• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.98-103
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• 1992

The dynamic and static torque characteristics of a three dimensional control panel installed behind a guide panel were investigated in a wind tunnel. The panel was tested for various wind speeds, angles of attack and positions of the panel. The effects of the rotational speed and the amplitude of the sinusoidal motion were also studied. The increasing rate of torque coefficients with the angular position of the panel is small when the panel remains in the wake region, but is linear when it reaches the external stream. In case of a sinusoidal motion of the pannel, a hysterisis appears in the dynamic torque. The hysterisis becomes strong as the wind speed and the angular speed of the panel increase. The unsteady torque is considered quasi-steady when the angular speed is less than 5.5rad/s, i.e. the reduced frequency is less than 0.035.

• Korean Journal of Plant Taxonomy
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• v.47 no.2
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• pp.100-105
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• 2017

A new species, Epilobium ulleungensis J. M. Chung (Onagraceae Juss), from Ulleungdo Island (South Korea) was described and illustrated. Among four taxa native to Ulleungdo Island (E. amurense Hausskn. subsp. cephalostigma (Hausskn.) C. J. Chen, Hock & P. H. Raven, E. hirsutum L., E. pyrricholophum Franch. Sav., and E. ulleungensis), E. ulleungensis has a unique tetragonal stigma, which is considered to be an intermediate form between clavate (E. pyrricholophum) or capitate (E. amurense subsp. cephalostigma) and 4-lobed stigmas (E. hirsutum). More importantly, this new species is clearly distinguished from the other three taxa distributed on Ulleungdo Island by its height (over 200 cm), decumbent stem, leaf shape, short, dense pubescent covering on the whole plant, large flower size, and a dark pink or red purple flower. According to the stigma shape and other characters, it was estimated that E. ulleungensis is a hybrid between E. hirsutum and E. pyrricholophum or E. amurense subsp. cephalostigma). The specific epithet "ulleungensis" was chosen because the new species was restricted to Ulleungdo Island.

• Korean Journal of Plant Resources
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• v.20 no.3
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• pp.234-241
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• 2007

The present study was undertaken to classify and describe the riparian vegetation of the 6 river${\cdot}$stream of Korea Peninsula. As a result the vegetation was divided into nineteen communities. The vegetation units obtained in the present study were as follow: A: Salix koreensis community, B: Salix gracilistyla community, C: Robinia pseudo-acacia community, D: Amorpha fluticosa community, E: Brousonnetia papyrifera community, F: Phyllostachys bambusoides community, G: Rubus corchorifolius community, H: Phramities japonica community, I: Phramites communis community, J: Miscanthus sacchariflorus community, K: Miscanthus sinesis var. purpurascens community, L: Artemisia princeps var. orientalis community, M: Humulus japonicus community, N: Zoysia japonica community, O: Inperata cylindrica var. koenigii community, P: Agropyron tsukushiense var. transiens community, Q: Juncos effusus var. decipiens community, R: Rumex crispus community, S: Persicaria hydropiper community. The vegetation characteristics of riversides was recovered in the surveyed results according to river${\cdot}$stream basin, in other words, 10 communities in the upper river${\cdot}$stream riparian, 15 communities in the middle river${\cdot}$stream riparian, 10 communities in the down river${\cdot}$stream riparian. The Phragmites japonica community in the upper and Phragmites communis community in the down was analyzed by common community of the 6 river${\cdot}$stream riparian, respectively, but none in the middle. The standing profile of vegetation across 6 river${\cdot}$stream was seen stepwise Phragmites japonica community, Salix gracilistyla community, Miscanthus sinensis var. purpurascens community, shrub community by natural waterway in the upper, Salix gracilistyla community, Phragmites communis community, Rumex crispus community, Miscanthus sacchariflorus community, Humulus japonicus community in the middle, Phragmites communis community in the down. The differences of distributional featurs of vegetation emerged from the riparian of the 6 river${\cdot}$stream, but don't from the 6 river${\cdot}$stream.

• Journal of Korea Foresty Energy
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• v.21 no.3
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• pp.1-9
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• 2002

Various types of acids, such as mineral acids, organic acids, and organic sulfonic acids, were used as catalysts in order to investigate their effectiveness during phenol liquefaction of pine bark. Hydrochloric arid was the most effective acid catalyst of the mineral acids used in this experiment for the phenol liquefaction, but the amount of the acid needed for more than 90% liquefaction was at least 11 mmol. Among the carboxylic acids used triflouroacetic acid (TFA) was effective for the liquefaction, but it was not possible to obtain liquefaction of more than 80%. Organic sulfonic acids, p-toluenesulfonic acid (PTSA) and methanesulfonic acid (MSA), showed remarkable effects for liquefaction, even in small amounts and at low liquefaction temperatures. Especially in the case of PTSA, a 92% liquefaction yield was obtained at the liquefaction condition of 14$0^{\circ}C$ for 2 h. Therefore, it was evident that the PTSA is a good acid catalyst for the phenol-pine bark liquefaction system.

