• 한국패류학회지
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• 제26권3호
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• pp.227-234
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• 2010

A comparative analysis of size and age structures of coastal subfossil shell assemblages of the shortnecked clam Ruditapes philippinarum from open and protected bays of Cheju Island (Korea) was carried out. On the whole, taking into account the damage of small fragile shells, size and age structures of the shell assemblages corresponded to the classical curve of bivalve population distribution when its mortality diminishes with age increase up to a certain threshold. It was found that shell samples from open bays of the western, southern and eastern coasts included shells of smaller and younger individuals (L ${\leq}$ 40 mm, ${\leq}$ 4 years) than samples from the eastern protected bay (L ${\leq}$ 54.5 mm, ${\leq}$ 6 years). Evidently, strong wave activity was the reason for a short life-span of the clams from the open areas. Growth was investigated retrospectively by annual growth rings on the shells. Growth rates of the clams from the various coasts of Cheju Island differed. However, growth rates of the clams from different biotopes at the same (eastern) side of the Island were similar. Shell height/length and width/length ratios statistically significantly increased with the clam age increase. Most likely, the reason for such shell shape alteration is that more conglobated individuals more survive being more energy-optimal than oblong specimens.

• Fisheries and Aquatic Sciences
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• 제26권5호
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• pp.336-343
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• 2023

This study aimed to know the response of deep-sea squid Sthenoteuthis oualaniensis to the light colors of the artificial bait. This experiment used the commercial artificial flashlight baits commonly sold in the fishing shop. The bait has several different light color combinations. The light colors were modified into several light colors by inactivating certain colors and used as treatments. The study is expected to be able to find flashlight bait's most effective color for squid fishing. We applied red-green, green, blue, and commercial bait lights in this study. Each treatment has 3 replications. The effect was expressed as the amount of squid caught. Data were analyzed by one-way analysis of variance. Results showed a significant effect on the number of squid catches. There was significantly different squid catches among the treatments. It indicates that this artificial flashlight bait could be developed to maximize squid catches. This finding can be used for the local fishermen's income and the squid fisheries development.

• Journal of Microbiology and Biotechnology
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• 제8권5호
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• pp.455-460
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• 1998

In the course of screening for new antitumor substances, a novel cytotoxic agent inducing apoptotic cell death was isolated from the culture broth of marine bacterial strain SCRC A-20. Strain SCRC A-20 was separated from a mollusk and was chemotaxonomically identified as a Streptomyces sp. The cytotoxic substance was purified by organic solvent extraction followed by silica gel column chromatography and preparative TLC. HRFAB-MS determined its molecular formula to be $C_{30}H_{40}N_2O_5$ (MW 508). The 1D and 2D NMR spectral data demonstrated that the substance has a novel lactam structure of a 20-membered macrocycle coupled with a unique acyl tetramine and bicyclo［3.3.0］ octane, which includes three methyl groups, six olefinic protons, five carbonyl groups, a conjugated diene and a dienone. The substance, named aburatubolactam C, appeared to be cytotoxic for various continuously proliferating tumor cells of human and murine origins. The $IC_{50}$ values determined by MIT assay were in the range of 0.3 to $5.8\mug/ml$. When Jurkat T cells were treated with $3\mug/ml$. of aburatubolactam C, the apoptotic DNA fragmentation was detectable within 3 h, indicating that the cytotoxic effect of aburatubolactam C on tumor cells is attributable to the induced apoptosis.

• Journal of the korean society of oceanography
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• 제32권1호
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• pp.28-37
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• 1997

Two marine bivalve shells were collected from the eastern and western coastal regions of Korea, respectively. Stable oxygen and carbon isotope profiles are constructed using the incremental sampling along the axis of maximum growth to provide the continuous ${\delta}^{18}$O and ${\delta}^{13}$C records, which register the physical, biological and chemical properties of seawater where the organisms live. Cycles in the ${\delta}^{18}$O profiles are interpreted as annual along with the identification of annual growth bands; the maximum ${\delta}^{18}$O values correspond with the coldest temperature of seawater whereas the minimum ${\delta}^{18}$O values with the warmest temperature. The primary control on the amplitude of the ${\delta}^{18}$O profiles is seasonal variation of seawater temperature. The offset of the baseline between ${\delta}^{18}$O values of the two specimens is attributed to differences in both temperature and seawater ${\delta}^{18}$O values between two localities. The ${\delta}^{13}$C profiles show the similar seasonality of carbon cycling associated with phytoplankton productivity. The offset in the ${\delta}^{13}$C profiles between two specimens may be, as in the case of oxygen isotope profile, attributed to the different ${\delta}^{13}$C value of the seawater DIC (dissolved inorganic carbon) between the western coast and the eastern coast. Relationships between the shell isotopic composition and the coastal water properties of shell growth are readily interpreted from the ${\delta}^{18}$O-${\delta}^{13}$C pair diagram of the shell isotope data, similar to the use of salinity-${\delta}^{18}$O diagram for identifying water masses. The preliminary stable isotope results of this study suggest that mollusk shell isotope geochemistry may be useful to monitor the properties of water masses in the coastal and inner shelf setting around Korea and improve the interpretation of paleoceanography, provided the fossil mollusks are well preserved.

