• Korean Journal of Plant Tissue Culture
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• v.21 no.1
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• pp.15-22
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• 1994

To understand the molecular mechanism of hardening process in somatic embryo development and artificial seed germination in celery (Apium graveolens L.), the changes of protein synthesis by ABA or cold teatment at early globular stage were examined. Protein content and nitrate reductase activity in ABA- or cold-treated somatic embryo and seedlings were higher than that in unheated ones. The protein content and nitrate reductase activity were more prominent in somatic embryos than in seedlings. From two-dimensional electrophoresis, several protein spots specific to ABA or cold treatment were identified: 30 KD, 32 KD, 171 KD and 205 KD at heart-shaped stage; and 29 KD, 33 KD, 37 KD, 38 KD, 41 KD, 55 KD, 66 KD, and 110 KD at cotyledonary stage were the most specifically synthesized However the synthesis of certain polypeptides were repressed at heart-shaped or cotyledonary stage: 42 KD, 44 KD, 59 KD, 64 KD, 101 KD, 104 KD, and 190 KD at heart-shaped stage; and 29 KD and 116 KD at cotyledonary stage. The protein pattern changes by ABA or cold treatment occurred simultaneously and mainly in acid-soluble proteins during somatic embryo development and artificial seed germination. Therefore it is suggested that the metabolic changes for adaptation to environmental change occur during somatic embryo development and the germination and growth of seedling from embryo.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.4
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• pp.207-215
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• 2004

Recently, securing a vast land in the land region becomes more difficult and efforts to seek its alternation in the sea area have been increased. As a consequence, the coastal region has been faced to extensive beach erosion problems. In planning offshore structures such as artificial islands, it is necessary to forecast the influence of the structure construction exerting on the beach erosion of the adjacent coast. In the present study, the sediment movement pattern behind offshore structure was examined through a series of three dimensional movable bed experiments, so as to develop the numerical model which forecasts morphological change including beach erosions. The experimental results reveal that the sediment movement patterns of the beach line side and the depth region are separated at a certain boundary line. In details, at the beach side including swash zone the sediment movement becomes dominant, which is governed by a relation between depth contours and incident wave directions, while at the depth region the bed load and suspended load due to the orbit motion of waves are carried by nearshore currents, and both movements are clearly separated at a specified boundary that is related to partial standing wave from the beach. It is expected that these results can be effectively used for verification of a numerical model on morphological change of the coast.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.117-125
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• 1992

Dogs were divided into 3 groups of two each; Bacillie Calmette-Guerin(BCG) pretreatment, M bovis only treatment and uninfected control group. BCG were vaccinated intradermally with 0.2ml before 3weeks of M bovis intraperitoneal infection. Infection at necropsy 4months later was readily in the both treated dogs. Histopathologically, the BCG pretreated dogs produce the moderate accumulation of macrophages and focal granuloma formation in the lung, whereas the M bovis only treared dogs produce the accumulation of predominantly macrophages, occasionaly polymorphonuclear cells and the more larger granuloma Bronchoalveolar lavage(BAL) was obtained and total and differential cell counts were examined. Total number of BAL cells harvested from uninfected dogs is lower compared with those of the both treated groups. The total cell number of M bovis only treated dogs were singificantly higher 1.8 times than that of the BCG pretreated dogs. The Fe receptor activity and the growth of organism in alveolar macrophages obtained from BCG pretreated dogs were compared with that in macrophages from M bovis only treated dogs. BCG vaccination resulted in substantial macrophage activation, measured as increased Fc receptor mediated phagocytosis and rosette formation, as wells as the inhibition of intracellular mycobacteria multiplication. However, actibated macrophages taken from BCG pretreated dogs are incapable of killing the M bovis. Thus, these results suggest that BCG pretrearment in the dog may produce a protective effect against tuberculosis because active alveolar macrophages have acquired antituberculous immunity, although few mycobacteria within the lung remain in a metabolically active state.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.2
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• pp.73-80
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• 2007

