• Parasites, Hosts and Diseases
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• v.25 no.1
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• pp.59-68
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• 1987

An epidemiological survey on Metagonimus yokogawai infection was performed in the eastern coast area of Kangwon province. Formalin-ether concentration technique and Stoll's dilution egg counting method were employed to figure out the prevalence and intensity of M. yokogawai infection and eating habits of inhabitants with raw freshwater fish. The results are summarized as follows: 1. The prevalence rate of M. yokogawai infection was 6.6% among a total of 2, 357 examinees; 8.6% (115 out of 1, 345) in male and 4.0% (40 out of 1, 012) in female. 2. The prevalence rates were different by the streams where the examinees were residing: 17.8% along the area of Ohsip-cheon (stream), 11.8% along Maeup-cheon, 1.7% along Hwasang-cheon, 1.3% along Yeongok-cheon, 0.9% along Namdae-cheon, 0.9% along Sa-cheon and 0% in the other streams (Yongchon-cheon, Kangnung Namdae-cheon and Jusoo.cheon) in decreasing order. 3. By social strata, the positive rate was 8.0% (122 out of 1, 521) in general inhabitants and 3.9% (33 out of 836) in school children. 4. By the intensity of infection by means of EPG counts in feces; the light infection (less than 400/EPG) was 74.1%, moderate infection (401-1, 000/EPG) 17.3% and heavy infection (more than 1, 001/EPG) 8.6%. 5. Twelves out of 50 sweetfish (Plecoglossus altivelis) (24%) caught from the streams in eastern coast of Kangwon-Do were infected with metacercariae of M. yokogawai, and the number of larvae detected were 70.7 per 6sh in average. The metacercarial infection rates in fish were also different by the streams; 100% in Ohsip-cheon of Samcheok-Gun, 14.3% in Sa-cheon, 16.7% in Yeongokcheon of Myeongju-Gun and 0% in Namdae-cheon of Yangyang-Gun, respectively. 6. Six hundred ninety live (695) out of 1, 396 inhabitants and school children (49.8%) were experienced in eating raw freshwater fishes (Plecoglossus altivezis, Triboledon hakonensis, Coreoperca sp., Morose sp., Carassius sp. & Cyprinus sp. and Zacco platypus). The data were assayed with the questionnaire collected from the examinees. In summarizing the above results, it is known that the Ohsip-cheon area of Samcheok-Gun is highly infected region, and the other areas of Kangnung Namdae-cheon, Yeongok-cheon and Yangyang Namdae-cheon are very lowly infected or non-infected regions for M yokogawai infection.

• Journal of the Korean Society for Library and Information Science
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• v.52 no.1
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• pp.65-86
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• 2018

This study was conducted to analyze the characteristics of records related to Korea shown in the cataloging records of national libraries of the main 10 developing countries in Asia and Africa. The results are as follows. To begin with, Korea-related records in most national libraries are very poor and under 0.1% of the library. Except for National Library of Viet Nam, the figure is under 3,000 volumes and generally 2 times less than Japan related records. Second, except for National Library of Iran and Viet Nam most national libraries romanize Korean materials, there are not marked with the original Korean language and unfeasible Hangeul search. Third, on investigation of the subject distribution in sub criteria of Korea-related records, subject related to history and economy is largely shown in the highest rate. Fifth, among the Korea-related subject heading, Taekwondo is marked with distinction from Karate in most libraries except for 7 national libraries. Dokdo is marked with the geographical name of 'Korea' in 7 national libraries and East Sea (Donghae) already is marked with 'Japan, Sea of' in 7 national libraries. Amnokgang, Dumangang, and Baekdusan-related records did not search at all in most national libraries.

• Journal of Life Science
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• v.21 no.2
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• pp.176-182
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• 2011

