• Mycobiology
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• v.30 no.4
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• pp.183-192
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• 2002

Diversities of Korean species belonging to the genus Volvariella have been studied through forty five dried specimens collected throughout the Korean peninsula for 28 years, from 1972 to 2000, and preserved in NIAST's herbarium. We have found one unrecorded species of the genus Volvariella in Korea: V. villosavolva(Lloyd) Sing, Stirp Taylori Korean common names were designated. Ten species of the genus Volvariella including the recorded Korean species of Volvariella have been identified and the keys to the species were constructed.

• Natural Product Sciences
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• v.20 no.4
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• pp.274-280
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• 2014

Six compounds were isolated from the n-BuOH fraction of the aerial parts of Aruncus dioicus var. kamtschaticus including: sambunigrin (1), prunasin (2), aruncide A (3), aruncide C (4), 1-O-caffeoyl-${\beta}$-D-glucopyranose (5), and caffeic acid (6). Their structures were confirmed by comparing the spectral data with those reported in the literature. The isolated compounds (1 - 6) were then examined for their cytotoxic effects towards MCF-7, HL-60, and HeLa cancer cell lines, as well as their DPPH radical scavenging activity. The results indicated that compound 4 possessed the strongest inhibitory effect toward HeLa cell line with $IC_{50}$ value of $5.38{\pm}0.92{\mu}M$. Compound 3 possessed selective cytotoxic activity on HL-60 cells with $IC_{50}$ value of $6.27{\pm}0.17{\mu}M$, compound 5 was found as the best in inhibiting proliferation with $IC_{50}$ value of $2.25{\pm}0.09{\mu}M$, and the other compounds showed significant inhibition with $IC_{50}$ values ranging from 6.10 to $11.27{\mu}M$. Compound 5 also displayed the strongest cytotoxic effect toward MCF-7 cell line ($IC_{50}$ $4.32{\pm}0.15{\mu}M$). Both 5 and 6 demonstrated strong radical scavenging activity ($IC_{50}$ $6.87{\pm}0.03$ and $4.33{\pm}0.22{\mu}M$, respectively). Compounds 1 and 5 were isolated for the first time from this plant.

• Journal of Acupuncture Research
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• v.23 no.2
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• pp.103-111
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• 2006

Objectives : Deer antler Water Extract(DAE), prepared from the pilose antler of Cervus korean TEMMINCK var. mantchuricus Swinhoe (Nokyong), a traditional immuno-suppressive and immuno-activating Korean herbal-acupuncture, is thought to play an important role in human bone remodeling. Methods : To determine whether DAE can induce the differentiation of resting zone chondrocytes(RC) or not, confluent cell cultures were pretreated for 24, 36, 48, 72, and 120hrs with DAE. At the end of pretreatment, the media were replaced with new media containing $10^{-10}{\sim}10^{-8}M\;1,25-(OH)_2D_3$ and the cells incubated for an additional 24hrs. Results : This second treatment was chosen because prior studies had shown that only the more mature growth zone chondrocytes(GC) respond to this vitamin $D_3$ metabolite. The effect of DAE pretreatment on cell maturation was confirmed by measuring alkaline phosphatase (ALPase)-specific activity. Changes in matrix protein synthesis were examined by measuring collagen synthesis, as well as $^{35}SO_4$ incorporation into proteoglycans. When RC cells were pretreated for 120h with DAE, treatment with $1,25-(OH)_2D_3$ caused a dose-dependent increase in ALPase-specific activity and collagen synthesis, however, the proteoglycan production was not affected. RC cells pretreated with $1,25-(OH)_2D_3$ responded like RC cells that had not received any pretreatment. Conclusion : These results indicate that DAE directly regulates the maturation of RC chondrocytes into GC chondrocytes. Therefore it was indicated that DAE may play a significant role in regulating chondrocyte maturation during endochondral ossification.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.248-256
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• 2004

Dendropanax morbifera Lev.(Araliaceae), Korean endemic and evergreen small tree is a component of evergreen forest and mainly distributed in sourthern region and islands in Korea. The ecological characteristics of 4 natural stands of D. morbifera.(Sundol, Suak, Hannam, and Sangho populations in Cheju island) were studied. In most of the D. morbifera natural stands, the following tree species appeared predominantly: Castanopsis cuspidata var. sieboldii, Carpinus laxiflora, D. morbifera, Quercus glauca, Quercus myrsinaefolia, Camellia japonica, and Acer pseudo-sieboldianum. Two tree species, such as C. cuspidata var. sieboldii and C. laxiflora appeared in the all investigated stands. D. morbifera occupied 17.2% of the upper story, 12.9% of the middle story, and 10.3% of the lower story, respectively. The distribution patterns by Morisita' s Index showed that D. morbifera was distributed randomly in the three stories. The frequency distribution of DBH D. morbifera species showed reverse J-shaped, therefore it seems to remain as a dominant species.

