range is between 0.1~0.6mm. Maximum burning rate increment ratio of the nitramine propellant embedded with Ag wire($\phi$0.1mm) was 5.94 at $20^{\cire}C$, 1000 psia, 16.4% faster than that of HTPB/AP propellant, it is because that autoignition temperature of the nitramine propellant was higher than that of HTPB/AP propellant. Standard deviation of absolute ($r_{wc}$/$r_{we}$)/$r_{we}$ calculated by using new empiracal equation composed of four dimensionless groups, is 6.11% less than that calculated by using original empirical equation composed of three dimensionless group. The new empiracal equation is derived from Buckingham pi theorem using the parameters such as thermal diffusivity, melting temperature. wire diameter, propellant sample diameter, frame temperature, autoignition temperature and matrix burning rate which influence on $r_w$.

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Effect of sun ginseng potentiation on epirubicin and paclitaxel-induced apoptosis in human cervical cancer cells

  • Lin, Yingjia;Jiang, Dan;Li, Yang;Han, Xinye;Yu, Di;Park, Jeong Hill;Jin, Ying-Hua
    • Journal of Ginseng Research
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    • v.39 no.1
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    • pp.22-28
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    • 2015
  • Background: Sun ginseng (SG), a specific formulation of quality-controlled red ginseng, contains approximately equal amounts of three major ginsenosides (RK1, Rg3, and Rg5), which reportedly has antitumor-promoting activities in animal models. Methods: MTT assay was used to assess whether SG can potentiate the anticancer activity of epirubicin or paclitaxel in human cervical adenocarcinoma HeLa cells, human colon cancer SW111C cells, and SW480 cells; apoptosis status was analyzed by annexin V-FITC and PI and analyzed by flow cytometry; and apoptosis pathway was studied by analysis of caspase-3, -8, and -9 activation, mitochondrial accumulation of Bax and Bak, and cytochrome c release. Results: SG remarkably enhances cancer cell death induced by epirubicin or paclitaxel in human cervical adenocarcinoma HeLa cells, human colon cancer SW111C cells, and SW480 cells. Results of the mechanism study highlighted the cooperation between SG and epirubicin or paclitaxel in activating caspase-3 and -9 but not caspase-8. Moreover, SG significantly increased the mitochondrial accumulation of both Bax and Bak triggered by epirubicin or paclitaxel as well as the subsequent release of cytochrome c in the targeted cells. Conclusion: SG significantly potentiated the anticancer activities of epirubicin and paclitaxel in a synergistic manner. These effects were associated with the increased mitochondrial accumulation of both Bax and Bak that led to an enhanced cytochrome c release, caspase-9/-3 activation, and apoptosis. Treating cancer cells by combining epirubicin and paclitaxel with SG may prove to be a novel strategy for enhancing the efficacy of the two drug types.

Effects of Soil Water Potential and Nitrogen Fertilization on Characteristics of Photosynthesis and Chlorophyll Fluorescence Induction in Schisandra chinensis Baillon

  • Seo, Young-Jin;Kim, Beung-Sung;Lee, Jong-Phil;Kim, Jong-Su;Park, Kee-Choon;Park, Chun-Geun;Ahn, Young-Sup;Cha, Seon-Woo
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.6
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    • pp.705-711
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    • 2015
  • Management of soil water and fertilization is known to primarily affect physiological properties and yield in plant. The effect of soil water potential and nitrogen application on characteristics of photosynthesis and chlorophyll fluorescence in Schisandra chinensis Baillon was investigated on a sandy loam soil. Net photosyntheis rate and transpiration rate increased as a photon flux density and was highest at -50kPa of soil water potential. Light compensation point ($1.5{\mu}molm^{-1}s^{-1}$) and dark respiration ($0.13{\mu}molCO_2m^{-1}s^{-1}$) was lowest at -50 kPa but maximum photosynthesis rate ($13.10{\mu}molCO_2m^{-1}s^{-1}$) and net apparent quantum yield ($0.083{\mu}molCO_2m^{-1}s^{-1}$) was highest at -50 kPa. As results of chlorophyll fluorescence by OJIP analysis, maximum quantum yield (Fv/Fm) of photosystem II (PSII) and PIabs was higher in treatments of -50 kPa and -60 kPa respectively, which reflects the relative reduction state of PSII. But the relative activities per reaction center such as ABS/RC and DIo/RC were low with decreasing soil water potential. Net photosyntheis rate and transpiration rate were highest at treatment of soil testing 1.0 times ($92kgha^{-1}$). Application of nitrogen resulted in high Fv/Fm, $PI_{abs}$ and low ABS/RC, DIo/RC. This result implies that -50 kPa of soil water potential and nitrogen fertilizer may improve the efficiency of photosynthesis through controlling a photosystem in Schisandra chinensis Baillon.

