• Parasites, Hosts and Diseases
• /
• 제45권3호
• /
• pp.199-204
• /
• 2007

Metacercariae of Gynaecotyla squatarolae (Digenea: Microphallidae) were discovered from the shore crab, Macrophthalmus dilatatus, purchased at a market in a coastal town of Taean-Eup, Chungcheongnam-do, Republic of Korea. Their adult flukes were confirmed by experimental infection of rats. The metacercariae of G. squatarolae were elliptical ($391.1{\times}362.5{\mu}m$), and the excysted metacercariae had progenetic genital organs, including the ovary and testes. To obtain adult flukes, 6 Sprague-Dawley rats were fed 500 metacercariae each, and killed at days 2, 4, and 6 post-infection. The adult flukes were identified as G. squatarolae (Yamaguti, 1934) Yamaguti, 1939, based on morphological characters, including 2 ventral suckers (1 large and 1 small), a large genital atrium equipped with the cirrus and the metraterm, separated male and female genital pores, a transversely long cirrus pouch, and extensive vitelline follicles. In the present study, it has been first proven that the shore crab M. dilatatus is a second intermediate host for G. squatarolae in the Republic of Korea.

• Parasites, Hosts and Diseases
• /
• 제48권4호
• /
• pp.335-338
• /
• 2010

Maritrema spp. (Digenea: Microphallidae) are parasites of birds, but have not been found in the Republic of Korea. In this study, metacercariae of Maritrema sp. were discovered in the Asian shore crab, Hemigrapsus sanguineus, caught in the mud-flats of Jebu-do, Hwasung-gun, Gyeonggi-do, and the adult flukes were confirmed by experimental infection into mice. Based on the symmetric ribbon-like vitellarium, adult flukes of Maritrema sp. were identified, but did not belong to previously described species in terms of the following morphologic characteristics: ceca reaching to the lateral wall at the anterior border of the ovary; ventral sucker larger than oral sucker; a prominent metraterm; and vitellarium forming a complete ring. Hence, we named this microphallid M. jebuensis n. sp. after the island where the second intermediate hosts were collected. From this study, it has been shown that Maritrema sp. is distributed in Korea and transmitted by the Asian shore crab, H. sanguineus.

• Animal cells and systems
• /
• 제15권3호
• /
• pp.243-249
• /
• 2011

The genetic diversity and population history of the Asian shore crab, Hemigrapsus sanguineus, were investigated with a nucleotide sequence analysis of 536 base pairs (bp) of the mitochondrial cytochrome c oxidase subunit I gene (COI) in 111 samples collected from four populations in Korea and one in Japan. In total, 28 haplotypes were defined by 27 variable nucleotide sites in the COI region examined. The observed haplotypes had a shallow haplotype genealogy and no geographical associations. Most of the populations had high haplotype diversity (0.656-0.788) and low nucleotide diversity (0.00165-0.00244), and significant negative values for Fu's $F_S$, suggesting rapid and recent population growth from an ancestral population and sudden population expansion. The pairwise fixation indices ($F_{ST}$) estimated with the exact test and the migration rates indicate that substantial gene flow occurs among these populations as a result of sea currents, except between the Yellow Sea coast of Korea (BUA) and the Pacific Ocean coast of Japan (JPA). These two populations (BUA and JPA) showed significant genetic differentiation and low migration rate.

• 한국동물학회지
• /
• 제34권3호
• /
• pp.289-299
• /
• 1991

Two new species of the genus Hemicyclops, H. 형omsoensis n. sp. and H. soxatilis n. sp., taken from crab burrows on each of mud flat and rocky shore, are described from the Yellow Sea coast of southwest Korea.

