• 환경영향평가
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• 제9권4호
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• pp.339-348
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• 2000

This study was conducted to investigate the distribution pattern of plants on the streamside of Goggyochun, and to survey the distribution of heavy metal-contaminated soils and plants. A total of 11 survey sites were selected along the Goggyochun during the period of between June and September 1999. The wet land plants were composed of 44 species. The most frequently occurring species in the study sites were Rumex crispus, Persicaria hydropiper, Cyperus amuricus and Setaria viridis, and among them the Humulus japonicus, Erigeron canadensis and Phragnites communis species were dominants of the community. Analysis of soil properties showed that organic matter and clay contents were higher in the upstream region while sand content was higher in the downstream region. The pH and the organic matter contents of soils were at range of 6.70-9.94 and 2.39-15.16% respectively. The average contents of Pb and Cd in soils were 11.96mg/kg and 1.64mg/kg respectively, and these values were higher as compared with those of ordinary soil in Korea. The average contents of Zn and Pb in Persicaria hydropiper were 8.30mg/kg and 7.38mg/kg respectively, and these values were higher than other plants. The distribution of heavy metals in plants varied in accordance with the species regardless of the sites.

• 생태와환경
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• 제53권1호
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• pp.22-30
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• 2020

In this study, we investigated the relationships between benthic macroinvertebrate assemblages and various environmental factors in Iancheon (NIA) and Bukcheon (NBC) streams, Korea. We collected benthic macroinvertebrates and 33 environmental factors in April 2017 at 9 sites (5 sites in NIA and 4 sites in NBC). We identified 93 species(5 phyla, 9 classes, 16 orders, and 53 families) and 69 species(5 phyla, 9 classes, 17 orders, and 47 families) in NIA and NBC streams, respectively. Considering benthic macroinvertebrate index (BMI), NIA (88.2) and NBC (80.2) streams were in "very good" status. Upstream areas showed the highest scores, 95.5 (NIA1) and 94.2 (NBC1), whereas BMI score was the lowest in downstream areas of both streams, especially in NBC4 (51.0 "bad" status). Cluster analysis and non-metric multidimensional scaling analysis represented the differences of benthic macroinvertebrate assemblages according to spatial and anthropogenic gradients. Our findings provide reference data and highlight the need for the continued monitoring to maintain the good status and manage macroinvertebrate diversity in these two streams, in Sangju-si, Korea.

• Journal of Microbiology
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• 제39권1호
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• pp.37-41
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• 2001

The fission yeast Schizosaccharomyces pombe contains two distinct superoxide dismutase (SOD) activities, one in the cytosol encoded by the $sod2^{+}$ gene and the other in mitochondria. The $sod2^{+}$ gene encoding putative mitochondrial manganese superoxide dismutase (MnSOD) was isolated from the S. pombe genomic library using a PCR fragment as the probe. The nucleotide sequence of the $sod2^{+}$ gene and its flanking region (4051 bp HindIII fragment) was determined. An intron of 123 nt in size was predicted and confirmed by sequencing the cDNA following reverse transcription PCR. The predicted Sod2p consists of 218 amino acid residues with a molecular mass of 24,346 Da. The deduced amino acid sequence showed a high degree of homology with other MnSODs, especially in the metal binding residues at the active site and their relative positions. The transcriptional start site was mapped by primer extension at 231 at upstream from the ATG codon. A putative TATA box(TATAAAA) was located 58 nt upstream from the transcriptional start site and putative polyadenylation sites were located at 1000, 1062, and 1074 nt downstream from the ATG start codon.

• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.830-838
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• 2020

The histone-like nucleoid structuring protein (H-NS) is an abundant global regulator of environmentally controlled gene expression. Herein, we demonstrate that H-NS represses the expression of LeuO, the master regulator of the cyclic(Phe-Pro)-dependent signaling pathway, by directly binding to the upstream region of the gene. H-NS binds to a long stretched region (more than 160-bp long), which overlaps with binding sites for ToxR and LeuO. A high quantity of H-NS outcompetes ToxR for binding to the cis-acting element of leuO. However, our footprinting analyses suggests that the binding of H-NS is relatively weaker than LeuO or ToxR at the same molarity. Considering that the DNA nucleotide sequences of the upstream regions of leuO genes are highly conserved among various Vibrio, such patterns as those found in V. vulnificus would be a common feature in the regulation of leuO gene expression in Vibrionaceae. Taken together, these results suggest that, in species belonging to Vibrionaceae, H-NS regulates the expression of leuO as a basal stopper when cFP-ToxR mediated signaling is absent.

