• Ocean and Polar Research
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• v.41 no.4
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• pp.265-274
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• 2019

To trace the provenance of fine-grained sediments in response to the growth and retreat of glaciers (i.e., Ross Ice Sheet) that affects the depositional process, various kinds of analyses including magnetic susceptibility, granulometry, and clay mineral composition with AMS ¹⁴C age dating were carried out using a gravity core KI-13-GC2 obtained from the Central Basin of the Ross Sea continental margin. The sediments mostly consist of silty mud to sand with ice-rafted debris, the sediment colors alternate repeatedly between light brown and gray, and the sedimentary structures are almost bioturbated with some faint laminations. Among the fine-grained clay mineral compositions, illite is highest (59.1-76.2%), followed by chlorite (12.4-21.4%), kaolinite (4.1-11.6%), and smectite (1.2-22.6%). Illite and chlorite originated from the Transantarctic mountains (metamorphic rocks and granitic rocks) situated to the south of the Ross Sea. Kaolinite might be supplied from the sedimentary rocks of Antarctic continent underneath the ice sheet. The provenance of smectite was considered as McMurdo volcanic group around the Victoria Land in the western part of the Ross Sea. Chlorite content was higher and smectite content was lower during the glacial periods, although illite and kaolinite contents are almost consistent between the glacial and interglacial periods. The glacial increase of chlorite content may be due to more supply of the reworked continental shelf sediments deposited during the interglacial periods to the Central Basin. On the contrary, the glacial decrease of smectite content may be attributed to less transport from the McMurdo volcanic group to the Central Basin due to the advanced ice sheet. Although the source areas of the clay minerals in the Central Basin have not changed significantly between the interglacial and glacial periods, the transport pathways and delivery mechanism of the clay minerals were different between the glacial and interglacial periods in response to the growth and retreat of Ross Ice Sheet in the Ross Sea.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.102-107
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• 1983

The effects of saponin, one of major components (Panax ginseng C.A. Meyer), on the growth of E. coli K-12 and the formation of siderphore was observed The following results were obtained. 1. When E. coli was grown on medium containing 1${\times}$10-5%-11${\times}$10-1% of the saponin, the rate of growth was stimulated at 10-1% of the saponin significantly compared to that of control. 2. When E. coli K-12 was grown on medium containing 1${\times}$10-1% of the saponin, the amount of siderphore was two times as much as the control. 3. The growth of E. coli was observed to be dependent on the concentration of siderophore when siderophore was added to medium. 4. The effect of saponin on the formation of siderophore in vitro was observed to reach maximum at 1${\times}$10-3% of the saponin. Such results suggest that the growth rate of E. coli K-12 could be enhanced by ginseng saponin fraction through stimulation of siderphore formation. We have described the fast growth of E. coli, K-12 and B. subtilis, rapid uptake of 14C-glucose, and high level of other metabolites such as lipids and proteins of E. coli, and B. subtilis in medium containing saponing fraction compared to that of microorganisms without saponin fraction.1∼3Such differences were claimed to be due to rapid uptake of 14C-glucose by widened periplasmic region throught unknown mechanism in the prescence of saponin fraction in medium3 and have raised a question whether there is another possible factor, siderophore4(Greek for iron bears), since microorganisms must secure a sufficient amount of iron for normal growth. These are known to be synthesized by the cells under iron-deficient condition and in most case, excreted into the medium5, where they can complex and solubilize any iron present there. It is generally believed that these complexes are then taken into the cells presumably by specific transport systems, thus providing iron for cell metabolism. Within the group of enteric bacteria, only three species (E. coli, S. typhimurium, and A. aerogense) have, so far, been studied in a ny detail. The main iron-binding compound produced by these species is enterochelin, and its role in iron transport is now well established. And biosynthesis of enterochelin from 2, 3- dihydroxybenzoate and serine in the prescence of magnesium ions and ATP was reported6. 2, 3-dihydroxybenzoate was also shown to involve isochorismate and 2, 3-dihydro-2, 3-dihydroxybenzoate as intermediate.7∼11 The present paper deals with the effect of ginseng saponin fraction on growth, the level of enterochelin formation in vivo and the conversion of 2, 3-dihydroxybenzoate and serine into entrochelin in vitro, and entrochelin obtained on the growth in relation to possible explanation of ginseng saponin fraction on the rapid growth of E. coli, K-12.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.29 no.3
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• pp.27-41
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• 2016