• 한국수산과학회지
• /
• 제35권2호
• /
• pp.122-129
• /
• 2002

민꽃게를 시료로 하여 바람직한 갑각류 향기성분의 전구물질부가 되는 character impact compounds의 검색 및 게 자숙향기의 발현에 대하여 검토하였다. Methanol이 냄새성분의 전구물질 추출에 가장 적합한 것으로 나타났고, 추출횟수는 3회 정도로 완전추출이 가능했으며, 이때 methanol의 농도는 $80\%$일 때가 냄새의 강도가 가장 강한 것으로 나타났다. 시료 게의 냄새성분의 전구물질부를 구명하기 위해 투석 및 이온 교환수지 방법 등을 이용해 냄새성분 전구물질부를 분획하고 관능검사한 결과, 게 자숙취의 전구물질은 수용성이고 투석성의 저분자 성분으로, 산성 및 양성성분의 물질을 주체로 하여 여러 가지 성분이 동시에 가열될 때 발생하는 것이라고 생각되었다 게육 특유의 자숙취를 발현시킬 목적으로, 민꽃게 육의 $80\%$ methanol 추출성분의 조성에 근거한 합성 게육 엑스분의 조제하여 100$^{\circ}C$C에서 30분간 열처리하여 발생하는 냄새를 천연 게육의 자숙취와 비교하여 볼 때, 냄새의 조화성 면에서는 다소 떨어지나 양시료 사이에는 거의 차이가 없었다. 한편, 천연 및 합성 게육의 자숙취를 GC로 분석하여 chromatogram의 pattern을 비교한 결과 저·중비점 물질의 경우 양자가 서로 유사한 것으로 나타났다. 게 자숙취의 발현에는 염기성아미노산을 비롯한 아미노산류의 역할이 컸으며, ribose와 염기성아미노산 간에 일어나는 Maillard 반응에 의해 생성되는 휘발성화합물, 그리고 4급 암모니움염기가 민꽃게 자숙취의 주요 요소가 될 것으로 추정되었다.

• Biomaterials and Biomechanics in Bioengineering
• /
• 제2권4호
• /
• pp.249-269
• /
• 2015

A problem faced by oil companies is the maintenance of the location register of pipelines that cross the surf zone, the regular survey of their location, and also their inspection. A survey of the state of art did not allow identifying operating systems capable of executing such tasks. Commercial technologies available on the market also do not address this problem and/or do not satisfy the presented requirements. A possible solution is to use robotic systems which have the ability to walk on the shore and in the surf zone, subject to existing currents and ripples, and being able to withstand these ambient conditions. In this sense, the authors propose the development of a spider crab biologically inspired robot to achieve those tasks. Based on these ideas, this work presents a biomechanical study of the spider crab, its modeling and simulation using the SimMechanics toolbox of Matlab/Simulink, which is the first phase of this more vast project. Results show a robot model that is moving in an "animal like" manner, the locomotion, the algorithm presented in this paper allows the crab to walk sideways, in the desired direction.

• Fisheries and Aquatic Sciences
• /
• 제15권1호
• /
• pp.49-56
• /
• 2012

Genetic variation in the Asian shore crab Hemigrapsus sanguineus was determined from partial mitochondrial DNA (mtDNA) sequences of the cytochrome b (Cytb) gene. Samples included 143 crabs from six localities along three coastlines in South Korea. A nucleotide sequence analysis revealed 38 variable sites in a 470-bp sequence, which defined 37 haplotypes. The haplotypes were not associated geographically and had a shallow genealogy. Pairwise $F_{ST}$ tests and a two-dimensional scaling analysis revealed no significant genetic differentiation among most of the populations. The low pairwise comparison values, but significant genetic differentiation of a northeastern population from all other populations, might have been influenced by a restriction in gene flow caused by hydrographic conditions such as ocean boundaries. The high haplotype diversity, low nucleotide diversity, and time since H. sanguineus expansion in Korean coastal waters indicate rapid population growth and a recent, sudden expansion in the Late Pleistocene.

