• 한국양식학회지
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• 제4권2호
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• pp.129-136
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• 1991

This is a review of the studies on aquaculture and its environments in Jinhae Bay, one of the most productive areas in the south coastal waters in Korea, carried out since 1960's. It's content consists of describing the outlines of, (1) a brief history of shellfish culture development and the study of oceanic environments relating to the aquaculture, (2) the oceanographic studies on the eutrophication, red tides, and the mass mortality of shellfish due to pollution and (3) the studies on forecasting aquaculture and oceanographic conditions, and on the direction of aquacultural oceanographic studies in the near future.

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1139-1142
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• 2009

Refinement of NMR structures by molecular dynamics (MD) simulations with a solvent model has improved the structural quality. In this study, we applied MD refinement with the generalized Born (GB) implicit solvent model to protein structure determined under membrane-like environments. Despite popularity of the GB model, its applications to the refinement of NMR structures of hydrophobic proteins, in which detergents or organic solvents enclose proteins, are limited, and there is little information on the use of another GB parameter for these cases. We carried out MD refinement of crambin NMR structure in dodecylphosphocholine (DPC) micelles (Ahn et al., J. Am. Chem. Soc. 2006, 128, 4398-4404) with GB/Surface area model and two different surface tension coefficients, one for aquatic and the other for hydrophobic conditions. Our data show that, of two structures by MD refinement with GB model, the one refined with the parameter to consider hydrophobic condition had the better qualities in terms of precision and solvent accessibility.

• Mycobiology
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• 제47권3호
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• pp.261-272
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• 2019

Oomycetes are widely distributed in various environments, including desert and polar regions. Depending upon different habits and hosts, they have evolved with both saprophytic and pathogenic nutritional modes. Freshwater ecosystem is one of the most important habitats for members of oomycetes. Most studies on oomycete diversity, however, have been biased mostly towards terrestrial phytopathogenic species, rather than aquatic species, although their roles as saprophytes and parasites are essential for freshwater ecosystems. In this study, we isolated oomycete strains from soil sediment, algae, and decaying plant debris in freshwater streams of Korea. The strains were identified based on cultural and morphological characteristics, as well as molecular phylogenetic analyses of ITS rDNA, cox1, and cox2 mtDNA sequences. As a result, we discovered eight oomycete species previously unknown in Korea, namely Phytopythium chamaehyphon, Phytopythium litorale, Phytopythium vexans, Pythium diclinum, Pythium heterothallicum, Pythium inflatum, Pythium intermedium, and Pythium oopapillum. Diversity and ecology of freshwater oomycetes in Korea are poorly understood. This study could contribute to understand their distribution and ecological function in freshwater ecosystem.

• 생태와환경
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• 제44권2호
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• pp.103-112
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• 2011

내분비계장애물질과 같은 유기화합물에 의한 수계의 오염은 지구적인 양서류 감소의 원인으로 의심되고 있다. 양서류는 수정 후 변태에 이르는 생활사를 수중에서 진행하므로 수환경 오염물질에 의한 독성효과를 연구하기에 적합한 모델이다. 또한 양서류는 인간을 비롯한 육상척추동물과 발생학적으로 많은 공통점을 가지므로 공중보건학적 관점에서도 수환경 오염물질의 위해성 평가에 적항한 모델생물이다. 특정 화학물질이나 환경매체의 안전관리 기준을 설정하고 수환경의 독성물질 관리를 위해서는 다양한 독성종말점에서 독성정보가 필요하다. 알킬페놀류 화합물은 농업, 공업, 가정활동에 사용되고 있으며, 수환경 내에 잔류하여 다양한 수생동물에서 내분비계장애효과를 갖는다. 본 소고에서는 양서류의 배아, 유생을 대상으로 알킬페놀류 화합물의 종류별, 노출경로 및 농도, 노출 시기에 따른 발생장애와 발생기형 유발효과와 그 기작에 관한 국내외 자료를 정리하였다. 육수환경 잔류 오염물질의 중장기 노출독성 평가모델로서 양서류배아 발생독성평가법의 유용성을 제안하였다.

