• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.1
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• pp.32-40
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• 2022

The trade-off between morphology and physical function may vary according to ecological traits. Taking a quantitative approach, we attempted to analyze the differences in the skeletal shape of the lower body and limbs in relation to the ecological traits of four anuran species (Dryophytes japonicus, Glandirana rugosa, Pelophylax nigromaculatus, and Lithobates catesbeianus) occurring in South Korea. Body size, locomotor mode, microhabitat, trophic positions, and predator defense mechanisms were selected for the ecological traits of the anurans. The pelvis, ilium, and urostyle, which are associated with locomotor performance, were selected for the skeletal shape of the lower body. The ratio of limbs, which is related to locomotor mode and microhabitat, was confirmed by analyzing the skeletons of the forelimbs (radio-ulnar and humerus) and hindlimbs (femur and tibiofibular). Both landmark-based geometric morphometrics and traditional methods were used for skeletal shape comparison. The skeletal shape of the lower body was completely different among the four species, whereas the ratio of the limbs was only different in D. japonicus. The skeletal shape of the lower body may be related to body mass and predator defense mechanisms, whereas the ratio of the limbs was related to the locomotor mode and microhabitat. Quantifying these morphological differences among various species can help elucidate the mechanisms of behavioral and morphological changes in response to ecological effects.

• Journal of Species Research
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• v.9 no.2
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• pp.147-161
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• 2020

Seven new species of two genera Scalarispongia and Smenospongia (Demospongiae: Dictyoceratida: Thorectidae) are described from Gageo Island and Jeju Island, Korea. Five new species of Scalarispongia are compared to nine reported species of the genus by the skeletal structure. Scalarispongia viridis n. sp. has regular ladder-like skeletal pattern arranged throughout the sponge body and has pseudo-tertiary fibres. Scalarispongia favus n. sp. is characterized by the honeycomb shape of the surface and is similar to Sc. flava in skeletal structure, but differs in sponge shape. Scalarispongia lenis n. sp. is similar to Sc. regularis in skeletal structure but has fibers that are smaller in size. Scalarispongia canus n. sp. has irregular skeletal structure in three dimensions and ladder-like which comes out of the surface and choanosome. Scalarispongia subjiensis n. sp. has pseudo-tertiary fibres and its regular ladder-like skeletal pattern occurs at the choanosome. Two new species of Smenospongia are distinguished from the other 19 reported species of the genus by the skeletal structure. Smenospongia aspera n. sp. is similar to Sm. coreana in sponge shape but new species has rarely secondary web and thin and thick bridged fibres at near surface. Smenospongia mureungensis n. sp. has very simple skeletal structure.

• Molecules and Cells
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• v.24 no.2
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• pp.177-184
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• 2007

Approximately 200 individual skeletal elements, which differ in shape and size, are the building blocks of the vertebrate skeleton. Various features of the individual skeletal elements, such as their location, shape, growth and differentiation rate, are being determined during embryonic development. A few skeletal elements, such as the lateral halves of the clavicle and parts of the skull are formed by a process called intramembranous ossification, whereby mesenchymal cells differentiate directly into osteoblasts, while the majority of skeletal elements are formed via endochondral ossification. The latter process starts with the formation of a cartilaginous template, which eventually is being replaced by bone. This requires co-regulation of differentiation of the cell-types specific for cartilage and bone, chondrocytes and osteoblasts, respectively. In recent years it has been demonstrated that Wnt family members and their respective intracellular pathways, such as non-canonical and the canonical $Wnt/{\beta}$-catenin pathway, play important and diverse roles during different steps of vertebrate skeletal development. Based on the recent discoveries modulation of the canonical Wnt-signaling pathway could be an interesting approach to direct stem cells into certain skeletal lineages.

• Journal of Species Research
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• v.12 no.1
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• pp.38-47
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• 2023

Seven new species of genus Dysidea (Demospongiae: Dictyoceratida: Dysideidae) are described from Jejudo Island and Geomundo Island, Korea. These new species are compared with other reported species in fibre structure and arrangement, and cored detritus. Dysidea reticulum n. sp. is similar to D. glavea in skeletal structure but differ in sponge shape. Dysidea simplex n. sp. is close to D. glavea with loosely arranged skeletal structure but fibres in this new species are not cored with large sands. Dysidea pyeongdaensis n. sp. is characterized by tube-like surface oscules open toward the sandy bottom. Dysidea capillus n. sp. is similar to D. dokdoensis in skeletal structure, but differs in long surface conules. Dysidea mukriensis n. sp. is close to D. corallina in distinct dense surface conules, but differs in sponge shape and skeletal structure. Dysidea membrana n. sp. is similar to D. sabulum in primary fibres cored with numerous large sands, but differs in sponge surface conules and secondary fibres. Dysidea chujaensis n. sp. is unique in the sponge shape and skeletal structure.

