• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2002년도 심포지엄
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• pp.98-98
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• 2002

In higher dicotyledonous plants, the floral organs are arranged in four different whorls, containing sepals, stamens and carpels. petals, stamens and carpels. The specification of floral organ identity is explained by the ABC model (Weigel and Meyerowitz 1994). expression of an A-function gene specifies sepal formation in whorl 1. the combination of A-and B-function genes specifies the formation of petals in whorl 2, B-and C-function genes spesify stamen formation in whorl 3, and expression of the C-function alone determines the formation of carpels in whorl 1. A-, B-, C-function genes have been isolated from many plant species and most of them belong to the family of MADS-box genes encoding transcription factor. In contrast to the flower of higher dicots, the perianths of genseng plants have three whorls of almost identical petaloid organs. van Tunen et al. (1993) proposed a modified ABC model, exemplified with tulip. In this model, B-function genes are expressed in whorl 1 as well as whorl 2 and 3, theefore the organs of whorl 1 and whorl 2 have the same petaloid structure. They proposed this model with the molphological data of wild type and mutant flowers of tulip, however, there are no molecular data. To date, B-function genes were isolated several grass plants, rice, wheat and maize. However, grass plants have highly derived flowers, without well-developed perianths. To find out how the ABC model has to be modified for the Genseng plants, we have cloned and characterized orthologs of A-, B-, C-function genes from genseng.

• 과학교육연구지
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• 제36권1호
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• pp.35-48
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• 2012

이 연구에서는 2007 개정 교육과정에 따른 중학교 과학 1 교과서 '식물의 영양' 단원의 탐구활동과 이와 관련되는 제7차 교육과정에 따른 중학교 과학 2 교과서 '식물의 구조와 기능' 단원의 탐구활동을 탐구 내용 영역, 탐구 과정 영역, 탐구 상황 영역의 3차원 분석틀을 이용하여 분석하였다. '식물의 영양' 단원의 평균 탐구활동의 수는 9.2개로 '식물의 구조와 기능' 단원의 경우보다 3.8개 줄었다. 그리고 두 단원에서 공통적으로 다루는 주제도 있는 반면, 교육과정 개정에 따른 내용의 변화를 반영하여 중점을 두는 탐구활동 주제가 달라진 경우도 있었다. 두 단원 모두 기초 탐구 과정에서는 '관찰', 통합 탐구 과정에서는 '자료해석'의 비율이 높았고, '실험관찰'에 해당되는 비율이 매우 높게 나타났으며, '순수과학적 상황'의 비율이 높게 나타났다. '식물의 영양' 단원에서는 기초 탐구 요소보다 통합 탐구 요소를 더 많이 다루고 있고, '해보기'에 해당하는 탐구활동 수가 증가하고 '모의활동'이 제시된 점이 특징적이며, '개인적 상황'의 비율이 늘었고 '기술적 상황'과 '자연환경적 상황'이 제시된 탐구활동도 나타났다. 중학교 과학 교과서 개발 시 탐구활동이 보다 다양해지도록 탐구활동의 내용, 탐구 과정, 유형, 상황 등의 측면을 고려해야 할 것이다.

• The Plant Pathology Journal
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• 제38권6호
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• pp.583-592
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• 2022

Root-knot nematode disease is a widespread and catastrophic disease of tobacco. However, little is known about the relationship between rhizosphere bacterial community and root-knot nematode disease. This study used 16S rRNA gene sequencing and PICRUSt to assess bacterial community structure and function changes in rhizosphere soil from Meloidogyne incognita-infected tobacco plants. We studied the rhizosphere bacterial community structure of M. incognita-infected and uninfected tobacco plants through a paired comparison design in two regions of tobacco planting area, Yuxi and Jiuxiang of Yunnan Province, southwest China. According to the findings, M. incognita infection can alter the bacterial population in the soil. Uninfested soil has more operational taxonomic unit numbers and richness than infested soil. Principal Coordinate Analysis revealed clear separations between bacterial communities from infested and uninfested soil, indicating that different infection conditions resulted in significantly different bacterial community structures in soils. Firmicutes was prevalent in infested soil, but Chloroflexi and Acidobacteria were prevalent in uninfested soil. Sphingomonas, Streptomyces, and Bradyrhizobium were the dominant bacteria genera, and their abundance were higher in infested soil. By PICRUSt analysis, some metabolism-related functions and signal transduction functions of the rhizosphere bacterial community in the M. incognita infection-tobacco plants had a higher relative abundance than those uninfected. As a result, rhizosphere soils from tobacco plants infected with M. incognita showed considerable bacterial community structure and function alterations.

• 한국초등과학교육학회지:초등과학교육
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• 제21권1호
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• pp.13-24
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• 2002

This study examined the knowledge structure constructed by children before formal instruction, and successive changes in the structural complexity of knowledge during the learning of the 'Structure and Function of Plants' unit. The researchers let the 5th graders draw the first draft of their concept maps in order to examine the pre-existing knowledge structure concerned with the unit and also four concept maps after completing every fourth lesson. Each concept map drawn by children on the basis of the previous one showed the degree of their current understanding on the structure and function of plants. The results revealed that only two levels of hierarchy and five relationships among the components of the first concept map(relationship, hierarchy, cross link and example) were proven to be valid in terms of conceptual relevance. According to the standard map, there was no change in hierarchy from the 2nd to the 3rd map, and in example from the 2nd to the 4th map. However, the gradual and successive increases of the scores in all components appeared in the children's maps throughout the unit. Knowledge restructuring occurred strongly in the early periods from the 1st to the 6th lesson, and the significant stable changes in tuning and accretion appeared throughout the whole lessons. The results also showed that there were no significant gender differences on the 5th grader's knowledge structuring.

