• Journal of The Korean Astronomical Society
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• v.29 no.1
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• pp.9-18
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• 1996

We have analyzed vector magnetograms and $H\beta$ filtergrams of two sunspot groups, one in a growing phase and the other in a decaying phase. In this study, the temporal evolution of their magnetic morphology has been investigated in association with solar activity. The morphological variations of the growing and decaying phase of these sunspots revealed in detail the coalescence of small spots into a large spot and the fragmentation of a large spot into many small spots, respectively. Numerous small flares were detected in the spot group during the decaying phase. This seems to be intimately associated with the shearing motions of many spots with different polarities created by fragmentation of a large sunspot. The magnetic flux and the average shear angle are found to be substantially reduced during the decaying phase, especially in the course of the flarings. This implies that the decaying phase of the sunspot is, to some degree, involved with magnetic field cancellation. The growing spot group has not shown any large activities, but numerous small spots have grown into a typical bipolar sunspot.

• Journal of The Korean Astronomical Society
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• v.26 no.2
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• pp.89-98
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• 1993

Magnetostatic models of starspots of late type main sequence stars$(G5V\~K5V)$ have been constructed to investigate their physical characteristics by using the similarity law suggested by Schluter and Temesvary(1958) and later employed by Deinzer(1965) and Yun(1968). The starspots are assumed to be single, circular and in horizontal magnetostatic equilibrium. In the present study we considered only those model spots whose area covers less than $12\%$ of the entire stellar surface as suggested by observations. The computed surface field strength of our model spots ranges from $10^3$\;to\;several\;10^3$ gauss and their magnetic flux is found to be $10\~100$ times that of sunspots. The field strength is sensitive to spectral type, which increases with later spectral type. In contrast to the field strength, the area of starspots depends strongly on the total magnetic flux. Finally, it is noted that the computed field strength of model spots belonging to $G0V\~G5V$ falls below the equipartition field strength at their parent stellar surface unless the coverage is less than $2\%$. This suggests that the observed spot on $G0V\~G5V$ stars is likely to be a group of small starspots.

• Child Health Nursing Research
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• v.12 no.1
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• pp.75-83
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• 2006

Purpose: This study was done to verify the effect of roller acupuncture stimulation on baesu spots of joktaeyang bangkwang kyeong in the reaction to physiologic pain(heart rate, percutaneous oxygen saturation, respiration rate) in neonates. Method: This study was a nonequivalent control group non-synchronized design. The participants were 40 normal neonates who were born at a hospital in Busan. These neonates were undergoing heel puncture for blood type tests. The neonates were divided into 2 groups: 20 in the experimental group who were stimulated with roller acupuncture before the heel puncture and 20 neonates in the control group who were not stimulated. The heart rate and percutaneous oxygen saturation were measured using a cardiopulmonary monitor and the respiration rate was measured directly. The data were analyzed with SPSS 10.0 program using χ²-test, t-test and Repeated Measure ANOVA. Results: There was a significant difference (F=3.287, p=.043) for heart rate on the interaction between time and group. There was a significant difference (F=5.122, p=.008) for percutaneous oxygen saturation on the interaction between time and group. Conclusion: On the basis of results, it was verified that the roller acupuncture stimulation on baesu spots of joktaeyang bangkwang kyeong had effect of relieving pain in the neonates.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.122-122
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• 2017

Wheat wild relatives that have never been domesticated contained useful genetic resources such as the resistance to abiotic and biotic stresses. Leymus racemosus is one of the wild species. It can grow in a harsh environment like seaside and distribute by healthy rhizomes. Also, it has a useful genetic resource such as salt tolerance and different diseases resistance. Wheat (Triticum aestivum L. cv. Chinese Spring; CS) was crossed with L. racemosus. Wheat-L. racemosus disomic addition lines were produced. The purpose of this study is to identify protein expression in each disomic addition line compared to CS. We performed two-dimensional electrophoresis. Two-dimensional gels stained with coomassie brilliant blue (CBB), a total of 1566 differentially expressed proteins were identified by Progenesis Same Spots software from the cultivars. However, a total of 90 protein spots were identified to be either present or absent or showing significantly differential expression when the difference threshold was set to more than 1.5 fold. However, out of the 90 differentially protein spots, a total of 74 spots were sorted for mass spectrometry analysis. The identified proteins may provide important clues for better understanding the molecular changes in the chromosomes carrying Leymus racemosus.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.73-78
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• 1997

A virus was purified from Korean cactus (Chamaeaereus silverstrii f. Variegata Hort) showing necrotic spots and its biophysicochemical properties were examined. The typical necrotic spots were observed on healthy looking cactus inoculated with the purified virus and the various symptoms from necrotic spots to systemic were observed on 17 species of test plats used, which suggests that the purified virus has the normal infectivity and wide host range. Ultraviolet absorption scanning analysis revealed that the viral preparation had the typical curve with shoulder at 290 nm and its ratio of absorbances at 260 nm to 280 nm and extinction coefficient was 1.156 and 2.86, respectively. The virus represented one distinct and homogeneous band and molecular weight of viral coat protein was determined to 17, 000 Dalton by SDS-PAGE. The virus revealed rod-shaped virion (325$\times$20 nm) by electron microscopy. Based on these results, it has been thought that the virus purified in this study is the pathogenic agents causing necrotic spot symptom on Korean cacuts and one of the member of tobamovirus family.

