• Title/Summary/Keyword: early life history

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Early Life History of Rhodeus Fish (R. uyekii and R. ocellatus) in the Nakdong River Water System

  • Park, Jae-Min;Han, Kyeong-Ho
    • Development and Reproduction
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    • v.22 no.1
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    • pp.39-53
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    • 2018
  • The purpose of this study is to investigate the early life history of the Rhodeus fish, Rhodeus uyekii and R. ocellatus, in the Nakdong River to use as the preliminary data for the systematic study. The embryos used in the study were fertilized eggs (embryo) and larvae after artificial fertilization. The long diameter of the eggs of the R. uyekii was 3.39-3.97 mm (average $3.68{\pm}0.41mm$, n=30) and the short diameter was 1.36-1.55 mm (average $1.45{\pm}0.13mm$, n=30). The long diameter of the eggs of the R. ocellatus was 2.53-2.71 mm (average $2.62{\pm}0.12mm$, n=30) and the short diameter was 1.47-1.60 mm (average $1.53{\pm}0.09mm$, n=30). Hatching time was 48 hours for the R. uyekii and 50 hours for the R. ocellatus given that the average water temperature was $21.5^{\circ}C$. The hatched larvae were 4.95-5.00 mm (average $4.98{\pm}0.04mm$, n=5) for the R. uyekii and the total length was 3.66-3.69 mm (average $3.67{\pm}0.02mm$, n=5) for the R. ocellatus. R. uyekii was found to be 15.5-15.8 mm at total length (average $15.6{\pm}0.21mm$, n=5) on the 56 days after hatching with the number of dorsal fins being ⅲ-9, anal fins ⅲ-10, ventral fins ⅲ-5. The R. ocellatus was found to be 15.8-16.0 mm (average $15.9{\pm}0.14mm$, n=5) at total length on the 58 days with the number of dorsal fins being ⅲ-11, anal fins ⅲ-12 and ventral fins ⅲ-5 where the number of all fin stalks reached maximum.

Morphological Development of Egg and Larvae of Iksookimia choii (Cobitidae) (미호종개 Iksookimia choii (Cobitidae)의 난 발생 및 자어 형태 발달)

  • Song, Ha-Yoon;Kim, Woo-Joong;Lee, Wan-Ok;Bang, In-Chul
    • Korean Journal of Ecology and Environment
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    • v.41 no.1
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    • pp.104-110
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    • 2008
  • The egg development and early life history of Korean endangered natural monument fish, Iksookimia choii, were investigated in 2006. The eggs from the females were obtained by injecting 10 IU $g^{-1}$ of human chorionic gonadotropin and inseminated by wet method in the laboratory. The fertilized eggs were $1.1\sim1.3mm$ in diameter and had no oil globules. Hatching of the embryo began about 24 hrs after fertilization under water temperature of $25^{\circ}C$. The newly-hatched larvae were $2.5\sim2.7mm$ in total length (TL), and their mouth and anus were not yet opened. Six days after hatching, the postlarvae were $4.7\sim5.4mm$ TL, and tip of the caudal notochord was flexed $45^{\circ}$ upward. The juveniles stage was reached when all fin-rays were formed at 35 days after hatching, and their total length were $20\sim22mm$.

Morphological of Development Eggs, Larvae and Juveniles Micropercops swinhonis in Botongcheon Stream Hangang River (한강 수계 보통천에 서식하는 좀구굴치 Micropercops swinhonis의 난발생 및 자치어 형태발달)

  • Jae-Min Park;Kyeong-Ho Han
    • Korean Journal of Ichthyology
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    • v.35 no.3
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    • pp.151-159
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    • 2023
  • This study investigated the early life history of the Micropercops swinhonis in Botongcheon stream Hangang River and compared the relationship between the related species and flexibility. The fertilized egg of the ovoid type, and the average egg diameter was 1.23 mm in long diameter and 0.85 mm in short diameter. At a water temperature of 20.6℃, the hatching time took 179 hours. The newly hatched larvae measured 3.82~4.08 mm in total length (TL), and their mouth and anus were not yet open. At 18 days after hatching, the postflexion larvae reached 7.97~8.43 mm in TL, with the tip of the caudal fin bent at 45°. At 29 days after hatching, the juveniles reached 9.83~10.8 mm in TL and were differentiated by their constant number of fins (7~10 first dorsal, 10~11 second dorsal, 7~10 anal fins). As a result of the study, there was a difference from the related species in the egg diameter, the newly hatched larva size. The postflexion larvae period and the development period of the first dorsal fin were the slowest among the comparable simila species, and the size was characterized by a large number, indicating a difference from similar species in the early life history process.