Objectives : The purpose of this research is to understand melanin with both Korean and Western medicine.Methods : We investigated the comprehension of melanin in both western and Korean medicine through literature review and studied relationships between melanin and five viscera(五臟), especially liver(肝), spleen(脾), kidney(腎). We Also studied representative pigmentary disorders(melasma, vitiligo) in western and Korean medicine to figure out how to understand pigmentary disorders in oriental medicine.Results : The results are as follows. 1. Melanin is associate with liver, because free coursing(疎泄) function of liver is the origin of transport melanin to keratinocyte from melanocyte. Also, melanogenesis factors like MITF and CREB are closely associated with liver and pigmentary disorders occur frequently after stress conditions or women. 2. Melanin is absorbed and scattered in keratinocytes by the function of spleen. Pigmentary disorders result from failure of spleen and formation of phlegm-retained fluid(痰飮). 3. Kidney essence(腎精) is the origin of melanin formation. In addition, corticosteroid, the major hormone of melanogenesis is secreted by adrenalin and adrenalin belongs to kidney(腎) in Korean medicine. 4. Melasma is created by disorder of melanin transport and absorbtion, so melasma is associated liver (肝) and spleen(脾). Therefore the treatment for melasma may focus on improvement function of liver and spleen. 5. The destruction of melanocyte or abnormal melanogenesis by disorder of the immune system, metabolic and affective disorders can make vitiligo, so vitiligo is associated with liver and kidney which are major part of melanin formation. Therefore the treatment of vitiligo can focus on improvement function of liver(肝) and kidney(腎).Conclusion : We compared Korean and western medicine to understand melanin. We also interpreted the mechanism of melanin and pigmantary disorders in western medicine and considered the relationship with visceral manifestation theory(臟象論) in traditional Korean medicine. Further studies are needed to apply comprehension of melanin to clinical stage.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.2 no.2 s.3
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• pp.31-42
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• 2003

Prepaid plastic card issued by Korea Highway Company had a lot of problems in end-user usage and management. HipassPLUS Card, which is a smart card used for a prepaid electronic payment, overcomes the problems of Prepaid Plastic card. HipassPLUS Card is also designed be compatible to other cards such as public transportation card. Thus, for the safety of using the card in such environment, the functionality and the security of HipassPLUS card should be faultless. This paper developed a test module including the test method, the test checklist, and the test procedure to examine the functionality and security of the payment mechanism of HipassPLUS card. The test module contains the method and the procedure to test the standard items according to the test checklist of HipassPLUS card. The test items and the test checklist of HirassPLUS card was selected under the provision of the specification of Korea Highway Company and ISO standard. The results of evaluation on HipassPLUS card using the proposed test module indicates that 4he HipassPLUS card satisfied the criteria under the characteristics of the functionality, security, and compatibility.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.1
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• pp.37-56
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• 2004

As part of the ongoing global process of airlines forming strategic alliances, Korean Air has become a member of the SkyTeam Alliance, while Asiana has joined the Star Alliance. However, as something akin to the Anti-Trust Immunity(ATI) initiative has not been ratified domestically, these two airlines have seen their roles within these strategic alliances significantly reduced. In keeping with its domestic airline liberalization policy the U.S. government has instituted a mechanism through which foreign airlines that join such strategic alliances with their American counterparts can be exempt from the U.S. antimonopoly law. As a result, U.S. airlines have been able to forge wide ranging cooperative relations with foreign airlines, and thus increased their competitiveness within the air transport industry. This study analyzes the applicability of this Anti-Trust Immunity initiative to the domestic environment.

• KSBB Journal
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• v.24 no.3
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• pp.259-266
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• 2009

AfsR2 in Streptomyces lividans, a 63-amino acid protein with limited sequence homology to Streptomyces sigma factors, has been known for a global regulatory protein stimulating multiple antibiotic biosynthetic pathways. Although the detailed regulatory mechanism of AfsK-AfsR-AfsR2 system has been well characterized, very little information about the AfsR2-dependent down-stream regulatory genes were characterized. Recently, the null mutant of afsS in S. coelicolor (the identical ortholog of afsR2) has been characterized through DNA microarray system, revealing that afsS deletion regulated several genes involved in antibiotic biosynthesis as well as phosphate-starvation. Through comparative DNA microarray analysis of afsR2-overexpressed S. lividans, here we also identify several afsR2-dependent genes involved in phosphate starvation, morphological differentiation, and antibiotic regulation in S. lividans, confirming that the AfsR2 plays an important pleiotrophic regulatory role in Streptomyces species.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.179-204
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• 1998

