• 제목/요약/키워드: cell arrangement

검색결과 252건 처리시간 0.027초

Fine Structure of Cardiac Sarcomeres in the Black Widow Spider Latrodectus mactans

  • KIM, Hoon;MOON, Myung-Jin
    • Entomological Research
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    • 제48권5호
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    • pp.429-438
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    • 2018
  • Fine structural characteristics of the cardiac muscle and its sarcomere organization in the black widow spider, Latrodectus mactans were examined using transmission electron microscopy. The arrangement of cardiac muscle fibers was quite similar to that of skeletal muscle fibers, but they branched off at the ends and formed multiple connections with adjacent cells. Each cell contained multiple myofibrils and an extensive dyadic sarcotubular system consisting of sarcoplasmic reticulum and T-tubules. Thin and thick myofilaments were highly organized in regular repetitive arrays and formed contractile sarcomeres. Each repeating band unit of the sarcomere had three apparent striations, but the H-zone and M-lines were not prominent. Myofilaments were arranged into distinct sarcomeres defined by adjacent Z-lines with relatively short lengths of $2.0{\mu}m$ to $3.3{\mu}m$. Cross sections of the A-band showed hexagon-like arrangement of thick filaments, but the orbit of thin filaments around each thick filament was different from that seen in other vertebrates. Although each thick filament was surrounded by 12 thin filaments, the filament ratio of thin and thick myofilaments varied from 3:1 to 5:1 because thin filaments were shared by adjacent thick filaments.

An unusual arrangement between the highest denticulate ligament and posterior inferior cerebellar artery

  • Aditi Patel;Johnathan Baudoin;Arada Chaiyamoon;Juan J. Cardona;Ana Carrera;Francisco Reina;Joe Iwanaga;Aaron S. Dumont;R. Shane Tubbs
    • Anatomy and Cell Biology
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    • 제56권3호
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    • pp.394-397
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    • 2023
  • The posterior inferior cerebellar artery (PICA) is often involved in pathologies of the posterior cranial fossa. Therefore, a good understanding of the vessel's normal and variant courses is important to the neurosurgeon or neurointerventionalist. During the routine microdissection of the craniocervical junction, an unusual arrangement between the highest denticulate ligament and PICA was observed. On the right side, the PICA was given rise to by the V4 segment of the vertebral artery 9 mm after the artery entered the dura mater of the posterior cranial fossa. The artery made an acute turn around the lateral edge of the highest denticulate ligament to then recur 180 degrees and travel medially toward the brainstem. Invasive procedures that target the PICA should be aware of the variant as described herein.

독나방 (Euproctis flava BREMER) 유충의 발생소침과 독선세포에 관하여 (In the Urticating Spicule and the Gland Cell of the Larva in Euproctis flava BREMER(Lepidoptera))

  • 김창환
    • 한국동물학회지
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    • 제3권2호
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    • pp.1-4
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    • 1960
  • Urticating spicules and poison -secreting cells of the last instar larva in Euproctis flava BREMER was studied histologically. Three kinds of cells in the epidermis of tubercles on the lst to 8th abodominal segments are classified according to the arrangement of their nuclei : smallepidermal cells, large gland cells, and elongated trichogen cells. As a result of Mallory's triple straining , the epicuticle , the papila-like structure apart form the tubules inside which are gathered at the base and connected with a middle layer cell through a canal in the cuticle, and the peripheral of the urticating spcicule are yellow. However, the inside of the spicule , the tubules within the papilla-like structure, the canal in the cuticle , nuclei in the pidermal cells and the thin exocuticle are red although the thich endocuticle is blue. Particularly , the large nuclei in the middle layer cells are bright red, the cytoplasms of which are little and stained red, too, and the inside of the spicules apt to be stained red when they are broken. The contents therefore seem to be continuous between the spicules and the large cells. Presumably , the large cell at the middle layer is not te tormogen cell which Tsutsumi (1958) has described , but the gland cell which secretes the poison-substance into spicules as Pawlowsky and Stein 91927) and Tonkes (1933) pointed out. Whether the pisonous substance is secreted from the gland cell into the cytoplasmic processes of the trichogen cells which stick large middle layer cells during the formation of the new spicule as Tsutsumi (1958) has observed, or the gland cell makes a new connection with the spicule after the spicule is formed is not clear.

