• Title/Summary/Keyword: Ontogeny

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Histological and immunohistochemical studies on the colo-rectum of the chicken embryos (닭 태자의 직결장에 대한 조직학적 및 면역조직화학적 연구)

  • Lee, Jae-hyun;Ku, Sae-kwang;Lee, Hyeung-sik;Park, Ki-dae
    • Korean Journal of Veterinary Research
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    • v.38 no.4
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    • pp.696-703
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    • 1998
  • Histological changes and ontogeny, distribution and relative frequency of bovine SP-1/chromogranin(BCG)-, serotonin-, human pancreatic polypeptide(HPP)- and glucagon-immunoreactive cells were investigated in the colo-rectum of the chicken embryos. The pseudostratified columnar-like epithelium was observed in 10 days of incubation to 15 days of incubation, thereafter these epithelium were differentiated to simple columnar epithelium and goblet cells were detected for the first time on 19 days of incubation. BCG and serotonin-immunoreactive cells were observed for the first time on 15 days of incubation respectively, thereafter these cells were increased with ages. However no HPP and glucagon-immunoreactive cells were found in this study.

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Ontogeny of Haustorial Xylem in Parasitic Angiosperm Cuscuta austrailis R. Brown (기생피자식물 실새삼(Cuscuta australis R. Brown)의 흡기내 목부의 개체발생)

  • 이규배
    • Journal of Plant Biology
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    • v.34 no.2
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    • pp.137-144
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    • 1991
  • 기주식물 (토끼풀, Trifolium repens L.)에 기생하는 실새삼(Cuscuta australis R. Brown)의 흡기내 목부의 개체발생 과정을 광학현미경으로 조사하였다. 흡기의 목부 분화를 암시하는 최초의 해부학적 특징이, 흡기 자체내에서가 아니라, 그 흡기가 형성되어 있는 실새삼 줄기에서 나타났다. 즉 실새삼 줄기의 중심주의 유관속 내부 및 유관속 사이에서 세포분열 활성이 관찰되었다. 이 분열로부터 유도된 세포들은 짙게 염색된 세포질과 뚜렷한 핵을 갖고 있었다. 흡기가 기주조직에 침입하여 생장함에 따라, 실새삼 줄기의 중심주에서 시작된 세포분열 활성은 유관속 사이를 거쳐서 흡기의 기부를 향하여 구정적으로 확장되었다. 이와 동시에, 실새삼 줄기의 목부에 인접해 있던, 짙은 세포질 밀도를 갖는 세포들이 목부요소로 분화하기 시작하였다. 결국, 이미 형성되었던 짙게 염색된 세포들을 따라서 흡기의 목부는 구정적으로 분화하였다. 실새삼 줄기의 중심주에서 일어나는 유조직 세포들의 분열활성 및 이로부터 흡기의 목부 분화를 구정적으로 유도할 수 있는 가능성에 대하여 논의하였다.

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A Study on Implementation of Evolving Cellular Automata Neural System (진화하는 셀룰라 오토마타 신경망의 하드웨어 구현에 관한 연구)

  • 반창봉;곽상영;이동욱;심귀보
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.255-258
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    • 2001
  • This paper is implementation of cellular automata neural network system which is a living creatures' brain using evolving hardware concept. Cellular automata neural network system is based on the development and the evolution, in other words, it is modeled on the ontogeny and phylogeny of natural living things. The proposed system developes each cell's state in neural network by CA. And it regards code of CA rule as individual of genetic algorithm, and evolved by genetic algorithm. In this paper we implement this system using evolving hardware concept Evolving hardware is reconfigurable hardware whose configuration is under the control of an evolutionary algorithm. We design genetic algorithm process for evolutionary algorithm and cells in cellular automata neural network for the construction of reconfigurable system. The effectiveness of the proposed system is verified by applying it to time-series prediction.

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Ontogeny of the Fascicular Cambium in the Hypocotyl of Ricinus communis L. (피마자의 하배축에 있어서 유관속내 형성층의 초기발생)

  • 소웅영
    • Journal of Plant Biology
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    • v.32 no.4
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    • pp.305-312
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    • 1989
  • Developmental anatomy was conducted in order to elucidate the differentiating pattern of fascicular cambial initials in the hypocotyl of Ricinus communis. The homogeneous procambium with relatively short cells in early stage is transformed into a heterogeneous structure with long and short cells in late stage in tangential view. Fusiform and ray initials are gradually originated from the long and short cells of the procambium in hypocotyl in later stage respectively. Fusiform initials are not shorter than procambial cells because of the successive elongation of vascular meristematic cells. Therefore, the distinction between procambium and fascicular cambium is not made from comparison with their cell length. The characteristics of the fascicular cambium are gradully acquired at or just after completion of hypocotyl elongation.

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Copepodid Stages of Ergasilus hypomesi Yamaguti(Copepoda, Poecilostomatoida, Ergasilidae) from a Brackish Lake in Korea

  • Kim, Il-Hoi
    • Animal cells and systems
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    • v.8 no.1
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    • pp.1-12
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    • 2004
  • All copepodid stages and free-swimming adults of Ergasilus hypomesi Yamaguti collected from plankton samples from a brackish lake in Korea are described. The antennule remains a four-segmented appendage until copepodid V. The antenna of copepodid I carries a vestigial exopod. Sexual dimorphism first appears at copepodid IVwhose males bear primodial maxillipeds. Leg 5 also is sexually dimorphic from copepodid IV onwards, with its free segment bearing three setae in the female and two setae in the male. Morphological features of some appendages appearing during copepodid development are discussed. It is noticed that the early copepodids of the Ergasilidae show the characteristic setation on the biramous legs and proximal segments of the antennule.

