• Title/Summary/Keyword: Preservation method

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A simple mid-term preservation method (SMPM) of plant callus under low temperature conditions (저온 보존을 이용한 간편 중기 식물캘러스 저장법)

  • Park, Sung-Chul;Park, Su Hyun;Kim, Soyoung;Jeong, Yu Jeong;Kim, Cha Young;Jeong, Jae Cheol
    • Journal of Plant Biotechnology
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    • v.49 no.3
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    • pp.187-192
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    • 2022
  • The repeated monthly or weekly subculture of plant callus is labor intensive and increases the risk of somaclonal variation from the parental callus line. The most effective method for preserving plant callus is cryopreservation, which involves storage in liquid nitrogen. However, this method cannot be applied to the callus of different plant species in the same manner, so it is difficult to develop a standardized cryopreservation method. In addition, the survival rate of the frozen callus after thawing and the regeneration rate after survival are uncertain. Therefore, it is necessary to develop a method to extend the subculture interval of plant callus in an active state. In this study, active plant calli of various species without freezing was incubated at 15℃ for 4 to 12 weeks without subculture. After 12 weeks, 8 lines of plant callus grew less than 2-fold when cultured at 25℃, but at least 2 times as much when cultured at 15℃. Moreover, total antioxidant activity did not differ significantly between plant callus recovered at 25℃ after culturing at 15℃ or at 25℃. These results show that the subculture interval can be extended at a temperature of 15℃ without need for modified medium composition or additional processes. In addition, positive results in all calli of several plant species are expected to reduce labor as well as somaclonal variation by increasing the subculture.

Changes in Immunogenicity of Preserved Aortic Allograft (보존된 동종동맥편 조직의 면역성 변화에 관한 연구)

  • 전예지;박영훈;강영선;최희숙;임창영
    • Journal of Chest Surgery
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    • v.29 no.11
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    • pp.1173-1181
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    • 1996
  • The causes of degenerative changes in allograft cardiac valves are not well known to this day. Today's preserved allografts possess highly viable endothelial cells and degeneration of allografts can be facilitated by immune reaction which may be mediated by these viable cells. To test the antigenicity of endothelial cells, pieces from aortic wall were obtained from fresh and cryo-preserved rat allograft. Timings of sampling were prior to sterilization, after sterilization, after 1, 2, 7, 14 days of fresh preservation and cryopreservation. Endothelial cells were tested by immunohistochemical methods using monoclonal antibodies to MHC class I(MRC OX-18), class II(MRC OX-6) and ICAM-1 antigens. After transplantation of each group of aortic allograft at the subcutaneous layers of rats, population of CD4$^{+}$ T cell and CD8$^{+}$ T cell were analyzed with monoclonal antibodies after 1, 2, 3, 4, 6 and 8 weeks. MHC class I expression was 23.95% before preservation and increased to 35.53~48.08% after preservation(p=0.0183). MHC Class II expression was 9.72% before preservation and 10.13~13.39% after preservation(P=0.1599). ICAM-1 expression was 15.02% before preservation and increased to 19.85~35.33% after preservation(P=0.001). The proportion of CD4$^{+}$ T-cell was 42.13% before transplantation. And this was 49.23~36.8% after transplantation in No treat group (p=0.955), decreased to 29.56~32.80% in other group(p=0.0001~0.008). In all the groups, the proportion of CD8$^{+}$ T-cell increased from 25.57% before transplantation to 42.32~58.92% after transplantation(p=0.000l~0.0002). The CD4$^{+}$/CD8$^{+}$ ratio decreased from 1.22~2.28 at first week to 0.47~0.95 at eighth week(p=0.0001). The results revealed that the expression of MHC class I and ICAM-1 in aortic allograft endothelium were increased but that of MHC class II were not changed, despite the different method of preservation. During 8 weeks after transplantation of aortic allograft, the subpopulations of CD4$^{+}$ T cell were not changed or only slightly decreased but those of CD8$^{+}$ T cell were progressively increased.ely increased.

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The Residents' Perception and the Application of Contingent Valuation Method for Green Areas in Apartment Housing Blocks (아파트 단지의 녹지조성에 대한 주민의식과 가상평가법 적용에 관한 연구)

  • 김한수;김재홍
    • Journal of the Korean housing association
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    • v.13 no.5
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    • pp.59-69
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    • 2002
  • This study is designed to derive a cost estimation method for the management of green areas in apartment housing blocks. For this purpose, quantity of green areas, their usages, management techniques were analyzed through a survey of residents. In this process, contingent valuation method(CVM) is utilized to evaluate the cost of green areas. The survey was conducted for about two weeks in June of 2002. The amount of willingness to pay(WTP) for green area management is calculated by the CVM program. The findings are as follows; First, the residents want more green areas in their apartment blocks, as well as in the surrounding urban areas, due to the shortage of green areas in their living environments. Second, the residents' opinion on green area is summarized as that of natural environment protectionist - it helps living environment to be more amenable and contributes the preservation of urban and global environments. This fact can be interpreted as the peoples profound recognition toward green areas. Third, the contingent valuation method(CVM) is suitable to evaluate WTP for management costs of green areas. Fourth, more than half of the residents(61.6%) agreed upon the costs of green area supply and management. calculated by the CVM. Estimated WTP is ₩ 1,900~2,400 per month per household.

