• Journal of Wetlands Research
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• v.21 no.1
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• pp.84-94
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• 2019

The Seocheon and Yubu Island mudflats in Geum Estuary are important stopover sites for migratory birds as energy supplementation area in the East Asia-Australasian Flyway. Benthic invertebrates in the tidal flats are important food resources for the migratory birds. In other words, benthic invertebrates in the tidal flats play an important ecological role in energy flow. This study was conducted to investigate the relationship between benthic invertebrate assemblages and environmental factors in Seocheon and Yubudo tidal flats in the Geum Estuary. As a result of the benthic invertebrate assemblage during the fall migration season, the total species number was 147, density and biomass were $1,772{\pm}1,342individuals/m^2$ and $445.1{\pm}807.6g/m^2$, respectively. Based on the appearance species and the density data, the result of analysis of mutual similarity among sampling sites was divided into two groups. Group A was the Macrophthalmus-Heteromastus community and Group B was the Spio-Urothoe-Mandibulophoxus community. Group B showed higher mean species number, density and biomass than Group A. The BIO-ENV analysis showed that the benthic invertebrate assemblages were most affected by the combination of sand content % and sediment sorting (${\rho}=0.500$). The variables of significant relationship with species number and biomass were sediment sorting (p=0.015) and the pore water DO(Dissolved Oxygen, p=0.003) in sediment, respectively.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.195-199
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• 2013

A bacterial strain MPL-01 was isolated from the large intestine of a wild boar. The strain was shown to have morphological, physiological and biochemical characteristics, fatty acids composition typical of Bacillus. The 16S rRNA gene sequence showed that the isolate formed distinct phyletic line that was most closely related to this of Bacillus atrophaeus (99.99%). It was proposed that the strain is classified as B. atrophaeus MPL-01. The strain MPL-01 exhibited the strongest antifungal activity against Colletotrichum acutatum, the pathogen of anthracnose of chili peppers. The ethyl acetate extract of culture filtrate possessed not only the antifungal activity but also the bio-surfactant activity. Therefore, the strain MPL-01 could be a useful bacterium in the development of bio-control process against the pathogenic fungi.

• BMB Reports
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• v.29 no.2
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• pp.156-162
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• 1996

Transcription of hepatitis B viral pregenomic promoter is known to be regulated mainly by the combined interaction of enhancers I, II and the intervening regulatory sequences between the two enhancers. A positive regulatory element was identified by serial deletion and measuring the linked chloramphenicol acetyltransferase (CAT) activities, which overlapped with the 5' region of the X open reading frame. When the positive regulatory element was inserted upstream of the SV40 early promoter, it elevated SV40 promoter activity in HepG2 cells. Two cellular proteins of 110 (p110) and 33 (p33) kDa interacted with the positive element and both of them were present in the nucleus, but p110 also existed in the cytoplasm in phosphorylated form. Dephosphorylation of p110 by acid phosphatase enhanced the DNA-binding activity of p110. The p33 could bind to single-strand DNA specifically as well as to double-strand DNA.

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1297-1304
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• 2009

A novel series of imidazo[1,2-$\alpha$]pyridines was designed, synthesized, and tested for their ability to inhibit acyl- CoA:cholesterol acyltransferase. Preliminary lead optimization efforts resulted in the identification of ACAT inhibitors represented by analogues 5b, 5c, 6a, 6c, 7b, and 7c. The ACAT inhibitory activity of these compounds was further established by potent inhibition of cholesteryl ester formation in HepG2 cells by a representative analogue 7b.

• The KIPS Transactions:PartB
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• v.11B no.5
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• pp.587-596
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• 2004

During recent years, a new framework, which aims to bring a unified and global approach in indexing, browsing and querying various digital multimedia data such as audio, video and image has been developed. This new system partitions each media stream into smaller units based on actual physical events. These physical events within oath media stream can then be effectively indexed for retrieval. In this paper, we present a new approach that exploits audio, image and video features to segment and analyze the audio-visual data. Integration of audio and visual analysis can overcome the weakness of previous approach that was based on the image or video analysis only. We Implement a web-based multi media data retrieval system called XCRAB and report on its experiment result.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1043-1049
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• 2014

Density functional theory (DFT) calculations at the B3LYP/6-31G(d,p) theoretical level were performed for two novel explosives (compounds B and C) based on the guanidine-fused bicyclic skeleton $C_4N_6H_8$ (A). The heats of formation (HOFs) were calculated via isodesmic reaction. The detonation properties were evaluated by using the Kamlet-Jacobs equations. The bond dissociation energies (BDEs) for the thermolysis initiation bond were also analyzed to investigate the thermal stability. The results show that the compounds have high positive HOF values (B, 1064.68 $kJ{\cdot}mol^{-1}$; C, 724.02 $kJ{\cdot}mol^{-1}$), high detonation properties (${\rho}$, D and P values of 2.04 $g{\cdot}cm^{-3}$ and 2.21 $g{\cdot}cm^{-3}$, 9.98 $km{\cdot}s^{-1}$ and 10.99 $km{\cdot}s^{-1}$, 46.44 GPa and 59.91 Gpa, respectively) and meet the basic stability requirement. Additionally, feasible synthetic routes of the these high energy density compounds (HEDCs) were also proposed via retrosynthetic analysis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.12
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• pp.1024-1032
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• 2007

