• Applied Biological Chemistry
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• v.42 no.2
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• pp.99-104
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• 1999

Soil actinomycetes of 703 strains were isolated from 25 sampling points in Cheju Island using 4 different media. Arginine glycerol salts agar containing soil extract was found to be the best medium for the isolation of soil actinomycetes. Soil samples from pasture land showed higher population and diversity of the actinomycetes than those from citrus field, forest, island, hill or valley. When the antibacterial activity of the 526 isolates was tested against three bacterial strains, Escherichia coli, Staphylococcus aureus and Pseudomonas solanacearum the frequency of the isolates with antibacterial activity varied much depending upon the media used for isolation and cultivation. BL106Ba, one of the 10 isolates that showed antibacterial activity against all the above 3 test strains, was chosen based upon the pH and heat stability of its antibacterial metabolites, and was identified as Streptomyces sp. based upon its cultural, morphological and physiological characteristics. The partially purified white crystalline substance obtained from the culture supematant of BL1063a through cation exchange chromatography(AG MP-50) and three times consecutive gel filtration(Sephadex G-10) showed high antimicrobial activity against gram positive and negative bacteria, but low activity against yeasts. The partially purified substance was found to contain at least four different compounds with antibacterial activity by both thin layer chromatography and high performance liquid chromatography.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.3
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• pp.206-213
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• 2008

We observed the physical and chemical properties of a soil on pine mushroom picking areas where were located in the most upper and lower parts showing a comparative climatic characteristics in Korea. The slope gradients within the investigation areas which were divided into 100 quadrates of $1m^2$ ranged from $5.7{\sim}8.6{\beta}$ to $24{\sim}22.7{\beta}$ (left to right) and $4.5{\sim}6.8{\beta}$ to $13.5{\sim}17.8{\beta}$ (top to bottom) for Ponghwa and Gansung, respectively. The amount of clay and thickness of organic matter were significantly decreased with increasing slope gradient, resulting in decrease of the soil moisture content around a fairly ring-colony of Tricholoma matsutake which was observed under the relatively thicker organic matter layer beyond 3 cm depth. Soil pHswere weak acid and average EC was $0.44dS\;m^{-1}$ in both areas. The cations were in the order of Fe K > Na > Mg > Ca and Fe > K > Na > Ca > Mg for the upper(Gansung) and the lower (Ponghwa) part. And the amount of Fe was approximately $80dS\;m^{-1}$ or greater in the pine mushroom picking soil. From this, we could assume that the growth of the pine mushroom was closely related not only with iron but also soil moisture content.

• Korean Journal of Veterinary Research
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• v.33 no.2
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• pp.295-300
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• 1993

Central nervous system of two dogs with natural canine distemper was investigated histopathologically and immunocytochemically with antisera to MBP, MAG and GFAP. Histopathologically, there were neuronal degeneration and diffuse gliosis in the cerebrum, vacuolar degeneration, hypertrophy of astrocytes and demyelination in cerebellar white matter adjacent to the 4th ventricle and optic tracts showing non-inflammatory demyelinating encephalomyelitis (Summers and Appel, 1987). Immunohistochemically, there was a concurrent disappearance of MBP and MAG in the well developed demyelinating lesion in the cerebellar white matter. At the margin of demyelination, Loss of both MBP and MAG varied on the stage of demyelinating process. GFAP-positive astrocytes were hypertrophied and contained canine distemper virus intranuclear inclusions. GFAP-positive fibers were increased at the early stage of demyelination, and then were not immunoreaeted at the well developed demyelination. Hypertrophic astrocytes with intranuclear inclusions were commonly identified in the interfascular layer without myelin vacuolation and demyelination. This is the first study of primary demyelination and astroglial reactions in natural CDE investigated using immunocytochemistry of two myelin proteins and GFAP. Concurrent loss of MBP and MAG suggest that the myelin sheath is the target in the demyelinating process in CDE.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.1
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• pp.35-43
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• 2003

