• Title/Summary/Keyword: Population origin

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On the origin of super-Helium-rich population in the Milky Way bulge

  • Kim, Jaeyeon;Han, Daniel;Lee, Young-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.66.4-67
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    • 2016
  • Our recent investigation (Lee et al. 2015) suggests that the presence of double red clump in the Milky Way bulge is another manifestation of multiple populations observed in halo globular clusters. The origin of Helium enhancement in the 2nd generation population (G2), however, is not yet fully understood. Here we investigate the origin of this super-Helium-rich population in the framework of self-enrichment scenario. We find that chemical enrichments and pollutions by asymptotic giant branch stars and winds of massive rotating stars can naturally reproduce the observed Helium enhancement. The Helium to metal enrichment ratio appears to be ${\Delta}Y/{\Delta}Z=6$ for G2, while the standard ratio, ${\Delta}Y/{\Delta}Z=2$, is appropriate for G1, which is probably enriched mostly by typeII supernovae.

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Rapid Origin Determination of the Northern Mauxia Shrimp (Acetes chinensis) Based on Allele Specific Polymerase Chain Reaction of Partial Mitochondrial 16S rRNA Gene

  • Kang, Jung-Ha;Noh, Eun-Soo;Park, Jung-Youn;An, Chel-Min;Choi, Jung-Hwa;Kim, Jin-Koo
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.4
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    • pp.568-572
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    • 2015
  • Acetes chinensis is an economically important shrimp that belongs to the Sergestidae family; following fermentation, A. chinensis' economic value, however, is low in China, and much of the catch in China is exported to Korea at a low price, thus leading to potential false labeling. For this reason, we developed a simple method to identify A. chinensis' origin using allele-specific polymerase chain reaction (PCR). Ten single nucleotide polymorphisms (SNPs) were identified from partial (i.e., 570 bp) DNA sequence analysis of the mitochondrial 16s rRNA gene in 96 Korean and 96 Chinese individual shrimp. Among 10 SNP sites, four sites were observed in populations from both countries, and two sites located in the middle with SNP sites at their 3'-ends were used to design allele-specific primers. Among the eight internal primers, the C220F primer specific to the Chinese A. chinensis population amplified a DNA fragment of 364 bp only from that population. We were able to identify the A. chinensis population origin with 100% accuracy using multiplex PCR performed with two external primers and C220F primers. These results show that the 16S rRNA gene that is generally used for the identification of species can be used for the identification of the origin within species of A. chinensis, which is an important finding for the fair trade of the species between Korea and China.

Characteristics of Morphological and Production from Different Origin of Foeniculum vulgare Mill.

  • Chung, Hae-Gon;Kim, Seong-Min;Nemeth, E.
    • Korean Journal of Medicinal Crop Science
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    • v.11 no.4
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    • pp.259-263
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    • 2003
  • This study was carried out to get basic information about the morphological and production characteristics of fennel populations different origin under different ecological conditions in Hungary. The Korean population can be registered as a medium high genotype and showed a more accelerated growth characters than Hungarian taxon and the two populations have a medium homogeneity $(CV\;=\;4{\sim}22%)$. In the second year plant height in Hungarian taxon was significantly higher than that of the Korean population. The shooting dynamic of individual plants might be heterogeneous in both taxa and the Korean population was not only shorter in the height but had also less shoots by 16% than the Hungarian one. The Hungarian taxon exceeded the umbel size and numbers to the Korean one (by 3.62 cm in the average) and the variability in the populations was high $(CV\;=\;29{\sim}49%)$. Seed size was proved to be also a discriminative feature between the examined taxa. With small deviations (CV < 2) the Hungarian population produced seeds longer by 38%. Homogeneity in the populations was dependent more on the vegetation years and on the characteristics measured but less on the origins, respectively.

