• 제목/요약/키워드: Migration distance

검색결과 121건 처리시간 0.031초

Spatio-temparal Pattern Formation of Abdominal Muscle in Xenopus Iaevis

  • Ko, Che-Myong;Chung, Hae-Moon
    • Animal cells and systems
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    • 제1권2호
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    • pp.329-335
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    • 1997
  • The final pattern of the skeletal muscle of a vertebrate depends on the position-specific behavior of the muscle precursor cells during early developmental process and the abdominal muscle is made of cells which migrate a relatively long distance from their original tissue, myotome of dorsal mesoderm. We report the spatia-temporal migration pattern of abdominal muscle in Xenopus laevis by in situ hybridization and immunohistological studies. Shortly after hatching tadpole stage (stage 31/32), a group of myotomal cells detaches from the lower tip of the second somite and migrates ventrally to the lower position of abdomen. At stage 34/35, a second cell group migrates away from the third somite. Total 7 myotomal cell groups migrate ventrally one by one from the second to eighth myotome along their own pathways through the cell free space located between epidermis and subepidermal layer of the abdomen. During migration, the sizes of the cell groups (abdominal muscle anlagens) are increased to several tens fold. Around stage 40 all the abdominal muscle anlagens reaches their final positions and are interconnected side by side rostrocaudally. They are also connected to other types of muscles, forming a large multisegmented abdominal muscle. Heat shock study suggests that the disruption of segmentation of somites does not block the detachment of abdominal muscle anlagen, though the treatment gave stage- and dosagedependent effects on the migration speed.

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도시민의 은퇴 후 농촌정주에 대한 수요분석 (A Demand Analysis on Urbanites' Retired Life in the Countryside)

  • 윤순덕;박공주
    • 농촌계획
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    • 제12권2호
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    • pp.37-47
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    • 2006
  • Recently, due to the growing concern of the public in rural amenities and hobby farming works, much more urbanites, especially near-retirees, have been interested in rural life style than before. However, in spite of popular preference to ruralities, little has been known about their demand on retired rural life. Therefore, this study examined urbanites' attitude to preparatory works for out-migration, preferred residential site conditions and life style in the countryside. For this purpose, data were collected from a survey with the sample of 386 urban residents aged 40 to 65 rho hoped moving into the countryside after retirement, through structured questionnaires. Descriptive statistical works were performed using SPSS/PC windows program. The major findings of this study were as follows; (1) Host of urbanites, who answered in this study, planned to prepare ex-urban movement in their fifties and to put into practice in their sixties. (2) Key factors of location decision on movement were proximity/accessibility to centre city, medical service level, and distance to their family or friends. And about a half of respondents wanted second home in the countryside. (3) Most favoured rural life styles were nature-friendly well-being and hobby/healthy firming. Generally, the respondents of this survey had the positive attitude to do works in their later life, especially preferred to farming and volunteering in their communities.

Reflection Seismology in the Southern Ayu Trough, a Slow-spreading Divergent Boundary

  • Hong, Jong-Kuk;Lee, Sang-Mook
    • Ocean and Polar Research
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    • 제24권3호
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    • pp.189-196
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    • 2002
  • A multichannel seismic survey was conducted in the southern Ayu Trough which is the only spreading boundary between the Philippine Sea and Caroline plates. The seismic system used in this study comprises of 2.46-l sleeve gun and a 12-channel streamer with a group interval of 6.25m. Migration technique was used to analyze seismic velocity, and poststack depth migration was applied to the stacked data. The sediment thickness obtained from the depth section tends to increase with distance from the spreading axis. Sedimentation rates are poorly constrainted in the study area. The apparent half-spreading rates estimated from the sediment thickness and sedimentation rate from DSDP hole on the caroline plate are 4.7mm/yr and 7.9mm/yr at $1^{\circ}24'N\;and\;0^{\circ}42'N$, respectively, which are fester than Previously suggested. On the basis of new oblique spreading geometry, the recalculated spreading rates are 5.4mm/yr and 9.1mm/yr at $1^{\circ}24'N\;and\;0^{\circ}42'N$, respectively. Seismic sections show that the topography is asymmetric across the Ayu Trough and the acoustic basement is rough. These features are consistent with the earlier suggestion that the Ayu Trough is a slow-spreading divergent boundary. A detailed examination of seismic profiles away from the axis shows that sediments can be divided into two layers which implies a possible change in the spreading rate anuor sedimentation condition during the formation of the trough.

