• Title/Summary/Keyword: Migration distance

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Spatio-temparal Pattern Formation of Abdominal Muscle in Xenopus Iaevis

  • Ko, Che-Myong;Chung, Hae-Moon
    • Animal cells and systems
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    • v.1 no.2
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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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A Demand Analysis on Urbanites' Retired Life in the Countryside (도시민의 은퇴 후 농촌정주에 대한 수요분석)

  • Yoon, Soon-Duck;Park, Gong-Ju
    • Journal of Korean Society of Rural Planning
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    • v.12 no.2 s.31
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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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    • v.24 no.3
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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.

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

  • 이상일
    • Water for future
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    • v.25 no.4
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    • pp.61-73
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    • 1992
  • There are needs to examine the consequences of a regulation in effect to control the migration of leachates from disposal sites. The main objective of this study is to illustrate the methodology to evaluate basic disposal designs for compliance with a certain regulation, The "100/100 rule" is selected for demonstration purpose which dictates that the time for the leachates to travel a horizontal distance of 100feet (30.5m) away from the property where the landfill or pond is located must exceed 100 years. The two primary methods for disposal of ash from coal-fired utility plants, landfill and pond, are studied, Numerical groundwater flow analysis resulted in pressure head distribution and flux information in the cross-section of the domain while path line analysis provided travel path and time of leachate migration to compliance zone.ance zone.

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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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    • v.32 no.1
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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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A Trial Using a Micro Chip for Horse Identification (경주마에 있어서 개체감별을 위한 Micro Chip의 이용에 대하여)

  • Lim Young-Jae;Lee Soo-Deuk;Lee Shi-Young;Bak Ung-Bok
    • Journal of Veterinary Clinics
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    • v.9 no.1
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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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The Effects of Regional Characteristic Differences on the Migration (지역 간 특성차이가 서울시 청년층 이동에 미치는 영향 분석)

  • Kim, Leeyoung
    • Journal of the Korean Regional Science Association
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    • v.35 no.2
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    • pp.49-57
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    • 2019
  • The young generation in life cycle that social position is rapidly changing is play an important role in a regional development because they can increase social and natural population in the region. This study analyzed the relationship between the movement of young generation and the regional characteristics including housing market characteristics in Seoul. As the results, the movement of young generation was influenced by commuting distance and location of jobs as the gravity model has suggested. In addition, housing supply and housing price (or Jeonse price) is an important factor for the movement of young generation. It can be inferred that the more price gap such as Jeonse price and housing supply gap are increased, the more out-migration of young generation in Seoul is increased. However, the housing demand of young generation in employment centers will be increased because jobs contribute to increasing the inflow of young people. Therefore, the policies of central and Seoul government that supply housing in job rich and high accessibility areas are needed for young generation. In addition, if public housing and affordable housing are supplied in the other areas, it can contribute to reduce the out-migration of young people in Seoul.

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

  • 이희봉
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.2
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    • pp.146-150
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    • 1990
  • This study was conducted to investigate the genetic analysis of esterase isozymes in maize with tillers. The materials used for the study were stele tissue for five day old seedlings of IK inbred line with tiller and A-type inbred line with no tiller, their Fl and F,. The methods employed for the study were same as previous report by Lee and Choe. A total of thirteen isoesterase enzyme bands were identified and five zones were distinguised according to both migration distance and genetic segregation patterns. The E$\sub$0.3/, E$\sub$0.4/ and E$\sub$0.5/ loci appeared from orgin to 0.5cm migration distance were controlled by the two alleles in (IK/A-type)F$_2$ and the E$\sub$0.3/+E$\sub$0.4/ of variants was controlled by codominant alleles. The E$\sub$1.0/, E$\sub$1.2/, E$\sub$1.5/ and E$\sub$1.8/ loci appeared from 1.0cm to 1.8cm were also controlled by the two alleles. However, the null band was functioned alleles. The E$\sub$2.8/, E$\sub$3.0/ and E$\sub$3.5/ loci appeared from 2.8cm to 3.5cm migration distance were very active and near location. A total of individuals with two paried bands of these loci were more than those of three paired bands(x$^2$=0.327$\^$**/). The activity of bands appeared over 3.8cm were very low and these were controlled by the two alleles. In above results, genetic segregations of stele tissue of maize with tillers were suggested to be controlled by Mendelian genetic laws.

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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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    • v.19 no.3
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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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    • 2002.10a
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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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