• Title/Summary/Keyword: ferns

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e-Navigation Committee - A new Paradigm

  • Guk, Seung-Gi
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.354-356
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    • 2007
  • IALA의 e-Navigation Committee에서 논의 되고 있는 국제적인 동향 및 움직임에 대하여 기술한다. 특히 e-Navigation에 대한 개념, 비전 등을 알아보고 향후 전망에 대하여 논의한다.

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Extracts from Polypodium ferns upregulate the expression of CD95 in human peripheral blood lymphocytes

  • Lombardi, Valter R.M.;Etcheverria, I.;Fernandez-Novoa, L.;Blanco, A.;Diaz, J.;Cacabelos, R.
    • Advances in Traditional Medicine
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    • v.3 no.2
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    • pp.90-99
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    • 2003
  • There are several data in the literature indicating a great variety of pharmacological activities of Polypodium genus, which exhibit antiinflammatory and immunomodulatory activities. Since one of our main interests is to obtain natural immunoregulatory agents devoid of pharmacological adverse effects, we used flow cytometry analysis to highlight relative contributions of a water-soluble fraction of different concentrations of Polypodium rhizome extracts on lymphocyte subpopulations, NK and LAK activity. To measure their potential immunoregulatory activity a T cell proliferation assay in response to phytohemaglutinin (PHA) and mixed lymphocyte reactions were chosen. As a confirmatory bioassay we studied the effect of our extracts on CD45RO and CD95 antigen expressions. The results indicate that CD95 expression dramatically increases after peripheral blood lymphocyte activation and treatment with Polypodium leucotomus, cambricum and vulgare extracts, suggesting a powerful intrinsic pro-apoptotic effect.

Morphological Characteristics and Conceptualization of Guard Cells in Differernt Plants (식물에 따른 공변세포의 형태적 특징과 개념화)

  • Lee, Joon-Sang;Park, Chan-Hee
    • Journal of Environmental Science International
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    • v.25 no.9
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    • pp.1289-1297
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    • 2016
  • The walls of guard cells have many specialized features. Guard cells are present in the leaves of bryophytes, ferns, and almost all vascular plants. However, they exhibit considerable morphological diversities. There are two types of guard cells: the first type is found in a few monocots, such as palms and corn, and the other is found in most dicots, many monocots, mosses, ferns, and gymnosperms. In corns, guard cells have a characteristic dumbbell shape with bulbous ends. Most dicot and monocot species have kidney-shaped guard cells that have an elliptical contour with a pore at its center. Although subsidiary cells are common in species with kidney-shaped stomata, they are almost always absent in most of the other plants. In this study, there were many different stomatal features that were associated with kidney-shaped guard cells, but not dumbbell shaped guard cells, which are present in most grasses, such as cereals. Each plant investigated exhibited different characteristic features and most of these plants had kidney-shaped guard cells. However, the guard cells of Chamaesyce supina Mold, were often more rectangular than kidney-shaped. In contrast, Sedum sarmentosum guard cells were of the sink ensiform type and in Trifolium repens, the guard cells exhibited a more rhombic shape. Therefore, kidney-shaped guard cells could be divided into a number of subtypes that need to be investigated further.

A short record for the distribution of two rare Korean ferns (한반도 희귀양치식물 2종의 신분포지 보고)

  • Sun, Eun-Mi;Jang, Jeong-Won;Im, Hyoung-Tak;Son, Hyun-Deok
    • Korean Journal of Plant Taxonomy
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    • v.42 no.2
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    • pp.167-170
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    • 2012
  • During the course of the execution of the project entitled Distribution Research of Rare Plants, we found the habitats of two rare ferns with obscure and/or extremely restricted distribution ranges, as previously unreported habitats. A subantarctic fern reported on Hamgyeong-do and Gangwon-do, Dryopteris coreano-montana Nakai, was found on Mt. Ibam in Jangseong-gun, Jeollanam-do. A subtropical fern reported south of Jeju-do, Dryopteris decipiens (Hook.) Kuntze, was newly found on Mt. Cheongwan of Jangheung-gun in Jeollanam-do.

