• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.122-125
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• 2005

‘Johyun’ was a new adlay variety which was developed from three way crosses of (Suwon-6xOkayama)x UCN300-25 at the Northern Agricultural Research Station, Gyeonggi Province ARES. This variety had purple sheath and green leaf blade in primitive growth stage and green leaf and culm in heading stage. Colors of pistil and seed coat were milky-white and dark-brown, respectively. Plant height of Johyun was 179 cm and shortened 22 cm less than Yulmoo-1 which was tested by check variety. Johyun shortened 8 days of heading date and 15 days of ripening date compared with Yulmoo-1. Yield of Johyun was 320 kg/10a of hulled grains in three regional yield trials and 18% higher than Yulmoo-1. This variety was adaptable to single cropping in central and northern region of Korea.

• Restorative Dentistry and Endodontics
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• v.31 no.4
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• pp.312-322
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• 2006

The objectives of this study were to evaluate the effect of surface roughness on the surface color and translucency of the composite resins. Two composite resins (Esthet-X, Dentsply, Milford, USA and Charisma, Kulzer, Domagen, Germany) were used to investigate the surface color. Charisma was used to investigate the translucency. 40 disc samples (diameter: 8 mm, thickness: 5 mm) were made by each product to measure the surface color. Polymerized each sample's one side was treated by Sof-Lex finishing and polishing system (Group C, M, F, SF). 40 disc samples (diameter: 6 mm, thickness: 1 mm) were prepared to measure the opacity. 1 mm samples were ground one side with #600, #1000, #1500 and #2000 sandpapers. CIE $L^{*}a^{*}b^{*}$ values of each 5 mm thickness samples, and XYZ values of 1 mm thickness samples on the white and black background were measured with spectrophotometer (Spectrolino, GretagMacbeth, Regensdorf, Switzerland). Mean surface roughness (Ra) of all samples before and after surface treatment was measured using the Surface Roughness Tester SJ-301 (Mytutoyo, Tokyo, Japan). Regardless of type and shade of the composite resin, $L^{*}$ values measured in group C were higher than others (p < 0.05), and $L^{*}$ value decreased as the Ra value decreased except B3 shade of Esthet-X. But there were no significant difference in $a^{*}$ values among groups. In control group and SF, highest $b^{*}$ values were measured (p < 0.05), except B1 shade of Esthet-X. Contrast ratio decreased as the Ra value decreased (p < 0.05). With the above results, difference of surface roughness has influence on surface color and translucency of dental composite resins.