• Korean Journal of Plant Taxonomy
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• v.33 no.3
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• pp.279-293
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• 2003

Somatic chromosomes about 13 taxa of Korean Euphorbia L. was investigated to estimate its taxonomic significance. Somatic chromosome numbers of treated taxa were 2n= 12, 20, 22, 28, 40, 42, 56, therefore basic chromosome numbers of those were x=6, 7, 10, 11. The chromosome numbers of E. pallasii Turcz. (2n=20), E. hylonoma Hand.-Mazz (2n=20.), E. fauriei H. L$\acute{e}$v. & Vaniot ex H. L$\acute{e}$v (2n=28) and E. jolkini Boiss. (2n=28) were determined for the first time in this study. The chromosome numbers of four taxa were same as previous ones; E. sieboldiana Moor. & Decne. (2n=20), E. ebracteolata Hayata (2n=20), E. humifusa Willd. ex Schlecht. (2n=22). But those of six taxa were different; E. esula L (2n= 16, 20, 60, 64 vs 2n=20), E. helioscopia L. (2n=12, 42 vs 2n=42), E. lucorum Rupr. (2n=28, 40 vs 2n=56), E. pekinensis Rupr. in Maxim. (2n=24 vs 2n=28, 56), E. maculata L. (2n=28, 42 vs 2n=12), E. supina Raf. (n=7 vs 2n=40). E. ebracteolata, E. pallasii and E. hylonoma were distingushcd from the other taxa by the chromosome numbers, size and satellites, E. maculata, E. humifusa, E. supina had the different basic and somatic chromosome numbers in spite of the similar morphological. anatomical and palynological chracters. The chromosomal character of Korean Euphorbia was supported the Ma and Hu's systems, and as above results, it was found to be a good character in delimiting above sections and estimating relationships for some species.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.85-93
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• 1995

Acidic and alkaline hydrolysis of diol-type ginseng saponins produced a new glycoside, (20E)-ginsenoside Rh$_{3}$, and its stereoisomer (20Z)-, which were further subjected to alkaline by drolysis to give their aglycones, (20E)- and (20Z)-3$\beta$, 12$\beta$-dihydroxy-dammar-20(22),24-diene. The ratio of stereoisomeric mixtures was estimated to be ca. 5:1 from intensities of the peaks in $^{1}$H- and $^{13}$C-NMR spectra. The $^{1}$H- and $^{13}$C-NMR signals of ginsenoside Rh$_{3}$, which have remained unclarified, were completely assigned by the extensive application of modern NMR techniques.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.330-342
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• 2003

The formation of emulsions and micelles in water/ceramide PC104/CholE $O_{20}$/C$_{16}$E $O_{20}$ and water/ceramide PC104/CholE $O_{20}$ mixtures was investigated through the phase behavior studies. The phase diagrams showed the existence of micelle and emulsion regions in both systems. The mixed surfactant system (CholE $O_{20}$/C$_{16}$E $O_{20}$) showed the wider micellar and emulsion regions than the single surfactant system (CholE $O_{20}$). From FT-IR measurements, it was found that the polyoxyethylene (POE) groups of surfactants formed the hydrogen bonds with amido carbonyl group in ceramide PC104. This result indicated that the hydrophilic part (EO) of surfactants could stabilize the lamellar structure and emulsion of ceramide PC104. The mixed surfactant system (CholE $O_{20}$/C$_{16}$E $O_{20}$) resulted in the smaller emulsion droplet size due to the effect of curvature at the interface, thus further increasing emulsion stability. With the penetration of $C_{16}$E $O_{20}$into the interfacial layer of surfactants in emulsion, the curvature of the interface might be altered for the formation of smaller emulsion droplets. The mixed surfactant system could incorporate up to 4 wt. % of ceramide PC104 into emulsion more than single surfactant system.ystem.m.