Recent geomorphological changes and late Quaternary depositional sequences of Gwangyang Bay are studied based on bathymetric maps, surface sediments, and seismic profiles. As a result of the reclamation of coastal area for an industrial complex construction, the coastline of Gwangyang Bay has rapidly been changed and the area of it has now been reduced by about 25 ％ in the last 30 years. In addition, the bottom topography is actively modified by dredging for navigation channels. In surfical sediment distribution, the western part of Gwangyang Bay is dominated by mud facies, whereas the eastern part of the Bay is dominated by sand-mud mixing facies. Depositional sequences above the basement are divided into two units: Unit I in upper layer and Unit II in lower one. These depositional units are unconformably bounded by middle reflector-M. Unit II, mostly occupying the channel areas, is interpreted as fluvial-origin deposits during sea-level lowstand. Unit I typically shows a progradational pattern from the Seomjin River mouth to the Yeosu Strait, which is interpreted as deltaic deposits supplied from the Seomjin River during the Holocene sea-level highstand. The shallow gas within the sediments Is widely distributed in most area, and locally exposed onto the sea-bed due to dredging.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.1
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• pp.8-13
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• 1997

The Holocene mud deposits in the southeastern innershelf of the Korean Peninsula were studied using the shallow seismic reflection profiles coupled with sediment sampling. The Holocene mud deposits are developed as a belt in the innershelf area from the mouth of the Nakdong River to off Pohang along the coastline. The surficial sediments in the study area gradually become finer and well sorted from south to north. The seismic facies in the Holocene sequence change northward from parallel reflectors in the mouth of the Nakdong River and northeastward prograding reflectors in the southern part off Ulsan to transparent layer in the nearshore off Ulsan to Pohang. The regional difference of seismic facies indicates that the Holocene sediment characters are varied with localities. By combining the surficial sediments properties with seismic facies patterns, the suspended sediments mostly supplied from the Nakdong River may be transported northward along the shore by the north-flowing Tsushima warm current. The Holocene mud sequence overlying the ravinement surface which is produced by erosion of underlying sediments during a rapid transgression can be interpreted as the highstand system tracts probably formed during the highstand of sea level similar to the present-day sea level.

• World Technopolis Review
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• v.8 no.2
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• pp.74-81
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• 2019

Cities will soon host two third of the population worldwide, and already today 80% of the world energy is used in the 20 largest cities. Urban areas create 80% of the greenhouse gas emission, so we should take care that urban areas are smart and sustainable as implementations have especially here the greatest impact. Smart Cities (SC) or Smart Sustainable Cities (SSC) are the actual concepts that describe methodologies how cities can handle the high density of citizens, efficiency of energy use, better quality of life indicators, high attractiveness for foreign investments, high attractiveness for people from abroad and many other critical improvements in a shifting environment. But if we talk about Entrepreneurship Ecosystem and Innovation, we do not see a lot of literature covering this topic within those SC/SSC concepts. It seems that 'Smart' implies that all is embedded, or isn't it properly covered as brick stone of SC/SSC concepts, as they are handled in another 'responsibility silo', meaning that the policy implementation of a Science and Technology Park (STP) is handled in another governing body than SC/SSC developments. If this is true, we will obviously miss a lot of synergy effects and economies of scale effects. Effects that we could have in case we stop the siloed approaches of STPs by following a more holistic concept of a Smart Sustainable City, covering also a continuous flow of innovation into the city, without necessarily always depend on large corporate SSC solutions. We try to argue that every SSC should integrate SP/STP concepts or better their features and services into their methodology. The very limited interconnectivity between these concepts within the governance models limits opportunities and performance in both systems. Redesigning the architecture of the governance models and accepting that we have to design a system-of-systems would support the possible technology flow for smart city technologies, it could support testbed functionalities and the public-private partnership approach with embedded business models. The challenge is of course in complex governance and integration, as we often face siloed approaches. But real SSC are smart as they are connecting all those unconnected siloes of stakeholders and technologies that are not yet interoperable. We should not necessarily follow anymore old greenfield approaches neither in SSCs nor in SP and STP concepts from the '80s that don't fit anymore, being replaced by holistic sustainability concepts that we have to implement in any new or revised SSC concepts. There are new demands for each SP/STP being in or close to an SC/SCC as they have a continuous demand for feeding the technology base and the application layer and should also act as testbeds. In our understanding, a big part of STP inputs and outputs are still needed, but in a revised and extended format. We know that most of the SC/STP studies claim the impact is still far from understood and often debated, therefore we must transform the concepts where SC/STPs are not own 'cities', but where they act as technology source and testbed for industry and new SSC business models, being part of the SC/STP concept and governance from the beginning.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.27-27
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• 2011

