• 미생물학회지
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• 제17권2호
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• pp.65-71
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• 1979

On studying of microbes and appearance frequency which are floating around dwelling space and life environments in Seoul area, the results are summarized as follows ; 1. 1931 strains of 29 bacteria are isolated in dwelling spaces, Among them, there are Staphylococcus aureus, S. anthracis which are pathogenic to human beings. 2. In fungi, 76 strains of 13 species are isolated. That of highest frequency is confirmed to be Aspergillus which is pathogens of Aspergillosis (one of a group of diseases of animals and human being caused by various species of Aspergillus). The places, where the number of kinds and the frequency of appearances have been observed highest, are coffee shops, lunch counters and office rooms, while factory districts are of far lower level than expected. 3. 0.1% $HgCl_2$, Leasking oil, and Telephone disinfectant were better than any other in fungicidal effect.

• ALGAE
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• 제20권3호
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• pp.217-224
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• 2005

The species composition and biomass of marine algae at the discharge canals of three (Gori, Wolseong and Uljin) nuclear power plants on the east coast of Korea were investigated seasonally from February 1992 to October 2000. As a result, 103-107 species of marine algae were found at the discharge canals during the past nine years. In general, algal communities established at the discharge canals were less diverse than those at the intake canals and control sites. 43 species (6 blue-green, 9 green, 10 brown and 18 red algae) of marine algae occurred more than 1/6 frequency and thus can be categorized as warm tolerant species. Among these, two green (Urospora penicilliformis, Cladophora albida), four brown (Sphacelaria divaricata, S. rigidula, Sargassum coreanum, S. fulvellum) and four red algae (Stylonema alsidii, Bangia atropurpurea, Hypnea charoides, Chondria crassicaulis) are recorded as warm tolerant marine algae for the first time in Korea during this study. Enteromorpha compressa, Padina arborescens, Amphiroa zonata and Ahnfeltiopsis flabelliformis were common species found more than 50% frequency at the discharge canals of all three nuclear power plants investigated. Dominant species in biomass were Padina arborescens and Amphiroa zonata. Results showed that, as a whole, the red algae appeared as predominant algal group at the discharge canals of all three nuclear power plants on the east coast of Korea. However, the biomass proportion of dominant algae at the discharge canals of each nuclear power plant varied over the year during the past nine years.

• 수산해양기술연구
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• 제52권2호
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• pp.111-120
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• 2016

Acoustic surveys using a scientific echosounder and trawl surveys were concurrently carried out in between Geoje and Tongyeong of the South Sea by season. The anchovy schools were identified by trawling in each station and used for frequency response analysis. Frequency responses of anchovy schools by season and species composition ratio were examined using multi-frequencies (18, 38, 70, 120 and 200 kHz). The frequency response r(f), is one of the acoustic characteristics which means the volume back-scattering strength ratio between a reference frequency and other frequencies. In spring, the r(f) of anchovy schools decreased with increased frequency, with the exception of 120kHz. While, in winter, the r(f) continuously decreased inversely proportional to the increase in frequency. Frequency response of anchovy schools presented a distinctive difference between spring and winter, however it did not different in spife of different species composition ratios in schools.

• 한국식품과학회지
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• 제34권5호
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• pp.862-866
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• 2002

분말상태의 인삼속 식물들의 품종 및 원산지를 판별하기 위하여 SAW 센서가 내장된 PHGC를 이용하여 향기 패턴을 분석하였다. 한국 백삼을 1로 기준할 때 전체적인 Rt에 대한 frequency pattern의 면적비는 화기삼 $0.248{\sim}0.871$, 전칠삼 $0.030{\sim}0.674$, 중국산 백삼 $0.005{\sim}0.212$ 범위로 나타났다. 분명한 차이를 나타내는 몇 개의 특정 향기성분의 면적비를 보면 $Rt_{20.02}$에서 한국산 백삼 1일 때, 중국산 백삼 0.212, 화기삼 0.343, 전칠삼 0.065이었다. 또한 $Rt_{21.70}$과$Rt_{24.90}$에서 검출되는 향기성분의 면적비도 품종간의 차이가 뚜렷하였다. 한국산 백삼과 중국산 백삼에서 검출된 Rt_26.15 향기성분의 면적비는 각각 1과 0.185로 나타나 원산지간의 차이도 분명히 나타났다. $Rt_{26.15}$의 향기성분은 화기삼과 전칠삼에서는 검출되지 않았다. Frequency pattern, derivative pattern을 Vapor $print^{TM}$을 사용하여 도형화하여 비교한 결과 한국 백삼(Korean Panax ginseng C.A. Meyer), 화기삼(미국삼, 서양삼, Panax quinquefolium L.), 전칠삼(Panax notoginseng F.H. Chen), 중국산 백삼(Chinese Panax ginseng)은 서로 다른 패턴을 보여주어 품종간의 차이는 물론 원산지의 차이도 뚜렷하게 나타났다.