• Advances in Traditional Medicine
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• v.9 no.2
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• pp.106-114
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• 2009

Hepatocellular carcinoma is the world's most common primary malignant tumor of the liver. In-Jin-ho-Tang (IJHT) has been used as a traditional Chinese herbal medicine since ancient times, and today it is widely used as a medication for jaundice associated with inflammation of the liver. In-Jin-Ho-Tang is a drug preparation consisting of three herbs: Artemisiae Capillaris Herba (Artemisia capillaries $T_{HUNS}$, Injinho in Korean), Gardeniae Fructus (Gardenia jasminodes $E_{LLIS}$, Chija in Korean) and Rhei radix et rhizoma (Rheum palmatum L., Daehwang in Korean). This study investigated whether or not methanol extract of IJHT could induce HepG2 cancer cell death. Cytotoxic activity of IJHT on HepG2 cells was measured using an XTT assay, with an $IC_{50}$ value of $700{\mu}g/ml$ at 24 h Apoptosis induction by IJHT in HepG2 cells was verified by the cleavage of poly ADP-ribose polymerase, and a decrease in procaspase-3, -8, -9. Treatment of IJHT resulted in the release of cytochrome c into cytosol, loss of mitochondrial membrane potential (${\Delta}{\Psi}_m$), decrease in anti-apoptotic Bcl-2, and an increase in pro-apoptotic Bax expression. Thus, IJHT induced apoptosis in HepG2 cells via activation of caspase and mitochondria pathway. These results indicate that IJHT has potential as an anti-cancer agent.

• Mycobiology
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• v.38 no.2
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• pp.89-96
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• 2010

This study evaluated the optimal vegetative growth conditions and molecular phylogenetic relationships of eleven strains of Agrocybe cylindracea collected from different ecological regions of Korea, China and Taiwan. The optimal temperature and pH for mycelial growth were observed at $25^{\circ}C$ and 6. Potato dextrose agar and Hennerberg were the favorable media for vegetative growth, whereas glucose tryptone was unfavorable. Dextrin, maltose, and fructose were the most effective carbon sources. The most suitable nitrogen sources were arginine and glycine, whereas methionine, alanine, histidine, and urea were least effective for the mycelial propagation of A. cylindracea. The internal transcribed spacer (ITS) regions of rDNA were amplified using PCR. The sequence of ITS2 was more variable than that of ITS1, while the 5.8S sequences were identical. The reciprocal homologies of the ITS sequences ranged from 98 to 100%. The strains were also analyzed by random amplification of polymorphic DNA (RAPD) using 20 arbitrary primers. Fifteen primers efficiently amplified the genomic DNA. The average number of polymorphic bands observed per primer was 3.8. The numbers of amplified bands varied based on the primers and strains, with polymorphic fragments ranging from 0.1 to 2.9 kb. The results of RAPD analysis were similar to the ITS region sequences. The results revealed that RAPD and ITS techniques were well suited for detecting the genetic diversity of all A. cylindracea strains tested.

• Macromolecular Research
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• v.13 no.4
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• pp.285-292
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• 2005

We developed alginate beads loaded with transforming growth $factor-{\beta}_{1}(TGF-{\beta}_{1})$ to examine the possible application of the scaffold and cytokine carrier in tissue engineering. In this study, bone marrow stromal cells (BMSCs) and $TGF{\beta}_{1}$ were uniformly encapsulated in the alginate beads and then cultured in vitro. The cell morphology and shape of the alginate beads were observed using inverted microscope, scanning electron microscope (SEM), histological staining and RT-PCR to confirm chondrogenic differentiation. The amount of the $TGF{\beta}_{1}$ released from the $TGF-{\beta}_{1}$ loaded alginate beads was analyzed for 28 days in vitro in a phosphate buffered saline (pH 7.4) at $37^{\circ}C$. We observed the release profile of $TGF-{\beta}_{1}$ from $TGF-{\beta}_{1}$ loaded alginate beads with a sustained release pattern for 35 days. Microscopic observation showed the open cell pore structure and abundant cells with a round morphology in the alginate beads. In addition, histology and RT-PCR results revealed the evidence of chondrogenic differentiation in the beads. In conclusion, these results confirmed that $TGF-{\beta}_{1}$ loaded alginate beads provide excellent conditions for chondrogenic differentiation.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.428-433
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• 2017

