• 제목/요약/키워드: growth ages

검색결과 448건 처리시간 0.035초

성장기 아동의 상하악골 성장 및 제1대구치 위치적 변화에 대한 연구 (A STYDY ON GROWTH CHANGES OF MAXILLA AND MANDIBLE AND POSITION CHANGES OF FIRST PERMANENT MOLARS OF GROWING CHILDREN)

  • 조대희;손병화
    • 대한치과교정학회지
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    • 제17권2호
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    • pp.311-320
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    • 1987
  • The purpose of this study was to investigate the growth changes of maxilla and mandible and position changes of first permanent molars of growing children The author analyzed the data using cephalometric roentgenogram of 43 boys and 39 girls age of 6 to 11 with normal occlusion The obtained results were as follows 1 The eruption path of maxillary and mandibular first permanent molar superimposed on TM-ANS and mandibular plane shows individual variation 2 There was no correlation between horizontal and vertical changes of maxillary first permanent molar, but positive correlation in mandibular first permanent molar 3 As the eruption, the forward changes of mandibular first permanent molar was significantly greater than that of maxillary first permanent molar 4 As the ages were increased, there were irregular growth changes of maxilla and mandible 5 Growth changes of lower anterior facial height was relatively stable 6 N-S-${\bar{6}}$ was stable after age 7.

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Studies on the population biology of some clonal plants in a coastal reclaimed land

  • Choung, Yeon-Sook;Joon-Ho Kim
    • The Korean Journal of Ecology
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    • 제14권3호
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    • pp.327-343
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    • 1991
  • Clonal growth and rhizome architecture of calmagrostis epigeios, were studied in a 15-year old coastal reclamed land. As c. epigeios patch grew from center to margin radially over time, concentric annuli were added. the radial increases of the mature patch were 80~130cm/yr. the patch ages of c. epigeios estimated by relationships between the diameter and is radial increament, were 1~6year old. There were the marked variations of density, phytomass, shoot height and inflorecence frequency with increasing age of rhizome system within the patch. the maximum performance occurred at 2-year-old concentric annuli of the patch. The growth phasic continuum with aging was divided into 5 grwth phases ; pioneer, building, matyre, senile and degenerate. The rhizome aging had a more significant effect on the inflorescence frequency than on the other attributes. new rhizomes tended to diverge from the direction of the parent ramet by sympodial growth. in a 1-year-old patch, average length of rhizome segment was 7cm, average number of internode was 6, and the tillering frequency was 27%. The tillering in the early stage resultd in the increase of shoot density and the producation of multibranching rhizome. as the result of that, circular patchwas formed in a year. The branching structure based on such facts was represented graphically in branching degree of 60 and 100. therefore, c. epigeios with clonal growth may establish and grow vigorously earlier than other glycophytes in high salt conditions such as the coastal reclaimed land.

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한국인 아동의 악안면 성장에 관한 두부방사선 규격사진 분석에 의한 누년적 연구 (A LONGITUDINAL CEPHALOMETRIC STUDY OF CRANIOFACIAL GROWTH OF KOREAN CHILDREN)

  • 박태수
    • 대한치과교정학회지
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    • 제14권2호
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    • pp.217-231
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    • 1984
  • Many investigators have studied the growth changes of craniofacial complex to obtain important informations and standard values with which attempts at prediction of growth and treatment results have been under exploration. The author analyzed 360 cephalometric roentgenograms of 40 boys and 50 girls taken from the ages of 6 to 9 to assess the growth changes of craniofacial complex and to establish Korean norms by Ricketts' analysis method. 17 Landmarks, 10 planes and 8 angles were plotted and measured by linearly and angularly. The results were as follows: 1. The author made the tables of means, standard deviations from the measured values. 2. The item which showed significant difference between males and females in longitudinal study was facial axis length. 3. Items which show significant changes during 3 years were cranial base length, facial axis length, lower incisor to APO, Upper molar to PTV in males, and cranial base length, facial axis length, upper molar to PTV in females. 4. The correlations between cranial base length and facial axis length to body height and weight were higher in males than in females throughout the items.

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제주 인근해역에 서식하는 전갱이(Trachurus japonicus Temminck et Schlegel)의 연령과 성장 (Age and Growth of Jack Mackerel Trachurus japonicus off Jeju Island, Korea)

  • 이동진;강수경;정경미;차형기
    • 한국수산과학회지
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    • 제49권5호
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    • pp.648-656
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    • 2016
  • The age and growth of jack mackerel Trachurus japonicus caught by large purse seine fishery were studied during August 2004 and May 2005. Otoliths of 472 fish were observed under reflected light, and translucent zones made on the post-rostrum axis were regarded as annual marks. Monthly changes in the marginal index indicated that the translucent zone was formed once a year, mainly in March-April, which was coincident with the peak spawning time of jack mackerel. The estimated ages were 0-6 years, corresponding to a fork length (FL) range of 13 to 38 cm. Most obtained individuals were 2-year-old fish, followed by 1-year-old fish. The mean fork length at age from otolith reading (sex combined) was applied to the von Bertalanffy equation and growth parameters were estimated: L = 38.29 cm FL, k = 0.31 years−1, t0 = −0.81 years.