A Study on the Concept of Learning Environment According to the Philosophy of Child-Centered Education in Europe in the Early 20th Century (20세기 초 유럽의 아동중심 교육철학에 따른 학습환경 개념에 대한 고찰)

  • Rieu, Ho-Seoup
    • Journal of the Korean Institute of Educational Facilities
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    • v.24 no.1
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    • pp.11-22
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    • 2017
  • The main purpose of this research is to consider educational environment, concept, and spatial organization and its characteristic based on the early 20th century European child-centered educational philosophy. For this process, the study of the following have been done : 1) Literature review, which includes educational ideology, perspective of child development of Maria Montessori, Rudolf Steiner, Peter Peterson, and Celestin Freinet. 2) Comparisons of spatial organization and classrooms of schools operated with the educational philosophy of mentioned philosophers from above. These schools have classrooms(or multi-purpose space near classroom) contained self-directed individual learning space, group and collaborative learning space, and training space of practical life. These configuration of learning space intended 1) learning based on individual child's interest, experience 2) developing of responsibility based on freedom 3) sociality and community spirit of children.

Nature Death Act -Taiwan Experience-

  • Lai, Enoch Y.L.
    • 한국호스피스완화의료학회:학술대회논문집
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    • 2008.07a
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    • pp.19-21
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    • 2008
  • Hospice movement in Taiwan emerged early in 1983. There was a nurse visiting terminal cancer patients by herself in Taipei city. It was ceased after one year. This stage of hospice movement might be called as "compassionate era". In early 1990, the first in-patient hospice ward was set up in north Taiwan. She demonstrated high touch in the high technology medical atmosphere. There was a great echo in Taiwan society to this action. In the following years, quite a few new hospice settings were founded. Medical professionals were aroused again to talk and think about life and death, dignity of dying and holistic care. This stage of hospice movement might be called as "ethical stage". Around 2000, obstructions were discovered in our development. We do need system and rules. Standard of setting and care, Curriculum of education and training, Accreditation system and specialist system and Nature Death Act are some of the systems we approached. This stage of hospice movement might be called as "Act stage". Among the "Act stage", the Nature Death Act is actually the mile stone in our history. What listed below are the translated one for the reference:

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Embryonic Development and Early Life History of the Northern Loach, Cobitis pacifica (Pisces: Cobitidae) (북방종개 Cobitis pacifica(Pisces: Cobitidae)의 배 발생과 초기생활사)

  • Lee, Wan-Ok;Kim, Kyeong-Hwan;Baek, Jae-Min;Kang, Young-Jin;Jeon, Hyoung-Zoo;Kim, Chi-Hong
    • Korean Journal of Ecology and Environment
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    • v.44 no.1
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    • pp.1-8
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    • 2011
  • We investigated developmental stages of embryo and early life history of the Korean indigenous fish, the northern loach, Cobitis pacifica in 2009 in order to understand fundamental knowledges for conservation of this species. Eggs were obtained after hormones injections (LHRH-a, HCG) and were artificially fertilized by the dry method. The embryo was spherical, separative demersal, faint white, and averaged $1.09{\pm}0.04\;mm$ (n=20) in diameter. The hatching of the embryo took place in about 48 hours after fertilization under water temperature of $21.0{\sim}24.0^{\circ}C$ and the newly hatched larvae averaged $2.87{\pm}0.05\;mm$ (n=20) in total length (TL). Four days after hatching, the larvae grew up to $6.86{\pm}0.10\;mm$ (n=10) in TL and york sac absorption, mouth and anus opening were shown. Fourteen days after hatching, most of fin-rays appeared at $10.71{\pm}0.34\;mm$ (n=10) in TL and color spots on the body surface were attained. Twenty six days after hatching, the larvae grew up to $14.88{\pm}0.45\;mm$ (n=10) in TL, and all their fin-rays were formed. Therefore, according to current study regarding the morphological development of Cobitis pacidica, the conversion from larval to juvenile stages occurred at 26 days after hatching. Eighty days after hatching, the larvae were $33.3{\pm}1.25\;mm$ (n=10), and their body shape and color pattern were similar to adult fish. In this study, embryonic development and early life history of the northern loach, Cobitis pacifica show morphological characteristics of Cobitidae family. We expected that our results can be used as an fundamental knowledges for restoration study of indigenous fish species.