Simultaneous Detection of Yersinia enterocolitica, Staphylococcus aureus, and Shigella spp. in Lettuce Using Multiplex PCR Method

  • Park Si-Hong;Kim Hyun-Joong;Kim Hae-Yeong
    • Journal of Microbiology and Biotechnology
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    • v.16 no.8
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    • pp.1301-1305
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    • 2006
  • The development of rapid, infallible, and sensitive methods of detecting foodborne pathogens has received much impetus in recent years owing to an increased public awareness of the health hazards. For the rapid and simultaneous detection of these foodborne pathogens, a multiplex PCR method was developed. Yersinia enterocolitica, Staphylococcus aureus, and Shigella spp. are bacteria of concern because of their specific growing condition that enables them to live at low temperatures. In order to detect each pathogenic bacterium, specific primers from Y. enterocolitica, St. aureus, and Sh. flexneri were selected and validated successfully. To apply this method to food stored at low temperature, Y. enterocolitica, St. aureus, and Sh. flexneri were artificially inoculated in lettuce and incubated for enrichment. The multiplex PCR assays were able to simultaneously detect three pathogens, and the presence of three bands was observed at initial inoculation levels of approximately 1$\times$10$^1$ CFU/g in lettuce. Therefore, this method could be used for simultaneous detection of Y. enterocolitica, St. aureus, and Shigella spp. contaminated in lettuce during cultivation, transportation, preservation, and storage.

Field Application of Insulation Curing Method with Double Bubble Sheets Subject to Cold Weather (이중버블시트를 이용한 단열양생공법의 한중콘크리트 현장적용)

  • Hong, Seak-Min;Baek, Dae-Hyun;Kim, Jong;Jeon, Chung-Kun;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.05a
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    • pp.57-60
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    • 2008
  • This study investigated the results of insulation heat curing method using double layer bubble sheet in slab concrete and mass concrete in cold weather environment. First of all, when double bubble sheets are applied, it was shown that slab concrete was protected from early freezing by remaining between 6 and 15℃ even in case outside temperature drops -9℃ below zero until the 2nd day from piling, and in the case of mass concrete, with the maximum temperature difference between the center and surface less than 4℃, crack occurrence index was close to 2 and no hydration heat crack occurred by internal constraint. The insulation heat preservation curing method using the double bubble sheet applied in this field prevented early freezing owing to stable curing temperature management, deterring concrete strength development delay at low temperature, and obtained the needed strength. Also, it was proven that the method is highly effective and economic for cold weather concrete quality maintenance through curing cost reduction like construction period shortening and labor cost reduction, etc by reducing the process of temporary equipment installation and disassembling.

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Calculation of Electron concentration and Electrostatic potential profile for $Al_{x}Gal{-x}As/Ga_{x}In1$_{-x}$As/GaAs HEMT device by 2-Dimensional Quantum Mechanical analysis) (2차원 양자 역학적 해석에 의한 고속 통신용 $Al_{x}Gal{-x}As/Ga_{x}In1$_{-x}$As/GaAs HEMT 소자의 전자 농도 및 전위분포 계산)

  • 송영진;황호정
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.3
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    • pp.76-87
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    • 1993
  • We present a self-consistent, 2-dimensional solution of the Poisson and Sch rodinger equation based on the finite difference method with a nonuniform mesh size for a AlGaAs/GaInAs/GaAs HEMT devide. During the interative self-consistent calculation, however, we calculate Schrodinger equation only a some region of device, not a fully region in order to save the moemory and the speed-up of computation, and then use the approximated data for the other region using by a interpolation method with a given values. Also we adopt the proper matrix transformation method that allows preservation of the symmetric, form of the discretized Schrodinger equation, even with the use of a nonumiform mesh size, therefor, can reduce the computation time. We calculate the wavefunction, eigenstates and the electron concentration uat channel layer nder the thermal equilibrium and the biased conditions, respectively. Also,these parameters are used to solve 2-dimensional tdistribution of potential in he entire region of device. It is proved that the method is very efficient in finding eigenstages extending over relatively large spatial area without loss of accuracy. So, it can be used rather easily in any sarbitrary modulation doped utucture.

