• Title/Summary/Keyword: Evolution

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Effect of Photosynthesis on Ozone-Induced Ethylent Evolution from Tomato Plants (토마토 식물에 있어서 광합성이 유존유동성의 에틸렌 생성에 미치는 영향)

  • 배공영
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.3
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    • pp.307-314
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    • 1996
  • The rate of evolution of ethylent by tomato plants was rapidly increased by ozone fumigation. In the present study, the mechanism of ethylent evolution by ozone was investigated in experiments with aminoethoxyvinylglycine (AVG) and tiron, which inhibit the formation of ethylene and peroxidation of lipids, respectively. Pretreatment with AVG significantly inhibited the ozone-induced ethylent evolution, but the treatment of plants with tiron did not inhibit. These results indicate that the induction of the evolution of ethylene by ozone involves the pathway via aminocyclopropane-1-carboxylate (ACC), while not released as a result of the peroxidation of lipids. Ozone-induced ethylent evolution was greater in dar- than light-incubated, intact tomato plants. The difference between dark- and light-ethylene evolution was examined with diuron, an inhibitor of photosynthetic electron transport. The inhibitor treatment promoted ethylent evolution. These results suggest that ethylent retention and metabolism in plants were regulated by internal $CO_2$ levels which, in turn, were controlled in large part by photosynthesis. Thus, ethylene was retained in illuminated leaf tissue under low intenal $CO_2$ concentration which may develop in a sealed container without exogenously supplied $CO_2$.

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Ethylene Evolution in Tomato Plants by Ozone in Relation to Leaf Injury (토마토 오존처리에 의한 에틸렌 생성과 가시 장해 발현과의 관계)

  • 배공영;이용범
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.3
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    • pp.333-340
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    • 1996
  • The relationship between ozone-induced damages and ethylend evolution was examined in tomato plants fumigated with ozone of 0.2 $\mu\ell/\ell$. The rate of evolution of ethylent by tomato plants was enhanced by ozone fumigation. Pretreatment of leaves with aminoethoxyvinylglycine (AVG), an inhibitor of ethylene evolution, significantly inhibited the evolution of ethylene that was induced by ozone and concomitantly reduced the extent of ozone-induced visible damage to leaves. Treatment with 2,5-norbonadiene (NBD), and inhibitor of the action of ethylene, strongly reduced the extent of visible damage caused by ozone, even though it did not suppress the evolution of ethylene. These results indicated that ethylene might play an important role in ozone-induced plant injuries at relatively short terms of ozone fumigation. Next, we examined the effect of tiron, a scanvenger of the free-radical, on evolution of ethylene and leaf injury caused by ozone. Tiron treatment strongly reduced the extent of ozone-induced injury, but had not inhibitory effect on the evolution of ethylene from tomato leaves. This result suggests the involvement of free-radical, such as superoxide radicals, in induction of injuries caused by ozone.

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Case Study of Teaching Practices of Biology Teachers with and without Research Experience in Evolution Education (진화 교육 연구 경험 유무에 따른 생명과학 교사의 교수 실행 사례 연구)

  • Ko, Yuseon;Cha, Heeyoung;Lim, Mili
    • Journal of The Korean Association For Science Education
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    • v.37 no.4
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    • pp.747-761
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    • 2017
  • The purpose of this study is to analyze differences in the teaching practices of biology teachers according to their awareness of the importance of evolution. For this purpose, two teachers who experienced study of evolution and recognized its importance, along with two teachers with no experience in evolution education in the comparison group, were included in the sample. To observe teaching practices, two classes each on biological evolution and non-evolution were selected, recorded and transcribed. The content analyzed included the teachers' view on evolution education and teachers' evolution concepts reflected in teaching practice. As a result, the level of understanding of the teachers' evolution concept was unrelated to teachers' awareness of the importance of evolution. Instead, each teacher would not feel the need for religious beliefs or awareness of the importance of evolution to have a negative impact on the awareness of the importance of evolution. Inexperienced teachers tend to reject the retraining opportunities to recognize the importance of evolution. In addition, inexperienced teachers were only superficially aware of the evaluation and improvement of evolution presented in textbooks and curricula. In actual teaching practice analysis, inexperienced teachers' utilizing ratio of the evolution key concept was higher than that of experienced teachers. Only experienced teachers were aware of the misconceptions presented in their execution and described the causes that appear in these misconceptions. Teachers who recognized the importance of evolution were widely using the key concepts of evolution, as well as more practical in preventing the misconceptions related to evolution forms. It indicates that biology teachers who do not realize the importance of evolution in biology education need to experience explicit and practical education programs as well as instructional materials on evolution.

Evolution of Human Locomotion: A Computer Simulation Study (인류 보행의 진화: 컴퓨터 시뮬레이션 연구)

  • 엄광문;하세카즈노리
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.5
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    • pp.188-202
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    • 2004
  • This research was designed to investigate biomechanical aspects of the evolution based on the hypothesis of dynamic cooperative interactions between the locomotion pattern and the body shape in the evolution of human bipedal walking The musculoskeletal model used in the computer simulation consisted of 12 rigid segments and 26 muscles. The nervous system was represented by 18 rhythmic pattern generators. The genetic algorithm was employed based on the natural selection theory to represent the evolutionary mechanism. Evolutionary strategy was assumed to minimize the cost function that is weighted sum of the energy consumption, the muscular fatigue and the load on the skeletal system. The simulation results showed that repeated manipulations of the genetic algorithm resulted in the change of body shape and locomotion pattern from those of chimpanzee to those of human. It was suggested that improving locomotive efficiency and the load on the musculoskeletal system are feasible factors driving the evolution of the human body shape and the bipedal locomotion pattern. The hypothetical evolution method employed in this study can be a new powerful tool for investigation of the evolution process.

