• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.117-131
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• 2013

2010 eruption of Eyjafjallajokull volcano in Iceland and 2011 Shinmoedake's eruption in Japan evoked concerns from researchers for the possibility of explosion of Baekdusan volcano after long dormancy (repose period). National Emergency Management Administration has tried to evaluate the vulnerability of volcanic disaster and to prepare response to the potential risk and to mitigate the damages from the volcanic eruption, but a few studies have focused on the activities of Baekdusan. This study aims to clarify what the criteria between dormant volcano and active volcano based on geomorphologists' and geologists' researches. Volcanic experts have made a criterion of activeness such as the evidence of volcanic eruption within 10,000 year before present. More rigorous criterion which was made in 1991 by Japanese Meteorological Administration was 2000 years B.P. Both Baekdusan and Hallasan satisfy two criteria, so it is necessary for us to monitor the activity of both volcanoes and to reflect the facts into the curriculum.

• Journal of Pharmaceutical Investigation
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• v.33 no.2
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• pp.91-97
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• 2003

During the preparation of decoction from the mixture of Coptidis Rhizoma and Scutellariae Radix, insoluble copreciptate was formed. The coprecipitated product (COP) was composed of berberine and baicalin which was the active ingredient of Coptidis Rhizoma and Scutellariae Radix, respectively. COP was slightly soluble in water and could not be well absorbed after oral administration. This poor bioavailibility might be associated with its poor aqueous solubility. With the purpose of increasing the solubility and bioavailibility of COP, hydrolysis of COP by ${\beta}-glucuronidase$ was carried out. Hydrolyzed products (HOP) of COP were identified and assayed for active ingredients. The partition coefficient study, in situ absorption test, and pharmacokinetic study after oral administration were also performed. COP was found to be consisted of berberine and baicalin with molecular ratio of 1 to 1. This compound was hydrolyzed to berberine and baicalin by ${\beta}-glucuronidase$. The rate of hydrolysis was higher at higher temperature up to $50^{\circ}C$ and higher concentration of ${\beta}-glucuronidase$ up to 2500 unit under our experimental conditions. Baicalein, which is more liphophilic than baicalin, showed greater absorption in small intestine than baicalin did. The plasma concentrations of berberine and baicalein after oral administration of HOP were significantly higer than those of COP. The possible mechanism of increased bioavailibility of berberine and baicalein could be the hydrolysis of COP by ${\beta}-glucuronidase$. On the basis of the above results, it might be said that HOP should be a suitable preparation for increasing the bioavailibility of Coptidis Rhizoma and Scutellariae Radix.

• Korean Journal of Medicinal Crop Science
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• v.15 no.1
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• pp.6-11
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• 2007

This study was conducted to identify physiologically active substances from leaves and stems of peony plant. MeOH extracts and column chromatography were employed to isolate active compounds and chemical structure were identified by IR, UV, Mass and NMR. The results obtained can be summerized as followings : Chemical structure of compound 1 was identified as oleanolic acid (white color form) of triterpenoid group, which is firstly identified from the above part of peony. Compound 2 was identified as kaempferol (yellow needle form) of flavonoid group, which was firstly identified from the root, leaf and stem of peony. Compound 3 was identified as methyl gallate (white power form) of phenol group, which was firstly identified from the above part of peony. Compound 4 was identified as astragalin (bright yellow needle form) of flavonoid group, that was firstly identified from the leaf and stem of peony. Compound 5 was identified as paeoniflorin (white color form) of monoterpene group, that was firstly identified from the above part of peony.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.4
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• pp.273-285
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• 2022

Using data from a departmental profit and loss management questionnaire survey conducted for a group of hospitals consisting of various establishment entities, this study evaluates the effectiveness of departmental profit and loss management practices, such as break-even analysis, based on objective performance data. The study also examines whether the implementation of departmental profit and loss accounting is still effective in improving profitability in the financial year 2021 and whether the effectiveness of the implementation of departmental profit and loss accounting is robust. This study reconfirmed that the implementation of departmental profit-and-loss accounting has a positive effect on objective financial performance in hospitals and that the effect of improving profitability can be enhanced by implementing it monthly with high frequency and regularity and by using the accounting results more actively. It was also found that the department's implementation of break-even analysis had a positive impact on financial performance, which was enhanced by more active use of the data. Given the current economic climate, a hospital organization's active participation in income statement management, not only for the hospital as a whole but also for each department, would be an effective management activity.

