• 제목/요약/키워드: Early region

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베인 선단부의 탄성유체윤활 (Elastohydrodynamic Lubrication on the Vane Tip of Vane Pump)

  • 정석훈;정재연
    • Tribology and Lubricants
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    • 제10권3호
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    • pp.54-61
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    • 1994
  • The regimes of elastohydrodynamic lubrication at the points where line contacts occur between the vane tip and camring in an oil hydraulic vane pump is studied. A study of the contact conditions in vane pump provided most of the early interest in the possibility of fluid film lubrication in highly loaded contacts. The variation of viscosity with pressure and the elastic deformation associated with the high pressures generated in the contact region are the major causes of the complexity attributed to lubrication behavior. Therefore a numerical solutions to the problem of elastohydrodynamic lubrication of line contact are obtained by using a finite-difference formulation.

HOT GAS IN ELLIPTICAL GALAXIES

  • Kim, Dong-Woo
    • 천문학논총
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    • 제8권1호
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    • pp.199-206
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    • 1993
  • We review recent systematic investigation of the X-ray spectra of early type galaxies by using the Einstein data base and present new results by the ROSAT observations. The Einstein data suggested that the galaxies with low X-ray to optical luminosity ratio may have another very soft component. ROSAT observations confirm its presence and call for further study to understand the nature of this very soft emission. The X-ray bright galaxies have emission temperature of ${\sim}\;0.8\;keV$ and show radial gradients in the sense that X-ray emission is softer and more absorbed in the inner region.

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Ganglioglioma in Brainstem : Case Report and a Review of Literatures

  • Kim, Sung-Duk;Kim, Jong Hyun;Lee, Cheol-Young;Kim, Hyun-Woo
    • Journal of Korean Neurosurgical Society
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    • 제55권3호
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    • pp.164-166
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    • 2014
  • Ganglioglioma is an infrequent tumor of the central nervous system (CNS); mostly supratentorial region. But, they can occur anywhere in the central nervous system such as brainstem, cerebellopontine angle (CPA), thalamus, optic nerve and spinal cord. Although it occurs rarely, ganglioglioma should be included in the differential diagnosis of a posterior fossa mass because early recognition is important for treatment and patient counseling.

Evaluation of Microcanonical Rate Constants by Semiclassical Boundary Conditions : Early Asymptotic Analysis

  • Sungyul Lee
    • Bulletin of the Korean Chemical Society
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    • 제13권5호
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    • pp.538-541
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    • 1992
  • An approximate scheme for evaluating total reaction probability is proposed. Semiclassical boundary conditions are imposed well before the asymptotic region in the reactant and product channels to calculate the Green's function and its derivatives. Propagations are confined to a limited regime near the activated complex. Calculations are made for one dimensional Eckart barrier model of H + $H_2$ reaction. Implications of the procedure in multi-dimensional systems are discussed.

Clubroot Affects Both Agriculture and Tourism in Kagoshima Prefecture, Japan

  • Higuchi, Koichi;Tanaka, Yoshihiro;Matsumoto, Satoru;Omatsu, Naoshi;Inoue, Hideaki
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2015년도 춘계학술대회 및 임시총회
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    • pp.50-50
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    • 2015
  • Both agriculture and local tourism of Kagoshima prefecture where is located on the south-western region of the Japanese mainland, are the important industries. Although cabbage (Brassica oleracea) has been cultivated in recent decades in Kagoshima, clubroot disease caused by Plasmodiophora brassicae had never been observed. However, the disease in cabbage was reported in four regions last couple years. Our survey showed that one region is infested severely whereas others are slightly. In the most widely infested region, the disease was also observed in turnip rape (Brassica rapa) which is grown as ornamental plants for landscape design in early spring and important tourist attraction. Consequently, both agriculture and local tourism are damaged by clubroot. The increase of clubroot incidence in this region might be caused by significant increase of cabbage production, the expansion of cropping season throughout the year and continuous turnip rape cultivation in the same fields of cabbage for almost three decades. Therefore we are trying to estimate the risk of clubroot damage cultivation throughout the year in this region. We collected five isolates of resting spores and identified them as race 3, 4 and 9 by Williams' method, and as pathotype group 3 and 4 by classification system using clubroot resistant (CR) $F_1$ cultivars of Chinese cabbage as differential hosts as described in Hatakeyama et al.(2004). Furthermore, we found that these populations were avirulent to commercial CR cabbages. These results indicate that introduction of CR cabbage and breeding of turnip rape are the effective measures to solve our problem.

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지역 및 파종기 차이가 소맥의 등숙 및 품질에 미치는 영향 (Effects of Region and Sowing Date on Grain- filling and Quality in Wheat)

