• Ocean and Polar Research
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• v.25 no.3
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• pp.249-256
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• 2003

An immunological method was developed in this study to quantify reproductive output of the female butter clam, Saxidomus purpuratus. A clam egg-specific polyclonal antibody was developed using the purified butter clam egg as an antigen. An indirect Enzyme-Linked Immunosorbent Assay (ELISA) was used in quantitative measurement of the eggs. Size of the butter clam eggs ranged from $70.81{\pm}7.52{\mu}m$ in histology or $88.56{\pm}11.31{\mu}m$ in intact eggs. The predominant egg constituent was protein (37.44%), followed by lipids (11.40%) and carbohydrates (9.68%). The SDS-PAGE showed that the egg proteins are composed of several peptides of molecular weights consisting of 247, 200, 99, 91, 54 and 47 kDa. ELISA indicated that the clams collected from Geoje Island in May 2002 produced 8.2 to 26.8% of their body weight as eggs or 9,307,309 to 31,156,333 with a mean of 16,931,893 eggs per individual clam. The results of this study thus suggest that indirect ELISA using rabbit anti-clam egg IgG as a primary antibody is a rapid, affordable and sensitive method to assess reproductive output of 5. purpuratus and possibly other bivalves using a small amount of eggs.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.759-765
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• 2004

The NCS inhibited the activity of glucosyltransferase which was produced by Streptococcus mutans JC-2, and the rate of inhibition at $100\muM<$ and $200\muM$ were 74.0% and 99.8%, respectively. It was stable in alkali condition, but unstable in acid condition. It was also stable up to $80^{\circ}C$. The kinetic study of the inhibition by NCS was carried out by Lineweaver-Burk plot and Dixon plot. It was non-competitive inhibition, determined by the two plots and $K_i$ and $K_i$ values were $15\muM$ and $19.3\muM$ respectively. The NCS did not show cytotoxicity against human gingival cells at $K_i$ ($15\muM$, $150\muM$, $1,500\mu$ M) concentrations. It had less cytotoxicity than chlohexidin, which has usually been used as the agent of anticaries. To evaluate the industrial applicability of the NCS, human pluck tooth was used. The inhibitory rates of tooth calcification and calcium ion elution by the NCS were 41 % and 2.5 times, respectively. These results suggested that NCS from Bacillus sp. S-1013 is an efficient anticaries agent.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.85-85
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• 1995

전년도에 ara-C 유도체 중에서 ara-CDP-DL-PTBA가 각종 암세포주에 대한 뛰어난 항암작용이 보고된바 있으며, 이후 시료의 대량확보, Bulk Formulation 및 전임상등의 세가지 분야에 관해 연구를 수행하였다. Ara-CDP-DL-PTBA를 수용액에 현탁, 초음파분쇄후 NICOMP Analysis에 의하여 micellar solution의 입자도를 알아 본 결과 fresh prepared micelles은 11,1mm size가 88.63%이며 50,5mm가 11.37%로 나타나 평균 19,0mm가 되고, Reconstructed micells은 10.9mm size가 99.87%이며 356.1mm가 0.13%로 나타나 평균 11.0mm가 된다. Ara-C와 Ara-CDP-DL-PTBA의 대사작용을 알아본 결과, ara-C는 투여 1시간째 2,850 $\pm$ 450 pmol, 4시간째 450$\pm$190 pmol, 24시간째 30 pmol 이하로 ara-CTP의 혈중 농도가 급격히 감소하는 반면에 ara-CDP-DL-PTBA는 1시간째 650$\pm$120 pmol, 2시간째 1,800$\pm$500 pmol, 24시간째 300$\pm$90 pmol으로 ara-CTP의 혈중 농도가 서서히 감소하였다.

• Korean Journal of Veterinary Research
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• v.33 no.2
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• pp.321-326
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• 1993

Sixty eight wild rats were caught from Seoul, Kyonggi, Kangwon, Cholla, and Kyongsang provinces in Korea. All of them were confirmed in the same species, Rattus norvigicus. All of sera from wild rats were examined by indirect immunofluorescent test against Hantaan-related virus. Detection of anti-body to Hantaan-related virus were 4 out of 68 rats(5.9%), including 2 of 8(25.0%) rats in Kangwon and 2 of 20 rats(10.0%) in Kyongsang province. No difference of the sero-positive rates between sex of rats tested to Hantaan-related virus was recognized. According to age, four rats with antibodies(1:320~640) to Hantaan-related virus belonged one subadult, one young adult, one middle aged adult, and one old adult, respectively.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.5
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• pp.34-39
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• 2003

The paper will present chip formation mechanism and surface integrity generation mechanism based on the systematical experimental tests. Some basic factors such as the end milling cutter tooth number, cutting forces, cutting temperature, cutting vibration the chip status, the surface roughness, the hardness distribution and the metallographic texture of the machined surface layer are involved. The chip formation mechanism is typical thermal plastic shear localization at high cutting speed with less number of shear ribbons and bigger shear angle than that at low speed, which means lack of chip deformation. The high cutting speed with much more cutting teeth will be beneficial to the reduction of cutting forces, enlarge machining stability mot depression of temperature increment anti-fatigability as well as surface roughness. The burrs always exist both at low cutting speed and at high cutting speed. So the deburring process should be arranged for milling titanium alloy in my case.