For the design of real applicable molecular devices, current-voltage properties through molecular nanostructures such as metal-molecule-metal junctions (molecular junctions) have been studied extensively. In thiolate monolayers on the gold electrode, the chemical bonding of sulfur to gold and the van der Waals interactions between the alkyl chains of neighboring molecules are important factors in the formation of well-defined monolayers and in the control of the electron transport rate. Charge transport through the molecular junctions depends significantly on the energy levels of molecules relative to the Fermi levels of the contacts and the electronic structure of the molecule. It is important to understand the interfacial electron transport in accordance with the increased film thickness of alkyl chains that are known as an insulating layer, but are required for molecular device fabrication. Thiol-tethered RuII terpyridine complexes were synthesized for a voltage-driven molecular switch and used to understand the switch-on mechanism of the molecular switches of single metal complexes in the solid-state molecular junction in a vacuum. Electrochemical voltammetry and current-voltage (I-V) characteristics are measured to elucidate electron transport processes in the bistable conducting states of single molecular junctions of a molecular switch, Ru(II) terpyridine complexes. (1) On the basis of the Ru-centered electrochemical reaction data, the electron transport rate increases in the mixed self-assembled monolayer (SAM) of Ru(II) terpyridine complexes, indicating strong electronic coupling between the redox center and the substrate, along the molecules. (2) In a low-conducting state before switch-on, I-V characteristics are fitted to a direct tunneling model, and the estimated tunneling decay constant across the Ru(II) terpyridine complex is found to be smaller than that of alkanethiol. (3) The threshold voltages for the switch-on from low- to high-conducting states are identical, corresponding to the electron affinity of the molecules. (4) A high-conducting state after switch-on remains in the reverse voltage sweep, and a linear relationship of the current to the voltage is obtained. These results reveal electron transport paths via the redox centers of the Ru(II) terpyridine complexes, a molecular switch.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.127-134
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• 2005

Although the bulk composition of materials is one of the major considerations in extractive metallurgy and environmental science, surface composition and topography control surface reactivity, and consequently play a major role in determining metallurgical phenomena and pollution by heavy metals and organics. An understanding of interaction mechanisms of different chemical species at the mineral surface in an aqueous media is very important in natural environment and metallurgical processing. X-ray photoelectron spectroscopy (XPS) has been used as an ex-situ analytical technique, but the material to be analyzed can be any size from $100\;{\mu}m$ up to about 1 cm. It can also measure mixed solids powders, but it is impossible to ascertain the original source of resulting x-ray signals where they were emitted from, since it radiates and scans the macro sample surface area. The study demonstrated the ability of TOF-SIMS to detect individual organic species on the surfaces of mineral particles from plant samples and showed that the TOF-SIMS techniques provides an excellent tool for establishing the surface compositions of mineral grains and relative concentrations of chemicals on mineral species.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.215-220
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• 2007

This study was conducted to examine the establishment of bovine ES-like cells having pluripotency. The hatched blastocysts derived from culture of in vitro fertilized embryos for 10 to 12 days dissociated mechanically into ICM-and trophectoderm-rich clumps using needle, and cultured onto mitotically-inactivated MEF feeder layer. The primary colonies originated from ICM cells were detached mechanically 7 days after seeding and subsequent subculture was conducted at intervals of every 5 to 7 days. Two ES -like cell lines were established and maintained over 40 passages. Self-renewal of the established lines was confirmed by examining the alkaline phosphatase activity, stem cell-specific marker profiles including SSEA isotopes, Oct-4 and STAT3. Moreover, the established cell lines could produce anchorage-independent embryoid bodies (EBs) with gradual decrease of Oct-4 transcript level in time-dependent manner.

• Analytical Science and Technology
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• v.15 no.3
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• pp.236-242
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• 2002

A method was investigated to determine the thickness of coating on steel sheet using rf glow discharge atomic emission spectrometer. The RF gas-jet boosted glow discharge has such salient feature as good pleasure stability and high sputtering efficiency that it was possible to determine the thickness of silicon resin film on zinc electroplated steel. The erosion speed variation is dependent on discharge power, gas flow rate and discharge pressure. therefore determine discharge condition to measure the thickness of coating on steels. The fundamental studies have been carried out to investigate an optimum condition for in-depth analysis and composition of zinc coating on steel. In this study, the calibration curve for thickness determination of silicon resin film was found to be linear in the range of $1000{\sim}3500mg/m^2$ film thickness. The developed rf gas-jet boosted glow discharge was applied to the analysis of zinc coating and silicon resin film on steel made by RIST.