• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.202-202
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• 2022

Recently days, soybean production in paddy field is increasing, from 4,422 ha in 2016 to 10,658 ha in 2021 in Korea. It is easy for Phytophthora stem and root rot (PSR) occurring in paddy field condition, when it is poorly drained soils with a high clay content, and temporary flooding and ponding. Therefore PSR resistant soybean cultivar is required. The objective of this study is to identify QTL region and candidate genes relating to PSR resistance of the race in main soybean cultivation area in Korea. 210 soybean materials including cultivars and germplasm were used for inoculation and genome-wide association study (GWAS). Inoculation was conducted using stem-scar method with 2 replications in 2-year for the race 3053 from Kimje and 3617 from Andong. 210 materials were genotyped with Soya SNP 180K chip, and structure analysis and association mapping were conducted with QTLMAX V2. The results of inoculation showed that survival ratio ranged from 0% to 96.7% and mean 9.7% for 3053 and ranged from 0% to 100% and mean 7.6% for 3617. Structure analysis showed linkage disequillibrium (LD) was decayed below r²=0.5 at 335kb of SNP distance. Significant SNPs (LOD>7.0) were identified in Chr 1, 2, 3, 4, 5, 11, 14, 15 for 3053 and Chr 1, 2, 3, 7, 10, 14 for 3617. Especially, LD blocks (AX-90455181;15,056,628bp~AX-90475572;15,298,872bp) in Chr 2 for 3053 and 3067 were duplicated. 29 genes were identified on these genetic regions including Glyma.02gl47000 relating to ribosome recycling factor and defense response to fungus in Soybase.

• Journal of Life Science
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• v.25 no.12
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• pp.1354-1361
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• 2015

This study was aimed to investigate the distribution status and phylogenetic relationship of Myotis aurascens in Jeju Ialnd, which has not clearly confirmed until now. We found three groups of M. aurascens from three different cave enforcements (CEs). The bat population of Jeju Island had smaller levels of HBL and Hfcu, but greater levels of TL, EL, FAL, and Tra than those of the Korean Peninsula population. Jeju bats had wide range in the lengths of FAL and Hfcu comparing to those of European bats. From the bimonthly monitoring to each finding site, we have actually failed to observe those again, estimating that they use those CEs as the daily-roosting place in activating seasons. The sequences of CYTB and COI genes showed identical sequences among Jeju bats tested, indicating that they are maternally related. The results from molecular phylogeny showed that the sequences of these bats located on the same branch with those for M. aurascens in the phylogenetic trees. Besides, the nucleotide sequences of the Jeju bats showed the closest relation with that of Korean Peninsula. Consequently, these findings indicate that the bats of M. aurascens, verified the natural distribution in Jeju Island, have originated from a single maternal origin and differences in morphological and genetic backgrounds form those of Korean Peninsula and the other countries, and had probably immigrated via Korean Peninsula. These findings will contribute as basic information for understanding the migration history and biogeographic relationship of mammals on Jeju Island in East Asia.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.74-82
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• 2014

A perennial plant species of Ranunculaceae, Pulsatilla tongkangensis is a very rare species only found in limestone vegetation of South Korea. It is not only rare but also has great value as a horticultural resource, thus resulting in serious problems of overexploitation and habitat disturbance. For the conservation of the rare species and its development as a resource, the study was conducted with the following three aims: first, to investigate any new geographical distribution of the species; second, to identify the site condition and vegetation structure of its habitat; and third, to compare the ecology of P. tongkangensis in other microhabitats such as rock, slope and ridge area. A new distribution was found in limestone vegetation at Danyang-gun, Chungcheongbuk-do. It was, therefore, confirmed that the distribution of P. tongkangensis exactly coincides with the area of distribution of limestone, indicating a possibility that the species might be a calcicole. 87% of the microhabitats found in rocks. Compared to P. tongkangensis, at ridges or slopes, number of P. tongkangensis plants were few in rocks. It is possibly due to the lack of microhabitats that could settle in rocky areas. Once established on rocks, however, plants grew large enough to flower with higher number of leaves and flowers per plant, resulting in higher flowering rate on rocky areas. Cracks in/between rocks are likely to be safe places for the plants with favorable light conditions, abundant fine particles to root down and reduced competition for resources. Yet, further research is necessary in terms of determining whether the species is indeed a calcicole, whether other limiting factors work in its establishment stage, and genetic diversity exists in the population.

• Korean Journal of Cognitive Science
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• v.11 no.2
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• pp.37-51
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• 2000

The present study compared computer users target-selection response patterns when the targets were varied in terms of their relative location and distance from the current position of the cursor. In Experiment 1, where the mouse was used as an input device, the effects of different directions and distances of simple target(small rectangle) on target-selection response were investigated. The results of Experiment 1 can be summarized as follows: (1) Overshooting was more frequent than either undershooting or correct movement and (2) this tendency was more prominent when the targets were presented in the oblique direction or in farther location from the current cursor position. (3) Although the overshooting and undershooting were more frequent in the oblique direction, the degree of deviation was larger in horizontal and vertical direction. (4) Time spent in moving the mouse rather than that spent in planning, calibrating or clicking was found to be the most critical factor in determining total response time. In Experiment 2, effects of the font size and line-height of the target on target-selection response were compared with regard to two types of input devices(keyboard vs. mouse). The results are as follows: (1) Mouse generally yielded shorter target-selection time than keyboard. but this tendency was reversed when the targets were presented in horizontal and vertical directions. (2) In general, target-selection time was the longest in the condition of font size of 10 and line-height of 100%, and the shortest in the condition of font size of 12 and line-height of 150%. (3) When keyboard was used as the input device, target-selection time was shortest in the 150% line-height condition, whereas in the mouse condition, target-selection time tended to be increased as the line-height increased. which resulted in the significant interaction effect between input device and line-height. Finally, several issues relating to human-computer interaction were discussed based on the results of the present study.

