• Title/Summary/Keyword: Japanese population

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Population Analysis of Korean and Japanese Toxic Alexandrium catenella Using PCR Targeting the Area Downstream of the Chloroplast PsbA Gene

  • Kim Choong-Jae;Kim Chang-Hoon;Sako Yoshihiko
    • Fisheries and Aquatic Sciences
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    • v.7 no.3
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    • pp.130-135
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    • 2004
  • The marine dinoflagellate genus Alexandrium, which produces PSP toxins, has a global distribution. As human-assisted dispersal of the species has been suggested, it is important to develop molecular tools to trace the dispersal pathway. To screen population-specific DNA sequences that differentiate Korean and Japanese A. catenella, we targeted the area downstream of the chloroplast psbA gene using PCR with population-specific DNA primers followed by RFLP (restriction fragment length polymorphism) analysis and sequencing. The RFLP patterns of the PCR products divided Korean and Japanese A. catenella regional isolates into three types: Korean, Japanese, and type CMC3, isolated from Korea. We sequenced the PCR products, but found no similar gene in a homology search. The molecular phylogeny inferred from the sequences separated the Korean and Japanese A. catenella strains, as did the RFLP patterns. However, the Japanese isolates included two slightly different sequences (types J and K), while the Korean sequence was the same as the Japanese K type. In addition, a unique sequence was found in the Korean strains CMC2 and CMC3. Population-specific PCR amplification with Japanese A. catenella type-specific PCR primers designed from the type J sequence yielded PCR products for Japanese strains only, showing that the unknown gene can be used for a population analysis of Korean and Japanese A. catenella.

Population and genetic status of a critically endangered species in Korea: Hydrangea luteovenosa (Hydrangeaceae)

  • Choi, Hyeok-Jae;Ito, Takuya;Yokogawa, Masashi;Kaneko, Shingo;Suyama, Yoshihisa;Isagi, Yuji
    • Korean Journal of Plant Taxonomy
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    • v.47 no.1
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    • pp.1-5
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    • 2017
  • The population status of Hydrangea luteovenosa Koidz. in Korea was investigated, with an emphasis on its genetic diversity. From field surveys, we obtained the only locality record for a wild population in Jeju Island, which contained 285 individuals in total. Genotyping was performed using five microsatellite markers for the all extant plants in Korea. Three Japanese populations were also genotyped for the comparative analyses. The genotyping result showed that the Jeju population consisted of only two multilocus genotypes, including identical heterozygous genotypes at two loci; it had been maintained mostly by vegetative reproduction; and although the Jeju population is geographically far from Japanese populations, all alleles observed in the Korean population were shared with Japanese populations, suggesting the possibility that H. luteovenosa in the Jeju Island had been recently migrated or introduced from Japan. Future ecological and genetic studies associated with negative effects of low genetic variation will be essential for determining the conservation direction of the threatened Korean population of this species.

Intraspecific Molecular Phylogeny, Genetic Variation and Phylogeography of Reticulitermes speratus (Isoptera:Rhinotermitidae)

  • Park, Yung Chul;Kitade, Osamu;Schwarz, Michael;Kim, Joo Pil;Kim, Won
    • Molecules and Cells
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    • v.21 no.1
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    • pp.89-103
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    • 2006
  • Population structure was investigated in Reticulitermes speratus populations in the Korean Peninsula and the Japanese Archipelago. All trees derived from analyses of the combined sequence dataset of two mitochondrial genes, COII and COIII, showed that R. speratus populations cluster into two major clades comprising the Korean/southern Japanese populations and the northern Japanese populations. Analysis of population genetic structure showed strong genetic partitioning between populations of the two clades. To understand historical migration routes and current distributions, the phylogeographic history of R. speratus was inferred from intra-/interspecific phylogeny and divergence times estimated between the clades of the phylogenetic tree. The estimated migration route and divergence time of ancestral R. speratus are congruent with recent paleogeographic hypotheses involving land-bridge connections between the Asian continent and the Japanese Archipelago. We suggest that ancestral R. speratus separated into northern and southern Japanese populations after its migration into the Japanese main islands from East China during the early Pleistocene via the East China Sea basin, which may have been exposed during that period. The Korean populations seem to have diverged recently from southern Japanese populations; this may explain the current distribution of R. speratus in the Japanese Arachipelago, and account for why it is restricted to northern areas of the Tokara Strait.

