• Corrosion Science and Technology
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• v.8 no.4
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• pp.162-169
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• 2009

Pure titanium and its alloys are drastically used in implant materials due to their excellent mechanical properties, high corrosion resistance and good biocompatibility. However, the widely used Ti-6Al-4V is found to release toxic ions (Al and V) into the body, leading to undesirable long-term effects. Ti-6Al-4V has much higher elastic modulus than cortical bone. Therefore, titanium alloys with low elastic modulus have been developed as biomaterials to minimize stress shielding. For this reason, Ti-30Ta-xZr alloy systems have been studied in this study. The Ti-30Ta containing Zr(5, 10 and 15 wt%) were 10 times melted to improve chemical homogeneity by using a vacuum furnace and then homogenized for 24 hrs at $1000^{\circ}C$. The specimens were cut and polished for corrosion test and Ti coating and then coated with TiN, respectively, by using DC magnetron sputtering method. The analyses of coated surface were carried out by field emission scanning electron microscope(FE-SEM). The electrochemical characteristics were examined using potentiodynamic (- 1500 mV~+ 2000 mV) and AC impedance spectroscopy(100 kHz~10 mHz) in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The equiaxed structure was changed to needle-like structure with increasing Zr content. The surface defects and structures were covered with TiN/Ti coated layer. From the polarization behavior in 0.9% NaCl solution, The corrosion current density of Ti-30Ta-xZr alloys decreased as Zr content increased, whereas, the corrosion potential of Ti-30Ta-xZr alloys increased as Zr content increased. The corrosion resistance of TiN/Ti-coated Ti-30Ta-xZr alloys were higher than that of the TiN-coated Ti-30Ta-xZr alloys. From the AC impedance in 0.9% NaCl solution, polarization resistance($R_p$) value of TiN/Ti coated Ti-30Ta-xZr alloys showed higher than that of TiN-coated Ti-30Ta-xZr alloys.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.69-75
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• 1998

Responses of tobacco(Nicotiana tabacum cv. Xanthi) leaves of different age to diphenyl ether herbicide oxyfluorfen were evaluated with respect to cellular leakage, chlorophyll loss, and membrane lipid peroxidation. When tobacco leaves of different age were incubated under light condition at $25^{\circ}C$ following 12hr dark incubation. Significant electrolyte leakage from the treated tissues into the bathing medium occurred. The change of electrolyte leakage was proportional to the oxytluorfen concentration and the duration of light exposure to the tissues. Electrolyte leakage from the tissues treated with oxyfluorfen was highly dependent on the leaf age. From the tissues of younger age, more electrolyte leakage occurred and lag period was greatly reduced. Chlorophyll loss and membrane lipid peroxidation, as measured by malondialdehyde production, caused by oxyfluorfen treatment were also dependent an the age of treated leaf tissues. In conclusion, physiological responses of tobacco leaves to oxyfluorfen greatly varied with the age of treated tissues, and thus tobacco plants could be used as appropriate materials for studying the mechanisms of tolerance to diphenyl ether herbicides.

• Journal of Life Science
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• v.20 no.3
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• pp.388-395
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• 2010

Cyclooxygenase (COX)-2 is generally known as an inducible enzyme, and it produces arachidonic acid to prostaglandin $E_2$ ($PGE_2$), which has been demonstrated to play a critical role in inflammation. In the present study, we investigated the effects of the extracts of fermented beans including soybean (FS), black agabean (FBA) and yellow agabean (FYA), on the expression of COXs and production of $PGE_2$ in U937 human promonocytic cells. Treatment of phorbol 12-myristate 13-acetate (PMA) significantly induced pro-inflammatory mediators such as COX-2 expression and $PGE_2$ production, whereas the levels of COX-1 remained unchanged. However, pre-treatment with FS, FBA and FYA significantly decreased PMA-induced COX-2 protein as well as mRNA, which is associated with inhibition of $PGE_2$ production. Moreover, FS, FBA and FYA markedly prevented the increase of nuclear translocation of nuclear factor kappa B (NF-${\kappa}B$) p65 by PMA. Our data indicate that the extracts of fermented beans exhibits anti-inflammatory properties by suppressing the transcription of pro-inflammatory cytokine genes through the NF-${\kappa}B$ signaling pathway.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.274-280
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• 2002