Ecological Characteristics of Paralebeda plagifera femorata (Lepidoptera: Lasiocampidae) in Korea (한국산 대만나방(나비목: 솔나방과)의 생태적 특성)

  • 심상준;이기영;황환준;한상섭;변봉규
    • Korean journal of applied entomology
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    • v.39 no.2
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    • pp.83-87
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    • 2000
  • This study was carried out to investigate the life history of Paralebeda plagifera femorata in 1998 and 1999. Ginkgo biloba was newly known to be a host plant for the species in this study. The moth has one generation a year. It overwinted as 6th instar larva on branches of the host plant. The 9th instar larva made a rough cocoon by webbing two or three leaves, and pupated on the branch on late June. The moths emerged from early July through early August with a peak around late July. A female oviposited 205 eggs on an average on the branch, twig, or leaf margin.

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An observational population based study on dysmenorrhea and its risk factors

  • Kotagasti, Tabassum;Rias, Nishad
    • CELLMED
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    • v.5 no.3
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    • pp.18.1-18.4
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    • 2015
  • Dysmenorrhea is the most common gynecological disorder in women of reproductive age. The prevalence of menstrual pain is relatively high and has been shown to be related to many factors like age, age at menarche, menstrual cycle regularity, parity, cigarette smoking, and dietary habits etc. This study was conducted to determine the possible link between dysmenorrhea and the factors related to it. We investigated the associated risk factors that could influence menstrual pain. This Cross Sectional Study was conducted at Dept. of OBG, NIUM, Bangalore. The study consisted of 230 women between the ages of 20 - 49 years. Included volunteers were newly married, nulliparious and parous women. The detailed reproductive history was recorded and was analyzed statistically. It was observed that there were only two factors that were influencing Dysmenorrhea namely the early age at menarche and increase parity. It was hypothesis that earlier start to reproductive life in some way decreases the sensitivity of the uterus to prostaglandin, whereas delayed menarche and postponing reproductive life increase sensitivity of the uterus to prostaglandins and cause severe menstrual pain. It is concluded that early age at menarche and high parity decrease menstrual pain.

Laparoscopic management of early primary peritoneal pregnancy: a case report

  • Koo, Hwa-Seon;Bae, Ju-Youn;Kang, Inn-Soo;Koong, Mi-Kyoung;Kim, Hye-Ok;Cha, Sun-Hwa;Choi, Min-Hye;Kim, Ji-Young;Yang, Kwang-Moon
    • Clinical and Experimental Reproductive Medicine
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    • v.38 no.2
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    • pp.109-114
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    • 2011
  • Peritoneal pregnancy is an implantation in the peritoneal cavity exclusive of tubal, ovarian, or intra-ligamentary implantations. This is a rare obstetric complication with high maternal mortality and even higher perinatal mortality, and secondary type was most common. Risk factors for peritoneal pregnancy are previous history of extrauterine pregnancy or tubal surgery pelvic post-inflammatory status or presence of an intrauterine device. As it is a life-threatening condition, expectant management carries a risk of sudden life-threatening intra-abdominal bleeding and a generally poor fetal prognosis. So, when it is recognized, immediate termination of pregnancy is usually recommended. Early diagnosis of peritoneal pregnancy is difficult, but is important by their life threatening progress course to patients. Recently, we experienced primary peritoneal pregnancy which meets both the original and modified criteria. In this paper, we reported the case of early diagnosed and successfully treated peritoneal pregnancy despite of their diagnosis was incidentally.

Design Positioning of the Korea Railway (한국철도차량의 디자인 포시셔닝)

  • Lee, Hee-Yup;Kim, Chang-Hyun
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1268-1275
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    • 2007
  • The Korea railway design trends has been developed by the change of the society and culture through the consideration of the history of railway. The railway design trends is as the vehicles in the external form of railways, instantly means to plan and create the value added something like the form of the exterior design. The railway design has been changing form instinctive methods to settle the mass transport of the early days, to sensitive methods to pursue the railway culture centering around human being. As dividing by the style's change of railway in image scale aspects between 1800's and 2005 according to the life environment into the external nation, there are big differences so that is to study the development history of the railway design accordingly each nation (Korea, United Kingdom, Germany, France, Japan) and the style's change, to confirm into the design applied in society and culture needs, and to analyze by a year in changes of the environment and the railway design history. This paper analyzed railway introduced as railway models by top 4 nation (United Kingdom, Germany, France, Japan) and Korea in the past years(1800-2005) for their Korea railway design trends by image scale positioning.

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