• 제목/요약/키워드: Age and Growth

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A Special Case of a Two-Sex Model in the Growth of Population

  • Tae Ryung Park
    • Communications for Statistical Applications and Methods
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    • 제4권1호
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    • pp.207-218
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    • 1997
  • We consider two models for the growth of population with overlaping generations. First, the model we will describe is basically the model given by Leslie(1945). This is only a one-sex model of population age structure and growth. Next, we introduce a model in which couples must be formed before reproduction occurs. If the maximum number of couples is formed, and if the couples are only formed from fermales of age x-a and males of age x at time t, $\alpha$ > 0. Then, we will solve the renewal equations for the reproductive value.

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한국산 날망둑속(屬) 3종(種) (망둑어과(科))의 연령과 성장 (Age and Growth of Three Species of Genus Gymnogobius from Korea)

  • 김영자;김종만
    • 한국어류학회지
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    • 제13권4호
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    • pp.237-247
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    • 2001
  • 강원도 삼척시 호산리 호산천에서 채집된 꾹저구, 검정꾹저구, 무늬꾹저구 3종의 연령과 성장에 관하여 조사하였다. 체장 빈도 분포 조사에 의한 성별 성장조사에서 꾹저구의 당년생 수컷이 암컷보다 컸던 경우를 제외하고는 차이가 없었으나, 종간(種間)비교에서는 차이를 나타내었다. 즉, 꾹저구는 체장 45 mm 미만 집단이 당년생, 45~60 mm 집단이 1년생, 체장 60~80 mm 집단은 2년생, 80 mm 이상 집단은 3년생으로 추정되며 최대 체장은 105.0 mm였다. 검정꾹저구는 체장 55 mm 미만 집단이 당년생, 55~65 mm 집단은 1년생, 65~85 mm 집단은 2년생, 85 mm 이상 집단은 3년생으로 추정되며 최대 체장은 105.3 mm였다. 무늬꾹저구는 체장 40 mm 미만 집단이 당년생, 40~55 mm 집단은 1년생, 체장 55~75 mm 집단은 2년생, 체장 75 mm 이상은 3년생으로 추정되며 최대 체장은 85 mm를 넘지 않았다. 본 조사에서 만 4년생 이상되는 개체는 채집되지 않았고 암수간에 성장은 비슷하였다. 3종(種) 중 검정꾹저구가 모든 연령에서 다른 2종보다 성장이 약 5~10 mm 더 빨랐던 반면, 무늬꾹저구는 가장 느린 성장을 나타내었다 (p<0.0001). 체장의 성장에 따른 몸 부위의 형태적 변화를 공분산분석으로 비교검토해 본 결과, 종간(種間) 차이가 인정된 형질은 체고, 두장, 미병고, 상악장, 배지느러미의 길이였다. 즉, 꾹저구는 두장과 배지느러 길이에서 연령이 증가할수록 가장 빠른 성장을 나타내었고 검정꾹저구는 체고, 미병고, 상악장의 형질에서 가장 빠른 성장을 한 반면, 무늬꾹저구는 5개의 형질 모두 가장 느린 성장을 하였다.

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통영바다목장에 서식하는 조피볼락, Sebastes schlegeli의 연령과 성장 (Age and Growth of Black Rockfish, Sebastes schlegeli in the Tongyeong Marine Ranching Area in Korea Waters)

  • 박경동;강용주
    • 한국어류학회지
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    • 제19권1호
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    • pp.35-43
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    • 2007
  • 본 연구는 2001년 7월부터 2004년 5월까지 29개월동안 매월 경상남도 통영 바다목장해역에서 채집된 총 1,173마리의 조피볼락의 이석을 사용하여 연령과 성장을 연구하였다. 윤문은 불투명대에서 투명대로 이행되는 7월에 형성되었다. 주성숙기는 1월이며 산출시기는 2~5월 사이로 조피볼락의 초륜이 형성되는 시간은 주성숙기인 1월부터 이듬해 7월까지 약 1.5년으로 사료된다. 추정된 조피볼락의 von Bertalaffy length식과 weight growth equation식은 암컷은 $L_t=48.45(1-e^{-0.2139(t+0.4313)})$, $W_t=1,837.93(1-e^{-0.2139(t+0.4313)})^{3.02}$이었으며 수컷은 $L_t=49.32(1-e^{-0.1775(t+0.7403)})$, $W_t=1,887.83(1-e^{-0.1775(t+0.7403)})^3$였다.

