• Animal cells and systems
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• v.10 no.1
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• pp.15-20
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• 2006

Allergic inflammation is thought to be a Th2 cell-dominant immune response during which tissue-resident fibroblasts produce chemokines which contribute to the recruitment of migratory leukocytes to sites of tissue injury. Thymus and activation-regulated chemokine (TARC; CCL17) is a potent member of the CC chemokine family and a selective chemoattractant for Th2 cells. In order to study the regulatory profiles of TARC production by $TNF-{\alpha}$, $IFN-{\gamma}$, and Il-4 in human normal skin fibroblast, CCD-986sk cell line was used. The expression of TARC protein was measured using ELISA, and mRNA level was detected by RT-PCR. The combination of $TNF-{\alpha}$ and IL-4 induced a time-and dose-dependent synergistic increase in the expression of TARC at both protein and mRNA levels in the cultured human skin fibroblasts. Exposure of the cells to single cytokine had no effect on TARC expression. The high concentration (100 ng/ml) and long incubation time (72 h) of $IFN-{\gamma}$ further enhanced the TARC production induced by $TNF-{\alpha}$/lL-4 in the skin fibroblast. This synergistic effect of Th1 and Th2 type cytokines on TARC production by skin fibroblasts may contribute to the inflammatory cell infiltration and tissue damage with allergic inflammation.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.235-243
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• 2001

Genetic variation of the beet armyworm, Spodoptera exigua (Hubner), was analyzed by polymorphic allozymes. Field populations were subdivided by different hosts, geographical locations, and seasons. Estimated average heterozygosity ($0.443\pm$0.013) indicated high genetic variation in all field populations of S. exigua. There were significant inbreeding effects deviated from Hardy-Weinberg equilibrium in each of subpopulations. These significant nonrandom matings were caused by within-subpopulations probably due to sampling errors, but not by mating isolation among subpopulations. Wrights ($F_{ST}$ ) and Neis (D) genetic distances indicated little genetic differentiation among subpopulations, though some southern local subpopulations (Haenam and Sachon) were relatively different of northern subpopulations (Andong and Kunwi). Estimated number of migrants per generation was 5.9 among host subpopulations, 10.6 among geographical subpopulations, and 31.8 among seasonal subpopulations. These genetic analyses suggest that Korean S. exigua subpopulations have little genetic differentiation mostly due to their significant migratory capacity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.361-370
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• 1982

The effects of climatic factors on organisms lire variable and complex, and it, however, can be interpreted in terms of those on the distribution and those on the population densities. The distribution of an organism may largely be determined by the temperatures, except some temporal organisms which are depended on the air mass movements. Population density of an organism is determined by various climatic factors, such as previous winter temperature, temperature of growing season and rainfall. The start of growing season of the rice plants has been shifted to earlier since last decade in Korea. This may mean that the overall climatic condition during the growing season might be considerably different from those in past years, and such a difference in climatic conditions might have close relation with the recent status of the diseases and insect pests through direct effects on the physiology and population dynamics of the organisms, as well as through on the biotic associations of the pest organisms. The white back planthopper and brown planthopper have become the key insect pests in Korea in recent years. They are migratory and have high reproductive pontentials and more generations than average residential insects. The synchronization of the migrants and physiological condition of the rice plants seems to be the important factors in relation to the recent outbreaks of these insects; the high reproductive rate can be obtained with the growth stage of rice being 30-50 days after transplanting. The modication of the microclimate associated with high plant density and some other introduced new cultural techniques also have some relation with the outbreak. The key diseases of the rice are the blast disease, sheath blight and the bacterial leaf blight. For the rice blast, the seedling blast and leaf blast during the early growing season and the neck blast, have become more serious, the former may be related to hotbed nursery and the later may be related to the high humidity in early August, and synchronization of the heading time which has been shifted to early part from middle or late part of August. In general, for the rice diseases, the development of the new races have been the most serious which are largely resulted from the introduction of the new varieties, but it also seems to be related with the prolonged periods of the favorable condition associated with the shifted growing seasons. In general, the diseases and insect pest problems have become much more variable and complex, and control measures should be based on the thorough knowledge of the ecology of the pest organisms, that is, effects of various environmental factors on the disease cycle; spore release, spore deposition, infection, colonization and sporulation of the disease organisms, and those on the development, reproductive potentials, dispersal, age specific responses of the insects. The well organized real-time pest management systems, such as alfalfa weevil management system developed at the Purdue University in U.S., is the prime importance for the implementation of the pest management principles.

