• 제목/요약/키워드: biological method

검색결과 5,044건 처리시간 0.051초

Effective Screening of Antagonist for the Biological Control of Soilborne Infectious Disease (Damping-Off)

  • LEE BAEK-SEOK;LEE HYANG-BOK;CHOI SUNG-WON;YUN HYUN-SHIK;KIM EUN-KI
    • Journal of Microbiology and Biotechnology
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    • 제15권4호
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    • pp.701-709
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    • 2005
  • An efficient method of selecting an antagonistic strain for use as a biological control agent strain was developed. In this improved method, the surface tension reduction potential of an isolate was included in the 'decision factor,' in addition to two other factors; the growth rate and pathogen inhibition. By using a statistically designed method, an isolate from the soil was selected and identified as Bacillus sp. GB 16. In the pot test, this strain showed the best performance among the isolated strains. The lowest disease incidence rate and fastest seed growth were observed when the Bacillus sp. GB 16 was used. The action of the surface tension reducing component was assumed to enhance the wetting, spreading, and residing of the antagonistic strain in the rhizosphere. This result showed that the improved selection method was quite effective in selecting the best antagonistic strain for the biological control of soilborne infectious plant pathogens.

생체시료내 약물의 HPLC 분석법에 대한 유효성 검토방법 (Validation Process of HPLC Assay Methods of Drugs in Biological Samples)

  • 지상철;전흥원
    • Journal of Pharmaceutical Investigation
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    • 제21권3호
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    • pp.179-188
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    • 1991
  • An HPLC assay method of a drug to be applied to the pharmacokinetic studies of the drug should be completely validated. The validation process for an HPLC assay method in a biological sample was discussed using the data obtained from the development of HPLC method for the simultaneous quantitation of verapamil and norverapamil in human serum. The validation criteria included were specificity, linearity, accuracy, precision, sensitivity, recovery, drug stability, and ruggedness of an assay method.

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Decal Method with High Catalyst Transfer Ratio and Its Performance in PEMFC

  • Park, Hyun-Seo;Cho, Yong-Hun;Cho, Yoon-Hwan;Sung, Yung-Eun
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2007년도 춘계학술대회
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    • pp.169-171
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    • 2007
  • A breaking layer was introduced to conventional decal transfer method in membrane electrolyte assembly fabrication for high catalyst transfer ratio. In this study, the modified decal transfer method with high catalyst transfer ratio was introduced and its performance is studied. The structural features of electrodes made by decal method were investigated using scanning electron microscopy and current-voltage polarization measurement.

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Sol-Gel법을 통한 리튬 기반 전해질에 적합한 니켈 산화물 박막의 제조와 리튬 기반 전해질에서의 전기변색 특성 (Fabrication of Nickel Oxide Thin Film for Lithium Based Electrolyte by Sol-Gel Method and Electrochromic Properties in Lithium Based Electrolyte)

  • 박선하;유성종;임주완;윤성욱;차인영;성영은
    • 전기화학회지
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    • 제12권3호
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    • pp.251-257
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    • 2009
  • In this study, we fabricated nickel oxide thin film for lithium based electrolyte using sol-gel method. This film was deposited by dip-coating method with mixed solvent of DameH (N,N-dimethylaminoethanol) and DI water. As changing the ratio between DmaeH and DI water, nickel oxide thin film was presented in different charge density and optical transmittance because they were shown various thickness. It was accounted for changing viscosity and density by the ratio of DmaeH and DI water. The thin film synthesized with 1 : 1 ratio of DmaeH and DI water was expressed best electrochromic performance in lithium based electrolyte, because of thick thickness but porous structures.

