• Journal of the Korean Ceramic Society
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• v.31 no.11
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• pp.1283-1292
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• 1994

Ultra-fine $\beta$-SiC powders were fabricated by self-propagating high temperature synthesis process (SHS) using chemical furnace. The dependences of the C powders with different surface areas, the molar ratios of C/Si, the weight ratios of chemical fuel content, and pellet diameter-size on synthesis were investigated. Compositional and structural characterization of these powders was carried out by scanning electron micrograph and X-ray diffraction. The $\beta$-SiC powders which had C/Si mole ratio=1.05, 3 times chemical fuel contents, and pellet diameter=20 mm were optimum for synthesis efficiency. By optimizing process-variables, it is possible to fabricate $\beta$-SiC powders which have little secondary phases ($\alpha$-SiC).

• Tuberculosis and Respiratory Diseases
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• v.40 no.2
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• pp.147-152
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• 1993

Background: There is evidence that platelet is activated in chronic obstructive pulmonary disease and activated platelet with injured endothelium contribute to the pathogenesis of pulmonary hypertension, prognostic factor of chronic obstructive pulmonary disease. So, we have investigated platelet function further in chronic obstructive pulmonary disease and effect of platelet activation on pulmonary hypertension. Method: We studied platelet aggregation ratio and alpha-granule products such as platelet factor 4(PF4) and beta-thromboglobulin (${\beta}$-TG) in control subjects and COPD without and with pulmonary hypertension subjects. Result: 1) The platelet aggregation ratio (PAR) was $0.99{\pm}0.04$ in control subjects, $0.98{\pm}0.05$ in COPD without pulmonary hypertension subjects and $0.89{\pm}0.08$ in COPD with pulmonary hypertension subjects. The platelet aggregation ratio of COPD subjects was tend to decrease than that of control subjects and the ratio of COPD with pulmonary hypertension subjects was significantly lower than that of control subjects. 2) The platelet factor 4 (PF4, IU/ml) was $4.7{\pm}1.2$ in control subjects, $18.6{\pm}4.9$ in COPD without pulmonary hypertension subjects and $57.2{\pm}12.7$ in COPD with pulmonary hypertension subjects. The level of COPD subjects was significantly higher than that of control subjects and the level of COPD with pulmonary hypertension subjects was significantly higher than that of COPD without pulmonary hypertension subjects. 3) The beta-thromboglobulin (${\beta}$-TG, IU/ml) was $34.4{\pm}5.8$ in control subjects, $80.4{\pm}18.1$ in COPD without pulmonary hypertension subjects and $93.0{\pm}14.0$ in COPD with pulmonary hypertension subjects. The level of COPD subjects was significantly higher than that of conrtrol subjects and the level of COPD with pulmonary hypertension subjects was tend to increase than that of COPD without pulmonary hypertension subjects. 4) There was no correlation between the clinical parameters and PAR, PF4 and ${\beta}$-TG but there was significant correlation among PAR, PF4 and ${\beta}$-TG. Conclusion: The platelet is activated in chronic obstructive pulmonary disease and the platelet of COPD with pulmonary hypertension is tend to be activated more than that of COPD without pulmonary hypertension. So, activated platelet may involve in the pathogenesis and maintenance of pulmonary hypertension in COPD subjects and modulation of platelet activity that might reduce pulmonary hypertension needs to be determined.