Effect of Proportion of Recorded Cows Inseminated by Young A. I. Bulls on Genetic Improvement in Japanese Holstein Population

  • Terawaki, Y.;Shimizu, H.;Fukui, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.4
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    • pp.410-415
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    • 1998
  • The effects of the proprotion of cows inseminated by young A. I. bulls on genetic improvement in the Japanese Holstein population were examined using a simulation technique. The proportion of recorded cows inseminated by young A. I. bulls was assumed to be from 10% to 100% of the total number of recorded cows. The expected total genetic improvement was estimated for all cows and recorded and non recorded cows. The effects of the above were remarkable in the schemes that proven sires were used to produce recorded and non recorded cows for a limited time. Also the increase in the rates for -the expected total genetic improvement was larger when the proportion of recorded cows that were inseminated by young A. I. bulls was about 10% to 40%. When the expected total genetic improvement was estimated for the entire population, we found that the highest values were in a range of about 40 to 60% recorded cows that were inseminated by young A. I. bulls. On the other hand, the expected total genetic improvement that was only estimated in recorded cows dramatically decreased for more than 40% of the recorded cows. The results of this study showed that the optimal proportion of recorded cows inseminated with young A. I. bulls should be about 30% in the Japanese Holstein population.

A comparative Study of Changing Pattern of Cause of Death Analysis of Korean, Korean in Japan and Japanese (재일한국인의 생활문화의 이질화와 적응과정에 관한 보건학적 연구(제 1보 한국, 재일한국인, 일본의 사인구조분석)

  • 김정근;장창곡;임달오;김무채;이주열
    • Korea journal of population studies
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    • v.15 no.2
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    • pp.15-59
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    • 1992
  • After world war II Japanese life expectancy has been improved remarkably, and reached the highest level in the world around late 1970's. The life expectancy of Korean has also shown tremendous improvement in recent years with about 20 year's gap from the Japanese. The reason of rapid improvement of life expectancy can be explained by changes in the structure of cause of death due to health system, living standard, social welfare, health behavior of individuals and so on. Korean in Japan is placed under different situations from both Korean in Korea and Japanese in these regards, and expected to show different picture of cause of death pattern. The objective of this study is the comparision of changing patterns of cause of death of three population groups, Korean in Japan, Korean in Korea and Japanese, and to investigate the reasons which effect to the structural difference of mortality cause with special emphasis on health ecological aspects. One of the major limitations of the Korean causes of death statistics is the under-registration which ranges about 10% of the total events, and inaccuracy of the exact cause of death. Some 20% of registered deaths were unable to classify by ICD. However, it is concluded that the Korean data are evaluated as sufficient to stand for over-viewing of trends of cause of death pattern. The evaluation is done by comparing data from registration and field survey over the same population sample. Population data of Korean in Japan differ between two sources of data; census and foreigner's registration. Correction is done by life table method under the assumption that age-specific mortality pattern would accord with that of the Japanese. The crude death rate was lowest among Korean in Japan, 5.7 deaths per 1,000 population in 1965. The crude death rates of Korean in Japan and Japanese are increasing recently influenced by age structure while Korean in Korea still shows decreasing tendency. The adjusted death rate is lowest among Japanese, followed by Korean in Japan, and Korean in Korea. The leading causes of death of Korean in Korea until 1960's was infectious diseases including pneumonia and tuberculosis. The causes of death structure changed gradually to accidents, neoplasm, hypertensive disease, cerebro-vascular disease in order. The main difference in cause of death between Korean and Japanese if high rate of liver diseases and diabetes for both Korean in Japan and Korea. A special feature of cause of death among Korean in Korea is remakably high rate of hypertensive disease, which is assumed to be caused by physicians tendency in choosing diagnostic categories. The low ischemic heart disease and high vasculo-cerebral disease are the distinctive characteristic of the three population groups compared to western countries. Specific causes of death were selected for detailed sex, age and ethnic group comparisons based on their high death rates. Cancer is the cause of death which showed most dramatical increase in all three population groups. In Korea 20.1% of all death were caused by cancer in 1990 compared with 10.5% in 1981. Cancer of the liver is the leading cause of cancer death among Korean in Japan for both sexes, followed by cancer of the lung and cancer of the stomach, while that of Korean in Korea is cancer of the stomach, followed by cancer of the liver and cancer of the lung for male. Causes of infant mortality were examined among the three population groups since 1980 on yearly bases. For both Japanese and Korean in Japan, leading cause of death ranks as conditions originating in the perinatal period, congenital anomalies, accidents and other violent causes. Trends since 1980 for these two population groups in the leading cause of infant mortality showed no changes. On the contrary, significant changes in leading cause of death structure in Korea were observed : the ranking of leading cause of death in 1981 were congenital asnomalies, pneumonia bronchitis, infectious disease, heart disease, conditions originating in the perinatal period, accident and other violent causes ; in 1990 the ranking shifted to congenital anomalies, accident, pneumonia bronchities, conditions originating in the perinatal period, infectious disease. The mortality rate by congenital anomalies in Korea continuously grew than any other causes. Larger increase ocurred during the 1990's

