• Title/Summary/Keyword: exposed region

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Regional Structure and Locational Characteristics of Najin-Seonbong Economic and Trade Zone (나진-선봉 경제 무역 지대의 입지특성과 지역구조)

  • Lee, Ki-Suk;Lee, Ock-Hee;Choe, Han-Sung;Ahn, Jae-Seob;Nan, Ying
    • Journal of the Korean Geographical Society
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    • v.37 no.4
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    • pp.293-316
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    • 2002
  • This study aims to identify changes that have occurred in the regional structure and locational characteristics of the Najin-Seonbong Economic and Trade Zone established in North Korea in 1991. In order to analyze land use patterns as variables of change in the regional structure, an field trip data, satellite imagery and other materials about the region are examined. In terms of its location as a major regional transit hub, the Najin-seonbong Economic and Trade Zone has not been supported by the required infrastructural developments and the establishment of the export processing zones has exposed the lack of vital links with local networks and industry. Thus, despite the fact that the local government has made a lot of effort in attracting foreign investment over the past decade, little progress has been made and the region has not changed. By and large, its operational efficiency and potential for development as a major export processing zone has been relatively limited. In the long w, prospects for the region's emergence as a major economic player will depend on the North Korean Govemment's policy in tackling the various infrastructural deficiencies.

Characteristics of Persistent of Hexachlorocyclohexane(HCH) in Ambient Air-Soil-Water-Sediment for a Emerging Persistent Organic Pollutants(POPs) (신규 잔류성 유기오염물질(Emerging Persistent Organic Pollutants E-POPs) 핵사클로로시클로핵산(HCH)의 대기-토양-물-저질에서의 잔류특성)

  • Hwang, Sung-Min;Lee, Seok-Hyung;Park, No-Jin;Ok, Gon
    • Journal of Environmental Science International
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    • v.19 no.12
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    • pp.1343-1354
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    • 2010
  • The purpose of the study was to analyze the persistence of HCH in atmosphere, soil, sediment and water of the western and southern regions of Korea. The samples from the western region were collected from Anmyeon Island, and the samples from the southern region were collected from Kimhae and Busan. The concentration of HCH isomers in atmosphere showed the pattern of $\alpha$-HCH>$\gamma$-HCH>$\beta$-HCH. The regions with high HCH concentration in the atmosphere are the regions that have been highly exposed to HCH used in the past, and the areas that have been influenced by the long range transport. The HCH that persists in the soil, water and sediment evaporates into the atmosphere, showing the characteristics of Air-Surface exchange. When the regional concentration distributions are compared, the concentration of HCH was higher in the atmosphere of a plain and the cities near the plain, than the urban areas. In this study, the ratio of $\alpha/\beta$-HCH was used as an indicator for estimating the source of Technical HCH and Lindane. According to the result, the contribution of Lindane was high in Kimhae plain and Kimhae urban areas. However, in Busan, the contribution of Technical HCH was higher than Lindane. In case of Anmyeon Island, the western region of Korea had high contribution from Tehcnical HCH. In soil and sediment, $\beta$-HCH was dominant. In water, $\gamma$-HCH was dominant among other isomers. Such results are due to $\gamma$-HCH inLindane. Furthermore, the source of $\gamma$-HCH in urban areas is assumed to be the use of medicine, medical supplies and other living supplies. Based on the results of this study, the management of HCH, a newly list up emerging POPs, should be strengthened by further research on sources, fate, persistency, accumulation and exposures and etc. to the risk assessments.

