• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.145-149
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• 2015

The electrochemical behavior of $Nd_2O_3-La_2O_3-NiO$ mixed oxide including rare earth resources has been studied to synthesize $La_{0.5}Nd_{0.5}Ni_5$ alloy in a LiCl molten salt. The $Nd_2O_3-La_2O_3-NiO$ mixed oxide was converted to $NiNd_2O_4$ (spinel) and $LaNiO_3$ (perovskite) structures at a sintering temperature of $1100^{\circ}C$. The spinel and perovskite structures led a speed-up in the electrolytic reduction of the mixed oxide. Various reaction intermediates such as Ni, $NiLa_2O_4$ were observed during the electrochemical reduction by XRD analysis. A possible reaction route to $La_{0.5}Nd_{0.5}Ni_5$ in the LiCl molten salt was proposed based on the analysis result.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.325-331
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• 2022

One of the most important factors in predicting tomato growth and yield is the leaf area. Estimating leaf area accurately is the beginning of an effective tomato plant growth assessment model. To this end, this study was conducted to identify the most effective model for estimating plant leaf area through the measurement of tomato plant leaves. Leaf area (LA), leaf length (L), leaf width (W), and lamina length (La) were measured for all leaves of 5 plants at two-week intervals. The correlation between LA and tomato-leaf-independent variables showed a strong positive relationship with the formulas La × W, L × W, La + W, and L + W. For LA estimation, a linear model using the formula LA = a + b (La² + W²) gave the most accurate estimation (R² = 0.867, RMSE = 88.76). After examining the positions of upper, middle, and lower leaves from September to December, the coefficient of determination (R²) values for each model were 0.878, 0.726, and 0.794 respectively. The most accurate estimation came from the model that used the upper leaves of the plants. The high accuracy of the upper-leaf-based model is judged by the 50% defoliation performed by farmers after October.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.5
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• pp.211-216
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• 2018

The recovery of rare earth elements (REE) including La, Nd and Ce from spent batteries is important issues to reuse scarce resources. Herein, we present a simple recovery process to obtain lanthanum oxide ($La_2O_3$) from spent Ni-MH batteries, and demonstrate the conversion mechanism from $NaLa(SO_4)_2{\cdot}H_2O$ to $La_2O_3$. This strategy requires the initial preparation of $NaLa(SO_4)_2{\cdot}H_2O$ and subsequent metathesis reaction with $Na_2CO_3$ at $70^{\circ}C$. This metathesis reaction resulted in the crystalline lanthanum carbonate hydrate ($La_2(CO_3)_3{\cdot}xH_2O$) powder with plate-like morphology. On the basis of TGA result, the $La_2(CO_3)_3{\cdot}xH_2O$ powder was calcined in air at three different temperatures, that is, $300^{\circ}C$, $500^{\circ}C$, and $1000^{\circ}C$. As the calcination temperature increased, the morphology of powder was changed; prism-like ($NaLa(SO_4)_2{\cdot}H_2O$) ${\rightarrow}$ platelike ($La_2(CO_3)_3{\cdot}xH_2O$) ${\rightarrow}$ aggregated irregular shape ($La_2O_3$). Futhermore, XRD results indicated that the crystalline $La_2O_3$ could be synthesized after the metathesis reaction with $Na_2CO_3$, followed by heat-treatment at $1000^{\circ}C$, along with a change of crystallographic structures; $NaLa(SO_4)_2{\cdot}H_2O$ ${\rightarrow}$ $La_2(CO_3)_3{\cdot}xH_2O$ ${\rightarrow}$ $La_2O_3$.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.229-234
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• 1999

The effects of linoleic acid(LA, 18 : 2) and/or bovine serum albumin(BSA) on the lipid metabolism in human hepatoma cell line HepG2 cells were evaluated. HepG2 cells were cultured in basal Dulbecco's modified Eagle's(DME) medium(Basal medium), DME medium containing 0.2 mM LA(LA medium), or DME medium containing both 0.2 mM LA and 0.2-1.0% BSA(LA+BSA medium). $[^{14}C]Acetate(0.3\;{\mu}Ci/ml\;medium)$ was added as a radioactive lipid precursor and the cells were incubated for 6 hours. An addition of LA to basal medium resulted in a decrease in the incorporation of $[^{14}C]acetate$ into total cholesterol fraction. In contrast, an addition of BSA to LA-containing medium tended to increase the incorporation of $[^{14}C]acetate$ into total cholesterol. The alteration of cholesterol metabolism in HepG2 cells incubated in LA+BSA medium was attributed by an increase in the incorporation of $[^{14}C]acetate$ into free cholesterol, but not cholesteryl ester fraction. In addition, the secretion of cholesterol was increased by LA+BSA medium, suggesting that BSA stimulates cholesterol secretion. No significant change in the incorporation of $[^{14}C]acetate$ into cellular total lipids was observed among the experimental groups. However, an increased incorporation of $[^{14}C]-labelled$ fatty acid into cellular triacylglycerol and decreased incorporation into phospholipid were observed in cells incubated with LA+BSA medium as compared to those of LA medium. The secretions of $[^{14}C]-labelled$ triacylglycerol, phospholipid, and free fatty acid were also stimulated in HepG2 cells incubated with LA+BSA medium. In conclusion, the present study suggests that in human hepatocytes, LA and BSA influence lipid metabolism, and BSA enhances the secretion of lipids.