• The Journal of the Petrological Society of Korea
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• v.27 no.3
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• pp.109-120
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• 2018

The distributional characteristics of fault segments in Cretaceous and Tertiary rocks from southeastern Gyeongsang Basin were derived. The 267 sets of fault segments showing linear type were extracted from the curved fault lines delineated on the regional geological map. First, the directional angle(${\theta}$)-length(L) chart for the whole fault segments was made. From the related chart, the general d istribution pattern of fault segments was derived. The distribution curve in the chart was divided into four sections according to its overall shape. NNE, NNW and WNW directions, corresponding to the peaks of the above sections, indicate those of the Yangsan, Ulsan and Gaeum fault systems. The fault segment population show near symmetrical distribution with respect to $N19^{\circ}E$ direction corresponding to the maximum peak. Second, the directional angle-frequency(N), mean length(Lm), total length(Lt) and density(${\rho}$) chart was made. From the related chart, whole domain of the above chart was divided into 19 domains in terms of the phases of the distribution curve. The directions corresponding to the peaks of the above domains suggest the directions of representative stresses acted on rock body. Third, the length-cumulative frequency graphs for the 18 sub-populations were made. From the related chart, the value of exponent(${\lambda}$) increase in the clockwise direction($N10{\sim}20^{\circ}E{\rightarrow}N50{\sim}60^{\circ}E$) and counterclockwise direction ($N10{\sim}20^{\circ}W{\rightarrow}N50{\sim}60^{\circ}W$). On the other hand, the width of distribution of lengths and mean length decrease. The chart for the above sub-populations having mutually different evolution characteristics, reveals a cross section of evolutionary process. Fourth, the general distribution chart for the 18 graphs was made. From the related chart, the above graphs were classified into five groups(A~E) according to the distribution area. The lengths of fault segments increase in order of group E ($N80{\sim}90^{\circ}E{\cdot}N70{\sim}80^{\circ}E{\cdot}N80{\sim}90^{\circ}W{\cdot}N50{\sim}60^{\circ}W{\cdot}N30{\sim}40^{\circ}W{\cdot}N40{\sim}50^{\circ}W$) < D ($N70{\sim}80^{\circ}W{\cdot}N60{\sim}70^{\circ}W{\cdot}N60{\sim}70^{\circ}E{\cdot}N50{\sim}60^{\circ}E{\cdot}N40{\sim}50^{\circ}E{\cdot}N0{\sim}10^{\circ}W$) < C ($N20{\sim}30^{\circ}W{\cdot}N10{\sim}20^{\circ}W$) < B ($N0{\sim}10^{\circ}E{\cdot}N30{\sim}40^{\circ}E$) < A ($N20{\sim}30^{\circ}E{\cdot}N10{\sim}20^{\circ}E$). Especially the forms of graph gradually transition from a uniform distribution to an exponential one. Lastly, the values of the six parameters for fault-segment length were divided into five groups. Among the six parameters, mean length and length of the longest fault segment decrease in the order of group III ($N10^{\circ}W{\sim}N20^{\circ}E$) > IV ($N20{\sim}60^{\circ}E$) > II ($N10{\sim}60^{\circ}W$) > I ($N60{\sim}90^{\circ}W$) > V ($N60{\sim}90^{\circ}E$). Frequency, longest length, total length, mean length and density of fault segments, belonging to group V, show the lowest values. The above order of arrangement among five groups suggests the interrelationship with the relative formation ages of fault segments.

• The Journal of Korean Medicine
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• v.23 no.1
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• pp.120-132
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• 2002

