• Fire Science and Engineering
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• v.32 no.2
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• pp.7-16
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• 2018

In this study, the previous design fire curve for fire simulation was modified and re-suggested. Numerical simulations with the FDS and CFAST were performed for the n-heptane and n-octane pool fires in the ISO 9705 compartment to evaluate the prediction performances of the previous 1-stage and modified 2-stage design fire curves. The numerical results were compared with the experimental temperature and concentrations of $O_2$ and $CO_2$. The FDS and CFAST simulations with the 2-stage design fire curve showed better prediction performance for the variation of temperature and major species concentration than the simulations with 1-stage design fire curve. Especially, the simulations with the 2-stage design fire curve agreed with the experimental temperature more reasonably than the results with the 1-stage design fire curve. The FDS and CFAST simulations showed good prediction performance for the temperature in the upper layer of compartment and the results with the FDS and CFAST were similar to each other. However, the FDS and CFAST showed poor and different prediction performance for the temperature in the lower layer of compartment.

• Journal of agricultural medicine and community health
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• v.16 no.1
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• pp.79-89
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• 1991

A systematic study was conducted to identify and isolate a serologically pertinent antigen with high specific activity and low cross reactivity from Cysticercus parenchymal antigen. Differential centrifugation of the homogenate yield three particulate and one soluble fractions ; the $480{\times}G$ pellets($CyL_2$), the $7650{\times}G$ pellet($CyL_3$), the $100000{\times}G$ pellet($CyL_4$), and $100000{\times}G$ supernatant($CyL_6$). We compared antigenicity of these antigens to that or cystic fluid antigens($CyF_1$), saline extract of cystic wall($CyL_1$), and n-butanol treated $GyL_4$ antigen ($CyL_6$) based on SDS-PAGE and immunoblot techniques. The data obtained were as follows : 1) The ratio of O.D. value of ELISA against cysticercosis positive pool sera to that of negative pool sera was highest when using $CyF_1$ as antigen. However the ratio was relatively low in case of $CyL_{3.4}$ and $CyL_5$. 2) We have noted in previous paper that most strong antigenic activities are present in 63Kd band with low cross reactivities. An effective serologic reagent must contain components that are recognized by most infected sera. 63Kd band met this criteria and could be considered as a reliable band for the diagnosis of cysticercosis. As far as 63Kd band concern, $CyL_5$ showed most strong activities without disturbance of cross reaction by EITB in spite of low applicability to microplate ELISA. 3) $CyL_5$ could detect the serum antibody of cysticercosis even in very low titers, around cut-off values of microplate ELISA, by immunoblot. It also could detect the cross reactivities of Echinococcus species, which showed high absorbance value in micro plate ELISA and some sparganosis cases. Further purification of this antigen will be able to represents a antigen that can be used in the diagnosis of cysticercosis.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.142-149
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• 2010

Tadpole shrimps are aquatic crustaceans adapted to temporary water pool. Since they have been recorded as the living fossil, there are a number of reports on their past and present distribution as well as their morphology and reproduction in foreign countries. However, there are few studies of biology and ecology of tadpole shrimps despite registration as an endangered species by Ministry of Environment, in Korea. This study was carried out to examine the distribution and habitat characteristics of tadpole shrimps (Triops longicaudatus) collected from May 2006 to July 2008 in Korea. Tadpole shrimps were found from the paddy fields and ephemeral pools at 21 countries in South Korea. They appeared between May and July and survived for 30 days, and temperatrue range was $10.7^{\circ}C$ to $33.5^{\circ}C$. The average turbidity of experimental paddy fields was 176.8 (${\pm}239.3$) NTU, and controlled field was 28.9 (${\pm}26.7$) NTU. The life pattern of tadpole shrimps is adapted to a temporary water pool and unstable environmental conditions, and also there was great effect of agricultural activity on the development and growth of tadpole shrimps.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.320-333
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• 2016

This study was carried out to elucidate the development of unprecedented water-bloom caused by a single species of colonial green algae Eudorina elegans in the upstream area of the Seungchon weir located in the Yeongsan River from late April to May 2013. The Yeongsan River is typically regulated system and the waterbody is seriously enriched by both external and internal sources of nutrients. Seasonal algal outbreaks were highly probable due to various potential factors, such as the excessive nutrients contained in treated wastewater, slow current, high irradiation and temperature, in diatom (winter), green algae (spring) and bluegreen algae (summer). Spring green-tide was attributed to E. elegans with level up to $1,000mg\;m^{-3}$(>$50{\times}10^4cells\;mL^{-1}$). The bloom was exploded in the initial period of the algal development and after then gradually diminished with transporting to the downstream by the intermittent rainfall, resulting in rapid expansion of the distribution range. Although the pulsed-flows by the weir manipulation was applied to control algal bloom, they were not the countermeasures to solve the underlying problem, but rather there still was a remaining problem related to the impact of pulsed-flows on the downstream. The green-tide of E. elegans in this particular region of the Yeongsan River revealed the blooming characteristics of a colonial motile microalga, and fate of vanishing away by the succeeding episodic events of mesoscale rainfall. We believe that the results of the present study contribute to limno-ecological understanding of the green-tide caused by blue-green algae in the four major rivers, Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.32-32
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• 2019

