• Title/Summary/Keyword: population migration

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DNA Analysis of mtDNA COI Gene in the Sharp-toothed Eel (Muraenesox cinereus Forskal) from Yeosu, Jinhae, Jeju, Goseoung, Jangheung and Haenam Populations in Korea Using PCR-aided RFLP

  • Oh, Taeg-Yun;Jeong, Sun-Beom;Cho, Eun-Seob
    • 한국환경과학회지
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    • 제20권4호
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    • pp.551-554
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    • 2011
  • The production of the sharp-toothed eel by commercial catch off waters of Korea is annually declined after 1978. This study was carried out to obtain the stock management of the sharp-toothed eel using the PCR-aided RFLP method. The mtDNA COI gene was amplified using species-specific primers and PCR product was observed to 700 bp. Amplified DNA fragments were treated with six kinds of restriction enzymes (BaeHI, EcoRI, PstI, Ksp22, HinfI and HaeIII). The treatment of HaeIII showed a distinct PCR product between Yeosu/Jinhae/Jeju/Goseoung and Jangheung/Haenam populations that were observed from 300 to 400 bp in reference to 100 bp molecular marker. However, DNA fragment within populations had an identical pattern. The phylogenetic homology is 82% between two populations inferred from RFLP PCR product pattern using NTsysPC ver. 2.1. The use of HaeIII plays an important role in discriminating populations. It is thought that adults after over-wintering in the southern part of Jeju migrate to the Yeosu, Jinhae and Goseoung regions to spawn instead of to southwestern waters. Individuals within populations showed a relatively active genetic mixing and migration regardless of geography. However, the genetic ancestor of Jangheung and Haenam populations is appeared to be more adjacent to China or Japan than Jeju.

도시 근교 농촌마을 경제활동의 다양성에 관한 연구: 경기도 양평군 서종면의 사례 (A Study on the Divergence of Economic Activities between Rural Villages in Rural-Urban Ares : The Cases of Two Villages of Seojong-Myeon in Yangpyeong County)

  • 고경호;김태연
    • 한국유기농업학회지
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    • 제27권3호
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    • pp.289-306
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    • 2019
  • The study is a comparative analysis of the differences in economic activities of two rural villages near the city. It is the general notion that rural villages near large cities lose the characteristics of traditional rural villages and change the areas with urban characteristics due to the influence of urbanization. The survey also showed that Munho 4-ri and Jeongbae 1-ri in Gyeonggi-do have urban characteristics, such as population growth, agricultural activity reduction and non-agricultural activity increase, and community activity reduction. However, they also found that there were important differences in the future development patterns of the two villages. In other words, the reasons and purposes of migration of people moving to the two villages, the differences in the system of economic activity in the villages, and the differences in community cooperation are emerging. Therefore, the study shows that policies to develop rural villages near cities need to be implemented differently based on the characteristics of those villages.

남강 습지에 분포하는 키버들 집단의 공간적 상관 분석 (Spatial Autocorrelation Analysis among Subpopulations of Salix koriyanagi in Swampy Area at the Namgang River, Korea)

  • 허만규
    • 생명과학회지
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    • 제18권11호
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    • pp.1465-1470
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    • 2008
  • 키버들(Salix koriyanagi)은 관목으로 한국에 고유종이다. 전분 젤 전기영동을 사용하여 남강 상류 저습지에 분포하는 키버들 집단에서 유전적 다양성과 집단구조를 분석하기 위해 집단을 세분하였다. Moran's I값으로 세분화된 1.0 m 간격별 구간 내 개체들의 대립유전자좌위에서 유의한 상관을 조사한 결과 약 6 m 간격 내 개체들의 뭉침이 나타났으며, 12 m 이상일 경우 유의한 차이가 나타났다. 따라서 키버들의 경우 집단구조가 12 m 이내에서 형성됨을 알 수 있었다. 대부분의 집단이 제한된 유전자 유동과 유효집단의 감소가 예상되며, 겨울철 가뭄과 여름철 홍수로 심한 병목을 유발하고, 주기적인 홍수와 배수로 인한 개체수의 교란이 발생한 것으로 판단된다.

