• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.46.1-46.1
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• 2017

Class I methanol masers are found to be good tracers of the interaction between outflows from massive young stellar objects with their surrounding media. Although polarization observations of Class II methanol masers have been able to provide information about magnetic fi elds close to the central (proto)stars, polarization observations of Class I methanol masers are rare, especially at 44 and 95GHz. We present the results of linear polarization observations of 39 Class I methanol maser sources at 44 and 95GHz. These two lines are observed simultaneously with one of the 21m Korean VLBI Network telescopes in single-dish mode. Approximately 60% of the observed sources have fractional polarizations of a few percent in at least one transition. This is the fi rst reported detection of linear polarization of the 44GHz methanol maser. We also observed 7 targets with the KVN in VLBI mode. We will present its preliminary results, too.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.142.1-142.1
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• 2011

UBVI and $H{\alpha}$ CCD photometry of IC 1848, one of active star-forming regions in Cas OB6, is carried out as a part of Sejong Open cluster Survey (SOS) project. An OB association is an ideal laboratory for studying the triggered star formation and star formation history. Our purposes are to provide deep photometric data up to 21 mag in V and physical parameters of IC 1848. We classify 79 early-type stars and 186 pre-main sequence (PMS) stars as being the members of the cluster using photometric criteria. The IR excess emission PMS stars by Koenig et al. (2008) are also included as members of IC 1848. Total number of members is 414. We derive the interstellar reddening (=$0.659{\pm}0.058$ mag), reddening law ($R_V=4.0{\pm}0.1$), distance modulus ($V_0-M_V=12.0{\pm}0.1$ mag) using the early-type members of IC 1848. We also determine the age of the cluster ($3.5{\pm}1.5$ Myr) by placing the theoretical isochrones on the HR diagram.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.88.1-88.1
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• 2011

Shocks are thought to be important in the dynamics and heating of the solar chromosphere. The observational determination of shock parameters, however, has been hardly done because of the difficulty of observation at a high spatial, temporal and spectral resolution, and the lack of an effective method of inferring physical parameters from spectral data. Our inversion of the spectral data of the $H{\alpha}$ and Ca II 854.2 nm lines simultaneously taken from an intranetwork area, produced temporal profiles of temperature as well as line-of-sight velocities, from which we infer that three-minute chromospheric oscillations prevailing in the upper chromosphere are in fact trains of strong shocks with a strength of about two and a propagation speed of 20 km s-1 that carry a mechanical energy flux of 500 W m-2 upward. Our result supports the notion that shocks dominate the heating of the upper chromosphere, and probably the corona as well, at least in intranetwork regions of the quiet sun.

• Journal of Environmental Health Sciences
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• v.3 no.1
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• pp.4-8
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• 1976

Authors investigated the hematological examinations of 993 persons at rural region among the 1,7 41 of residents in-the part of Dang Jin (M:268, F:247) and Young Joo (M:270, F:208) in the Korea which was indicated as follows. 1. Average value and standard deviation of hematological items represents as follows: i) Hemoglobin Men Dang Jin-13.99$\pm$0.52. Man Young Joo-14.93$\pm$0.57 Women Dang Jin-12.56$\pm$0.38 women Young Joo-13.65$\pm$0.48 ii)Hematocrit Men Dang Jin-42.68$\pm$1.09 Man Young Joo-44.61$\pm$1.42 Women Dang Jin-38.16$\pm$0.93 women Young Joo-40.33$\pm$1.27 iii) Mean Corpuscular hemoglobin concentration Men Dang Jin-32.79$\pm$1.06. Man Young Joo-33.46$\pm$0.36 Women Dang Jin-32.92$\pm$0.75 women Young Joo-33.83$\pm$0.82 iv) WBC Men Dang Jin-7.130$\pm$880. Man Young Joo-7.490$\pm$910 Women Dang Jin-6.030$\pm$1.150 women Young Joo-7.320$\pm$1.040 2. The aspect of blood type at Young Joo and Dang Jin was same indicated in the order of A,O,B, and AB. 3. There are higher values of hemoglobin, hernatocrit, M.C.H.C. and WBC in men and women at Young Joo than Dang Jin.

