• 제목/요약/키워드: Darkness

검색결과 390건 처리시간 0.025초

발아중 빛에 의한 무 유식물의 자엽 Microbody의 활성 변화 (Effect of Light on Developmental Changes and Activities of Microbody in the Cotyledons of Radish Seedlings)

  • 박민철
    • Journal of Plant Biology
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    • 제29권4호
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    • pp.243-254
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    • 1986
  • The enzyme patterns and the food storage changes in radish (Raphanus sativus L. cv. Taewang) cotyledons during seedling development were studied. The radish seeds were germinated for 8 days at $25^{\circ}C$ under light (7, 000 lux) or dark condition. The lipid and protein contents per seed were 4.3 mg and 2.85 mg respectively. In 8-day-old light-grown seedling, the lipid and protein contents per cotyledon pair were 1.5 mg and 2.08 mg; in 8-day-old dark-grown seedling, they were 0.8 mg and 1.24 mg respectively. The heterotrophic phase of seedlings continued for 3 days after sowing and followed by autotrophic phase (3~6 day) and senescence phase (6~8 day). The food storage function decreased in response to time course. During heterotrophic phase, the activities of glyoxysomal enzymes (malate synthetase, isocitrate lyase, and catalase) were high at 2~3 day. Those patterns were somewhat more prominent in darkness. During the autotrophic phase, the activities of peroxysomal enzymes (glycolate oxidase and catalase) increased at 4~5 day.

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Spermidine이 배추 잎 원형절편의 노쇠과정에 미치는 효과 (Effects of Spermidine on the Senescence in Leaf Discs of Chinese Cabbage)

  • 신정림
    • Journal of Plant Biology
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    • 제31권2호
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    • pp.155-164
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    • 1988
  • The rapid senescence of detached Chinese cabbage leaf discs in darkness is first manifested by a sharp rise in malondialdehyde content (indicated by distruption of membrane structure), then by a rise in peroxidase activity and a decrease in catalase activity, and ultimately by chlorophyll degradation. These changes in parameters besides the catalase activity during senescence were delayed by application of spermidine. Especially, 10-4M spermidine almost completely arrested chlorophyll degradation after incubaton over 5 days. Spermidine reduced the amount of ethylene produced by senescing leaf discs. Additionally, it also reduced IAA-induced ethylene production. Calcium ion (1mM, 10mM) supplied together with the spermidine diminished the spermidine action, indicating probable involvement of an initial ionic attachment mechanism. These results suggest that spermidine can be used as an anti-senescence agent for plants and that this agent may stabilize membrane structure through interaction with the negatively charged loci on the membrane and exert the influence during senescence.

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Role of glutaredoxinl in culmination of Dictyostelium discoideum

  • Park, Chang-Hoon;Yim, Hyung-Soon;Kang, Sa-Ouk
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.60-60
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    • 2003
  • GSH-dependent glutaredoxinl (Grxl) was characterized in Dictyostelium discoideum. After starvation, the mRNA levels of grx1 gene increased during aggregation, thereafter decreased up to tip formation and increased again during culmination. To investigate the function of Grxl, the protein was overexpressed in D. discoideum using actinl5 promoter, The phenotype analysis on Grxl-overexpressed cells showed the maintenance of slug stage for a long period and delayed culmination under dark condition. To corroborate these phenotype by the enzyme, the two mutant forms of Grxl (C21S and C24S) were overexpressed in D. discoideum. The phenotype of two mutant cells represented no slug formation and the early culmination on dark condition. These results indicate that Grxl might regulate the transition from slug to culminant in darkness.

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Aipheus euphrosyne (새우아목, 딱총새우과)의 Zoea 유생 (Zoeal Stages of Aipheus euphrosyne richardsoni Yaldwyne, 1971 (Decapoda: Macrura: Alpheidae) Reared in the Laboratory)

  • 양회정;김창현
    • 한국동물학회지
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    • 제39권1호
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    • pp.106-114
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    • 1996
  • 실험실에서 사육된 Alpheus euplirosyne rlchardsoni의 zoea 유생을 기재 및 도시하였다. 사유은 수온 25$^{\circ}$C, 염분농도 33.3$\textperthousand$, 광주기 l4hr light: lOhr dark의 조건하에서 진행되었다. A. euplirosyne rlchardsoni는 부화직전의 난의크기와 제1기 zoea유생의 길이에서 장기발생(extended development)을 보였다. 딱총새우속에 속하는 6종의 제1기 zoea유생의 형태적인 특징에 대하여 논의하였다.

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광선의 영향에 따른 감자의 Chlorophyll과 Glycoalkaloid의 함량 변화 (The Changes of Chlorophyll and Glycoalkaloid Contents in Potato Tubers after Exposure of Fluorescent and UV Light)

  • 김정애;소궤신행;한재숙
    • 동아시아식생활학회지
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    • 제15권2호
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    • pp.207-212
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    • 2005
  • To determine changes of chlorophyll and potato glycoalkaloid(PGA) contents in potato tubers after lightening, Dejima potatoes cultivated in Korea were used and PGA was analyzed by HPLC. Potatoes were stored under fluorescent and UV light exposure or darkness for 7 days at $5^{\circ}C$. The contents of chlorophyll and glycoalkaloid in the peel of potatoes exposed to fluorescent light were increased to $84\%,\;69.5\%$ respectively compared to potatoes stored without lightening. While a marked effect of lightening on the peel of potatoes exposed to fluorescent light, UV light lead to no change of chlorophyll and less increase in glycoalkaloid than fluorescent did. The increase of chlorophyll was provoked by only fluorescent light. Cortex part did not accumulate any chlorophyll or glycoalkaloid.