• Journal of the Korean Applied Science and Technology
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• v.16 no.1
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• pp.83-94
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• 1999

Glycoside fatty acid esters were synthesized by lipase-catalyzed glycosylation of fatty acids with methyl glycoside in solvent and solvent free process. Optimum condition of solvent process using 2-methyl-2-propanol were : moral ratio of methyl glycoside to fatty acid 1:3: initial concentration of methyl glycoside 50g/l:enzyme(immodilized lipase Novozym 435 from Candidia antarctica) content 1%(w/v) : desiccant content 9%(w/v); reaction temperature $60^{\circ}C$: reaction time 10hrs. The yield of 99% was obtained. Solvent-free process was carried out in total absence of solvent at $70^{\circ}C$ under reduced pressure, 5-20mmHg. To give meximum yield of 99% at the optimum condition of molar ratio of methyl glycoside to fatty acid 1:3, enzyme content 10%(w/w), and reaction time 10hrs. The glycosylation reactivity of different glycosylation agents were sequent to $Methyl-{\beta}-D-fructofuranoside$. $Methyl-{\beta}-D-glucopyranoside$. $Methyl-{\beta}-D-fructofuranosi$ de, and $Methyl-{\alpha}-D-glucopyranoside$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.427-431
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• 1984

This experiment was conducted to study the effects of Korean ginseng and tocopherol on serum testosterone level, protein metabolism and swimming endurance in rats. Powdered ginseng (2.5 g/kg) and ${\alpha}-tocopherol$ (250 mg/kg) were added directly into the basal diet of rats feeding for 6 weeks. The serum testosterone level of ginseng-treated rats had no difference from that of control rats, but the level was slightly increased in tocopherol-treated rats. In the case of ginseng-treated rats, there were no significant difference in the contents of albumin, ${\alpha}_1-globulin$, ${\alpha}_2-globulin$, ${\gamma}-globulin$ and A/G ratio compared with those of the control rats, however, the levels of total protein and ${\beta}-globulin$ were increased significantly(p<0.005). Total protein value of tocopherol-treated rats was higher than that of the control rats(p<0.005). In contrast, albumin content was slightly decreased. The contents of ${\alpha}_1-globulin$, ${\alpha}_2-globulin$, ${\beta}-globuiln$ and ${\gamma}-globulin$ were higher in the rats fed tocopherol diet that those obtained from the control rats. Accordingly A/G value was markedly decreased (p<0.001). In swimming endurance test, both Korean ginseng and ${\alpha}-tocopherol$ did not appear to have any effect on rats' stamina.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1086-1091
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• 1999

$K^+-{\beta}/{\beta}"-Al_2O_3$ in the ternary system $K_2O-MgO-Al_2O_3$ was directly synthesized by solid state reaction. The phase formation and phase relation were carefully investigated in relation to starting composition, calcining temperature and time, and dispersion medium. The optimal synthetic condition was also examined for the formation of ${\beta}"-Al_2O_3$ phase with a maximum fraction. As a composition range, the mole ratio of $K_2O$ to $Al_2O_3$ was changed from 1:5 to 1:6.2 and the amount of MgO used as a stabilizer was varied from 4.2 wt % to 6.3 wt %. The calcining temperature was selected between $1000^{\circ}C$ and $1500^{\circ}C$. At $1000^{\circ}C$, the ${\beta}/{\beta}"-Al_2O_3$ phases began to form resulted from the combining of ${\alpha}-Al_2O_3$ and $KAlO_2$ and increased with temperature rising. All of ${\alpha}-Al_2O_3$ phase disappeared to be homogenized to the ${\beta}/{\beta}"-Al_2O_3$ phase at $1200^{\circ}C$. Near the temperature at $1300^{\circ}C$, the fraction of ${\beta}"-Al_2O_3$ phase showed a maximum value with the composition of $K_{1.67}Mg_{0.67}Al_{10.33}O_{17}$. At temperatures above $1300^{\circ}C$, the fraction of ${\beta}"-Al_2O_3$ phase decreased gradually owing to $K_2O$ loss caused by a high potassium vapor pressure, and the appropriate calcining time was about 5 hours. Acetone was more effective than distilled water as a dispersion medium for milling and mixing.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.127-132
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• 2007