• 한국식품영양과학회지
• /
• 제30권5호
• /
• pp.787-795
• /
• 2001

인간의 기호에 바람직한 풍미를 지니고 있는 갑각류의 풍미발현성분을 살펴보기 위해 민꽃게와 꽃새우를 시료로 하여 효소가수분해물을 조제하고, 이들의 정미성분 및 자숙취성분을 분석하였다. Body effect로서 맛 및 조직감에 영향을 미치는 것으로 알려져 있는 구성지방산의 조성은 민꽃게와 꽃새우 생시료의 경우 양자가 서로 비슷하여, 모두 16 : 0, 16 : 1n7, 18 : 0, 18 : 1n9, 20 : 5n3및 22 : 6n3 등이 주요 구성지방산이었고, n3계열의 고도불포화지방산의 조성비도 각각 27.75% 및 28.46%로서 서로 비슷하였다. 민꽃게와 꽃새우 효소가 수분해물의 유리아미노산 총량은 각각 5,226.7 mg% 및 8,757.3 mg% 및 8,757.3 mg%이었고, 주요 유리아미노산은 양 시료 모두 taurine, asparagine, glutamic acid, glycine, alanine, isoleucine, leucine, phenylalanine, lysine 및 arginine의 함량이 많았고, dipeptide인 anserine도 비교적 많이 함유되어 있었다. 대부분의 아미노산이 꽃새우 쪽에 많이 함유되어 있었으며, 특히 asparagine, lgutamic acid 및 proline 등은 꽃새우 쪽에 2배 이상 함유되어 있었다. 그리고 수산무척추동물 엑스분의 상쾌한 맛의 주성분인 betaine 함량은 각각 850.0 mg% 및 755.9 mg%로 다량 함유되어 있었다. ATP관련물질 중 AMP의 함량이 약간 많았으나, 양시료 모두 정미발현에 큰 영향을 주지는 못할 정도였다. 무기이온성분으로는 양시료 모두 Na, K, P 및 Cl 이온이 양적으로 많았으며, 그외 Ca 이온도 비교적 많이 함유되어 있었다. 민꽃게 효소가수분해물의 자숙취 성분은 acid류 6종, alcohol류 10종, aldehyde류 7종, ketone류 11종, ester류 1종, phenol류 5종, benzene류 4종, hydrocarbon류 22종, furan류 1종, 함질소화합물 21종 및 기타 11종으로 구성되어 있었고, 계수적인 측면에서 가장 많은 종류의 화합물은 alkane류를 위주로 한 hydrocarbon류 및 pyrazine류 5종, hydrocarbon류 36종, furan류 1종, 함질소화합물 14종 및 기타 8종이 동정되었다.

• Fisheries and Aquatic Sciences
• /
• 제10권2호
• /
• pp.86-92
• /
• 2007

Adult Dungeness crabs are restricted primarily in the lower part of Glacier Bay, Alaska, but the interaction of larval dispersion and adult distribution is unknown. To understand the larval occurrence in the upper part of Glacier Bay, Dungeness crab larvae, sea surface temperature (SST), and sea surface salinity (SSS) were collected at 16 near-shore and 12 mid-channel stations in Glacier Bay, southeastern Alaska during six sampling periods from March through August 2000. Each station was visited from one to five times during the entire sampling period. Geographic Information System (GIS) was used to contour SST and SSS distribution in Glacier Bay. Seven to 27 stations were visited during each sampling period. Most larvae (85% were zoeae I) occurred during May 31 to June 14, 2000. Larval density varied from none to $51.4\;100\;m^{-3}$ between stations. A few later stage larvae occurred during later sampling periods. Overall, no relationship between larval densities, and SSS, and SST existed. Larvae occurring in the upper bay were probably transported by tidal currents from the lower bay; adult Dungeness crabs in Glacier Bay have a relatively high density near the mouth of the bay but decrease sharply around 40km north of the mouth. The lack of adult crabs in the upper 60km of the bay may be related to lower salinity, resulting in sharp haloclines, or colder temperatures which are not conducive to survival or growth of either larvae or adults.

• 수산경영론집
• /
• 제52권2호
• /
• pp.1-31
• /
• 2021

This study is to evaluate the prior economic feasibility of the off-shore fisheries stock enhancement project. The main findings of this study can be summarized as follows: first, offshore fisheries stock enhancement project shall be implemented by dividing them into 1st·2nd·3rd projects for efficient promotion. The 1st·2nd·3rd projects will be conducted in a total of 50 locations (the eastern sea, the western sea, the southern sea, and the jeju sea areas), and the project period per unit will be five years, which will cost 1 trillion won. Second, according to the results of the survey on public awareness, the most consumed marine species in Korea over the past year were analyzed in the order of mackerel, hairtail, squid, yellow corvina, blue crab, and cod. The dominant response to the reason for consuming marine products in Korea was healthy well-being food and safe food. In addition, 67.9% of them have hesitated to purchase offshore fish species over the past year due to high prices, indicating that they are burdened by high prices. On the other hand, 79% of the respondents said that the government's policy was insufficient, according to a survey on whether the government's coastal marine resource creation policy was sufficient. Third, as a result of preliminary economic analysis of offshore fisheries stock enhancement project, the benefit-cost ratio is 4.01, net present price is 1,283.7 billion won, and internal rate of return is 91.7% per year, which means that the economic analysis ensures the feasibility of the projects. The results of this study provide useful information on securing or organizing budgets for offshore fisheries stock enhancement project by securing economic feasibility as a national infrastructure project that increases fishery income and public benefits such as consumption of marine products.