• 한국수산과학회지
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• 제27권3호
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• pp.292-298
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• 1994

식중독 원인균으로 알려진 Vibrio mimicus(V. mimicus)의 분포 상태와 이의 생리적 특성을 조사하기 위하여 1993년 1월부터 9월까지 민락동과 광안리 해수욕장 부근의 해수를 채취하여 V. mimicus의 월별 분포 상태를 실험하였으며, 여기서 분리된 균주 중에서 항생제 내성이 강한 균으로 분리, 동정된 V. mimicus K-1의 생리적 성질과 배양 특성을 조사하였다. 수온이 $16.3^{\circ}C$인 4월부터 검출되기 시작하여 8월까지 검출되었으나, 수온이 $15^{\circ}C$ 이하인 겨울철(1, 2, 3월)에는 전혀 검출이 되지 않았다. 분포 정도는 최소 0.4(MPN/100ml)에서 최고 70((MPN/100ml)으로 지역에 따라 차이가 있었다. V. mimicus K-1은 $37^{\circ}C$, pH 7.5, 그리고 염도 $0.5\%$에서 각각 최대의 증식율을 보였다. 그리고 항생제 (colistin, erythromycin, bacitracin, tetracycline, penicillin)에 대해서 내성을 나타내었다. 자외선(30W, 50m)에 대해서는 상당히 내성이 약했으며, 70초간 조사 후에는 검출이 되지 않았다. 열에 의한 치사율은 $50^{\circ}C$에서 5.7분, $60^{\circ}C$에서 2.1분, 그리고 $70^{\circ}C$에서는 0.7분 만에 최초균수의 $90\%$이상이 사멸하였다.

• 문화기술의 융합
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• 제9권3호
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• pp.861-866
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• 2023

화학비료와 넓은 공간이 있어야 하는 기존의 스마트팜과 달리, 수생생물과 작물간의 공생 관계를 활용하여 환경오염 및 기후 변화 등의 비정상적인 환경에서도 작물 재배가 가능한 아쿠아포닉스 농법이 활발하게 연구되고 있다. 해당 농법은 작물마다 생장에 필요한 환경과 영양분이 다르므로, 생장에 최적화된 수생생물 비율을 구성이 필요하다. 본 연구는 아쿠아포닉스 환경에 영상처리 기법을 활용하여 면적과 부피를 기준으로 생육 정도를 측정하는 방법을 제안한다. 배설물을 통해 유기물 생성하는 여러 종류의 민물고기와 상추 작물을 아쿠아포닉스 환경에 생육을 통해 검증하였다. 상추의 2D와 3D 영상 분석과 실시간 데이터 분석을 통해 상추의 면적 및 부피 정보를 활용하여 생장 정도를 평가하였다. 실험 결과, 상추의 면적과 부피 정보를 활용하여 재배관리가 가능하다는 것을 입증하였다. 수생생물과 생육 정보를 활용하여 농업인에게 생산 예측 서비스 제공과,변화하는 농업 환경에서의 문제점을 해결하는 시작점이 되어줄 것으로 보인다.

• 한국환경보건학회지
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• 제44권2호
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• pp.133-142
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• 2018

Objectives: The pathogenic Vibrios genus denotes halophilic bacteria that are distributed in aquatic environments, including both sea and freshwater. Vibrio cholerae, Vibrio vulnificus, and Vibrio parahaemolyticus are the most important species since they can be potent human pathogens and leading causes of septicemia, wound infections, and seafood borne gastroenteritis. The recent emergence of a potential pandemic clone, V. cholera serotype O1 and the cholera outbreak in South Korea in 2016 indicates the importance of consistent surveillance of pathogenic Vibrio genus within coastal areas. Methods: The present study was undertaken to determine where and how vibrios live in the aquatic environment adjacent to coastal areas of South Korea. For this survey, a total of 838 samples were obtained at 35 different sites in South Korean coastal areas during the period from January 2016 to December 2016. Pathogenic vibrios was determined using the real-time PCR method, and its clones were isolated using three selective plating media. We also monitored changes in seawater and atmospheric temperature, salinity, turbidity, and hydrogen ion concentration at the collection points. Results: The total isolation rates of V. vulnificus, V. cholera (non-pathogenic, non-O1, non-O139 serogroups), and V. parahaemolyticus from seawater specimens in 2016 were 14.2, 13.48, and 67.06%, respectively. Conclusions: The isolation rates of pathogenic vibrios genus showed a positive correlation with temperature of seawater and atmosphere but were negatively correlated with salinity and turbidity.

• Fisheries and Aquatic Sciences
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• 제19권9호
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• pp.41.1-41.7
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• 2016

Background: The transgenic approach using estrogen-responsive regulator in fish has been given much attention as a potential means to detect and/or address estrogen-related aquatic pollutions. In order to address the development stage- and reproduction status-dependent expression patterns of the chgH-rfp transgene (red fluorescent protein transgene driven by choriogenin H promoter) in marine medaka Oryzias dancena, naturally occurring red fluorescent protein (RFP) signals under non-exposed conditions as well as the transgenically induced RFP signals under estrogen-exposed conditions were assayed. Results: Female transgenics begun to show naturally occurring RFP signals from the age of 7 weeks post hatching (WPH) without experimental estrogen exposure. Afterward, these RFP signals in female transgenics became robust with the progress of ovarian maturation. On the other hand, male transgenics did not show any naturally occurring RFP signal under non-exposed conditions irrespective of developmental stages and maturation statue. Upon exposures using estradiol-$17{\beta}$ (E2) and $17{\alpha}$-ethinylestradiol (EE2), RFP signals were significantly induced specifically in the livers of transgenic males. Conclusions: Male chgH-rfp transgenics were able to keep the "off" state of RFP expression during their entire life cycle unless exposed to exogenous estrogens. Owing to their tight regulation capability of estrogen-responsive transgene, transgenesis of chgH-rfp in male marine medaka could offer a useful model system for future ecotoxicogenomic studies regarding estrogenicity-related issues in aquatic and marine environments.