A Comparison of Methods for Estimating the Productivity of Zostera marina

  • Park, Sang-Rul;Li, Wen-Tao;Kim, Seung-Hyeon;Kim, Jae-Woo;Lee, Kun-Seop
    • Journal of Ecology and Environment
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    • 제33권1호
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    • pp.59-65
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    • 2010
  • Because seagrass production significantly contributes to the biodiversity and production of coastal and estuarine ecosystems, accurate estimation of seagrass productivity is a critical step toward understanding the ecological roles of seagrass in these ecosystems. To develop an accurate and effective method of measuring seagrass productivity, we estimated leaf productivity of eelgrass (Zostera marina) on the southern coast of Korea using three methods, the conventional leaf marking method, the elongation-mass method (Short '87 method), and the plastochrone method. In each season, shoots were pierced through the bundle sheath using a hypodermic needle and were collected after 2-4 weeks had elapsed to estimate their productivity. The leaf elongation and the leaf plastochrone intervals varied significantly among seasons. On an annual basis, the conventional leaf marking method showed the lowest leaf productivity estimates compared to the elongation-mass method and the plastochrone method, suggesting that the conventional leaf marking method underestimated leaf productivity as it ignored leaf maturation processes and new leaf growth within the sheath. Since the elongation-mass method considered leaf maturation processes, this method produced higher leaf productivity estimates than the conventional leaf marking method. On an annual basis, the plastochrone method produced the highest leaf productivity estimates. Below-ground productivity, which can be easily estimated using the plastochrone method, ranged between 3.29 and 5.73 (mg dry weight $shoot^{-1}\;day^{-1}$) and accounted for about 17.8% to 30.3% of total productivity. Because of the high contributions of below-ground productivity to total seagrass production, we suggest that the plastochrone method is an effective and simple technique for assessing both above- and below-ground productivities.

Identification of Irradiated Foods by Using DNA, Immunochemical, and Biological Methods

  • Kim, Kyeung-Eun;Yang, Jae-Seung
    • Preventive Nutrition and Food Science
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    • 제4권4호
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    • pp.276-282
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    • 1999
  • Ionizing radiation is considered to be an efficient technology to improve food safety and to extend food shelf-life in the food industry, and it has been used in food processing with a number of attributes. Food labeling should be established to enable the consumer to choose food freely, based on label information. A variety of methodologies to determine the physical, chemical, microbiological, and biological changes due to irradiation has been investigated in order to discriminate the irradiated and unirradiated food products for the consumer's free choice in food selection. However, no satisfactory method has been developed so far. In this review, various approaches based on DNA, immunochemical, and biological methods are addressed.

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Gene Discovery Analysis from Mouse Embryonic Stem Cells Based on Time Course Microarray Data

  • Suh, Young Ju;Cho, Sun A;Shim, Jung Hee;Yook, Yeon Joo;Yoo, Kyung Hyun;Kim, Jung Hee;Park, Eun Young;Noh, Ji Yeun;Lee, Seong Ho;Yang, Moon Hee;Jeong, Hyo Seok;Park, Jong Hoon
    • Molecules and Cells
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    • 제26권4호
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    • pp.338-343
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    • 2008
  • An embryonic stem cell is a powerful tool for investigation of early development in vitro. The study of embryonic stem cell mediated neuronal differentiation allows for improved understanding of the mechanisms involved in embryonic neuronal development. We investigated expression profile changes using time course cDNA microarray to identify clues for the signaling network of neuronal differentiation. For the short time course microarray data, pattern analysis based on the quadratic regression method is an effective approach for identification and classification of a variety of expressed genes that have biological relevance. We studied the expression patterns, at each of 5 stages, after neuronal induction at the mRNA level of embryonic stem cells using the quadratic regression method for pattern analysis. As a result, a total of 316 genes (3.1%) including 166 (1.7%) informative genes in 8 possible expression patterns were identified by pattern analysis. Among the selected genes associated with neurological system, all three genes showing linearly increasing pattern over time, and one gene showing decreasing pattern over time, were verified by RT-PCR. Therefore, an increase in gene expression over time, in a linear pattern, may be associated with embryonic development. The genes: Tcfap2c, Ttr, Wnt3a, Btg2 and Foxk1 detected by pattern analysis, and verified by RT-PCR simultaneously, may be candidate markers associated with the development of the nervous system. Our study shows that pattern analysis, using the quadratic regression method, is very useful for investigation of time course cDNA microarray data. The pattern analysis used in this study has biological significance for the study of embryonic stem cells.