• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.232-233
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• 2002

In recent years devastation on coasts worldwide has led to barren grounds resulting in the loss of the natural population of many marine organisms and macrophytes. Furthermore, fishery resources such as abalone, fish and seaweeds have been depleted (Serisawa and Ohno, 1995). Since 1980, many fishery scientists and phycologists have tried to create artificial seaweed beds using various technique in order to recover lost seaweed beds (Ohno, 1993; Choi et al., 2000). (omitted)

• Journal of Microbiology
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• v.40 no.4
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• pp.295-300
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• 2002

Previously, we reported induced expression of developmentally regulated CTP-binding protein 2 (DRG2) in fish cells at the late stage of rhabdovirus infection. To investigate the biological role of fish DRG2 (fDRG2), we transfected CHSE-214 cells with an expression vector containing complete fDRG2 fused to the N-terminal end of an enhanced green fluorescent protein (EGFP). Low level expression of fDRG2-EGFP did not induce morphological change or cell death. However, a high level expression of fDRG2-EGFP induced cell rounding and caused depletion of the cell population in FACS analysis. Several truncated fragments were fused to EGFP. FACS analysis was conducted to determine the presence of cells expressing high levels of the resulting chimera. While cells expressing a high level of N-terminus were detected, those expressing high levels of the C-terminal fragment 243-290 containing the G4 motif were absent in FACS analysis. Based on these observations, we propose that overexpression of fDRG2 may induce cell rounding, a representative cytopathic effect of virus-infected cells in the late stage of infection and the C-terminus of the fDRG2 is essential for this function.

• Journal of Environmental Science International
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• v.22 no.1
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• pp.25-35
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• 2013

The concentration of organic compounds was analyzed at each step of BAC process though $BDOC_{total/rapid/slow}$. Further, bacteria communities and biomass concentrations measured FISH and ATP methods were analyzed. The bed volume (BV) of steady state is different from that of based on assessment of organic compounds removal. Bed volumes in DOC, $BDOC_{rapid}$ and $BDOC_{total/slow}$ removal at steady state were around 27,500 (185.8 day), 15,000 (101.4 day) and 32,000 (216.2 day), respectively. A biomass didn't change after the bed volume reached 22,500 (152.0 day) according to analyzing ATP concentration of bacteria. The concentration of ATP was 2.14 ${\mu}g/g$ in BV 22,500 (152.0 day). The total bacterial number was $4.01{\pm}0.4{\times}10^7$ cells/g at the bed volume 1,150 (7.8 day) (the initial operation) and the number of bacteria was $9.27{\pm}0.2{\times}10^9$ at the bed volume 58,560 395.7 day) that increased more than 200 times. Bacterial uptrend was reduced and bacterial communities were stabilized since BV 18,720 (126.5 day). When BV were 1,150 (7.8 day), 8,916 (60.2 day), 18,720 (126.5 day), 31,005 (209.5 day), 49,632 (335.3 day), 58,560 (395.7 day), a proportion of total bacteria for the Eubacteria were 60.1%, 66.0%, 78.4%, 82.0%, 81.3% respectively. ${\gamma}$-Proteobacteria group was the most population throughout the entire range. The correlation coefficient ($r^2$) between Eubacteria biomass and ATP concentration was 0.9448.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.582-588
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• 2013

The impact of global warming on aquatic systems has been a priority research area in the past decade. However, the possibility that increased temperatures will cause shifts in viral disease outbreaks has not been well addressed. In the present study, with increasing water temperature (WT) in the coastal area of Korea, we estimated the possibility of changes in fish viral diseases. From the present time, WT may rise between 0.62 and $1.7^{\circ}C$ by 2050, and the effect on aquaculture could be more adverse than benefitial. Red seabream iridovirus disease (RSIVD) and viral nervous necrosis (VNN) cause high mortality above 22 and $24^{\circ}C$, respectively, and outbreaks could commence earlier and persist for prolonged periods. Nevertheless, the period of occurrence of viral hemorrhagic septicemia (VHS), which outbreaks at a lower WT (< $18^{\circ}C$), could be shorter than the current infectious period. Thermal stress in fish causes reductions in growth and immunocompetence; thus, increases in summer WT can lead to the development of new viral diseases. WT has a strong influence on fish population dynamics; therefore, entry of new viruses and changes in the prevalence of infection can be expected if carrier fishes are introduced or migrate to Korean waters.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.675-683
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• 2017

Total mercury (T-Hg) and methyl mercury (MeHg) were determined in marine fisheries (41 species, n=87) commonly consumed in Korea, using a gold amalgamation method and gas chromatography-cold vapor atomic fluorescent spectroscopy, respectively. Concentrations of T-Hg and MeHg in all samples (31 fish, 4 crustaceans, 4 cephalopods, and 2 gastropod species) were in the range of 0.016-0.495 (mean, 0.093) mg/kg-wet and not detected-0.338 (mean, 0.067) mg/kg-wet, respectively. The concentrations of MeHg in marine fisheries were significantly correlated with T-Hg concentrations (P<0.001). The highest mean concentrations of T-Hg and MeHg were found in fish species, followed by crustaceans. The contribution of MeHg to T-Hg was in the range of 64-95% (mean, 83%) in cephalopods, 28-98% (mean, 69%) in fish, and 26-88% (mean, 57%) in crustaceans. The weekly intakes of T-Hg and MeHg by fisheries consumption for the Korean general population were estimated to be 0.463 and $0.338{\mu}g/kg$ body weight/week, respectively. The concentrations and intakes of T-Hg and MeHg were less than the allowable residue levels and in the range of 12 to 17% of the provisional tolerable weekly intake (PTWI) applied in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.484-490
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• 1985