• 한국수산과학회지
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• 제56권5호
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• pp.626-633
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• 2023

Vibrio spp. are aquatic bacteria that are ubiquitous in warm estuarine and marine environments. Especially, V. vulnificus and V. cholerae are currently known to cause potentially fatal infections in humans. This study investigated the distribution and antibiotic resistance of V. vulnificus and V. cholerae isolated from coastal areas of Gyeongsangnam-do in 2022. A total of 252 samples of water, shellfish and coastal sediment were collected from 7 locations along the coast, and 124 samples of fishery products were collected from markets. Among the 252 samples, forty-four V. vulnificus (11.7%) and fourteen V. cholerae non-O1/non-O139 (3.7%), none of which carried the ctx gene, were isolated. Out of the 124 samples, 6 (4.8%) tested positive for V. vulnificus and V. cholerae was not detected. The isolation rates of V. vulnificus and V. cholerae showed a significant correlation with environmental factors such as seawater temperature and salinity. In an antibiotic resistance test, V. vulnificus was susceptible to amikacin, gentamicin, imipenem trimethoprim/sulfamethoxazole, and ciprofloxacin, but resistant to cefoxitin (100.0%), followed by tetracycline (9.1%). Multidrug resistance was also observed. Continuous monitoring of Vibrio pathogens with water temperature and salinity is expected to help reduce the outbreaks, and rational use of antibiotic agents is needed to prevent the accession of antibiotic-resistant microorganisms in aquatic ecosystems.

• 한국조경학회지
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• 제27권3호
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• pp.1-17
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• 1999

The purpose of this study is to evaluate the creation techniques of artificial wetland, one of biotopes developed to promote biodiversity in urban areas, and to look for improvement steps. Specifically, artificial wetland creation techniques were categorized into living environment and living creature classification. Being living conditions for creations, habitat environment was reviewed with a focus on water and soil environments. Living creatures were classified into plants, insects, fish, and birds. The evaluation of creation techniques was done in post-construction evaluation while considering the creation of habitats for living creatures. Intervention by users, changes in living environment and living species, and relevance of creation techniques were reviewed. Key results of this study are as follows. (1) Water environment for the living environment of creatures provides a suitable environment conditions for the living of creatures through a process easing the use of piped water. Various water depths and embankment appear to have a positive impact on the living of aquatic life. In particular, embankment covered in soil naturally played an important role as a place for the activities of aquatic insects and young fish as well as the growth of aquatic plants. (2) Various aquatic and ground plants to promote insect-diversity, shallow water, and old-tree logs had contributed greatly in increasing the types and number of insects. Aquatic insects. Aquatic insects were seen much particularly in areas where aquatic plants are rich but water is shallow than any other areas. (3) A space piled with stone to provide habitats for fish was not much used. However, it was observed that fish used embankment built with natural stones and embankment using logs in areas where water is deep. In addition, it was confirmed that 1,500 fish that had been released propagated using various depths and places for birth. (4) It was analyzed that techniques (creation of island, log setting, and creation of man-made bird nests) to provide habitats and to attract birds are not serving their roles. In such a case, it is believed that species had not increased due to the smallness as well as isolated features of the area. Based on theoretical review, they are judged to be areas that are likely to be used when a greater variety of birds is introduced. It is judged that attracting and keeping more birds at the site, such spaces need to be linked systematically in the future in terms of building eco-network while ensuring an adequate living areas. (5) In the study areas, users intervened greatly. As a result, a blockage was created preventing the normal growth of plants and non-indigenous plants were introduced. In order to limit the intervention by users, setting enough buffer zones, and environment education programs were urgently required. D/H=1>Hyangkyo> houses on the river>temples>lecture halls. D/H ratio of the backside areas is as follows. D/H=1>Hyangkyo>houses on the river>lecture halls. 4. Inner garden were planted deciduous than evergreen trees with Lagerstroemia indica. Enclosed dominant trees were planted by Pinus densiflora, Querces seuata. construct GEM strain, and examined for the expression and functional stability in microcosms.