• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.04a
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• pp.49-55
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• 2003

The morphology of the leaves and the flowers of angiosperms exhibit remarkable diversity. One of the factors showing the greatest variability of leaf organs is the leaf index, namely, the ratio of leaf length to leaf width. In some cases, different varieties of a single species or closely related species can be distinguished by differences in leaf index. To some extent, the leaf index reflects the morphological adaptation of leaves to a particular environment. In addition, the growth of leaf organs is dependent on the extent of the expansion of leaf cells and on cell proliferation in the cellular level. The rates of the division and enlargement of leaf cells at each stage contribute to the final shape of the leaf, and play important roles throughout leaf development. Thus, the control of leaf shape is related to the control of the shape of cells and the size of cells within the leaf. The shape of flower also reflects the shape of leaf, since floral organs are thought to be a derivative of leaf organs. No good tools have been available for studies of the mechanisms that underlie such biodiversity. However, we have recently obtained some information about molecular mechanisms of leaf morphogenesis as a result of studies of leaves of the model plant, Arabidopsis thaliana. For example, the ANGUSTIFOLIA (AN) gene, a homolog of animal CtBP genes, controls leaf width. AN appears to regulate the polar elongation of leaf cells via control of the arrangement of cortical microtubules. By contrast, the ROTUNDIFOLIA3 (ROT3) gene controls leaf length via the biosynthesis of steroid(s). We provide here an overview of the biodiversity exhibited by the leaf index of angiosperms. Taken together, we can discuss on the possibility of the control of the shapes and size of plant organs by transgenic approaches with the results from basic researches. For example, transgenic plants that overexpressed a wild-type ROT3 gene had longer leaves than parent plants, without any changes in leaf width. Thus, The genes for leaf growth and development, such as ROT3 gene, should be useful tools for the biodesign of plant organs.

• Journal of Plant Biology
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• v.30 no.2
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• pp.151-170
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• 1987

Taxa of genus Callicarpa in Korea were described taxonomically and studied interspecific relationships, based on the leaf length, leaf width, peduncle length, fruit width and geograhic distribution. Among 12 taxa reported previously in Korea, 3 forms of C. japonica were unifed to original species, C. japonica var. glabra was reserved, Whereas C. shirasawana was not distributed in Korea. As a result, 7 taxa belonging to 3 species, 4 varieties of genus Callicarpa remained. C. japonica complex is considered to be more advanced among the species compared with the bract shapes.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.316-318
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• 2003

An eigen-analysis of the coherency matrix provides the polarimetric scattering mechanisms with the matrix characterizing parameters. In this paper, the coherency matrices of deciduous and coniferous vegetation are calculated using the analytical method. The Generalized Rayleigh-Gans approximation is used to model backscattering from distributed coniferous and deciduous leaves. The characteristics of eigen-parameters of simulated coherency matrix for deciduous and coniferous leaves with respect to the leaf shapes and orientations are illustrated.

• Journal of the Korea Computer Graphics Society
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• v.21 no.5
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• pp.1-10
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• 2015

This study proposes a method of developing authoring tool that can easily and intuitively generate diverse digital leaves that compose virtual landscape. The main system of the proposed authoring tool consists of deformation method for the contour of leaf blade based on image warping, procedural modeling of leaf vein and visualization method based on mathematical model that expresses the color and brightness of leaves. First, the proposed authoring tool receives leaf input image and searches for contour information on the leaf blades. It then designs leaf blade deformation method that can generate diverse shapes of leaf blades in an intuitive structure using feature-based image warping. Based on the computed leaf blade contour, the system implements the generalized procedural modeling method suitable for the authoring tool that generates natural vein patterns appropriate for the leaf blade shape. Finally, the system applies visualization function that can express color and brightness of leaves and their changes over time using a mathematical model based on convolution sums of divisor functions. This paper provides texture support function so that the digital leaves that were generated using the proposed authoring tool can be used in a variety of three-dimensional digital contents field.