9th Indo-Pacific Fish Conference Review

  • Gwak, Woo-Seok
    • Korean Journal of Ichthyology
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    • v.25 no.3
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    • pp.182-184
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    • 2013
  • The 9th Indo-Pacific Fish Conference (IPFC9) was held in Okinawa, Japan from 24th to 28th June 2013. Five hundred and thirty two delegates from 36 countries/regions around the world attended. The Conference took place with a welcome address by Dr. Keiichi Matsuura in the Laguna Garden Hotel next to the Okinawa Convention Center in the evening of 23rd June 2013, one day before the official start of the IPFC9. The winners of the two IPFC9 Bleeker Awards, Jeffrey M. Leis (Ecology) and Gerald R. Allen (Systematics) provided excellent talks on "Change in the early life-history of Indo-Pacific Fishes" and "The center of Indo-Pacific reef fish diversity". A total of 462 papers were presented, including 328 oral and 134 poster presentations. The main themes of IPFC9 included systematics, evolution, zoogeography and phylogeography, biodiversity, ecology, behavior, and conservation. There were 14 symposia, which included topics such as "Top predatory fish in the Indo-Pacific ecosystems", "Fish diversity across environmental extremes", "Ontogeny and systematics of Indo-Pacific fishes", and "Phylogenetics and diversification of the Percomorpha". IPFC10 will be held in Papeete, Tahiti.

Origin and Development of Fascicular Cambium in Hypocotyl of Eucommia ulmoides Seedlings (두충나무 유식물의 하배축에서의 유관속내 형성층의 기원 및 발생)

  • 강재선
    • Journal of Plant Biology
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    • v.36 no.3
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    • pp.275-279
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    • 1993
  • The early ontogeny of the vascular cambium in the hypocotyl of Eucommia ulmoides seedling was studied anatomically. In transverse view, the procambial cells repeated periclinal divisions and then gradually differentiated into vascular cambium; however, in the transectional plane, it was difficult to reveal the origin of cambial initials. In tangential view, the early procambial cells repeated periclinal divisions and then the procambium consisted of homogeneous short cells. Some cells in late procambium did not show transverse divisions, but elongated continuously. Thus, the procambium showed a heterogeneous structure: The long cells became fusiform initials with tapering end walls and the short cells differentiated into ray initials. Conclusively, the two types of cambial initials were gradually originated from the homogeneous cells at the early procambial stage, and they consisted vascular cambium.

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Structure, Ontogeny and Biology of Nectaries in Luffa acutanqqula (L.) Roxb. var. amara (Lam.) Cl.

  • Haran Iyer, K.R.P.;Subramanian, R.B.;Inamdar, J.A.
    • Journal of Plant Biology
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    • v.32 no.2
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    • pp.101-107
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    • 1989
  • Luffa acutanqula var. amara exhibits floral and extrafloral nectaries. The floral nectaries are restricted to the torus of the male flowers, while the extrafloral nectaries are observed on foliage leaves, probract, outer surface of calyx and pedicels. The floral nectaries develop from a group of epidermal and sub-epidermal initials which differentiate into secretory and subsecretory zones respectively during further divisions. The extrafloral nectary initiates from a single papillate nectary initial which gives rise to mature nectary comprising stalk layer, secretory and subsecretory tissues. Both the floral and extrafloral nectaries are vascularized. Interactions between insect-visitors and the plant with special reference to their functions are also discussed.

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Behavior Control of Autonomous Mobile Robots using ECANS1 (진화하는 셀룰라 오토마타를 이용한 자율이동로봇군의 행동제어)

  • Lee, Dong-Wook;Chung, Young-June;Sim, Kwee-Bo
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2183-2185
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    • 1998
  • In this paper, we propose a method of designing neural networks using biological inspired developmental and evolutionary concept. The living things are best information processing system in themselves. One individual is developed from a generative cell. And a species of this individual have adapted itself to the environment by evolution. Ontogeny of organism is embodied in cellular automata and phylogeny of species is realized by evolutionary algorithms. The connection among cells is determined by a rule of cellular automata. In order to obtain the best neural networks in the environment, we evolve the arrangement of initial cells. The cell, that is neuron of neural networks, is modeled on chaotic neuron with firing or rest state like biological neuron. A final output of network is measured by frequency of firing state. The effectiveness of the proposed scheme is verified by applying it to navigation problem of robot.

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Ontogenetic variation in Chironomus flaviplumus (Diptera, Chironomidae) larvae

  • Hyunsu Yoo;Jae-won Park;Ihn-Sil Kwak
    • Journal of Species Research
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    • v.13 no.1
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    • pp.41-49
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    • 2024
  • Chironomus is a large genus of Diptera comprising about 400 species and occurs worldwide except for Antarctica. The strong morphological cross-taxon similarity of chironomid larvae renders identification at the species level difficult. Here, we analyzed the morphology of larvae of Chironomus flaviplumus, an easily cultured species employed as a bioindicator in polluted environments, to determine identifying morphological characteristics at the first through fourth instar. Observed differences appearing at each instar include the presence or absence of setae on the body and tubules on the 10th and 11th body segment, the number of seta interna in the mandible, and the presence or absence of ring organs in the antennae. Some specific morphological characteristics did not change after hatching. Our findings provide a reliable method for identifying C. flaviplumus larvae.