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Fuzzy 추론 및 명암차이법을 이용한 카메라 줌, 포커스 자동 조절 시스템 (An Automatic Control System of a Camera Zoom and Focus Using the Fuzzy Inference and the Difference of the Light and Darkness)

  • 박홍선;박상욱;박정현;곽주원;손영선
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2002년도 추계학술대회 및 정기총회
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    • pp.406-409
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    • 2002
  • 본 논문에서는 문자인식이 가능하도록 줌, 포커스를 제어하여 한글 문서 영상을 확대/축소하는 시스템을 구현하였다. 한글 문서 영상에서 확대/축소 할 영역이 지정되면 그 영역의 가로, 세로 거리를 펄스 수로 변환한 후 Step모터를 제어하여 그 위치만큼 카메라를 이동시킨다. 문서 영상이 입력되면 문자인식이 가능한 크기만큼 줌을 제어하고, 피드백 되어진 영상으로부터 조정된 줌에 맞는 포커스로 근접 제어한 후, 더욱 선명한 영상을 얻기 위해 명암 차이에 의한 미세 조정을 하였다. 이 경우, 줌 및 포커스는 퍼지 추론으로 .제어하는 DC모터로 조정하였다.

제주시 도로조명 실태조사 및 모델링 (Modeling and Actual Investigation of Roadway Lighting in Jejusi)

  • 이상근;오성보;김덕구
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 학술대회 논문집
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    • pp.147-150
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    • 2005
  • Fixed lighting of public ways for both vehicles and pedestrians can create a nighttime environment in which people see comfortably and can quickly and accurately identify objects on the roadway being travelled roadway lighting can improve traffic safety, achieve efficient traffic movement and promote the general use of the facility during darkness. The design of a roadway lighting system involves consideration of visibility, economics, esthetics, safety and environmental conditions. This paper describe estimation of horizontal illuminance by actual measurement at main streets in Jejusi. We try to evaluate Jejusi Roadway Lighting Conditions for modeling by computer simulation.

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퍼지노리를 이용한 Bin-Picking방법 (A Fuzzy Logic Based Bin-Picking Technique)

  • 김태원;서일홍
    • 대한전기학회논문지
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    • 제41권8호
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    • pp.938-946
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    • 1992
  • A novel 2-dimensional matched filter of the parallel-jaw type using fuzzy logic is proposed for bin picking. Specifically, the averaged pixel intensity of the windowed region for the filtering is considered to be fuzzy. Also membership functions for darkness and brightness are designed by employing the intensity histogram of the image. Then a rule is given to know how much a windowed region can be a possible holdsite. Furthermore eight rules are made to determine the part orientation, where Mamdani's reasoning method is applied. The proposed technique shows better performances than that of the conventional matched filtering technique in the following senses` 1) most of holdsites determined by the proposed technique are not concentrated at the locations nearly the end of part and 2) our filter is rather insensitive to noises than the conventional method. To show the validities of our proposed technique, some experimental results are illustrated and compared with the results by conventional matched filter technique.

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웨이브렛 변환과 편광 필터를 이용한 차량번호판 축출 (Vehicle Plate Extraction Using Wavelet Transform and Polarized Light Filter)

  • 김옥규;이창윤;황형덕;강혜진;박영식
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2003년도 하계학술대회 논문집
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    • pp.102-105
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    • 2003
  • Up to the present studies of the car number recognition system, it is generally known to have serious problems such as relatively long processing time due to the excessive length of data extracted from the number plate based on the current image characteristics, and the image blurring with the physical damage of the brightness and darkness signals of the number plate caused by external impulses with many difficulties in the extraction of the highlighted numbers. In this Paper we used the characteristics firstly having a constant brightness of number plate, and a high density to the horizontal axis, and the influences of highlighted signal could be reduced by making reflections less through the polarized filter on the camera for any highlighted signal. For the more, the data processing time and the noise reduction are effectively implemented by using the wavelet transform of time-space scale with the considerations on the physical loss and processing time.

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Saanen 젖염소에서 발생한 Pasteurella multocida에 의한 유방염 예 (A Case of Mastitis Infected with Pasteurella multocida in Saanen Dairy Goat)

  • 이채용;이정치;선재승;이윤경;박하연;김영철
    • 한국임상수의학회지
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    • 제24권3호
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    • pp.476-478
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    • 2007
  • A 3-years-old female Saanen dairy goat was admitted to the Teaching Animal Hospital at Chonnam National University with clinical signs of poor appetites, reddish darkness udder and bloody milk. She died one day after hospitalization, and Pasteurella multocida was isolated from the mammary gland and was confirmed by the PCR assay using a P. multocida-specific primer set. To our knowledge, this is the first case report of mastitis caused by P. multocida in Saanen dairy goat in Korea.