Recent Advancement on the Knowledges of Meiotic Division (I) (減數分裂, 最近의 進步(I))

  • 한창열
    • Korean Journal of Plant Tissue Culture
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    • v.25 no.6
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    • pp.453-475
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    • 1998
  • During the 100 years since the initial discovery of meiotic phenomenon many brilliant aspects have been elucidated, but further researches based on light microscopy alone as an experimental tool have been found to have some limits and shortcomings. By the use of electron microscopy and armed with the advanced knowledges on modern genetics and biochemistry it has been possible to applu molecular technology in gaining information on the detailed aspects of meiosis. As synapsis takes place, a three-layered proteinous structure called the synatonemal complex starts to form in the space between the homologous chromosomes. To be more precise, it begins to form along the paired chromosomes early in the prophase I of meiotic division. The mechanism that leads to precise point-by-point pairing between homologous chromocomes division. The mechamism that leads to precise point-by-point pairing between homologous chromosomes remains to be ascertained. Several items of information, however, suggest that chromsome alignment leading to synapsis may be mediated somehow by the nuclear membrane. Pachytene bivalents in eukaryotes are firmly attached to the inner niclear membrane at both termini. This attached begins with unpaired leptotene chromosomes that already have developed a lateral element. Once attached, the loptotene chromosomes begin to synapse. A number of different models have been proposed to account for genetic recombination via exchange between DNA strands following their breakage and subsequent reunion in new arrangement. One of the models accounting for molecular recombination leading to chromatid exchange and chiasma formation was first proposed in 1964 by Holliday, and 30 years later still a modified version of his model is favored. Nicks are made by endomuclease at corresponding sites on one strant of each DNA duplex in nonsister chromatid of a bivalent during prophase 1 of meiosis. The nicked strands loop-out and two strands reassociate into an exchanged arrangement, which is sealed by ligase. The remaining intact strand of each duplex is nicked at a site opposite the cross-over, and the exposed ends are digested by exonuclease action. Considerable progress has been made in recent years in the effort to define the molecular and organization features of the centromere region in the yeast chromosome. Centromere core region of the DNA duplex is flanked by 15 densely packed nucleosomes on ons side and by 3 packed nucleosomes on the other side, that is, 2000 bp on one side and 400 400 bp in the other side. All the telomeres of a given species share a common DNA sequence. Two ends of each chromosome are virtually identical. At the end of each chromosome there exist two kinds of DNA sequence" simple telpmeric sequences and telpmere-associated sequencies. Various studies of telomere replication, function, and behabior are now in progress, all greatly aided by molecular methods. During nuclear division in mitosis as well as in meiosis, the nucleili disappear by the time of metaphase and reappear during nuclear reorganizations in telophase. When telophase begins, small nucleoli form at the NOR of each nucleolar-organizing chromosome, enlarge, and fuse to form one or more large nucleoli. Nucleolus is a special structure attached top a specific nucleolar-organizing region located at a specific site of a particular chromosome. The nucleolus is a vertical factory for the synthesis of rRNAs and the assenbly of ribosome subunit precursors.sors.

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Estimation of Spectral Distribution of Illumination Using Maximum Achromatic Region (최대 무채색 영역을 이용한 광원의 분광분포 추정)

  • Kim, Hui-Su;Kim, Yun-Tae;Lee, Cheol-Hui;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.4
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    • pp.392-400
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    • 2001
  • This paper proposes an illuminant estimation algorithm that estimates the spectral power distribution of an incident light source from a single image. The proposed illumination recovery procedure has two phases. First, the surface spectral reflectances are recovered in the maximum achromatic region (MAR) which is the most achromatic and highly bright region of an image after removing partially the effect of illumination using a modified gray world algorithm. Here, the surface reflectances of MAR are estimated using the principal component analysis method along with a set of given 1269 Munsell samples. Second, the Population of reflected lights is determined with 1269 Munsell samples and a set of illuminations then the spectral distribution of re(looted lights of MAR is selected from the spectral database. That is, color differences are compared between the reflected lights of the MAR and the spectral database, which is the set of reflected lights built by the given set of Munsell samples and illuminants. Then the closest colors from the spectral database are selected. Finally, the illuminant of an image can be calculated dividing the average spectral distributions of reflected lights of MAR by the average surface reflectances of the MAR. In order to evaluate the proposed algorithm, experiments with artificial scenes, which are exposed to chromatic illuminants, were performed and the spectral distribution of estimated illumination and color difference are compared with results of the conventional method.

