• Animal cells and systems
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• v.13 no.3
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• pp.323-329
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• 2009

We analyzed partial sequences of cytochrome b (cyt-b), a mitochondrial DNA (mtDNA) gene, to determine the genetic relationships between six horsehead fish species: Branchiostegus japonicus, Branchiostegus albus, Branchiostegus auratus, Branchiostegus argentatus, Branchiostegus wardi, and an unidentified Branchiostegus species. The specimens were collected in Korea, China, Japan, and Vietnam. We compared their molecular phylogenetic relationships inferred from mtDNA cyt-b sequences with an osteological analysis. The unidentified species, B. sp., was similar to B. albus in terms of the lack of triangular silver-white dot at the posterior region of eyes (vs. large one present in B. japonicus), but was also similar to B. japonicus in terms of the presence of a straight-shaped first hemal spine (vs. a curve-shaped hemal spine in B. albus). Analysis of the mtDNA cyt-b sequences indicated that the smallest estimated sequence divergence was between the B. japonicus and B. sp. (0.70-0.94%), whereas the largest difference was between B. auratus and B. argentatus (23.06-23.36%). Both the maximum parsimony and maximum likelihood trees showed that the B. sp. was closely clustered with B. japonicus, and that B. auratus was most distant from the other species. When comparing the osteological characters, UPGMA tree showed that the B. japonicus and B. sp. were the most closely clustered species, and B. auratus was the most distantly clustered fish relative to the other species. The shape of the nasal, otolith and first hemal spine was informative for distinguishing B. auratus from the other species. These osteological differences were consistent with the differences in mtDNA.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.294-304
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• 2016

Members of the genus Brassica, which are known as oil crops or cruciferous vegetables, are widely cultivated in Canada, Australia, Asian and Europe. Because Brassica species have high yields, are well adapted to their environments, and are self-incompatible, the germplasm is abundant. Previous studies have reported abundant genetic diversity even within Brassica subspecies. In Korea, fresh cabbage leaves are eaten with roast meat, and to meet the current popular demand, new varieties are being increasingly bred. To determine the genetic diversity and relationships among the cabbage vegetables in Korea, we evaluated the genetic variation of 18 accessions based on 5S and 18S ribosomal RNA (rRNA) gene sequences. We detected many variable nucleotide sites, especially in the 5S rRNA gene sequences. Because the length of the 18S rRNA gene might influence the dissimilarity rate statistics, we used both the 5S and 18S sequences to analyze the phylogenetic relationships. S7 (B. oleracea) showed the most distant phylogenetic relationship with the other Brassica species. Interestingly, B2 (B. oleracea), B15, and B18 (B. campestris) have three different types of leaf profiles, and were divided into one group, and the other Brassica species formed another group. Statistical analysis of interspecies and intraspecies genetic distances revealed that B. campestris L. showed higher genetic diversity than B. oleracea L. This work provides additional data that facilitates the evaluation of the genetic variation and relationships among Brassica species. The results could be used in functional plant breeding programs to improve Brassica crops.

• Korean Journal of Computational Design and Engineering
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• v.4 no.2
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• pp.121-126
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• 1999

Existing data structures for non-manifold solid modelers use basic dat entities, such as vertex, edge, loop, face, shell, and region to find adjacency relationships. But, no one clearly identified what additional types of data entitles are necessary to represent incidence relationships. In this paper, we classified the boundary information of vertex, edge, face , and region from the 3-D space view. As the results we can clearly define the boundary information required for adjacency relationships. The existing B-rep data structures for solid modeler are compared whether they have the required boundary information.

• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.342-346
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• 2006

Anatomical characters of the Bupleurum latissimum Nakai, an endemic species of Korea, were investigated to confirm its phylogenetic relationships. Compare to other species with anatomical characters, B. latissimum is very similar with B, euphorbioides and B, longeradiatum in point of lacking of pith in the stem, shape of involucres, number of vascular bundles in radical leaf and cauline leaf, and lacking stomata in adaxial leaf surface. The other hand, protruded pollen aperture character appears in B. latissimum and B. euphorbioides. On the based of anatomical characters, therefore, B. latissimum has closest relationships with B. euphorbioides and B. longeradiatum. It also needs molecular study including Asian species in order to confirm phylogenetic position and speciation process apparently.

• Animal cells and systems
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• v.4 no.2
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• pp.117-121
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• 2000

Genetic relationships among six species of the genus Rana from Korea were investigated by complete nucleotide sequence analyses of mitochondrial cytochrome b gene (1143 bp). Based on Kimura-2-parameter distance, the interspecific sequence differences of cytochrome b gene within the genus Rana were ranged from 7.83% to 25.00%. The genetic distances were 7.83% between R. nigromaculata and R. plancyi, 8.47% between two types of R. rugosa (type A and B), 10.42% between the brown frogs (R. amurensis and R. dybowskii), 16.11% between R. dybowskii types 1 and 2 and 12.36% between pond frogs (R. nigromaculata and R. plancyi) and R. catesbeiana. In the neighbor-joining and parsimony trees, R. catesbeiana was more closely related to pond frogs than brown frogs. R. dybowskii types 1 and 2 were considered to be at a distinct and specific level of differentiation (16.11%), while two types of R. rugosa were suspected to be at a subspecific level (8.47%).

