• Journal of the Korean earth science society
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• v.24 no.1
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• pp.46-60
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• 2003

In Namyang Bay of western Korea, macrotidal-flat deposits are divisible into three late Quaternary units: Unit M1 of upper marine mud, Unit T1 of middle siderite-bearing terrestrial clay, and Unit M2 of lower marine mud. Unit M1 represents typical Holocene intertidal mudflat deposits, showing a coarsening-upward textural trend. It probably resulted from the continual retrogradation of tidal flat during the mid-to-late Holocene sea-level rise. Reddish brown-color Unit T1 consists of homogeneous clay with abundant freshwater siderite grains and plant remains. Unit T1 is clearly separated from the overlying Unit M1 by a sharp lithologic boundary. Radiocarbon age, siderite grains and lithologic features indicate that Unit T1 is originated from freshwater bog or swamp deposition infilling the localized topographic lows during the early Holocene age. Overlain unconformably by early Holocene swamp clay, Unit M2 is orange to yellow in color and mottled, suggesting significant degree of weathering during the sea-level lowstand. Such subaerial oxidation is confirmed in the vertical profiles of geotechnical properties, clay mineral assemblages and magnetic susceptibility. Unit M2 appears to be correlated with the upper part of the late Pleistocene tidal deposits developed along the western Korean coast. The sedimentary succession of the Namyang-Bay tidal-flat deposit provides stratigraphic information for the Holocene-late Pleistocene unconformity and also permits an assessment of the preservation potential of the late Pleistocene marginal marine deposit along the western coast of Korea.

• BMB Reports
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• v.51 no.9
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• pp.462-467
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• 2018

A previous study of ours indicated that Drosophila flightless-1 controls lipid metabolism, and that there is an accumulation of triglycerides in flightless-1 (fliI)-mutant flies, where this mutation triggers metabolic stress and an obesity phenotype. Here, with the aim of characterizing the function of FliI in metabolism, we analyzed the levels of gene expression and metabolites in fliI-mutant flies. The levels of enzymes related to glycolysis, lipogenesis, and the pentose phosphate pathway increased in fliI mutants; this result is consistent with the levels of metabolites corresponding to a metabolic pathway. Moreover, high-throughput RNA sequencing revealed that Drosophila FliI regulates the expression of genes related to biological processes such as chromosome organization, carbohydrate metabolism, and immune reactions. These results showed that Drosophila FliI regulates the expression of metabolic genes, and that dysregulation of the transcription controlled by FliI gives rise to metabolic stress and problems in the development and physiology of Drosophila.

• Toxicological Research
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• v.32 no.2
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• pp.133-140
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• 2016

Sulfasalzine is a widely administered drug against inflammatory-based disorders in human. However several cases of liver injury are associated with its administration. There is no stabilized safe protective agent against sulfasalazine-induced liver injury. Current investigation was designed to evaluate if N-acetylcysteine (NAC) and dithioteritol (DTT) as thiol reducing agents and/or vitamins C and E as antioxidants have any protective effects against sulfasalazine-induced hepatic injury in an ex vivo model of isolated rat liver. Rat liver was canulated and perfused via portal vein in a closed recirculating system. Different concentrations of sulfasalazine and/or thiol reductants and antioxidants were administered and markers of organ injury were monitored at different time intervals. It was found that 5 mM of sulfasalazine caused marked liver injury as judged by rise in liver perfusate level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) (p < 0.05). A significant amount of lipid peroxidation and hepatic glutathione depletion were detected in drug-treated livers, accompanied with significant histopathological changes of the organ. Administration of NAC ($500{\mu}M$), DTT (${400\mu}M$), Vitamin C ($200{\mu}M$), or vitamin E ($200{\mu}M$) significantly alleviated sulfasalazine-induced hepatic injury in isolated perfused rat liver. The data obtained from current investigation indicate potential therapeutic properties of thiol reductants and antioxidants against sulfasalazine-induced liver injury.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.3
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• pp.213-224
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• 2010

