• Journal of Life Science
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• v.14 no.1
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• pp.91-97
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• 2004

As a part of our study on the improvement of anticonvulsant, here we report the synthesis of N-acyl-$\alpha$-aminosuc-cinimides 1 and N-acyl-$\alpha$-aminoglutarimides 2. (R)-Benzoic acid 4-benzyloxycarbonylamino-2-oxo-pyrrolidin-1-ylester 6a, (R)-4-nifro-benzoic acid 4-benzyloxycarbonylamino-2- oxo-pyrrolidin-1-yl ester 6b, (R) -4-nitro-benzoic acid 4-benzyloxycarbonylamino-2-oxo-pyrrolidin-1-yl ester 6c, and (R)-propionic acid 4-benzyloxycarbonylamino-2-oxo-pyrrolidin-1-yl ester 6d were synthesized from (R)-2-benzyloxy carbonylamino-succinic acid 3 as a starting meterial. (R)-(3- Benzyloxycarbonylamino-2,6-dioxo-piperidin-1-yloxy)-acetic acid methyl ester 10a, (R)-(3-benzyloxycarbonylamino-2,6-dioxo-piperidin-1-yloxy)-acetic acid ethy1 ester 10b, an d (R)-2-(3-benzyloxycarbonylamino-2,6- diox o-piperidin-1-yl oxy)-propionic acid methyl ester l0c were synthesized from (R)- 3-carbobenzyloxy-amino-glutarmic acid 7 as a starting meterial. The yield, mp, IR, $^1H-NMR,\; and^{13}C$- NMR spectra of the products 6a, 6b, 6c, 6d, 10a, l0b, l0c are summarized in footnote. The biological studies of these compounds are in progress and will be reported in future.

• Journal of Applied Biological Chemistry
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• v.48 no.3
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• pp.127-132
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• 2005

MYB genes, comprising group of related genes found in animal, plant, and fungal genomes, encode common DNA-binding domains composed of one to four repeat motifs. MYB genes containing two repeats (R2R3) constitute largest MYB gene family in plants. R2R3 MYB genes play important roles in regulation of secondary metabolism, control of cell shape, disease resistance, and hormone response. Eight-four R2R3 MYB genes were retrieved from rice genome for functional characterization of MYB genes. Analysis of MYB domains revealed each MYB domain contains three ${\alpha}$-helices with regularly spaced tryptophan residues. R2R3 MYB genes were divided into four subfamilies based on phylogenic analysis result. Real-time PCR analysis of 34 MYB genes revealed 12 MYB genes were highly expressed in seeds than in leaves, whereas 4 genes were highly expressed in leaves.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.3
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• pp.221-227
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• 2008

The black rockfish (Sebastes schlegeli) is an important commercial species in Korean fisheries. We used acoustic telemetry using coded ultrasonic transmitters to track the home ranges and homing routes of the black rockfish that inhabit in the Tongyeong marine ranching area. Twenty-four fish were released at five points. The distance from the capture point (C1) to the released point was 0 (R7), 0.2 (R1), 0.9 (R2), 1.3 (R3) and 1.9 (R4) km. Two of the three fish released at R1 (0.2 km) returned home in under 48hrs. Another was found 0.8km from C1. Two of the five fish released at R2 returned home, but it took over 250 days. None of the ten fish released at R3 and R4 returned home. Three of the ten fish moved 1.1-2.6 km from C1 and were found near a cage or a natural reef. Six fish were released at R7. The younger the fish, the wider was its movement range around the artificial reefs. Fish over 3 years old were likely to move less far.

• Bulletin of the Korean Chemical Society
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• v.20 no.5
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• pp.535-538
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• 1999

Five coordinated water-soluble iridium(l) complex, IrH(CO)(TPPTS)3 (1) (TPPTS = P(m-C6H4SO3Na)3-xH2O) has been prepared from the reaction of IrCl3·3H2O with TPPTS and HCHO in H2O/EtOH solution. Complex 1 catalyzes the hydration of nitrites (RC ≡ N, R = CH3, CICH2, CH3(CH2)4, Ph) in aqueous solution to give the corresponding amides (RCONH2) at 100℃. The hydration of unsaturated nitrites (R'C ≡ N, R'=CH3CH=CH, CH3OCH=CH, trans-PhCH=CH, CH2=C(CH3)) takes place regioselectively on-C ≡ N group to give unsaturated amides (R'CONH2) leaving the olefinic group intact. The yields of the amides seem to be depending on the electrophilicity of the carbon of nitrile: The more the electron withdrawing ability of the substituents on nitrites, the more amides are obtained. The hydration of dinitriles (NC-R-CN, R=(CH2)4, (CH2)6) with complex 1 initially gives mono-hydration products (NC-R-CONH2) which are slowly hydrated further to give dihydration products (H2NCO-R-CONH2). The hydration of 1,4-dicyanobutane has been found to be somewhat faster than that of 1,6-dicyanohexane.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.21-27
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• 2019

R-404A, which is used widely in small-scale ice makers, is scheduled to be phased out because of its high global warming potential. In this study, drop-in tests were conducted using R-448A and R-449A, which replace R-404A, to modify the outdoor air and supply water temperatures. The results showed that the daily ice production rate of R-404A was 5.3% higher than that of R-448A and 4.2% higher than that of R-449A. This was attributed to the larger vapor density of R-404A, which resulted in a larger mass flow rate in the system. Between R-448A and R-449A, R-448A yielded a larger amount of ice at low air and water temperatures, whereas R-449A yielded a larger amount of ice at high air and water temperatures. The daily power consumption of R-404A was approximately 10% larger than those of R-448A and R-449A. The resulting COPs of R-448A and R-449A was similar, only 3.0% larger than that of R-404A. The literature survey showed that the condensation or evaporation data of R-448A or R-449A are very limited, and research on this issue is recommended.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.512-515
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• 2004