• Journal of Ecology and Environment
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• 제31권2호
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• pp.147-151
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• 2008

Feeding methods of five species of herons and egrets were studied in an agricultural landscape in Asan city, Chungcheongnam-do, Korea in 2006. Grey herons primarily hunted while standing, whereas great egrets fed while walking slowly. Two smaller species, little and cattle egrets, were active foragers, feeding both while walking quickly and walking slowly. Little egrets were the only species using the foot stirring method. The medium-sized heron, intermediate egrets, foraged mainly while walking slowly or leaning. For grey herons, great egrets and little egrets, the frequency of use of different feeding methods was different between habitats: these species used the leaning method more frequently in rice fields than in reservoirs and ditches. Also, most herons (all species other than great egrets) showed seasonal changes in their feeding methods that are related to changes in habitat condition.

• 아시안잔디학회지
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• 제10권1호
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• pp.89-101
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• 1996

Seventeen dictyostelids occurred in the southern mountains in Korea. Total clones per site was 7,491 and average number of species was 7.6. Dominant species in the each mountains were as follow; Dityostelium firmibasis in Kayasan, D. minutum in Kyeryongsan, D. firmibasis in Naejangsan, D. brefeldianum in Dukyusan, D. microsporum in Palgougnan, P. pallidum in Tohamnan, P. pallidum in Koryong. However, dominant species was D. brefeldianum in the southern mountains. Average frequency, relative density and presence were impartially high in all sites. It wan not dominant except Dukyusan. And it had not been reported to he common species until now in Korea. D. mucoroides an wan not dominant species in all sites, it wan the dominant species second to D. brefeldianum.

• International Journal of Oral Biology
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• 제43권4호
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• pp.209-216
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• 2018

Reactive oxygen species (ROS) and nitrogen species (RNS) are involved in cellular signaling processes as a cause of oxidative stress. According to recent studies, ROS and RNS are important signaling molecules involved in pain transmission through spinal mechanisms. In this study, a patch clamp recording was used in spinal slices of rats to investigate the action mechanisms of $O_2{^{{\bullet}_-}}$ and NO on the excitability of substantia gelatinosa (SG) neuron. The application of xanthine and xanthine oxidase (X/XO) compound, a ROS donor, induced inward currents and increased the frequency of spontaneous excitatory postsynaptic currents (sEPSC) in slice preparation. The application of S-nitroso-N-acetyl-DL-penicillamine (SNAP), a RNS donor, also induced inward currents and increased the frequency of sEPSC. In a single cell preparation, X/XO and SNAP had no effect on the inward currents, revealing the involvement of presynaptic action. X/XO and SNAP induced a membrane depolarization in current clamp conditions which was significantly decreased by the addition of thapsigargin to an external calcium free solution for blocking synaptic transmission. Furthermore, X/XO and SNAP increased the frequency of action potentials evoked by depolarizing current pulses, suggesting the involvement of postsynaptic action. According to these results, it was estblished that elevated ROS and RNS in the spinal cord can sensitize the dorsal horn neurons via pre- and postsynaptic mechanisms. Therefore, ROS and RNS play similar roles in the regulation of the membrane excitability of SG neurons.

• 한국환경복원기술학회지
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• 제20권2호
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• pp.37-59
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• 2017

