• Journal of Biomedical Engineering Research
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• v.16 no.3
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• pp.367-375
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• 1995

Ampicillin sodium (AMP-Na) was loaded Into fibrin glue (FG) in two different ways and was tried to achieve sustained release from FG. One was loading of AMP-Na in a simple mixing and the other was loading of bovine serum albumin (BSA) microspheres which contained ANP-Na. In case of simple mixing, the release control of AWP-Na from FG was tried by variation of FBNG concentration, but failed. However, the loading of BSA mlcrosphere containing ANP-Na into FG showed sustained re- lease of AMP-Na, especially when microsphere was crosslinked with glutaraldehyde (tO.9 : 33hr). The maximum adhesive strength of FG showed at concentration of FBWG and thrombin, 5.0 % and 25-50 NIHU/ml, respectively. The concentration of Factor Xlll (0-500 U/1g of FBNG) did not affect the adhesive strength of FG. The optimal incubation time was 60 min. The AMP-Na or BSA microsphere which was loaded into FG had no significant effect on the adhesive strength of FG.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.25-32
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• 2010

The present study aimed to examine the effects of ${\gamma}$-linolenic acid (GLA) supplementation to in vitro culture (IVC) medium on in vitro developmental competence, freezability and morphology of in vitro matured and fertilized bovine embryos. In vitro produced (IVP) bovine zygotes were cultured in IVC medium supplemented with 0 (negative control), 15, 31, 62, 125, 250, 500 or 1,000 ppm GLA, 250 ppm linoleic acid albumin (LAA) and without any supplement as a control. Day 6 blastocysts derived from culture control were cultured in IVC medium containing either 62, 250 GLA or 250 LAA for 24 h, and at Day 7 were subjected to freezing or morphological examination by electron microscope. GLA 15 showed a tendency to have a higher cleavage rate at Day 2 (70.3%) than other groups. The hatching rate at Day 9 in LAA (38.2%) was significantly higher than the control and all treatment groups (p<0.05), while the blastocyst rate in LAA (32.4%) did not differ from those of 15 (30.5%), 31 (27.1%), and 62 GLA (33.1%) or the control (35.1%). GLA in concentrations of 125, 250, 500, and 1,000 ppm had significantly detrimental effect on the blastocyst rate compared to 15, 31 and 62 ppm GLA, LAA, and control groups (p<0.05). In contrast, the highest post-thaw survival rate (100%) was observed in the control group (p<0.01). Large lipid droplets were observed in the cytoplasm of trophoblastic cells, even in the control, but were abundant in GLA groups. Taking the results of the study into consideration, the addition of GLA to the culture medium for IVP bovine embryos at the dose of 15 ppm increased the developmental competence of zygotes and enhanced the cleavage rate up to Day 2. However, blastulation rate and post-thaw survival were not increased when GLA was added to the culture media.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.557-563
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• 2016

To improve the germination of Spiraea fritschiana seeds for mass propagation, we evaluated the effect of a range of temperatures, cold stratification periods, and gibberellic acid ($GA_3$) treatments on three germination characteristics. Final germination percentage (FGP) increased as the temperature for seed germination increased, up to $30^{\circ}C$, while the mean germination time (MGT) and the mean number of days to 30% germination ($T_{30}$) decreased when seeds were germinated at $25-30^{\circ}C$. The optimum germination temperature of S. fritschiana seeds is approximately $30^{\circ}C$ considering FGP, MGT, and $T_{30}$ together. FGP increased with the duration of cold stratification up to a period of 6 weeks, but declined after 8 weeks of cold stratification, as prolonged cold stratification can induce dormancy with a resultant decline in germination. Pretreatment with 6-8 weeks of cold stratification or soaking seeds in distilled water or $500mg{\cdot}L^{-1}$ $GA_3$ for 24 h accelerated and increased the germination of S. fritschiana seeds, regardless of temperature. However, further study might be required to evaluate the effect of $GA_3$ concentrations lower than $500mg{\cdot}L^{-1}$ on the promotion of germination in S. fritschiana seeds.

• Journal of the Mineralogical Society of Korea
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• v.15 no.3
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• pp.161-169
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• 2002

high pressure and temperature conditions. However, those results are not consistent with one another, and phase boundary between ilmenite and perovskite phases determined only from the quenching method may be not so reliable at all. Therefore, in-situ high pressure-temperature (hP-T) X-ray diffraction measurements were performed up to 19 GPa and $700^{\circ}C$ in a large volume press apparatus using synchrotron radiation. Experimental results show that perovskite phase is stable at pressures above 16 GPa, and transforms back to $LiNbO_3$phase near 15 CPa at room temperature, and that the perovskite-ilmenite transition is back and forth near 15 CPa at $500^{\circ}C$. LiNbO$_3$phase transforms to ilmenite at 13 CPa and $300^{\circ}C$ and at 10.8 CPa and $400^{\circ}C$, respectively. These data indicate that $LiNbO_3$phase may have a stability region in the hP-T phase diagram and that the perovskite-ilmenite phase boundary would be quite different from that previously reported.

• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.86-93
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• 2018

Recently, the use of composite steel plate concrete structural modules filled with concrete between steel plates of complex internal structure, in which a large amount of studs are installed, is increasing in order to reduce the weight and to increase workability of structures such as LNG storage tanks. However, in Korea, there is no systematic criterion for evaluating the construction performance of composite steel plate concrete structural modules. Therefore, in this study, we propose a filling guideline of concrete for composite steel plate structural module. For this purpose, high filling performance concrete with general strength range was formulated and tested for filling ability and permeability for each formulation. Rheology analysis was performed to quantitatively evaluate the flow characteristics of concrete. The reliability of $T_{500}$ and plastic viscosity was evaluated to reflect the results of each test, and a guideline for high filling concrete satisfying the reliability of 0.9 or more was derived by reflecting the results of the study on the relationship between the $T_{500}$ and plastic viscosity. Through final fill-box test, filling performance was verified and guidelines were suggested.