Study on the Validation of Sasang Digestive Function Inventory (SDFI) for Analyzing Pathophysiological Digestive Symptoms and Diagnosing Sasang Types (소화기 소증 분석과 사상체질 진단을 위한 사상소화기능검사(SDFI)의 타당화 연구)

  • Chae, Han;Lee, Jeongyun;Lee, Yong-jae
    • Journal of Sasang Constitutional Medicine
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    • v.33 no.3
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    • pp.1-15
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    • 2021
  • Introduction The clinical usefulness of Sasang Digestive Function Inventory (SDFI) for analyzing Sasang type-specific pathophysiological symptom was illustrated repeatedly. It was revised to enhance its validity, reliability and clinical usefulness, however its clinical studies supporting these were not sufficient yet. Methods 193 healthy university students responded once to Nepean Dyspepsia Index-Korean (NDIK), Functional Dyspepsia-Related Quality of Life (FDQOL), and Dutch Eating Behavior Questionnaire (DEBQ), and twice to SDFI with four weeks of interval. The Body Mass Index (BMI) and Ponderal Index (PI) were also calculated. The 4-week test-retest reliability and correlation coefficients between NDIK, FDQOL, DEBQ, and SDFI were examined using Pearson's correlation. The significant differences between Sasang types in SDFI and its subscales were examined using ANCOVA with the age as covariate. Results The range of test-retest reliability for SDFI and its subscales was from 0.801 to 0.887. The SDFI-total correlated positively with BMI (r=0.323) and DEBQ-External Eating (r=0.433), while the SDFI-Digestion negatively with NDIK (r=-0.472) and FDQOL-total (r=-0.364). The SDFI-Habit correlated positively with BMI (r=0.310) and DEBQ-total (r=0.481), and the SDFI-Appetite with DEBQ-total (r=0.322). The SDFI-total, SDFI-Digestion, and SDFI-Habit scores of Tae-Eum type (35.6±6.25, 12.38±3.24 and 9.89±3.38, respectively) were significantly bigger than those of So-Eum type (29.84±8.31, 9.93±4.28 and 7.66±3.96). Discussion The SDFI was found to be an objective clinical measure with sufficient concurrent validity for measuring eating behavior and quality of life related to overeating and dyspepsia, and illustrated distinctive differences between Sasang types. It might be useful for the effective medical education and integrative medical practice.

Effect of ciglitazone on adipogenic transdifferentiation of bovine skeletal muscle satellite cells

