• 한국미생물·생명공학회지
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• 제46권2호
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• pp.135-144
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• 2018

The rapid increase in number and diversity of Extended Spectrum ${\beta}$-Lactamases (ESBLs) producing Enterobacteriaceae in natural aquatic environment is a major health concern worldwide. This study investigates abundance and distribution of ESBL producing multidrug resistant Enterobacteriaceae and molecular characterization of ESBL genes among isolates from highly polluted stretch of river Yamuna, India. Water samples were collected from ten different sites distributed across Delhi stretch of river Yamuna, during 2014-15. A total of 506 non duplicate Enterobacteriaceae isolates were obtained. Phenotypic detection of ESBL production and antibiotic sensitivity for 15 different antibiotics were performed according to CLSI guidelines (Clinical and Laboratory Standard Institute, 2015). A subset of ESBL positive Enterobacteriaceae isolates were identified by 16S rRNA gene and screened for ESBL genes, such as $bla_{CTX-M}$, $bla_{TEM}$ and $bla_{OXA}$. Out of 506 non-duplicate bacterial isolates obtained, 175 (34.58%) were positive for ESBL production. Susceptibility pattern for fifteen antibiotics used in this study revealed higher resistance to cefazolin, rifampicin and ampicillin. A high proportion (76.57%) of ESBL positive isolates showed multidrug resistance phenotype, with MAR index of 0.39 at Buddha Vihar and Old Delhi Railway bridge sampling site. Identification and PCR based characterization of ESBL genes revealed the prevalence of $bla_{CTX-M}$ and $bla_{TEM}$ genes to be 88.33% and 61.66%, respectively. Co-occurrence of $bla_{CTX-M}$ and $bla_{TEM}$ genes was detected in 58.33% of the resistant bacteria. The $bla_{OXA}$ gene was not detected in any isolates. This study highlights deteriorating condition of urban aquatic environment due to rising level of ESBL producing Enterobacteriaceae with multidrug resistance phenotype.

• Ocean and Polar Research
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• 제25권1호
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• pp.21-30
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• 2003

Seasonal fluctuations of physico-chemical and biological aspects of the environment were studied in Vladivostok harbour (Golden Horn Bay, the East Sea/Sea of Japan). The benthic community structure was described with a focus on size-spectra (bacteria, meio- and macrofauna) related with the chemical environment and chemical fluxes in sediment and to reveal their possible ecological role in the process of bioremediation of the environment. Samples from two sites with different concentrations of heavy metals (Fe, Zn, Cu, Pb, Mn, Cr, Ni Cd, Co) and petroleum hydrocarbon were assessed by a number of methods. These included plate counts of culturable bacteria, observation through a scanning electron (SEM) and transmission electron microscope (TEM). These approaches were complemented with microscopic assessments of the diversity of the benthic community. The specific communities had a limited number of species, tolerant to abnormally high levels of toxic compounds. The dominant species were presented by several sho.1-lived small polychaetes (Capitella capitata) and nematodes (Oncholaimium ramosum). The highest population density was recorded in microbenthos, in various diatoms, various physiological groups of bacteria which participate in biomineralization: marine heterotrophic bacteria, which oxidized oil, black oil in addition to groups resistant to heavy metals. They have the entire set of mechanisms for neutralizing the negative effect of those compounds, forming the detrital food web and biogeochemical circulation of material in sediments, which results in the biological self-recycling of sea basins. Macro- and meiobenthic organisms were more sensitive to a greater extent of $H_2S$ and petroleum hydrocarbons than to metal content, but the within-site rankings were the same as those achieved for microbiological analyses.