A Study on Effects of Changes in the Optimal Population Density and Traffic Volume Impact of Urban Size (최적인구와 통행량분포가 도시규모의 변화에 미치는 영향에 관한 연구)

  • Yoo, Inhye
    • Journal of the Korean Regional Science Association
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    • v.31 no.1
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    • pp.21-42
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    • 2015
  • This paper investigates whether urban expansion and the vitalization of the local economy can be achieved through new city development. The results show that regardless of the starting point (origin) or destination point, traffic increases closer to the origin for the purpose of transportation and decreases farther from the origin. However, traffic tends to increase in districts 20 to 40 km away from the origin. Hence, building a new city in this district may be effective in terms of geography and functionality.

Association between I/D Polymorphism of Human LRPAP1 Gene and Body Mass Index in Korean General Population

  • Kang, Byung-Yong;Bae, Hak-Gyoon;Jhin, Hae-Kyung;Lee, Kyung-Soon;Lee, Kang-Oh
    • Toxicological Research
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    • v.19 no.3
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    • pp.205-210
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    • 2003
  • The aim of this study was to estimate the influence of 37 bp insertion/deletion (I/O) poly-morphism of the low density lipoprotein receptor-related protein-associated protein 1 (LRPAP1) gene on anthropometrical or biochemical parameters in korean general population. To determine the frequency of the genotype, we analyzed 244 samples of Korean origin. The frequency of the I allele was 0.55 in men and 0.56 in women, which were significantly higher than the frequency (0.26) that was reported in Czech population of Caucasian origin. In addition, the I allele of this polymorphism was significantly associated with higher value of body mass index (BMI) in our subjects by ANOVA test (P<0.05), and this association was maintained after controlling for age and gender by ANCOVA test (P<0.05). Thus, our results suggest that the I/O polymorphism of the LRPAP1 gene may be useful as a genetic marker for obesity in Korean general population.

Otolith microchemistry reveals the migration patterns of the flathead grey mullet Mugil cephalus (Pisces: Mugilidae) in Korean waters

  • Bae, Seung Eun;Kim, Jin-Koo
    • Journal of Ecology and Environment
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    • v.44 no.3
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    • pp.185-195
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    • 2020
  • Background: The flathead grey mullet Mugil cephalus has the widest distribution among mugilid species. Recent studies based on mitochondrial DNA sequences showed that the species comprises at least 14 different groups, three of which occur in the northwest Pacific. We analyzed the otolith microchemistry of M. cephalus at several locations in Korea to improve understanding of migration pattern and population origin. Results: We collected 123 sagittal otoliths from seven locations and determined their concentrations of eight elements (7Li, 24Mg, 55Mn, 57Fe, 60Ni, 63Cu, 88Sr, and 138Ba) using laser ablation inductively coupled plasma mass spectrometry. Mean otolith elemental ratios differed significantly among the locations. The Sr:Ca, Fe:Ca, and Ba:Ca ratios were significantly higher than others, and useful chemical signatures for investigating the habitat use of M. cephalus populations. We identified five diverse and complicated migration patterns using the otolith data that we collected: estuarine resident (type I), freshwater migrant (type II), estuarine migrant (type III), seawater resident (type IV), and seawater migrant (type V). A canonical discriminant analysis plot revealed separation of two groups (type II in the Yellow Sea vs. other types in remaining locations). Two locations on Jeju Island, despite their close proximity, had fish with quite different migration patterns, corroborating previous molecular studies that distinguished two groups of fishes. Conclusion: We successfully showed that the migration patterns of the Korean mullet varied by location. Only fish from the western sector of Jeju had a unique migration pattern, which is likely confined population in this area. Among the eight otolith elements measured, the Sr:Ca ratio was found to be the best indicator of migration pattern and population origin.