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Influence of Couch and Collimator on Dose Distribution of RapidArc Treatment Planning for Prostate Cancer in Radiation Therapy (치료테이블과 콜리메이터가 전립선암 래피드아크 치료계획의 선량분포에 미치는 영향)

  • Kim, Hyung-Dong;Kim, Byung-Young;Kim, Sung-Jin;Yun, Sang-Mo;Kim, Sung-Kyu
    • Progress in Medical Physics
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    • v.23 no.2
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    • pp.99-105
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    • 2012
  • We investigated the influence of photon energy, couch and collimator angle differences between arcs on dose distribution of RapidArc treatment planning for prostate cancer. RapidArc plans were created for 6 MV and 10 MV photons using 2 arcs coplanar and noncoplanar fields. The collimator angle differences between two arcs were $0^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$ and $90^{\circ}$. The plans were optimized using same dose constrains for target and OAR (organ at risk). To evaluate the dose distribution, plans were analyzed using CI (conformity index), HI (homogeneity index), QOC (quality of coverage), etc. Photon energy, couch and collimator angle differences between arcs had a little influence on the target and OAR. The difference of dosimetric indices was less than 3.6% in the target and OAR. However, there was significant increase in the region exposed to low dose. The increase of V15% in the femur was 6.4% (left) and 5.5% (right) for the 6 MV treatment plan and 23.4% (left), 24.1% (right) for the noncoplanar plan. The increase of V10% in the Far Region distant from target was 54.2 cc for the 6 MV photon energy, 343.4 cc for the noncoplanar and 457.8 cc for the no collimator rotation between arcs.

A Study on Current Status and Management of Protected Trees in Gangwon-Province (강원도 보호수의 현황과 관리 실태에 관한 연구)

  • Kim, Hea-Ran;Kim, Dong-Yeob;Park, Jun-Seok;Lee, Ki-Eui;Park, Won-Jei
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.1
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    • pp.12-26
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    • 2010
  • This study was conducted to investigate current states and management of the protected trees in Gangwon-do. There were 701 protected trees in 42 species designated by 2008, which were distributed at 425 places. Major species were Zelkova serrata(29%), Pinus densiflora(24%), Ulmus davidiana var. japonica(11%), and Ginkgo biloba(5%). The protected trees played various roles in the villages, mostly as sacred trees(43%). The 51% of protected trees were 300 years or more in age, the 53% were more than 20 m in height, and the 57% were more than 300 cm in girth at breast height. The 69% of the protected trees have been designated for protection in 1982 and the rest have been designated by the local cities by 2008. The species number of the protected trees in Youngseo region was greater than that of the Youngdong region. The major species were Zelkova serrata (33%) and Pinus densiflora(17%) in Youngseo region, and were Pinus densiflora (38%) and Zelkova serrata(19%) in Youngdong region. The ratio of native species to exotic species was 33:1 in Youngseo region, and were 25:6 in Youngdong region. The 29% of protected trees were located in the field, 28% in the mountain, and 25% in the villages. The 45% of the ground were covered by herbaceous plants, 39% exposed, and 10% gravel mulch. Most of the protected trees had good growing conditions. The 70% of the protected trees were under good maintenance, and the rest were under undesirable conditions. The soil characteristics of the protected tree areas in Gangwon-do were not much different from those of Korean average. It seemed to be necessary to increase designation of protected trees based on the tradition, history, local value and academic application in Gangwon-do. In addition, it is desirable to suggest plans to utilize and manage protected tree areas for enhancing the value of natural heritages in Gangwon-do.