• Journal of Korean Traditional Oncology
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• v.15 no.1
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• pp.37-45
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• 2010

Bojungbangdocktang (BJBDT), a formula of eight Oriental herbs, is a modified herbal prescription of Bangdoktang and Bojungbangamtang. Recently, BJBDT was demonstrated to inhibit angiogenesis induced by vascular endothelial growth factor in human umbilical vein endothelial cells, enhance hematopoiesis and protect cisplatin-induced cytotoxicity in normal MCF-10A breast cells. Nevertheless, there is no safety study of BJBDT before clinical trial so far. Thus, in the current study, we investigated the toxicity about ethanol-extracted BJBDT. Male and female Spraque Dawley (SD) rats were given orally by BJBDT at 250, 500, and 1000 mg/kg for 4 weeks. Mortality, clinical signs and measured change of body weight, food consumption and water consumption were observed. In addition, we performed ophthalmologic, urinary, hematological, blood serum biochemical and histopathological examination. Any general toxicity was not found in BJBDT treated group. Also, there were no significant differences in the parameters such as body weight, food consumption and water consumption, a lot of urine and blood factor levels except HCT, MCHC, Ca, TG, Glucose and T-Bilirubin level compared with control group. Although HCT was elevated and TG was decreased in male rats, and MCHC, Glucose and T-Bilirubin were elevated and Ca and HCT were decreased in female rats, these were within normal ranges. Finally, we determined that maximum tolerated dose (MTD) was 1000 mg/kg and no observed adverse effect level (NOAEL) was 500 mg/kg. Taken together, these results demonstrated that BJBDT is very safe to SD rats.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.673-679
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• 2008

In this study, Mesoporous silica were prepared from hydrothermal synthesis using gel mixture of tetraethylorthosilcate (TEOS) as silica source and cetyltrimethylammonium bromide(CTMABr) as a template. In the optimum synthesis cause, molar ratio of template and silica changed. The surface and structure properties of Mesoporous silica were determined by XRD, SEM, and BET. N$_2$ adsorption isotherm characteristics, including the specific surface area(S$_{BET}$), total pore volume(V$_T$), and average pore diameter(D$_{BJH}$), were determined by BET. Also, the adsorption character of Pb(II) and Cd(II) ion on Mesoporous silica were measured using ICP. As a result, a SBET of 100$\sim$1,500 m$^2$/g was determined from the N$_2$ adsorption isotherm. Also, the average pore diameter of 2$\sim$4 nm. The adsorption of Pb ion and Cd ion on Mesoporous silica become different depending on the pH of solution. The adsorption amount of Mesoporus silica had higher than that of silicagel.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.361-367
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• 2018

The purpose of this study was to evaluate the influence of hydrofluoric acid etching treatment on the bonding strength of yttria-stabilized tetragonal zirconia polycrystal(Y-TZP). Four groups of zirconia-resin cement specimens were prepared; 1) ZGS group (zirconia, no treatment), 2) ZGSH group (zirconia, hydrofluoric acid etching treatment) 3) H-ZGS group (Hybrid zirconia, no treatment) 4) H-ZGSH group (Hybrid zirconia, hydrofluoric acid etching treatment). The shear bond strength between zirconia and porcelain was measured using a Instron Universal Testing Machine(Model DBBP-500, Instron Corporation, Kyonggi, Korea). Data were statistically analyzed using independent t-test and two-way ANOVA(${\alpha}=0.05$). The ceramic-resin cement bonding strength was affected by hydrofluoric acid etching treatment(p<0.05). Digital microscope examination of the fracture surface showed mixed failures with adhesive and cohesive types in hydrofluoric acid etching treatment with treated zirconia and hybrid zirconia groups.

• Progress in Superconductivity
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• v.12 no.2
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• pp.82-87
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• 2011

We studied the trapped field properties of bulk Y-Ba-Cu-O superconductors by applying 3 T of the permanent or $Nb_3Ti$ superconducting magnet. The 28 mm circular type of YBCO bulk superconductor was prepared and then hole at the center of bulk, parallel to the c-axis, was mechanically drilled. Typical size of hole in YBCO bulk was 10 mm in diameter. In order to examine the trapped field variation in terms of different impregnated materials, a hole in YBCO bulk was filled with resin and indium respectively. The trapped field decay due to flux flow was determined in terms of time. Our preliminary result indicates the trapped field value measured on the YBCO without hole after 30 minute by applying 3 T, was 6,500 G, which is much higher than that, 4,500 G, measured on YBCO with hole. Also, we confirmed that the tendency of a trapped field decrement with time was almost the same regardless of the impregnated materials in YBCO.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.355-361
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• 1999

We have synthesized the soluble polymide based side chain system with covalently attached NLO chromophore Disperse Red 1. The developed polymer is optically transparent in the range of optical communication wave-lengths. Its glass transition temperature$(T_g)$ and thermal decomposition temperature$(T_d)$ are $225^{\circ}C, 310^{\circ}C$ respectively. The poled film with the poling field of $100 V/\mu\textrm{m}$ shows that the dielectric constant is 3.37 at the 10-kHz frequency, the refractive indices of TM and TE modes are both 1.631 at $\lambda = 1300 nm$, and the Electro-optic coefficients are 4.6~9.2 pm/V at $\lambda = 1300 nm$. There are no decays of the EO coefficient in the poled polymer at $180^{\circ}C$ in one hour, and $90^{\circ}C$ in 500 hours.