장수명주택 해외진출을 위한 대상국가의 외부환경분석 (External Environment Analysis of Target Countries for Overseas Expansion of Long-life Housing)

  • 정준수;이보라
    • 한국주거학회논문집
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    • 제26권5호
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    • pp.71-78
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    • 2015
  • Currently, the Korean construction industry is shifting its interest to the overseas construction market because of a stagnating domestic market. In the meantime, the international housing construction market is expanding with respect to new city development projects that are supported by population growth and urban migration. Despite the Korean construction industry's expertise in new city development, technology, and systems for apartment supply, the share of Korean players in the international housing construction market is continuously decreasing. As a measure to overcome this situation, the authors of this study considered the paper "The Development of a Cost Effective, Long-life Housing Model and Construction of Testbed," which is currently in progress as a part of national project. Through literature review and interviews with experts, the authors determined that there are "column+minimum interior (infill)" apartments that are similar to the long-life housing in some areas of China, Southeast Asia, and Russia. Candidate countries expected to be feasible for the entry of long-life housing were selected by determining the top countries that have already entered the long-life housing market and analyzing those selections through additional specific techniques. The external environments of the selected countries were also analyzed. Please refer to the full paper for details.

사회변동에 따른 한국고유의 발효식품의 관리의 변화에 관한 연구 - 1960년대 이후의 문헌조사를 중심으로- (A Study on the Influence of Social Changes on the Management of Indigenous Fermented Foods in Korean Families)

  • 한경선;윤서석
    • 한국식품조리과학회지
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    • 제7권1호
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    • pp.1-9
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    • 1991
  • The purpose of this study is to investigate the management of Indigenous fermented foods during the period of economic development starting from 1960 until now, and to specify their correlation, while paying special concern to the variables of social change such as the increase of people's income, ceaseless migration of population, change in the family structure, heightening up of the educational level of women and the resulting increase of chances for getting employment, all of which may affect the management of Indigenous fermerted foods in korean families. The result is as follows. Basic seasonings and dishes such as soy bean sauce, red pepper paste, pickled seafoods, and Kimchi, are inclined to be bought as readymade products or provided by relatives in case of many nuclear families rather than made at home, which is a traditional way of home life. However, Kimchi and basic sauces or redpepper paste still show high rate of being made at home. Social variables which affect such tendency are the number of family members, the age and educational level of housewife, and the type of residence.

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조선(朝鮮)의 왕실(王室) 차처방(茶處方)(다음(茶飮))의 운용(運用) - 승정원일기(承政院日記)의 내용을 중심으로 - (A Study on the Use of the Medicinal Tea in Chosun Dynasty)

  • 김종오;오준호;김남일
    • 한국한의학연구원논문집
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    • 제15권3호
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    • pp.11-17
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    • 2009
  • This paper treats with transitional development of medico-hygienical situation in district Yanbian along with the evolution in specific field of medicine. This work is particularly important in shaping TKM identity as TCM embraces Chao medicine asserting it as one included in TCM. This research deals with themes of migration of Chao minorities to this territory and their medico-hygienical situation. Lifted bans on immigration in late Qing dynasty with uncertainty of Korea(Chosun) triggered the immigration to this district. The flow was heavily strengthened under the influence of Westerners and Japanese imperialism into china which consequently provoked the ruin of Qing dynasty, the civil war between republicans and communist and the socio-political changes in Korea. As population growths, the establishment of hospitals and immigration of healthcare professionals were also increased. Though this district is located in Chinese mainland the influence of Japanese was also relevant which lead to medical practice reflecting both sides. Mutual combination and influence of western(contemporary) medicine, TCM and TKM practices made the particularity of Chao medicine.

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최저주거기준으로 측정한 농촌지역 고령자의 주거수준 변화와 지역간 격차, 1995~2005 (The Change and Regional Disparity of Elderly Housing Conditions in Rural Areas, 1995~2005)

  • 김현중;강동우;이성우
    • 농촌계획
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    • 제16권1호
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    • pp.49-62
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    • 2010
  • As people get aged, we need to pay more attention to the elderly living condition with respect to welfare policy. The present study focuses on housing condition of elderly people living in rural area, and analyzes its determinants, periodical difference, and regional disparities, incorporating an index of minimum housing standard. This study applies multi-level logit model that has a strong statistical advantage that can take random aspects of household and regional context into account. We found that married couple household, presence of economically-active family members, higher education, specialized profession, migration and higher level of land price tend to lower the probability of residing in substandard housings. We also found that housing conditions for elderly people prove to be different by regions and it is particularly noticeable in mountainous rural areas in Gyeongsangnam-do and Gyeongsangbuk-do with the poorest elderly housing conditions. Results also implies that housing welfare policies should be implemented differently considering the target groups based on regional differences. We conclude with some additional policy implications for the elderly living in rural areas.