Migration Characteristics by the Regional Population Scale and Network Analysis of Population Movement Rate (인구 규모별 인구이동 특성과 인구이동률 네트워크 분석)

  • Lee, Jimin
    • Journal of Korean Society of Rural Planning
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    • v.24 no.3
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    • pp.127-135
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    • 2018
  • In countries and regions population plays an important role. Recently the importance of population migration increased as population growth slowed. Researches on population migration are mainly focused on the analysis of the population movement factors and the regional structure analysis using the network analysis method. Analysis of regional structure through population movement is not enough to explain the phenomenon of migration of small cities and rural regions. In this study, to overcome the limit of previous studies the characteristics of the population movement rate according to the size of the population were analyzed. Also network analysis using the population movement OD (Origin and Destination) and population movement rate OD were conducted and the results of them were compared. As the results of analysis by the regional population scale, the population movement by population size showed a big difference in the areas with more than 100 thousand people and less than 100 thousand people. Migration to the outside of the province was the most frequent in regions with 30,000~50,000 people. The population migration rate network analysis result showed that the new area with large population inflow capacity was identified, which could not be found in the population movement network analysis because population movement number is small. The population movement rate irate is expected to be used to identify the central regions of the province and to analyze the difference in resident attractiveness.

The Origin of the Type III Component in the Black Eye Galaxy M64

  • Kang, Jisu;Kim, Yoo Jung;Lee, Myung Gyoon;Jang, In Sung
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.52.2-52.2
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    • 2021
  • The Black Eye Galaxy M64 is an intriguing spiral galaxy with a Type III disk break. To trace the origin of its Type III component, we present HST/ACS F606W/F814W photometry of resolved stars in the outer disk of M64 (2.5' < R < 6.5'). First, we discover a bright extended globular cluster (GC) M64-GC1 at R ~ 5.5', and find that it is an old metal-poor halo GC ([Fe/H] = -1.5 +/- 0.2). Second, we find that there are two distinct subpopulations of red giant branch stars (RGBs). One is an old metal-rich ([Fe/H] ~ -0.4) disk population, and the other is an old metal-poor halo population similar to the resolved stars in M64-GC1. The radial number density profile of the metal-rich RGB follows an exponential disk law, while that of the metal-poor RGB follows a de Vaucouleurs's low. From these results, we conclude that the origin of the Type III component in M64 is a halo, not a disk or a bulge. We will further discuss the results in regards to the formation and evolution of M64.

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Study on Origin and Phylogeny Status of Hu Sheep

  • Geng, R.Q.;Chang, H.;Yang, Z.P.;Sun, W.;Wang, L.P.;Lu, S.X.;Tsunoda, K.;Ren, Z.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.5
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    • pp.743-747
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    • 2003
  • Applying simple random sampling in typical colony methods in the central area of habitat, 14 structural loci and 31 alleles in blood enzyme and other protein variations of Hu sheep population are examined. After collecting the same data of 11 loci about the 22 sheep colonies in China and other countries, it clusters the 23 sheep populations by fuzzy cluster analysis. The study proves that the phylogenetic relationship between Hu sheep population and Mongolia populations is relatively closed. This result obtained is shown to conform to the historical data.

On the Origin of the Correlation between Hubble Residual and Mass of the Type Ia Supernova Host Galaxies

  • Kang, Yijung;Kim, Young-Lo;Lim, Dongwook;Chung, Chul;Lee, Young-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.36.1-36.1
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    • 2014
  • The correlation between mass of Type Ia Supernova (SN Ia) host galaxies and Hubble residual is now well-established. The origin of this relation, however, is yet to be understood. We have used low-resolution spectra of early-type hosts from YONSEI (YOnsei Nearby Supernovae Evolution Investigation) project to measure central velocity dispersion and Lick/IDS absorption indices. By using the Evolutionary Population Synthesis (EPS) models, luminosity-weighted mean age and metallicity of host galaxies were determined from $H{\beta}$ and absorption lines. Here we will discuss the correlation between the velocity dispersion, which indicates the mass of galaxies, and mean age of stellar population in our sample of early-type host galaxies.

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