• 한국환경과학회지
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• 제25권1호
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• pp.135-146
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• 2016

This study analyzed fluctuations of ground water level of ground water wells developed in Seongsan watershed of Jeju Island until 2013 using MODFLOW, a numerical analysis model. Ground water level shows greater fluctuations from increase of pump capacity compared to the number of ground water wells. The development of ground water at the top of watershed was found to have direct influence on ground water level. Ground water wells developed until 2013 were used to continue pumping for 50 days, and ground water level of coastal region was reduced below 50% compared to the standard water level. In addition, the range of fluctuation of water level was large in the east coast region, which represents the direction of flow of ground water.

• 한국콘텐츠학회논문지
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• 제15권6호
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• pp.539-546
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• 2015

본 연구에서는 수심이 해안선에서 0이 되며 임의로 변하는 축 대칭 지형의 주변을 통과하는 파를 해석하기 위하여 타원형 완경사 방정식을 이용한 수치모델을 개발하였다. 수치해석을 위해 전체 영역을 세 부분으로 구분하였는데, 안쪽 및 바깥쪽 영역에서는 기존 해석해를 활용하였으며, 가운데 영역에서는 지배방정식에서 유한요소기법을 적용하였다. 영역 1에서의 해석해는 변수분리법 및 Frobenius 급수를 사용하였다. 개발된 수치해는 기존에 존재하는 해석해와 비교하여 타당성을 검증하였으며 다양한 경우에 적용하여 활용성을 검토하였다.

• Animal Systematics, Evolution and Diversity
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• 제29권2호
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• pp.129-135
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• 2013

Two species of crabs, Homola orientalis Henderson, 1888 and Pseudomicippe nipponica (Sakai, 1938), are described and illustrated for the first time in Korea. Homola orientalis was collected at 30 m depth by trap from Busan, and P. nipponica was collected on the intertidal region in Seongsanpo, Jejudo Island. Homola orientalis is the first species of its family in the region. The family Homoldae is characterized by a linea homolica on the carapace and they carry camouflage in the form of sponges or cnidarians with subchelate of the fourth ambulatory legs. The Korean brachyuran fauna now comprises 223 species including the new records from this study.

• Animal Systematics, Evolution and Diversity
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• 제36권4호
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• pp.400-407
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• 2020

An epialtid spider crab, Naxioides robillardi (Miers, 1882), is known as widely distributed in Indo-West Pacific region include Japanese waters. Four specimens of epialtid crabs were collected from adjacent waters of Jejudo Island and identified as N. robillardi. This species can be grouped into two forms such as N. robillardi form typical and N. robillardi form mammillata according to morphological features of carapace, gastric spine, and chela. Morphological characters of all Korean specimens well agree with the form mammillata in general. In this paper, morphological diagnosis and illustrations of newly collected N. robillardi are provided. DNA barcode sequence of COI region is also determined for the first time.

• Animal Systematics, Evolution and Diversity
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• 제39권1호
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• pp.53-57
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• 2023

During a survey for the southern sea of Korea, an iphiculid crab, Pariphiculus coronatus, was newly recorded from Korea. Specimens were obtained at a depth of 109-120 m near Jejudo Island. Pariphiculus coronatus can be distinguished from congeners by the following characters: the carapace length and the carapace width subequal, the surface of carapace covered with round granules, the medial tubercles of the intestinal and cardiac region of the carapace, and the first gonopod curved in the half region and straight in the distal portion. The Korean leucosiods have 16 genera and 20 species so far. Here we provide the diagnosis and illustration of Pariphiculus coronatus.

• Animal Systematics, Evolution and Diversity
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• 제39권4호
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• pp.284-288
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• 2023

In this article, a phyllidiid nudibranch which is distributed widely in the Indo-Pacific region, Phyllidia varicose Lamarck, 1801, is reported based on a specimen collected from Seopseom Islet, Jeju Island, Korea. This species is characterized by bluish-gray dorsal tubercles with a yellow cap and three distinct ridges consisting of dorsal tubercles going from the anterior to posterior region, the presence of bluish-black pigment between the dorsal ridges, and a characteristic black longitudinal stripe along the midline of the sole. In this study, we provide a key to species belonging to the genus Phyllidia discovered in Korea, the morphological descriptions, photographs, and a sequence of partial mitochondrial cytochrome c oxidase subunit I of P. varicosa. Currently, four species of the genus Phyllidia have been reported to be present in Korea, including P. varicosa.

