• Archives of Pharmacal Research
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• 제23권2호
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• pp.139-146
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• 2000

7- Bromomethylbenz[a]anthracene is a known mutagen and carcinogen. The two major DNA adducts produced by this carcinogen, i.e., $N^2$-(benz[a]anthracen-7-yl methyl)-2'-deoxyguanosine (2, b[a]$a^2$G) and $N^6$-(benz[a]anthracen-7-ylmethyl)-2'-deoxyadenosine (4, b[a]$a^6$/A), as wel 1 as the simpler benzylated analogs,$N^2$-benzyl-2'deoxyguanosine (1, $bn^2$G) and $N^6$-benzyl-2'-deoxyadenosine (3, $bn^6$/A), were prepared by direct aralkylation of 2'-deoxyguanosine and 2'-deoxyadenosine. To determine the site-specific mutagenicity of these bulky exocyclic amino-substituted adducts, the suitably protected nucleosides were incorporated into 16-base oligodeoxyribonucleotides in place of a normal guanine or adenine residues which respectively are part of the ATG initiation codon for the lac Z' \alpha-complementation gene by using an in situ activation approach and automated phosphite triester synthetic methods. The base composition and the incorporation of the bulky adducts into synthetic oligonucleotides were characterized after purification of the modified oligonucleotides by enzymatic digestion and HPLC analysis.

• The Korean Journal of Ecology
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• 제15권1호
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• pp.67-73
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• 1992

This study was carried out to investigate the effects of soil improver on the population density and composition of microarthropods in the upland which cultivated pepper consecutively. We have treated soil improver sucf as zeolite, compost, ca, sio2 , and integrated improvement i. e. treated zeolite, compost, ca, and deep cultivate ; 20 cm. We sampled soil to collect soil microarthropods from a week to 15 months after treament at each site by soil-corer and extracted 48 hours in berlese- tullgren funnel. We have classified 16 families, 35 species diversity index of soil microarthropods are highe in the integrated improver and compost site than those found in any other sites. We suggest that soil improvement effrcts of integrated improved site are influenced by compost.

• Bulletin of the Korean Chemical Society
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• 제16권9호
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• pp.873-885
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• 1995

The local structural and thermodynamical properties of blends A-B/H of a diblock copolymer A-B and a homopolymer H are studied using the polymer reference interaction site model (RISM) integral equation theory with the mean-spherical approximation closure. The random phase approximation (RPA)-like static scattering function is derived and the interaction parameter is obtained to investigate the phase transition behaviors in A-B/H blends effectively. The dependences of the microscopic interaction parameter and the macrophase-microphase separation on temperature, molecular weight, block composition and segment size ratio of the diblock copolymer, density, and concentration of the added homopolymer, are investigated numerically within the framework of Gaussian chain statistics. The numerical calculations of site-site interchain pair correlation functions are performed to see the local structures for the model blends. The calculated phase diagrams for A-B/H blends from the polymer RISM theory are compared with results by the RPA model and transmission electron microscopy (TEM). Our extended formal version shows the different feature from RPA in the microscopic phase separation behavior, but shows the consistency with TEM qualitatively. Scaling relationships of scattering peak, interaction parameter, and temperature at the microphase separation are obtained for the molecular weight of diblock copolymer. They are compared with the recent data by small-angle neutron scattering measurements.

• Journal of Microbiology and Biotechnology
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• 제32권10호
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• pp.1275-1283
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• 2022

Understanding soil microbial community structure in the Arctic is essential for predicting the impact of climate change on interactions between organisms living in polar environments. The hypothesis of the present study was that soil microbial communities and soil chemical characteristics would vary depending on their associated plant species and local environments in Arctic mature soils. We analyzed soil bacterial communities and soil chemical characteristics from soil without vegetation (bare soil) and rhizosphere soil of three Arctic plants (Cassiope tetragona [L.] D. Don, Dryas octopetala L. and Silene acaulis [L.] Jacq.) in different local environments (coal-mined site and seashore-adjacent site). We did not observe any clear differences in microbial community structure in samples belonging to different plant rhizospheres; however, samples from different environmental sites had distinct microbial community structure. The samples from coal-mined site had a relatively higher abundance of Bacteroidetes and Firmicutes. On the other hand, Acidobacteria was more prevalent in seashore-adjacent samples. The relative abundance of Proteobacteria and Acidobacteria decreased toward higher soil pH, whereas that of Bacteroidetes and Firmicutes was positively correlated with soil pH. Our results suggest that soil bacterial community dissimilarity can be driven by spatial heterogeneity in deglaciated mature soil. Furthermore, these results indicate that soil microbial composition and relative abundance are more affected by soil pH, an abiotic factor, than plant species, a biotic factor.

