• Title/Summary/Keyword: dominant period

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Characterization of Biogenic Amine-Producing Microorganisms Isolated from Myeolchi-Jeot, Korean Salted and Fermented Anchovy

  • Mah, Jae-Hyung;Ahn, Jun-Bae;Park, Jong-Hyun;Sung, Ha-Chin;Hwang, Han-Joon
    • Journal of Microbiology and Biotechnology
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    • v.13 no.5
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    • pp.692-699
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    • 2003
  • The changes of physicochemical and microbiological states of Myeolchi-jeot, a Korean salted and fermented anchovy, were investigated during 20 days of storage at $4^{\circ}C,\;15^{\circ}C,\;and\;30^{\circ}C$. A total of 314 bacterial strains isolated from Myeolchi-jeot samples at different time intervals were identified, and their abilities to produce biogenic amines were determined by both decarboxylating agar media and HPLC analysis. The salinity and water activity of Myeolchi-jeot changed little, while the pH increased slightly over 20 days at the tested temperatures. A significant increase of total plate count was observed in the sample stored at $30^{\circ}C$. Staphylococcus spp. were dominant in Myeolchi-jeot, and its amine productivity was very weak. Bacillus spp. appeared increasingly with the progress of storage at all temperatures tested, and the increase was considerably dependent on the increase of storage temperature. Also, 58-73%, 83-90%, 81-90%, and 83-93% of Bacillus strains had the ability to produce histamine, tyramine, putrescine, and cadaverine, respectively. Therefore, the main amine producer in Myeolchi-jeot stored for a long period seems to be the genus Bacillus, especially B. licheniformis.

ENHANCED ARCTIC PRIMARY PRODUCTIVITY FOLLOWING SEA ICE RAPID DECLINE

  • Comiso, Josefino C.
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.1019-1022
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    • 2006
  • Satellite sea ice data from 1978 to the present reveal that the perennial ice (or ice that survives the summer) has been rapidly declining at almost 10% per decade. Warming due to increases in greenhouse gases in the atmosphere is now also being reflected in winter with drastic reductions in the maximum extent observed in 2005 and 2006. The retreat of the perennial ice also exposes more open water and has revealed an asymmetric distribution of chlorophyll a pigment concentration in the Arctic basin. Phytoplankton blooms are most dominant at high latitudes, partly on account of sea ice, but in the Arctic basin, it appears that pigment concentrations in the Eastern (Laptev Sea) Region are on the average three times higher than those in the Western (Beaufort Sea) Region. Such asymmetry suggests that despite favorable conditions provided by the melt of sea ice, there are other factors that affects the productivity of the region. The asymmetry is likely associated with much wider shelf areas in the East than in the West, with sea ice processes that inhibits the availability of nutrients near the surface in deep water regions, and river run-off that affects nutrient availability. The primary productivity in the pan-Arctic region have been estimated using the pigment concentrations and PAR derived from SeaWiFS data and the results show large seasonal as well as interannual variability during the 1998 to 2005 period. The data points towards increasing productivity for later years but with only 9 years of data it is too early to tell the overall effect of the sea ice retreat.

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Symbolic Violence of the Native Speaker Fallacy: A Qualitative Case Study of an NNES Teacher

  • Choi, Soo-Joung
    • English Language & Literature Teaching
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    • v.15 no.3
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    • pp.33-57
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    • 2009
  • Taking the issues of inequity and power between NES and NNES teachers as a starting point, this qualitative study explores the way the widespread belief of the native speaker fallacy manifests itself in one NNES teacher's teaching life and is linked to the teacher's understanding of herself as an English teacher. Guided by critical applied linguistics (Pennycook, 2001) and using Bourdieu's (1991) theorization of symbolic violence, I conducted an instrumental case study (Stake, 1995) in an ESL writing class at a US university. I collected data through classroom observations and interviews over a nine-month period and analyzed the data using the constant comparison method (Glaser and Strauss, 1967). The findings illustrate the ways the dominant ideology of the native speaker fallacy works to maintain and reproduce the status quo unequal relation between NES and NNES teachers by making all parties involved believe in the artificial sociocultural arrangements that favor NES teachers as legitimate. The findings direct our attention to the importance of critical teacher education that will enable future TESOL professionals to engage in critical reflection on diverse issues and envision transformative change. The findings, in particular, point to the need for language support for NNES teachers in TESOL teacher education.

