• Title/Summary/Keyword: Inclusions

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A Survey of Plastid Crystals and Microtubules in Flowering Plants (꽃피는식물 색소체 내 결정구조와 미세소관의 발달양상 조사 연구)

  • Kim, In-Sun
    • Applied Microscopy
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    • v.39 no.2
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    • pp.73-80
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    • 2009
  • The plastid inclusion has long been known to exist in leaves of numerous plant species, especially in those of flowering plants. Among the inclusions, crystalline bodies are the most frequently distinguished structures of the foliar plastids, however, microtubules and phytoferritins are also reported occasionally. The crystalline inclusions vary in shape, and are located either in the stroma or within intrathylakoidal spaces, whereas microtubules and phytoferritins are more uniform in shape and are formed in the stroma. In crystalline structures, the composing elements exhibit a lattice pattern and/or paralleled tubules that are either bounded by membranes or exist without membrane enclosing. Other types of inclusions have not been shown to be enclosed by any membranous structures. According to the current survey, the plastid inclusion, with the exception of phytoferritins, has been shown to exhibit a crystalline or tubular pattern, and has been reported in more than 56 species of various families. Their occurrence is not restricted to any photosynthetic pathway, but is found to be randomly distributed among C-3, C-4 and CAM species, without phylogenetic relationships. The progress in plastid inclusion research reveals more information about the function and complexity, but the need for characterizing the 3-D structure of the crystalline inclusions also has been acknowledged in previous studies. A 3-D characterization would utilize tilting and tomography of serial sections with appropriate image processing that would provide valuable information on the sub-structures of the crystalline inclusions. In fact, recent studies performed on 3-D reconstruction of the plastid inclusions revealed important information about their comprising elements. In this article, the crystals and microtubules that have been reported in various types of plastids have been reviewed, with special consideration given to their possible sub-cellular function within the plastids.

An investigation into the effects of voids, inclusions and minor cracks on major crack propagation by using XFEM

  • Jiang, Shouyan;Du, Chengbin;Gu, Chongshi
    • Structural Engineering and Mechanics
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    • v.49 no.5
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    • pp.597-618
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    • 2014
  • For the structures containing multiple discontinuities (voids, inclusions, and cracks), the simulation technologies in the framework of extended finite element method (XFEM) are discussed in details. The level set method is used for representing the location of inner discontinuous interfaces so that the mesh does not need to align with these discontinuities. Several illustrations have been given to verify that the implemented XFEM program is effective. Then, the implemented XFEM program is used to investigate the effects of the voids, inclusions, and minor cracks on the path of major crack propagation. For a plate containing cracks and voids, two possibly crack path can be observed: i) the crack propagates into the void; ii) the crack initially curves towards the void, then, the crack reorients itself and propagates along its original orientation. For a plate with a soft inclusion, the final predicted crack paths tend to close with the inclusion, and an evident difference of crack paths can be observed with different inclusion material properties. However, for a plate with a hard inclusion, the paths tend to away from the inclusion, and a slightly difference of crack paths can only be seen with different inclusion material properties. For a plate with several minor cracks, the trend of crack paths can still be described as that the crack initially curves towards these minor cracks, and then, the crack reorients itself and propagates almost horizontally along its original orientation.

Calculation of Stress Intensity Factors Using the Mixed Volume and Boundary Integral Equation Method (혼합 체적-경계 적분방정식법을 이용한 응력확대계수 계산)

  • Lee, Jung-Ki;Lee, Hyeong-Min
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.7
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    • pp.1120-1131
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    • 2003
  • A recently developed numerical method based on a mixed volume and boundary integral equation method is applied to calculate the accurate stress intensity factors at the crack tips in unbounded isotropic solids in the presence of multiple anisotropic inclusions and cracks subject to external loads. Firstly, it should be noted that this newly developed numerical method does not require the Green's function for anisotropic inclusions to solve this class of problems since only Green's function for the unbounded isotropic matrix is involved in their formulation for the analysis. Secondly, this method takes full advantage of the capabilities developed in FEM and BIEM. In this paper, a detailed analysis of the stress intensity factors are carried out for an unbounded isotropic matrix containing an orthotropic cylindrical inclusion and a crack. The accuracy and effectiveness of the new method are examined through comparison with results obtained from analytical method and volume integral equation method. It is demonstrated that this new method is very accurate and effective for solving plane elastostatic problems in unbounded solids containing anisotropic inclusions and cracks.