• Ocean and Polar Research
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• 제30권3호
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• pp.261-275
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• 2008

The profile of a fixed site at station M ($34.77^{\circ}N,\;129.13^{\circ}E$) in the Korea Strait was studied from March 2006 to February 2007. The aim was to understand the relationship between the annual thermal stratification pattern and seasonal variation in phytoplankton community structure. Physicochemical factors including temperature, salinity and nutrient concentrations, which strongly influence the proliferation and diversity of phytoplankton, were measured. The study period was divided into three due to the characteristic of thermohaline structures; mixed I (March-May 2006), stratified (June-November 2006) and mixed II(December 2006-Feburuary 2007). Diatoms dominated during the mixed I (89%) and II (48%) periods, while nanoplankton group occupied over 83% of total population during the stratified period. The dominant species during the mixed I and II was Chaetoceros socialis (47% and 29%, respectively), while during the stratified period Gyrodinium sp.(4%) was the most dominant. Averaged total chl a concentrations during the mixed I and II periods were 0.61 mg $m^{-3}$ and 0.72 mg $m^{-3}$, respectively, which were at least two-fold higher than that during the stratified period (0.30 mg $m^{-3}$). The vertical mixing and convection process of the water column induced nutrient supply from the bottom layer to the euphotic zone. It also led to the dominance of diatoms during the mixed periods, whereas small phytoplankton prevailed over large phytoplankton as stratification blocked the upward movement of nutrients to subsurface during the stratified period. During the mixed I and II periods, microplanktonic chl a dominated concentrations (50% and 48%, respectively), while picoplanktonic chl a occupied over 37% of total chl a during the stratified period.

• 한국조경학회지
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• 제30권6호
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• pp.66-78
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• 2003

The purpose of this study was to minimize the forest disturbance around an entry road of a power transmission tower construction site between Taean and Sinsesan, Chungnam. The main study field was classified into existing materials and a GIS, remote sensing analysis, and a field examination. This information was used to identify the most suitable entry road using a degree of green naturality map, eco-naturality map, actual vegetation map, and a forest state map as the existing materials. Also, the study used an normalized difference vegetation index, altitude and slope map in order to make the evaluation materials which used an remote sensing image, and GIS. This data was used to choose an optimum area, and diagnosed the current condition of the vegetation with a field survey of the area. It analyzed vegetation structure, species diversity, the age of trees in a field examination. Subsequently, we proposed four area types based on the analysis results--preservation area, transplantation area, restoration area and development area. As a result, the preservation area was categorized into 8 grades, according to the degree of green naturality, large area of breast diameter at Pinus densiflora community, competition area of Pinus densiflora and Quercus spp. and Quercus spp. community of over 20 years old. A transplantation area established 46 optimum areas according to the GIS analysis and vegetation investigation results. Vegetation restoration plan for disturbance area should be made based on ecological value of existing vegetation to worthwhile area as Quercus spp. mixing forest proposed. The development area selected a ecological worthless place as an artificial forest where Pinus densiflora and Pinus thunbergii growth is poor. This research results suggest that restoration of vegetation will be possible in the real world. Also, ecological restoration guidelines will be made through building and analyzing data base and routine monitoring of transplantation and restoration area.

• 환경위생공학
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• 제14권4호
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• pp.50-68
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• 1999

The present study was performed to examine on the fauna and standing crops of benthic macroinvertebrates in Pongwha and Youngwol region of upper parts of south han river and Naktons river. The Actual site suvry was caried out on the two times during the April·June to October·November, 1988. Main five areas are Mt. Awrawe(1,067m), Mt. Sontal (1,236m), Mt. Munsu(1,206m), Peak Okyopong(357m) and Mt. Pungnak(760m) area. Total taxa of benthic macroinvertebrates of the study area were 118 species, 45families12 orders, 5 classes in 4 phyla. Occurrence species according to the major taxa of aquatic insects were 35 species (29.66%) in ephemeroptera, 25 species(21.19%) in trichoptera, 25 species(21.19%) hemiptera, 1 species(0.85%) in megaloptera. Non-aqautic insect were 5 species in mollusca, 3 ratio was 8.5 percent. Occurrence species(plecoptera) at clean waters were appeared 12 species at Mt. Awrawe and Sontal area. Occurrence species at each survey area was 67 species at Mt. Awrawe area, 60 species at Mt. Sontal area, 43 species at Mt. Munsu area, 37 species at Mt. P'ungnak area and 34 species at Peak Okyo area, respectively. Species diversity indices were 2.96~3.80 at Mt. Awrawe area, 2.79~3.62 at Mt. sontal area, but 2.64~3.12, 1.59~2.46 and 1.98~2.59 at, Mt. Munsu, P'ungnak and Peak Okyo area, respectively. In this region, occurrence species and individual density were smaller than that of Dong river with good habitat, but those were more abundant than that of Poseong river with similar environment conditions. Therefore, occurrence species and individual density of the present survey region were appeared as somewhat abundant.