The chum salmon enhancement program in Korea started at Gowon in Hamgyeong nam-do in 1913 and the program has been more active since Yeongdong Inland Fisheries Research Institute was established at Yangyang in 1984. The major activities were the release of chum salmon fingerlings and the catch of adult chum salmon for artificial fertilization. The range of return rate to Korean waters was in $0.72{\sim}1.57%$ during 1990s, but it has declined seriously since 2000. To overcome the low return rate and enhance chum salmon resources in Korean waters, we must understand the mechanisms of mass mortality of chum salmon during their early life in rivers and coastal areas in conjuction with the fluctuation of return rates and climate. In addition, comprehensive and effective habitat protection and restoration policies will be needed.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.237-246
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• 2002

Tamjin Dam is built in the upper reaches of the Tamjin River which flows through the Janghung-gun and Gangjin-gun of the Jeollanamdo, Korea. In order to map out a preservation strategy of the fish community from dam construction, We studied the distribution of fish distribution and changes of the habitat environment. we found 49 fish species inhabiting in the downstream and upstream of the Tamjin Dam. Among them, migratory fish were two species sweet smelt, Plecoglossus altivelis and freshwater eel, Anguilla japonica. The Coreoperca kawamebari which designated as a species to be protected by The Ministry of Environment of Korea was also observed. After the dam construction, reservoir would be filled with water and running water system will change to standing water system. Then the habitat and spawning space for mountain torrent fish will be reduced and the migration of migratory fish to upstream will be blocked. Through our study, we proposed several ways to protect fish community. In order to preserve the reduced habitat and spawning area of mountain torrent fish, a fishway has been diagnosed to be built in the shallow reservoir in the entrance of the upriver. The establishment of artificial spawning ground on the riverside has been recommended. In addition, We propose a creation of a shelter for fresh water eel, Anguilla japonica in areas where the depth of the water is about l0m by laying rocks. Since it is difficult for a spawning ground to be formed naturally in the reservoir due to the year-round changes in water level, We suggested a floating spawning facility using an artificial fixture. In the downstream of the dam, a waterway-style habitat and spawning ground in the river and increasing the diversity and abundance of fish fauna in the Tamjin River. A low-cost and highly efficient operational fishway has been recommended so that migratory fish such as Plecoglossus altivelis (sweetfish) can migrate from the lower reaches to the upper reaches of the river.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.2
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• pp.112-120
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• 2007

This paper reviews the use of parasites as 'biological tags' for studying stock analysis of salmonid fishes. Numerous definitions of stock concepts exist, but most of them essentially define a group of fish as having similar biological characteristics and being self-reproducing as stocks. It is important to manage fish stocks for human consumption and sustainable production and especially for salmonid fishes. Because these fry are considered as each country's property, it is necessary to identify and discriminate each fish stock in the open sea. Methods of separating fish stocks are very diverse. Artificial tags, parasites, otoliths scales and genetic characters have been used for stock analysis and each method has advantages and disadvantages. Of these parasites can be good biological tags because they are applied by nature at no cost. Parasites can be infected with susceptible host fishes when they enter into certain areas. Then if they move to the outside and are caught researchers can infer that the fish had been in the endemic area for a period of time during their life. Hence the host fish can be considered as naturally 'tagged' by parasites. However, if they do not pass the parasites-endemic. area, they will harbour no parasites. Therefore, researchers can discriminate each fish stocks and trace their migration routes with these biological tags. In this paper, several examples on the use of parasites as biological tags for studying salmonids, as well as other species, are listed. The advantages and limitations of parasites as biological tags are also discussed. Chum salmon (Oncorhynchus keta), the main salmonid species migrating to Korea, is distributed all around the North Pacific. Korean chum salmon are generally thought to move to the Sea of Okhotsk, the western North Pacific and the Bering Sea. However, there is no clear information on the distribution and migration pathways of Korean chum salmon, and no markers exist for separating them from others yet. Recent Korean chum salmon stock analysis including parasites information are mentioned.