• Journal of Plant Biotechnology
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• 제37권4호
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• pp.414-424
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• 2010

This report describes recent advances in tissue culture, genetic transformation of commercial rose (Rosa hybrida) and in development of new rose cultivars by molecular breeding. Rose is one of major cut-flowers in global horticulture industry. Successful progresses were made in development of new cultivars for pathogen resistant, environmental stress resistant and petal color modification by molecular breeding. New cultivars, however, has not reported yet in korea, although lots of progresses were achieved in each field of conventional breeding, tissue culture and genetic transformation. Cooperation in these research fields will promote screening of useful genes to have specific traits on rose and exploiting of processes to improve in the efficiency of tissue culture and genetic transformation of rose, therefore, we hopefully expect that new rose cultivars by molecular breeding will be released in the near future.

• Mycobiology
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• 제38권4호
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• pp.331-335
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• 2010

In this study, we developed an efficient electroporation-mediated transformation system featuring Flammulina velutipes. The flammutoxin (ftx) gene of F. velutipes was isolated by reverse transcription-PCR. pFTXHg plasmid was constructed using the partial ftx gene (410 bp) along with the hygromycin B phosphotransferase gene (hygB) downstream of the glyceraldehydes-3-phosphate dehydrogenase (gpd) promoter. The plasmid was transformed into protoplasts of monokaryotic strain 4019-20 of F. velutipes by electroporation. High transformation efficiency was obtained with an electric-pulse of 1.25 kV/cm by using 177 transformants/${\mu}g$ of DNA in $1{\times}10^7$ protoplasts. PCR and Southern blot hybridization indicated that a single copy of the plasmid DNA was inserted at different locations in the F. velutipes genome by non-homologous recombination. Therefore, this transformation system could be used as a useful tool for gene function analysis of F. velutipes.

• 농촌계획
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• 제24권2호
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• pp.79-89
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• 2018

The main purpose of this study is to explore the factors that affect the transformation of over-depopulated rural villages. Specifically, we investigated the reasons of the rapid decrease in the number of over-populated rural villages shown by recent census data in spite of the continuing decrease of population in rural area. We used a binary-logit model and the Census of Agriculture, Forestry and Fisheries data(2010, 2015). The main results are summarized as followed: First, the over-depopulated rural villages with strong agronomic base are more likely to exit from over-depopulation. Second, returners from urban to rural have a positive impacts on the revival of over-depopulated rural areas. Thirds, improving the basic services accessibility of rural residents is also critical for keeping rural community more sustainable. These findings can be used to make effective strategies to revive the depopulated rural villages.

• Journal of Plant Biotechnology
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• 제43권1호
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• pp.66-75
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• 2016

Agrobacterium-mediated gene transfer has recently been developed to improve rice transformation. In this study, 3 different transformation methods were tested including soaking, co-cultivation, and vacuum infiltration. Agrobacterium tumefaciens GV3101 harboring the binary vector pGreen:: LeGSNOR was used in this experiment. This study aimed to identify the most appropriate method for transferring LeGSNOR into rice. Vacuum infiltration of the embryonic calli for 5 min in Ilpum resulted in high transformation efficiency based on confirmation by PCR, RT-PCR, and qRT-PCR analyses. In conclusion, we described the development of an efficient transformation protocol for the stable integration of foreign genes into rice; furthermore, the study results confirmed that PCR is suitable for efficient detection of the integrated gene. The vacuum infiltration system is a potentially useful tool for future studies focusing on transferring important genes into rice seed calli, and may help reduce time and effort.

• 소성∙가공
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• 제32권2호
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• pp.53-60
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• 2023

A wide range of grain size was achieved in a Fe-Cr-Mn austenitic stainless steel (STS) by cold rolling and reversion annealing. The tensile characteristics of the STS were analyzed in terms of the dependence of strain induced martensitic (SIM) transformation on the grain size. In the ultrafine grain regime, the steel showed a high yield strength over 1 GPa, a discontinuous yielding, and a prolonged yield point elongation followed by considerable strain hardening. By increasing the grain size, the discontinuous yielding diminished and the yield point elongation decreased. The microstructural examination revealed that these tensile characteristics are closely related to the suppression of SIM transformation with decreasing the grain size. Especially, the prolonged yield point elongation of the ultrafine grained STS was found to be associated with development of unidirectional ε martensite bands. Based on the microstructural examination of the deformed microstructures, the rationalization of the grain size dependence of SIM transformation was suggested.