• 대한건축학회논문집:계획계
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• 제35권11호
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• pp.61-68
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• 2019

The analysis of outdoor and indoor spatial composition with natural elements is required for the creation of healing environment in healthcare facility to provide basic data for the planning of hospital architecture. Literature review of healing environment and investigation on characteristics of spatial composition in architectural works and healthcare facilities have been conducted. The spatial composition of outdoor space for refuge and prospect from indoor space of Seoul National University Hospital have been analyzed. The result of this research can be summarized as followed. First of all, the main natural elements for healing environment are consisted with refuge in outdoor space and prospect from indoor space. The second one is that natural elements in Seoul National University Hospital are located in central, posterior, and lateral area of main hospital and connectivity, integration, and ERAM(3) which the characteristics of outdoor spatial composition with space syntax are focused on the museum of medicine and landscape area in the center of hospital. The third one is that the outdoor refuge and prospect from indoor space in Seoul National University Hospital can be replaced with cultural heritage like the site of Kyungmogungji and Changgyeonggung palace in and next to the hospital. In addition to the outdoor and indoor spatial composition, it is necessary to analyze the relationship between elements to develop the healing environment of hospital architecture.

• 한국수산과학회지
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• 제33권1호
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• pp.1-8
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• 2000

본 조사는 1995년 8월부터 1996년 2월까지 계절별로 3차례에 걸쳐 통영주변 가두리 밑의 환경 및 저서동물 군집조사를 통해 가두리 운영에 따른 저서생물 군집구조의 변화를 알아보기 위해 실시되었다. 조사지역의 가두리 밑은 주변 해역과 유사한 퇴적상과 용존산소량을 나타낸 반면 높은 유기물 함량을 나타냈다. 종 수의 경우 가두리 밑이 대조구에 비해 적었지만 서식밀도에서는 현저히 높게 나타났다. 가두리 밑의 경우 Capitella capitata 와 Nebalia bipes등이, 대조구의 경우 Lumbrineris longifolia와 Amphioplus sp.가 우점 종을 나타냈다. 특히 가두리 밑에서는 Asterina pectinifera와 Asterias amurensis 등 표서성 초대형저서동물의 서식밀도가 높게 나타났다. 다양도에서 가두리 밑은 계절적인 차이를 보인 반면, 대조구는 차이를 나타내지 않았다. 군집구조에서 가두리 밑과 대조구는 상이한 구조를 나타냈다. 본 조사결과 가두리 양식은 유기물 증가와 시설물에 의한 유해 패각 가입 등 생물학적 영향에 의해 가두리 밑 저서환경과 저서동물 군집구조에 영향을 미치는 것으로 나타났다.

• 한국수산과학회지
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• 제37권6호
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• pp.469-477
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• 2004

This study examined distributional patterns of Asterias amurensis in Tongyeong, the central South Sea of Korea. The density of the sea star was estimated at 10 chosen sites in the inner and the outer parts of the Tongyeong coast from December 2000. The mean density of the species in this area was $2.4ind./m^{2}$. The seasonal surveys conducted at 3 arbitrary chosen sites (i.e., sea cage, reef and soft sediment) also showed that the abundance of the species at the sea cage site $(density:\;3.6\;ind./m^{2};\;biomass:\;250.7\;gwwt/m^{2})$ was significantly higher than at the reef site $(density:\;1.7\;ind./m^{2};\;biomass:\;63.5\;gwwt/m^{2})$ and the soft sediment site $(density:\;0.4\;ind./m^{2};\;biomass:\;18.9\;gwwt/m^{2})$. Densities were higher at sea cages areas than at reefs and soft bottom sites. At sea cage site, A. amurensis population exhibited a strong aggregated distributional pattern. In contrast, at reef and soft bottom sites, A. amurensis population showed a random distributional pattern. The spatial difference in prey species and its abundance was the primary factor determining the spatial heterogeneity of the sea star in its behavior characteristics. Experiments on the feeding preference indicated that A. amurensis had a strong selectivity on its prey, but this selectivity varied between populations living in different sites. In particular, A. amurensis populations at the reef site showed a strong selectivity on various sessile and mobile animals living in reef areas, suggesting that these animal groups may play a role as "windows for the survival of A. amurensis". These results suggest that the distribution of A. amurensis in Tongyeong is closely associated with abundance of prey species and the bottom composition.

• 고문화
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• 36호
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• pp.23-46
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• 1990

We have examined 10 samples of neolithic pinched potteries from Tongsam-dong site to find out the composition of paste and the firing temperature through scientific methods. We made thin sections of shards and observed them under a polarizing microscope.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 춘계학술대회 논문집
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• pp.400-401
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• 2008

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 추계학술대회 논문집
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• pp.253-254
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• 2008