• 한국환경교육학회지:환경교육
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• 제10권2호
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• pp.249-268
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• 1997

This Study developed 'Environment Management Integrated Leader(EMIL)' program and evaluated the effect of the Program. The procedure of EMIL program development is as follows; 1) Identifying the training needs Through the interview and discussion with corporate environmental staff and research members, training need are collected. 2) Setting the training objectives 30 objectives are developed through specifying and organizing the training needs. 3) Determining the scopes of the program This program consists of the four scopes. First, the scope of Environmentally Acceptable Management is developed based on ISO 14000 and certification of environmentally friendly business. Second, the scope of Environmentally Acceptable Technology includes air pollution, water pollution, solid wasted management, and pollution prevention. Third, the scope of Integrated Environmental Management focuses on master plan, green marketing, green production, and green accounting. Finally, the scope of Integrated Environmental Concepts focuses on food pollution, environmental activities, and bio-diversity. 4) Selecting the training methods Various methods are used such as off-site visits, exercises, case study, workshop, discussion, role-playing as well as lecture. 5) Implementing the program 49 trainees participated the program for 6weeks. All trainees are working for D. Company Group. 6) Measuring training effects To evaluate the effects of the program, pre-post training evaluation method is used. The results are highly significant at all 4 scopes by the p<.01. This study has some implications in order to establish the environmental management climate. First, the development of new environmental education program for management is necessary. Second, Vast investment are required. Third, more systematic approaches are desired in environmental education. Lastly, more customized program development and implementation to fit in industries will accelerate the expansion of environmental concept.

• Animal Systematics, Evolution and Diversity
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• 제28권3호
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• pp.215-219
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• 2012

To examine genetic divergences of two endemic Sorex caecutiens subspecies from Korea (S. c. hallamontanus in Korean Jeju Island and S. c. annexus in the mainland Korean Peninsula), we obtained partial cytochrome oxidase I (COI) sequences (429 bp) and complete cytochrome b sequences (1,140 bp) from the two Korean subspecies, and we compared these sequences to the corresponding sequences of S. caecutiens, obtained from GenBank. We found that Jeju S. c. hallamontanus is one of three clades within S. caecutiens, with an average Jukes-Cantor distance of 1.57% in the COI sequences and the distance of 2.07% and 11 fixed site differences in the cytochrome b sequences, indicating that Jeju S. c. hallamontanus is one endemic subspecies with concordant genetic distinctness, although further analyses with nuclear DNA sequences are necessary to confirm these findings. However, S. c. annexus from the mainland Korean Peninsula was not divergent from S. c. macropygmaeus from northeastern China and adjacent Russia, indicating that S. c. annexus from the mainland Korean Peninsula is another endemic subspecies with only morphological differences, although it is necessary to reexamine the subspecies status of S. c. annexus.