  • Zhang, Junfang;Li, Qiang;Yan, Yan;Sun, Bin;Wang, Ying;Tang, Lin;Wang, Enze;Yu Jia;Nogoy, Kim Margarette Corpuz;Li, Xiangzi;Choi, Seong-Ho
    • Journal of Animal Science and Technology
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    • v.63 no.4
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    • pp.934-953
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    • 2021
  • Ciglitazone is a member of the thiazolidinedione family, and specifically binds to peroxisome proliferator-activated receptor-γ (PPARγ), thereby promoting adipocyte differentiation. We hypothesized that ciglitazone as a PPARγ ligand in the absence of an adipocyte differentiation cocktail would increase adiponectin and adipogenic gene expression in bovine satellite cells (BSC). Muscle-derived BSCs were isolated from six, 18-month-old Yanbian Yellow Cattle. The BSC were cultured for 96 h in differentiation medium containing 5 µM ciglitazone (CL), 10 µM ciglitazone (CM), or 20 µM ciglitazone (CH). Control (CON) BSC were cultured only in a differentiation medium (containing 2% horse serum). The presence of myogenin, desmin, and paired box 7 (Pax7) proteins was confirmed in the BSC by immunofluorescence staining. The CL, CM, and CH treatments produced higher concentrations of triacylglycerol and lipid droplet accumulation in myotubes than those of the CON treatment. Ciglitazone treatments significantly increased the relative expression of PPARγ, CCAAT/enhancer-binding protein alpha (C/EBPα), C/EBPβ, fatty acid synthase, stearoyl-CoA desaturase, and perilipin 2. Ciglitazone treatments increased gene expression of Pax3 and Pax7 and decreased expression of myogenic differentiation-1, myogenin, myogenic regulatory factor-5, and myogenin-4 (p < 0.01). Adiponectin concentration caused by ciglitazone treatments was significantly greater than CON (p < 0.01). RNA sequencing showed that 281 differentially expressed genes (DEGs) were found in the treatments of ciglitazone. DEGs gene ontology (GO) analysis showed that the top 10 GO enrichment significantly changed the biological processes such as protein trimerization, negative regulation of cell proliferation, adipocytes differentiation, and cellular response to external stimulus. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that DEGs were involved in the p53 signaling pathway, PPAR signaling pathway, biosynthesis of amino acids, tumor necrosis factor signaling pathway, non-alcoholic fatty liver disease, PI3K-Akt signaling pathway, and Wnt signaling pathway. These results indicate that ciglitazone acts as PPARγ agonist, effectively increases the adiponectin concentration and adipogenic gene expression, and stimulates the conversion of BSC to adipocyte-like cells in the absence of adipocyte differentiation cocktail.

Study of Anti-inflammatory Activity of 7 Herbal Prescription Effective for Sleep Disorders and Atopic Dermatitis (수면 장애 및 아토피피부염에 효과적인 7 가지 한약 처방의 항염증 활성 연구)

  • Choi, Min-Jin;Nguyen, Ly Thi Huong;Jeong, Jeonghwa;Park, Minyoung;Yoon, Joohee;Lee, Byung-Wook;Yang, In-Jun;Shin, Heung-Mook
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.35 no.2
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    • pp.56-63
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    • 2021
  • This study was conducted to find a candidate prescription with anti-inflammatory efficacy of 7 herbal prescriptions known to be effective in atopic dermatitis and sleep disorders in Korean medicine. The anti-inflammatory of the 7 herbal prescriptions extracts were evaluated by ELISA assay and Western blot assay. 7 herbal prescriptions, Seongyutang(SU), Danseontoetang(DST), Sotosajahwan(ST), Jisiljagyagsan(JJ), Seokchangpo(SCP), Wiryeongseon(WLS), Gogojohwan(GGJ) 30 % EtoH extract was used for in vitro experiments. In TNF-α + IFN-γ(TI) stimulated HaCaT cells, all 7 herbal prescriptions reduced TARC and MDC production, and JJ strongly reduced TARC and MDC production at 100 ㎍/ml concentration. SCP strongly reduced MDC production at 10 ㎍/ml and 100 ㎍/ml concentration. In addition, in substance P(SP)/CRH stimulated HMC-1 cells, JJ strongly inhibited VEGF production at both 10 and 100 ㎍/ml concentrations. In LPS/CRH stimulated Raw264.7 cells, all 7 herbal prescriptions significantly inhibited TNF-α. PMA + Ionomycin(PI)/CRH stimulated EL4 cells, SU significantly reduced IL-4 production at both concentrations of 10 and 100 ㎍/ml. WLS significantly reduced IL-17 production at both concentrations of 10 and 100㎍/ml. This suggests that 7 herbal prescriptions have anti-inflammatory effects by reducing inflammatory cytokines in keratinocytes, mast cells and macrophages caused by inflammation. Therefore, it is expected that 7 herbal prescriptions that are effective for sleep disorders and atopic dermatitis can be used as therapeutic materials for sleep disorders and diseases associated with atopic dermatitis.