우리나라 남해에 분포하는 붕장어(Conger myriaster)의 연령과 성장 (Age and Growth of Whitespotted Conger Conger myriaster in the Southern Coastal Waters of Korea)

  • 김영혜;이은희;김정년;최정화;오택윤;이동우
    • 한국수산과학회지
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    • 제44권6호
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    • pp.689-694
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    • 2011
  • Age and growth of whitespotted conger Conger myriaster were estimated using right sagittal otoliths from 495 fish collected from February, 2004, to January, 2005, in the southern coastal waters of Korea. Examination of the outer margin of the otoliths showed that opaque zones formed once a year and annual rings formed from April to June. The ages of the specimens examined ranged from 3 to 8 years. Whitespotted conger spawn from December to March. Allometry between preanal length and total weight can be expressed as $TW=0.0350{\times}PL^{2.9173}$ ($R^2=0.89$). There was no significant difference in allometry between females and males (P>0.05). The estimated VBF growth equation was $L_t=415.2(1-e^{-0.1457(t+0.4654)})$.

한국인 아동의 하악골 성장유형에 따른 안모변화에 관한 누년적 연구 (A LONGITUDINAL STUDY OF KOREAN CHILDREN'S PROFILE CHANGE IN RELATION WITH MANDIBULAR GROWTH PATTERN)

  • 김의환;유영규
    • 대한치과교정학회지
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    • 제15권2호
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    • pp.175-195
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    • 1985
  • Vertical and horizontal growth occur in the craniofacial complex which ensues continuous changes in facial morphology, until the end of active growth period. Longitudinal study for individual is essential, in the research on growth and development, however, the difficulties in obtaining long term subjects in Korea, the research has been limited. The author analyzed the cephalometric roentgenogrems of 43 boys and 47 girls taken from the ages 6 to 10. The subjects were divided into 3 groups according to SN-MP angle and 2 groups according to gonial angle. In this longitudinal study, 21 variables were measure 4. The obtained results were as follows: 1. SN-MP angle and genial angle had no significant changes in each group with age. 2. With age, facial convexity of hard tissue decreased in all groups, facial angle of hard tissue increased in low SN-MP angle group, but facial convexity of soft tissue had no significant changes in all groups with age. 3. In comparison of high SN-MP angle group and low SN-MP angle group, the former had greater facial convexity and smaller facial angle than the latter. 4. SN-MP angle and the ratio of posterior dental height to anterior dental height had reverse correlation in all groups. 5. High genial angle group revealed larger SN-MP angle, anterior dental height facial convexity, but smaller mandibular length, and the ratio of posterior dental height to anterior dental height compared with low genial angle group.

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Development of an index that decreases birth weight, promotes postnatal growth and yet minimizes selection intensity in beef cattle

  • Kenji Togashi;Toshio Watanabe;Atsushi Ogino;Masakazu Shinomiya;Masashi Kinukawa;Kazuhito Kurogi;Shohei Toda
    • Animal Bioscience
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    • 제37권5호
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    • pp.839-851
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    • 2024
  • Objective: The main goal of our current study was to improve the growth curve of meat animals by decreasing the birth weight while achieving a finishing weight that is the same as that before selection but at younger age. Methods: Random regression model was developed to derive various selection indices to achieve desired gains in body weight at target time points throughout the fattening process. We considered absolute and proportional gains at specific ages (in weeks) and for various stages (i.e., early, middle, late) during the fattening process. Results: The point gain index was particularly easy to use because breeders can assign a specific age (in weeks) as a time point and model either the actual weight gain desired or a scaled percentage gain in body weight. Conclusion: The point gain index we developed can achieve the desired weight gain at any given postnatal week of the growing process and is an easy-to-use and practical option for improving the growth curve.

중부 영남육괴 김천일대 선캠브리아기 편마암의 저어콘 화학연대 (Zircon chemical age of the Precambrian gneisses from Gimcheon area in the central Yeongnam massif, Korea)

  • 이호선;송용선;박계헌
    • 암석학회지
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    • 제11권3_4호
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    • pp.157-168
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    • 2002
  • 중부 영남육괴 김천일대는 대부분 화강 편마암과 그에 협재된 흑운모 편마암이 포획암 내지 잔류암의 형태로 산출된다. 이 지역 선캠브리아기의 기저지각 발달사를 이해하기 위해서는 절대연대자료가 필수적이나 그 자료가 부족한 실정이고, 기존의 연대자료 또한 야외산상과 일치하지 않기 때문에 저어콘에 대한 화학연대 측정을 실시하였다. 측정결과 구해진 화강 편마암의 1970$\pm$78($l\sigma$)Ma와 흑운모 편마암의 둥근 저어콘의 외각부와 길쭉한 저어콘에서 각각 얻어진 $1814\pm$77($l\sigma$)Ma 및 $1973\pm$97(1$\sigma$)Ma 연대는 화강암질 마그마의 관입과 이에 의한 변성작용을 나타내는 것으로 판단된다 그리고 흑운모 편마암의 둥근 저어콘 중심부의 누대들이 보여주는 $2954\pm$158($l\sigma$)Ma, $2440\pm$58(l$\sigma$)Ma, $2219\pm$36(l$\sigma$)Ma 연대들은 흑운모 편마암의 변성작용 이전의 여러 지질사건들을 반영한 것이다 그리고 두 편마암의 저어콘 모두에서 나타나는 1450~1630Ma 연대는 화강 편마암과 흑운모 편마암이 함께 겪은 후기 변성작용의 시기로 생각된다. 이 연구에서 사용한 것과 같은 1 $\mu\textrm{m}$의 분석직경을 갖는 전자현미분석법에 의한 저어콘 화학연대 측정은 우수한 공간분해능의 결과로 복잡한 성장역사를 갖는 저어콘으로부터 지질학적 사건들을 구분하는데 아주 유용한 연대측정 수단으로 판단된다.