• The Korean Journal of Ecology
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• 제26권6호
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• pp.297-305
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• 2003

Fish fauna of mountain streams in the Jirisan National Park area of S. Korea (total area: 440.45 $\textrm{km}^2$, height: 1,915 m) was investigated at 33 sites from May 1997 to September 1999. A total of 4,670 individuals of fishes were collected and classified into 30 species and 12 families. Zacco temmincki (relative abundance (RA), 63.9%) was found to be the most abundant inhabitant. Subdominant species were Pungtungia hem (RA 6.2%), Zacco platypus (RA 6.1 %) and Coreoleusiscus splendidus (RA 4.8%). Among the total species, 13 species were identified as the Korean endemic species (7 families, 17.2% of 802 individuals). Dominant Korean endemic species was C. splendidus (relative abundance endemics (RAE), 27.8%). Superiors were Coreoperca heizi (RAE 21.8%) and Liobagrus mediadiposalis (RAE 19.8%). One exotic species (Oncorhynchus mykiss, a site and 5 ind.) and translated species (Hypmesus niponensis, two sites and 174 ind.) were collected in this survey. The proportion of Korean endemic species in the park (43.3%) was higher than the average of Korean Peninsular (25.9%). From this study, we conclude that the Jirisan National Park area in Korea would be very important for fish diversity and conservation, especially for the Korean endemic and endangered species.

• 한국통신학회논문지
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• 제27권1B호
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• pp.114-124
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• 2002

본 논문에서는 실내 전파환경에서의 페이딩을 분석하기 위하여 영상법 기반의 3차원 광선추적법에 패치산란모델을 첨가한 모델을 제시하였다. 영상법 기반의 광선추적법은 정확한 경로를 얻을 수 있다는 장점 때문에, 안테나의 빔패턴 및 편파, 그리고 전파의 진행에 따른 편파를 고려함으로써 페이딩 특성 분석이 가능하다. 또한 실내 구조물을 모델링하기 위한 패치산란모델은 패치형태의 직사각형 평면에 대한 RCS (Radar Cross Section)를 이용하여 입사에 대한 산란현상을 정의한 것으로써, 책상이나 테이블 같은 평면적인 실내 구조물에 대한 산란현상을 각각의 구조물에 대한 영상 안테나를 발생시키는 복잡한 과정 없이 간단하게 해석하기 위한 것이다. 제안된 모델은 신호강도 뿐만 아니라 채널의 페이딩 특성을 예측할 수 있기 때문에 안테나 종류별 편파 다이버시티 기법의 성능을 분석하는데 이용될 수 있다.

• 한국어류학회지
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• 제17권2호
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• pp.131-141
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• 2005

본 연구는 2004년 5월부터 2005년 2월까지 합천호를 중심으로 댐 내부에서 4곳, 댐 상 하류 하천에서 각각 1곳씩 모두 6개 지점을 중심으로 어류상을 조사 분석하였다. 그 결과 모두 12과 31속 36종으로 확인되었다. 본 조사 기간동안에 출현한 어류 가운데 우점종으로는 H. eigenmanni로 전체 어류의 28.4%의 출현률을 나타내었고, 아우점종으로는 H. labeo가 24.1%였다. 또한 출현한 어류 중 생산량이 가장 높은 어종은 H. labeo로서 전체의 36.5%의 비중을 차지하였고, 다음으로는 H. eigenmanni 22.3%, C. carpio 7.5%, H. nipponensis 6.9%의 순이었다. 합천댐 일대에서 종별 출현빈도가 가장 높은 분류군은 Cyprinidae 어류가 24종으로 전체의 66.7%였고, 그 다음으로는 Cobitidae와 Centropomidae가 각각 2종씩이고, 나머지는 1종씩이었다. 본 조사 구역에서 출현하는 우리나라의 특산어종은 모두 10종, A. koreensis, C. splendidus, S. gracilis majimae, S. chankaensis tsuchigae, M. yaluensis, H. eigenmanni, N. multifasciata, L. mediadiposalis, C. herzi, O. platycephala 등이며, 이 중 H. eigenmanni와 C. herzi는 출현 개체수가 많았으나, 그 외의 종은 비교적 희소하였다. 본 합천댐에서 출현하는 어류 중에서 외래어종은 C. carpio (Israeli), C. cuvieri, L. macrochirus이었고, 우리나라의 다른 하천에서 유입된 P. fulviraco가 확인되었다.