• Communications of the Korean Mathematical Society
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• v.31 no.2
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• pp.277-294
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• 2016

The aim of this paper is to present the classical sets of sequences and related matrix transformations with respect to the b-metric. Also, we introduce the relationships between these sets and their classical forms with corresponding properties including convergence and completeness. Further we determine the duals of the new spaces and characterize matrix transformations on them into the sets of b-bounded, b-convergent and b-null sequences.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.790-793
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• 2020

Length-weight relationships (LWR) for 27 fish species inhabit Southern sea in Korea were investigated to describe several biological characters. Total 7,399 individuals were collected by R/V Tamgu-20 using bottom trawl between 2018 to 2019 and were identified as 19 families and 27 species. Parameter b ranged from 2.414 to 3.472. Thirteen species among 27 species showed isometric growth (b=3), six species showed negative allometry (b<3) and eight species showed positive allometry (b>3). The results of this study provide useful basic biological information about 27 fishes and are highly reliable due to use of data measured directly.

• Journal of Korean Academy of Nursing
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• v.52 no.4
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• pp.451-463
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• 2022

Purpose: This study examined the reciprocal relationships between depression and income, and gender differences in these relationships among older adults in South Korea. Methods: Using 2015 to 2019 of the Korea Welfare Panel Study (KoWePS), we studied 6,070 older adults (2,394 men and 3,676 women) aged 60 years over in 2015. The generalized estimating equation was employed to explore the effect of an individual income on depression and the reverse causal link-that of depression on income. Results: The study found the reciprocal relationships between income and depression. Income has a significant impact on depression. Higher-income was linked to decreased risks of the Center for Epidemiologic Studies Depression (CES-D) scores among older adults (B = - 0.121, p < 0.001). Estimates of the reverse causal link show that higher CES-D scores were also linked to income reduction among Korean older adults (B = - 0.007, p < 0.001). In addition, we also observed gender differences in the impact of income on depression but not in the reverse causal link. Income has more detrimental to psychological consequence for older men (B = - 0.108, p < 0.001) than older women (B = - 0.057, p < 0.001). Conclusion: The finding implies that both psychological and social protection policies for the elderly are needed in view of gender perspective.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.4
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• pp.11-20
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• 1993

In the new database applications such as office information systems, CAD/CAM, and AI, it is required to support not only fixed Is-A and Part-Of relationships but also various user-defined dynamic relationships including complicate constraints. However, existing object-oriented systems have many weaknesses in managing those complex relationships. This paper presents the Object-Oriented Relationship data Model (OORM) which is designed to provide facilities for modeling complex relationships into object oriented databases using abstraction concept. In the model, various integrity and consistency constraints related to the relationships can be also represented. And this paper presents a query language, ORSQL(Object Relationship SQL). ORSQL is a nonprocedural query language having similiar syntax to the standard SQL and supporting OORM's operations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.414-422
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• 2004

To infer phylogenetic relationships among Epinephelus species inhabiting coastal regions of Korean peninsula, mitochondrial cytochrome b genes from 9 species belonging to the subfamily Epinephelinae were PCR-amplified, cloned and sequenced. Aligned cytochrome b sequences of 10 species containing one additional sequence from GenBank were 1,140 base pairs in length, including 439 variable and 330 parsimony informative sites. The cytochrome b genes of 10 species, as other vertebrates studied to date, exhibit unequal base compositions: an entirely low G content ($15.2{\pm}0.3{\%}$on average) and almost equal T, C and A contents ($29.3{\pm}0.8{\%},\;30.7{\pm}1.0{\%},\;and\;24.8{\pm}0.5{\%}$ on average, respectively).In third codon positions, transitional substitutions especially between Epinephelus species and outgroup species are almost certainly saturated or near saturation. Phylogenetic analyses were performed with sequence data from 8 Epinephelus species and 2 outgroup species (Cephalopholis urodela and Vaviola louti) by using distance-based (neighbor-joining and minimum evolution) and parsimony-based (maximum parsimony) methods. The results showed that the monophyly of the genus Epinephelus was supported by relatively high bootstrap values. However, phylogenetic relationships among E. areolatus, E. moara, E. septemfasciatus, and Epinephelus sp were poorly resolved. Within the genus Epinephelus, three resolved monophyletic groups were found: clade 1 included E. akaara and E. awoara;, clade 2 included E. fasciatus and E. merra; and clade 3 included E. akaara, E. awoara, E. fasciatus, E. merra, E. areolatus, E. moara, E. septemfasciatus and Epinephelus Sp.