• Journal of Climate Change Research
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• v.2 no.1
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• pp.1-14
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• 2011

In order to identify the current state of the $CO_2$ concentrations at the Gosan site in Jeju, the data from the Gosan station was compared with the ones from domestic and foreign sites registered in the World Data Centre for Greenhouse Gases(WDCGG). As a result, the $CO_2$ concentrations in the Asian region including Gosan site were higher than in the other continents, which can be explained that the $CO_2$ emissions in the Asian region have been rapidly increasing due to the recent economic growth. In comparison with ther Asian-Pacific sites (i.e., Ryori, Waliguan, and Mauna Loa), Gosan site showed the highest $CO_2$ concentrations because this site can be easily affected by China emissions. With the trajectory analysis and the ratios of air pollutants, we found that the high concentrations of Gosan site in January were mainly caused by the long-range transport from China, while in August the high concentration in the night time by the stagnation and the active plant respiration. Also, in May and November it occurred as the polluted air from China was transported with migratory cyclone.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.49-59
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• 2022

Total of 325 estuaries in Korea were surveyed to analyze the effect of presence of sluice gate on the estuary environment and fish community from 2016 to 2018. Fish community in closed and open estuaries showed differences generally, and the relative abundance (RA) of primary freshwater species in the closed and migratory species in the open estuaries were high. The result of classifying species by habitat characteristics in closed and open estuaries showed similar tendencies at the estuaries of south sea and west sea. The relative abundances of primary freshwater species in the closed estuaries at the estuaries of south sea and west sea were the highest, but estuarine and migratory species were high in both closed and open estuaries at the estuaries of east sea. Primary freshwater species showed higher abundances in the closed estuaries with reduced salinity due to blocking of seawater since they are not resistant to salt. However, primary freshwater species in open estuaries at east sea was higher than that of the closed estuaries, which is considered to be the result of reflecting the characteristics (tide, sand bar, etc.) of the east sea. Korea Estuary Fish Assessment Index (KEFAI) was showed to be higher at open estuaries than closed in all sea areas (T-test, P<0.001), the highest KEFAI was observed in closed estuaries at south sea, and open estuaries in east sea. Fish community of closed and open estuaries in each sea areas showed statistically significant differences (PERMANOVA, East, Pseudo-F=3.0198, P=0.002; South, Pseudo-F=22.00, P=0.001; West, Pseudo-F=14.067, P=0.001). Fish assemblage similarity by sea areas showed a significant differences on fish community in closed and open estuaries at east sea, south sea, and west sea (SIMPER, Group dissimilarity, 85.85%, 88.36%, and 88.05%). This study provided information on the characteristics and distribution of fish community according to the types of estuaries. The results of this study can be used as a reference for establishing appropriate management plans according to the sea areas and type in the management and restoration of estuaries for future.

• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.113-122
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• 2014

This study was conducted to clarify the community characteristics of wintering waterbirds in Geum River from September, 2011 to March, 2012 (1st) and from September, 2012 to March, 2013 (2nd). 63 species of waterbirds including raptors were observed during the survey. 50 species of 188,673 individuals recorded during the first survey, and 56 species of 116,611 individuals were recorded during the second survey. The dominant species was high dominance dabbling ducks by Baikal Teals, Mallards, Spot-billed Ducks, Greater White-fronted Geese, Black-tailed Gulls and Common Shelducks. We classified the wintering waterbirds into 9 taxa based on the similar ecological characteristics and analyzed the correlation with temperature. As a result, dabbling ducks, diving ducks and raptors showed positive correlation and herons and waders showed negative correlation. Geese, swans and dabbling ducks were high habitat utilization ratio at the Geumgang estuary barrage upstream area, and diving ducks, herons, waders and gulls were high habitat utilization ratio at the Geumgang estuary barrage downstream area.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.264-272
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• 2015

Understanding bird status is essential for the systematic and sustainable management of the Nakdong River Estuary, taking into consideration the relationship between ecosystems and the bird species. In this study, bird status in the Nakdong River Estuary Bird Sanctuary prior to the Four Major Rivers Project was analyzed using the bird monitoring data (2003-2011) from surveys conducted by the Busan Development Institute. The high percentage of winter visitors in terms of both species diversity (38.36%) and individual bird numbers (63.14%) suggest that the Nakdong River Estuary is an important wintering site for migratory birds. Cumulative numbers of individual birds were higher in Myungji (208,601), West Nakdong River (202,444), Eulsukdo (153,232), and Baekhap Doyodeung (150,595). The total numbers of migratory species were higher in Eulsukdo (171), Ilungdo (124), Myungji (132), and Samrak (121). Among the 232 species found in the Nakdong River Estuary, Anas platyrhynchos (17.71%) was the most common species, followed by Anas poecilorhyncha (8.85%), Larus crassirostris (6.48%), Anser fabalis (6.09%), Anas penelope (5.16%), and Calidris alpina (4.22%). Most bird taxa, except shelducks, showed annual fluctuations in individual numbers, with increasing frequency during survey periods. Of these, cormorants, swans, and gulls showed higher fluctuations than other taxa. Swans decreased drastically in numbers in 2007-2008 and 2009-2010 compared to previous years. Shore birds, gulls, wagtails, and other forest birds were also less common in 2010-2011. These results suggest that there were some environmental changes that might have affected the birds in the Nakdong River Estuary. Overall, the results suggest that habitat types affect the distribution of dominant species.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.59-66
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• 2011