• The Korean Journal of Ecology
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• v.15 no.4
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• pp.337-344
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• 1992

A study on the secondary succession and species diversity was conducted at burned sites of which pinus densiflora forest and its floor vegetation was almost destroyed by the forest first in the mts. todok, sansong and palgong from 1977 to 1986. The changes of vegetation during period the year to 11th after fire occurred miscanthus sinensis var. purpurascens $\rightarrow$ miscanthus sinensis var. purpurascens-lespedeza cyrtobotyra $\rightarrow$ lespedeza cyrtobotyra $\rightarrow$ lespedeza cyrtobotyra-quercus serrata community. The biological spectra based on $SDR_3$(%) and SP(%) were $H-D_1-R_5-e$ types. The species diversity generally decrease from miscanthus to lespedeza stage and reached minimum at stage of lespedeza, and after that a litter increase for lespedeza-quercus stage. The species distribution curves showed a decrease from miscanthus to lespedeza stage and slight increase at lespedeza-quercus stage in evenness.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.54 no.4
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• pp.179-184
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• 2005

This paper examines the application of high voltage static var compensator(SVC) with cascade multilevel inverter which employs H-bridge inverter(HBI). A new switching scheme is developed for the SVC system. To improve the unbalanced problem of the DC capacitor voltages, the rotated switching scheme of fundamental frequency is newly used. The optimized fundamental switching pattern with low switching frequency is adapted to be suitable for high application. The selective harmonic elimination method(SHEM) allows to keep the total harmonic distortion(THD) low in the output voltage of multilevel inverter. The SVC system is modeled using the d-q transform which calculates the instantaneous reactive power. This model is used to design a controller and analyze the SVC system. Simulated and experimental results are also presented and discussed to validate the proposed schemes.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.4
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• pp.172-178
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• 2003

This paper examines the application of high voltage static var compensator(SVC) with cascade multilevel inverter which employs H-bridge inverter(HBI). This method has the primary advantage that the number of voltage levels can be increased for a given number of semiconductor devices when compared to the conventional control methods. The SVC system is modeled using the d-q transform which calculates the instantaneous reactive power. This model is used to design a controller and analyze the SVC system. From the mathematical model of the system, the design procedures of the circuit parameters L and C are presented in this thesis. To meet the specific total harmonic distortion(THD) and ripple factor of the capacitor voltage, the circuit parameters L and C are designed. Simulated and experimental results are also presented and discussed to validate the proposed schemes.

• Research in Plant Disease
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• v.26 no.4
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• pp.272-278
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• 2020

The severe lettuce damage caused by Paratylenchus projectus was first reported in 2019 in Korea. To find high-value rotation crops for the control of P. projectus, nine vegetables, Brassica juncea (leaf mustard), B. rapa subsp. nipposinica (kyona), B. oleracea var. italica (broccoli), B. rapa subsp. chinensis (bok choy), B. oleracea var. viridis (kale), B. oleracea var. gongylodes (kohlrabi), Cichorium endivia (endive), C. intybus (chicory), Ipomoea aquatica (morning glory) were planted in d-10-cm clay pots in greenhouse. The growth of vegetables was compared between inoculated with 3,000 P. projectus per 100 ㎤ of soil and non-inoculated. Treatments were replicated 10 times. After 100 days, the reduction of fresh top weight was 30.4% in C. intybus, 35.1% in I. aquatica, 36.9% in B. oleracea var. acephala, 40.5% in C. endivia, 42.1% in B. rapa, 47.5% in B. rapa subsp. nipposinica, 50.4% in B. oleracea var. gonglodes, 56.3% in B. oleracea var. italica, and 66.0% in B. juncea. Nematode multiplication rates (Pf/Pi) were lower in I. aquatica (0.64) and C. endivia (1.1), but higher in B. oleracea var. gongylodes (2.54). Considering these results, I. aquatica is suitable for the rotation crop with lettuce until better rotation crops developed.

• Journal of Acupuncture Research
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• v.21 no.4
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• pp.225-236
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• 2004

본 실험에서는 녹용 약침액의 항 골재흡수 속성을 조사하였다. PTH, $1,25(OH)_2D_3$와 IL-1을 각각 골재흡수 인자로 사용하여 생쥐의 두개골에서 osteoblast 세포를 격리, 배양, 그리고 자극시켰을 때 collagenolysis의 증가를 보였다. 두 가지를 동시에 사용한 결과, IL-1은 골재흡수성을 촉진시키고 재 흡수력을 생산하였다. In vitro에서의 세포독성 결과는 $1-200{\mu}g/ml$의 녹용 약침액 농도 분포에서 무세포독성을 보였다. 또한 녹용 약침액은 생쥐의 두개골 골아세포 내에서 PTH (2 unit/ml), IL-$1{\alpha}$ (1 ng/ml), $1,25(OH)_2D_3$ (10 ng/ml), IL-$1{\alpha}$ 및 IL-$1{\beta}$로 인해 유발된 collagenolysis에 대해서 대항하는 보호활동성을 나타내었다. 녹용약침액은 IL-$1{\alpha}$ 와 IL-$1{\beta}$로 인해 유발된 collagenolysis에 대항하는 보호활동성을 지녔다. DAS는 IL-$1{\alpha}$와 IL-$1{\beta}$로 인해 촉진된 골재 흡수력을 억제하는 효과를 보였다. 이와 같은 결과는 녹용약침액이 골다공증과 연관된 질환에 대해서 매우 안정적인 임상적 사용이 가능한 것을 관찰할 수 있으므로 추후 이와 관련한 지속적인 연구가 필요할 것으로 사료되었다.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.318-321
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• 2002

To induce recombinant protein under phosphate restricted conditions such as soil, we have constructed the expression vector (pEAAP) with phoA gene promoter of Enterobacter aerogenes. To construct the pEAAP, deletion of the T7 promoter and lac operator from pET-22b(+) by BglII-XhoI digestion and addition of the phoA gene promoter (containing the pho box) were performed. To test pEAAP as an expression vector controled by phosphate limitation, pEAPHY1 was constructed with the phytate gene (Bsa-phy1) of Bacillus subtillis var. amyloliquefaciens (KCTC 8913P). Under the phosphate-limitation condition, CK-PHY1 ( Escherichia coli JM109 was transformed with pEAPHY1) expressed the 41 kD Bsa-Phy1 . Also CK-PHY1 formed the clear zone in solid medium containing phytate as a sole phosphate source.