Cytologic Features of Secretory Meningioma in Squash Preparation -A Case Report- (분비성 수막종의 입착도말 소견 -1예 보고-)

  • Kim, Se-Hoon;Lee, Kwang-Gil;Kim, Tai-Seung
    • The Korean Journal of Cytopathology
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    • v.15 no.1
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    • pp.52-55
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    • 2004
  • Secretory meningioma is a distinct subtype of meningioma. We describe the cytologic features of a secretory meningioma on squash preparations, in comparision with other cytologic mimickers. A 54-year-old woman presented with hearing loss, vertigo, tinnitus, and headache for seven years. A brain MRI study revealed a 4.5cm sized mass in the cerebellopontine angle, which showed homogenous signal intensity in T2-weighted image. The intraoperative squash smear showed some well-defined, thin rimmed intracytoplasmic inclusions, containing a finely granular eosinophilic core among less cohesive meningiomatous cells. Histologic sections revealed a meningothelial meningioma with scattered inclusions, with periodic acid-Schiff, carcinoembryonic antigen, and cytokeratin positivity. Identification of characteristic intracytoplasmic inclusions is helpful for diagnosing secretory meningiomas. On squash preparations, differential diagnoses included tumors with inclusions or cytoplasmic vacuolizations, such as metastatic mammary infiltrating ductal carcinoma, gastric adenocarcinoma, hepatocellular carcinoma, and clear cell ependymoma, oligodendroglioma, hemangioblastoma, chordoma, and other variants of meningiomas (clear cell, xanthomatous, microcytic, and chordoid variants). In addition, the possibilities of glioma with eosinophilic granular body, and metastatic tumors from mammary infiltrating ductal carcinoma, gastric adenocarcinoma, and hepatocellular carcinoma in meningioma should be considered.

Ultrastructural Aspects of the Mixed Infections with Turnip mosaic virus and Ribgrass mosaic virus in Oriental Cabbage

  • Kim, Jeong-Soo;Cho, Jeom-Deog;Park, Hong-Soo;Kim, Kyung-Soo
    • The Plant Pathology Journal
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    • v.17 no.4
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    • pp.201-204
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    • 2001
  • Ultrastructural observation was conducted for the cells of oriental cabbage, Brassica campestris ssp. pekinensis 'Chungawang', inoculated simultaneously with Turnip mosaic virus (TuMV-ACT2-4vq) and Ribgrass mosaic virus (RMV-Ca1dn2) which were known as major destructive viruses of oriental cabbage in Korea. In cells infected with RMV alone, the virus particles were located as bundle or scattering in cytosols and vacuoles, which were typical ultrastructures of tobamovirus. Vessels of xylem were compacted with RMV particles. The cells infected only with TuMV had the cluster of virus particles scarcely and the typical potyvirus inclusions of scrolls, pinwheels, tubes and laminated aggregates in cytosols. The TuMV particles were jammed lineally between tonoplasts. In double infection, the two unrelated viruses of TuMV-ACT2-4vq and RMV-CA1dn2 were located together in a cell, and typical properties of each virus were also observed. The potyvirus inclusions and the tobamovirus particles were mixed entirely in cytoplasm. The virus particles of RMV wre presented strikingly near and in the center of potyvirus inclusions. In vascular cells, the tobamovirus particles were located abundantly than those in single infection. The potyvirus inclusions were embedded in the cluster of RMV particles in phloem parenchyma cells and the vascular elements were degenerated severely.

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Phagocytic osteoclasts in the alveolar bone of diabetic rats with periodontitis

  • Bak, Eun-Jung;Kim, Ae Ri;Kim, Ji-Hye;Yoo, Yun-Jung
    • International Journal of Oral Biology
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    • v.45 no.3
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    • pp.92-98
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    • 2020
  • Periodontitis is a bacteria-induced inflammatory disease associated with alveolar bone loss. Osteoclast is a macrophage-lineage cell that exhibits phagocytic activity; however, osteoclast phagocytic activity has not been demonstrated under pathological conditions. Diabetes is a pathological condition that exacerbates alveolar bone loss via periodontitis; therefore, we examined phagocytic osteoclasts in diabetic rats that had periodontitis. The rats were divided into the control (C), periodontitis (P), and diabetes with periodontitis (DP) groups. Diabetes and periodontitis were induced by streptozotocin injection and ligature of the mandibular first molars, respectively. On days 3 and 20 after the ligature, the rats were sacrificed, and osteoclasts containing inclusions were quantified by tartrate-resistant acid phosphatase staining. On day 3, there were more osteoclasts containing inclusions in the DP group than in the C group. Among inclusions, osteocyte-like cells and dense bodies were more frequently observed in the DP group than in the C group. Cytoplasm-like structures were elevated more in the DP group than in the C and P groups. However, no differences were observed on day 20. Interestingly, some osteoclasts were in contact with the osteocytes within the exposed lacunae and contained several inclusions within a large vacuole. Thus, the elevation of phagocytic osteoclasts in rats with diabetes and periodontitis provides insight into the role of osteoclast phagocytic activity under pathological conditions.