[ ${\alpha},\;{\alpha}$ ]-Trehalose was efficiently modified by a transgalactosylation reaction of Escherichia coli ${\beta}-galactosidase$ using lactose as a donor to yield two galactosyl trehalose trisaccharides. The reaction products of trehalose by the enzyme were observed by thin layer chromatography (TLC) and high performance anion exchange chromatography (HPAEC) and were purified by BioGel P2 gel permeation chromatography and recycling preparative HPLC. Liquid chromatography-mass spectrometry (LC-MS) and ^{13}C$ nuclear magnetic resonance (NMR) analyses revealed that the structures of the main products were $6^2-{\beta}-D-galactosyl$ trehalose (1) and $4^2-{\beta}-D-galactosyl$ trehalose (2). A reaction of 30%(w/v) trehalose and 15%(w/v) lactose at pH 7.5 and $45^{\circ}C$ resulted in a total yield of approximately 27-30% based on the amount of trehalose used. The galactosyl trehalose products were not hydrolyzed by trehalose. In addition the mixture of transfer products (9:1 ratio of 1 to 2) showed higher thermal stability than glucose, lactose, and maltose, but less than trehalose, against heat treatment over $100^{\circ}C$ at pH 4 and 7. It also exhibited better thermal stability than sucrose at pH 4 alone.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.35-39
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• 2010

Soybean proteins are widely used for human and animal feed in the world. ${\beta}$-conglycinin protein exhibits poor nutritional and food processing properties and Kunitz trypsin inhibitor (KTI) protein is a main anti-nutritional factor in soybean seed. The objective of this research was to identify the inheritance of $cgy_1$ gene and ti gene for the improvement of soybean cultivar with no KTI proteins and low amount of ${\beta}$-conglycinin. $F_2$ population was made by crossing between "Gaechuck2ho" (${\alpha}^{\prime}$-subunit present $Cgy_1Cgy_1$, KTI protein absent titi) and PI506876 (${\alpha}^{\prime}$-subunit absent $cgy_1cgy_1$, KTI protein present TiTi) parent. A total of 434 $F_2$ seeds were obtained and analyzed for the segregation of ${\alpha}^{\prime}$-subunit protein and KTI protein using SDS-PAGE. The segregation ratio of 3 : 1 for $Cgy_1$ locus (310 $Cgy_1$_ : 124 $cgy_1cgy_1$) and Ti locus (339 Ti_ : 95 titi) were observed. Segregation ratios of 9 : 3 : 3 : 1 (241 $Cgy_1$_Ti_: 69 $Cgy_1$_titi: 98 $cgy_1cgy_1$Ti_: 26 $cgy_1cgy_1titi$) between $Cgy_1$ gene and Ti gene in $F_2$ seeds were also observed (${\chi}^2= 5.367$, P = 0.10 - 0.20). This data showed that $Cgy_1$ gene was inherited independently with the Ti gene in soybean. These results will be useful in breeding program for selecting the line that does not exhibit or lacks both ${\alpha}^{\prime}$-subunit protein and KTI protein in soybean.

• Smart Structures and Systems
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• v.19 no.3
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• pp.309-322
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• 2017

In this paper, the buckling, and free vibration analysis of tapered functionally graded carbon nanotube reinforced composite (FG-CNTRC) micro Reddy beam under longitudinal magnetic field using finite element method (FEM) is investigated. It is noted that the material properties of matrix is considered as Poly methyl methacrylate (PMMA). Using Hamilton's principle, the governing equations of motion are derived by applying a modified strain gradient theory and the rule of mixture approach for micro-composite beam. Micro-composite beam are subjected to longitudinal magnetic field. Then, using the FEM, the critical buckling load, and natural frequency of micro-composite Reddy beam is solved. Also, the influences of various parameters including ${\alpha}$ and ${\beta}$ (the constant coefficients to control the thickness), three material length scale parameters, aspect ratio, different boundary conditions, and various distributions of CNT such as uniform distribution (UD), unsymmetrical functionally graded distribution of CNT (USFG) and symmetrically linear distribution of CNT (SFG) on the critical buckling load and non-dimensional natural frequency are obtained. It can be seen that the non-dimensional natural frequency and critical buckling load decreases with increasing of ${\beta}$ for UD, USFG and SFG micro-composite beam and vice versa for ${\alpha}$. Also, it is shown that at the specified value of ${\alpha}$ and ${\beta}$, the dimensionless natural frequency and critical buckling load for SGT beam is more than for the other state. Moreover, it can be observed from the results that employing magnetic field in longitudinal direction of the micro-composite beam increases the natural frequency and critical buckling load. On the other hands, by increasing the imposed magnetic field significantly increases the stability of the system that can behave as an actuator.