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Field Application of Insulation Curing Method for the Concrete applying Double Layer Bubble Sheets Subjected to Cold Weather (이중버블시트를 이용한 단열보온 양생공법의 한중콘크리트 현장적용)

  • Hong, Seak-Min;Son, Ho-Jung;Oh, Chi-Hyun;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.05a
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    • pp.83-85
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    • 2011
  • This study investigated the results of insulation heat curing method using double layer bubble sheet in concrete in cold weather environment. First of all, when double bubble sheets are applied, it was shown that concrete was protected from early freezing by remaining between 7℃ and 3℃ even in case outside temperature drops -7℃ below zero until the 3d day from piling. The insulation heat preservation curing method using the double bubble sheet applied in this field prevented early freezing owing to stable curing temperature management, deterring concrete strength development delay at low temperature, and obtained the needed strength. Also, it was proven that the method is highly effective and economic for cold weather concrete quality maintenance through curing cost reduction like construction period shortening and labor cost reduction, etc by reducing the process of temporary equipment installation and disassembling.

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Aesthetic-Measure, and Visual Preference of Environmental Colors in Korea Rural Town (농촌마을 환경색채 미도(美度)와 선호도 관계 및 적용성 연구)

  • Lee, Young;Ahn, Tong-Mahn
    • Journal of Korean Society of Rural Planning
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    • v.16 no.2
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    • pp.11-19
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    • 2010
  • Pro-environmental life styles, foundations of a collective civilization and preservation of our tradition at rural communities hold a great public profit value, of which importance has been strongly emphasized during last decade. Here, the environmental color is one of the most influential elements that determine the image of the rural landscape. Whenever an alternative color element is introduced to rural town, it is very important to examine its effect on the existing environmental color. Typically, a preference-surveying method has been used to evaluate the suitability of such environmental color balance. However, we note that the reliability of this method is limited by the subjectivity of a respondent. And thus, it is highly desirable to develop a more objective method. We propose a feasibility study for using an aesthetic-measure to evaluate the environmental color of a rural town. In this work, we looked into the validity of our approach by comparing its result with that of the preference-based-method as a way to determine the environmental color. Our study is based on 20 photo images from Ansung-city Yangsung-myeon Donghang 2ri Kyo-dong town in Kyongki Province.

Field Application of Insulation Curing Method with Double Bubble Sheets Subject to Cold Weather (이중버블시트를 이용한 단열양생공법의 한중콘크리트 현장적용)

  • Hong, Seak-Min;Lee, Il-Sun;Baek, Dae-Hyun;Kim, Jong;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.05b
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    • pp.25-28
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    • 2009
  • This study investigated the results of insulation heat curing method using double layer bubble sheet in slab concrete in cold weather environment. First of all, when double bubble sheets are applied, it was shown that slab concrete was protected from early freezing by remaining between 5 and $l0^{\circ}C$ even in case outside temperature drops $-11^{\circ}C$ below zero until the 4nd day from piling. The insulation heat preservation curing method using the double bubble sheet applied in this field prevented early freezing owing to stable curing temperature management, deterring concrete strength development delay at low temperature, and obtained the needed strength. Also, it was proven that the method is highly effective and economic for cold weather concrete quality maintenance through curing cost reduction like construction period shortening and labor cost reduction, etc by reducing the process of temporary equipment installation and disassembling.

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A Method for Making Kimchi Containing Snow Crab in a COVID-19 Environment

  • CHOI, Eun-Mee;KWON, Lee-Seung
    • Journal of Wellbeing Management and Applied Psychology
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    • v.5 no.1
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    • pp.9-22
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    • 2022
  • Purpose: The purpose of this study is to develop a kimchi recipe for immunity enhancement using snow crab, which has high food value in the era of COVID-19. Research design, data and methodology: The snow crab kimchi manufacturing method of this study includes the steps of preparing a kimchi seasoning containing snow crab seasoning and chitosan powder. Kimchi seasoning is made by adding 5 parts by weight of crab seasoning and 1 part by weight of chitosan powder to 100 parts by weight of the basic kimchi seasoning prepared by mixing radish, minced garlic, minced ginger, onion juice, anchovy sauce, red pepper powder and glutinous rice paste. Results: It was possible to develop new flavors, possibilities and characteristics of snow crab kimchi by extending the health and functional effects, taste, and preservation period without significantly changing the unique manufacturing method, taste and function of kimchi, including snow crab. Conclusions: Snow crab kimchi was excellent in taste and aroma while enhancing the health functions of the body, such as improving people's immunity. The developed snow crab kimchi manufacturing method can not only improve people's health, but also expand the choice of preference for kimchi taste and shelf life.