• 한국해양학회지:바다
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• 제5권4호
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• pp.346-356
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• 2000

본 연구는 강릉 연안역의 사질퇴적상에 서식하는 저서동물군집의 분포양상을 보기 위해 1993년 4월부터 1994년 2월까지 계절별로 조사하였다. 전체 출현종수는 봄철에 109종으로 가장 많았고, 겨울철에 70종으로 가장 적었다. 다모류가 종수와 개체수에 있어서 가장 우점한 동물군이었고, 생물량에 있어서는 연체동물이 가장 우점한 동물군이었다. 전체 대형저서동물의 서식밀도는 여름철에 1,995개체/m$^2$로 최대치를 보였고,가을철에 631개체/m$^2$로서 최소치를 보였다. 조사해역의 주요 우점종은 전 계절에 걸쳐 점하였던 다모류의 Spiophanes bombyx를 포함하여 Prionospio sp., 연체동물의 Alvenius ojianus, 갑각류의 Wecomedon sp.와 Urothoidae spp.였다. 집괴분석 결과 조사해역의 저서동물은 크게 수심이 얕은 연안역과 수심이 깊은 외해역으로 구분되어져 수심에 의해 군집조성이 달라짐을 보였다. 그러나 가을철과 겨울철의 경우에는 남대천과 군성강 등 소규모 하천 주변해역에서는 외곽의 해역과는 군집조성이 차이를 보였다.

• 수산해양기술연구
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• 제45권1호
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• pp.1-13
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• 2009

Experimental fishing operation by the shrimp beam trawl was carried out to investigate the bycatch in order to develop the selective fishing gear of the shrimp beam trawl fishery. The experimental trawling was performed by the prototype fishing gear in coast sea of Boryeong, Buan, Kangjin, Tongyeong and Geoje from 30 April to 13 November 2005. Bycatches of the experimental trawling were analyzed species composition, total length composition. The results obtained can be summarized as follows; Target fishes caught by the shrimp beam trawl were Palaemon gravieri, Crangon Hakodatei, Trachysalambria curvirostris, Parapenaeopsis tenellus, Rhynchocinetes uritai and Matapenaeus joyneri. And their fishing rate and total length range were 50.0%, 46.0%, 2.6%, 0.4%, 0.3%, 0.3% and 40-80mm, 40-80mm, 120-150mm, 60-80mm, 60-80mm, 60-120mm respectively. Bycatches caught by the shrimp beam trawl consisted of fishes of 30 kinds, 6 kinds of mollusk, 5 kinds of shellfishes and 3 kinds of crabs. The main fish was Engraulis japonicus, Platycephalus indicus, Paralichthys olivaceus, Leiognathus nuchalis and Conger myriaster, their occupied rate were 47.0%, 16.6%, 13.6%, 5.5%, 2.7% respectively, and their total length range were 60-150mm, 80-410mm, 80-600mm, 30-80mm and 150-460mm respectively. A number bycatch rates of shrimp beam trawl fishery were 99.7% in Buan, 60.0% in Kangjin, 14.6% in Boryeong, 10.6% in Tongyeong and 2.7% in Geoje, The weight bycatch rate were 99.9% in Buan, 75.1% in Kangjin, 57.1% in Tongyeong, 47.4% in Boryeong and 15.4% in Geoje.

• 한국패류학회지
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• 제27권4호
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• pp.395-400
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• 2011

Phylogenetic analyses on the Phylum Mollusks has so far been conducted by many researchers in the world. However, there was no report on taxonomic analysis on Acila divaricata vigila which is belonging to Class Bivalvia, Subclass Protobranchia. In this study, we performed molecular phylogenetic analysis on Acila divaricata vigila using 16S rRNA sequence through maximum likelihood method. As a result, it is clearly divided into the legion of mollusk classification unit (when you zoom in order) and represented to support the current classification in the Phylum Mollusca belong to Class Bivalvia, Subclass Protobranchia, Subclass Pteriomorphia, Subclass Paleoheterodonta, Subclass Heterodonta and Subclass Anomalodesmacea. To our knowledge, this is the first report of molecular phylogenetic analysis on Acila divaricata vigila using 16S rRNA gene and these data suggests that 16S rRNA gene will be useful for analyzing the phylogenetic relationship of Subclass Protobranchia.