• Molecules and Cells
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• v.37 no.1
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• pp.43-50
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• 2014

Jumonji domain-containing proteins (JMJD) catalyze the oxidative demethylation of a methylated lysine residue of histones by using $O_2$, ${\alpha}$-ketoglutarate, vitamin C, and Fe(II). Several JMJDs are induced by hypoxic stress to compensate their presumed reduction in catalytic activity under hypoxia. In this study, we showed that an H3K27me3 specific histone demethylase, JMJD3 was induced by hypoxia-inducible factor (HIF)-$1{\alpha}/{\beta}$ under hypoxia and that treatment with Clioquinol, a HIF-$1{\alpha}$ activator, increased JMJD3 expression even under normoxia. Chromatin immunoprecipitation (ChIP) analyses showed that both HIF-$1{\alpha}$ and its dimerization partner HIF-$1{\beta}$/Arnt occupied the first intron region of the mouse JMJD3 gene, whereas the HIF-$1{\alpha}/{\beta}$ heterodimer bound to the upstream region of the human JMJD3, indicating that human and mouse JMJD3 have hypoxia-responsive regulatory regions in different locations. This study shows that both mouse and human JMJD3 are induced by HIF-1.

• Journal of The Korean Astronomical Society
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• v.36 no.4
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• pp.271-282
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• 2003

We present results of a $H^{13}CN$ J=1-0 mapping survey of molecular clouds toward the Galactic Center (GC) region of $-1.6^{\circ}{\le}{\iota}{\le}2^{\circ}$ and $-0.23^{\circ}{\le}b{\le}0.30^{\circ}$ with 2' grid resolution. The $H^{13}CN$ emissions show similar distribution and velocity structures to those of the $H^{12}CN$ emissions, but are found to better trace the feature saturated with $H^{12}CN$ (1-0). The bright components among multi-components of $H^{12}CN$ line profiles usually appear in the $H^{13}CN$ line while most of the dynamically forbidden, weak $H^{12}CN$ components are seldom detected in the $H^{13}CN$ line. We also present results of other complementary observations in $^{12}CO$ (J=1-0) and $^{13}CO$ (J=1-0) lines to estimate physical quantities of the GC clouds, such as fractional abundance of HCN isotopes and mass of the GC cloud complexes. We confirm that the GC has very rich chemistry. The overall fractional abundance of $H^{12}CN$ and $H^{13}CN$ relative to $H_2$ in the GC region is found to be significantly higher than those of any other regions, such as star forming region and dark cloud. Especially cloud complexes nearer to the GC tend to have various higher abundance of HCN. Total mass of the HCN molecular clouds within $[{\iota}]{\le}6^{\circ}$ is estimated to be ${\~}2 {\times}10^7\;M_{\bigodot}$ using the abundances of HCN isotopes, which is fairly consistent with previous other estimates. Masses of four main complexes in the GC range from a few $10^5$ to ${\~}10^7\;M_{\bigodot}$ All the HCN spectra with multi-components for the four main cloud complexes were investigated to compare the line widths of the complexes. The largest mode (45 km $s^{-1}$) of the FWHM distributions among the complexes is in the Clump 2. The value of the mode tends to be smaller at the farther complexes from the GC.

• Journal of Radiation Protection and Research
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• v.30 no.4
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• pp.237-245
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• 2005

The distribution of radionuclides in soil and plants were calculated, assuming an accidental release of radionuclides from Yeonggwang Nuclear Power Plant. The results which show the concentration change with time and regions were displayed by GIS. GIS Included the commercial program, ArcView(ESRI), and a basic digital map of 1:5000 scale for 30km by 30km area around Yeonggwang Nuclear Power Plant. The target material was $^{137}Cs$ in soil around Yeonggwang area. Given denosited $^{137}Cs$ concentrations, ECOREA-II code computed the $^{137}Cs$ concentration of the soil and the plant in the area divided by 16 azimuth, 480 unit cells in total in which the concentrations also varied with time. The results were introduced into the attributed data of previously designed polygon cells in ArcView. In order to display the concentration change with time by monotonic color, the RGB value for ArcView color lamp was controlled. This display is useful for the public to understand the concentration change of radionuclide around Yeonggwang area definitely.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.496-502
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• 2005

