• Title/Summary/Keyword: 존재

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Electron Microscopic Study on the Role of Actin Filaments during the Formation of Bile Canaliculi in Isolated Rat Hepatocyte Culture System (흰쥐에서 분리 배양한 간세포의 담세관 형성에 있어서 액틴미세섬유의 역할에 관한 전자현미경적 연구)

  • Park, Chang-Hyun;Chang, Byung-Joon;Uhm, Chang-Sub
    • Applied Microscopy
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    • v.29 no.4
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    • pp.437-450
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    • 1999
  • Bile canaliculi are the structure delivering bile secreted by hepatocytes into the bile passage. Bile secretion is mainly controlled by the cytoskeletal elements, mainly of actin in the microvilli, pericanalicular web. Most studies on the bile secretion have been done in viva situation, however, to control the various parameters in vitro culture system seem to be more useful. To set up an in vitro experimental system, the investigator isolated hepatocytes with an enzymatic method using a mixture of collagenase and hyaluronidase from normal Sprague-Dawley rat liver and cultured. Isolated hepatocytes were round and formed cords in culture. Microvilli covered the whole surface of hepatocytes. Bile canaliculi were formed between hepatocytes and were characterized by the presence of microvilli of various lengths and shapes mainly arising from small surface mounds. Actin filament core in the microvilli and pericanalicular actin web were incomplete. After cytochalasin D treatment, cultured hepatocytes were round but the surface were irregular with surfacen blebs, folds and grooves. Microvilli on the surface were scarce. Bile canaliculi were markedly dilated often with the detached junctional complexes. Bile canaliculi lacks microvilli almost completely and extended into the pericanalirular cytoplasm showing complex vacuolar and tubular structures by transmission electron mciroscopy. Pericanalicular actin web, intermediate filaments were hardly identified. Subsurface actin filaments were scattered scarcely under the cell membranes. These results suggest that hepatocytes isolated from rats can survive and form bile canaliculi in culture and the actin filaments are involved in the formation and/or maintenance of the bile canaliculi.

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Choi Han-gi's Change of Ontological and Epistemological Paradigm (최한기의 존재와 인식에 관한 패러다임의 전환)

  • Rhee, Myung-Su
    • The Journal of Korean Philosophical History
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    • no.57
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    • pp.9-30
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    • 2018
  • The paradigm of existence and recognition was changed in the context of modernity in Choi Han-gi's thought, in which the resource of all things and all affairs was not li but ki and li could be guessed from ki. And there are lis in the sphere of recognition as well as in that of existence in Choi Han-gi's thought, which might be different from traditional thought system such as Neo-Confutionism. li is called Yuhaenguili in his ontological theory and Chucheukuili as one epistemological part. At anyhow there are many lis, which may be approached as the meaning of mechanism, in his philosophy. Besides there are, not only ontologically but also epistemologically, energetic factors, named as Unhwaki, whch are generating, moving, changing and altering. In his Kihak as an ki categorical thought, above all one's experience is of importance. He believed moral act, for example the expose of saving mind that was called Cheukeunjisim by Mencius, could be derived from social experience or contact. And he thought that the recognition of moral act might be achieved by the action of mysterious energy names as sinki of the essence of mind. Like these aspects, all things and all ones have their active, movable, and changeable natures in the sphere of both existence and recognition in Choi Han-gi's thought. In this way he got out of the previous ideas and presented practical and modern way of life to us.

Ch'oe Han-gi's Reflection on Relationalities in Existence (최한기의 존재론적 관계성 성찰)

  • Rhee, Myung-Su
    • The Journal of Korean Philosophical History
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    • no.59
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    • pp.395-423
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    • 2018
  • Since the middle of the 19th century, East Asia, especially Korea, was oppressed externally by the imperialism of Japan and others while internally long-lasting political convention like in-law government was driving the country into troubles at home and abroad. Witnessing such a situation and building up scholarly capability through reading over nearly all spheres, a Confucian philosopher, Ch'oe Han-gi (崔漢綺, 1803-1877), philosophized about the clue to the solution of such a choking phenomenon. Ch'oe believed that there was movement, ki (matter, material force, energy) of revolving transformation inherent in all things, people, or objects. Grasping even the principle and order of existence inherent in things from the viewpoint of ki, he tried to change the traditional theory on the law of existence of things that there existed an ontological reason lacking in motility, which was more dominant than anything existing in the universe and which ruled over the world. From this, he elucidated that the Way, an identity that rules over all affairs and things, was not simply one but diverse. This means, on one hand, that he tentatively accepted the relativity of things. On the other hand, he also taught us "oneness in all things" in which all including human beings exist in close connection to each other transcending the relativity or "agreement" in which they exist in harmony as one and "unity" in which they are united into one.

A Radical Change of Bergson's Theory of Duration: The Role of Future in the Constitution of Time (베르그손 <지속> 이론의 근본적인 변화: 시간 구성에 있어서 미래의 주도적 역할)

  • Jo, Hyun Soo
    • Journal of Korean Philosophical Society
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    • no.95
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    • pp.29-57
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    • 2011
  • Bergson's second work, matter and memory, shows a considerable change in his understanding of time's nature. There, time is no more something indivisible, the distinction of past and present being taken as it's essential feature. Bergson asserts that the past, by it's nature, is something that never ceases to be. His assertion of this immortality of the past leads many people to think that, for him, it's by virtue of the past that duration is possible. Deleuze, an excellent commentator of Bergson's thinking, constructs a really sophisticated argumentation to explain how this immortal ontological past makes possible the passage of time. But we think that the past, as well as the present, tends only to be spatialized, if it is left alone without the help of the future: the ontological past can not make possible time. We try to show how the future can save past and present from their inherent tendency of spatialization : it is by virtue of the future that time(duration) is possible.