• Journal of Ginseng Research
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• v.48 no.1
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• pp.59-67
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• 2024

Background: Alzheimer's disease (AD) has memory impairment associated with aggregation of amyloid plaques and neurofibrillary tangles in the brain. Although anti-amyloid β (Aβ) protein antibody and chemical drugs can be prescribed in the clinic, they show adverse effects or low effectiveness. Therefore, the development of a new drug is necessarily needed. We focused on the cognitive function of Panax ginseng and tried to find active ingredient(s). We isolated panaxcerol D, a kind of glycosyl glyceride, from the non-saponin fraction of P. ginseng extract. Methods: We explored effects of acute or sub-chronic administration of panaxcerol D on cognitive function in scopolamine- or Aβ_25-35 peptide-treated mice measured by several behavioral tests. After behavioral tests, we tried to unveil the underlying mechanism of panaxcerol D on its cognitive function by Western blotting. Results: We found that pananxcerol D reversed short-term, long-term and object recognition memory impairments. The decreased extracellular signal-regulated kinases (ERK) or Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) in scopolamine-treated mice was normalized by acute administration of panaxcerol D. Glial fibrillary acidic protein (GFAP), caspase 3, NF-kB p65, synaptophysin and brainderived neurotrophic factor (BDNF) expression levels in Aβ_25-35 peptide-treated mice were modulated by sub-chronic administration of panaxcerol D. Conclusion: Pananxcerol D could improve memory impairments caused by cholinergic blockade or Aβ accumulation through increased phosphorylation level of ERK or its anti-inflammatory effect. Thus, panaxcerol D as one of non-saponin compounds could be used as an active ingredient of P. ginseng for improving cognitive function.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.95-101
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• 2008

The gene encoding a putative esterase of Xanthomonas oryzae pv. oryzae was cloned using PCR technique. The gene was expressed with His6 tag in E. coli. One-step purification of the recombinant esterase with Ni-NTA resin resulted in one band by SDS-PAGE analysis. The purified enzyme showed a molecular weight of 30 kDa, as expected, therefore the enzyme was a mononer. The enzyme was the most active toward p-nitrophenyl (p-NP) acetate and p-NP-butyrate to a lesser extent. However, the enzyme could not hydrolyze p-NP-myristate, palmitate, and stearate. Therefore, the enzyme is considered as an esterase, very different from lipase. The purified esterase had optimal pH at around 8.0 and was stable in a broad range of pH values. The optimal temperature ranged from 30 to $40^{\circ}C$, and the residual activity observed after heat treatment at $55^{\circ}C$ for 20 min was 72 % of the initial activity. The activity was inhibited by the presence of copper and cobalt ions.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.63-68
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• 2003

We investigated the sequence divergence of the geographic samples of the queen bumble bee (Bombus ardens) in Korea. A portion of mitochondrial COI gene sequences (423 bp) was analyzed for 44 individuals collected from seven localities. Sequence analysis resulted in four COI haplotypes with the maximum nucleotide divergence of only 0.5% (two bp). One haplotype (BA1) was dominant in all localities surveyed (86.4%). The finding of low sequence divergence and dominance of one haplotype appear to reflect, although limited, the life history of the B. ardens queens subjected to active dispersal and seasonal fluctuation in queen number.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.519-526
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• 2020

Methamphetamine (MA) is one of the most commonly abused drugs in the world by illegal drug users. Addiction to MA is a serious public health problem and effective therapies do not exist to date. It has also been reported that behavior induced by psychostimulants such as MA is related to histone deacetylase (HDAC). MeBib is an HDAC6 inhibitor derived from a benzimidazole scaffold. Many benzimidazole-containing compounds exhibit a wide range of pharmacological activity. In this study, we investigated whether HDAC6 inhibitor MeBib modulates the behavioral response in MA self-administered rats. Our results demonstrated that the number of active lever presses in MA self-administered rats was reduced by pretreatment with MeBib. In the hippocampus of rats, we also found MA administration promotes GluN2B, an NMDA receptor subunit, expression, which results in sequential activation of ERK/CREB/BDNF pathway, however, MeBib abrogated it. Collectively, we suggest that MeBib prevents the MA seeking response induced by MA administration and therefore, represents a potent candidate as an MA addiction inhibitor.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.1
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• pp.301-311
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• 2020

With the recent global urban issues such as climate change, urbanization, and energy problems, the smart city was proposed as one of the solutions in urban planning. This study introduces the smart city initiatives of South Korea by examining the recent history of smart city policies and their limitations. This case study reflects the experience of one of the countries which thrived to building smart cities as their national key industries to drive economic growth. It also analyzes the trends of the smart city using big data analysis techniques. Although there are obstacles such as economic recession, failing to differentiate from the U-city, low service level than expected smart functionality, We could recognize the current status of the smart city policies in South Korea such as 1) Korean smart city development projects are actively implemented, 2) public consensus suggests that applying advanced technology and the active role of government need, 3) a comprehensive and strategic approach with the integration and application of advanced technologies is required as well, 4) investment by both private and public sectors need to deliver social improvements. This study suggests future direction of smart city polity in South Korea in the conclusion.

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1475-1484
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• 2016

To analyze the cooling effect of urban green areas, we conducted micrometeorological measurements in these areas and their surroundings in Seoul, Korea. From the average hourly temperature measurements through each month for the last two years (March 2013 to February 2015), we found that the maximum temperature difference between urban and green areas was about $2.9^{\circ}C$ at 16:00 LST in summer, and the minimum was about $1.7^{\circ}C$ at 22:00 LST in winter. In summer, the temperature difference was the largest during the day, rather than at night, due mainly to shading by the tree canopy. The specific humidity difference between the two areas was about $1.5g\;kg^{-1}$ in summer, and this decreased in the winter. The specific humidity difference between urban and green areas in summer is relatively large during the day, due to the higher evapotranspiration level of biologically active plants.