New records of ferns in the flora of Laos (1) (라오스 미기록 양치식물 (1))

  • Hwang, In Chun;Moon, Myung-Ok;Bounphanmy, Somchanh;Yoon, Narae;Sun, Byung-Yun
    • Korean Journal of Plant Taxonomy
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    • v.45 no.2
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    • pp.109-113
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    • 2015
  • Fieldwork in Lao PDR during 2007-2008 resulted in the discovery of 15 unrecorded fern species among the flora of Lao PDR. All have been identified in other countries in southeastern Asia, as well as from other tropical areas. The species are as follows: Asplenicaceae (Asplenium delavayi, A. rockier), Athyriaceae (Anisocampium cuspidatum), Dennstaedtiaceae (Microlepia hookeriana, Pteridium revolutum), Dryopteridaceae (Didymochlaena truncatula, Dryopteris cochleata, Polystichum biaristatum, P. lindsaefolium), Gleicheniaceae (Dicranopteris curranii), Hypodematiaceae (Hypodematium crenatum), Lindsaeaceae (Lindsaea heterophylla), Pteridaceae (Pteris decrescens), Polypodiaceae (Pyrrosia nummularifolia) and Thelypteridaceae (Cyclosorus dentatus).

Effect of Silicon on Growth and Temperature Stress Tolerance of Nephrolepis exaltata 'Corditas'

  • Sivanesan, Iyyakkannu;Son, Moon Sook;Soundararajan, Prabhakaran;Jeong, Byoung Ryong
    • Horticultural Science & Technology
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    • v.32 no.2
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    • pp.142-148
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    • 2014
  • Effect of silicon (Si) nutrition on growth and temperature stress tolerance of Nephrolepis exaltata 'Corditas' grown in a soilless substrate was examined. In vitro-grown acclimatized plantlets were transplanted into the pots containing a coir-based substrate. A nutrient solution containing 0, 50, or $100mg{\cdot}L^{-1}$ Si was supplied through a drip-irrigation system. After 5 months of cultiv ation, S i-treated and -untreated p lants were grown at 10, 25, or $40{\pm}1^{\circ}C$ under a 12 h photoperiod with $530{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD and 60% RH. After 7 days, chlorophyll content and chlorophyll fluorescence parameters were measured. Silicon nutrition had a negative effect on growth characteristics of N. exaltata 'Corditas'. However, Si-treated plants had more tolerance to temperature stress than the control plants. The Fv/Fm value was not significantly different when the plants were exposed to $25^{\circ}C$. However, significant difference in Fv/Fm was recorded when plants were exposed to 10 or $40^{\circ}C$. Thus, Fv/Fm could be used as an indicator of low and high temperature tolerance in ferns. The present study also suggests that application of Si may be used to enhance temperature tolerance of ferns.

Screening for Antioxidative Activities of Extracts from Aerial and Underground Parts of Some Edible and Medicinal Ferns (식용 및 악용 양치식물에서 부위별 추출물의 항산화활성 탐색)

  • Jeong, Jin-A;Kwon, Su-Hyun;Lee, Cheol-Hee
    • Korean Journal of Plant Resources
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    • v.20 no.2
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    • pp.185-192
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    • 2007
  • The different parts of 8 edible and medicinal ferns were extracted with 80% ethanol and the bioactive substances and antioxidant activities were investigated. Total polyphenol content was highest in Cyrtomium fortunei rhizome ($57.32mg{\cdot}g^{-1}$) and followed by C. fortunei root, Pyrrosia lingua aerial part and Onoclea sensibilis var. interrupta aerial part. Total flavonoid contents ranged from 1.95 (Onoclea sensibilis var. interrupta rhizome) to $27.51mg{\cdot}g^{-1}$ (O. sensibilis var. interrupta aerial part). Among the samples tested, C. fortunei root and rhizome were found to be most effective in both DPPH and ABTS radical scavenging assay. Except in Selaginella tamariscina underground part and Osmunda japonica aerial part, most of the tested samples showed strong potential (above 87%) in inhibition rate on linoleic acid oxidation.