The purpose of this research was to investigate the efficacy of Goiwhasan extract powder on the gastric injuries, antiulcer, gastrointestinal tract and blood hemostasis. Animals were used through this studies mice and rats. All animals were divided into 3 groups, contol group(no treatment), sample Ⅰ group(375mg/kg administration), sample Ⅱ group(750mg/kg administration). The gastric injuries and ulcer have been made by using pyloric ligation, indomethacin, HCI-ethanol, acetic acid and then The histological observation was followed. In the gastrointestinal tract, gastric juice secretion, gastric acidity, pepsin output, blood gastrin and secretin level, transport potentials in the small and large intestine were checked. And studies on blood hemostasis were performed on normal hemostatic activities and plasma prothrombin time, plasma recalcification time, plasma fibrinogen levels in the hypoprothrombinemic mice induced by warfarin. The results were as follows: 1. The antigastric ulcer effects on the pyloric ligation, indomethacin, HCl-ethanol, acetic acid induced gastric injuries were shown in Sample Ⅱ group(p<0.05). 2. Through the morphologic examination on the acetic acid induced ulcer, Sample Ⅰ group showed mild regeneration of epithelium and slight decrease of periulcer edema then that of Control group, while Sample Ⅱ group showed more retraction of round ulcer site, remarkable loss of swelling and edema then that of Control group, and revealing the regenerated epithelium in the surrounding ulcer site. Thus it was noted that both Sample groups have antigastriculcer effects on the experimentally induced gastric ulcer. 3. The inhibitory effects on gastric juice were noted in both Sample Ⅰ group(p<0.05) and Sample Ⅱ group(p<0.01). However, only Sample Ⅱ group showed the inhibitory effects on total acidity and pepsin output(p<0.05). 4. The significant inhibition of blood gastrin level showed at 30 min.(P<0.05) and 90 min.(P<0.05) after starting medication in only Sample Ⅱ group, but significance of blood secretin level in both groups was not recognized. 5. Any significant changes in barium sulfate transport in the small intestine of mice was not recognized in both groups, but the significantly inhibitory effect in large intestine was recognized in both Sample Ⅰ group(p<0.05) and Sample Ⅱ group(p<0.001). 6. In hemostatic effect on both normal mice and hypoprothrombinemic mice induced by warfarin, the significantly shortening effect on coagulation time was seen in only Sample Ⅱ group(p<0.01). 7. On plasma prothrombin time in hypoprothrombinemic rat induced by warfarin, Sample Ⅱ group have shortened the prothrombin time significantly(p<0.001). 8. On plasma reclcification time in hypoprothrombinemic rat induced by warfarin, the recalcification time have been shortened significantly in both Sample Ⅰ group(p<0.05) and Sample Ⅱ group(p<0.01). 9. On plasma fibrinogen levels in hypoprothrombinemic rat induced by warfarin, the fibrinogen contents in Sample Ⅱ have been decreased significantly(p<0.01). Overall the above results suggest that Goiwhasan has an therapeutic efficacy on antigastric ulcer and blood hemostasis. Further studies would be needed on the interaction of its herbal medicine and its mechanism in the future.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.849-859
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• 2018

Herpes simplex virus type 2 (HSV-2) infection has been a public health concern worldwide. It is the leading cause of genital herpes and a contributing factor to cervical cancer and human immunodeficiency virus (HIV) infection. No vaccine is available yet for the treatment of HSV-2 infection, and routinely used synthetic nucleoside analogs have led to the emergence of drug resistance. The small molecule $Retro-2^{cycl}$ has been reported to be active against several pathogens by acting on intracellular vesicle transport, which also participates in the HSV-2 lifecycle. Here, we showed that Retro-2.1, which is an optimized, more potent derivative of $Retro-2^{cycl}$, could inhibit HSV-2 infection, with 50% inhibitory concentrations of $5.58{\mu}M$ and $6.35{\mu}M$ in cytopathic effect inhibition and plaque reduction assays, respectively. The cytotoxicity of Retro-2.1 was relatively low, with a 50% cytotoxicity concentration of $116.5{\mu}M$. We also preliminarily identified that Retro-2.1 exerted the antiviral effect against HSV-2 by a dual mechanism of action on virus entry and late stages of infection. Therefore, our study for the first time demonstrated Retro-2.1 as an effective antiviral agent against HSV-2 in vitro with targets distinct from those of nucleoside analogs.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.37-49
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• 2015

In Space Syntax, the greater the degree of integration between separate links, the greater the links' accessibility from the target network. As such, planning pedestrian walks so that links with high degrees of integration are connected, or else inducing high integration value land use are both valid options. The travel distribution model reflects how walking demand, or more specifically, the pedestrian, partakes in route choosing behavior that minimizes select criteria, notably level of discomfort, as measured using travel distance and time. The model thus demonstrates travel patterns associated with demand pertaining to minimization of discomfort experienced by the pedestrian. This research introduces a method that integrates Space Syntax and the pedestrian travel distribution model. The integrated model will determine whether regions with high degrees of integration are actually being used as pivots for pedestrian demand movement, as well as to explain whether the degree of integration is sustained at an appropriate level while considering actual movement demand. As a means to develop the integrated model, a method that combines display of the visibility of the space syntax network and road-divided links is proposed. The pedestrian travel distribution model also includes an alternative path finding mechanism between origin and destination, which allows for uniform allocation of demand.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.344-351
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• 2002

Chemical speciation and transport of heavy metals in soil environment could be controlled by humic acid. In order to understand the mechanism on competitive adsorption of Cd and Cu on the surface of humic acid extracted from peat, the charge development of humic acid were investigate through a batch adsorption experiment with a series of different background electrolytes levels. The competitive adsorption of Cd and Cu to the humic acid were estimated according to the model using the proton binding constant obtained from the above batch test. The affinity of Cu to the carboxyl group on the humic acid was higher than that of Cd, but the affinity to the phenolic group was lower than to the carboxyl group. It seems that the amount of adsorbed Cd and Cu could be estimated using the proton binding constant obtained from a solution with single background ion. However, it is difficult to interpret the competitive adsorption of Cd and Cu with the constant for single background ion.