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Education as a Soft Power Resource to Promotion of Immigration and Assimilation in Japan

  • Rothman, Steven B.
    • Analyses & Alternatives
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    • v.2 no.2
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    • pp.1-30
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    • 2018
  • The concept of soft power presents both theoretical and practical difficulties for researchers and policy makers. This essay examines the practical use of soft power and argues that soft power resources in education are important for attracting individuals to migrate between countries and assimilate to the new language and culture of the new location. Japan's attempts to utilize soft power resources in its educational system have provided mixed results dependent on the target population. Japan has successfully attracted individuals into fields related to higher education much more so than skilled labor programs. This essay discusses the importance of educational soft power resources in Japanese strategy to increase educated working population that is assimilated to Japanese language and culture. After reviewing the literature on soft power in Asia, and Japanese cultural integration policies, the essay examines three cases of Japanese educational soft power - the JET Programme, the caregiver-training program, and internationalization of university programs. In addition, the essay shows that Japan is more successful attracting higher educated individuals seeking higher paying employment rather than skilled labor through these programs.

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Southeast Asia in Japan's Spiritual Market: The Sacralization of Exoticism

  • Gaitanidis, Ioannis
    • SUVANNABHUMI
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    • v.8 no.1
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    • pp.95-119
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    • 2016
  • From the migrant care-workers arriving in Japan from the Philippines and Indonesia to support the depleted social support system for the large population of the elderly (Ogawa 2012) to the increasing number of retiring Japanese embarking on long-stay tourism in Malaysia (Ono 2015), the Japanese image of Southeast Asia as an exotic destination offering cheap labor in return for official development assistance seems to be fading away. Yet these changes are not necessarily reflected in the way contemporary Japanese, especially those who belong to the global, "spiritual-but not-religious" (Fuller 2001) population, think of and "consume" Southeast Asia in their daily lives. Using three case-studies, spiritual tours, Thai massage, and an NGO founded by a Japanese spiritual therapist, this paper argues that in Japan's large spiritual market, which targets people seeking alternative ways to express their religiosity, the old-fashioned colonial exoticism of Southeast Asian narratives were integrated in a totalizing discourse, in which Japan remains the exceptional outlier (Tanaka 1993), a country still claimed to be "advanced" both spiritually and economically.

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Population analysis of the toxic dinoflagellate genus Alexandrium by novel molecular markers