Characteristics on the Physical Growth of Children and Youth in Modern Korea

  • Kim, Myung;Kim, Hye-Kyeong
    • 보건교육건강증진학회지
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    • 제23권5호
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    • pp.13-27
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    • 2006
  • This study was performed to formulate the most recent traits of physical growth of youth, and to identify the need of youth for health promotion planning in modern Korea. Study participants were 171 boys and 400 girls in two senior high schools in Seoul, Korea. Health records were collected from the individual students in May 2005. Longitudinal data on stature and body weight from 6 to 16 years old were analysed. Significance tests on some measures were performed by t-test and ANOVA. Major conclusions were as follows: 1. Girls were taller than boys during the specific time of adolescence. However, this phenomenon was not found in the growth process investigated by peak age and in over-all mean growth process of body weight. 2. Peak age came later in boys than in girls in both stature and body weight. This meant that boys matured later in stature and body weight than girls. However, boys were larger in peak velocity than girls. 3. Peak ages distributed more widely in girls than in boys both for stature and body weight. 4. Even in such short growth process from 6 through 16 years old, growth spurt tended to appear in several times. 5. Growth spurt tended to appear more often in boys than in girls.

Effects of age on intestinal phosphate transport and biochemical values of broiler chickens

  • Li, Jianhui;Yuan, Jianmin;Miao, Zhiqiang;Guo, Yuming
    • Asian-Australasian Journal of Animal Sciences
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    • 제30권2호
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    • pp.221-228
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    • 2017
  • Objective: The objective of this experiment was to characterize the mRNA expression profile of type IIb sodium-inorganic phosphate cotransporter (NaPi-IIb) and the biochemical values of serum alkaline phosphatase (AKP), calcium, inorganic phosphorus, tibial ash and minerals of broiler chickens with aging. Methods: A total of 56 one-day-old Arbor Acres male broiler chickens were used. Broiler chickens were weighed and samples were collected weekly from day 1. Results: The result showed that before the growth inflection point, ash, calcium, and phosphorus content in the tibia of broiler chickens increased with growth (before 3 weeks of age), although there were no significant differences in chicks at different ages in the later period of the experiment and weight gain rate was relatively slow at this stage (4 to 6 weeks). NaPi-IIb gene expression in the small intestine in the early growth stage was higher than that in the later growth stage. Expression of calbindin and the vitamin D receptor protein in the intestinal mucosa increased with age in the duodenum and jejunum. Serum AKP activity first increased and subsequently decreased after peaking at 1 week of age, but there was no significant difference after 3 weeks of age. Conclusion: These results show that compared with the early growth stage, the weight-gain rate of broiler chickens in the late growth stage gradually decreased with gradual tibia maturation, along with weaker positive transport of phosphorus in the intestine and reinforced re-absorption of phosphorus in the kidney, which might be the reason that phosphorus requirement in the late growth stage was decreased.

일부도시지역(一部都市地域)의 중고교생(中高校生)들의 성장(成長) 발육(發育) 및 체격지수(體格指數)에 관(關)한 조사연구(調査硏究) (A Study on Physical Growth and Development of High School Students in an Urban Area)

  • 박양원;이병갑;박순영
    • Journal of Nutrition and Health
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    • 제4권4호
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    • pp.29-38
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    • 1971
  • A survey on 4,117 (Boys:2,004, Girls:2,113) High School students in an urban area was conducted for assessing their physical growth, development and nutritional status from may throuth june 1971, and the following results were obtained. 1. Physical Growth and Development. a) Maximum growth was seen during the period from 12 to 16 years of age. b) The Maximum annual growth rates were as follows; Height: Boys-8.1cm from 14 to 15 years of age Girls-4.7cm from 13 to 14 Weight: Boys-8.0kg from 14 to 15 Girls-4.5kg from 13 to 14 Chest Girth: Boys-6.1cm from 14 to 15 Girls-4.2cm from 13 to 14 Sitting Height: Boys-4.6cm from 14 to 15 Girls-2.5cm from 13 to 14 c) The greatest individual differences in growth and development were observed during 12-15 years of age. d) Korean students were shorter than Japanese in 12-16 years of age group but after 17, Korean students become taller than Japanese. e) The standards of growth of rescent urban korean students show much improved than that of 1955. 2. Various Indices about Physical Growth and Development. a) Relative body weight was increased steadily annually and the crossing point of boys and girls appeared at age 11 at which girls surpassed boys and at 14, boys surpassed girls. b) Relative chestgirth showed narrow chest style in boys from 11 to 15 and from 11 to 14 in girls. c) The average relative sitting height was 54.0 in both sexes. d) The $R\ddot{o}hrer$ index was 1.1 in boys and 1.2-1.3 in girls. e) The Kaup index was lower than 2.0 in boys from 11 to 16 and in girls from 11 to 14. It becomes higher than 2.0 after 17 in boys but in girls after 15.