Consideration Regarding the Breast Cancer Treatment Plan That Used Irregular Surface Compensator (ISC) (Irregular Surface Compensator (ISC)를 이용한 유방암치료계획에 관한 고찰)

  • Je, Young-Wan;Kim, Chan-Yong;Park, Heung-Deuk
    • The Journal of Korean Society for Radiation Therapy
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    • v.19 no.2
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    • pp.131-141
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    • 2007
  • Purpose: Try to compare dose distribution and lung dose of radiation treatment plan of the breast cancer that used Irregular Surface Compensator (ISC) and treatment plan that used a wedge filter. Materials and Methods: Established a treatment plan to be distributed over 95% of prescription dose (5,040 cGy) of the two tangent-half fields that used a wedge filter and ISC at a breast organization as made to breast cancer patient having an irregular surfaces after surgery. Compared high dose area and DVH, and verified a treatment plan as used film with rectangular phantom. Results: Maximum dose point in breast tissue appeared to 107.5% in case of tangent-half fields Tx plan that used a wedge filter, and lung volumes exposed above 20 Gy by 7.63%. In case of ISC, maximum dose point in breast tissue appeared to 106.4%, and lung volumes exposed above 20 Gy by 6.5%. The film measurement results that used phantom, 105$\sim$110% high dose region was distributed to the upper part and both edges of phantom. However in case of ISC, appeared by 100$\sim$105% dose conformity distribution. Conclusion: In general, the Irregular Surface Compensator (ISC) can improve the dose conformity of breast tissues, as well as reduced hot spots in the lung and in the breast. Such an advantage by using ISC technique is more beneficial for patients who have more irregular surfaces after surgery.

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Repression of Cathepsin D Expression in Adipocytes by MicroRNA-145 (지방세포에서 microRNA-145에 의한 Cathepsin D의 발현 제어)

  • Kim, Hyun-Ji;Bae, In-Seon;Seo, Kang-Seok;Kim, Sang Hoon
    • Journal of Life Science
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    • v.24 no.7
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    • pp.798-803
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    • 2014
  • Cathepsin D (CtsD), an aspartyl peptidase, is involved in apoptosis, resulting in the release of cytochrome C from mitochondria in cells. Here, we investigated microRNA regulation of CtsD expression in 3T3-L1 cells First, we observed the expression of CtsD in cells in response to doxorubicin (Dox). As expected, the level of CtsD mRNA was increased in 3T3-L1 cells exposed to Dox in a dose-dependent manner. Cellular viability of ectopically expressed CtsD cells was also decreased. Next, we used the miRanda program to search for particular microRNA targeting CtsD. MiR-145 was selected as a putative controller for CtsD because miR-145 had a high mirSVR score. In a reporter assay, the luciferase activity of cells containing the CtsD 3'-UTR region was decreased in cells transfected with miR-145 mimic compared to that of a control. The level of CtsD expression was down-regulated in preadipocytes ectopically expressing miR-145 and up-regulated by an miR-145 inhibitor. Cells also suppressed miR-145 expression when exposed to Dox. The miR-145 inhibitor reduced the cellular viability of 3T3-L1 cells. Taken together, these data suggest that miR-145 regulates CtsD-mediated cell death in adipocytes. These findings may have valuable implications concerning the molecular mechanism of CtsD-mediated cell death in obesity, suggesting that CtaD could be a useful therapeutic tool for the prevention and treatment of obesity by regulating fat cell numbers.

