• Title/Summary/Keyword: Leaf mode

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Ultrastructure of the Rust Fungus Puccinia miscanthi in the Teliospore Stage Interacting with the Biofuel Plant Miscanthus sinensis

  • Kim, Ki Woo
    • The Plant Pathology Journal
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    • v.31 no.3
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    • pp.299-304
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    • 2015
  • Interaction of the the rust fungus Puccinia miscanthi with the biofuel plant Miscanthus sinensis during the teliospore phase was investigated by light and electron microscopy. P. miscanthi telia were oval-shaped and present on both the adaxial and abaxial leaf surfaces. Teliospores were brown, one-septate (two-celled), and had pedicels attached to one end. Transmission electron microscopy revealed numerous electron-translucent lipid globules in the cytoplasm of teliospores. Extensive cell wall dissolution around hyphae was not observed in the host tissues beneath the telia. Hyphae were found between mesophyll cells in the leaf tissues as well as in host cells. Intracellular hyphae, possibly haustoria, possessed electron-dense fungal cell walls encased by an electron-transparent fibrillar extrahaustorial sheath that had an electron-dense extrahaustorial membrane. The infected host cells appeared to maintain their membrane-bound structures such as nuclei and chloroplasts. These results suggest that the rust fungus maintains its biotrophic phase with most mesophyll cells of M. sinensis. Such a nutritional mode would permit the rust fungus to obtain food reserves for transient growth in the course of host alteration.

Distribution of Aucuba japonica in two contrasting geobotanical regions of Japan: An analysis of adaptation mode

  • Ali, Md. Sohrab;Kikuzawa, Kihachiro
    • Journal of Ecology and Environment
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    • v.36 no.3
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    • pp.173-181
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    • 2013
  • Two varieties of Aucuba japonica differ in ways that can be considered adaptive to differing geo-climatic conditions in their respective distribution ranges. Irrespective of growth stage, the mean leaf size of A. japonica var. japonica was significantly larger than A. japonica var. borealis. Smaller leaf size and ultimately smaller stature of A. japonica var. borealis are an advantage under the higher snow load and lower temperatures in the forests along the East Sea where the variety grows. Snow load also acted as an important driving force for structural modifications of A. japonica var. borealis from cellular level in leaves to the organization of branch extension growth. Global warming by changing snowfall patterns in Japan may lead to range shifts in the two varieties of A. japonica.

GENETIC ANALYSIS OF QUANTITATIVE CHARACTERS IN $F_2$ POPULATIONS OF KOREA LOCAL AND ORIENTAL TOBACCO VARIETIES (N. TABACUM L.) (재래종과 Orient종 연초 $F_2$세대의 양적 형질에 대한 유전분석)

  • 이정덕;장권열
    • Journal of the Korean Society of Tobacco Science
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    • v.6 no.2
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    • pp.207-214
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    • 1984
  • In order to obtain the basic information for the successful breeding of aromatic tobacco (N. tabacum L.), the combining ability and the mode of inheritance in 28 $F_2$ hybrids by diallel crosses between Korea local and oriental varieties were investigated. Estimates of general combining ability were significant for all characters investigated, and the specific combining ability was significant for stalk height, leaves per plant, leaf length, leaf width and days to flower. The partial dominance was exhibited by all characters investigated as well as additive effects were larger than dominance effects for all characters.

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A Study on the Construction of MVCT Dose Calculation Model by Using Dosimetry Check™ (Dosimetry Check™를 이용한 MVCT 선량계산 모델 구축에 관한 연구)

  • Um, Ki-Cheon;Kim, Chang-Hwan;Jeon, Soo-Dong;Back, Geum-Mun
    • Journal of radiological science and technology
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    • v.43 no.6
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    • pp.431-441
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    • 2020
  • The purpose of this study was to construct a model of MVCT(Megavoltage Computed Tomography) dose calculation by using Dosimetry Check™, a program that radiation treatment dose verification, and establish a protocol that can be accumulated to the radiation treatment dose distribution. We acquired sinogram of MVCT after air scan in Fine, Normal, Coarse mode. Dosimetry Check™(DC) program can analyze only DICOM(Digital Imaging Communications in Medicine) format, however acquired sinogram is dat format. Thus, we made MVCT RC-DICOM format by using acquired sinogram. In addition, we made MVCT RP-DICOM by using principle of generating MLC(Multi-leaf Collimator) control points at half location of pitch in treatment RP-DICOM. The MVCT imaging dose in fine mode was measured by using ionization chamber, and normalized to the MVCT dose calculation model, the MVCT imaging dose of Normal, Coarse mode was calculated by using DC program. As a results, 2.08 cGy was measured by using ionization chamber in Fine mode and normalized based on the measured dose in DC program. After normalization, the result of MVCT dose calculation in Normal, Coarse mode, each mode was calculated 0.957, 0.621 cGy. Finally, the dose resulting from the process for acquisition of MVCT can be accumulated to the treatment dose distribution for dose evaluation. It is believed that this could be contribute clinically to a more realistic dose evaluation. From now on, it is considered that it will be able to provide more accurate and realistic dose information in radiation therapy planning evaluation by using Tomotherapy.