• KSBB Journal
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• v.27 no.3
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• pp.157-160
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• 2012

When iron oxide magnetic nanoparticles were synthesized by co-precipitation method using aqueous ammonia as reducing agent, the synthesized particles were aggregated and thus precipitation occurred. Using Magnolia kobus leaf extract as reducing agent, spherical nanoparticles of 50~200 nm were synthesized with low yield. By using both Magnolia kobus leaf extract and aqueous ammonia as reducing and stabilizing agents, smaller nanoparticles of 40~120 nm could be synthesized with various shapes. The synthesized magnetic nanoparticles were characterized with field emission transmission electron microscopy (FE-TEM) and scanning electron microscopy (SEM). TEM and SEM images showed that the magnetic nanoparticles are a mixture of triangles, tetragons, rods and spherical structures.

• Imaging Science in Dentistry
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• v.49 no.2
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• pp.153-158
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• 2019

Purpose: The purpose of this study was to investigate variations in velar shape according to age, sex, and race using magnetic resonance imaging (MRI). Materials and Methods: The study sample consisted of 170 participants (85 children, 85 adults) between 4 and 34 years of age. Velar morphology was visually classified using midsagittal MRI scans for each participant by 2 independent raters. Inter- and intra-rater reliability was assessed. Statistical analyses were performed to identify correlations of velar shape with sex, age, and race. Results: The most frequent velar shape was "butt" for both adults(41%) and children (58%) in this study. The least common shapes for adults were "leaf" and "S." The children did not exhibit any "leaf" or "straight" velar shapes. A statistically significant difference was noted for age with respect to velar shape (P=0.014). Sex and race were found to have no significant impact on velar shape in this study. Conclusion: When using MRI to evaluate velar morphology, the "butt" shape was most common in both children and adults. Velar shape varied significantly with age, while race and sex did not have a significant impact.

• Asian Journal of Atmospheric Environment
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• v.7 no.1
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• pp.1-7
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• 2013

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

• Korean Journal of Plant Resources
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• v.9 no.2
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• pp.165-170
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• 1996

The study was carried out to identify the characteristics of leafy shapes, and to establish the cultural practices such as shading condition, fertilization method, and planting distance of Cirsium nipponicum. Leaf shapes in this plant consist of two kinds, lobation and non-lobation which has two spur type showing large and small spur. Protein band patterns showed that a new protein band in non-lobation with large spur was appeared at the 116.4kDa. For shading condition and fertilization method, number of stems in non-shading and organic matter treatment was higher than that of shading 55% with 3.7. Fresh leaf yield on non-shading and organic matter treatment was higher than that of other treatments. Growth characteristics of leaf number was increased in the $60\times30cm$ treatment, but was redeuced to some extent compared with $60\times45cm$. To increase the fresh leaf yield, the optimum planting distance was $30\times20cm$ with 4,100kg/10a.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.332-336
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• 1981

Seven soybean varieties and 21 F 2 hybrids of a diallel cross among these varieties were used as the materials, and genetic studies were conducted to evaluate the frequency and distribution of genes governing the characters of soybean leaf shapes. Partial dominance was exhibited by petiole length of trifoliates, petiole length of terminal leaflets, length of terminal leaflets, length of lateral leaflets, width of terminal leaflets Mean values of length of terminal leaflet were higher than those of lateral leaflets and length of leaflets were higher than width of leaflets, but mean values of width of terminal leaflets were shorter than those of lateral leaflets.

• Applied Microscopy
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• v.43 no.1
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• pp.34-39
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• 2013

Glandular and nonglandular trichomes on the leaf surface of Plectranthus tomentosa were investigated by variable pressure field emission scanning electron microscopy (VP-FESEM). The segments of the plant's leaves were directly mounted without any specimen preparation, and examined at ambient temperature using a variable pressure secondary electron (SE) detector under ca. 15 Pa. Foliar trichomes maintained their shapes and structures without severe surface collapse or charging. The adaxial leaf surface was abundantly covered with different types of trichome. Nonglandular trichomes consisted of a basal cell and a long (up to ca. $300{\mu}m$) stalk. Meanwhile, capitate glandular trichomes had a secretory head and a short or long stalk. Peltate glandular trichomes with globose secretory heads were observed in close contact with the leaf epidermis. Spherical projections on the secretory head showed the secretion process of glandular trichomes. In addition to the trichomes, oval stomata were distributed on the abaxial leaf surface. These results suggest that ambient VP-FESEM can be used to classify the dehydration-sensitive foliar trichomes of succulent plants by SE imaging. At the FESEM resolution, this approach facilitates the rapid and detailed morphological analysis of a variety of trichomes in diverse plant taxa with reduced labor and preparation.