This study was conducted to investigate inhibitory effects of K-casein, GMP and sialic acid addition on the infection of MA-104 cells by 597(Korean native cattle rotavirus) and JBR(Jeju island bovine rotavirus). MA-104 cells on incomplete Ml99 were infected with domestically separated 597 and ma activated by incubating at 37$\^{C}$ for 6 days, and analyzed for the titer of rotavirus. K-casein, GMP and sialic acid added MA-104 culture infected by activated S97 and nan were incubated for Is hours and stained by the AEC stainning method. The number of infected cells were counted on microscope. The titer of S97 and JBR was 2.5$\times$107 and 2.0$\times$106 PFU/ml, respectively. The inhibition level against cell infection by 597 was 97.4% far 2000UH of K-casein and 97.44% for 2000UM of GMP. The inhibition level against cell infection by JBR was 99.52% for 2000$\mu$M of $\kappa$-casein and 99.78% for 2000$\mu$M of GMP. The inhibition level against cell infection by 597 and JBR was 3.85 and 3.63% for 2000$\mu$M of sialic acid, respectively. The high inhibitory effects (over 97%) of K-casein and CMP against infection of U-1(14 cells with 597 and mR indicated great potentials for the use of K-casein and GMP in the treatment of calf or infant caused by rotavirus.

• Korean Journal of Materials Research
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• v.3 no.5
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• pp.443-450
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• 1993

Self-alignment gatc Schottky contact structure on Si- implanted GaAs was formed by plasma enhanced chemical vapor dcposirion. Tungsten nitride thin films (ahclut 1600$\AA$) \vcre dopositcd on GaAs at $350^{\circ}C$ in order to fahricarc GaAs 1Cs and ttwn rapidly annealed at $750^{\circ}C$ to $900^{\circ}C$. Thermal charac tcristics of PECVD)-$W_{67}N_{43}$/GaAs structure were investigated by X-ray diffraction, photolumintesccnce. and optical deep level transient specrroscopy. Results revealed that $W_{67}N_{33}$ gate was more thermally sta ble with GaAs substrate than W gate and Si atoms implanted In $W_{67}N_{33}$/GaAs structure became morr active than those In W/GaAs after annealing. I-V characteristics of $W_{67}N_{33}$/GaAs diod c exhibired a nearly ideal diode behavior. The termal stability of $W_{67}N_{33}$/GaAs diode was better than that of W/GaAs diode with the post annealing at temperatures from 800 to $900^{\circ}C$ for 20s without As overpressure.

• The Korean Journal of Pain
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• v.27 no.3
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• pp.278-284
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• 2014

Background: Establishment of laparoscopic cholecystectomy as an outpatient procedure has accentuated the clinical importance of reducing early postoperative pain, as well as postoperative nausea and vomiting (PONV). We therefore planned to evaluate the role of a multimodal approach in attenuating these problems. Methods: One hundred and twenty adult patients of ASA physical status I and II and undergoing elective laparoscopic cholecystectomy were included in this prospective, randomized, placebo-controlled study. Patients were divided into four groups of 30 each to receive methylprednisolone 125 mg intravenously or etoricoxib 120 mg orally or a combination of methylprednisolone 125 mg intravenously and etoricoxib 120 mg orally or a placebo 1 hr prior to surgery. Patients were observed for postoperative pain, fentanyl consumption, PONV, fatigue and sedation, and respiratory depression. Results were analyzed by the ANOVA, a Chi square test, the Mann Whitney U test and by Fisher's exact test. P values of less than 0.05 were considered to be significant. Results: Postoperative pain and fentanyl consumption were significantly reduced by methylprednisolone, etoricoxib and their combination when compared with placebo (P<0.05). The methylprednisolone + etoricoxib combination caused a significant reduction in postoperative pain and fentanyl consumption as compared to methylprednisolone or etoricoxib alone (P<0.05); however, there was no significant difference between the methylprednisolone and etoricoxib groups (P>0.05). The methylprednisolone and methylprednisolone + etoricoxib combination significantly reduced the incidence and severity of PONV and fatigue as well as the total number of patients requiring an antiemetic treatment compared to the placebo and etoricoxib (P<0.05). Conclusions: A preoperative single-dose administration of a combination of methylprednisolone and etoricoxib reduces postoperative pain along with fentanyl consumption, PONV, antiemetic requirements and fatigue more effectively than methylprednisolone or etoricoxib alone or a placebo.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.249-257
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• 1991