Deep seawater (DSW) generally refers to seawater at depths equal to or greater than 200 meters. DSW is rich in inorganic materials which have attracted attention for its various applications. In this study we investigated the effects of the DSW upwelled from the East Sea, offshore Yang Yang (KangWon-do, Korea), on the expression of ${\mu}$-opioid receptor (MOR) of cultured rat hippocampal neurons. Neurons were grown in a minimal essential medium containing 10% (v/v) fetal bovine serum and either 25% (v/v) distilled water, or hardness (H) 800, or H 1000 DSW. Cultures grown in the presence of DSW with H 800 and H 1000 exhibited robust MOR immunoreactive signals in both neurons and astrocytes. Interestingly, the increase in MOR immunoreactive signals was more dramatic in astrocytes than in neurons. Statistical analysis revealed that the relative intensities for MOR clusters increased approximately 4-fold in astrocytes cultured in H 800 and H 1000 media. These increases were statistically very significant (p<0.001). In contrast, the increase in intensities for MOR immunoreactive signals was relatively less dramatic in neurons, where only the increase in the H 1000 culture was statistically very significant (p<0.001). These results indicated that DSW promotes expression of MOR in both neurons and astrocytes, and more significantly in the latter.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.187-198
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• 2003

High-resolution (Chirp, 3-11 kHz) echo facies and sedimentary facies of piston-core sediments were analyzed to reveal the late Quaternary depositional processes in the Korea Plateau and Ulleung Interplain Gap. The Korea Plateau is an Isolated topographic high with a very restricted input of terrigenous sediments, and its slope is characterized by a thin sediment cover and various-scale submarine canyons and valleys. Echo and sedimentary facies suggest that the plateau has been moulded mainly by persistent (hemi) pelagic sedimentation and intermittent settling of volcanic ashes. Sediments on the plateau slope and steep margins of ridges and seamounts were reworked by earthquake-induced, large-scale slope failures accompanied by slides, slumps and debris flows. As major fraction of the reworked sediments consists of (hemi) pelagic clay particles, large amounts of sediments released from mass flows were easily suspended to form turbid nepheloid layers rather than bottom-hugging turbidity currents, which flowed further downslope through the submarine canyons and spreaded over the Ulleung Basin plain. In the Ulleung Interplain Gap, sediments were introduced mainly by (hemi) pelagic settling and subordinate episodic mass flows (turbidity currents and debris flows) along the submarine channels from the slopes of the Oki Bank and Dok Island. The sediments in the Ulleung Interplain Channel and its margin were actively eroded and reworked by the deep water flow from the Japan Basin.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.3
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• pp.103-117
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• 2017

This note provides technical guide on three issues associated with establishing and automatically running regional ocean forecasting systems: (1) a strategy for continuous production of hourly-interval three-day ocean forecast data, (2) the daily download of ocean and atmospheric forecasting data (i.e., HYCOM and NOAA/NCEP GFS data), which are provided by outside institutions and used as initial condition, surface forcing, and boundary data for regional ocean models, and (3) error notifications to numerical model managers through the Short Message Service (SMS). Guidance on dealing with these three issues is illustrated via solutions implemented by the Korea Hydrographic and Oceanographic Agency, since in embarking on this project we found that this procedural information was not readily available elsewhere. This technical guide is based on our experiences and lessons learned during the process of establishing and operating regional ocean forecasting systems for the East Sea and the Yellow and East China Seas over the 5 year period of 2012-2016. The fundamental approach and techniques outlined in this guide are of use to anyone wanting to establish an automatic regional and coastal ocean forecasting system.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.256-261
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• 1991

To isolate new antioxidants from twelve edible seaweeds, mixed methanol and chloroform extract of marine algae was fractionated into several subfractions and their antioxidant activities were measured by using AOM and 1, 1-diphenyl-2-picrylhydrazyl (DPPH). Especially the aqueous-methanol soluble fractions of brown and red algae showed a considerable antioxidant effect. Their antioxidant activities were stronger than synthetic antioxidants such as BHA, BHT, under the same concentration. Further fractionation of the aqueous-methanol soluble fractions using silica gel column chromatography yielded five subfractions. Among them methanol fraction exhibited high DPPH quenching activities. Also, it was confirmed to be benzene-derivative substances of two compounds by UV, HPLC, GC/MS analysis. Its each molecular weight was about 181, 238. These results suggested the existence of two effective natural antioxidant compounds in three edible marine algae.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.4
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• pp.238-246
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• 1991