• 아동학회지
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• 제25권6호
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• pp.337-354
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• 2004

This study investigated the relationship between pretend play and comprehension of pretense by type of stipulated transformation among 2-and 4-year-olds children. Each child participated in pretend play with its mother for 10 minutes and in a stipulated task for comprehension of pretense. There was a significant difference in 2- and 4-year-olds in frequency and level of pretend play, and pretend play behavior was related to comprehension of pretense. Level of pretend play was positively related to comprehension of 'complexity' of stipulated transformations. This showed that there was significant relationship between development of pretend play and ability to comprehend pretense based on physical transformation.

• 한국분말재료학회지
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• 제29권5호
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• pp.382-389
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• 2022

A typical trade-off relationship exists between strength and elongation in face-centered cubic metals. Studies have recently been conducted to enhance strength without ductility reduction through surface-treatment-based ultrasonic nanocrystalline surface modification (UNSM), which creates a gradient microstructure in which grains become smaller from the inside to the surface. The transformation-induced plasticity effect in Fe-Mn alloys results in excellent strength and ductility due to their high work-hardening rate. This rate is achieved through strain-induced martensitic transformation when an alloy is plastically deformed. In this study, Fe-6%Mn powders with different sizes were prepared by high-energy ball milling and sintered through spark plasma sintering to produce Fe-6%Mn samples. A gradient microstructure was obtained by stacking the different-sized powders to achieve similar effects as those derived from UNSM. A compressive test was performed to investigate the mechanical properties, including the yielding behavior. The deformed microstructure was observed through electron backscatter diffraction to determine the effects of gradient plastic deformation.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.370-378
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• 2010

This review describes the stratagies of development of virus-resistant Alstroemeria plants using the genetic modification system. Despite of increasing of its importance in cut flower market, improvements of some horticultuirally important traits such as fragrance, long vase-life, virus resistance and tolerance against abiotic stresses are lack of the breeding program in Alstroemeria. Of these traits, virus-resistance is quite difficult to develop in Alstroemeria plants due to the limitations of genetic variation in the existed germplasm. To extend the genetic variation, plant biotechnological techniques such as genetic transformation and tissue culture should be combined to develop virus-resistant line in Alstroemeria. In this review, several strategies for the generation of virus-resistance by using natural resistance genes, pathogen-derived genes and other sources including pathogen-derived proteins, virus-specific antibodies and ribosome-inactivating proteins are presented. Also, brief histories of breeding, tissue culture, and transformation system in Alstroemeria plants are described to inderstand of the application of transgenic approach for the development of virus-resistance in Alstroemeria species.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권11호
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• pp.1091-1095
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• 2010

기존의 스마트폰용 소프트웨어 개발은 플랫폼에 종속적으로 만들어 지기 때문에 플랫폼별로 개발해야한다. 애플은 코코아플랫폼, 구글은 안드로이드, 마이크로소프트는 윈도우 모바일 퉁 각 벤더마다 고유의 플랫폼으로 개발한다. 본 논문에서는 한 번의 개발을 통해 이종의 소프트웨어 개발할 수 있도록 모델변환기법을 적용한다. 이 방법은 독립 모델과 종속 모델을 분리하고 이 둘의 차이를 변환언어를 통해 자동 변환하는 기법이다. 모델 변환 기법 수행을 위해서는 모델, 메타모델, 모델변환언어가 요구된다. 본 논문에서는 스마트폰에 적용하기 위해서 모델은 UML, 메타모델은 UML 메타모델, 모델변환언어는 ATL을 사용하였다. 적용사례로 윈도우 모바일 플랫폼환경에서 모델변환을 이용하여 개발하는 방법을 보여준다. 본 논문의 플랫폼 독립모델을 사용하고 모델 변환 규칙을 재정의 하면 아이폰, 안드로이드 등의 이종의 플랫폼으로 변환이 가능하다.

• 한국해안해양공학회지
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• 제4권4호
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• pp.225-230
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• 1992

수심의 변화 또는 흐름의 영향에 의한 파낭 스펙트럼의 변환을 이해하기 위한 노력으로 최근 발표된 연구논문들의 종합 및 분석을 시도하였다. 본 논문의 내용은 파낭 스펙트럼의 일차원 변환에 대한 천수 및 흐름의 영향과 연안역에서의 파낭변환을 위한 수리 및 수치 모형에서 불규칙파를 규칙파로 충약화시키는 문제의 적합성을 검토하는데 국한되어 있다.