To elucidate enzymatic properties of ${\alpha}-galactosidase$ (EC 3, 2, 1, 22) from germinated soybean, changes in the enzyme activities and oligosaccharide contents during germination of soybean were determined. ${\alpha}-Galactosidase$ from germinated soybean was purified by ammonium sulfate fractionation, ion exchange chromatography and gel filtration. Their chemical and enzymatic properties was investigated. ${\alpha}-galactosidase$ activity of sobeam was maximized when it was germinated at $25^{\circ}C$ for 120 hour. Raffinose and stachyose in soybean were decomposed completely after 96 hours and 120 hours of germination, respectively. Soybean ${\alpha}-galactosidase$ was purified by 6.6 fold by ammonium sulfate fractionation, ion exchange chromatography on DEAE-Cellulose and Sephadex A-50, and gel filtration on Sephadex G-150. Its specific activity was 825 Units/mg protein and the yield was 2.5% of the total activity of crude extracts. The purified ${\alpha}-galactosidase$ of soybean was found to be homogeneous by polyacrylamide gel electrophoresis and by HPLC. Isoelectric point of soybean ${\alpha}-galactosidase$ was determined analytical isoelectric focusing to be pH 4.8. The soybean ${\alpha}-galactosidase$ was monomeric and its molecular weight was estimated to be 30,000 by SDS-PAGE. The optimal temperature and pH for the soybeam ${\alpha}-galactosidase$ activity were $40^{\circ}C$ and pH 6.0 and 75% of its activity was lost by heating at $60^{\circ}C$ for 10 min. The enzyme was appeared to have higher affinity to raffinose than to stachyose. The Km value of soybean enzyme was 5.3 mM for ${\rho}-nitrophenyl-{\alpha}-D-galactopyranoside$ and the activation energy on PNPG was calculated to be 13.02 Kcal per mole.

• Journal of Distribution Science
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• v.16 no.8
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• pp.63-68
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• 2018

Purpose - Lettuce (Lactuca sativ L.) is one of the economically important vegetable crops, which worldwide market value is over 100 billion U.S. dollar. In Korea, about 89.7 kilo ton of lettuce was produced in 3400ha in 2016, recoded as No. 1 vegetable crop in domestic green house production. However, recently, domestic lettuce production and cultivation areas are all getting decreased. Thus, novel approaches are needed to be implemented to revive the production. Research design, data and methodology - In this review paper, we first prioritized the end-user traits which are imperative to positively stimulate the domestic lettuce market and discussed relevant genomics strategies. Especially, we assessed a possibility whether school meal program would be a potential niche market. Results - The genomics technologies, which become widely applied in the crop biotechnology since 2008 when next generation sequencing method was developed, may be a good solution in the crop improvement, efficiently gathering valuable information of agriculturally useful traits. Significantly, in lettuce, the high quality whole genome sequence, based on Lactuca sativa cv. Salinas, is publically available and this genomics platform, thus, would be implemented in lettuce breeding program to innovate relevant end-user traits both for the farmers and customers, including the disease resistance to the Fusarium wilt, productivity under hot weather conditions, various nutritional qualities and so forth. These improvements will boost domestic lettuce industries in the near future. Conclusions - Due to the nutritional distinctions comparing to the western style lettuces, domestic leaf lettuces could be one of the important vegetables in the school meal programs. To make it happen, we would better devise diverse recipes to make a salad with it, instead of only using as a wrap vegetable. Meanwhile, novel lettuce varieties need to be developed, which are favorable to the students and also easy to be handled with while processing. Overall, to achieve international competence in the lettuce industries, we need to create elite lettuce varieties that satisfies domestic farmers as well as customers, suitable to various niche markets, such as school meal program. Thus, efficient breeding programs using genomics approaches should be established in advance and careful monitoring on the preference of the related customers for a niche market be continued persistently.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.138-144
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• 2005