The theoretical construction and practical application of Evolution Model for creating the advanced information-technical system;based on mobile device (진보된 정보기술시스템을 창조하기 위한 진화모델의 이론적 구축 및 실제 응용 연구;mobile device를 기준으로)

  • Kim, Sung-Cheol;Shin, Min-Soo
    • 한국IT서비스학회:학술대회논문집
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    • 2006.11a
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    • pp.593-599
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    • 2006
  • Including technical device and general information system, the information-technical(IT) system is defined as the technical system for acquiring, processing, storing and transferring information to a person. This paper presents Knowledge-based Heuristic Evolution Model for creating the advanced information-technical system. This Evolution Model is derived from the historical review on definition of evolution, the research on the architecture of the general IT system, history of IT system, technology innovation theory and multi-case study research. The evolution model is applicable to the conceptual creation of the advanced product in R&D organization requiring development methodologies like rapid-prototyping to develop next generation product. For the detailed theoretical construction and practical application of Evolution Model, the case study research based on action research is performed. the object of the case study is mobile device, especially mobile hand-held phone. Thus, we obtain the Evolution Model for creating the advanced information-technical system.

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A Framework for Software System Evolution using Architectural Transformation Pattern (아키텍처 변환 패턴을 이용한 소프트웨어 시스템 진화 프레임워크)

  • Park, Taehyun;Ahn, Hwi;Kang, Sungwon;Park, Jongbin;Hwang, Sangcheol
    • Journal of Software Engineering Society
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    • v.26 no.1
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    • pp.17-29
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    • 2013
  • Software System Evolution is more planned and systematic maintenance process as well as a type of maintenance. The research of software evolution provides basis of decisions for maintenance value through cost-benefit analysis of legacy system and architecture-based software evolution enables engineers to reduce maintenance cost by automation of repetitive evolution tasks. This paper proposes a framework for software system evolution using architectural transformation pattern.

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ON STOCHASTIC EVOLUTION EQUATIONS WITH STATE-DEPENDENT DIFFUSION TERMS

  • Kim, Jai-Heui;Song, Jung-Hoon
    • Journal of the Korean Mathematical Society
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    • v.34 no.4
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    • pp.1019-1028
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    • 1997
  • The integral solution for a deterministic evolution equation was introduced by Benilan. Similarly, in this paper, we define the integral solution for a stochastic evolution equation with a state-dependent diffusion term and prove that there exists a unique integral solution of the stochastic evolution euation under some conditions for the coefficients. Moreover we prove that this solution is a unique strong solution.

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The Effects of Electrodeposited Lead Dioxide Structure on the Ozone Evolution (전착이산화납 결정구조가 전해에 의한 오존발생에 미치는 영향)

  • Kim, In Hwan;Lee, Choong Young;Nam, Chong Woo
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.280-288
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    • 1996
  • In the ozone evolution using $PbO_2$, which was electrodeposited on Ti plate at various conditions in electrolyte, the effects of lead dioxide structure on the current efficiency and surface structure changes of lead dioxide were investigated. Also the effects of oxygen transfer reaction on the ozone evolution were investigated by means of a $PbO_2$ electrodeposited on the platinum rotating disk electrode. In order to develope an electrode for ozone evolution, durability of lead dioxide and optimum current density were investigated. At the electrodeposited lead dioxide with the larger grain size and higher crystallinity, the efficiency for ozone evolution was higher. Optimum current density to electrodeposite lead dioxide with large grain size and high crystalinity was $50mA/cm^2$. Lead dioxide deposited in the presence of glycerin showed the best advantage of ozone evolution. Also lead dioxide electrodeposited at less than $10mA/cm^2$ or at more than $100mA/cm^2$ has poor performance of ozone evolution and poor adhesive strength to substrate. In the beginning of ozone evolution, surface structure of lead dioxide was changed and this change resulted in good effects on ozone evolution. Lead dioxide doped with other elements was favorable not to ozone evolution but to oxygen evolution, so it is speculated that ozone evolution has not intermediate stage of oxygen evolution and occurs competitively with oxygen evolution. When ozone was evolved at $0.7{\sim}0.8A/cm^2$, the current efficiency was highest.

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A Comparative Study of Korean and United States College Students' Degree of Religiosity, Evolutionary Interest, Understanding and Acceptance and Their Structures (한국과 미국 대학생들의 종교성, 진화 흥미, 진화 개념, 진화 수용의 수준과 구조 비교)

  • Ha, Minsu;Cha, Heeyoung;Ku, Seulae
    • Journal of The Korean Association For Science Education
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    • v.32 no.10
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    • pp.1537-1550
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    • 2012
  • This study aims to explore the differences between Korean and United States college students regarding their degree of religiosity, interest in, understanding and acceptance of evolution, and the effects of their interaction on these variables. A total of one thousand and fifteen Korean and US biology majors and non-majors college students participated in this study and a sub sample of 516 students were randomly selected for statistical tests. The results illustrated that Korean college students harbored significantly lower degrees of religiosity and interest in evolution but significantly higher degrees of knowledge and acceptance of evolution than US college students. The path analysis uncovered that the knowledge of and interest in evolution played a mediating role between religiosity and acceptance of evolution. Korean college students' interest in evolution was less correlated to other variables than US college students' interest. The acceptance of evolution was less predicted by knowledge of evolution in the Korean biology major sample than in the US biology major sample. The acceptance of evolution was predicted more by religiosity in the Korean non-major sample than in US non-major sample. This study suggests that future Korean science curriculum for evolution needs to enhance the degree of students' interest in evolution. In addition, future Korean science curriculum needs an instructional strategy in developing students' ability to make scientific decisions, such as the acceptance of evolution, without interference from their personal religious belief.