노령화사회에 대비한 농촌지역 장수도의 정의 및 장수지역 기준마련에 관한 연구 (A Study on the Longevity Index and the Criteria of Longevity in Rural Area for Aged Society)

  • 정남수;이정재;김한중;이지민;서교;이호재
    • 농촌계획
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    • 제9권3호
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    • pp.35-39
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    • 2003
  • In this study, the longevity index was suggested for researches about social and environmental effects to human immorality and criteria for defining longevity area were developed using statistical analysis. Candidates indexes based on researches about the tend of human death ratio were investigated. As a result statistical analysis, ratio of population over 85 yearn old and over 65 years was selected as a longevity index. Statistical analysis on the longevity distribution at each district showed that 'eup' and 'myun' are appropriate spatial unit to study social and geographical characteristics of longevity. The spatial analysis using the $ArcView^{TM}$ with the suggested index shows the time dependent variances of degree of immorality and spatial relationship between degree of immorality and human migration.

In Vivo Expression of EphrinA5-Fc in Mice Results in Cephalic Neural Crest Agenesis and Craniofacial Abnormalities

  • Noh, Hyuna;Park, Eunjeong;Park, Soochul
    • Molecules and Cells
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    • 제37권1호
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    • pp.59-65
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    • 2014
  • Eph receptors and their ligands ephrins have been implicated in guiding the directed migration of neural crest cells (NCCs). In this study, we found that Wnt1-Cre-mediated expression of ephrinA5-Fc along the dorsal midline of the dien- and mesencephalon resulted in severe craniofacial malformation of mouse embryo. Interestingly, expression of cephalic NCC markers decreased significantly in the frontonasal process and branchial arches 1 and 2, which are target areas for the migratory cephalic NCCs originating in the dien- and mesencephalon. In addition, these craniofacial tissues were much smaller in mutant embryos expressing ephrinA5-Fc. Importantly, EphA7-positive cephalic NCCs were absent along the dorsal dien- and mesencephalon of mutant embryos expressing ephrinA5-Fc, suggesting that the generation of cephalic NCCs is disrupted due to ephrinA5-Fc expression. NCC explant experiments suggested that ephrinA5-Fc perturbed survival of cephalic NCC precursors in the dorsal midline tissue rather than affecting their migratory capacity, which was consistent with our previous report that expression of ephrinA5-Fc in the dorsal midline is responsible for severe neuroepithelial cell apoptotic death. Taken together, our findings strongly suggest that expression of ephrinA5-Fc decreases a population of cephalic NCC precursors in the dorsal midline of the dien- and mesencephalon, thereby disrupting craniofacial development in the mouse embryos.

Regenwurmpopulationen in ackerbaulich ge-nutzten Flachen und deren Randbereichen. I.Ostliches Harzvorland

  • christine Hemmann;Leithold, und-Gunter
    • 한국유기농업학회지
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    • 제3권1호
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    • pp.23-42
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    • 1994
  • This paper studied earthworm populations in fields under practical cultivation in the Eastern Harzforeland (Germany). The examined sites differed insignificantly in their climatic and soil conditions. The examination was a comparison between a field and a narrow edge or meadow. A combination of Oktett method and handsortin was used. The five different habitates seven earthworm species were discoverd. The most frequently foundd were A. rosea, A. caliginosa, and A. chlorotica. There were clear differences in species between the habitates of each site. Generally the edge or the meadow contained one (Zoeberitz) or two (Zscherben) more species than the field. The composition of species differed between 1990 and 1992. In the dry Autumn of 1991 there were less species found at both sites. The occurance of earthworm species depends on the weather. Moisture influencing similiarity of abundance and bio-mass were recorded in three out of four habitates. Starting on a high level in Autumn 1990 the abundance as well as biomass decreased until Autumn 1991 and increased the following year. The number from 1990 were never reached again during the examination. One year of normal precipita-tion was not enough to return the population to the beginning level. Great differences in the number of earthworms between the compared habitats suggest that the edges and meadows are a potential immigration source into a field which is poor on earthworms. Structrues of distribution near the edge refer to a migration from a high populated edge into an almost empty field.

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