  • 류용환;하용웅;최창열
    • 한국작물학회지
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    • 제28권3호
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    • pp.368-373
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    • 1983
  • 본 시험은 1978년부터 1979년까지 2개년간 수원과 광주에서 소맥 “조광”을 공시하여 파종기를 달리하였을 때 등숙기간중 립중의 경시적인 증가양상과 품질의 변이에 관하여 등숙기간별로 추적조사한 바 그 결과를 요약하면 다음과 같다. 1. 출수기는 지역간에는 수원에서 파종기차이에서는 적기파종에서 빨랐으나 년차간에는 차이가 없었으며 출수까지의 일수는 지역 및 파종기에 따라 변이가 비교적 커서 수원에서 225-207일, 광주는 192-176일이 소요되었다. 2. 등숙전기의 립중은 광주에서 보다 수원에서 무거웠으나 최종 립중은 반대로 광주에서 높았다. 3. 등숙일수는 년차변이가 커서 수원에서 적기파종한 경우는 43-49일, 광주는 44-51일이었으며 만기파종은 동일지역내에서 적기파종에 비해 1-4일이 단축되었다. 4. 제분율은 지역간에는 광주에서, 파종기간에는 적기파종에서 다소 높았으며 등숙일수에 따라서는 등숙이 진전됨에 의해 증가하여 만기파종에서는 출수후 45일에 최대가 되었으나 적기파종에서는 45일이후까지 경미한 증가경향을 보였다. 5. 단백질함량과 심전가는 제분율과는 반대로 고온하에서 등숙이 이루어진 북부지방에서, 파종기에 따라서는 만기파종에서 높았으며 등숙기간별로는 일양적인 경향이 없었다.

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Transcriptional Activator Elements for Curtovirus C1 Expression Reside in the 3' Coding Region of ORF C1

  • Hur, Jingyung;Buckley, Kenneth J.;Lee, Sukchan;Davis, Keith R.
    • Molecules and Cells
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    • 제23권1호
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    • pp.80-87
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    • 2007
  • Beet curly top virus (BCTV) and Beet severe curly top virus (BSCTV), members of curtoviruses, encode seven open reading frames (ORFs) within a ~3 kb genome. One of these viral ORFs, C1, is known to play an important role in the early stage of viral infection in plants during initiation of viral DNA replication. We used promoter:: reporter (${\beta}$-glucuronidase) gene fusions in transgenic Arabidopsis to identify the putative promoter region of BCTV ORF C1. Unlike other geminiviruses, the intergenic region of BCTV was not sufficient to promote C1 expression in transgenic plants. When sequences extending into the coding region of C1 were tested, strong expression of the reporter protein was observed in vascular tissues of transgenic plants. This expression was not dependent on the presence of the intergenic regions or proximal 5' portions of the C1 coding region. Transgenic plants expressing a reporter gene under control of the putative complete C1 promoter were inoculated with virus to determine if any viral transcript affected C1 expression. Virus inoculated plants did not show any altered pattern or change in of reporter gene expression level. These results suggest that (1) important transcriptional activator elements for C1 expression reside in the 3' portion of C1 coding area itself, (2) C1 protein does not auto-regulate its own expression and (3) C1 expression of two curtoviruses is controlled differently compared to other geminiviruses.

Identification of the Regulatory Region Responsible for Vascular Tissue-Specific Expression in the Rice Hd3a Promoter

  • Pasriga, Richa;Cho, Lae-Hyeon;Yoon, Jinmi;An, Gynheung
    • Molecules and Cells
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    • 제41권4호
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    • pp.342-350
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    • 2018
  • Flowering time is determined by florigens. These genes include, Heading date 3a (Hd3a) and Rice FT 1 (RFT1) in rice, which are specifically expressed in the vascular tissues of leaves at the floral transition stage. To study the cis-regulatory elements present in the promoter region of Hd3a, we generated transgenic plants carrying the 1.75-kb promoter fragment of Hd3a that was fused to the ${\beta}$-glucuronidase (GUS) reporter gene. Plants expressing this construct conferred a vascular cell-specific expression pattern for the reporter gene. However, GUS was expressed in leaves at all developmental stages, including the early seedling stage when Hd3a was not detected. Furthermore, the reporter was expressed in roots at all stages. This suggests that the 1.75-kb region lackings cis-elements that regulate leaf-specific expression at the appropriate developmental stages. Deletion analyses of the promoter region indicated that regulatory elements determining vascular cell-specific expression are present in the 200-bp region between -245 bp and -45 bp from the transcription initiation site. By transforming the Hd3a-GUS construct to rice cultivar 'Taichung 65' which is defective in Ehd1, we observed that Ehd1 is the major regulatory element that controls Hd3a promoter activity.

한국산 꿩의다리속(미나리아재비과)의 cpDNA trnL-F 지역의 분자진화와 유연관계: Indel events의 영향 (Molecular evolution of cpDNA trnL-F region in Korean Thalictrum L. (Ranunculaceae) and its phylogenetic relationships: Impacts of indel events)

  • 박성준;김혁진;박선주
    • 식물분류학회지
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    • 제42권1호
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    • pp.13-23
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    • 2012
  • trnL-F 지역은 엽록체 게놈 large single-copy 지역에 위치하며, trnL gene, trnL intron, trnL-F IGS로 구성된다. 본 연구는 한국산 꿩의다리속 내에서 trnL-F 지역의 분자진화와 유연관계를 분석하였다. 갭형질을 이용한 자료의 베이시안과 파시모니 분석에서 몇몇 indels evolution는 분계조를 지지하여 해상력이 좋은 계통수가 나타났다. 한국산 꿩의다리속 내에 cpDNA trnL-F 지역의 indel events는 계통학적으로 유용한 정보를 가지고 있는 것으로 판단된다. 산꿩의다리절(그늘꿩의다리 제외)은 속내에서 가장 먼저 분기한 것으로 나타났고, 나머지 절은 강하게 분계조를 형성하며 분기하였다. 한국산 꿩의다리속 내에 trnL-F 지역은 뉴클레오티드의 다양한 공간적 분포 변이와 주로 transversion에 따른 염기치환 등 다양한 진화적 패턴을 가지고 있었다.