• Journal of Environmental Science International
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• v.16 no.12
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• pp.1411-1424
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• 2007

Long-term trends and distribution patterns of water quality were investigated in the Asan coastal areas of Yellow Sea, Korea from 1975 to 2005. Water samples were collected at 3 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids(SS), chemical oxygen demand(COD), dissolved oxygen(DO) and nutrients. Spatial distribution patterns were not clear among stations but the seasonal variations were distinct except COD, SS and nitrate. The trend analysis by principal component analysis(PCA) during twenty years revealed the significant variations in water quality in the study area, Annual water qualities were clearly discriminated into 4 clusters by PCA; year cluster 1988-1991, 1994-1997, and 1992-1993/1998-2005. By this multi-variate analysis we can summarize the annual trends as the followings; salinity, suspended solids and dissolved oxygen tended to increase from late 1980's, increased pH and COD from 1992, and decreased salinity and increased nitrogen and COD from 1990 due to the runoff frow agricultural lands causing eutrophication.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.174-179
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• 2018

Clithon retropictus has been protected by the Ministry of Environment as an endangered species since 1998 and has been listed on the state red list of endangered species category II. It is viewed as a representative for all endangered species in the northeastern coastal waters of Korea. Most of the habitats of C. retropictus have been found to be in an unstable state because of development projects such as road construction, small stream development, irrigation for securing agricultural water, and flood prevention. These habitats are damaged by small stream maintenance projects and development, and the risk of damage is increasing and active efforts are needed in order to protect them. Although the Ministry of Environment is striving to preserve this endangered species, the habitat of C. retropictus is still facing external threats because it spreads to only a small area at high densities. Therefore, in order to protect the habitat of C. retropictus, a level II endangered species, it is urgent to make an effort to minimize habitat damage and to take measures for its protection.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.818-826
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• 2013

To reduce the production cost of Lactobacillus, discarded red ginseng starch was collected from a factory of red ginseng extract in order to develop the Lactobacillus culture medium. According to the analysis of the gensenoside composition of red ginseng starch, the total gensenoside content of starch was 2.73 mg/g, and the gensenoside $Rb_1$, $Rb_2$ and $Rg_3$ contents were 0.1, 0.29 and 0.52 mg/g, respectively. For the preparation of the liquid media, red ginseng starch was added at rates of 0, 5, 10 and 20%. Further, Lactobacillus plantarum 15357 and Leuconostoc mesenteroides sub sp. strains were then inoculated to these prepared broths. With the red ginseng starch medium, the growth rates ($1.42{\times}10^7$ and $2.96{\times}10^{10}$ CFU/mL) and the final cell concentrations were higher than the MM medium ($1.0{\times}10^7$ CFU/mL). The optimal concentration of red ginseng starch and yeast extract as a medium were 20% and 10 g/L, respectively. Under these conditions, the cell mass of L. plantarum 15357 and L. mesenteroides sub sp. reached $5.11{\times}10^{10}$ and $8.17{\times}10^{10}$ CFU/mL. These results show a great possibility for the utilization of red ginseng starch as economic medium sources in the production of cell mass of lactic acid bacteria. This is the first trial of development of economic LAB growth medium using discarded red ginseng starch.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.2
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• pp.215-221
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• 2011

To establish an indoor-rearing system for the Large Copper butterfly, $Lycaena$ $dispar$ and the Small Copper butterfly, $Lycaena$ $phlaeas$, the effect of temperature, photoperiod and host plants on larval development was investigated. The larvae of $Lycaena$ $dispar$ fed on $Rumex$ $crispus$, whereas the larvae of $Lycaena$ $phlaeas$ ate both $Rumex$ $crispus$ and $Rumex$ $acetosa$. The duration of the larval period of $Lycaena$ $dispar$ was 13.8 days on $R.$ $crispus$ and that, of $Lycaena$ $phlaeas$ was 15.9 days and 15.2 days on $R.$ $acetosa$ and $R.$ $crispus$ respectively. Laboratory experiments show that the Large Copper larvae are able to feed on other $Rumex$ species without harming their overall survival and can utilize these alternative host plants at least as efficiently as their natural host plant. This result suggests that plant chemistry is not responsible for their lack of utilization of the alternative host plants in the wild. Host plant choice by ovipositing females was measured with the two alternative hosts. $Lycaena$ $dispar$ preferred $R.$ $crispus$ to $R.$ $acetosa$, wheareas $Lycaena$ $phlaeas$ preferred $R.$ $acetosa$ to $R.$ $crispus$. Temperature has been proposed as an important determinant of developmental rate, lifespan and mortality in invertebrates. As temperature increased, length of the developmental period gradually decreased. The developmental period of the Large Copper larvae was 11.0 days and 28.5 days at $30^{\circ}C$ and $17.5^{\circ}C$, respectively.

• Journal of Plant Biotechnology
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• v.37 no.2
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• pp.125-132
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• 2010

Rice is the staple food of more than 50% of the worlds population. Cultivated rice has the AA genome (diploid, 2n=24) and small genome size of only 430 megabase (haploid genome). As the sequencing of rice genome was completed by the International Rice Genome Sequencing Project (IRGSP), many researchers in the world have been working to explore the gene function on rice genome. Insertional mutagenesis has been a powerful strategy for assessing gene function. In maize, well characterized transposable elements have traditionally been used to clone genes for which only phenotypic information is available. In rice endogenous mobile elements such as MITE and Tos (Hirochika. 1997) have been used to generate gene-tagged populations. To date T-DNA and maize transposable element systems has been utilized as main insertional mutagens in rice. A main drawback of a T-DNA scheme is that Agrobacteria-mediated transformation in rice requires extensive facilities, time, and labor. In contrast, the Ac/Ds system offers the advantage of generating new mutants by secondary transposition from a single tagged gene. Revertants can be utilized to correlate phenotype with genotype. To enhance the efficiency of gene detection, advanced gene-tagging systems (i.e. activation, gene or enhancer trap) have been employed for functional genomic studies in rice. Internationally, there have been many projects to develop large scales of insertionally mutagenized populations and databases of insertion sites has been established. Ultimate goals of these projects are to supply genetic materials and informations essential for functional analysis of rice genes and for breeding using agronomically important genes. In this report, we summarize the current status of Ac/Ds-mediated gene tagging systems that has been launched by collaborative works from 2001 in Korea.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.31-38
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• 2011