An optically controlled silicon MESFET (OPFET) was fabricated by diffusion process to enhance the quantum efficiency, which is the most important optoelectronic device performance usually affected by ion implantation process due to large number of process induced defects. The desired impurity distribution profile and the junction depth were obtained solely with diffusion, and etching processes monitored by atomic force microscope, spreading resistance profiling and C-V measurements. With this approach fabrication induced defects are reduced, leading to significantly improved performance. The fabricated OPFET devices showed proper I-V characteristics with desired pinch-off voltage and threshold voltage for normally-on devices. The peak photoresponsivity was obtained at 620 nm wavelength and the extracted external quantum efficiency from the photoresponse plot was found to be approximately 87.9%. This result is evidence of enhancement of device quantum efficiency fabricated by the diffusion process. It also supports the fact that the diffusion process is an extremely suitable process for fabrication of high performance optoelectronic devices. The maximum gain of OPFET at optical modulated signal was obtained at the frequency of 1 MHz with rise time and fall time approximately of 480 nS. The extracted transconductance shows the possible potential of device speed performance improvements for shorter gate length. The results support the use of a diffusion process for fabrication of high performance optoelectronic devices.

• Journal of Environmental Policy
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• v.2 no.2
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• pp.41-63
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• 2003

CDM(Clean Development Mechanism) project is said to be a mechanism, which profits both the investing country and the host country, while additionally contributing to the reduction of greenhouse gases of the earth as a whole. However in reality, most of the proposed projects do not end up in agreement because of the problems related to differences in recognition between the investing country and the host country of the CDM project. This outlines the background for this research which proposes a new design of institutional arrangements of CDM projects in the Northeast Asian region, mainly Japan, China and Korea. In addition, we investigate the feasibility of the proposed design. The research firstly focuses on the reduction in transaction costs that the participation of Korea will have on a Japan-China CDM project. This paper further emphasizes the potential gains that would materialize if a CDM project involved the whole Northeast Asian region, and not only one country. Our research suggests that an approximate reduction of 23% in transaction costs, and about 4% reduction in the total costs of a CDM project can be expected to follow the Korean participation. In addition to decreasing costs we find that a Korean involvement in a CDM project with Japan will lead to efficiency gains illustrated by a higher increase in the IRR(Internal rate of return) in a Japan-Korea project(11.45% to 12.21%) compared to an IRR incresement of 10.57% to 11.27% for a pure Japanese CDM project. Similar results of a rise in the IRR is found for the whole investment period of 20 years. We can hence conclude that Korean participation in a Japan-China CDM project would improve the implementation possibilities of CDM project in the Northeast Asia region.

• Journal of Korean Neurosurgical Society
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• v.30 no.8
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• pp.963-969
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• 2001

Objectives : Cord blood stem cells have been widely used as donor cells for bone marrow transplantation recently. These cells can give rise to a variety of hematopoietic lineages to repopulate the blood. Recent observations reveal that some bone marrow cells and bone marrow stromal cells(MSCs) can grow to become either neurons or glial cells. It is, however, unclear whether or not there exists stems cells which can differentiate into neurons in the blood during the early stages of postnatal life. Methods : Human cord blood stem cells were prepared from human placenta after full term delivery. To induce neuronal differentiation of stem cells, ${\beta}$-mercaptoethanol was treated. To confirm the neuro-glial characteristics of differentiated stem cells, immunocytochemical stain for NeuN, neurofilament, glial fibrillary acidic protein(GFAP), microtubule associated protein2(MAP2) was performed. RT-PCR was performed for detecting nestin mRNA and MAP2 mRNA. Results : We showed in this experiment that neuro-glial markers(NeuN, neurofilament, MAP2, GFAP) were expressed and axon-like cytoplasmic processes are elaborated in the cultured human cord blood stem cells prepared from new born placenta after full term delivery. Nestin mRNA was also detected in fresh cord blood monocytes. Conclusions : These results suggest that human cord blood derived stem cells may be potential sources of neurons in early postnatal life.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.2
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• pp.44-50
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• 2010

Recently, the crude oil price per one barrel in 2005 cost 49.4 dollars. But the value of crude oil in 2007 had ascended 68.4 dollars which was skyrocketed 38.5[%] owing to the sudden rise of energy price. As it has been growing the necessity of energy efficiency, energy intentive companies actively try to implement energy management system It has been studied to improve the energy saving for household sector using the smart metering system which can give the information of energy prices, pattern on real time to energy consumers and voluntarily lead the activities of energy saving. In this paper, we estimated potential benefits and value of smart metering system through california test.

• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.77-82
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• 2017

Thus, chemicals are managed under 9 related central government department and 16 relevant laws with program such as Process Safety Management and Offsite Consequence Analysis in korea. Guidelines for set the endpoint concentration for chemcals based on the ERPG-2 (Emergency Response Planning Guidelines-2) and AEGL-2 (Acute Exposure Guidelines Level-2). but ERPG and AEGL do not describe exposure for less than 10 minutes. because of this, each guidelines define criteria differently for short time less than 10 minutes exposure. This indefinite exposure criteria would give rise to a confusion in the chemical plants, and potentially lead to a critical decision making error when accidents happen. In an effort to apply guidelines with evenly-distributed initial time frame, AEGL concentrations within 10 minute exposure time were evaluated by examining statistical regression curves. The results were in good agreement with those from the Probit Function based on each AEGL grade to explain 3 different threshold levels of exposure effects. Resultant re-enforced guidelines for endpoint chemical concentrations are, therefore, to provide powerful tool to assess and manage the risk associated with any potential chemical accidents at an early stage.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.112-119
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• 2005

This study attempts to suggest new directions of urban multi-family housing design in the recent era of information, in which the representation of publicity and privacy of the housing reflects new meanings and relationships of the current digital society. The study examines cases of Dutch multi-family housing and investigates the meanings and relationships of publicity and privacy in the building as well as unit design of the housings. Borneo-Sporenburg housing development is a good example that suggests new interpretation and design solution for low-rise, high-density multi-family housing. Thus, this study analyzes street patterns, facade design, and ways of housing unit combination in Borneo-Sporenburg housing and concludes as follows. First, public space in Borneo-Sporenburg housing, which was designed differently from hierarchical and centripetal organization of modern architecture, is divided into small units and spread into the inside, which provides high potential for personal control of space and personal programming of space by space choices. Second, street pattern and facade design of Borneo-Sporenburg housing provide visual publicity and privacy simultaneously as they maintain unity as a whole as well as articulate individual unit in many different ways and provide clues to neighboring. Streets as a public domain have self-controlled boundaries for residents and introduce voluntary use-programs for residents. Third, facades of the housing have no inter-mediate space or common space, and confront streets directly. Space in-between is composed inside the facade and extends into the streets by residents' own choices. Fourth, privacy and individuality of the housing is strengthened. Units of the housing have individual entrances, unique plan type and complicated combination of space that all together emphasize individuality of units, however they are not often notified from the outside.

• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.891-899
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• 2016

The recently isolated aniline-degrading bacterium Pseudomonas migulae AN-1 was tagged with green fluorescent protein (GFP) to investigate its bioaugmentation potential against aniline-contaminated groundwater through microcosm experiments. The survival and cellular response of GFP-tagged AN-1 introduced in a lab-scale aquifer corresponded directly with aniline consumption. During the process, the GFP-tagged AN-1 biomass increased from 7.52 × 10⁵ cells/ml to 128 × 10⁵ cells/ml and the degradation rate of aniline was 6.04 mg/l/h. GFP-tagged AN-1 was moderately hydrophobic (41.74%-47.69%) when treated with 20-100 mg/l aniline and exhibited relatively strong hydrophobicity (55.25%-65.78%) when the concentration of aniline was ≥100 mg/l. The membrane permeability of AN-1 increased followed by a rise in aniline below 100 mg/l and was invariable with aniline above 100 mg/l. Pyrosequencing analysis showed that the relative abundance of Proteobacteria (accounted for 99.22% in the non-bioaugmentation samples) changed to 89.23% after bioaugmentation with GFP-tagged AN-1. Actinobacteria increased from 0.29% to 2.01%, whereas the abundance of Firmicutes barely changed. These combined findings demonstrate the feasibility of removing aniline in aquifers by introducing the strain AN-1 and provide valuable information on the changes in the diversity of dominant populations during bioaugmentation.