• Journal of Life Science
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• v.29 no.3
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• pp.369-375
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• 2019

Microtubules form through the polymerization of ${\alpha}-$ and ${\beta}-tubulin$, and tubulin transport plays an important role in defining the rate of microtubule growth inside cellular appendages, such as the cilia and flagella. Heterotrimeric kinesin 2 is a molecular motor member of the kinesin superfamily (KIF) that moves along the microtubules to transport multiple cargoes. It consists of two motor subunits (KIF3A and KIF3B) and a kinesin-associated protein 3 (KAP3), forming a heterotrimeric complex. Heterotrimeric kinesin 2 interacts with many different binding proteins through the cargo-binding domains of the KIF3s, but these binding proteins have not yet been specified. To identify these proteins for KIF3A, we performed yeast two-hybrid (Y2H) screening and found a specific interaction with ${\beta}2-tubulin$ (Tubb2), a microtubule component. Tubb2 was found to bind to the cargo-binding domain of KIF3A but did not interact with KIF3B, KIF5B, or kinesin light chain 1 in the Y2H assay. The carboxyl-terminal region of Tubb2 is essential for interaction with KIF3A. Other Tubb isoforms, including Tubb1, Tubb3, Tubb4, and Tubb5, also interacted with KIF3A in the Y2H screening. However, ${\alpha}1-tubulin$ (Tuba1) did not interact with KIF3A. In addition, an antibody to KIF3A specifically co-immunoprecipitated the KIF3B and KAP3 associated with Tubb2 from mouse brain extracts. In combination, these results suggest that a heterotrimeric kinesin 2 motor protein is capable of binding to tubulin and may transport it in cells.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1619-1624
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• 2014

A new series of carbazole based 2,4-disubstituted thiazole derivatives were synthesized. All the synthesized compounds were tested for their cytotoxicity against three different cancer cell lines A549, MCF-7, and HT29. Some of these compounds showed good cytotoxicity. These compounds were also evaluated for antioxidant activity. Compounds 3a, 3b, 3d-f and 3i showed higher antioxidant activity than standard BHT.

• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.193-200
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• 2000

Si$_3$N$_4$powder with 2 wt% $Al_2$O$_3$and 6 wt% $Y_2$O$_3$additives was sintered by the gas pressure sintering (GPS) technique. The unlubricated wear behavior depending on sintering conditions such as sintering temperature, pressure, and sintering time was investigated. When the sintering temperature and time increased, the larger elongated grains were formed and the microstructural heterogeneity increased. When sintering pressure increased, grain growth, however, was impeded. Also, the wear properties depended on microstructure and friction coefficient were related to grain size. Based on the experimental results, the wear properties were associated with initial friction coefficients as well as mechanical properties including fracture toughness and flexural strength.

• Journal of Preventive Medicine and Public Health
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• v.4 no.1
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• pp.31-34
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• 1971

This study was conducted by the Dept. of Preventive Medicine, Kyung Hee University, School of Medicine as a preliminary test for the effects of Fluorine Compounds to the Plants from April through August, 1971. Fluorine was measured with Zirconium-Alizarine method and the following findings could be obtained: 1. Most high densities (25.7 pptm) was found around the industrial areas and lowest (19.3 pptm) around residential sections in Seoul. 2. Average density of Fluorine in the atmosphere of Seoul City was 22.3 pptm which can damage such plants as Pine, Strawberry, Peach and Grapes. 3. Fluorine contents (22.3 pptin) in Seoul area atmosphere shows about 4 times more than that of Cincinnati, Ohio, U. S. A.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.336-340
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• 2004

In order to search for anti -melanin formation agents from Korean medicinal herbs, we selected 21 Korean medicinal herbs, based on a review of Korean traditional medicine books and the recommendations of Korean traditional medical doctors. We tested for inhibition effect of melanin pigmentation of Clone M-3 mouse melanocyte cell lines when we treated the extracts of 21 medicinal herbs in the mouse melanocyte cell lines, respectively. Among 21 medicinal herb extracts, 5 extracts showed a inhibition effect of melanin formation. The sample Phaseolus radiatus L, Cordyceps militaris, Pinellia ternata, Phellinus linteus and Citrus junos Tanaka showed a significantly little formation of melanin pigments compared with control groups. Especially extract of Citrus junos Tanaka was more potent than the others. These results suggest that extract of Korean Citrus junos may represents an excellent candidate for inhibition of melanin pigmentation at in vitro level.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.458-463
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• 1997