Distributed Multicast Routing Algorithm for Non-Interactive Video/Audio Distribution (비상호적 비디오/오디오 분배를 위한 분산형 멀티캐스트 라우팅 알고리즘)

  • Yi, Yung;Lee, Young-Seok;Choi, Yang-Hee
    • Journal of KIISE:Information Networking
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    • v.28 no.4
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    • pp.508-516
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    • 2001
  • This paper proposes multicast routing algorithm that operates for non-interactive multimedia applications such as VOD(Video On Demand) and real-time data broadcasting. It is possible that there exist multiple senders in non-interactive multimedia applications. This paper designs multicast routing algorithm in this environment. The simulation of algorithm proposed in this paper shows much better performancetcost, delay) than that of only one source. To guarantee the performance of algorithm, Broadband ATM network is modelled in simulation.

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Similarity measures for trajectories of moving objects in cellular space (셀룰러 공간에 존재하는 이동객체 궤적의 유사성 측정)

  • Kang, Hye-Young;Kim, Joon-Seok;Hwang, Jung-Rae;Lee, Ki-Joune
    • Spatial Information Research
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    • v.16 no.3
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    • pp.291-301
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    • 2008
  • While most GIS are based on Euclidean space, cellular space can be used as an alternative type of space for a large number of GIS applications. In order to analyze the pattern of moving objects in cellular space, we need new definitions of similarity between their trajectories since the trajectory in cellular space significantly differs from those in Euclidean space. In this paper, we study the properties of moving objects in cellular space. Based on these observations, we propose several similarity measures between trajectories in cellular space. We analyze the difference of the proposed measures by experiments.

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Biological active components in cigarette mainstream smoke (담배연기 중 생물학적 활성 성분)

  • Shin, Han-Jae
    • Journal of the Korean Society of Tobacco Science
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    • v.32 no.1
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    • pp.41-54
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    • 2010
  • 담배 주류연은 수천가지 종류의 다양한 형태의 화학물질로 구성되어있고, 이들 화학물질의 대부분은 극히 미량의 농도로 존재하는 것으로 알려져 있다(Green and Rodgman, 1996). 담배연기 속에서 발암물질로서는 poly cyclic aromatic hydrycarbon (PAHs) 류인 B(a)P를 최초로 보고된 이후, 현재까지 69종의 화합물이 담배연기중의 발암물질로서 알려졌으며, 여기에는 9종의 PAHs 그리고 4종의 aromatic amine, nitrosoamines 및 aldehydes 그리고 다른 무기 및 유기 화합물들을 포함된다. 또한 담배 주류연에는 여러 화학물질들에 의해 유발된 생물학적 독성을 상당히 감소시키는 것으로 확인된 성분들이 존재하는 것으로 알려져 있다. 이러한 담배연기 중에 존재하는 항 발암성 효과를 나타내는 성분들의 작용 메카니즘은 발암성 물질 또는 발암성 물질의 대사산물들과 반응을 하거나, 불활성화 시키거나, 세포 구성 물질들과의 반응에서 서로 경쟁하거나, 또는 발암성의 흡수를 간섭함으로서 발암성 효과를 없애거나 또는 감소시키는 것으로 생각된다. 여러 연구자들은 담배연기 응축물에서 종양 성장의 억제 작용을 하는 성분들이 존재하는 것으로 주장 하고 있다.(Hoffmann and Griffin, 1958; Fall et al., 1964; Homburger and Tregier, 1965). 담배 연기 중에는 발암성을 나타내는 성분들과 함께 항 발암성 및 항 돌연변이성 효과를 나타내는 성분들이 존재한다는 것이 다양한 생물학적 평가 연구들에 의해 증명되었다(Slaga and DiGivanni, 1984; Fay et al., 1984; Green and Rodgman, 1996).

An Analytical Study to evaluate Existing Stress of Steel Structural Member (철골구조물의 존재응력 추정에 관한 해석적 연구)

  • Kim, Kap Sun;Shin, Eui Gyun;Kim, Woo Bum;Chung, Soo Yong
    • Journal of Korean Society of Steel Construction
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    • v.11 no.3 s.40
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    • pp.301-309
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    • 1999
  • The purpose of this study is to develop a method to deduce existing stress of steel member in inelastic range. Based on the previous experimental study, modified factor method considering the local plastification due to stress concentration was proposed. Finite element analysis was performed to investigate the stress distribution around hole and the results of the finite element analysis were compared with those from the Hole Drilling Method in elastic-plastic range. As a result of applying a modified factor method, proposed method shows very good approximation of 2% error for exact value of stress in the plastic range.

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Wave Damping Rate Over Multi-layer Permeable Bed of Finite Depth (깊이가 유한한 다중 투수층 위에서의 파의 감쇠율)

  • Suh, Kyung-Duck;Do, Ki-Deok
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.21 no.2
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    • pp.127-135
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    • 2009
  • Reid and Kajiura(1957) has studied on the wave damping rate over a permeable bed of infinite depth. In this study, wave damping rate over a permeable bed of finite depth is derived by linear wave theory. It is then extended to derive wave damping rates over a double or triple layer, each of which consist of different material. Applying the wave damping rate to the mild slope equation, the wave transmission coefficient over a permeable bed has been calculated. The model has been certificated by comparing with the result of Flaten and Rygg(1991)'s integral equation method in the case of a single-layer bed.