• The Journal of the Petrological Society of Korea
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• v.9 no.2
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• pp.84-98
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• 2000

Daejeon-sa basalt in the Mt. Juwang area composed of 12 basalt flows alternate with 9 peperites and each basalt and peperite has the variety of thickness. Peperites yielded in Daejeon-sa basalt are mixed of basalt with reddish shale, of which textural type is globular peperite. Basalts yielded in Daejeon-sa basalt are massive basalt without vesicule, although sometimes vesicules are founded in upper within a flow unit. The basalt has mainly pseudomorph of olivine as phenocryst, and also plagioclase and clinopyroxene phenocryst. Matrix is mainly subophitic texture. The plotting result on the TAS diagram shows these basalts belong to the sub-alkaline, and it can be subdivided into calc-alkaline series on the basis of the diagram of Si02 vs. K20 and of alkali index vs. A1203 diagram. According to plots of wt.% oxides vs. wt.% MgO, abundances of A1203 and CaO increase with decreasing MgO while F ~ dOecre~ase . With decreasing MgO compatible elements decrease while incompatible elements increase. In spider diagram of MORB-normalized trace element patterns, HFS elements are nearly similiar with MORB, but LIL elements are enriched. Especially, contents of Ce, F: and Sm are enriched but Nb is depleted. In the chondrite-normalized REE patterns light REEs are enriched than heavy REEs. Tectomagmatic discrimination diagrams shows basalts in the study area are formed in the tectonomagmatic environment of subduction zone under continental margin. This result accord with characters of chemical composition mentioned above. Cr vs. Y diagram and CeM, vs. Ce diagram show that the primary magma of the basalts may formed by the about 15% partial melting of garnet-peridotite in the mantle wedge. After then, Daejeon-sa basalts may formed from evolved magma undergone mainly olivine fractional crystallization and contarnination of crustal materials before eruption.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.339-352
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• 2014

The study was carried out to analyze vegetation structure of Pinus densiflora and Quercus mongolica forests located in Jochimryeong to Shinbaeryeong of the Baekdudaegan mountain range. The survey for 50 plots was conducted from April 2012 to August 2013 in the permanent plots ($100m{\times}100m$) using phytosociological analysis. As a result, the vegetations were classified into five vegetation units. In species composition, they were classified into Q. mongolica community group divided into 2 community such as Fraxinus rhynchophylla community and Carpinus cordata community, F. rhynchophylla community was subdivided Pinus densiflor group (into Euonymus sachalinensis subgroup, Vitis coignetiae subgroup) and Juglans mandshurica group. C. cordata community was subdivided Acer komarovii group and Betula ermanii group. In terms of importance value, P. densiflora and Q. mongolica were more than 20% respectively. P. densiflora was found to have the highest relative coverage. Analysis of interspecific association showed four types which were coincident with differential species and character species on the constancy table. Based on the diameter class distribution, P. densiflora forest presented a normal distribution pattern except for other species which showed a reverse Jshaped distribution pattern, therefore P. densiflora forest would likely be replaced by Q. mongolica forests. While in Q. mongolica forest, diameter class distribution of all species population presented a reverse J-shaped distribution pattern, therefore Q. mongolica forest could likely remain in the future.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.303-310
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• 2011

Phylogenetic relationships of Jeju dogs to other domestic and foreign dog breeds were assessed using mtDNA D-loop sequences. Neighbor-joining trees were constructed using complete sequences (970 bp excluding the tandem repeat region) determined for five Cheju, four Jindo, four Sapsaree, five Pungsan, two of each East and West Laika dogs (Canis familiaris), two gray wolves (Canis lupus) and two coyotes (Canis latrans) and also published complete sequences for dogs. Coyote sequences were used as outgroups. In addition, a total of 214 haplotypes of 598bp D-loop sequences from 30 dog breeds were collected from GenBank and used to investigate genetic structure of population. In the analyses of full D-loop sequence variation and the phylogenetic trees constructed by neighbor-joining method, neither haplotypes nor clades specific for any domestic dog breeds were observed. The inter-species sequence variation (4.51%) between domestic dogs and wolves was much higher than the intra-species sequence variation within domestic dogs (1.63%) and wolves (3.64%). The divergence of the dog and wolf occurred approximately 1~2 million years ago based on these values. The taxa of Jeju dog breed in the phylogenetic tree are clustered separately and intermingled with other taxa of breeds, suggesting that active crossbreeding of Jeju dogs with other domestic breeds.