The purpose of this experiment was to obtain informations about variation of anthocyanin content within black-seeded soybean testa according to cultivation and harvest time. Three varieties, Ilpumgeomjeongkong, Geomjeongkong 2, Tawonkong were tested in this experiment. Seeds were planted on April 15 (early planting), May 15 (optimum planting), and June 15 (late planting), respectively. Harvest time was R6 (full seed), R7 (physiological maturity), and R8 (harvest maturity), respectively. The content of delphinidin-3-glucoside (D3G), cyanidin-3-glucoside (C3G), petunidin-3-glucoside (Pt3G), and total anthocyanin (TA) had all increased gradually from April 15 to June 15 as well as R6 to R8. There was no varietal difference in D3G, but C3G and TA of Geomjeongkong 2 were higher than other two varieties. Pt3G was the highest Tawonkong of varieties. The value of L as anthocyanin color difference had gradually decreased from April 15 to June 15 and R6 to R8, Geomjeongkong 2 among three varieties was the lowest. The value of a was the highest on May 15 and increased gradually from R6 to R8, Geomjeongkong 2 was the lowest. The value of b was the highest on June 15 as late planting and was the highest Geomjeongkong 2 of varieties. The value of b had increased gradually from R6 to R8. D3G, C3G, Pt3G, and TA contents showed mutually high positive correlation and these four characters were represented high negative correlation with L value but showed high positive correlation with a and b values. The value of L showed high negative correlation with a and b values. The value of a showed high positive correlation with b value.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.1
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• pp.20-29
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• 2009

This study was performed to evaluate the effect of the shrinkage stress induced by polymerization process of several light curing filling materials according to filling methods. High power light curing unit which has a plasma arc lamp was used and filling materials used were Filtek $Z-250^{(R)}$ composite resin, $Dyract^{(R)}$ AP compomer and $Tetric^{(R)}$ Flow flowable composite resin. Cavities were prepared on the permanent molars with width 3 mm, height 3 mm and depth 1.5 mm and the filling materials were filled with 1 step, 2 step layering technique and 3 step oblique filling methods. The results can be summarized as follows; 1. Strain values showed rapid increase from the start of light curing followed by gradual decrease afterwards with time. 2. Although the shrinkage stress value of $Z-250^{(R)}$ were shown to be relatively higher than $Dyract^{(R)}$ AP and $Tetric^{(R)}$ Flow, no statistically significant could be found between tested materials(p>0.05). 3. There were no statistically significant difference between 3 filling methods when using $Dyract^{(R)}$ AP and $Z-250^{(R)}$(p>0.05). 4. There were no statistically significant difference between shrinkage stress values obtained from samples prepared by different filling methods and materials(p>0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.1
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• pp.22-30
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• 2008

Purpose: The purpose of this study is to compare three different CAD/CAM systems through the fracture strength of zirconia core and to evaluate the clinical availability of each system. Material and methods: The following three groups of 30 maxillary mesial incisor core for all-ceramics(each group 10) were fabricated as follows: group 1. $Adens^{(R)}$ CAD/CAM system, group 2. $Cerasys^{(R)}$ CAD/CAM system, group 3. 3M $Lava^{(R)}$ CAD/CAM system. All specimens were manufactured consistently thickness 0.5mm and relief $40{\mu}m$. Specimens were subjected to compressive loading on the lingual area by Z250/$SN5S^{(R)}$. Each group's mean and standard deviation were calculated and Kruskal Waillis test, Wilcoxon Rank Sum test were utilized to find out the relationship among the groups. Results: The results were as follows: 1. The mean fracture strength of $Adens^{(R)}$ system was $615.89{\pm}156.1N$, the $Cerasys^{(R)}$ system was $863.98{\pm}151.5N$, and the 3M $Lava^{(R)}$ system was $1143.1{\pm}286.6N$. 2. The fracture strength of the systems showed the significant statistical differences in order of 3M $Lava^{(R)}$ system, $Cerasys^{(R)}$ system, $Adens^{(R)}$ system. Conclusion: In this study, in spite of the differences among the groups, every group showed clinically useful results. It is necessary to study further clinical experiments on a long term basis.

• YAKHAK HOEJI
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• v.42 no.3
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• pp.233-237
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• 1998

Activity-guided fractionation and repeated column chromatography afforded two cytotoxic compounds R-3 and R-4 from the root of Rumex japonicus HOUTT. Compou nds were identified as musizin and emodin, respectively, by the physicochemical and spectral data. Besides R-3 and R-4, two compounds R-1 and R-2, chrysophanol and physcion, respectively, were also isolated. The compound R-3 and R-4 exhibited cytotoxicity against cultured human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF498 and HCT15 with $ED_{50}$ values ranging from 2.68 to $10.06{\mu}g/ml$.

• Bulletin of the Korean Mathematical Society
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• v.53 no.3
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• pp.885-902
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• 2016

In this paper we begin the study of $L_k$-2-type hypersurfaces of a hypersphere ${\mathbb{S}}^{n+1}{\subset}{\mathbb{R}}^{n+2}$ for $k{\geq}1$ Let ${\psi}:M^3{\rightarrow}{\mathbb{S}}^4$ be an orientable $H_k$-hypersurface, which is not an open portion of a hypersphere. Then $M^3$ is of $L_k$-2-type if and only if $M^3$ is a Clifford tori ${\mathbb{S}}^1(r_1){\times}{\mathbb{S}}^2(r_2)$, $r^2_1+r^2_2=1$, for appropriate radii, or a tube $T^r(V^2)$ of appropriate constant radius r around the Veronese embedding of the real projective plane ${\mathbb{R}}P^2({\sqrt{3}})$.