The Relationship of Country Image, Product-Country Image, and Purchase Intention of Korean Products: Focusing on Differences among Ethnic Groups in South Africa

  • Lee, You-Kyung;Robb, Charles Arthur
    • Journal of Korea Trade
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    • v.23 no.6
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    • pp.33-51
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    • 2019
  • Purpose - The purpose of this study is to provide practical implications for Korean companies searching for new market opportunities. From the experimental analysis, the impact of country image on product-country image and purchase intention of Korean products are measured. In addition, this study disaggregates the impacts of country image and product-country image and purchase intention among ethnic groups in South Africa for searching further useful implications. Design/methodology - To examine South African consumers' country image and product-country image towards Korean products, data were collected between June and July 2019 through an online questionnaire, and 335 questionnaires were used for analysis. Firstly, the multivariate analysis was conducted to examine the general tendency of South African consumers' perceptions of country image to Korea, product-country image, and purchase intention among three ethnic group consumers. Then in order to verify the country image model and hypotheses of the study, we analyzed the structural models for each of the three ethnic groups and compared the sizes of the path coefficients for each groups. To compare the difference of path coefficients across ethnic groups, configural invariance, metric invariance, and scalar invariance tests were conducted sequentially. Findings - In the black and white ethnic groups, the country image had a statistically significant impact on product-country image, but it did not affect the purchase intention to Korean products. The product-country image showed a statistically significant impact on the purchase intention to Korean products in both ethnic group. However, in the coloured ethnic group consumer, the country image had a significant effect on the product-country image, but it did not affect the purchase intention of Korean products. In addition, the product-country image did not have a significant influence on the purchase intention of coloured ethnic group consumers unlike black and white ethnic group consumers. The results of this study suggest that even though differences in terms of the impact of CoI on PCI and PI were investigated for the sample of white, coloured, and black respondents, the groups seemed to respond in a reasonably comparable manner. Originality/value - South Africa occupies more than 20% of Africa's total GDP in sub-Saharan Africa and is a hub for Southern African logistics as a hub for Korean companies to enter Africa. However, it is rare to find a study focused on the determinants of consumer behavior in South Africa. In particular, this study disaggregates the impacts of country image and product-country image on consumer behavior across ethnic groups in South Africa. Therefore, this study could provide practical implications for Korean firms which desire to diversify their export markets and pioneer future markets.

Effects of Auricular Acupressure on Quality of Sleep and Depression (귀 지압이 수면의 질과 우울증에 미치는 영향)

  • Shin, Hye-Yeon;Jang, Yun-Jeong;Choe, Cheong-Hun;Lee, Da-Hea;Lee, Eun Jin
    • Journal of the Korea Convergence Society
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    • v.12 no.12
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    • pp.509-518
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    • 2021
  • This study was conducted to examine the effects of auricular acupressure on quality of sleep and depression. Adults who had insomnia for over 1 month were recruited. Participants were distributed randomly to the experimental group(n=22) and the control group(n=22). The experimental group received auricular acupressure on Shen men(TF2), insomnia 1(SF4), insomnia 2(SF1), and anti-depression(LO8) for 1 week. The contrast group received sleep hygiene education. The mean differences of the quality of sleep were 4.05±2.52 in the experimental group and 1.45±3.77 in the control group. Auricular acupressure significantly decreased insomnia in the experimental group compared to the control group(t=3.07, p=.004). Depression scores after acupressure were not different between the experimental group and the control group. After controlling the religion as a covariate, the mean difference of depression in the experimental group was higher than the control group(F=4.22, p=.046). In conclusion, auricular acupressure decreased insomnia and depression. Therefore, further studies on different acupressure points such as shen men, jiao gan, heart, pi zhi xia, and endocrine are recommended.