• Structural Engineering and Mechanics
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• 제45권1호
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• pp.1-18
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• 2013

The typhoon wind characteristics designing for buildings or bridges located in complex terrain and typhoon prone region normally cannot be achieved by the very often few field measurement data, or by physical simulation in wind tunnel. This study proposes a numerical simulation procedure for predicting directional typhoon design wind speeds and profiles for sites over complex terrain by integrating typhoon wind field model, Monte Carlo simulation technique, CFD simulation and artificial neural networks (ANN). The site of Stonecutters Bridge in Hong Kong is chosen as a case study to examine the feasibility of the proposed numerical simulation procedure. Directional typhoon wind fields on the upstream of complex terrain are first generated by using typhoon wind field model together with Monte Carlo simulation method. Then, ANN for predicting directional typhoon wind field at the site are trained using representative directional typhoon wind fields for upstream and these at the site obtained from CFD simulation. Finally, based on the trained ANN model, thousands of directional typhoon wind fields for the site can be generated, and the directional design wind speeds by using extreme wind speed analysis and the directional averaged mean wind profiles can be produced for the site. The case study demonstrated that the proposed procedure is feasible and applicable, and that the effects of complex terrain on design typhoon wind speeds and wind profiles are significant.

• 한국양식학회지
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• 제12권4호
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• pp.323-331
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• 1999

Most of channel fish farming in Alabama are still earthen pond style, and filled by rainfall and runoff. The water levels of ponds are maintained with stand-pipe, and the effluent from ponds very little discharged at usual time except ant heavy rains and crop season. Overflow from ponds following rains occurs mostly in winter and early spring when stream flows high. In this study to know how much effluents fish ponds affected to streams which are nearby ponds, a survey carried out on the variation of water quality of seven streams and effluents at heavy rains. Water samples were collected at 14 sites on upstream (did not affected by effluents) and downstream(being affect by effluents), and sampled monthly from August 1997 to August 1998. There were no clear trends of difference in most water quality variables between upstream and downstream of catfish farms during a year. The effluents from ponds after heavy rains were not highly polluted, but sometimes have elevated concentrations of TSS. Nitrogen content of effluents was higher than that of routine streams , but phosphorus was not clear. From this result suggest than the effluents from catfish farm are not having adverse impacts on stream water quality still yet .

• 한국통신학회논문지
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• 제28권7B호
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• pp.620-627
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• 2003

EPON망은 중앙 기지국과 가입자들 사이에 광 액세스 라인을 저렴하게 제공할 수 있는 액세스 망 기술로 떠오르고 있다. 동적 대역 할당은 상향 채널의 효율적인 활용을 위해 ONU간 통계적 다중화를 제공한다. 본 논문에서는 EPON망에서 차등 CoS를 제공하기 위해 주기적 폴링을 기반으로 한 동적 대역 할당 방법을 제안한다. 더불어, Interleaved 폴링 방식에 기반한 동적 대역 할당 방안은 상향 트래픽 로드가 적은 경우 하향 채널의 용량을 대폭 감소시키는 단점을 가지고 있음을 보인다. 실제적인 시뮬레이션 결과를 얻기 위해 self-similarity와 long-range dependence 특성을 갖는 트래픽을 이용하였다. EPON망의 성능은 ONU에 제공되는 다양한 로드별로 분석하였으며, 특히 차등 CoS 특성 분석을 위해 등급별 패킷의 지연 특성을 분석하였다.