Background: In this study, the fermentation of ginseng seeds was hypothesized to produce useful physiologically-active substances, similar to that observed for fermented ginseng root. Ginseng seed was fermented using Bacillus, Pediococcus, and Lactobacillus strains to extract ginseng seed oil, and the extraction yield, color, and quantity of phenolic compounds, fatty acids, and phytosterol were then analyzed. Methods: The ginseng seed was fermented inoculating 1% of each strain on sterilized ginseng seeds and incubating the seeds at $30^{\circ}C$ for 24 h. Oil was extracted from the fermented ginseng seeds using compression extraction, solvent extraction, and supercritical fluid extraction. Results and Conclusion: The color of the fermented ginseng seed oil did not differ greatly according to the fermentation or extraction method. The highest phenolic compound content recovered with the use of supercritical fluid extraction combined with fermentation using the Bacillus subtilis Korea Food Research Institute (KFRI) 1127 strain. The fatty acid composition did not differ greatly according to fermentation strain and extraction method. The phytosterol content of ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method was highest at 983.58 mg/100 g. Therefore, our results suggested that the ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method can yield a higher content of bioactive ingredients, such as phenolics, and phytosterols, without impacting the color or fatty acid composition of the product.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.15-15
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• 1991

한국어 자음에 대한 생리적인 분류는 조음점 및 조음발법에 따라 다시 세분화할 수 있는데 그중에서 조음발법에 따라 파열음, 마찰음, 파찰음 및 비음들 여러가지로 분류할 수 있다. 그중 특히 파열음은 그 개방하는 방법에 따라 연음(lenis), 경음(glottalized) 및 기식음(aspirated)등으로 구분하는데 이러한 각음을 육안으로 확인하면 모음이 발성되기 위한 성대진동이 있기전의 자음을 위한 성대의 운동의 현상을 보면 기식음에서는 성대열림이 가장 크고 연음에서도 열림이 크지만 기식음보다는 적고 경음에서는 성대의 열림이 가장 작았다. 이러한 현상은 후두내시경에 의해 쉽게 확인할 수 있었는데 이것을 과학적으로 규명하기 위해서는 여러연구에 의해 가능하나 흔히 후두근전도 검사에 의한 성대내전근과 외전근의 역할의 차이를 비교함으로서 가능해지리라 예상되어 본 연구를 시행하였다. 사용된 문형 또는 단어는 한가지를 제외하고는 모두 의미있는 단어를 사용하였으며 EMG recording을 위해 사용된 근육은 후두내전근인 Vocalis muscle과 후두외전근인 Posterior cricoarytenoid muscle이 사용되었고 전기신호는 computer data processing system에 의해 분석되어졌다. 결과는 내시경에 의한 성대열림의 거리측정 결과를 분석함과 동시에 후두내근에 대한 근전도검사에 의한 분석을 토대로 하였으며 이를 간단히 설명하면 이제까지 많은 사람들은 한국어 자음에 대한 각각의 특징적인 현상들을 주로 성대내전근의 역할에 의해 규명하였으나 본 결과로는 성대내전근의 역할도 중요하지만 성대외전근의 역할 또한 상호 연관성을 가지면서 매우 중요한 역할을 한다는 점이다.for the Isotropic plates can be used. Use of some coefficients can produce "exact" value for laminates with such configuration.trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of carriers from the shallo

• Animal cells and systems
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• v.9 no.3
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• pp.139-144
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• 2005

The attractant (orange light) or repellent (white light) signal is transmitted from SRI (Sensory Rhodopsin I) via protein-protein interaction with its transducer Htrl (Halobacterial Transducer for Sensory Rhodopsin I) which in turn controls a cytoplasmic phospho-transfer pathway that modulates flagella motor switching in Halobacterium salinarum. Some mutations in both SRI and Htrl showed an unusual mutant phenotype called inverted signaling, in which the cell produces a repellent response to normally attractant light. Twelve mutations at the Glutamate 56 (E56) position in the second transmembrane helix of Htrl were introduced by site-specific random mutagenesis. Almost all E56 mutants showed orange-light inverted responses in pH and temperature-dependent manners except E56D and E56Y. Except for these two mutants, all mutants accelerated the $S_{373}$ decay compared to wild-type at $18^{\circ}C$. This supported that there is an interaction between SRI and the second transmembrane of Htrl. Also a structural model of Htrl based on the Tar crystal structure and the secondary structure prediction program proposed the E56 residue to be in the middle of the proton channel. The most important observation is that the E56 mutant provides the evidence that this residue is very sensitive for signal relay, which can be explained by the open and closed conformations of the channel (A and R conformations) in SRI, as was postulated by the unified conformational shuttling model for transport and signaling.