This in vitro study monitored MMP-8 production on PMN by stimulated with the following three groups; Sonicated extracts of E. faecalis (SEF), SEF treated with $Ca(OH)_2$ (12.5mg/ml) for 7 days, and lipopolysac-charides(LPS) of E. coli. The level of MMP-8 in each group was immediately measured by ELISA. The data were analyzed with Kruskal-Wallis test and Mann-Whitney U test. In the SEF group, the level of production of MMP-8 was higher than the negative control group in low concentration ($0.05{\mu}g/ml$) of SEF (p < 0.05). but it decreased with an increase in the concentration of SEF (p < 0.05). In the case of SEF treated with $Ca(OH)_2$, all of the MMP levels were higher than negative control group (p < 0.05), but no statistical difference was found among the different SEF concentrations (p > 0.05). All of the levels in E. coli LPS were incresed with increasing concentrations (p < 0.05). According to this study we could summarized as follows: 1. MMP-8 was expressed at low level in untreated PMN group the levels of MMP-8 were upregulated in PMN stimulated by E. coli LPS groups. 2. In the SEF groups, the level of production of MMP-8 decreased with an increase in concentration of SEF (p < 0.05). So E. faecalis may have suppressive effect on the production of MMP-8 by PMN. 3. In the case of SEF treated with $Ca(OH)_2$, all of the MMP levels at different SEF concentrations were higher than untreated PMN group (p < 0.05), but no statistical difference was found among the different SEF concentrations (p > 0.05).

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.994-1005
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• 2016

Expansion and spreading of marine telemedicine is rather restricted due to the conflict of laws relating to medical service and lack of provisions in the Seafarers' Act, Medical Service Act, etc. Thus, this study is intended to reveal the current status and problems of marine emergency medical advice system for the furtherance of health care of seafarers and emergency medical assistance conditions and deduce relevant proposals for legislative improvements thereof in order to resolve underlying problems and issues. The results of this study can be summated as follows. First, in respect of directions to provide marine emergency service based on marine telemedicine system, emergency radio medical advice system needs to be strengthened to meet domestic and international instrument, marine telemedicine system needs to be provided through integrating u-Health technology and special marine medical center needs to be established. Second, regarding directions to provide health promotion service based on the marine telemedicine system, a new process of health care service for seafarers needs to be devised and provided involving seafarers' life cycle covering from prior to boarding to after leaving a ship. The conclusions of this study can be given as follows. First, the following new provisions need to be introduced in the Seafarers' Act. (1) The Minister of Oceans and Fisheries and a shipowner shall conduct matters pertaining to preventive health promotion and care for seafarers; (2) a provisions regarding establishment of seafarers' health promotion center by the Minister; (3) a special exemption permitting marine telemedicine service and qualification requirements for marine telemedicine assistant; (4) shipowner's obligation of carrying seafarers' health measuring equipment on board. Second, the relevant provisions regarding medical care persons needs to be revised in such a way that master or chief officer shall be appointed to be in charge of medical care on board. Last but not least, it is also essential to amend and update the minimum standards on drug and medicines to be carried on board and medicine chest and equipment on board.