• Journal of Applied Reliability
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• v.17 no.2
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• pp.122-128
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• 2017

Purpose: To investigate the corrosion inhibition effect of the natural spearmint oil extracted from Mentha Spicata plants on 304 stainless steel in different concentrations of hydrochloric acid. Method: The anti-corrosive effect has been investigated in 0.5m, 1m and 2m HCl using weight loss test and electrochemical polarization method as a function of inhibitor concentration and immersion time in strong chloride environment. The surface morphology was analysed by scanning electron microscopy (SEM). Results: The corrosion rate of steel decreased and inhibition efficiency increased with the increase in inhibitor concentration. Microscopic evaluation revealed significant corrosion in the specimens immersed in uninhibited conditions. Potentiodynamic polarization test results showed an increase in corrosion potential (Ecorr) and decrease in corrosion current (icorr) value with increasing concentration of inhibitor. Conclusions: Immersion of steel in higher concentration of inhibitor resulted in greater surface coverage value and hence lesser number of surface corrosion sites/pores were formed; thus lowering the corrosion rate.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2631-2636
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• 2009

JHL45, a novel immune modulator for anti-atopic dermatitis and allergic airway disease, was synthesized from decursin isolated from Angelica gigas. In order to conduct a pharmacokinetic study of JHL45, an analytical method, ideally one that uses a minimal amount of biological sample must first be validated. In this study, a HPLC-MS/MS method was developed and validated for the quantification of JHL45 and its major metabolite, (+)-decursinol, from 10 ${\mu}L$ of rat plasma. JHL45 was stable under the analysis conditions, and intra- and inter-day accuracies exceeded 90.06%, with a precision variability ${\leq}$ 13.16% for each analyte. The mean values for Cmax, AUC8h, half-life of JHL45 in rats after intravenous administration of 5 mg/kg JHL45 were 24.59 μg/mL, 10.02 ${\mu}g{\cdot}h/mL$, and 1.88 h, respectively. The validated method herein will be useful for further pharmacokinetic studies of JHL45, as well as in preclinical and clinical phases.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.196-197
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• 2011

Rudder, one of the most important component in the marine vessel, is now being decreased life time to serve due to cavitation erosion, vortex current, high flow speed suffer from ship speed going up dramatically. In this study, 10 kinds of thermal spray coating materials(2 of Zn alloy series, 3 of Al alloy series, 3 of Cu alloy series, 2 of STS alloy series) are chosen to apply on specimens and analyze micro structure, metallic composition, properties(porosity, oxidation) by using visual observation, XRD, EDX etc.. Additionally, to refine the characteristic of corrosion endurance for thermal spray coating layer, compared with thermal spray process and 5 kinds of heavy duty painting and AC paint (Anti-Corrosion Paint). Based on above mentioned experimental results, a priority of all coated specimens on corrosion-erosion endurances finalized and summarized there by desirable composition and process of thermal sprayed material properly.

• Tunnel and Underground Space
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• v.20 no.5
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• pp.378-389
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• 2010

Submarine tunnels are affected by the surrounding environments more than regular tunnels. Especially, they are often vulnerable to damage by salt in seawater. Seawater is more likely to affect reinforcing rods and steel fibers than concrete. Recently the usage of anti-corrosive fibers increases in the tunnel which is subject to the possibility of damage. By comparing the capability of polypropylene fibers with that of steel fibers, the proper mixture ratio is decided and the supporting capability of polypropylene fibers was tested using round panel and beam specimens. The results of this study can be of great use in selecting the fiber material and designing of fiber reinforced shotcrete of submarine tunnels.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.3
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• pp.741-747
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• 2007

This study evaluated neuroprotective effects of Yanggyuksanhwa-tang (YST), which have been known to be efficacy in the treatment of the stroke and diabetes. on focal cerebral ischemia of diabetic rats. On primary experiment, diabetic condition in rats was induced by streptozotocin injection, then, focal cerebral ischemia was induced by the middle cerebral artery occlusion (MCAO) under the diabetic condition. Then neuroprotective effect of YST was observed with changes of infarct size and volume, expressions of c-Fos, Bax, and hypoxia inducible factor (HIF)-1${\alpha}$ in the brain tissues by using 2% 2,3,5-triphenyltetrazolium chloride (TTC) staining and immunohistochemistry. YST treatment showed a significant decrease of infarct size and volume induced by MCAO in diabetic rats. YST treatment showed a significant decrease of c-Fos and Bax positive neurons in cortex penumbra. YST treatment showed a decrease of HIF-l${\alpha}$ positive neurons in cortex penumbra, but it was not significant statistically. These results suggest that YST has effects on neuroprotection against cerebral infarct under diabetic condition. And it is supposed that neuroprotective effect of YST reveals by anti-apoptosis mechanism.