Simultaneous determination and difference evaluation of 14 ginsenosides in Panax ginseng roots cultivated in different areas and ages by high-performance liquid chromatography coupled with triple quadrupole mass spectrometer in the multiple reaction-monitoring mode combined with multivariate statistical analysis

  • Xiu, Yang;Li, Xue;Sun, Xiuli;Xiao, Dan;Miao, Rui;Zhao, Huanxi;Liu, Shuying
    • Journal of Ginseng Research
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    • 제43권4호
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    • pp.508-516
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    • 2019
  • Background: Ginsenosides are not only the principal bioactive components but also the important indexes to the quality assessment of Panax ginseng Meyer. Their contents in cultivated ginseng vary with the growth environment and age. The present study aimed at evaluating the significant difference between 36 cultivated ginseng of different cultivation areas and ages based on the simultaneously determined contents of 14 ginsenosides. Methods: A high-performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometer (MS) method was developed and used in the multiple reaction-monitoring (MRM) mode (HPLC-MRM/MS) for the quantitative analysis of ginsenosides. Multivariate statistical analysis, such as principal component analysis and partial least squares-discriminant analysis, was applied to discriminate ginseng samples of various cultivation areas and ages and to discover the differentially accumulated ginsenoside markers. Results: The developed HPLC-MRM/MS method was validated to be precise, accurate, stable, sensitive, and repeatable for the simultaneous determination of 14 ginsenosides. It was found that the 3- and 5-yr-old ginseng samples were differentiated distinctly by all means of multivariate statistical analysis, whereas the 4-yr-old samples exhibited similarity to either 3- or 5-yr-old samples in the contents of ginsenosides. Among the 14 detected ginsenosides, Rg1, Rb1, Rb2, Rc, 20(S)-Rf, 20(S)-Rh1, and Rb3 were identified as potential markers for the differentiation of cultivation ages. In addition, the 5-yr-old samples were able to be classified in cultivation area based on the contents of ginsenosides, whereas the 3- and 4-yr-old samples showed little differences in cultivation area. Conclusion: This study demonstrated that the HPLC-MRM/MS method combined with multivariate statistical analysis provides deep insight into the accumulation characteristics of ginsenosides and could be used to differentiate ginseng that are cultivated in different areas and ages.

Association of Insulin-Like Growth Factor-I (IGF-I) Gene Polymorphism with Serum IGF-I Concentration and Body Weight in Korean Native Ogol Chicken

  • Seo, D.S.;Yun, J.S.;Kang, W.J.;Jeon, G.J.;Hong, K.C.;Ko, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권7호
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    • pp.915-921
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    • 2001
  • IGF-I is involved in the regulation of growth and differentiation in mammals, but its role as a modulator of growth and metabolism in poultry is poorly understood. And, no studies have so far been reported for the comparison between serum IGF-I concentration and body growth in the egg type or the dual purposes (meat and egg type) chicken including the Korean Native Ogol Chicken (KNOC). Therefore, in order to improve the body growth and meat production of the KNOC, this study was conducted for the identification of the polymorphism of IGF-I gene and for its possible association with both body weight and IGF-I concentration. The RFLP patterns for IGF-I gene were identified by the PstI restriction enzyme. The frequencies of +/+, +/-, and -/- genotype were 16.9%, 51.7%, and 31.4%, respectively. Any statistical significance was not observed in all variations except for sex variation (p<0.01) by covariate quadratic model. The significant effect of the IGF-I genotype on body weight by sex indicates that there are different physiological characteristics in gender. Although the body weights of male KNOCs in most ages were not significant, there was a tendency of KNOCs with +/+ IGF-I genotype to be heavier than those with any other genotypes. But all IGF-I genotypes in female did not influence on body weight. The ANOYA revealed no significant effects of IGF-I genotypes on serum IGF-I concentration but sex effect was highly significant on the IGF-I concentration at 20 and 40 weeks (p<0.01). Although the +/+ genotype, in gender, tended to express a higher IGF-I concentration than the other genotypes at all ages in males, a statistical difference among the genotypes was not found except for 60 weeks (p<0.05). Furthermore, since body weight and IGF-I genotypes are associated, it is possible to improve KNOC to a meat type breed if a continuous selection can be made for the body weight and/or IGF-I traits.