• 생명과학회지
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• 제22권10호
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• pp.1286-1294
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• 2012

섬진강에서 2009년과 2010년 사이의 대형무척추동물에 대한 생물학적 군락 분석을 실시하였다. 조사 정점에 재해 총 10목 24과 106종이 채집이 되었다. 비록 정점별 종과 개체수는 다르지만 조사 시기별로는 정점 간 유의한 차이를 나타내지 않았다. 정점별 우점종은 달랐다. 2009년 5월 정점에 대해 정점 1이 5종인 반면 정점 2는 66종으로 차이를 보였으며 평균 종수는 38.3종이었다. 반면에 정점 2는 2009년 11월에 가장 많은 종수를 나타내었고 정점 3은 가장 낮았다. 대형무척추동물 중에서 절지동물문(Phylum Arthropod)이 종 수준 또는 개체 수준에서 우점이었는데 종 수준으로 5월은 63.2%, 11월은 60.9%였다. 조사 정점에 대한 환경 인자 분석의 결과 대형무척추 동물의 서식에 미치는 인자로 용존산소량(DO), 생물학적 산소요구량(BOD), 화학적 산소요구량(COD)이 중요한 것으로 나타났다. 생물학적 종다양도는 섬진강 상류에서 하류로 갈수록 낮아지는 경향을 나타내었다.

• 한국물환경학회지
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• 제21권4호
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• pp.368-378
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• 2005

Inorganic matters originated from stone quarries and manufacturing plants could alter the ecological characteristics of adjacent aquatic systems, especially the structure and function of benthic macroinvertebrate community. In such situation, the locality of stone quarry and the quantity of inorganic matters would be important factors that determined the disturbing strength to the benthic macroinvertebrate community. Locality patterns of stone quarries were classified into 3 types in relation to the stream ecosystem; stream-proximity, upstream-inclusion and tributary-inclusion type. In the result of species:abundance analysis, stone quarry B (upstream-inclusion type) showed geometric distribution, while others showed broken-stick distribution pattern. The benthic macroinvertebrate communities closer to stone quarries showed smaller species numbers and standing crops among all types of stone quarries. However the values of species evenness index were not seriously different between controls and directly affected sites. These results indicated that the effect of inorganic disturbance would differ from those of organic pollution that induced the highly dominant state occupied by tolerant species. Number of occurred species, standing crops, community indices and biotic indices indicated that the community of upstream-inclusion type was the most seriously damaged from the inorganic disturbance, and the community would be very simple and unstable. Tributary-inclusion stone quarry heavily damaged to tributary system in biologically, but influence to the main stream seemed to be depended on the scale of main stream. Among 3 types of stone quarry localities, stream-proximity type induced the least damages to benthic macroinvertebrate community, though the degrees of damage were different along with distances between stream and stone quarry.

• 대한의생명과학회지
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• 제13권3호
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• pp.239-244
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• 2007

Hoxc8 is one of the homeotic developmental control genes regulating the expression of many downstream target genes, through which animal body pattern is established during embryonic development. In previous proteomics analysis, proliferating cell nuclear antigen (PCNA) which is also known as cyclin, has been implied to be regulated by Hoxc8 in F9 murine embryonic teratocarcinoma cell. When the 5' upstream region of PCNA was analyzed, it turned out to contain 20 Hox core binding sites (ATTA) in about 1.17 kbp (kilo base pairs) region ($-520{\sim}-1690$). In order to test whether this region is responsible for Hoxc8 regulation, the upstream 2.3 kbp fragment of PCNA was amplified through PCR and then cloned into the pGL3 basic vector containing a luciferase gene as a reporter. When the luciferase activity was measured in the presence of effector plasmid (pcDNA : c8) expressing murine Hoxc8, the PCNA promoter driven reporter activity was reduced. To confirm whether this reduction is due to the Hoxc8 protein, the siRNA against Hoxc8 (5'-GUA UCA GAC CUU GGA ACU A-3' and 5'-UAG UUC CAA GGU CUG AUA C-3') was prepared. Interestingly enough, siRNA treatment up regulated the luciferase activity which was down regulated by Hoxc8, indicating that Hoxc8 indeed regulates the expression of PCNA, in particular, down regulation in NIN3T3 cells. These results altogether indicate that Hoxc8 might orchestrate the pattern formation by regulating PCNA which is one of the important proteins involved in several processes such as DNA replication and methylation, chromatin remodeling, cell cycle regulation, differentiation, as well as programmed cell death.