The chemical properties and nitrite scavenging ability were analyzed which on a citron (Citrus junos) of 4 kinds purchased in different regions [Namhae (I, II), Tongyoung and Koheung] in Korea. Four kinds of organic acids were determined. Citric acid contents in flesh and peel of citron were $10.2\pm0.14\~17.7\pm0.17\;g/100g$. The organic acid content was the highest in citron purchased from Koheung. Total mineral content in citron was in a range of $2,844.3\~4,022.4$ mg/100 g, the potassium content was the highest in the range of $1,332.4\pm2.31\~2,308.5{\pm}3.25\;mg/l00g$. The major free amino acid from citron were proline, asparagine and glutamic acid. And the highest in peel of citron purchased from Tongyoung by 326.9 mg/100 g. However, the kinds and contents of chemical components in citron were somewhat different among various regions. The electron donating ability using DPPH method of citron juice was more than $80.0\%$ at the concentration of $0.1\~0.2\%$ and it was stronger by increased the juice concentration in the reaction mixture. SOD-like activity showed $10.2\pm0.50\~20.1\pm0.77\%$ at the concentration of $0.01\~0.2\%$. The nitrite scavenging ability was pH and sample concentration dependent. It was the highest at the pH 1.2 and more than $73\%$ in $0.1\~0.2\%$ citron juice. On the contrary in all concentration of added citron juice lower than $27\%$ at pH 4.2.

• Journal of Astronomy and Space Sciences
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• v.22 no.4
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• pp.419-430
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• 2005

We have carried out a statistical analysis on solar wind dynamic pressure pulses during geomagnetic storms. The Dst index was used to identify 111 geomagnetic storms that occurred in the time interval from 1997 through 2001. We have selected only the events having the minimum Dst value less than -50 nT. In order to identify the pressure impact precisely, we have used the horizontal component data of the magnetic field H (northward) at low latitudes as well as the solar wind pressure data themselves. Our analysis leads to the following results: (1) The enhancement of H due to a pressure pulse tends to be proportional to the magnitude of minimum Dst value; (2) The occurrence frequency of pressure pulses also increases with storm intensity. (3) For about $30\%$ of our storms, the occurrence frequency of pressure pulses is greater than $0.4\#/hr$, implying that to. those storms the pressure pulses occur more frequently than do periodic substorms with an average substorm duration of 2.5 hrs. In order to understand the origin of these pressure pulses, we have first examined responsible storm drivers. It turns out that $65\%$ of the studied storms we driven by coronal mass ejections (CMEs) while others are associated with corotating interaction regions $(6.3\%)$ or Type II bursts $(7.2\%)$. Out of the storms that are driven by CMEs, over $70\%$ show that the main phase interval overlaps with the sheath, namely, the region between CME body and the shock, and with the leading region of a CME. This suggests that the origin of the frequent pressure pulses is often due to density fluctuations in the sheath region and the leading edge of the CME body.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.155-160
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• 2008

Several studies have reported quantitative trait loci (QTL) for meat quality on porcine chromosome 2 (http://www.animalgenome.org/QTLdb/pig.html). For application of the molecular genetic information to the pig industry through marker-assisted selection, single nucleotide polymorphism (SNP) markers were analyzed by comparative re-sequencing of polymerase chain reaction (PCR) products of 13 candidate genes with DNA from commercial pig breeds such as Berkshire, Yorkshire, Landrace, Duroc and Korean Native pig. A total of 34 SNPs were identified in 15 PCR products producing an average of one SNP in every 253 bp. PCR restriction fragment length polymorphism (RFLP) assays were developed for 11 SNPs and used to investigate allele frequencies in five commercial pig breeds in Korea. Eight of the SNPs appear to be fixed in at least one of the five pig breeds, which indicates that different selection among pig breeds might be applied to these SNPs. Polymorphisms detected in the PTH, CSF2 and FOLR genes were chosen to genotype a Berkshire-Yorkshire pig breed reference family for linkage and association analyses. Using linkage analysis, PTH and CSF2 loci were mapped to pig chromosome 2, while FOLR was mapped to pig chromosome 9. Association analyses between SNPs in the PTH, CSF2 and FOLR suggested that the CSF2 MboII polymorphism was significantly associated with several pork quality traits in the Berkshire and Yorkshire crossed F2 pigs. Our current findings provide useful SNP marker information to fine map QTL regions on pig chromosome 2 and to clarify the relevance of SNP and quantitative traits in commercial pig populations.