• Proceedings of the Costume Culture Conference
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• 1998.09a
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• pp.42-43
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• 1998

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.10a
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• pp.136-136
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• 1997

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.11a
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• pp.77-77
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• 1998

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.4
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• pp.47-60
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• 2006

Purpose : This study was conducted to investigate the inhibitory effects of Scutellaria barbata D. D on on the cell proliferation of HeLa Cells. Methods : Human uterine cervical carcinoma HeLa cells were cultured in the 1%, 5% and 10% concentration of Scutellaria barbata D. D on solution for 24, 48 and 72 hours for the direct inhibitory effects of Scutellaria barbata D. D on. Then we examined the effect of Scutellaria barbata D. D on solution on the cell proliferation inhibition by XTT assay. DNA fragmentation, MAP kinase activity and caspase activity by FACS analysis in HeLa cells. Results : We found that the proliferation of HeLa cells was significantly decreased in Scutellaria barbata D. D on solution containing groups comparing with a control group in a concentration-dependant manner. When HeLa cells were cultivated for 24 hours with 5% Scutellaria barbata D. D on solution containing group, the percentage of HeLa cells with activated caspase was the highest. Scutellaria barbata D. D on solution reduced the MAP kinase activity of HeLa cells comparing with the control group. By the XTT assay, the cell's activity was decreased in 5% and 10% Scutellaria barbata D. D on solution containing groups in 24 and 72 hours cultivation and 10% group in 48 hours. DNA fragmentation and caspase-3 activity of HeLa cells, however, were changed insignificantly. Conclusion : From this study we could suggest that Scutellaria barbata D. D on is available to the inhibition and apoptosis of human cervical carcinoma cell line, HeLa cells in vitro.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1005-1012
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• 2009

Lysozyme and the reduction of metabisulfite addition to red wine were evaluated during a winemaking process and after malolactic fermentation (MLF). Treatment, with lysozyme, of the must from Tempranillo grapes and at the end of alcoholic fermentation (AF) caused the 100% implantation of the inoculated bacterial strain and shortened the duration of MLF by 7 days. At the end of the MLF, wines treated with lysozyme showed lower volatile acidity, color intensity, and biogenic amine content. The differences in color intensity disappeared during wine stabilization. The lysozyme addition after MLF led to lower histamine concentrations in wines. These phenomena occurred irrespective of the lactic acid bacteria (LAB) proliferation control and of the Oenococcus oeni dominant strain identified at this period. The results of this study show the significance of preventive use of lysozyme in vinification of red wine to maintain low histamine levels and ensure a successful implantation of inoculated O. oeni starters.

• Advances in pediatric surgery
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• v.13 no.1
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• pp.52-60
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• 2007

Pediatric laparoscopic appendectomy is controversial particularly in complicated appendicitis. We evaluated the outcomes of laparoscopic appendectomy (LA) and open appendectomy (OA) in simple appendicitis and complicated appendicitis respectively. Since June 2004, initial LA has been our policy in all appendicitis including complicated ones. A total of 160 patients were included in this study, consisting of 80 OA (August 2001 - August 2003) and 80 LA (June 2004 - June 2006). We compared the operating time, the length of hospital stay, the length of antibiotics use, and the postoperative complications between LA and OA. In simple appendicitis (73), there were no differences between LA and OA. However in the 87 patients with complicated appendicitis, the operating time was longer in LA (64.8 min vs. 50.2 min) but the length of hospital stay was shorter in LA than OA (8.5 days vs. 9.6 days). There was one complication in simple appendicitis group and six in complicated appendicitis group (3 cases in LA, 3 cases in OA). There was no difference in the results of LA versus OA in simple appendicitis. Therefore for simple appendicitis, LA is recommended in consideration of the cosmetic effect (fewer scar). In complicated appendicitis, early discharge was an advantage and there were no differences in complications in LA despite a longer operative time. So we conclude LA can be considered as the first choice of treatment for all pediatric appendicitis including complicated appendicitis. To confirm our impressions, more well controlled randomized prospective studied need to be done.