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The building form of Myonang-jong and Its Regional Character (담양 면앙정의 건축형태 -호남지역 건축의 지역성 형성에 대한 소고-)

  • Kim, Dong-Uk
    • Journal of architectural history
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    • v.9 no.3 s.24
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    • pp.23-36
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    • 2000
  • The bureaucrat-scholars, ruling class of the Choseon Dynasty, used to build small private pavilions for rest and study for themselves. In the early period of the Dynasty, the pavilions had plain shapes with rectangular plan and simple wooden structure without any walls so as to enjoy the surrounding scenery. From the 16th century, the building form began to change into some diverse one by putting in an ondol room, an unique floor heating equipment. The pavilions also began to show regional differences by placing the ondol rooms in the floor. Myonang-jong, a pavilion occupied by a famous bureaucrat-scholar Song Soon, was built at Damyang of the southwest part of the Korean peninsula, so called Honam area, in 1533. At first, the building form followed the ordinary early pavilion shape using simple wooden structure and wooden floor. But when it was rebuilt in 1654 after burning down by war, there happened some changes. An ondol room was put in the center of the floor, of which regarded as a dominant regional characteristic of the Honam area. The change of the building form of Myonang-jong showed that it was the 17th century Honam area got the regional characteristic in the architecture of pavilion.

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Distributional Ecology Of Planktonic Diatoms In The Strait Of Georgia, B. C.

  • Shim, Jae Hyung
    • 한국해양학회지
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    • v.12 no.1
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    • pp.13-32
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    • 1977
  • In order to determine the distributional ecology, and to investigate factors influencing these features, the diatom communities in plankton at depths of one, twenty-five, fifty, and seventy five meters in the area were studied and measured over a fifteen month of period. Measurements of environmental factors including temperature and salinity and algal nutrients such as phosphate, silicate, nitrate, and ammonia were also made at the same depths and locations. The results indicate that the size of diatom communities and the species population changes were heavily dependent upon to season and location parameters as well as nutrient concentrations and hydrographic factors. Major factors influencing population distributions varied with principal species responsible for dominant species and species sucession. Two distinct distributional patterns in total diatom crop were observed in the study area. Maximum standing crop observed during spring and/or summer were related to the concentration of nutrients available at the onset of the spring bloom on a large scale. On a small scale, however, the distributions of total diatom standing crops were significantly correlated with both season/location factors and with hydrographic parameters as well. Vertical stratification of diatoms was observed only in the presence of the thermocline in the water column. Within the study area there was some seasonal consistancy in the composition of the species groups. However, some species association in these environments may vary with the change of season.

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Effects of Water Level Change on Wetland Vegetation in the Area of Riparian Forest for Dam Construction Period -Focused on the Hantan River Dam- (댐 건설 기간 수위변화가 하반림 일대 습지 식생에 미치는 영향 -한탄강댐을 사례로-)

  • Park, Hyun-Chul;Lee, Jung-Hwan;Lee, Gwan-Gyu
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.76-84
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    • 2014
  • This study was performed to monitor the effects of water level change on changes of landscape, vegetation community, and species diversity of riparian forest. Hantan river dam, study area, has been constructed in the area of Chansoo-myeon, Pocheon-si and Yeoncheon-eup, Yeoncheon-gun, Gyeonggi-do, which is a dam for flood control only in flooding season. Landscape changes were notable after the construction of coffer dam, and the changes were caused by water level increase in areas of riparian forests which consisted of mainly withered willow as a dominant species in the flooding season. It changed vegetation communities of riparian forest from Phragmites japonica and Salix koreensis to Phragmites japonica. Species diversity index was lowest in 2010 when the coffer dam was constructed and showed an increasing trend later. Thus, this study is well in agreement with a previous report that plants of the genus Salix wither by muddy water during flooding and also suggests, controlling water level of river and prediction of water level change's effects should be considered when any facilities are planned.

Pathogenic bacteria causing rot in commercial soybean sprout cultivation

  • Yun, Sung-Chul;Kim, Yong-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.2
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    • pp.113-119
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    • 2003
  • Soybean sprout pathogenic bacteria were isolated from the large, deep containers of a commercial factory. Over a period of one year, 40 pathogenic-like bacteria were isolated among a total of 732 isolates. In addition to bacteria previously reported to be associated with rotting, such as Pseudomonas putida and Erwinia carotovora, several other genera were also identified: Acinetobacter spp., Chryseobacterium spp., Klebsiella sp., Pantoea agglomerans, Bacillus sp. Fatty acid methyl ester (FAME) analysis using the Microbial ID (MIDI) system, and 16s rRNA sequence analysis, yielded identical results, confirming the identities of these microorganisms. Several types of selective media were not good for identification and determination of population structure in commercial environments, as colony type was not specific to the genus. There was no dominant bacterium, and we were not able to find the main bacterium responsible for soybean spout rot. Even though we did not identify a major target for controlling rot or screening for resistant cultivars, the results of this study indicated that bacterial rot of soybean sprout is endemic. In addition, it emerged that factory epidemics in summer are not caused by the bacteria isolated in this study.

