• 제목/요약/키워드: Biological properties

검색결과 2,890건 처리시간 0.028초

Calculating Soil Quality Index for Biomass Production Based on Soil Chemical Properties

  • Kim, Sung-Chul;Hong, Young Kyu;Lee, Sang Phil;Oh, Seung Min;Lim, Kyung Jae;Yang, Jae E.
    • 한국토양비료학회지
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    • 제50권1호
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    • pp.56-64
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    • 2017
  • Soil quality has been regarded as an important factor for maintaining sustainability of ecosystem. Main purpose of this research was i) to select minimum factor for predicting biomass, and ii) to calculate soil quality index for biomass according to soil chemical properties. Result showed that soil pH, electrical conductivity (EC), soil organic matter (SOM), cation exchange capacity (CEC), and available phosphorus are minimum data set for calculating biomass production in soil. Selected representative soil chemical properties were evaluated for soil quality index and rated from 1 to 5 (1 is the best for biomass production). Percentage of each grade in terms of biomass production in national wide was 14.52, 35.23, 33.03, 6.47, 10.75% respectively. Although, only soil chemical properties were evaluated for calculating optimum soil quality, result of this research can be useful to understand basic protocol of soil quality assessment in national wide.

레이저 파장에서의 생체 침습적 및 비침습적 광학계수 측정 방법 (Invasive and non-invasive methods for estimating the optical properties of tissue at laser wavelengths)

  • 윤길원
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1994년도 추계학술대회
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    • pp.147-150
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    • 1994
  • To predict light propagation in biological tissues irradiated by laser, the optical properties such as absorption and scattering coefficients are required. There have been various techniques for measuring these coefficients. One method requires tissue samples, often a slab of thin tissue, is invasive. On the other hand, non-invasive method usually measures back-scattered light from a subject with no physical intervent ions. Advantages and disvantages of using different methods are investigated. A careful attention should be made in order to select the best method for a given experimental condition since, even either for invasive or non-invasive method, accuracy is subject to governing models and sample preparations.

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세포 증식 영상용 방사성의약품 (Radiopharmaceuticals for Imaging of Cellular Proliferation)

  • 오승준
    • 대한핵의학회지
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    • 제36권4호
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    • pp.209-223
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    • 2002
  • By considering the biological properties of a tumor, it should be possible to realize better results in cancer therapy. PET imaging offers the opportunity to measure tumor growth non-invasively and repeatedly as an early assessment of response to cancer therapy. Measuring cellular growth instead of energy metabolism showed offer significant advantages in evaluating therapy. Thymidine and its derivative nucleoside compounds can be changed to mono, di- and tri- phosphate compounds by thymidine kinase and then be incorporated into DNA. Their bindings are increased in highly proliferating cells due to the high DNA synthesis rate. To evaluate cell proliferation, many kinds of thymidine and uridine derivatives have been labeled with positron emitter and radioactive iodine. Compared to radiopharmaceuticals which have radioisotope labeled base ring such as pyirmidine, the radiopharmacuticals which have radioisotope labeled sugar ring are more stable in vivo and have metabolic resistance. The biological properties such as DNA incorporation ratios are highly dependent on their chemical structures and metabolic processes. This overview describes synthesis of radiopharmaceuticals and their biological properties for imaging of tumor cell proliferation.

목재 유물 김젖개의 몬테카를로 방법을 이용한 감마선 조사 (Optimal Gamma Irradiation Using Monte Carlo Simulations on Wooden Cultural Properties, Gimjeotgae)

  • 윤민철;최종일;이윤종;임길성;이주운
    • 방사선산업학회지
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    • 제6권1호
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    • pp.95-100
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    • 2012
  • In this study, there has been investigated the simulation of irradiation dose using Monte Carlo methodology for the biological control of wooden cultural property. In the evaluation of fungal contamination on wooden cultural properties, Cladosporium tenuissimum, Aspergillus versicolor, Penicillium sp. were mainly identified from the Gimjeotgae. But these microorganisms were completely inactivated by 20 kGy gamma-rays. For dosimetry simulation of wooden cultural properties, Monte Carlo methodology with MCNP was used. The radiation absorbed dose distribution was predicted at 8.2~18.9 kGy. These results show that irradiation is effective for biologic control of wooden cultural properties and Monte Carlo methodology is useful for non-destructive conservation and preservation of wooden cultural properties.

Stabilization of pitch-based carbon fibers accompanying electron beam irradiation and their mechanical properties

  • Park, Mi-Seon;Ko, Yoonyoung;Jung, Min-Jung;Lee, Young-Seak
    • Carbon letters
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    • 제16권2호
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    • pp.121-126
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    • 2015
  • Carbon fibers are prepared by stabilizing pitch fibers accompanying electron beam (E-beam) irradiation. The carbon fibers pretreated by E-beam irradiation achieve a higher stabilization index than the carbon fibers that are only heat-stabilized. In addition, the carbon fibers subjected to E-beam irradiation in the stabilization step exhibit a comparable tensile strength to that of general purpose carbon fibers. The carbon fibers pretreated with an absorbed dose of 3000 kGy have a tensile strength of 0.54 GPa for a similar fiber diameter. Elemental, Fourier-transform infrared spectroscopy, and thermogravimetric analyses indicate that E-beam irradiation is an efficient oxidation and dehydrogenation treatment for pitch fibers by showing that the intensity of the aliphatic C-H stretching and aromatic $CH_2$ bending (out-of-plane) bands significantly decrease and carbonyl and carboxylic groups form.

Characterization of Growth-supporting Factors Produced by Geobacillus toebii for the Commensal Thermophile Symbiobacterium toebii

  • Kim, Joong-Jae;Masui, Ryoji;Kuramitsu, Seiki;Seo, Jin-Ho;Kim, Kwang;Sung, Moon-Hee
    • Journal of Microbiology and Biotechnology
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    • 제18권3호
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    • pp.490-496
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    • 2008
  • Symbiobacterium toebii is a commensal symbiotic thermophile that cannot grow without support from a partner bacterium. We investigated the properties of Symbiobacterium growth-supporting factors (SGSFs) produced by the partner bacterium Geobacillus toebii. SGSFs occurred in both the cell-free extract (CFE) and culture supernatant of G. toebii and might comprise multifarious materials because of their different biological properties. The heavy SGSF contained in the cytosolic component exhibited heat- and proteinase-sensitive proteinaceous properties and had a molecular mass of >50 kDa. In contrast, the light SGSF contained in the extracellular component exhibited heat-stable, proteinase-resistant, nonprotein properties and had a molecular mass of <10 kDa. Under morphological examination using light microscopy, S. toebii cultured with the culture supernatant of G. toebii was filamentous, whereas S. toebii cultured with the CFE of G. toebii was rod-shaped. These results strongly suggest that the SGSFs produced by G. toebii comprise two or more types that differ in their growth-supporting mechanisms, although all support the growth of S. toebii. Upon the examination of the distribution of SGSFs in other bacteria, both cytosolic and extracellular components of Geobacillus kaustophilus, Escherichia coli, and Bacillus subtilis had detectable growth-supporting effects for S. toebii, indicating that common SGSF materials are widely present in various bacterial strains.