Mode of Resistance and/or Tolerance Action of Paraquat (Paraquat 저항성(抵抗性) 및 내성(耐性) 발현(發現) 기구(機構))

  • Ma, Sang-Yong;Chun, Jae-Chul
    • Korean Journal of Environmental Agriculture
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    • v.13 no.3
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    • pp.373-385
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    • 1994
  • Resistance to paraquat (1,1'-dimethyl-4,4'-bipyridilium ion) has developed in 12 species of 8 genera to which paraquat has been applied 6 to 10 times per year for 5 or more years. In recent years, tolerance to paraquat has been found in Rehmannia glutinosa (Gaertn.) Liboch. ex Fisch. & Mey. which has never been applied with any herbicides involving paraquat. In this review, we differentiate the terms, resistance and tolerance, on the basis of the paraquat-exposure history. Five hypotheses have been evaluated in several species as potential mechanisms of paraquat resistance and/or tolerance. In a species, the mode of action may be due to 1) reduced quantities of paraquat absorbed through the leaf surface, 2) detoxification of paraquat caused by the enhanced paraquat-metabolic activity, 3) rapid sequestration reducing level of paraquat at the site of action in chloroplast, 4) alteration of site of action in photosystem I resulting in interruption of electron transport to paraquat, and 5) rapid enzymatic detoxification of superoxide and other toxic forms of oxygen.

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Quantitative Analysis of Wear Debris for Surface Modification Layer by Ferrography (Ferrography에 의한 표면개질층의 마모분 정량분석)

  • 오성모;이봉구
    • Tribology and Lubricants
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    • v.15 no.3
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    • pp.265-271
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    • 1999
  • Wherever there are rotating equipment and contact between surface, there is wear and the generation of wear particles. The particles contained in the lubricating oil carry detailed and important information about the condition monitoring of the machine. This information may be deduced from particle shape, composition, size distribution, and concentration. Therefore, This paper was undertaken to Ferrography system of wear debris generated from lubricated moving machine surface. The lubricating wear test was performed under different experimental conditions using the Falex wear test of Pin and V-Block type by Ti(C, N) coated. It was shown from the test results that wear particle concentration (WPC) and wear severity Index( $I_{S}$), size distribution in normal and abnormal wear have come out all the higher value by increases sliding friction time. Wear shape is observed on the Ferrogram it was discovered a thin leaf wear debris as well as ball and plate type wear particles. This kind of large wear shape have an important effect not only metals damage, but also seizure phenomenon.

Ferrography에 의한 마멸분 정량분석

  • O, Seong-Mo;Lee, Bong-Gu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.10 s.181
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    • pp.2420-2427
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    • 2000
  • In contacting between surface, there is wear and the generation of wear particles. The particles contained in the lubricating oil carry detailed and important information about the condition monitoring of the machine. Therefore, This paper was undertaken for Ferrography system of wear debris generated from lubricated moving machine surface. The lubricating wear test was performed under different experimental conditions using the Falex wear test of Pin and V-Block type by Ti(C,N) coated. It was shown from the test results that wear particle concentration(WPC) ; wear severity Index(IS) and size\distribution have come out all the higher value by increases sliding friction time. By the Ferrogram a thin leaf wear debris as well as ball and plate type wear particles was observed.

Genetics, Agronomic, and Molecular Study of Leaflet Mutants in Mungbean(Vigna radiata(L.) Wilczek)

  • Soehendi, Rudy;Chanprame, Sontichai;Toojinda, Theerayut;Ngampongsai, Sumana;Srinives, Peerasak
    • Journal of Crop Science and Biotechnology
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    • v.10 no.3
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    • pp.193-200
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    • 2007
  • Mungbean plants generally have a relatively close canopy, thus a large amount of self-shading can reduce yield due to poor light penetration. Modification of leaflet type can affect leaf canopy and could alter seed yield. Two multiple leaflet mutants were obtained from gamma-ray irradiation and used to study the mode of inheritance related to leaflet types and to evaluate their agronomic features. The cross between large-heptafoliate leaflet with small-pentafoliate leaflet mutants produce all $F_1$ plants with normal trifoliate leaflets. The $F_2$ plants segregated in leaflet size and leaflet number into a 9:3:3:1 ratio of large-trifoliate: large-heptafoliate: small-pentafoliate: small-heptafoliate plants, suggesting that independent loci control leaflet size and leaflet number. Regarding leaflet number, the $F_2$ population can be classified into normal-trifoliate, small-pentafoliate, large-heptafoliate, and small-heptafoliate at the dihybrid ratio of 9:3:3:1. The gene symbols $N_1,n_1$ and $N_2,n_2$ are proposed to represent leaflet number. Since no plant was found with large-pentafoliate leaflets, we hypothesize that the $N_2$ allele expresses pleiotropic effect on both leaflet number and leaflet size. Another possibility is that an additional locus with S and s alleles controls leaflet size and S is tightly linked with $N_2$. The effect of multifoliate leaflet on yield and yield components was evaluated in four mungbean families each with four leaflet isolines under three environments. Averaging across the families and environments, the normal-trifoliate and large-heptafoliate lines gave higher yield than small pentafoliate and heptafoliate ones. These two large leaflet lines also had higher leaf area per plant than the other multifoliate lines. Therefore, the mungbean lines with a greater leaf area, which were likely to intercept more sunlight, gave greater yield. Three AFLP markers that were found to be linked to number of leaflets per leaf, corresponded to the N1 allele of the smallpentafoliate parent.