• 전자공학회논문지
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• 제52권7호
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• pp.127-134
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• 2015

본 연구에서는 다입출력 불확실 선형 플랜트를 위한 포화함수에 의한 연속 슬라이딩 면 변환 가변 구조 시스템이 주어진다. 이론적으로 불연속 슬라이딩 면 변환 가변구조 시스템을 제안한다. 사전에 결정된 슬라이딩 면 위에 슬라이딩 모드의 다입출력 존재 조건과 함께 페루프 지수 안정성에 대해 검토한다. 실제 응용을 위하여 포화 함수에 의하여 불연속 가변구조 시스템의 연속 근사화를 이룬다. 실제적인 관점에서 가변 구조 시스템의 내부 특성인 제어입력의 불연속성을 많이 개선한다, 설계 예와 시뮬레이션 연구를 통하여 제안된 연속 변환 가변구조 시스템 제어기의 유용성을 입증한다.

• BMB Reports
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• 제33권3호
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• pp.195-201
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• 2000

A human gene has been reported that may encode the enzyme acetohydroxyacid synthase. Previously this enzyme was thought to be absent from animals although it is present in plants and many microorganisms. In plants, this enzyme is the target of a number of commercial herbicides and the use of these compounds may need to be reassessed if the human enzyme exists and proves to be susceptible to inhibition. Here we report the construction of several plasmid vectors containing the cDNA sequence for this protein, and their expression in Escherichia coli. High levels of expression were observed, but most of the protein proved to be insoluble. The small amounts of soluble protein contained little or no acetohydroxyacid synthase activity. Attempts to refold the insoluble protein were successful insofar as the protein became soluble. However, the refolded protein did not gain any acetohydroxyacid synthase activity. In vivo complementation tests of an E. coli mutant produced no evidence that the protein is active. Incorrect folding, or the lack of another subunit, may explain the data but we favor the interpretation that this gene does not encode an acetohydroxyacid synthase.

• 전자공학회논문지CI
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• 제49권2호
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• pp.115-122
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• 2012

본 논문에서는 CosGauss라고 하는 코사인함수로 모듈화 된 가우시안 활성화함수가 뉴로 네트워크에서 다항식과 계단함수의 근사에 사용될 수 있음을 증명한다. CosGauss 함수는 시그모이드, 하이퍼볼릭 탄젠트, 가우시안 활성화 함수보다 더 많은 범프(bump)를 구성 할 수 있다. 이 함수를 캐스케이드 코릴레이션 뉴로 네트워크 학습에 사용하여 벤치마크 문제인 Tic-Tac-Toe 게임과 아이리스(iris) 식물 문제와 실험하고 여기에서 얻어진 결과를 다른 활성화 함수를 사용한 결과와 비교 분석한다.

• 한국조경학회지
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• 제33권2호
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• pp.48-59
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• 2005

The purpose of this study was to examine the ecological characteristics of herbaceous communities by systematic and scientific analysis of their structure and diversity in the Midongsan Arboretum and to offer raw data for a long-tenn monitoring study. The importance value and diversity index of species appearing in twenty plots from July to September, 2004 were analyzed and a management plan for these communities is presented. Vascular plants were represented by 60 taxa of 23 families, 51 genera, 50 species and 10 varieties. Based on the results of importance value analysis, the most dominant species was Artemisia princeps var. orientalis, followed by Setaria viridis and Erigeron canadensis. The diversity index analysis showed that plot no. 5 had the highest H' and H'_{max}$(2.0135 and 2.6391). It's species composition was comparatively more diverse and it's structure more stable than other plots. Artemisia montana and Dactylis glomerata showed the highest correlation between species. Because herbaceous communities are important biological habitats and provide important function in environmental conservation, it is important to properly preserve these communities. At the same time, in order to preserve genetic resources and improve spatial function, it may be necessary to consider removing herbaceous communities in certain areas. In the future, the relations between physicochemical soil properties and herbaceous communities should be examined and community movement should be studied.

• ALGAE
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• 제18권4호
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• pp.295-299
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• 2003

The population dynamics of Ecklonia stolonifera was investigated at Tongyeong coastal area in the South Sea of Korea. The blade length and width, stipe length and diameter, mean total length and mean weight were measured from randomly collected fifty individuals in every month. The plants in Tongyeong population were relatively bigger than those of Busan Korea and Aomori Japan in terms of their blade length and width. The population biomass was low in winter and high in spring and summer. The sporangial sori were found from August to December but prominent in September and October. About 90 % of the Tongyeong population was consisted of one- and two-year old plants and the zoosporangial sori were observed mostly in two-year old plants. It was different from the results of Busan and Aomori population in which the zoosporangial sori were observed from the plants older than three years. The new populations were developed from the zoospores of two-year old plants and their generation time was relatively shorter than those of Busan and Aomori.

• International Journal of Industrial Entomology and Biomaterials
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• 제29권1호
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• pp.93-119
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• 2014

Tropical tasar silkworm, Antheraea mylitta (Lepidoptera: Saturniidae) is a polyphagous silk producing forest silkworm of commercial importance in India. Forest dependent people rear its larvae on different forestry host plants twice or thrice in a year for small household income. Larvae of A. mylitta feeds on many forest tree species, but always show a great degree of selectivity as a function of its behavioural responses to physical structure and chemical features of the host plants. Cocoon crop of A. mylitta is influenced by heterogeneity of tasar food plants and climatic conditions of the habitat. The role of host plants, temperature, humidity, rainfall, photoperiod and climatic variables on the growth and development of insects have clearly been demonstrated. This article entails an in-depth analysis on ecological and nutritional aspects of A. mylitta, which may provide selective information to researcher and forest managers, who are particularly associated with livelihood improvement of the poor people in forested area through location specific forest insect industry.