This study was conducted to build frameworks for a guideline of community forest projects with respect to ODA of Korea (Official Development Assistant) in forest fields. Community forestry is a worldwide phenomenon which began in developing countries such as Nepal, Gambia, Guinea, and Indonesia and has been gradually recognized as an effective measure for ODA in forestry areas from ODA/DAC countries and the other international donors. This study investigated types of community forest status, mechanisms of community forest project conducted by ODA/DAC countries or the other international donors, and CFM (Community Forest management) success factors. As a result of our study, there are different types of resource users, having different economic and social status, perspectives, knowledge systems, values, understandings and objectives in community based forestry. Consequently, the clear forest tenure systems enabling communities to get motivated for the projects, the most appropriate agroforestry systems in different countries, capability of community to manage forest and etc must be considered carefully when the community forest project are implemented for ODA of Korea in order to gain successful results from ODA in forestry fields.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.577-596
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• 2018

ASEAN countries consist of vast coastal areas and thousands of islands that are vulnerable to the effects of climate change on sea level rise. It is believed that this will play an important role in reducing greenhouse gas emissions globally in order to minimize the damage suffered by ASEAN countries. To overcome this issue, biofuels have been used to minimize the impact on the environment by replacing fossil fuels and to reduce greenhouse gas emissions. In those cases of United States, Brazil and Europe, where biofuels are highly utilized, research, development and investment in this field have been actively conducted in the past. In ASEAN countries, however, it has not been a long time since the biofuel policies were established. To overcome this problem, we investigated the renewable fuel policy in the United States, Brazil and the European Union. Based on this, we suggested the utilization plan and prospect of biofuel policy in ASEAN countries.

• Journal of Advanced Navigation Technology
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• v.16 no.1
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• pp.89-95
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• 2012

This paper introduces domestic and international trends and researches related with U-Greenhouse systems. USN (Ubiquitous Sensor Networks), along with the development of networks as well as science and technology, is a new computing paradigm which is the convergence of user-oriented physical activity space and virtual space of electronics and computing and also provides services according to change in surrounding environment at anytime and anywhere. The U-Greenhouse system is to apply USN to agricultural production, logistics and distribution management which are relatively insufficient to utilize IT technology. Thus, applying u-IT technology to agriculture can reinforces international competitiveness of the agricultural sector through the effects such as cost cutting as a rise in output, logistics and distribution management.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.893-903
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• 2010

A cellulolytic and xylanolytic enzyme complex-producing alkalothermoanaerobacterium strain, Tepidimicrobium xylanilyticum BT14, is described. The cell was Grampositive, rod-shaped, and endospore-forming. Based on 16S rRNA gene analysis and various lines of biochemical and physiological properties, the strain BT14 is a new member of the genus Tepidimicrobium. The strain BT14 cells had the ability to bind to Avicel, xylan, and corn hull. The pH and temperature optima for growth were 9.0 and $60^{\circ}C$, respectively. The strain BT14 was able to use a variety of carbon sources. When the bacterium was grown on corn hulls under an anaerobic condition, a cellulolytic and xylanolytic enzyme complex was produced. Crude enzyme containing cellulase and xylanase of the strain BT14 was active in broad ranges of pH and temperature. The optimum conditions for cellulase and xylanase activities were pH 8.0 and 9.0 at $60^{\circ}C$, respectively. The crude enzyme had the ability to bind to Avicel and xylan. The analysis of native-PAGE and native-zymograms indicated the cellulosebinding protein showing both cellulase and xylanase activities, whereas SDS-PAGE zymograms showed 4 bands of cellulases and 5 bands of xylanases. Evidence of a cohesinlike amino acid sequence seemed to indicate that the protein complex shared a direct relationship with the cellulosome of Clostridium thermocellum. The crude enzyme from the strain BT14 showed effective degradation of plant biomass. When grown on corn hulls at pH 9.0 and $60^{\circ}C$ under anaerobic conditions, the strain BT14 produced ethanol and acetate as the main fermentation products.

• Korean Journal of Agricultural Science
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• v.42 no.2
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• pp.99-103
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• 2015

Potato virus T (PVT) is a plant pathogen in the family Betaflexiviridae, group IV single-stranded positive sense RNA viruses. The major host of PVT is potato, and it has been reported in Ullucus tuberosus, Oxalis tuberosa and Tropaeolum tuberosum. This study aimed at developing reverse transcription (RT)-polymerase chain reaction (PCR) and nested PCR techniques for specific detection of PVT. Finally, Two RT-PCR primer sets were developed and verified. The RT-PCR products were amplified to 734 (PVT RT-PCR primer set 6) and 828 bp (PVT RT-PCR primer set 29) long to detect PVT. The nested PCR primer sets [PVT-N70/C20 ($734{\rightarrow}315bp$) and PVT-N75/C30 ($828{\rightarrow}529bp$)] were developed which are high sensitivity and verification for detection of PVT. Furthermore, a modified-positive control plasmid is use to verify contamination of laboratory in PVT detection. This study supported the diagnose PVT in potato or PVT related hosts.