침출수 이동 해석을 통한 석탄재 처분방식의 평가 (Evaluation of Fly Ash Disposal Methods by Analysis of Leachate Migration)

  • 이상일
    • 물과 미래
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    • 제25권4호
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    • pp.61-73
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    • 1992
  • 폐기물 처분장으로부터 인간생활 환경으로까지 침출수가 어떤 방향과 속도로 유출될 것인가하는 것은 많은 사람의 관심의 대상이며, 어떤 처분장 설계가 관련 규제법을 효과적으로 만족시키고 있는가를 알아야 할 필요가 있다. 침출수이동에 관한 해석방법을 제심함에 있어, 화력발전의 결과로 생기는 석탄재의 폐기 방식중 두 가지 대표적인 방식인 매립방식과 연못방식에 대한 평가를 예시하였다. 관련 규제법으로는 "100/100 룰", 즉, 처분장으로부터 100ft(30.5cm) 떨어진 곳까지 침출수가 도달하는데 100년이상 걸려야 한다는 제약조건을 적용하였다. 수치해석에 의한 지하수 유동방정식의 해는 압력수두 분포와 유동량(flux)에 관한 정보를 제시하여 주었으며, 유적선(pathline)의 해석은 침출수 이동 경로와 시간에 관한 예측을 가능케 하였다.을 가능케 하였다.

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Patterns of Vertical Distribution and Diel Vertical Migration of Zooplankton in the East Sea of Korea (Sea of Japan)

  • Park, Chul;Lee, Chang-Rae;Hong, Sung-Yun
    • Journal of the korean society of oceanography
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    • 제32권1호
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    • pp.38-45
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    • 1997
  • To find out the changes in vertical distribution patterns over the 24-h period, a key and the first step to tackle the problem of adaptive significance of diel vertical migration (DVM), vertically stratified time series samplings with multiple opening/closing plankton samplers were done in the East Sea of Korea (Sea of Japan). Sampling was done almost every 4 h for one day period following the same water parcel in Nov. 1995 and May 1996, respectively. Resultant patterns of vertical distribution showed that some species such as most abundant taxa Metridia pacifica and Scolecithyicella minor, both Copepoda, performed DVM even in the study area of strong thermal stratification. Their patterns of DVM such as distance scales and timing of movements were not the same each other, and they were separated from other taxa in the dendrogram obtained by the cluster analyses, Most minor taxa grouped in one, however, seemed not to do DVM in the study area of strong thermal stratification. They usually preferred the warmer surface layer where the foods were probably more abundant.

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경주마에 있어서 개체감별을 위한 Micro Chip의 이용에 대하여 (A Trial Using a Micro Chip for Horse Identification)

  • 임영재;이수득;이시영;박응복
    • 한국임상수의학회지
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    • 제9권1호
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    • pp.317-322
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    • 1992
  • This trial is concerned with practical application of a M. C. that was injected Into the horse's muscle in order to make a effective identification by computer compatible. Following results were obtained through the study of histopathologic changes, migration of M. C. and possible problems about practical application. 1. Muscle romboideus cervicalis(site 'A') was thought to be the best Injection site of M. C. in the horse. 2. There were no the exact interface between the M. C. and surrounding tissue. It seemed to be why the implanted transponder was located in the muscle fascia. 3. No evidence of migration in the tissues was found through the radiographs taken after implantation 4. There were no clinical disorder and interference with racing performance. 5. ID 100 from Trovan, Co. had some advantages comparing with TX 1400 L from Destron, Co. These are, for instance, the long readout distance and the easy application of computer in the field practive.

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지역 간 특성차이가 서울시 청년층 이동에 미치는 영향 분석 (The Effects of Regional Characteristic Differences on the Migration)

  • 김리영
    • 지역연구
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    • 제35권2호
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    • pp.49-57
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    • 2019
  • 생애주기단계에서 청년층은 그 사회적위치가 빠르게 변화하는 연령대로, 본 연구는 청년층의 인구이동에 주목하고 주택시장요인을 포함한 지역특성요인과 청년층 인구이동의 관계를 서울지역을 중심으로 실증 분석하였다. 분석결과, 청년층의 이동은 거리와 일자리는 중요한 이동의 원인이 되고 있다. 이외에 주택시장에서의 전세가격이나 주택공급이 청년층 이동에 유의한 영향 요인으로 작용하는 것으로 분석되었다. 또한 서울시내 개별 지역과 이동의 기원지간의 전세가격과 같은 가격의 차이가 커질수록, 주택공급 차이가 커질수록 서울시 청년층의 순전출이 지속될 수 있음을 유추할 수 있다. 분석 결과 일자리의 경우, 청년층 유입을 증가시키는 데 기여하고 있어 고용중심지 주변에서의 청년층 주거수요는 높아질 것으로 예상된다. 따라서 현재 서울시나 정부에서 추진하고 있는 일자리가 많은 지역주변이나 역세권 주변에서의 청년층을 대상으로 한 공공주택을 비롯한 민간의 주택공급이 원활하게 이루어질 필요가 있으며, 저렴한 가격으로 거주할 수 있는 공적 주택이나 민간임대 주택 공급이 지속된다면, 서울시 청년층 전출을 줄이는 데 기여할 수 있을 것으로 기대된다.