Effects of Zizyphi Spinosae Extract on Cisplatin and t-Butylhydroperoxide Induced Acute Renal Failure in Rabbits (토끼에서 cisplatin에 의해 유도된 급성 신부전시 산조인 추출물의 효과)

  • Kim, Jae Young;Kim, Chung Hui
    • Journal of Life Science
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    • v.24 no.7
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    • pp.777-783
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    • 2014
  • Cathepsin D (CtsD), an aspartyl peptidase, is involved in apoptosis, resulting in the release of cytochrome C from mitochondria in cells. Here, we investigated microRNA regulation of CtsD expression in 3T3-L1 cells. First, we observed the expression of CtsD in cells in response to doxorubicin (Dox). As expected, the level of CtsD mRNA increased in 3T3-L1 cells exposed to Dox in a dose-dependent manner. The cellular viability of ectopically expressed CtsD cells was decreased. Next, we used the miRanda program to search for particular microRNA targeting CtsD. MiR-145 was selected as a putative controller of CtsD because it had a high mirSVR score. In a reporter assay, the luciferase activity of cells containing the CtsD 3'-UTR region decreased in cells transfected with a miR-145 mimic compared to that of a control. The level of CtsD expression was down-regulated in preadipocytes ectopically expressing miR-145 and up-regulated by an miR-145 inhibitor. Cells also suppressed miR-145 expression when exposed to Dox. The miR-145 inhibitor reduced the cellular viability of 3T3-L1 cells. Taken together, these data suggest that miR-145 regulates CtsD-mediated cell death in adipocytes. These findings may have valuable implications concerning the molecular mechanism of CtsD-mediated cell death in obesity, suggesting that CtsD could be a useful therapeutic tool for the prevention and treatment of obesity by regulating fat cell numbers.

Chemical weathering in King George Island, Antarctica

  • Jeong, Gi-Young
    • Proceedings of the Mineralogical Society of Korea Conference
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    • 2003.05a
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    • pp.66-66
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    • 2003
  • King George island, Antarctica, is mostly covered by ice sheet and glaciers, but the land area is focally exposed for several thousand years after deglaciation. For a mineralogical study of chemical weathering in the polar environment, glacial debris was sampled at the well-developed patterned ground which was formed by long periglaclal process. As fresh equivalents, recently exposed tills were sampled at the base of ice cliff of outlet glaciers and at the melting margin of ice cap together with fresh bedrock samples. Fresh tills are mostly composed of quartz, plagioclase, chlorite, and illite, but those derived from hydrothermal alteration zone contain smectite and illite-smectite. In bedrocks, chlorite was the major clay minerals in most samples with minor illite near hydrothermal alteration zone and interstratified chlorite-smectite in some samples. Smectite closely associated with eolian volcanic glass was assigned to alteration in their source region. Blocks with rough surface due to chemical disintegration showed weathering rinds of several millimeter thick. Comparision between inner fresh and outer altered zones did not show notable change in clay mineralogy except dissolution of calcite and some plagioclase. Most significant weathering was observed in the biotite flakes, eolian volcanic glass, sulfides, and carbonates in the debris. Biotite flakes derived from granodiorite were altered to hydrobiotite and vermiculite of yellow brown color. Minor epitactic kaolinite and gibbsite were formed in the cleaved flakes of weathered biotite. Pyrite was replaced by iron oxides. Calcite was congruently dissolved. Volcanic glass of basaltic andesite composition showed alteration rim of several micrometer thick or completely dissolved leaving mesh of plagioclase laths. In the alteration rim, Si, Na, Mg, and Ca were depleted, whereas Al, Ti, and Fe were relatively enriched. Mineralization of lichen and moss debris is of much interest. They are rich of A3 and Si roughly in the ratio of 2:1 to 3:1 typical of allophane. In some case, Fe and Ti are enriched in addition to Al and Si. Transmission electron microscopy of the samples rich of volcanic glass showed abundant amorphous aluminosilicates, which are interpreted as allophane. Chemical weathering in the King George Island is dominated by the leaching of primary phyllosilicates, carbonates, eolian volcanic glass, and minor sulfides. Authigenesls of clay minerals is less active. Absence of a positive evidence of significant authigenic smectite formation suggests that its contribution to the clay mineralogy of marine sediments are doubtful even near the maritime Antarctica undergoing a more rapid and intenser chemical weathering under more humid and milder climate.

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