In order to make clear the mechanism forming the fishing ground of anchovy drag net in connection with water temperature, catch and oceanographic data for the years of 1970-1988 in the Southern Sea of Korea were analyzed. The annual catch of anchovy drag net was about 21,000M/T in 1970 but it was increasing largely so far 100,000M/T in recent years. The fishing season of anchovy drag net is the whole year beside the prohibition season established in aims to protect the spawning group of anchovy, and then in the best season of the period from July to December, the fishing ground is made up in the coastal area joining Yosu, Namhaedo and Bangeojin. There were some evidences that the fishing condition was controlled by the oceanographic condition, especially water temperature, that is, when there was large difference in water temperature between the south area of the Eastern Sea and the west area of the southern Sea and the thermocline is formed strongly in the larger less than 20m, the fishing condition was good. On the other hand, there was a very effective correlation between the catch(X) of anchovy spawning group in Spring by other fishing gears, mainly drift net and that(Y) of the little size of anchovy by drag net in Autumn, expressed by the relative equation, Y=62,246+1.3X, r=0.63.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.422-430
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• 2016

We investigated the abundance and composition of the zooplankton community around Dokdo in the East Sea from 2006 to 2015. Zooplankton samples were collected in the surface mixed layer by vertical hauls using a standard type net at the monitoring stations. There were no clear long-term trends in the average temperature and salinity, but relatively low salinity was recorded in the summer of 2013 and 2015. The average abundances of zooplankton in the summer increased by two orders of magnitude from $317inds./m^3$ in 2008 to $10,242inds./m^3$ in 2015. This long-term increase was accompanied by a slight increase in the chlorophyll-a concentration and a decrease in the catch of potential crucial predators (anchovy, mackerel pike, squid, herring and horse mackerel) in the study area. The dominant zooplankton, accounting for most of the long-term increase, consisted of appendicularian (Oikopleura spp.), which showed a steady increase since 2012, summer species such as Noctiluca scintillans and the cladoceran Penilia avirostris, which showed an abrupt increase, and the copepod Paracalanus parvus s.l., which showed a rapid increase after its first occurrence in summer 2010. These results suggest that the long-term increase of zooplankton could be related to the increase in the concentration of prey and the decrease in the predation pressure of potential predators around Dokdo in the study area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.632-640
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• 2017

In order to understand the seasonal and geographical characteristics of environmental factors and distribution of Escherichia coli by salinity gradient due to precipitation, we investigated abiotic and biotic factors during four seasons from February 2013 to November 2015. The study area was divided into three different zones based on salinity gradient and geo-oceanographic characteristics. During the study period, water temperature, salinity, Chlorophyll a, and secchi-depth varied in the range of $8.5-26.1^{\circ}C$, 13.5-34.4 psu, $0.4-74.0{\mu}g\;L^{-1}$, and 0.5-10.0 m, respectively. Salinity was low at Zone I, which was influenced by water flux from Tae-hwa River, especially in 2014. Salinity was gradually increased (one-way ANOVA; p < 0.05) toward Zone III located offshore of the bay. The highest colony form of E. coli was detected at Zone I. E. coli maintained a relatively low level at Zone III during all seasons. E. coli was correlated with transparency (r = -0.36; p < 0.05) and salinity (r = -0.53; p < 0.01), implying that those parameters might play important roles in the proliferation of E. coli. These results indicated that E. coli were strongly affected by frequent rain (< 50 mm) around inner stations in Ulsan Bay of Korea.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.96-102
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• 2011

The objective of study was carried out to find a proper entrance date for breaking dormancy depending on cutting and entrance date into greenhouse investigating plant growth and flowering characteristics of chrysanthemum 'Baekma'. Days to visible bud formation and days to flowering were increased as cutting date was delayed. The flowering rate of cutting on September 18 was 100% while cutting on October 30 did not induce flower bud formation. Flower characteristics were surveyed after 'Baekma' and 'Jinba' rooted cuttings were planted on September 10. Branching formation rate of 'Baekma' was gradually increased as entrance date was delayed while that of 'Jinba' was about 70-80% regardless of entrance date. Lethality of 'Baekma' moving into greenhouse on December 20 was 1.5% by cold injury. 'Jinba' started to die on November 10 by cold injury and lethality of 'Jinba' moving into greenhouse on December 20 was 21.7%. Thus, lethality of 'Jinba' was about 5-14 times higher than that of 'Baekma'. Days to visible bud formation and days to flowering were decreased as entrance date was delayed in chrysanthemum 'Baekma'. Days to visible bud formation of entrance date on November 10 and December 10 were 67.9 and 50.3, respectively. On the other hand, that of 'Jinba' was increased until entrance date on December 10 and decreased on December 20. Based on these results, it was suggested that dormancy of 'Baekma' was started at late September and completed at late October.