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사용후핵연료 차세대관리 종합공정 실증시설 (Hot Cell Facility for Demonstration of Advanced Spent Fuel Conditioning Process)

  • 정원명;구정회;조일제;국동학;이은표;백상열;이규일;유길성;박성원
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2003년도 가을 학술논문집
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    • pp.331-336
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    • 2003
  • 국내 경수로형 사용후핵연료의 효율적인 관리를 위하여 현재 건식처리공정으로 개발 중에 있는 차세대관리 종합공정의 실증시험이 계획되어 있다. 실증시험의 수행을 위해서는 기밀성이 유지되는 ${\alpha}{\gamma}$ type 핫셀시설과 시설의 안전성 확보가 필수적이다. 핫셀시설 확보에 필요한 재원을 최소화하기 위하여 기존 ${\beta}{\gamma}$ type 핫셀을 개조하여 활용하기로 하였으며, 차세대관리 종합공정의 특성을 고려하여 실증시설의 보수적 안전성 확보와 핫셀 내 효율적인 공정운전을 위한 분야별 설계요건을 확립하였다. 또한 이를 기준으로 실증공정의 공정조건과 상세한 작업흐름을 분석하여 핫셀 및 부대설비와 공정기기들의 구성과 배치론 최적화하였으며, 실증공정 및 핫셀 개조를 위한 기본 설계와 상세설계, 안전성분석과 환경영향평가를 완료하였다.

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360 Wh급 퍼스널 모빌리티용 리튬이온 배터리 팩의 열전달 특성에 관한 연구 (Numerical Study on the Heat Transfer Characteristics of 360 Wh Li-ion Battery Pack for Personal Mobility)

  • 김대완;서재형;김학민;이무연
    • 한국산학기술학회논문지
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    • 제18권8호
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    • pp.1-7
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    • 2017
  • 본 논문은 퍼스널 모빌리티에 사용되는 360 Wh급 리튬이온 배터리 팩의 성능 및 안정성 확보를 위하여 리튬이온 배터리 팩의 열전달 특성에 관하여 상용수치해석 프로그램인 ANSYS v17.0의 CFX를 이용하여 수치적으로 연구하였다. 이를 위하여 퍼스널 모빌리티에 사용되는 360 Wh급 리튬이온 배터리 팩의 배터리 셀 배열을 4가지 경우로 변경하고, 배터리 셀 홀더에 사용되는 재질과 배터리 팩 케이스에 사용되는 재질을 각각 Polypropylene, Aluminium, Magnesium alloy로 변경하였다. 그 결과 배터리 평균 온도는 배터리 셀 배열이 Model 2 일 때 가장 낮게 예측되었으며, 배터리 셀 홀더와 배터리 팩 케이스 재질 변경에 따른 배터리 평균 온도는 대부분의 경우 Aluminium 일 때 가장 낮게 예측되었다. 퍼스널 모빌리티에 사용되는 360 Wh급 리튬이온 배터리 팩의 열전달 성능은 배터리 셀 배열과 배터리 팩 케이스 재질에 많은 영향을 받았으며, 배터리 셀 배열 Model 2와 배터리 팩 케이스 재질이 Aluminium 일 때 가장 높았다.

실새삼(Cuscuta australis R. Brown) 흡기세포(吸器細胞)의 미세구조(微細構造) (Ultrastructure of Haustorial Cells of Cuscuta australis R. Brown)

  • 이재두;이규배
    • Applied Microscopy
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    • 제16권2호
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    • pp.49-60
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    • 1986
  • Ultrastructures of the large and elongated cells (idioblasts) in the haustorium of a parasitic angiosperm, Cuscuta australis R. Brown growing on the host plant, Trifolium repens L. were investigated by the electron microscopy. The idioblasts were characterized by the presence of a large nucleus, small vacuoles, and dense cytoplasm including a number of various cell organelles such as ribosome, rough endoplasmic reticulum(r-ER), mitochondrion, dictyosome, proplastid, multilamellar structure(MLS), microfilament bundle(MFB), and cytosegresome. Therefore, it is suggested that the idioblasts are metabolical1y very active. Particularly, MLS, MFB, and cytosegresome observed in this study did not appear in the haustorial cells of the other parasitic angiosperms. MLS was transformed into vacuole and also incorporated with cell wall. MFB composed of microfilaments, about each 7.5 nm in diameter, was observed in nucleus and also cytoplasm. Some types of MFB were distinguished on the basis of arrangement of microfilaments. A part of cytoplasm sequestered by stacked cisternae of smooth ER(s-ER), cytosegresome, was altered into a vacuole which was formed by digestion of the sequestered cytoplasm and of cisternae of s-ER. Cell organelles such as MLS, MFB, and cytosegresome were discussed in relation to the metabolic control of the idioblasts.

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타셈 싱(Tarsem Singh) 영화의상에 표현된 매직리얼리즘의 표현특성 - 더 셀(The Cell)과 더 폴(The Fall) 영화를 중심으로 - (The Characteristics of Magic Realism Expressed in the Costume of Tarsem Singh Movies - Focusing on "The Cell" and "The Fall" -)

  • 양수현;이연희
    • 복식
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    • 제65권1호
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    • pp.1-14
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    • 2015
  • Magic realism, which originated in the culture of Central and South America, creates a fantastic fictional word by linking unrelated incidents using magical. The purpose of this study was to analyze Tarsem Singh's design characteristics that are based on magic realism in his movies, "The Cell" and "The Fall", and to highlight the artistic values appearing in the films. The research was conducted by observing the characteristics and concept of magic realism based on literature and preceding research, and discovering how Singh expressed these creatively and experimentally within the costumes in his films. The results of the study were as follows: Firstly, magical, legendary and symbolic characteristics appear within the fantasy of magical realism, and common techniques within film costuming include repetition of similar objects, solid silhouettes within scenes, and various decorative materials used for fantastic expression. Secondly, regarding ideality, the destruction of previous ideas and recreation of the present were found with materials and details used in film costuming to destroy previous ideas. Expressions of character through external decoration and depiction of living things as not living were also found. Thirdly, reiteration showed the coexistence of history and legend, reality and fantastic elements, and arrangement of opposing elements.