A transient natural circulation behavior during a LOCA at hot-standby operation is evaluated for YGN Units 3/4. The plant initial condition is determined within the EOP limitation as suitable to hot-standby mode and the transient scenario is prepared as relevant to evaluation of transient natural circulation. A 0.4% cold leg break with loss of off-site power is calculated with RELAP5/MOD3.2, whose predictability has been verified for SBLOCA natural circulation test, S-NC-8B. Through one hour transient analysis, it is found that the plant has its own decay heat removal capability by natural circulation following a LOCA, at hot-standby mode. Additional calculation is performed to investigate an effect of HPSI flow on natural circulation.

• Carbon letters
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• v.15 no.3
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• pp.162-170
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• 2014

Pitch is an attractive raw material for carbon fiber precursors due to its low cost stemming from its availability as a residue of coking and petroleum processes. Ford Motor Company reported a carbon fiber target price of $11.0/kg by using a fast cycle-time manufacturing method with carbon fiber in an inexpensive format, allowing for an average retail price of gasoline of $3.58/gallon. They also recommended the use of carbon fiber with strength of 1700 MPa, modulus of 170 GPa, and 1.5% elongation. This study introduced a ca. $5.5{\mu}m$ carbon fiber with 2000 MPa tensile strength obtained from a precursor through simple distillation of petroleum residue. Petroleum pitch based carbon nanofibers prepared via electrospinning were characterized and potential applications were introduced on the basis of their large specific surface area and relatively high electrical conductivity.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.83-88
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• 2004

In order to investigate whether or not CCD-980sk cell line can be affected by Korean Citrus junos and medicinal herbs, we examined the MTT assay when we treated Korean Citrus junos and medicinal herbs in CCD-986sk human fibroblast cell line. The samples that added complex of grinded extracts of Korean Citrus junos and boiling-water extracts from Korean medicinal herbs were tested toy cell proliferation activity by means of a modification of the MTT assay. Among mixture of Citron 3 (Citron 3, less mellowed citron which was ripened for three months) and boiling-water extracts, the group Citron 3+Phellinus linteus showed significantly strong cell proliferation activity. And among mixture of Citron 4 (Citron 4, completely mellowed citron which was ripened for four months) and boiling-water extracts, the group Citron 4＋Cordyceps militaris and Citron 4+Phellinus linteus showed significantly strong cell proliferation activity, respectively. These results suggest that complex of Korean Citrus junos and medicinal herbs could be an excellent candidate toy protection of human skin aging.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.269-273
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• 1997

This research aims at developing a new plant growth inhibitors related to abscisic acid by means of esterification of (S)-(+)-ABA with p-hydroxy methyl cinnamate and umbelliferone, and testing its biological activity on growth of rice seedlings. The over-all yield of ABA-methyl cinnamate(AC) and ABA-umbelliferone(AC) ester compounds were 83% and 78%, respectively. The growth inhibition activity of these synthetic compounds were shown about 3 to 10 times(AC) and 10 to 30 times(AU) higher than (S)-(+)-ABA.

• The Korean Journal of Ceramics
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• v.3 no.1
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• pp.24-28
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• 1997

Diamond deposition by muti-cathode DC PACVD has been investigated. Five cathodes were independently connected to their own DC power supplies. The voltage and current of each cathods were varied up to 700 V and 3.5 A, respectively. The plasma formation and the diamond deposition behaviour on a substrate of 3 inch in diameter were investigated by optical emission spectroscopy, SEM and Raman spectroscopy. The plasma formed by five cathodes was non-uniform, which was depended on the geometry of cathods array. The growth rate and the quality of diamond film were closely related to the spatial distribution of the plasma.