분벽성 옥수수에 대한 Esterase 동위효소의 유전분석 (Genetic Analysis of Esterase Isozymes in Tillering Maize)

  • 이희봉
    • 한국작물학회지
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    • 제35권2호
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    • pp.146-150
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    • 1990
  • 분벽성 옥수수에 대한 esterase 동위효소의 유전양상을 알아보고자 acrylamide gel 6.5%를 사용하여 분벽성인 IK 계통과 대조구로 무벽성인 A-type 계통을 교배하여 얻은 $F_1$$F_2$ 종자를 28$^{\circ}C$ 암조건하에서 발아시킨 유조직 중심주를 공시하여 전기영동한 결과는 다음과 같다. 1. 본 실험에 공시된 중심주조직은 음극효소를 포함하여 총 13개의 동위효소가 확인되었으며 이동거리에 따라 유전분이 양상이 5개군으로 구분되었다. 2. 원점으로부터 0.5cm에 존재하는 E$_{0.3}$, E$_{0.4}$, E$_{0.5}$ 동위효소는 2개의 대립인자에 의해 지배되었고, E$_{0.3}$+E$_{0.4}$ 변이체는 공우성 대립인자에 의해 지배되었다. 3. 밴드의 이동거리가 1.0cm에서 1.8cm에 존재하는 E$_{1.0}$ , E$_{1.2}$ , E$_{1.5}$ , E$_{1.8}$ 의 4개의 동위효소는 2개의 대립인자에 의해 지배되었고 존재하지 않는 비활성 밴드가 우성으로 작용하였다. 한편 변이체로 나타난 E$_{1.2}$ +E$_{1.5}$ 의 동위효소는 공우성 대립인자로 작용하였다. 4. 밴드의 이동거리가 2.8cm에서 3.5cm에 존재하는 E$_{2.8}$ , E$_{3.0}$ , E$_{3.5}$ 인 세 개의 밴드는 이들 중에서 두 개씩 나타나는 밴드가 세 개 모두 나타나는 개체수보다 현저히 많이 나타났다. ($\chi$$^2$=0.327$^{**}$ ). 5. 밴드의 이동거리가 3.8cm 이상에서 나타난 동위효소는 활성이 매우 낮았고 이들 효소는 모두가 두 개의 대립인자에 의해 지배되었다. 따라서 분벽성 옥수수 중심주 조직에 대한 esterase 동위효소는 멘델식 유전법칙에 의해 지배된다고 생각된다.각된다.각된다.

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A Novel Method to Measure Superior Migration of the Humeral Head: Step-off of the C-line

  • Park, Kyoung Jin;Eun, Hyeon Jun;Kim, Yong Min;Yoo, Jun Il;Lim, Chae Ouk
    • Clinics in Shoulder and Elbow
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    • 제19권3호
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    • pp.125-129
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    • 2016
  • Background: Superior migration of humeral head has been conventionally determined by measuring the acromiohumeral distance (AHD), We sought to devise a novel measurement system more reliably and accurately than AHD. We described a structural landmark called 'C-line'. In this study, we investigated the clinical usefulness of 'step-off of the C-line (SOC)' compared to that of AHD. Methods: The C-line formed from the medial margin of the proximal humeral head continuing up to the inferior margin of the articular glenoid and then to the lateral border of the scapula. The superior migration of the humeral head triggered by a rotator cuff tear introduces a discontinuity in this C-line. We measured the distance of this discontinuity. We enrolled 144 patients who underwent a rotator cuff repair. We selected 58 controls who didn't have any cuff lesions apparent on magnetic resonance imaging. Using radiographs derived from standardized true anteroposterior views of the shoulder, we measured the SOC and the AHD. We used t-tests for statistical analyses. Results: A rotator cuff tear was associated with an increase in SOC and a decrease in AHD. In control group, the mean SOC was $1.29{\pm}1.71mm$ and AHD was $9.71{\pm}2.65mm$. In cuff tear group, the mean SOC was $3.15{\pm}3.41mm$ and AHD was $8.28{\pm}1.76mm$. The mean SOCs of the patient group in relation to the mean SOC of the control group according to tear size, the SOCs of medium tear and lager groups showed statistically significant increase (p<0.05). Conclusions: The SOC may be a similarly effective to diagnose cuff tears of medium size and larger compared with AHD.

A Model to Estimate Population by Sex, Age and District Based on Fuzzy Theory

  • Pak. Pyong-Sik;Kim, Gwan
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.42.1-42
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    • 2002
  • A model to predict population by sex, age and district over a long-range period is proposed based on fuzzy theories. First, a fuzzy model is described. Second, a method to estimate the social increase by sex and age in each district is proposed based on a fuzzy clustering method for dealing with long-range socioeconomic changes in population migration. By the proposed methods, it became possible to predict the population by sex, age and district over a long-range period. Third, the structure and characteristics of the three models of employment model, time distance model, and land use model constructed to predict various socioeconomic indicators, which are require...

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