• Journal of Species Research
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• 제13권3호
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• pp.306-309
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• 2024

Rhyssemus Mulsant, 1842, represents one of the largest genera in the tribe Psammodiini, comprising approximately 170 species to date. This group is nearly cosmopolitan, excluding the Neotropical region, with 59 species recorded in the Palearctic region. On the Korean Peninsula, only one species, Rhyssemus koreanus Stebnicka, 1980 was recorded from North Korea. In this study, the genus Rhyssemus is recorded for the first time with a newly recorded species Rhyssemus inscitus (Walker, 1858) from South Korea. Adult specimens were collected from the costal sand dunes in Taean-gun and Jeju island. We herein provide a diagnosis, illustrations of morphological characters, and habitat information. Partial mitochondrial COI sequences of the species are also provided for DNA barcoding.

• Molecules and Cells
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• 제24권3호
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• pp.364-371
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• 2007

The tumor suppressor gene Ras association domain family 1A (RASSF1A) is highly methylated in a wide range of human sporadic tumors. The current study investigated the hypermethylation of RASSF1A, the expression of RASSF1A protein, and the correlation between these and the clinicopathological features of gallbladder (GB) cancer in Korean patients. Formalin-fixed, paraffin-embedded tumors and non-neoplastic GB tissues (22 carcinomas, 8 adenomas, 26 normal epithelia) were collected from patients who had undergone surgical resection. The methylation status of two regions of the RASSF1A CpG island was determined by methylation-specific PCR (MSP), and the expression of RASSF1A protein was examined by immunohistochemistry using tissue microarrays. The K-RAS mutation was analyzed by direct sequencing. Methylation of the RASSF1A promoter (region 1) was detected in 22.7% (5/22) of carcinomas, 12.5% (1/8) of adenomas, and 0% (0/26) of normal gallbladder epithelia (P = 0.025). Methylation of the first exon (region 2) was found in 36.4% (8/22) of carcinomas, 25.0% (2/8) of adenomas, and 8.0% (2/26) of normal gallbladder epithelia (P = 0.038). K-RAS mutations were present in 4.5% (1/22) of carcinomas and 25% (2/8) of adenomas. RASSF1A methylaton was not associated with clinicopathological factors or K-ras mutation. Reduction or loss of RASSF1A expression was observed in most methylated adenocarcinomas. Three RASSF1A-expressing human biliary tract cancer cell lines examined contained unmethylated promoters and exons 1. These results suggest that downregulation of RASSF1A expression by DNA hypermethylation may be involved in GB carcinogenesis.

• 한국해양학회지:바다
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• 제8권3호
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• pp.317-326
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• 2003

연안수에서 유기 화합물의 정량적인 특성을 파악하기 위하여 인천 연안 지역, 포항의 영일만을 포함한 형산강 지역 그리고 부산 연안 지역에서 시료를 채취하였다. 또한 강화도와 세어도에서 고정관측도 하였다. 연안수의 총유기탄소(TOC)와 염분과의 상관 관계 및 화학적 산소요구량(COD)과 염분과의 상관 관계를 이용하여 추정한 하천에서 연안역으로 유입되는 총유기탄소의 riverine end-member 값은 5.32 mg C/l, 화학적 산소요구량의 riverine end-member 값은 8.87 mg $O_2$/1로 나타났다 고온 촉매 산화(HTCO)방법을 이용하여 측정한 총유기탄소와 화학적 산소요구량을 비교한 결과 화학적 산소요구량은 총유기탄소의 약 47%를 반영하는 것으로 나타났다. 총유기탄소와 화학적 산소요구량에 대한 상관 관계식은 COD(mgO$_2$,/1)=0.61$\times$TOC(mg C/l)-0.03,($R^2$=0.66)으로 이 관계식을 이용하면 기존에 보고된 화학적 산소요구량으로 총유기탄소를 추정하는데 활용할 수 있을 것으로 판단된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제25권2호
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• pp.209-213
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• 2012

The propolis was collected from the whole part of Korea Peninsula, such as central, southern, and Jeju island, to analyze the general composition including total flavonoid and phenolic contents, heavy metals, colors, amino acids, and crude lipid. The total flavonoid and phenolic contents of middle region in Korea Peninsula (4.26% and 13.06 g/100 g gallic acid) were higher than southern region (2.53%, 10.9 g/100 g gallic acid) and Jeju island (0.03%, 7.22g/100 g gallic acid), respectively. The heavy metals contents showed that Zn contents were found in $0.44{\pm}0.2ppm$ and a harmful heavy metal such as Cr, Cd, Pb, Ni, Cu, As, and Hg were not detected at all in our experiment. The colors of extracted propolis showed a various spectrum from yellow to red purple. Various amino acids were also detected as proline, valine, methionine and the average crude lipid contents of propolis were 42.4%. All data collected in South Korea were very first executed in our institution for the purposes of utilizing and developing the industrial insects, honeybees as well as silkworm.