Gut contents of larval gunnels collected in Kyonggi Bay, Yellow Sea were examined in order to understand the feeding habit of the fish. There were some differences in the gut contents depending upon the body length of the fish. Most important food organisms were Copepoda followed by Appendicularia, fish eggs and Decapoda larvae. Although major food organisms were closely related to the size of zooplankton population, the fish showed a positive food selectivity for Copepoda with increasing body lengh, while there was a negative selectivity for Chaetognatha regardless of body length. However, there appeared to be no size preference on the food organisms by the larval gunnel.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.251-260
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• 2007

A species composition and population structure of fish, collected 16 times by bottom otter trawl in the coast of Geumo Island, from February 2002 to November 2005, was investigated. The fish species caught by bottom otter trawl from year 2002 to 2005 was entirely 72 species, 41 classes, and 12 orders, and the number of appearance and biomass was 5,999 individuals and 287,902.1g, respectively, being of the Perciformes(31 species and 19 classes; 43.1% in total number of species appeared) as a dominant species. 638 individuals of Leiognathus nuchalis which was 10.6% in total fish were appeared and 465 individuals of Konosirus punctatus(7.8%), 449 individuals of Engraulis japonicus(7.8%). biomass of Sebastes schlegeli was 33,258.7g as a dominant species(11.6% in total fish appeared) and 18,821.1g of Liparis agassizii(6.5%), 16,708.0g of Konosirus punctatus(5.8%). The diversity index of species per months of the collected by a small otter trawl in coastal water of Geumodo from year 2002 to 2005 was 2.860-3.639 and the evenness index was 0.825-0.887 in case of dominance index was 0.224-0.268 against the evenness index. The similarity of community structure per yearly was very high because of the relative difference(0.006), which was the least in 2004 and 2005.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.411-419
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• 2018

This study investigated the survival rates and physiological responses of Korean rockfish, Sebastes schlegeli, in live fish containers ($8^{\circ}C$, 33 psu) for 18 days. The survival rate was 99% and 97% in the control and experimental groups, respectively. Hematocrit and hemoglobin did not differ significantly between the control and experimental groups. Glucose and cortisol rose immediately on the first day of containment, but both gradually normalized. Aspartate aminotransferase and alanine aminotransferase did not differ significantly between the two groups after recovery. $NH_3$ continued to rise after the first day, but decreased to a level not significantly different from that of the control group during the recovery period. Plasma ions and osmolality did not change abnormally. The hemocyte population was not significantly different from that of the control. The ratios of apoptotic and necrotic cells indicated no specific variation in hemocyte viability. The histological changes in the skin and gills were not significantly different from those seen in the control. The experimental data obtained in this study suggest that live fish containers may be used to transport Korean rockfish without significantly affecting their physiology or survival.

• Journal of Environmental Health Sciences
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• v.47 no.1
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• pp.36-44
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• 2021

Objectives: The study aims to examine the variation over roughly the past 10 years (from 2008 to 2018) in the estimated daily dietary Pb intake (Pb-D) based on the variations of daily intake amount and Pb content in respective food groups. The following factors were considered: (1) variation of estimated value of Pb-D, (2) Pb contents in each food group and (3) the most influential food group for dietary Pb intake. Methods: Estimated values of Pb-D were taken from food consumption by the food groups reported in the Korean National Health and Nutrition Survey and the Pb content of each food group as reported in 19 previous publications. Variation from 2008 to 2018 of Pb intake was calculated from daily intake amount and Pb content in each food group. Results: The survey showed that main Pb intake sources were the food groups 'meats and poultry' and 'fish and shellfish'. These food groups showed gradually increased Pb exposure from 2008 to 2018. Estimated daily Pb intake was 42.18 to 57.68 ㎍/day for men and 30.97 to 42.54 ㎍/day for women. Both men and women showed slightly increased dietary Pb intake from 2008 to 2018. The food groups 'meats and poultry' and 'fish and shellfish' proved the highest Pb intake food groups. Estimated Pb intake from 'meats and poultry' was 8.47 to 12.98 ㎍/day and that of 'fish and shellfish' was 5.63 to 10.10 ㎍/day. Conclusion: Over the past ten years, daily Pb intake has slightly increased in men and women. The food groups 'meats and poultry' and 'fish and shellfish' might be the main variation factors of Pb intake.

• Parasites, Hosts and Diseases
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• v.58 no.6
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• pp.647-652
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• 2020

Clonorchis sinensis is the most common fish-borne intestinal parasite in Korea. The aim of the present investigation was to survey the status of C. sinensis infection and analyze associated risk factors in residents of Haman-gun, Gyeongsangnam-do. A total of 5,114 residents from 10 administrative towns/villages voluntarily agreed to participate in the study, which comprised fecal examination, a questionnaire survey for risk factors, ultrasonography, and enzyme-linked immunosorbent assay for cancer biomarker detection in the blood. We detected C. sinensis eggs in 5.3% of the subjects. By region, Gunbuk-myeon had the highest number of residents with C. sinensis eggs. The infection rate and intensity were higher in male than in female residents. Based on the risk factor questionnaire, infection was highly associated with drinking, a history of C. sinensis infection, and the practice of eating of raw freshwater fish. Extension of the bile duct, infection intensity, and cancer biomarker detection significantly correlated with the presence of eggs in the study population. In conclusion, the development of feasible, long-term control policies and strategies for the elimination of C. sinensis in Korea is still required.