비정렬격자계를 사용하는 3차원 유동해석코드 개발 (I) - 수치해석방법 - (Development of 3-D Flow Analysis Code Using Unstructured Grid System (I) - Numerical Method -)

  • 김종태;명현국
    • 대한기계학회논문집B
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    • 제29권9호
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    • pp.1049-1056
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    • 2005
  • A conservative pressure-based finite-volume numerical method has been developed for computing flow and heat transfer by using an unstructured grid system. The method admits arbitrary convex polyhedra. Care is taken in the discretization and solution procedures to avoid formulations that are cell-shape-specific. A collocated variable arrangement formulation is developed, i.e. all dependent variables such as pressure and velocity are stored at cell centers. Gradients required for the evaluation of diffusion fluxes and for second-order-accurate convective operators are found by a novel second-order accurate spatial discretization. Momentum interpolation is used to prevent pressure checkerboarding and the SIMPLE algorithm is used for pressure-velocity coupling. The resulting set of coupled nonlinear algebraic equations is solved by employing a segregated approach, leading to a decoupled set of linear algebraic equations fer each dependent variable, with a sparse diagonally dominant coefficient matrix. These equations are solved by an iterative preconditioned conjugate gradient solver which retains the sparsity of the coefficient matrix, thus achieving a very efficient use of computer resources.

목재세포벽(木材細胞壁)의 미세구조(微細構造)에 관한 연구(硏究) - Compression wood의 나선비후(螺旋肥厚)의 구조(構造) - (Ultrastructure of Wood Cell Wall Tracheids - The Structure of Spiral Thickenings in Compression Wood -)

  • 이원용
    • Journal of the Korean Wood Science and Technology
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    • 제9권1호
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    • pp.1-12
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    • 1981
  • The structure of spiral thickenings, particulary the appearance, arrangement and orientation of thickenings in compression wood of Torreya nucifera, were studied in detail by light and polarizing microscope, scanning and transmission electron microscope. The results obtained are as follows: (1) Using the inclined sections at an angle of 45 degrees to the fiber axis, it seems that we can not only observe the more accurate transverse view of the thickenings but also investigate the formation of their thickenings. (2) Generally 2-4 pieces of thickenings are projected to the cell lumen as nipple-like appearance in transverse section and are as frequent, well developed, forming pair and have the rope-like appearance in radial surface. (3) The secondary wall of early wood is composed of 3 layers (S1, S2, S3) and orientation of thickening appears S helix but that of late wood is of 2 layers (S1, S2) and that orientation shows Z helix. Above two regions are demaracted at several tracheid cells from the growth ring boundary. (4) Orientation of thickening seems to be a element showing the characteristics of compression wood in Torreya nucifera. (5) It believes that the thickenings of compression wood are integral part of the S3 in early wood tracheids and of the S2 in late wood and have the same orientations as the inner-most microfibrils in these layers. (6) Thickening and cavities seem to be not formed together in a secondary cell wall of same tracheids.

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Power Sharing and Cost Optimization of Hybrid Renewable Energy System for Academic Research Building

  • Singh, Anand;Baredar, Prashant
    • Journal of Electrical Engineering and Technology
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    • 제12권4호
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    • pp.1511-1518
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    • 2017
  • Renewable energy hybrid systems look into the process of choosing the finest arrangement of components and their sizing with suitable operation approach to deliver effective, consistent and cost effective energy source. This paper presents hybrid renewable energy system (HRES) solar photovoltaic, downdraft biomass gasifier, and fuel cell based generation system. HRES electrical power to supply the electrical load demand of academic research building sited in $23^{\circ}12^{\prime}N$ latitude and $77^{\circ}24^{\prime}E$ longitude, India. Fuzzy logic programming discover the most effective capital and replacement value on components of HRES. The cause regarding fuzzy logic rule usage on HOMER pro (Hybrid optimization model for multiple energy resources) software program finds the optimum performance of HRES. HRES is designed as well as simulated to average energy demand 56.52 kWh/day with a peak energy demand 4.4 kW. The results shows the fuel cell and battery bank are the most significant modules of the HRES to meet load demand at late night and early morning hours. The total power generation of HRES is 23,794 kWh/year to the supply of the load demand is 20,631 kWh/year with 0% capacity shortage.