• 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.

• Progress in Medical Physics
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• v.5 no.2
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• pp.49-55
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• 1994

Multileaf Collimator is an essential tool for conformal therapy. We have measured the scallop penumbars of a poligon-shape field produced by Multileaf Collimator(MLC) with various leaf widths and the penumbra from conventional block, and compared the difference between them for the energy of photons, leaf widths, and angle of filed edges in order to find out the optimum leaf width. In addition, we have simulated a treatment of 20 factionations with errors of patient positioning. Optimum cost-benefit balanced leaf width is 8 mm.

• Korean Journal of Plant Taxonomy
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• v.49 no.1
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• pp.1-7
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• 2019

Early leaves within the Viola albida complex were investigated by scanning electron microscopy in order to determine the morphological segments during morphogenesis. The early leaf development of V. albida var. albida could be morphologically divided into the eight stages in the following order: I, the initiation of shoot germination; II, the conical growth directionally of the leaf; III, the adaxial and abaxial formation of the leaf; IV, the initiation of the stipule; V, the formation of a transitional zone between the leaf blade and petiole; VI, the expansion of the upper part of the leaf blade; VII, the formation of almost all parts of the early leaf; VIII, the early simple leaf. Viola albida var. takahashii differs from V. albida var. albida by additional stages, i.e., V-1, the initiation of the first lateral lobe at the both lateral parts of the leaf after the stage V and an early lobed leaf. Viola albida var. chaerophylloides is also distinguished from two taxa by two developmental features, V-2, the initiation of a second lateral lobe below of the first lateral lobe, and an early palmately compound leaf. These findings suggest that the Viola albida complex would be in the process of peramorphosis, showing developmental changes in a chain of events, leading to a different leaf shape. These data would also be useful for isolating genes that give rise to different leaf morphogenesis outcomes among the taxa in the Viola albida complex.

• Journal of Digital Contents Society
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• v.16 no.2
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• pp.235-244
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• 2015

This study proposes a leaf modeling method that uses feature-based warping for efficient generation of various digital leaves. The proposed method uses warping method, one of image processing application techniques that can control various shapes of leaves in an easy, intuitive way, and generate natural patterns of veins efficiently. First, information on approximated contour is detected from a leaf blade image to identify the shape of a blade. Based on this, control line is automatically calculated to be used for feature-based warping. Then, control line-based warping is conducted to modify forms of leaf blade images in an intuitive way, automatically generating leaves of various shapes. And natural vein patterns are generated by applying a contour-based venation growth algorithm from contour information of the modified leaf blade images. This study performs experiments to verify whether various shape of leaves that comprise plants can be efficiently generated using a sample binary image of a blade. Also, we demonstrate that express the natural growth of leaves by applying warping to the growth of the leaf blade.

• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.407-412
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• 1990

Morphological characters on the leaf nectar gland of Korean Prunus 4 species and 1 form were observed by SM. The results were summarized as follows ; The shapes of nectar gland on the plane figure were two, the circular and the irregular ovate. The species of circular shape were P. maackii, P. maximowiczii, P. sargentii and P. yedoensis. The irregular ovate shape was only one species, P. pendula for. ascendens. The shapes of nectar gland on the side figure were the reentrant apices and the rounded. The reentrant apices were two shapes. First, the species of the center reentrant was three, P. maackii, P. sargentii and P. yedoensis. Second, the species of the irregular reentrant was P. pendula for. ascendens. The rounded apex was only one species, P. maximowiczii. Especially on the P. pendula for. ascendens, the upheaval situation on surface of leaf blade was due to the sinking of reverse part of leaf blade at the nectar gland. The point of this abnormal shape was well distinguished from the other species. On the frequency by the part of leaf with nectar gland, the species to be observed only at the leaf base was P. pendula for. ascendens, the other species was observed two part of leaf base and petioles. In this study, some Prunus species were well keyed out on the basis of the morphological characters of leaf nectar gland.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.576-583
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• 2009

Based on the stem analysis and biomass measurement of 36 trees and 1,576 branches in Pinus sylvestris var. mongolica (Mongolian pine) plantations of Northeast China, this study was conducted to develop estimation model equation for leaf biomass of a single tree and branch, to examine the vertical distribution of leaf biomass in the crown, and to evaluate the proportional ratios of biomass by tree parts, stem, branch, and leaf. The results indicated that DBH and crown length were quite appropriate to estimate leaf biomass. The biomass of single branch was highly correlated with branch collar diameter and relative height of branch in the crown, but not much with stand density, site quality, and tree height. Weibull distribution function would have been appropriate to express vertical distribution of leaf biomass. The shape parameters from 29 sample trees out of 36 were less than 3.6, indicating that vertical distribution of leaf biomass in the crown was displayed by bell-shaped curve, a little inclined toward positive side. Apparent correlationship was obtained between leaf biomass and branch biomass having resulted in linear function equation. The stem biomass occupied around 80% and branch and leaf made up about 20% of total biomass in a single tree. As the level of tree class was increased from class I to class V, the proportion of the stem biomass to total biomass was gradually increased, but that of branch and leaf became decreased.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.23-28
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• 1999