• Reproductive and Developmental Biology
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• v.34 no.2
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• pp.73-79
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• 2010

We investigated the microtubule dynamics, including the inheritance of donor centrosomes and the mitotic spindle assembly occurring during the first mitosis of somatic cell nuclear transfer (SCNT) embryos in pigs. SCNT embryos were fixed 15 min and 1 h after fusion in order to assess the inheritance pattern of the donor centrosome. The distribution and dynamic of the centrosome and microtubule during the first mitotic phase of SCNT embryos were also evaluated. The frequency of embryos evidencing $\gamma$-tubulin spots (centrosome) was 93.2% in the SCNT embryos 15 min after fusion. In the majority of the SCNT embryos (61.5%), however, no centrosome was observed 1 h after fusion. The frequency of the embryos with no or abnormal mitotic spindles 20 h after fusion was 19.6%. The $\gamma$-tubulin spots were detected near the nuclei of somatic cells regardless of cell cycle phase, whereas $\gamma$-tubulin spots in the SCNT embryos were observed only during the inter-anaphase transition. These results showed that the donor centrosome is inherited into the SCNT embryos, but failed to assemble the normal mitotic spindles during first mitotic phase in some SCNT embryos.

• The Korean Journal of Zoology
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• v.4 no.1
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• pp.29-31
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• 1961

At the altitude of approximately 250 of Mt. Sori located in Kyung-gi Co, Korea authers have made a field collection of Drosophila during June, 1 and 15, 1961, and found about 30 specimens which seemed to be a new species belonging to Genus Drosophila, Subgenus Hirtodrosophila. AUthors have named the species : D. macromaculata sp. nov. " Its Korean name is given , : Uluck-muni-chopari". This species is very similar to Drosophila cheda in its external feature and especially it that each of four stripes in the mesonotum is cut into tow, and it also resembles with Drosophila calloptera in that it has three distinct spots in the wing. Its first segment of abdomen is yellow-brown in color while both end points are black. The second segment is black and in its middle part there yellow-brownish strips of V form, the peripheral part of which are found two spots of yellow brownish color. On third to fifth segments of male and on third to sixth segments of female there are fod-form spots, one on each segment, and on both sides of these rods two smaller spots are found in each segment. This species is clearly a fungus feeder and its breeding in authers laboratory is at present, not attained. Holotype : male , Kwang-nung, Kyung -gi Do, South Korea, 1 Male June, 1, 1961. Allotype : female, collected together with holotype. Paratype : Kwang-nung, Male 16 and female 12. Distribution : South Korea. Collecting method : Net sweeping on the decayed trees.yed trees.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1499-1512
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• 2006

Based on the first 2D reference map of the fission yeast Schizosaccharomyces pombe protein reported previously, we expanded and updated the map using narrower pI ranges. In this paper, 240 protein spots were identified on our reference map. In the pI 4-7 range, 144 spots corresponding to 86 different proteins were identified. In the pI 6-9 range, 43 spots corresponding to 35 different proteins were identified. Fifty-three new spots corresponding to 39 different proteins were further identified in the pI 5-6 range.

• The Korean Journal of Mycology
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• v.45 no.1
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• pp.54-62
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• 2017

In 2014, abnormal brown spots were observed on Hongro apples in fields in Gyeongsangbuk-do Province and during low-temperature storage. The spots were round, blight brown, and different from the symptoms of previously reported apple diseases. A fungal pathogen was isolated and cultured on potato dextrose agar, and it was morphologically similar to Fusarium decemcellulare. A pathogenicity test showed the same brown spots on both wounded and unwounded Hongro and Fuji apple cultivars. RPB1 and RPB2 sequences of F. decemcellulare KNU-GC01 matched with those of F. decemcellulare NRRL 13412 (98.3% and 97.6% similarities, respectively); both strains clustered together in the phylogenetic tree, indicating their close relationship at the species level. Therefore, F. decemcellulare is a newly reported pathogen that causes brown spots on apples in Korea.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.788-793
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• 2018

High-density spent fuel (SF) storage racks have been installed to increase SF pool capacity. In these SF racks, neutron absorber materials were placed between fuel assemblies allowing the storage of fuel assemblies in close proximity to one another. The purpose of the neutron absorber materials is to preclude neutronic coupling between adjacent fuel assemblies and to maintain the fuel in a subcritical storage condition. METAMIC neutron absorber has been used in high-density storage racks. But, neutron absorber materials can be subject to severe conditions including long-term exposure to gamma radiation and neutron radiation. Recently, some of them have experienced degradation, such as white spots on the surface. Under these conditions, the material must continue to serve its intended function of absorbing neutrons. For the first time in Korea, this article uses a neutron attenuation test to examine the performance of METAMIC surveillance coupons. Also, scanning electron microscope analysis was carried out to verify the white spots that were detected on the surface of METAMIC. In the neutron attenuation test, there was no significant sign of boron loss in most of the METAMIC coupons, but the coupon with white spots had relatively less B-10 content than the others. In the scanning electron microscope analysis, corrosion material was detected in all METAMIC coupons. Especially, it was confirmed that the coupon with white spots contains much more corrosion material than the others.