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한국 서해 문치가자미(Marbled Sole, Pseudopleuronectes yokohamae)의 성숙과 성장 (Maturity and Growth of Marbled Sole, Pseudopleuronectes yokohamae in the West Sea of Korea)

  • 황선완;황학빈;황선도
    • Ocean and Polar Research
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    • 제39권4호
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    • pp.279-292
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    • 2017
  • We determined the maturity and growth of the Marbled sole, Pseudopleuronectes yokohamae based on monthly sampling in the West Sea of Korea from February 2009 to December 2010. Determination of sex of P. yokohamae was by gonadal inspection, and age and growth were determined by analyzing the otolith. The biological minimum size of P. yokohamae female was 24.5 cm. The seasonal changes in the ratio of a translucent zone to an opaque zone revealed that the end of the translucent zone of the otolith were annuli formed in May once a year. We compared 8 type growth equations with several length-at-age data. By using the length-at-monthly age data of these, the calculated von Bertalanffy growth equations were $L_t=41.7(1-e^{-0.47(t+0.24)})$ for females and $L_t=32.7(1-e^{-0.75(t+0.01)})$ for males. We estimated that 24.5 cm was the total length of 2 year old P. yokohamae spawns in the cold water season from January to April, and grows to 8 years old for females and 6 years old for males in the West Sea of Korea.

대기오염으로 교란된 여천공단 주변 소나무군락의 재생 (Regeneration of Pinus densiflora Commuity around that Yeocheon Industrial Complex Disturbed by Air Pollution)

  • Lee, chang Seok
    • The Korean Journal of Ecology
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    • 제16권3호
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    • pp.305-316
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    • 1993
  • Stands profiles, yearly changes in growth of annual rings, age and diameter structure, and spatial distribution pattern of individuals in the Pinus densiflora stands around the Yeocheon industrial complex were investigated. Growth of annual ring in Pinus densiflora, which survived when vegetation of this area was damaged by air pollutants, was suppressed for about 10 years since 1974 when factories in this area began to operate, but since then such suppressed growth tended to be recovered. It was supposed that the suppresed growth was originated from air pollution and that improvement of growth since the suppressed period was due to the release from competition with them by death of neighbouring trees and the resuction of the amount of air pollutants. Physiognomy of Pinus densiflora stands showed mosaic pattern composed of different patches. Spatial distribution pattern of individuals an stand profiles were similar to those of Pinus densiflora stands regenerated after natural and artificial disturbances. In an age distribution diagram, age of Pinus densiflora population ranged from 1 to 33 years, Among these individuals were recrited corresponded to the suppresed period of growth of annual ring in Pinus densiflora survived when the vegetation was damaged by air pollution. On the other hand, from the result of analysis of frequency distribution diagram of diameter, it was postulated that even if whis Pinus densiflora community can be maintained as it is for the time being, it might be changed to Quercus community with the lapse of time.

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경조직측모(硬組織側貌)의 성장변화(成長變化)에 관(關)한 누년적(累年的) 연구(硏究) -7세(歲)부터 11세(歲)까지의 연구(硏究) 보고(報告)- (A LONGITUDINAL STUDY ON THE BONY FACIAL PROFILE CHANGES - Study Report from 7 to 11 years of age -)

  • 이정분
    • 대한치과교정학회지
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    • 제8권1호
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    • pp.49-58
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    • 1978
  • This investigation was undertaken to know how the bony facial profile could be changed with age. The 5 serial lateral cephalometric roentgenograms of the fourteen boys and fourteen girls between 7 and 11 years of age were studied and the findings seems to warrant the following conclusions. 1. The manaible tended to become more prognathic in relation to the cranial base (S-N) during growth, but the maxilla showed very little change. 2. There was increase in the inclination of the lower border of mandible associated with the increase in mandibular prognathism. 3. There was a tendency to being straight in bony facial profile due to the decrease in angle ANB with age. 4. The chin portion had a tendency to forward and downward growth in relation to the cranial base but there was slight strong tendency in downward growth. 5. The vertical growth was more prominant in the maxilla than in the mandible. 6. There was uniform and gradual increase of all measurements during growth. 7. Dimension of the craniofacial complex was larger in the boys than in the girls but this difference was not statistically significant. 8. Individual variation in skeletal growth was a normal occurrence.

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한의 성장 치료에 따른 성장 지표 변화 (Change of Growth Indicators by the Treatment of Korean Medicine)

  • 오혜인;이현희;정지은;이혜림
    • 대한한방소아과학회지
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    • 제37권3호
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    • pp.35-48
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    • 2023
  • Objectives We aimed to analyze changes in growth indicators before and after Korean medicine treatment in patients treated at the pediatric department of a hospital. Methods We analyzed the medical records of children and adolescents under 18 years of age who underwent growth assessment between January 1, 2017 and December 31, 2022. Results A total of 21 patients were selected for this study. After treatment, there was a significant increase in the height percentile, whereas bone age-chronological age (BA-CA) and predicted adult height (PAH) did not show significant changes. No major adverse reactions were observed during the treatment. Growth reassessment was conducted twice for 10 participants. When comparing the growth indicators between the assessment sessions, the height percentile showed an increasing trend between the initial and the first growth reassessment. However, there were no significant differences between BA-CA and PAH across the different assessment periods. Conclusions There is a need to establish evidence for the efficacy and safety of continuous Korean medicine growth treatment through the long-term observation of growth indicators in patients undergoing treatment for two or more periods, as well as observational studies on liver and renal function indicators.