Objectives : The purpose of this investigation was to evaluate the effect of Goomicheongsim-won Extracts on E20 corticells and P7 cerebellar cells exposed to hypoxia, and the effect on neuronal protection by elimination of Rhinoceros unicornis L. and/or Orpiment $As_2S_3$. Methods : P7 cerebellar cells were grown in various concentrations of KM-A, KM-B, KM- C and KM-D. On 7 DIV (day in vitro), cells were exposed to hypoxia (98% $N_2/5%{;}CO_2,{\;}3{\;}hr,{\;}37^{\circ}C$) and normoxia, and then further incubated for 3 days. Neuronal viabilities were expressed as percentages of control. E20 cortical cells were grown in various concentrations of KM-A, KM-B, KM-C, and KM-D. On 7 DIV, cells were exposed to hypoxia and normoxia, and then further incubated for 3 and 7 days. Results : I. The effect of KM-A on neuronal protection was significantly increased P7 cerebellar granule cells and E20 cortical cells on normoxia and hypoxia. 2. The effect of KM-B on neuronal protection was increased P7 cerebellar granule cells on normoxia, but was significantly decreased P7 cerebellar granule cells on hypoxia. The effect of KM-B on neuronal protection was non-significantly increased E20 cortical cells on normoxia and hypoxia. 3. The effect of KM-C on neuronal protection was non-significantly increased P7 cerebellar granule cells on normoxia and hypoxia and was decreased (p=0.058) on hyperconcentration of the extracts in normoxia. The effect of KM-C on neuronal protection was significantly increased P7 cerebellar granule cells and E20 cortical cells on normoxia and hypoxia (10 DIV), and the effect was E20 cortical cells on normoxia (14 DIV), non-significantly increased E20 cortical cells on hypoxia (14DIV). 4. The effect of KM-D on neuronal protection was increased P7 cerebellar granule cells on normoxia but was not on hyperconcentration of the extracts, was significantly decreased on hyperconcentration of the extracts in hypoxia. The effect of KM-D on neuronal protection was significantly increased E20 cortical cells on normoxia and was significantly increased E20 cortical cells increased on hypoxia (10 DIV). Conclusions : Goomicheongsim-won extracts had applicable effect on E20 corticells and P7 cerebellar cells exposed to hypoxia. The effect on neuronal protection by elimination of Rhinoceros unicornis L. and/or Orpiment $As_2S_3$ was changed.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.396-401
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• 2013

Alternating copolymers, poly[9-(2-octyl-dodecyl)-9H-carbazole-alt-4,7-di-thiophen-2-yl-benzo[1,2,5]thiadiazole] (PCD20TBT) and poly[9,10-bis-(2-octyl-dodecyloxy)-phenanthrene-alt-4,7-di-thiophen-2-yl-benzo[1,2,5]thiadiazole] (PN40TBT), were synthesized by the Suzuki coupling reaction. The copolymers were soluble in common organic solvents such as chloroform, chlorobenzene, 1,2-dichlorobenzene, tetrahydrofuran and toluene. The maximum absorption wavelength and the band gap of PCD20TBT were 535 nm and 1.75 eV, respectively. The maximum absorption wavelength and the band gap of PN40TBT were 560 nm and 1.97 eV, respectively. The HOMO and the LUMO energy level of PCD20TBT were -5.11 eV and -3.36 eV, respectively. As for PN40TBT, the HOMO and the LUMO energy level of PCD20TBT were -5.31 eV and -3.34 eV, respectively. The polymer solar cells (PSCs) based on the blend of copolymer and PCBM (1 : 2 by weight ratio) were fabricated. The power conversion efficiencies of PSCs based on PCD20TBT and PN40TBT were 0.52% and 0.60%, respectively. The short circuit current density ($J_{SC}$), fill factor (FF) and open circuit voltage ($V_{OC}$) of the device with PCD20TBT were $-1.97mA/cm^2$, 38.2% and 0.69 V. For PN40TBT, the $J_{SC}$, FF, and $V_{OC}$ were $-1.77mA/cm^2$, 42.9%, and 0.79 V, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.1 no.2
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• pp.37-42
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• 1996

The $Bi_{12}(Si,Ge)O_{20}$ single crystals were prepared by Czochralski method and the study of electrical and optical properties were carried out. The activation energy of the electrical conductivity was $E_g$=1.12 eV. The optical energy gap measured in the room temperature is found to be 2.3 eV. A.c. conductivity of crystal $Bi_{12}(Si,Ge)O_{20}$ was measured at temperatures from 290 K to 570 K in the frequency range from 50 kHz to 30 MHz. The a.c. conductivity is proportional to ${\omega}^s$. In view of this it should be hopping conduction mechanisms. At high frequencies, the power exponent was s=2. The low frequency dielectric constants were 54 for $Bi_{12}(Si,Ge)O_{20}$ and 41 for $Bi_{12}(Si,Ge)O_{20}$ single crystals.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.116-124
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• 2019