  • Kim, Choong-jae;Kim, Sook-Yang;Kim, Kui-Young;Kang, Young-Sil;Kim, Hak-Gyoon;Kim, Chang-Hoon
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.134-135
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    • 2003
  • The geographic expansion of the toxic dinoflagellates genus Alexandrium has been shown to be world wide ranging. The members of the genus Alexandrium ocnstituted of 20-30 species did not show substantial differences in their morphology, which is mostly referred in the 'tamarensis species complex', except some species. Though rDNA sequences variations are very few and pseudogene types are so diverse that it is difficult to use them as the specific markers. In this study, we outlined Korean and Japanese A, tamarense and A. catenella regional isolates by phylogenetic analysis inferred from no cutting alignments of LSU rDNA D1-D2 and SSU rDNA sequences to group these regional isolates. The results were compared to RFLP patterns of PCR products targeted chloroplast DNA. Lastly screening of highly repeated microsatellite DNA which is frequently used for population analysis in eukaryotes was conducted. A. catenella regional strains identified by the sequencing of rDNA D1-D2 domain were divided into at least 3 groups of type E, CMC and Chinese type, divergence root may not be deep comparing with that of A. tamarense whose pseudogenes are very variable. Results of RFLP pattern and the phylogeny of the unknown gene targeting chloroplast showed that Korean and Japanese A. catenella regional isolates were divided into 3 types: Korean, Japanese and the third CMC types. Population-specific PCR amplification with Japanese A. catenella type-specific PCR primers was useful method for population analysis of A. catenella. Various types of satellite sequences such as 5 nucleotides repeats were obtained from A. tamarense and A. catenella. The 5 nucleotides repeats were primed at the both 3'and 5' ends, and these repeats were prominent as longer repeated motifs. This repeated DNA was intercalated as internal sequences containing various types subrepeats. It is expected that these satellite DNA would be a useful molecular population marker through detail comparison among Alexandrium regional isolates to trace their transferring pathway and to prevent their human-associated their regional extents.

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The Study of Japanese Food Distribution System in response to Diversification of Food Concept (식품컨셉의 다양화에 따른 일본 식품유통시스템의 변혁에 관한 연구)

  • Oh, Bum-suk;Kim, Sang-cheol
    • Journal of Distribution Science
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    • v.3 no.2
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    • pp.15-28
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    • 2005
  • This study assessed the development of Japanese food distribution system in response to changes in the needs of consumer population the current food concepts can be divided into "processed" and "perishable" foods we expended the current concept introducing "processed perishable foods" and "perishable processed foods", and how this modified term contributed to more effective food distribution system in Japan. We further assessed the effects of changes in the needs and perception in Japanese consumer population on food distribution system, which included PB goods development as well as diversification of chain system. Our study in the development of Japanese consumer population and food distribution system can be compared to that of Korea, providing a direction for systematic and effective food distribution system.

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Distribution Pattern of cpSSR Variants in Korean Populations of Japanese Red Pine (국내 소나무 집단에 있어서 cpSSR 표지자 변이체의 분포양상)

  • Hong, Yong-Pyo;Kwon, Hae-Yun;Kim, Yong-Yul
    • Journal of Korean Society of Forest Science
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    • v.95 no.4
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    • pp.435-442
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    • 2006
  • A total of 167 peculiar haplotypes confirmed from 28 cpSR variants that were observed in 19 populations of Japanese red pine in Korea through cpSSR marker analysis. Thirteen individuals that showed identical haplotype dispersed evenly in 10 populations, and the average number of effective haplotype within population was 13.37. Estimate of genetic diversity (He) was 0.987 on the basis of cpSSR haplotype variants that was equivalent to or higher than the estimates reported in other studies on some forest tree species. Estimation of genetic diversity (S.I.) on the basis of cpSSR variants composing each haplotype revealed the highest estimate of 1.109 for the population of Gangwon-Yeongwol and the lowest estimate of 0.411 for the population of Gyeongbuk Mungyeong with the average of 0.887. Most of observed cpSSR variants appeared to exist commonly in 19 populations (97.62%), and genetic differentiation of cpSSR variants among populations was turned out to be weak (${\Phi}_{ST}=0.024$). Relatively fast rate of mutation of cpSSR marker might be a major cause for such weak population differentiation. There was no identical haplotype shared between 39 population pairs of 173 pair-wise population pairs. Estimation of genetic distance among 19 populations on the basis of population pairs was also impossible, that might be resulted from restricted migration among 19 populations. Considering the observed distribution patterns of cpSSR variants in addition to the previous studies on I-SSR variants, informations on the present geographic location and genetic status of populations should be considered together for effective sustainable management of the genetic resources of Japanese red pine in Korea.