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Shoot.Root Growth and Nodule Formation of White Clover as Affected by Removal of Cotyledon and Unifoliolate (자엽 및 단엽 제법에 따른 White Clover 지상부 및 지하부 생장과 근류유형)

  • 강진호;한경수;박진서;이희원
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.14 no.3
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    • pp.177-185
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    • 1994
  • Slow seedling growth rate and nodulation failure of white clover (Trifolium repens L.) has been limited its good establishment to pastures. The experiment was done to determine the effect of removal of cotyledon and unifoliolate on the shoot, root growth, and nodule formation of 4 white clover cultivars for 8 weeks after the treatment. Four white clover cv. Regal (large leaf), Louisiana S-I (medium-large leaf), Grasslands Huia (mediumsmall leaf), and Aberystwyth S184 (small leaf), were grown in IOcm plastic pot containing 2:l:l soi1:sand:peat moss mixture until grown to cotyledon or unifoliolate stage and then removed one (Cl) or two cotyledons (C2) at cotyledon stage, and unifoliolate only (U), unifoliolate and one cotyledon (UCl) or unifoliolate and two cotyledons (UC2) at the unifoliolate stage, and the plants were sampled at 4, 6 and 8 weeks after the treatments. The intact plants had greater shoot and root dry weights, and no. of nodules than removal-treated ones. Removal treatments at cotyledon stage, the dry weight and no. of nodules more decreased in C1 and C2 than that of unifoliolate stage. While the severer cotyledon removal, the more reduction. Although the dry weights and no. of nodules steadily inclined with regrowing period, the former were higher in Regal and La. S-1 than in the others since 6 weeks after removal treatment but the latter was more in S 184 than in the others 8 weeks after removal treatment. Relationship between no. of nodules and shoot or root dry weight was analysed as linear mode while the earlier and severe removal, the steeper slope. It was concluded that severer damage of cotyledon and unifoliolate had detrimental effects on the shoot and root growth, nodule formation, and aftermath establishment of white clover.

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Design and control of a proof-of-concept active jet engine intake using shape memory alloy actuators

  • Song, Gangbing;Ma, Ning;Li, Luyu;Penney, Nick;Barr, Todd;Lee, Ho-Jun;Arnold, Steve
    • Smart Structures and Systems
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    • v.7 no.1
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    • pp.1-13
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    • 2011
  • It has been shown in the literature that active adjustment of the intake area of a jet engine has potential to improve its fuel efficiency. This paper presents the design and control of a novel proof-of-concept active jet engine intake using Nickel-Titanium (Ni-Ti or Nitinol) shape memory alloy (SMA) wire actuators. The Nitinol SMA material is used in this research due to its advantages of high power-to-weight ratio and electrical resistive actuation. The Nitinol SMA material can be fabricated into a variety of shapes, such as strips, foils, rods and wires. In this paper, SMA wires are used due to its ability to generate a large strain: up to 6% for repeated operations. The proposed proof-of-concept engine intake employs overlapping leaves in a concentric configuration. Each leaf is mounted on a supporting bar than can rotate. The supporting bars are actuated by an SMA wire actuator in a ring configuration. Electrical resistive heating is used to actuate the SMA wire actuator and rotate the supporting bars. To enable feedback control, a laser range sensor is used to detect the movement of a leaf and therefore the radius of the intake area. Due to the hysteresis, an inherent nonlinear phenomenon associated with SMAs, a nonlinear robust controller is used to control the SMA actuators. The control design uses the sliding-mode approach and can compensate the nonlinearities associated with the SMA actuator. A proof-of-concept model is fabricated and its feedback control experiments show that the intake area can be precisely controlled using the SMA wire actuator and has the ability to reduce the area up to 25%. The experiments demonstrate the feasibility of engine intake area control using an SMA wire actuator under the proposed design.