• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.35-36
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• 2008

PTC thermistor are characterized by an increase in the electrical resistance with temperature. The PTC materials of middle Curie point were produced or that of high Curie point (above $200^{\circ}C$), it was determined that compositional modifications of $Pb^{2+}$ for $Ba^{2+}$ produce change sin the Curie point to higher temperature. PTC ceramic materials with the Curie point above $120^{\circ}C$ were prepared by adding $PbTiO_3$, PbO or $Pb_3O_4$ into $BaTiO_3$. Thereby, adding $Pb^{2+}$ into $BaTiO_3$-based PTC material to improve Tc was studied broadly, however, weal know that PbO was poisonous and prone to volatilize, then to pollute the circumstance and hurt to people, so we should dope other innocuous additives instead of lead to increase Tc of composite PTC material. In order to prepare lead-free $BaTiO_3$-based PTC with middle Curie point, the incorporation on $Bi_{1/2}K_{1/2}TiO_3$ into $BaTiO_3$-based ceramics was investigated on samples containing 0, 1, 2, 3, 4, and 50mol% of $Bi_{1/2}K_{1/2}TiO_3$. $Bi_{1/2}K_{1/2}TiO_3$ was compounded as standby material by conventional solid-state reaction technique. The starting materials were $Bi_2O_3$, $K_2CO_3$, $BaCO_3$ and $TiO_2$ powder, and using solid-state reaction method, too. The microstructures of samples were investigated by SEM, DSC, XRD and dielectric properties. Phase composition and lattice parameters were investigated by X-ray diffraction.

• Journal of the Korean Society of Radiology
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• v.6 no.4
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• pp.267-273
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• 2012

Abnormal gastric emptying time of dog by alien substance, neoplasm, pyloric antrum hyperplasia, stomach surgery, electrolyte imbalance, stomach-dilated torsion is clinically important as a digestive disease. Therefore study aims to provide basic data on the clinical usefulness of gastric emptying time test which uses radiopaque Kolomark developed in Korea rather than using the existing BIPS for the dog. 9 beagles were used for this experiment and their average weight was about 10.3kg with 2.5 year-old average age. For the test, fast for 12 hours was made without chemical sedation, and just before the test, 1 capsule of Kolomark was fed with 25% of daily feed amount, and we took photographs at ventrodorsal and right lateral position after 2, 4, 8 and 12 hours. As for interested reading area, we observed entire stomach from cardia to stomach pyloric part, and as for analysis method, we counted Kolomarks remained in the stomach per time and judged only P value below 0.05 to be meaningful by using Friedman Test. After feeding Kolomark through oral cavity, it took average 7.55 hours for the Kolomark to have escaped from the stomach to small intestine. In this study of gastrointestinal tract passing time after feeding matured dog, we used Kolomark and expect that it could be a basic data for normal gastrokinetic time.

• Research in Plant Disease
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• v.22 no.3
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• pp.178-183
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• 2016

Soybean yellow mottle mosaic virus (SYMMV) is a new emerging plant virus detected in soybean (Glycine max) in Korea. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for rapid detection of SYMMV has been developed. In this study, we have designed primers (SYMM-F3/B3/FIP/BIP) specific to sequences from the coat protein gene of SYMMV genome. Sensitivity analysis showed that RT-LAMP was 10 to 100 times more sensitive than reverse transcription polymerase chain reaction (RT-PCR). The optimal reaction condition of RT-LAMP was determined at $65^{\circ}C$ for 50 minutes. The result indicates that RT-LAMP assay does not require special equipment and long time for SYMMV detection. Therefore, it can be an alternative detection method of RT-PCR in laboratory.

• Korean Journal of Plant Resources
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• v.31 no.2
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• pp.149-161
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• 2018

This study was carried out to investigate the flora of Deokjeongsan Mt. (Ganghwa-gun) from March to October 2016. The vascular plants identified during the 8 round field surveys were a to total of 484 taxa: 107 families, 305 genera, 423 species, 8 subspecies, 48 varieties, 4 forms and 1 hybrid. The plant formation of Deokjeongsan Mt. is the deciduous broad-leaved and conifer mixed forest which is the common one in the middle part of Korean peninsula. All most mountain covered with young secondary forest which is mainly composed of Pinus and Quercus. The plant species diversity largest families were Asteraceae (62 taxa, 12.7%), Poaceae (48 taxa, 9.9%), Cyperaceae (27 taxa, 5.6%), Fabaceae (23 taxa, 4.7%), and Lamiaceae (21 taxa, 4.3%). The four taxa of Korean endemic plants such as Clematis brachyura Maxim., Salix koriyanagi Kimura ex Goerz, Carex brevispicula G. H. Nam & G. Y. Chung, and Hemerocallis hakuunensis Nakai were collected. The vascular plants on the red list according to IUCN evaluation basis were found to be five taxa: Near Threatened (NT) species of Senecio argunensis Turcz., Least Concern (LC) species Pseudoraphis ukishiba Nakai, and Not Evaluate (NE) species of Thladiantha dubia Bunge, Cirsium lineare (Thunb.) Sch. Bip., and Scorzonera austriaca ssp. glabra Lipsch. & Krasch. ex Lipsch., respectively. The floristic regional indicator plants found in this area were 26 taxa comprising one taxa of degree V, two taxa of degree IV, four taxa of degree III, eight taxa of degree II, and 11 taxa of degree I. In addition, the alien plants were identified as 46 taxa and the percentage of naturalized index (NI) was 9.5%, and urbanization index (UI) was 14.3%, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.57-58
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• 2008