• IMMUNE NETWORK
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• v.15 no.3
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• pp.142-149
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• 2015

Lung fibrosis is a life-threatening disease caused by overt or insidious inflammatory responses. However, the mechanism of tissue injury-induced inflammation and subsequent fibrogenesis remains unclear. Recently, we and other groups reported that Th17 responses play a role in amplification of the inflammatory phase in a murine model induced by bleomycin (BLM). Osteopontin (OPN) is a cytokine and extracellular-matrix-associated signaling molecule. However, whether tissue injury causes inflammation and consequent fibrosis through OPN should be determined. In this study, we observed that BLM-induced lung inflammation and subsequent fibrosis was ameliorated in OPNdeficient mice. OPN was expressed ubiquitously in the lung parenchymal and bone-marrow-derived components and OPN from both components contributed to pathogenesis following BLM intratracheal instillation. Th17 differentiation of $CD4^+$ ${\alpha}{\beta}$ T cells and IL-17-producing ${\gamma}{\delta}$ T cells was significantly reduced in OPN-deficient mice compared to WT mice. In addition, Th1 differentiation of $CD4^+$ ${\alpha}{\beta}$ T cells and the percentage of IFN-$\gamma$-producing ${\gamma}{\delta}$ T cells increased. T helper cell differentiation in vitro revealed that OPN was preferentially upregulated in $CD4^+$ T cells under Th17 differentiation conditions. OPN expressed in both parenchymal and bone marrow cell components and contributed to BLM-induced lung inflammation and fibrosis by affecting the ratio of pathogenic IL-17/protective IFN-$\gamma$ T cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1612-1619
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• 2006

This Study was designed to investigate the mechanism of Mixture of Bambusae Caulis in Liquamen and Bamboo Extract on the change of regional cerebral blood flow (rCBF) and blood pressure (BP) in normal rats, and further to investigate cytokines production in serum of cerebral ischemic rats. Mixture were as follows ; Bamboo Extract extracted with distilled water at 98 $^{\circ}C$ for 3 hrs, Mixture of Bambusae Caulis in Liquamen and bamboo Extracts (MLE) mixed at the ratio 1 to 100 (MLE100), 1 to 50 (MLE50), 1 to 20 (MLE20), 1 to 10 (MLE10), 1 to 5 (MLE5). The results were as follows ; The MLE-induced increase in rCBF was significantly inhibited by pretreatment with indomethacin (1 mg/kg, I.p.), an inhibitor of cyclooxygenase as well as methylene blue (10 $^{\mu}g/kg$, I.p.), an inhibitor of guanylate cyclase. The MLE-induced increase in BP was significantly inhibited by pretreatment with methylene blue. In cytokines production in the serum drawn from femoral arterial 1 hr after middle cerebral artery occlusion, MLE5 significantly increased production of TGF-${\beta}$ and increased production of IL-10, but significantly decreased production of TGF-${\alpha}$ compared with control group. In cytokines production in the serum drawn from femoral arterial 1 hr after reperfusion, MLE5 significantly increased production of TGF-${\beta}$ and IL-10, but significantly decreased production of TGF-${\alpha}$ compared with control group. AS results above. And MLE5 had anti-ischemic effect by inhibiting TGF-${\alpha}$ production, and by accelerating IL-10 and TGF-${\beta}$ production.