To examine taxonomic relationships among 53 plums derived from Prunus cerasifera, P. domestica, and P. salicina, principal component analysis (PCA) and cluster analysis on 27 morphological characters were conducted. Of 27 characters, leaf size, leaf shape, and leaf hair were useful characters for plum identification and understanding of taxonomic relationships among them. Leaf length, petiole length, number of leaf nectaries, leaf shape, leaf base, and date of full blooming showed the clear differences between P. salicina group and P. domestica group. Results of cluster analysis using scores of the first three principal components indicated that 53 plums could be grouped into P. salicina-P. cerasifera, P. domestica, and P. spinosa phenon at 1.0 of average distance in UPGMA. Although PCA was useful for rough classification of plums, much more characters were needed for the exact classification.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.2
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• pp.99-109
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• 1985

The present studies were carried out to obtain some basic informations of the breeding of tobacco varieties. Genetically divergent 8 varieties, 3 flue-cured, 2 burley and 3 sun-cured tobaccos, were used in half diallel cross. In order to analyze the heterosis, combining abilities, modes of inheritance and correlations for some agronomic and chemical characters, 8 parents and 28 $F_1$ were tested. The results obtained were summarized as follows: The percentages of heterosis for stem diameter, internode length and total sugar content in $F_1$ hybrid were 3.6%, 3.1% and 10.6%, whereas these for days to flower, total alkaloids and leaves per plant were -6.3%, -6.9% and -5.0%, respectively. Yield had significant positive genotypic correlations with plant height, days to flower and leaf length, but negative with internode length and total sugar content. It also had significant prositive phenotypic correlations with plant height, days to flower, leaves per plant, leaf length, leaf width and leaf shape index (Leaf length/leaf width). General (GCA) and specific combining abilities (SCA) for all characters of $F_1$ hybrid were significant. The effects of GCA were positive on yield, plant height, stem diameter, leaves per plant and days to flower of Burley 21. And those were positive on yield, leaf shape index and plant height, but negative on leaves per plant and total nitrogen of Hicks. The effects of SCA for yield and leaves per plant were greater than those of others on the combinations of Coker 139 and Burley type, respectively.

• Korean Journal of Plant Taxonomy
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• v.37 no.3
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• pp.275-308
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• 2007

For 20 taxa of Korean Allium, including 16 species and 5 varieties, examined were morphological characters (i.e. sexuality, structure and shape of underground part, types and growing patterns of leaf and scape, and shapes of perianth, filament and pistil). The specialization and the evolutionary trends of taxonomic characters were inferred from morphological examination. Taxonomic relationships and system of Korean Allium were also studied. The characters showing evolutionary trends were the structure and shape of underground part including rhizome and bulb, leaf, scape, inflorescens, filament and ovary. It seemed that thin and short rhizome developed from thick and long one, and the membranous simple bulb tunic evolved into fibrous reticulate one. The presence of hyaline sheath in A. monanthum of sect. Microscordum was apomorphic. Both angular leaf blade with 2-rowed vascular bundle and flat blade with 1-rowed vascular bundle were developed from terete one with 2-rowed vascular bundle. The base of filament have differentiated from entire to toothed, and 2-ovuled ovary as well as erect scape before flowering was plesiomorphic type. In addition, sexuality, structure of underground part, the presence of hyaline sheath and cross-section structure of leaf were taxonomic characters with the level of the subgenus in this genus. Shape of rhizome, bulb, leaf, scape and pedicel discriminated each section from other ones in the subgenera easily. The shape and arrangement of perianth and filaments were the diagnostic characters for species level along with shape of ovary and stigma.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.285-292
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• 2011

In plants, heteroblasty reflects the morphological adaptation during leaf development according to the external environmental condition and affects the final shape and size of organ. Among parameters displaying heteroblasty, leaf index is an important and typical one to represent the shape and size of simple leaves. Leaf index factor is eventually determined by cell proliferation and cell expansion in leaf blades. Although several regulators and their mechanisms controlling the cell division and cell expansion in leaf development have been studied, it does not fully provide a blueprint of organ formation and morphogenesis during environmental changes. To investigate genes and their mechanisms controlling leaf index during leaf development, we carried out molecular-genetic and physiological experiments using an Arabidopsis mutant. In this study, we identified macrophylla (mac) which had enlarged leaves. In detail, the mac mutant showed alteration in leaf index and cell expansion in direction of width and length, resulting in not only modification of leaf shape but also disruption of heteroblasty. Molecular-genetic studies indicated that mac mutant had point mutation in ROTUDIFOLIA3 (ROT3) gene involved in brassinosteroid biosynthesis and was an allele of rot3-1 mutant. We named it mac/rot3-5 mutant. The expression of ROT3 gene was controlled by negative feedback inhibition by the treatment of brassinosteroid hormone, suggesting that ROT3 gene was involved in brassinosteroid biosynthesis. In dark condition, in addition, the expression of ROT3 gene was up-regulated and mac/rot3-5 mutant showed lower response, compare to wild type in petiole elongation. This study suggests that ROT3 gene has an important role in control of leaf index during leaf expansion process for proper environmental adaptation, such as shade avoidance syndrome, via the control of brassinosteroid biosynthesis.