PTC thermistor are characterized by an increase in the electrical resistance with temperature. The PTC materials of middle Curie point were produced or that of high Curie point (above $200^{\circ}C$), it was determined that compositional modifications of $Pb^{2+}$ for $Ba^{2+}$ produce change sin the Curie point to higher temperature. PTC ceramic materials with the Curie point above $120^{\circ}C$ were prepared by adding $PbTiO_3$, PbO or $Pb_3O_4$ into $BaTiO_3$. Thereby, adding $Pb^{2+}$ into $BaTiO_3$-based PTC material to improve Tc was studied broadly, however, weal know that PbO was poisonous and prone to volatilize, then to pollute the circumstance and hurt to people, so we should dope other innocuous additives instead of lead to increase Tc of composite PTC material. In order to prepare lead-free $BaTiO_3$-based PTC with middle Curie point, the incorporation on $Bi_{1/2}Na_{1/2}TiO_3$ into $BaTiO_3$-based ceramics was investigated on samples containing 0, 1, 2, 3, 4, and 50mol% of $Bi_{1/2}Na_{1/2}TiO_3$. $Bi_{1/2}Na_{1/2}TiO_3$ was compounded as standby material by conventional solid-state reaction technique. The starting materials were $Bi_{1/2}Na_{1/2}TiO_3$, $BaCO_3$, $TiO_2$ and $Y_2O_3$ powder, and using solid-state reaction method, too. The microstructures of samples were investigated by SEM, DSC, XRD and dielectric properties. Phase composition and lattice parameters were investigated by X-ray diffraction.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.51-60
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• 2016

This study was selected drought tolerant plants, by observing the physiological characteristics and biochemical materials from the 9 kinds of the Compositae plants. After selecting plants of the similar size, and then drought stress was induced by the irrigation stopping. Survival rates, chlorophyll values, relative water content(RWC), excised-leaf water loss(ELWL), proline, reducing sugar were measured after 30 days of stopping irrigation. The species that had high rates of survival were Ainsliaea acerifolia Sch. Bip, Aster koraiensis, Aster scaber, Dendranthema zawadskii(S), however other 5 species were dead. The remaining factors have been determined based on plant species showed a higher survival rate. However, chlorophyll content showed high values in A. acerifolia, A.altaicus var. uchiyamae, A. koraiensis, and will have been determined that has no correlation with survival rates, except for A. acerifolia and A. koraiensis. On the other hand, A. scaber, A. acerifolia, A. koraiensis were determined to be relatively high drought tolerant plants in RWC, ELWL, proline, reducing sugar, it showed a similar correlation with survival rate. As a result of 9 kinds of the Compositae plants A. scaber, A. acerifolia, A. koraiensis were considered relatively higher drought tolerant plants.

• Nutrition Research and Practice
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• v.18 no.1
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• pp.1-18
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• 2024

BACKGROUND/OBJECTIVES: Endoplasmic reticulum (ER) stress in adipose tissue causes an inflammatory response and leads to metabolic diseases. However, the association between vitamin D and adipose ER stress remains poorly understood. In this study, we investigated whether 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) alleviates ER stress in adipocytes. MATERIALS/METHODS: 3T3-L1 cells were treated with different concentrations (i.e., 10-100 nM) of 1,25(OH)₂D₃ after or during differentiation (i.e., on day 0-7, 3-7, or 7). They were then incubated with thapsigargin (TG, 500 nM) for an additional 24 h to induce ER stress. Next, we measured the mRNA and protein levels of genes involved in unfold protein response (UPR) and adipogenesis using real-time polymerase chain reaction and western blotting and quantified the secreted protein levels of pro-inflammatory cytokines. Finally, the mRNA levels of UPR pathway genes were measured in adipocytes transfected with siRNA-targeting Vdr. RESULTS: Treatment with 1,25(OH)₂D₃ during various stages of adipocyte differentiation significantly inhibited ER stress induced by TG. In fully differentiated 3T3-L1 adipocytes, 1,25(OH)₂D₃ treatment suppressed mRNA levels of Ddit3, sXbp1, and Atf4 and decreased the secretion of monocyte chemoattractant protein-1, interleukin-6, and tumor necrosis factor-α. However, downregulation of the mRNA levels of Ddit3, sXbp1, and Atf4 following 1,25(OH)₂D₃ administration was not observed in Vdr-knockdown adipocytes. In addition, exposure of 3T3-L1 preadipocytes to 1,25(OH)₂D₃ inhibited transcription of Ddit3, sXbp1, Atf4, Bip, and Atf6 and reduced the p-alpha subunit of translation initiation factor 2 (eIF2α)/eIF2α and p-protein kinase RNA-like ER kinase (PERK)/PERK protein ratios. Furthermore, 1,25(OH)₂D₃ treatment before adipocyte differentiation reduced adipogenesis and the mRNA levels of adipogenic genes. CONCLUSIONS: Our data suggest that 1,25(OH)₂D₃ prevents TG-induced ER stress and inflammatory responses in mature adipocytes by downregulating UPR signaling via binding with Vdr. In addition, the inhibition of adipogenesis by vitamin D may contribute to the reduction of ER stress in adipocytes.