Mutation breeding is the useful tool to improve agronomic traits in various crop species. Soybean is most important crop and is rich in protein and oil contents. Despite of the importance as economic value and various genetic resource of soybean, there have been limited studies of genetic relationship among mutant resources through radiation breeding. In this study, the agronomical phenotype for selecting various genetic resources was evaluated in 528 soybean mutant lines. As a result, 210 soybean mutants with their original cultivars were selected with various traits. We named 210 selected lines as Mutant Diversity Pool (MDP). The genetic diversity and the relationship of the MDP were investigated using TRAP and TE-TRAP markers. In TRAP analysis, sixteen primer combination (PC)s were used and a total of 551 fragments were amplified. The highest (84.00%) and the lowest (32.35%) polymorphism levels were showed in PC MIR157B+Ga5 and B14G14B+Ga3, respectively. The mean of PIC values was 0.15 ranging from 0.07 in B14G14B+Sa12 to 0.23 in MIR157B+Sa4. Phylogenetic and population structure analysis indicated that the 210 MDP lines dispersed to four groups among the wild types and their mutants. The highest genetic diversity among populations was observed between lines Paldal and 523-7 (Fst=0.409), whereas the lowest genetic diversity was between population KAS360-22 and 94seori (Fst=0.065). AMOVA showed 11.583 (21.0%) and 43.532 (79.0%) variations in inter and intra mutant population, respectively. Overall, the genetic similarity of each intra mutant populations was closer than that of inter mutant population. A total of 408 fragments were amplified in the 210 MDP using twelve PCs of TE-TRAP markers that were obtained from a combination of three TIR sequence of transposable elements (MITE-stowaway; M-s, MITE-tourist; M-t, PONG). The highest (77.42%) and the lowest (56.00%) polymorphism levels were showed in PONG+Sa4 and PONG+Sa12, respectively. The mean of PIC values was 0.15 ranging from 0.09 in M-s+Sa4 and M-s+Ga5 to 0.21 in M-t+Ga5. AMOVA of M-s showed 2.209 (20%) and 8.957 (80%) variations in inter and intra mutant population, respectively. AMOVA of M-t showed 2.766 (18%) and 12.385 (82%) variations in inter and intra mutant population, respectively. AMOVA of PONG showed 3.151 (29%) and 7.646 (71%) variations in inter and intra mutant population, respectively. According to our study, the PONG had higher inter mutant population and lower intra mutant population. This mean was that for aspect of radiation sensitivity, M-s and M-t showed higher mobility than that of PONG. Our results suggest that the TRAP and the TE-TRAP markers may be useful for assessing the genetic diversity and relationship among soybean MDP and help to improve our knowledge of soybean mutation/radiation breeding.

• Korean Journal of Ichthyology
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• v.32 no.1
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• pp.1-7
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• 2020

Investigations of distribution status and extinction threat evaluation of the Korean endemic species, Iksookimia yongdokensis were undertaken from 2017 to 2018. Among the 22 streams and 97 sampling sites investigated during the study period, samples of I. yongdokensis were collected from 9 streams at 37 sites (from Daejongcheon Stream of Gyeongju-si to Songcheon Stream of Yeongdeok-gun). The appearance of I. yongdokensis was relatively common in streams such as Hyeongsangang River (15 stations), Yeongdeok Oshipcheon Stream (4 stations), Gokgangcheon Stream (4 stations), Chuksancheon Stream (3 stations) and Daejongcheon Stream (3 stations). The main habitat of I. yongdokensis was in pools on flat-land in streams of clean water with slow velocity, and with pebble, gravel and sand bottoms. Previous records of the appearance of I. yongdokensis, indicate they were first seen at seven stations including Jangsacheon Stream, but they were not present in Songcheon Stream. Compared to our results there is evidence as noted for a 38.9% reduction in occupancy within 3 generations (10.5 years), and a decline inhabitat quality. Therefore, I. yongdokensis is now considered vulnerable (VU A2ace) based on the IUCN Red List categories and criteria. The main reasons for the decline were assumed to be dry weathering in the river, the introduction and diffusion of exotic fish species Micropterus salmoides, and river refurbishment project.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.4
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• pp.310-321
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• 2016

This study describes the spatial distribution of dinoflagellate cyst assemblages from the fishing ports along Jeju Island. Surface sediment samples from 22 stations revealed the occurrence of 29 species involving the Groups Protoperidinioid (44.8%), Gonyaulacoid (31.0%), Calciodineloid (10.3%), Gymnodinioid (6.9%), Diplosalid (3.5%) and Tuberculodinioid (3.5%). The cyst abundance recorded here is very low ($13{\sim}220cysts\;g-dry^{-1}$) as compared to Korean coastal regions. The abundance of heterothophic cysts increased in several fishing pots with fine sediments and anthropogenic tidal pools. And cyst abundance was well correlated with the grain-size composition of surface sediments. The dinoflagellate cyst assemblages in Jeju fishing ports were characterized by the dominant species, cyst of Gymnodinium sp., cyst of Pyrodinium bahamense and cyst of Scrippsiella trochoidea in 2012, Protoperidinium sp. (Brigantedinium sp.), cyst of Scrippsiella sp./trochoidea and cyst of Gymnodinium sp. in 2014, and Protoperidinium sp. (Echinidinium sp. and Brigantedinium sp.) in 2016. The advent of the toxic dinoflagellate, Pyrodinium bahamense were recorded for the first time in Jeju coastal waters. As a results, we are determined should be to monitoring and management measures for new toxic dinoflegallates from tropical or subtropical reigions and anthropogenic tidal pools by industrial activities.