The flow characteristics with the impinging angles of defrost nozzle jet inside a commercial vehicle passenger compartment were investigated experimentally by using the two-dimensional duct-nozzle model. The shape of the nozzle contraction was designed according to the curved line of cubic equation to the vertical plan of the flow direction. The impinging angles, defined as the angle between nozzle axis and a vertical line to the windshield, were varied from the $0^{\circ}\;to\;80^{\circ}$. The mean velocity distributions, the half-widths, and the momentum distributions with the cases of both the free jet and the impinging jet onto the dummy windshield were measured. The impinging jet flows similarly with wall jet from $X/b_o=20$, and the impinging angle has an effect on the half-width of the impinging jet. The momentum distributions onto the windshield increased with the increase of impinging angle, and then their inflection point was observed around the impinging angle of $60^{\circ}$.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.64-64
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• 1995

Cholesteryl Ester Transfer Protein (CETP) mediates the transfer of cholesterol ester and triglyceride between high-density lipoprotein (HDL) and other low-density lipoproteins, therefore, it might influence HDL levels. The levels of HDL is closely related to the atherogenic diseases in human and there were several reports that the trasgenic mice expressing CETP had much worse atherosclerosis than non-expressing control one. Therefore, selective inhibitors of CETP have the potential to be used as antiatherosclerotic agents. Continued screening for potent inhibitors of CETP led to the isolation of Suberitenone B from marine sponge. Suberitenone B, sesterterpenoids of a new skeletal class have been isolated from the sponge Suberites sp. collected from King George Island the Antartic. The structure of the metabolite has been determined by NMR experiments and chemical methods.

• Journal of the Korean Society for Heat Treatment
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• v.37 no.3
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• pp.128-137
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• 2024

In this study, the carburizing heat treatment process used in aircraft gear manufacturing was compared with the general carburizing heat treatment process using AISI 9310 steel. The process of carburizing followed by slow cooling, and then quenching after austenitizing(Process A) showed less compressive residual stress and less retained austenite in the surface layer compared to the process of quenching directly after carburizing(Process B). In prpcess B, there was a large amount of retained austenite when quenched immediately after carburization, and when treated with subzero, martensite rapidly increased and the compressive residual stress increased significantly, but at the same time, there is a risk of cracking due to severe expansion in volume. Therefore, in the case of aviation parts, it is believed that a step-by-step heat treatment cycle was adopted to ensure stability against heat treatment cracks. As a result of the final tempering after sub-zero treatment, the A process specimen showed a deeper effective case depth and HV700 depth and a higher hardness value above HV700 than the B process specimen.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.1
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• pp.28-35
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• 2008

Purpose: The nitric oxide (NO) release by inducible nitric oxide synthase (iNOS) is the key events in macrophage response to lipopolysaccharide (LPS) which is suggested to be a crucial mediator for inflammatory and innate immune responses. NO is an important mediator involved in many host defense action and may also lead to a harmful host response to bacterial infection. However, given the importance of iNOS in a variety of pathophysiological conditions, control of its expression and signaling events in response to LPS has been the subject of considerable investigation. Materials and Methods: The Raw264.7 macrophage cell line was used to observe LPS-stimulated iNOS expression. The expression of iNOS is observed by Western blot analysis and real-time RT-PCR. Protein kinase C $(PKC)-{\alpha}$ overexpressing Raw264.7 cells are established to determine the involvement of $PKC-{\alpha}$ in LPS-mediated iNOS expression. $NF-{\kappa}B$ activity is measured by $I{\kappa}B{\alpha}$ degradation and $NF-{\kappa}B$ luciferase activity assay. Results: We found that various PKC isozymes regulate LPS-induced iNOS expression at the transcriptional and translational levels. The involvement of $PKC-{\alpha}$ in LPS-mediated iNOS induction was further confirmed by increased iNOS expression in $PKC-{\alpha}$ overexpressing cells. $NF-{\kappa}B$ dependent transactivation by LPS was observed and $PKC-{\alpha}$ specific inhibitory peptide abolished this activation, indicating that $NF-{\kappa}B$ activation is dependent on $PKC-{\alpha}$. Conclusion: Our data suggests that $PKC-{\alpha}$ is involved in LPS-mediated iNOS expression and that its downstream target is $NF-{\kappa}B$. Although $PKC-{\alpha}$ is a crucial mediator in the iNOS regulation, other PKC isozymes may contribute LPS-stimulated iNOS expression. This finding is needed to be elucidated in further study.