• The korean journal of orthodontics
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• v.49 no.3
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• pp.170-180
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• 2019

Objective: The purpose of this study was to investigate the relationship between the facial skeletal patterns and the shape of the mandibular symphysis in adults with malocclusion by using a structural equation model (SEM). Methods: Ninety adults who had malocclusion and had records of facial skeletal measurements performed using cone-beam computed tomography were selected for this study. The skeletal measurements were classified into three groups (vertical, anteroposterior, and transverse). Cross-sectional images of the mandibular symphysis were analyzed using generalized Procrustes and principal component (PC) analyses. A SEM was constructed after the factors were extracted via factor analysis. Results: Two factors were extracted from the transverse, vertical, and anteroposterior skeletal measurements. Latent variables were extracted for each factor. PC1, PC2, and PC3 were selected to analyze the variations of the mandibular symphyseal shape. The SEM was constructed using the skeletal variables, PCs, and latent variables. The SEM showed that the vertical latent variable exerted the most influence on the mandibular symphyseal shape. Conclusions: The relationship between the skeletal pattern and the mandibular symphysis was analyzed using a SEM, which showed that the vertical facial skeletal pattern had the highest effect on the shape of the mandibular symphysis.

• Imaging Science in Dentistry
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• v.48 no.3
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• pp.185-190
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• 2018

Purpose: The aim of this study was to compare the location and the shape of the mandibular lingula in skeletal class I and III patients using panoramic radiography and cone-beam computed tomography. Materials and Methods: The sample group included 190 skeletal class I patients and 157 class III patients. The location of the lingula in relation to the deepest point of the coronoid notch was classified into 3 types using panoramic radiographs. The shapes of the lingulae were classified into nodular, triangular, truncated, or assimilated types using cone-beam computed tomographic images. The data were analyzed using the chi-square test. Results: The tips of the lingulae were at the same level as the coronoid notch in 75.3% of skeletal class I patients and above the coronoid notch in 66.6% of class III patients. The positions of the lingulae in relation to the deepest point of the coronoid notch showed statistically significant differences between class I and class III patients. The most common shape was nodular, and the least common was the assimilated shape. Although this trend was not statistically significant, the triangular shape was more frequently observed in class III patients than in class I patients. Conclusion: The locations and the shapes of the mandibular lingulae were variable. Most of the lingulae were at the same level as the coronoid notch in skeletal class I patients and above the coronoid notch in skeletal class III patients. The nodular and assimilated-shaped lingulae were the most and the least prevalent, respectively.

• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.277-284
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• 2020

Four new species of genus Scalarispongia (Demospongiae: Dictyoceratida: Thorectidae) are described from Jejudo Island, Korea. These new species of Scalarispongia are compared with 14 reported species of the genus by the skeletal structure. Scalarispongia songakensis n. sp. is similar to S. lenis in sponge shape but differs in skeletal structure and meshes are not divided into two sections. The length of secondary fibres between primary fibres of this new species is much longer than S. lenis'. Scalarispongia radicula n. sp. is resembles S. songakensis in sponge shape, but this new species has pseudo-tertiary fibres at the sponge base. Scalarispongia maraensis n. sp. is very similar to S. subjiensis in sponge shape but primary fibres of this new species are not simple because fibres have wide webbing. Scalarispongia massa n. sp. is characterized by the large mass sponge shape and numerous open oscules form a long ling on the ridge of the sponge.

• Journal of Species Research
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• v.13 no.1
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• pp.32-40
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• 2024

Five new species of the genus Hyattella (Dictyoceratida: Spongiidae) were collected from Jejudo and Gageodo, Korea: Hy. gukheulensis n. sp., Hy. regularis n. sp., Hy. lenis n. sp., Hy. membrana n. sp., and Hy. asper n. sp. Hyattella gukheulensis n. sp. is similar to Hy. munseomensis Sim et al., 2015 in shape, but differs in skeletal structure. Hyattella regularis n. sp. is close to Hy. bakusi Sim et al., 2015 but differs in regular secondary fibres at the surface membrane. Hyattella lenis n. sp. is unique by having numerous windings at the surface. Hyattella membrana n. sp. is similar to Hy. bakusi Sim et al., 2015 in shape, but differs in surface and skeletal fibres. Hyattella asper n. sp. is close to Hy. lendenfeldi Sim and Lee, 2014 in skeletal fibres, but differs in thin secondary fibres. This new species has numerous dense cored primary fibres.

• Animal cells and systems
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• v.8 no.3
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• pp.139-143
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• 2004

Two new species of the genus Psammocinia (Dictyoceratida, Irciniidae), P. conulosa n. sp. and P. ulleungensis n. sp., are described from Namhaedo Island and Ulleungdo Island, Korea. Psammocinia conulosa n. sp. seems to be close to both P. amodes Cook and Bergquist, 1998 and P. hawere Cook and Bergquist, 1996 on the basis of the skeletal structure. However, these three species are clearly separated by the following differences: Shape of P. amodes is spatulate and thin, with a broad blade narrowing to a semi-cylindrical stalk; P. hawere forms cups with a shallow excavated bowl, and attached to the substratum by a narrow base. The whole surface of the new species is very finely conulose. Psammocinia ulleungensis n. sp. is similar to P. gageoensis Sim and Lee, 2001 in shape, but this species is easily distinguished from P. gageoensis by the simple skeletal structure.

• Journal of Species Research
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• v.6 no.2
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• pp.190-194
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• 2017

Two new species of the genus Luffariella (Dictyoceratida: Thorectidae), L. tubula n. sp. and L. koreana n. sp. were collected from Jeju-do, Korea. These species differ significantly from the previously reported five species in terms of shape and skeletal structure. L. tubula n. sp. has two categories in thickness of secondary fibres which were different from other species. L. koreana n. sp. is very similar to L. variabilis from Tahiti in skeletal structure, but differs in sponge shape with irregular branching and indistinct surface conules. Primary fibres of the two new species are separated from secondary and tertiary fibres.