Study of 2-Dimensional Model for the Thermal Expansion of Composite Materials (열팽창 계수의 2차원 해석 모델에 관한 연구)

  • Jeon, Hyeong-Jin;Yu, Sang-Won
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2005.11a
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    • pp.95-98
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    • 2005
  • This paper proposes the solutions predicting the coefficient of the thermal expansion changes of composites which include the fiber-like shaped ($a_1$ > ($a_2$ = ($a_3$) and the disk-like shaped (al = a2> a3) inclusions like two dimensional geometries, which has one aspect ratios, ${\alpha}$ = ($a_1$ /($a_3$). The analysis follows the procedure developed for elastic moduli by using the generalized approach of Eshelby’s equivalent tensor. The influences of the aspect ratios, on the effective coefficient of thermal expansion of composites containing aligned isotropic inclusions are examined. This model should be limited to analyze the composites with unidirectionally aligned inclusions and with complete binding to each other of both matrix and inclusions having homogeneous properties. The coefficient of thermal expansion of composites (${\theta}_{11}$,${\theta}_{22}$and ${\theta}_{33}$) are investigated. From material data of the composites with glass fiber in epoxy resin, the thermal expansions along the aspect ratio were obtained and similar to the Chow model. The longitudinal coefficients of thermal expansion ${\theta}_{11}$decrease, as the aspect ratios increase. However, the transverse coefficients of thermal expansion ${\theta}_{22}$increase or decrease, as the aspect ratios increase. And both of them decrease, as the concentration increases.

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Thermal Stress Intensity Factors for Rigid Inclusions of Cusp Crack Shape (커스프균열형 강체함유물의 열응력 세기계수에 관한 연구)

  • 이강용;최흥섭
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.3
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    • pp.497-504
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    • 1988
  • The steady state thermal stress intensity factors (TSIF's) are analyzed for hypocycloid, symmetric airfoil and symmetric lip type rigid inclusions embedded in infinite elastic solids, using Boganoff's complex variable approach in plane thermoplasticity. Two thermal conditions are considered, one with an uniform heat flow disturbed by an insulated rigid inclusion of cusp crack shape and the other with an uniform heat flow disturbed by a rigid inclusion of cusp crack shape with fixed boundary temperature. The tendencies of TSIF's for rigid inclusions of cusp crack shape are somewhat different from those of traction free cusp cracks. However, if k=-1, the non-dimensionalized TSIF's for rigid inclusions of cusp crack shape become those of traction free cusp cracks like the tendencies of the SIF's under mechanical loading conditions. The thermal stress and displacement components for a rigid circular inclusion of radius Ro are drived from the results of a hypocycloid crack type rigid inclusion.

Gas and Solute Compositions of Fluid Inclusions in Quartz from Some Base-metal ore Deposits, South Korea (남한의 주용 금속광상산 석영내의 유체포유물의 가스성분과 용존성분의 화학조성)

  • Kim, Gyu-Han;Jeong, Hae-Ran
    • Economic and Environmental Geology
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    • v.32 no.5
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    • pp.421-434
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    • 1999
  • Gas and chemical compositions of fluid inclusions in quartz some of Au-Ag, Pb-Zn-Cu and W-Mo mineral deposits in South Kores were analyzed to interpret the sources of ore fluid and the depositional condition of ore minerals in base-metal ore deposits. Fluid inclusions in quartz from the gold and silver mines are characterized by $CO_2$ rich fluids which have a wide range in $CH_4 \;and\; CO_2$ contents ($CH_4/CO_2$=0.001-0.225). The $CO_2$ rich but $CH_4$-poor nature of the fluid reflects the high fo2 condition during the mineral precipitation. The C2H6 is detected in hydrothermal quartz vines in metasedimentary rocks from the Jeonjoo-il, Youngbokari and Taechang mines. The $CH_4 /CO_2$ rations in W-Mo bearing quartz veins range from 0.005 to 0.214, which is similar with those in Au-Ag mines. However, skarn formation stage. Fluid inclusions, A relatively good correlation between Na and Cl contentrations reflects varible salinity in the fluid inclusion, it is suggested that the chemistry of promary magmatic hydrothermal fluids has changed during post-magmatic alteration and/or wall rock alteration processes. The content of gas compositions also depends on the kinds of country rocks, supporting above conclusion.

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