Background: Ginsenosides are known as the principal pharmacological active constituents in Panax medicinal plants such as Asian ginseng, American ginseng, and Notoginseng. Some ginsenosides, especially the 20(R) isomers, are found in trace amounts in natural sources and are difficult to chemically synthesize. The present study provides an approach to produce such trace ginsenosides applying biotransformation through Escherichia coli modified with relevant genes. Methods: Seven uridine diphosphate glycosyltransferase (UGT) genes originating from Panax notoginseng, Medicago sativa, and Bacillus subtilis were synthesized or cloned and constructed into pETM6, an ePathBrick vector, which were then introduced into E. coli BL21star (DE3) separately. 20(R)-Protopanaxadiol (PPD), 20(R)-protopanaxatriol (PPT), and 20(R)-type ginsenosides were used as substrates for biotransformation with recombinant E. coli modified with those UGT genes. Results: E. coli engineered with $GT95^{syn}$ selectively transfers a glucose moiety to the C20 hydroxyl of 20(R)-PPD and 20(R)-PPT to produce 20(R)-CK and 20(R)-F1, respectively. GTK1- and GTC1-modified E. coli glycosylated the C3-OH of 20(R)-PPD to form 20(R)-Rh2. Moreover, E. coli containing $p2GT95^{syn}K1$, a recreated two-step glycosylation pathway via the ePathBrich, implemented the successive glycosylation at C20-OH and C3-OH of 20(R)-PPD and yielded 20(R)-F2 in the biotransformation broth. Conclusion: This study demonstrates that rare 20(R)-ginsenosides can be produced through E. coli engineered with UTG genes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.251-264
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• 1992

Distribution of indicator species of copepods and chaetognaths were studied as an indicator species of water mass in the southeastern area of the Yellow Sea. Undinula darwini, Lucicutia flavicornis, Pleuromamma gracilis, Euchaeta resselli, Euchaeta plane and Sagitta enflata were found to be reliable indicator species for determining warm water mass. Of these species, E. plana and E. rusrelli have a weak tolerance on the low temperature. Sagitta crassa was indicator species of neritic waters; Sagitta bedoti was that of mixing waters. Centropages abdominalis represented neritic cold waters. In February, U darwini, L. flavicornis, P. gracilis, E. russelli, E. plana and S. enflata occurred in the western waters of Cheju-Do where warm waters over $14^{\circ}C$ occupied. Centropages abdominalis occurred in the northern area beyond Chindo with water temperature less than $10^{\circ}C$. E. plana, E. russelli and S. bedoti were found at the regions between Cheju-Do and Chindo where the water temperature was $12- 14^{\circ}C$ corresponding to the mixing waters. Based on cluster analysis and T-S diagram in February three different water masses were identified from the south to the north. In August, water masses were analyzed at two different layers, 0-20m and 20m- bottom layers, separated by bhermocline depth. In 0-20m layer, E. plana and E. russelli were found from the western waters of Cheju-Do to Daehuksando. In 20m- bottom layer, E. russelli and E plena occurred at the northwestern waters of Cheju-Do with the water temperature warmer than $12^{\circ}C.\;C.$ abdominalis was found at the northern area beyond Chindo. Based on the cluster analysis and T-S diagram in August three different water masses at 0-20m and 20m-bottom layers were identified from the coast to the offshore. C. abdominalis was found at the adjacent water of Chindo at 0-20m layer and the northern area beyond Chindo at 20m~bottom layer. This fact suggested that the cold water mass existed at tile adjacent waters of Chindo in summer.

• Journal of the Korean Ceramic Society
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• v.37 no.3
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• pp.219-226
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• 2000

Amorphous Ge20As20Se60 chalcogenide thin films were prepared by spin coating technique from mixed solutions of As40Se60 and Ge40Se60 dissolved in ethylenediamine. Films were prepared at a roating speed of 3500 rpm and spinning time was 10 second and heat-treateed at 27$0^{\circ}C$ for 1 hour. The resulting film thickness and RMS roughness were approximately 340 nm and 15$\AA$. Photostructure changes were investigated with 514.5nm Ar+ laser irradiation and heat-treatment. After Ar+ laser irradiation, transmittance and transmission efficiency decreased respectively up to 24.9% at 2.43 eV and 67.5% at 3.27 eV, and absorption edge shifted toward long wavelength. Optical bandgap changed from 2.03 to 1.83 eV, and absoprtion coefficient and absorption efficiency increased up to 0.33$\times$105cm-1 at 3.37eV and 88.3% at 1.31 eV, respectively. These photodarkening state were recovered reversibly by heat-treatment at 27$0^{\circ}C$ for 1 hour. Photodarkening and thermal bleaching effects by laser irradiation and heat-treatment revealed reversible amorphous-to-amorphous transition varying only coordination number.