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Studies on genus Pluteus of Korea (한국산 난버섯속에 관한 연구)

  • Lee, Ji-Na;Lee, Hee-Kyung;Min, Kyung-Hee;Park, Wan-Hee;Kim, Yang-Sup
    • The Korean Journal of Mycology
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    • v.20 no.4
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    • pp.296-301
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    • 1992
  • Species of genus Pluteus were cellected in Korea from 1984 to 1991. Eight species in Pluteus were identified, and six species were confirmed new to Korea and described here; Plutens atromarginatus, P. spinulosus, P. patricius, P. depauperatus, P. satur, and P. chrysophlebius ssp. sublaevigatus.

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Mechanical Properties of Rice Husk Flour-Wood Particleboard by Urea-Formaldehyde Resin

  • Lee, Young-Kyu;Kim, Sumin;Yang, Han-Seung;Kim, Hyun-Joong
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.3
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    • pp.42-49
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    • 2003
  • The objective of this research was to investigate the possibility of using rice husk flour as a partial substitute for the wood particles used as the raw material for manufacturing particleboards, by examining the physical and mechanical properties of the rice husk flour-wood particleboard as a function of the type of urea-formaldehyde resin used. Commercial wood particles and two types of rice husk flours (A type (30 ㎛), B type (300 ㎛)) were used. E1 and E2 class urea-formaldehyde resin was used as the composite binder, combined with 10 wt.% NH4Cl solution as a hardener. Rice husk flour-wood particleboards with dimensions of 27×27×0.7 (cm) were manufactured at a specific gravity of 0.7 with rice husk flour contents of 0, 5, 10, and 15 (wt.%). We examined the physical properties (specific gravity and moisture content), mechanical properties (three point bending strength and internal bonding) of the composite. In general, it can be concluded that composites made from rice husk flours are of somewhat poorer quality than those made from wood; however, blending in small amounts of rice husk flour (e.g., 5% to 10% by weight) may have no significant impact on quality.

Expression of Cyclin D3 Transcripts in the Postmeiotic Male Germ Cells of the Mouse

  • Sun, Woong-Sun;Geum, Dong-Ho;Choi, Wan-Sung;Kim Kwon, Yun-Hee;Rhee, Kun-Soo;Kim, Kyung-Jin
    • Animal cells and systems
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    • v.2 no.4
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    • pp.495-500
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    • 1998
  • D-type G1 cyclins are known to be crucial for the progression of mitotic cell cycle in mammals. Although many studies have been performed to elucidate the roles of D-type cyclins, it is largely unknown whether D-type cyclins are directly involved in the regulation of meiotic germ cell development. In the present study, we examined the expression patterns of D-type cyclins (cyclin D1 and D3) during male germ cell development by northern blot and in situ Hybridization analyses. In the adult testes, we detected a 4.2 kb cyclin D1 mRNA and two different sizes (2.3 kb and 1.8 kb) of cyclinD3 mRNAs. The short form of the cyclin D3 transcript was testis-specific. Along with the testicular development, expression of cyclin D3 mRNA was increased whereas cyclin D1 mRNA was gradually decreased. in situ hybridization study also revealed that the expression of cyclin D3 was restricted to the postmeiotic germ cells. Furthermore, the 2.3 kb transcript was highly expressed in the round spermatids and decreased in the elongated spermatids/residual bodies, while the 1.8 kb transcript was expressed in elongated spermatids/residual bodies more abundantly. Sucrose-gradient separation of polysomal RNA fractions demonstrated that some portions of the 2.3 kb transcript are translationally active, while the 1.8 kb transcript is likely to be inactive. Taken together, the present data suggest a functional importance of cyclin D3 expression in the differentiated postmeiotic male germ cells.

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Assessment on the Extraction Efficiency of Explosive Compounds in Soil for Improving the Working Draft of International Standard (국제표준(안) 개선을 위한 토양 중 화약물질 추출 효율성 평가)

  • Lee, Goon-Taek;Jung, In-Ho;Kim, Bo-Hyun;Kim, Dong-Wook
    • Journal of Soil and Groundwater Environment
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    • v.17 no.1
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    • pp.42-46
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    • 2012
  • The ISO document of ISO/TC/190/SC3/WG11/N11 is a working draft of international standard (WD) dealing with analytical method for the determination of explosives and related compounds using high performance liquid chromatography. The scope of this WD covers the storage of samples, preparing test portion, extraction and instrumentation. The main purpose of this study was to improve the extraction conditions which were already adopted in the WD. For this purpose, mechanical shaking method could be corresponded up to 18 hours of ultrasonic bath extraction in the WD was tested. Methanol was also tested with the intention of being added as an extracting solvent other than acetonitrile in the WD. According to the results, 16 hours of mechanical shaking method showed statistically the same effectiveness as that of 18 hours of ultrasonic bath extraction. In case of extracting solvent, methanol also showed statistically the same extraction capability as acetonitrile for DNB, TNT, 2-A-DNT and 2,4-DNT. However, the recovery rate of TNB with methanol extraction was 40% higher than that of acetonitrile extraction. Through adding mechanical shaking method into committee draft (cf. the next stage draft of the WD during the process for making international standard), ISO standard of analyzing explosives and related compounds in soil would become more useful in dealing with huge number of field samples in the laboratory. In other aspect, adopting methanol as an alternative extracting solvent would be very effective in the terms of exchangeability with GC-ECD/MS method which is being developed by German experts.

Korean plant proteomics: pioneers in plant stress physiology

  • Lee, Young-Woo;Bea, Suh-Yeon;Seo, Sang-Gyu;Shim, Ie-Sung;Kim, Sun-Hyung;Kim, Sang-Gon;Kang, Kyu-Young;Kim, Sun-Tae
    • Journal of Plant Biotechnology
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    • v.38 no.2
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    • pp.151-161
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    • 2011
  • Plant proteomics is the large-scale studies of proteins, particularly on their structures and functions, governed by the physiological metabolism of plant cells. With the development of techniques and strategies in proteomics, proteomics approach is moving forward in systems biology handling sophisticated components of major signaling and biochemical pathways in plants responding to their environment. In Korea, pioneers in plant proteomics are trying to catch up with global trends in plant proteomics; these researchers are not only improving existing techniques in protein extraction but also developing new techniques in proteomics context. In the hot field of abiotic and biotic stress proteomics, 29 and 9 out of 74 papers have been published during the review period from 2005 to 2010, respectively. This present review article provides an overview on the output of Korean plant proteomers while paying special attention to both abiotic and biotic stress proteomics.