Late Quaternay Paleoceanography as Recorded by Planktonic Foraminifera in the Ulleung Basin, East Sea

  • Kim, Gil-Young;Kim, Dae-Choul;Shin, Im-Chul;Yi, Hi-Il;Kim, Jeong-Chang
    • Journal of the korean society of oceanography
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    • v.33 no.1-2
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    • pp.8-17
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    • 1998
  • Paleoceanographic history of the East Sea is reconstructed based on several environmental parameters (coarse fraction content, planktonic foraminifera/benthic foraminifera ratio, fragmentation and assemblages of planktonic foraminifera, and coiling ratio of Neogloboquadrina pa-chyderma, etc,) of the late Quaternary sediments obtained from the Ulleung Basin. N. pa-chydeyma and Globigerina bulloides are dominant species (greater than 90% in abundance)among the total planktonic foraminifera assemblages in the late Quaternary sediments. The benthic foraminifera rarely occurred throughout the cores. Sinistrally-coiled specimens of N. pa-chyderma representing cold water temperature are observed more abundantly than dextrally-coil-ed ones. In addition, the sinistrally-coiled N, pachydeyma showed more the amount at the lower part of the cores than at the upper part suggesting the restriction of the Tsushima Warm Current into the East Sea during glacial period. G. bulloides, a species representative of upwelling condition, shows more abundant occurrence in the sediments of Core 941013 than those of Core 941006. This implies that Core 941013 is more influenced by upwelling than Core 941006. The upper part of the two cores contain more fragmentation of planktonic foraminifera suggesting significant dissolution by corrosive bottom wafer. Ascending CCD also played an important role for the absence of planktonic foraminifera at the upper part of the cores.

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Community Structures of Macrobenthos in Chonsu Bay, Korea

  • Lee, Jae-Hac;Park, Heung-Sik
    • Journal of the korean society of oceanography
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    • v.33 no.1-2
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    • pp.18-27
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    • 1998
  • Based on 53 quantitative samples collected in April (23 stations) and August (30 stations) of 1993, the species composition, distribution and abundance of macrobenthic invertebrates and bottom characteristics in Chonsu Bay were conducted. Bottom sediments consisted of mud at the close to the dyke, sandymud in the central bay, and coarse sand in the mouth of the bay. A total of 273 species (177 species in April and 200 species in August) were identified. Mean density per sampling station was 480 ind./m$^2$ in April and 1126 ind./m$^2$ in August, respectively. Number of species and densities decreased in the northern part of the bay. The macrobenthos showed a temporal difference in species composition, range of distribution, and community delimitation caused by larval settling. Although during the settling period in summer, large numbers of juveniles added in most of regions, unrelated to environmental conditions, but, successful recruitment may has been a rare event locally Theora fragilis (bivalve), Lumbrineris longifolia(polychaete), Neptys oligobranchia (polychaete) were numerically dominant, but their densities varied seasonally. Community structures of macrobenthos in Chonsu Bay were affected by several bottom environmental conditions, related to tidal current speed, regionally.

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우리 나라 중소기업의 전략변화와 기술능력 학습 - 우리나라 전자부품 산업에 대한 사례연구 -

  • 이병헌;김영배
    • Proceedings of the Technology Innovation Conference
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    • 1998.06a
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    • pp.57-90
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    • 1998
  • This study attempts to explore the evolution paths of Korean SMEs'strategies and their technological teaming processes. Several different evolution paths are identified based on a dynamic strategic group analysis of 115 SMEs'strategy in the Korean electronic component industry for the period of 1990-1995. Further, inadept case analyses on technological learning processes in 5 firms are undertaken. Major findings of this study can be summarized as follows : 1) There are three dominant evolution paths in SMEs'strategy. First path indicates the evolution from a subcontractor or petty imitator group(a strategic group with the narrow product/market domain and the low level of accumulated resource/capabilities) into an innovator group(a strategic group with the narrow domain but high level of technological capability) by accumulating technological capabilities. Second, some firms move from a subcontractor group into a generalizer group(a strategic group with broad product/market domain but relatively low level of technological capability) by simply adding product lines. Third path involves firms which evolve from a subcontractor group into a production focus group(a strategic group with high level of production capability) by investing in production capabilities. 2) An in-depth case analysis shows those who succeeded in technological learning are managed by CEOs, who have technological expertise and strategic vision, and have made an effort to establish management practices to support innovation, such employee educational program, performance-based reward system, etc. The successful firms also aggressively pursue diverse external linkages with outside technology sources to learn product and process technologies. Fiendly, this study discusses several implications of the findings for the theoretical development and strategic management of small firms in Korea.

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