The Korean peninsula belongs to the temperate forest biome dominated by many deciduous oaks. We quantitatively and qualitatively studied vertical and horizontal distributions and habitat characteristics on the major oak species such as Quercus mongolica, Q. serrata, Q. variabilis, Q. dentata, Q. aliena and Q. acutissima. A total of 5,278 samples were analyzed with a species coverage and 6 principal environmental variables extracted from public database of nationwide natural environment survey. Correlation analysis was accomplished by the CANOCO using Canonical Correspondence Analysis and the Pearson correlation coefficient using PASW Statistics. The hierarchical distribution tendency of six oaks was finalized using the Goodman-Kruskal lambda coefficient of non-metric multidimensional scaling by SYN-TAX 2000. The utmost factor on the distributional segregation of oak species was the elevation, i.e. temperature. Q. serrata and Q. mongolica show clearly a diametrical distribution patterns with zonal distribution. Q. variabilis was determined as a thermophilic and xerophilous species that is a component of not only natural pseudo-climax forest but also secondary forest. The highest frequency of the dominant forest was found Q. mongolica. Whereas, Q. serrata showed the highest frequency of individual tree but the relatively lower frequency of dominant forest, which is resulted from the original habitat loss. By the benefit of the traditional Soopjeong-E, Q. acutissima dominant forests were remained rather largely. Individuals of Q. dentata occurred horizontally nationwide, but its dominant forest was the poorest. Dominant forest of Q. aliena, which is a natural vegetation, was the most rare due to a limited potential habitat.

• 한국대기환경학회지
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• 제15권4호
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• pp.393-402
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• 1999

Precipitation samples were collected by the wet-only sampling method in Iksan in the northwest of Chonbuk from March 1995 to February 1997. These samples were analyzed for the concentration of ion components, in addition to pH and electrical conductivity. The annual mean pH of precipitation was 4.8 and the seasonal trend of pH was shown to be low in Fall and Winter(4.5), middle-ranged in Spring(4.7) and high in Summer(5.0). The frequency of pH below 5.6 was about 71%. The seasonal pattern of pH frequency was found to be different in each season. In the case of the pH less than 5.0, the frequency was higher in Spring, Fall and Winter than in Summer, especially higher in Fall than in other seasons. The concentrations of analysed ions showed a pronounced seasonal pattern. However, major ion species for all seasons were $NH^+_4,;Ca^{2+};and;Na^+$ among cations and $SO^{2-}_4,;Cl^-;and;NO^-_3$ among anions. The major acidifying species appeared to be $nss-SO^{2-}_4;and;NO^-_3$, and the main bases responsible for the neutralization of precipitation acidity were $nss-Ca^{2+};and;NH^+_4$. The potential acidity of precipitation, pAi, was found to be between 3.0 and 5.0 for total samples, while the measured pH was approximately between 3.9 and 7.8. The seasonal trend of pAi showed a decreasing order: Summer (4.3), Winter(4.0), Spring and Fall(3.8). During the Fall, both pAi and pH were especially very low, which indicated that during this period the potential acidity of precipitation was high but the neutralizing capacity was low. For Spring, pAi was very low but pH was slightly high. This was likely due to the large amount of $CaCO_3$ in the soil particles transported over a long range from the Chinese continent that were incorporated into the precipitation, and then neutralized the acidifying species with its high concentraton.

• 한국환경생태학회지
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• 제2권1호
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• pp.19-36
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• 1988

치악산국립공원의 주연부 식생구조 및 출현수종을 밝히기 위해 1988년 7월-9월 사이에 현지조사를 한 결과는 다음과 같다. 수관선형, 수간선형 및 전진형 주연부식생이 나타나고 있었으며, 주연부에서 삼림내부로의 거리에 따른 출현수종들이 수관층위별 상대우점치 변화가 방위와 기존 상층우점수종별로 달랐다. 특히, 남사면의 소나무림 내부에서 주연부 양수들이 우세하게 출현하고 있었으며, 북사면 계류 주연부에서는 호습성수종들이 양수들과 함께 우세하게 출현하였다. 삼림주연부로부터 삼림내부로의 거리가 증가할 수록 수관층위별 종수 및 개체수, 종다양도 및 상이도는 감소하는 경향을 나타냈으며, 주연부깊이는 15-20m로 나타났다. 환경유형별 관목층과 임상층의 주연부우점수종은 고도와 지형적 위치 즉, 계곡부, 능선, 정상부에 따라 달랐으며 특히, 정상부의 주연부 우점수종은 독특하였다. 그리고 고도, 지형적 위치 및 방위가 주연부식생간의 유사도에 영향을 미치는 것으로 나타났다. 고도, 방위 및 지형적위치에 따라 주연부 수종들의 출현빈도계급이 달랐으며, 병꽃나무는 전지역에서 높은 출현빈도를 나타냈으며 병꽃나무, 신갈나무, 물푸레나무, 다래, 산딸기, 소나무, 생강나무, 노린재나무, 두릅나무는 대체적으로 전지역에서 주연부 수종으로 출현했다.