• 한국패류학회지
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• 제26권1호
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• pp.19-31
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• 2010

Seogundo is a small island adjacent to the southern coast of Jeju Island and connected to it by a boulder beach at low tide Surveys of this area were conducted from 2001 to 2009 to enumerate the mollusks there and also to examine their diversity, relative abundance, and ecological relationships. Both the boulder beach itself and several large tide pools were studied, including the coarse sand substrate and several species of seaweed and coralline algae found in the tide pools. Of the 121 species obtained or observed, there were 97 gastropods, 16 bivalves, and 8 polyplacophorans. Live specimens were obtained for about half of those species. About one third were found on rocky substrate, with the most common species being Nodilittorina radiata and Nerita japonica in the upper intertidal zone, N. radiata and Littorina brevicula in the middle intertidal, and Turbo (Lunella) coronata coreensis and Acanthopleura japonica in the lower intertidal and shallow subtidal. The seaweeds and coralline algae contained about 40% of all mollusk species. The most common mollusks in two species of brown seaweed were Ittibittum parcum, Musculus nanus, and Euplica scripta. In a species of red seaweed, Komaitrochus pulcher was the most frequent, as in the coralline algae, along with M. nanus. The coarse sand in the tidepools contained about 25% of the species, with the Cerithiidae having the largest number. A sample of beach drift contained 17 species, with Bittium aleutaceum and Rissoina (Phosinella) pura being most common. Most species, about 60%, were found in a variety of habitats, especially the marine flora; few species exhibited any habitat preferences. Biographically, Jeju Island is part of the Warm Temperate Northwest Pacific Province and the East China Sea ecoregion with a strong faunal affinity with southern Japan, eastern China, and northeastern Taiwan. Zonal-geographical groupings reveal that the fauna is mainly subtropical-low boreal, preferring moderately warm water, with a somewhat smaller number of tropical-subtropical species.

• 한국해양학회지:바다
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• 제10권2호
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• pp.124-128
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• 2005

한국 주변해역의 해양시료에서 측정된 탄소동위원소 연대 값을 실제 역년(calendar age)값에 가깝게 변환하기 위하여 국립수산과학원(NFRDI)에서 제공한 핵실험 이전인 1942년에 한국 연안에서 채취한 2종의 연체동물 패각 시료를 이용하여 marine reservoir correction$({\Delta}R)$ 값을 측정하였다. 남서해안에서의 측정된 ${\Delta}R$ 값은 $-117\pm45\;^{14}C\;yr$, 남동해안에서 측정된 값은 $-160\pm35\;^{14}C\;yr$로 계산되었다. 이 값들은 황해의 중국연안에서 측정된 값들의 범위에 속하는데 이는 중국과 한국 연안해역에서 reservoir $^{14}C$ age가 지구규모의 해양 평균 reservoir $^{14}C$ age보다 적은 값을 갖고 있음을 말한다. 이들 지역의 낮은 ${\Delta}R$ 값은 아마도 담수유입의 영향을 반영하는 것으로 생각된다. 본 연구에서 제시된 ${\Delta}R$값은 한국 주변해역에서 측정된 탄소동위원소 연대 값을 실제 역년 값에 가깝게 변환시킬 수 있도록 도움을 줄 것이다.

• 한국식품영양학회지
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• 제26권2호
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• pp.155-162
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• 2013

The purpose of this study was to compare the preferences for seafood in school lunch menus among elementary school students in Gyeonggi-do. A survey was carried out on 303 male/female elementary school students. As for the preferences for seafood in school lunch menus, 'like (47.2%)', 'fair (30.7%)', and 'dislike (22.1%)' were observed in that order (p<0.01). Concerning the appropriateness of seafood serving frequency, '1~2/week (44.9%)', '3~4/week (33.7%)', and 'everyday (10.2%)' were observed in that order. When the preference of favorite seafood was evaluated using a Likert scale (strongly like 5-points, strongly dislike 1-point), 'crustacea (4.34)', 'mollusk (4.21)', and 'processed food (4.11)' were observed in that order. In terms of cooking methods for seafood, 5th grade students showed higher frequency of 'grilling' and 'frying' seafood compared to others (p<0.05). As for the occurrence of seafood leftovers, 4th and 6th grade students showed higher frequency of 'sometimes' than 5th grade students (p<0.001). As for certain desires for seafood in school lunch menus, 'improvement of taste (39.3%)', 'various kinds of seafood (20.1%)', and 'variable cooking methods (18.5%)' were observed in that order. Therefore, in order to increase the intake of seafood, students should attempt to achieve proper intake though nutrition education.