• Journal of Life Science
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• v.25 no.11
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• pp.1244-1254
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• 2015

Naturalized plants were identified and recorded in Busan city based on field surveys and related literature. These plants consisted of 156 taxa in total, belonging to 31 families, 95 genera, 147 species, and 9 varieties. The Compositae had the highest diversity among 31 families, with 44 taxa, followed by Gramineae, with 24 taxa, and Leguminosae, with 10 taxa Among the plants, 68.6% (107 taxa) were annuals and biennials, and 30.1% (47 taxa) were perennials. There was one shrub (Amorpha fruticosa) and one tree (Robinia pseudoacacia). Naturalized degree 5 plants, as common and abundant plant, founded 26 taxa (96.3%) were most highly ratio from Korean naturalized plants. According to the results of the analysis based on place of origin, 50 (32.1%) taxa were from Europe, and 48 (30.8%) taxa were from North America. Epecophyten was the most common of the naturalized plants, with 123 taxa Sixty-six (42.3%) taxa were introduced during period 1, and 15 (9.6%) were introduced during period 4. Ergasiophygophyten (50.6%) and Kenophyten (32.1%) were the dominant plants in these introduction periods. In conclusion, Busan city acts as a conduit for the introduction of naturalized plants. A sustainable management and monitoring strategy may be needed to prevent the introduction and naturalization of plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.1
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• pp.45-64
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• 2014

This study was carried out to offer the ecological data for restoring and maintaining a local stream by analyzing the vegetation and flora in Geumsan Stream and Gisa Stream, Geumsan-gun, Chungcheongnam-do, Korea. As a result of comparison of realities of land use near Geumsan Stream and Gisa Stream, in Geumsan Stream, the ratio of residential areas, commercial and business places, and places of transportation facilities was high. With these types of land use aggregating densely in the center, farmlands were formed on both sides. On the other hand, in Gisa Stream, farmlands were distributed evenly in all sections. As a result of comparison of flora of the two streams, Geumsan Stream had a total of 166 taxons including 53 families, 131 genuses, 139 species, 23 varieties, and 4 forms, and Gisa Stream had a total of 142 taxons including 42 families, 111 genuses, 116 species, 21 varieties, and 5 forms. As a result of calculation of the Naturalization Index and Urbanization Index, the indices were analyzed to be 23.5% and 12.1% in Geumsan Stream and to be 21.8% and 9.7% in Gisa Stream, respectively. Hence, Geumsan Stream showed higher figures in both evaluation indices than those of Gisa Stream. In addition, as a result of calculation of the Actual Urbanization Index, which is the index supplemented by considering the species pool and area, it could be known that Geumsan Stream (0.0285) was urbanized more than Gisa Stream (0.0107) by about 2.7 times. A total of 18 plant communities were classified in Geumsan Stream and Gisa Stream. In Geumsan Stream, 14 vegetation types were identified, and it was analyzed that there are various vegetation types including Phalaris arundinacea community, Zoysia japonica community, Phragmites japonica-Phalaris arundinacea community, etc. evenly distributed. 11 vegetation types were identified in Gisa Stream, and it was examined that Phragmites japonica community is widely distributed in all sections.

• Korean journal of applied entomology
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• v.60 no.3
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• pp.323-329
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• 2021

This study investigated the seasonal distribution of ticks in Boeun, Chungbuk, South Korea, from 2016 to 2020. Over the five-year period, ticks were collected annually from four different sites. A total of 17,704 ticks belonging to three tick species (Haemaphysalis longicornis, Haemaphysalis flava, and Ixodes nipponensis) were collected. H. longicornis was the dominant species across all four sites with the highest density of 68.40% of the total collected specimens, followed by H. flava (3.53%) and I. nipponensis (0.06%). The larvae of unidentified species were also collected: 11.81 T.I. (28.01%). The H. longicornis population peaked during the spring season (May-June), whereas the larval population peaked during August and September. H. longicornis was collected the most from four sites (coniferous forest, broad-leaf forest, mountain path, and copse), with the exception of the larvae, which was collected the most in grassland and grave. H. flava was collected from all sites, but in a small proportion. The SFTS virus was not found in any of the 828 pools of ticks during 2016-2020. Based on the results of this study, the continuous surveillance of the tick population is recommended to mitigate the spread of diseases by these vectors.