• Title/Summary/Keyword: 기근

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Morphological and Cellular Characteristics of Aerial Roots in the Epiphytic American Ivy (Parthenocissus sp.) (착생식물 기근의 형태 및 세포학적 특성)

  • Yim, Ji-Eun;Kim, In-Sun
    • Applied Microscopy
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    • v.32 no.4
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    • pp.329-337
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    • 2002

  • The morphology and cellular characteristics of adventitious roots, viz aerial roots, in the epiphytic American Ivy were examined to reveal structural changes of the aerial root upon surface attachment. Immature aerial roots were composed of parenchyma cells with dense cytoplasm containing plastids, however, the upper and lower epidermis were not distinguished. At early development, electron-dense substances (EDS) were constituents of much of the aerial root tissue, but the distribution of EDS varied within the tissue. The deposits appeared most concentrated in the superficial cell layers, with lesser amounts in cell layers closer to the cortex. Electron micrographs revealed that EDS deposits were always found in the vacuole, and were mainly associated with the tonoplast. While most of them occurred in the vacuole as small spherical deposits adjacent to the tonoplast, some deposits were oddly shaped or larger in size. Many of the vacuoles eventually filled with EDS, but the EDS content in those vacuoles decreased substantially after initial attachment to the surface. When the vacuoles became almost empty, cells near the epidermis already exhibited irregularity in outline. Subsequent breakdown of cellular components took place in the cells while they were still attached to the surface. This study suggests the potential role of EDS as substances involved in the surface attachment of the plant, however, further studies must be conducted to reveal the nature of EDS and the effects of EDS storage within these vacuoles.

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The Marrakesh Treaty and the Tasks of Library Services for Persons with Disabilities (마라케시 조약과 도서관 장애인서비스 과제)

  • 윤희윤
    • Journal of the Korean Society for Library and Information Science
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    • v.56 no.3
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    • pp.73-91
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    • 2022

  • For everyone, books are not only a passage to break down temporal and spatial barriers, but also a passport to the world. However, books are neither a passage nor a passport for persons with print disabilities. They are suffering from a severe book famine, with only 1-7% of alternative materials in accessible formats. The Marrakesh Treaty is an international agreement promoted by the WBU and WIPO to reduce such access gaps and inequalities. Accordingly, this study intensively analyzed and linked the global book famine and the Marrakesh Treaty for the persons with print disabilities including the blind and visually impaired, and suggested strategic tasks and implementation plans to strengthen the services of the disabled in domestic libraries. The government and libraries should concentrate all their competencies on improving awareness, inducing standardization of alternative materials in the publishing industry, amending and supplementing the copyright act and related laws, strengthening the digital file collection and service of the National Library for the disabled, and developing and applying library guidelines to implement the Marrakesh Treaty. This is because if food supports the body of the disabled, reading fosters their spirit. In order to solve the global book famine for persons with print disabilities, it is necessary to improve the publishing industry's cartels, copyright holders' barricades, and the weak platform of the library industry. All copyright holders, publishers, and libraries should participate in reducing the 95% gap in access between non-disabled and disabled people. That is the mantra of the book famine.

  • https://doi.org/10.4275/KSLIS.2022.56.3.073 인용 PDF KSCI