• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1301-1305
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• 2009

The evolution of living organisms occurs via a combination of highly complicated processes that involve modification of various features such as appearance, metabolism and sensing systems. To understand the evolution of life, it is necessary to understand how each biological feature has been optimized in response to new environmental conditions and interrelated with other features through evolution. To accomplish this, we constructed contents-based trees for a two-component system (TCS) and metabolic network to determine how the environmental communication mechanism and the intracellular metabolism have evolved, respectively. We then conducted a comparative analysis of the two trees using ARACNE to evaluate the evolutionary and functional relationship between TCS and metabolism. The results showed that such integrated analysis can give new insight into the study of bacterial evolution.

• 식물분류학회지
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• 제42권1호
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• pp.13-23
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• 2012

trnL-F 지역은 엽록체 게놈 large single-copy 지역에 위치하며, trnL gene, trnL intron, trnL-F IGS로 구성된다. 본 연구는 한국산 꿩의다리속 내에서 trnL-F 지역의 분자진화와 유연관계를 분석하였다. 갭형질을 이용한 자료의 베이시안과 파시모니 분석에서 몇몇 indels evolution는 분계조를 지지하여 해상력이 좋은 계통수가 나타났다. 한국산 꿩의다리속 내에 cpDNA trnL-F 지역의 indel events는 계통학적으로 유용한 정보를 가지고 있는 것으로 판단된다. 산꿩의다리절(그늘꿩의다리 제외)은 속내에서 가장 먼저 분기한 것으로 나타났고, 나머지 절은 강하게 분계조를 형성하며 분기하였다. 한국산 꿩의다리속 내에 trnL-F 지역은 뉴클레오티드의 다양한 공간적 분포 변이와 주로 transversion에 따른 염기치환 등 다양한 진화적 패턴을 가지고 있었다.

• Journal of Information Technology Applications and Management
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• 제22권3호
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• pp.143-167
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• 2015

This paper addresses the issue how the total life cycle cost may be minimized and how the cost should be allocated to the acquirer and developer. This paper differentiates post life cycle change (PLCC) endeavors from PLCC activities, rigorously classifies PLCC endeavors according to the result of PLCC endeavors, and rigorously defines the life cycle cost of a software product. This paper reviews classical definitions of software 'maintenance' types and proposes a new typology of PLCC activities too. The proposed classification schemes are exhaustive and mutually exclusive, and provide a new paradigm to review existing literatures regarding software cost estimation, software 'maintenance,' software evolution, and software architecture from a new perspective. This paper argues that the long-term interest of the acquirer is not protected properly because warranty period is typically too short and because the main concern of warranty service is given to removing the defects detected easily. Based on the observation that defects are caused solely by errors the developer has committed for software while defects are often induced by using for hardware (so, this paper cautiously proposes not to use the term 'maintenance' at all for software), this paper argues that the cost to remove defects should not be borne by the acquirer for software.

• 한국초등과학교육학회지:초등과학교육
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• 제24권2호
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• pp.145-159
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• 2005

Students' alternative concepts of evolution are similar to misconcepts and disputes which scientists had in science history. The aims of this study are to analyze the elementary children's concept in evolution based on science history. Lee (2004)'s two tests were applied to 6th grade to investigate the children's evolution concepts and genetic concepts related to the historical development of the evolution concepts. The test results were analyzed in accordance with 4 stages of science history based on Lee (2004)'s method. These stages are divided to stage 1 (Before Lamarck), stage 2 (Lamarck), stage 3 (Darwin), stage 4 (After Darwin). The major results are as follows. Most of elementary school children are fixed to the stage 2. They usually do not show the consistency of evolution concepts in the three dimensional aspects such as mechanism, time, and subjects. Many children do not have concrete meaning of gene, inheritance, sexual reproduction, mutation and could not connect these concetps and process of evolution. Also, they believe the inheritance of acquired traits and spontaneous generation. Therefore it is confirmed that they still have similar misconcepts and disputes which scientists had in transition time between stage 2 and 3 and most of children already have strong Lamarckian thought acquired from daily life experience before learning about natural selection and evolution.

• Animal Systematics, Evolution and Diversity
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• 제36권4호
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• pp.354-362
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• 2020

A common snapping turtle Chelydra serpentina inhabiting North America is internationally protected as an endangered species. It is known that the individuals of common snapping turtles were imported to South Korea as pets, and after being abandoned, some inhabit the natural ecosystem of South Korea like wild animals. No genetic survey has yet been performed for the common snapping turtles imported to South Korea. Hereby, cytochrome c oxidase subunit I (COI) information, which is 594 bp long, was determined for a total of 16 C. serpentina individuals, of which one was found in nature, twelve legally imported and their descendants, and the other three were provided from the Kansas Herpetological Society, USA. The obtained data were combined with thirteen COI sequences of C. serpentina retrieved from NCBI GenBank for the subsequent population genetic analyses. The results showed that there exist five haplotypes with high sequence similarity (only three parsimoniously informative sites). In the TCS and phylogenetic analyses, all the examined C. serpentina samples coincidently formed a strong monoclade with those collected mostly from Kansas State, USA, indicating that the imported ones to South Korea are from the central North America. In addition, there found the amino acid changes and the high degree of nucleotide sequence differences between C. serpentina and C. rossignoni with some important morphological characters. It is expected that the present results could provide an important framework for systematic management and control of exotic snapping turtles imported and released to nature of South Korea.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2006년도 제47회 학술심포지움 및 추계국제학술대회
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• pp.97.2-97.2
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• 2006

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.24.1-24.1
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• 2007

See Full Text

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2006년도 한국육종학회 공동심포지엄 및 학술대회
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• pp.40.1-40.1
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• 2006

• Animal Systematics, Evolution and Diversity
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• 제25권1호
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• pp.137-139
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• 2009

Marine sponges were collected from Tongyeong yachtschool harbor, Korea in 2008. Among them Halichondria (Halichondria) bowerbanki Burton, 1930 is newly recorded in the Korean fauna.

• Journal of the Korean Wood Science and Technology
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• 제23권4호
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• pp.46-53
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• 1995

The anatomy of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens was described and analyzed. Sixteen wood anatomical characters, habit and phenology factors were determined by simple correlation and principal component analysis. Strong positive correlations were found between vessel element length and fiber length, ray width and ray height, simple pits of fiber wall and paratracheal parenchyma distribution. The results of principal component analysis (PCA) disclose the primitive characteristics and the direction of xylem evolution of Korean diffuse-porous woods. The xylem evolution scenario for Korean dicotyledonous woods is considered to be developed in the direction of decreasing trends of vessel frequency, vessel element length, and length/diameter(L/D) ratio of vessel element but increasing trends of vessel diameter, fiber length/vessel element length(F/V) ratio, libriform wood fibers, simple perforation, and homogeneous ray composition. Increase of vessel diameter and decrease of vessel frequency seem to be related to the improvement of conductive efficiency, and increase of the vessel element length and occurrence of scalariform perforation in vessel element may be related to enhanced of conductive safety. Also the libriform wood fibers and ray features appear to have relationship with mechanical support and nutrient metabolism, respectively.