For the improvement of productivity of beekeepers and to develop new management strategy through the analysis of current honeybee-keeping management types and evaluation of related skills and basis in Korea were surveyed. The serial surveys were carried out in 2008 for a total of 253 beekeepers from different localities in Korea. The results revealed that 145.9 colonies of honeybee were managed by each beekeeper in Korea. The beekeepers group who were younger than 55 years possessed 191.7 colonies. The older age group of beekeepers kept rather smaller number of colonies. The career groups over 15 years in apiculture were keeping 176.0 colonies in average. The numbers of bee colonies were not significantly different among localities and educational backgrounds. The migratory apiaries with 145.9 hives were dominant than those fixed ones with 83.0 (p<0.01). It was observed that 57.8% of apiaries were located in the vicinity of farmer's house, whereas 30.3% were managed in mountain area; however older group (65.4%) preferred to keep it near their houses (p<0.05). The proportion (35.7%) of part-time fixed apiary was the highest among four apiary management types. The younger group and high career group operated full-time migratory apiary (38.8% and 40.3%) (p<0.05), respectively. However, the older group and low career group preferred as part-time fixed one (43.2% and 46.6%), respectively (p<0.001). There was no significant difference among localities. The surveyed beekeepers produced propolis, commercial colonies, pollen, royal jelly, and pollination hives in addition to honey. The group of less than 15 years career and mountain apiary mainly produced propolis and pollen. However, those who dwell in small and middle areas mainly produced propolis and commercial colonies. The levels related to beekeeping skills and basis were evaluated as intermediate from 3.11 and 2.86 points on 5 points scale, respectively. More careered group having skill level of 3.33 point and basis level of 3.02 showed higher levels than less careered one. The levels of skill and basis evaluated from age groups and localities were similar with each other with no significance.

• Journal of Environmental Impact Assessment
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• v.32 no.6
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• pp.389-406
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• 2023

The research area, located in the northern coastal region of South Korea's West Sea, involves three bird habitats. Among these are two newly established habitats in Songdo International Business District, created by filling and developing tidal flats that were previously utilized as stopover sites for migratory birds. One of these areas showed decrease (Residual tidal flats, site.1) while the other showed increase (Artificial lake, site.2) in bird influx. The third habitat (Namdong reservoir, site.3) is a pre-existing stable habitat which has been maintained as a stable habitat. This study conducts an assessment of habitats based on avian population clusters and environmental surveys and proposes habitat management measures. A survey of bird populations and habitat environments was conducted for a total of 39 occasions from January to December 2022. The observed bird species totaled 14 families and 48 species with 20,760 individuals. Compared to the existing habitats, the newly established habitats showed relatively lower influx of bird species and individuals. During the habitat assessment, the newly established habitats were rated as I to II grade, while the existing habitat was rated as relatively high III grade on the grading assessment of the tidal flat. An analysis of habitat types revealed that the existing habitat, in which diverse strategies for habitat type diversity and mitigating anthropogenic interference were demonstrated, attracted a diverse range of bird species. Through this research, it was deduced that the diversity of habitat types plays a significant role in attracting various bird species. Upon evaluation of habitat types concerning the habitat characteristics of the bird species selected for habitat management, as habitat management measures, it is deemed that the creation of shielded green areas (referred to as 'buffer green') to minimize interference from the surroundings, the establishment of reed fields (site.1, 2) positively correlated with reservoirs, and the improvement of sandbanks (site.1) positively associated with tidal flats, the two relations which we drew from correlation analysis between occurrence species and habitat types, would contribute to the future restoration and maintenance of stable habitats. The results of this study can be applied not only to the study area but also to other development zones, such as coastal reclamation sites, which share similar geographical and environmental characteristics, including arrival sites for migratory birds.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.103-109
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• 2007

To investigate the effects of artificial vegetation island (AVI) on fish distribution, we compared fish fauna from artificial vegetation island (AVI) area, which installed in 2000, natural vegetation area (NVA) and vegetation-free area (VFA) at Kyungan Stream area of Lake Paldang from Jul. to Nov., 2005. Results showed that 11 families 23 genera 24 fish species were distributed in the AVI and NVA. Squalidus japonicus coreanus, a small-size fish which generally lives at the downstream, dominated absolutely in the individual numbers. However, only 6 families 11 genera 12 species of fishes caught at the VFA, and dominant fishes were Hemibarbus labeo and Erythroculter erythropterus, a medium to large-size migratory fishes which live in mid-depth of water column. The dominance index was high at the AVI (0.778) and NVA (0.868), whereas the diversity index and evenness index were high at the VFA. Fish distribution at AVI was similar to that of the NVA in numbers of species, indicating that the AVI could playa role as spawning and inhabitation zone to a variety of fishes. We believe that AVI may be used for a restoration of the damaged and disturbed littoral ecosystem.