• Applied Microscopy
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• v.26 no.4
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• pp.421-430
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• 1996

The endocrine cells in the midgut epithelium of the Japanese cockroach, Periplaneta japonica were observed by the light and electron microscopy. The midgut epithelium of the last instar larva and adult cockroach consisted of principal columnar cells, regenerative cells, and secretory granular cells. Midgut endocrine cells were positioned basally as a cone-shaped single cell in the epithelium or underneath the regenerative crypt cells. When midgut epithelium grows and the cell composing it transforms, between the endocrine cells and regenerative cells were made desmosome type junction and large vesicular shaped stretches of loose contact. The endocrine cells were characterized by a clear cytoplasm with abundant Golgi complex and numerous secretory granules. The secretory granules in the cell were spherical and electron dense with their diameter of $200{\sim}400nm$. The secretory granules have been observed as discharged by exocytosis on the basal and lateral side of the cell.

• Imaging Science in Dentistry
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• v.47 no.3
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• pp.209-213
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• 2017

Central giant cell lesions are rare, benign, osteolytic, pseudocystic, solitary, localized lesions that are common in the skeletal structure, but less so in the maxillofacial region. Furthermore, to perform panoramic radiography and cone-beam computed tomography, it is necessary to prepare patients properly and to position their heads carefully. However, this can be difficult in pediatric patients, who may be anxious. In this report, we describe the case of a central giant cell lesion of the mandible in a 2-year-old girl that was evaluated with multidetector computed tomography.

• Korea-Australia Rheology Journal
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• v.19 no.4
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• pp.227-232
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• 2007

The use of various shearing apparatuses to study the phase behavior of poly(styrene-b-isoprene) diblock copolymer micelles is described. A DMTA rheometer was modified so that one can apply oscillatory shear and obtain the scattering pattern along the shear gradient direction. A cone and plate shear cell was designed to access scattering along the shear vorticity direction, and both oscillatory and steady shear can be applied. The most popular way to employ steady shear on relatively low viscosity fluids is to use a Couette cell, because a high shear rate can be readily achieved without disturbing the sample by overflow. In this work, oscillatory shear was used to obtain a single crystal-like scattering pattern, and thereby to examine the mechanism of the thermotropic transition between face-centered cubic (fcc) and body-centered cubic (bcc) lattices. By applying the steady shear, the response of the fcc lattices to various shear rates is discussed.

• The Journal of Korean Physical Therapy
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• v.12 no.3
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• pp.415-432
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• 2000

In mammals. axotomy of peripheral nerve leads to a complex. These events include swelling of cell body, disappearance of Nissl substance. Proximal and distal axon undergoes a variable deriable degree of traumatic degeneration and wallerian degeneration, respectively. Nerve injury may result in cell death or regeneration. Molecular changes include proliferation of Schwann cells, upregulation of neurotropism, neural cell adhesion molecules and cytokine. Also growth cone plays an essential role in axon guidance through interaction of cytoskeleton. We review cellular and molecular events after nerve injury and describe nerve regeneration and associated proteins.

• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.218-223
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• 2017

Using both light and scanning electron microscopies, it was investigated on the visual cells as well as the eyes of Macropodus ocellatus (Pisces, Osphronemidae). This species had a circular lens and yellowish cornea. The eyes had $3.5{\pm}0.2mm$ which is $31.1{\pm}3.0%$ in a percentage of eye diameter relative to head length. The retina ($158.2{\pm}10.6{\mu}m$) was built of several layers, including the visual cell layer which consists of three types of cells: single cons ($27.8{\pm}1.6{\mu}m$) and equal double cone ($33.9{\pm}3.7{\mu}m$), and large rods ($57.3{\pm}1.3{\mu}m$). The visual cell layer then was classified into the correct pattern. All visual cells were clearly distinguished from two parts (inner and outer segments). The elongated rod cells were extend to the bottom of the retinal pigment epithelium. In scanning electron microscopy, the outer segment links to inner segment by so-called calyceal piles. The M. ocellatus single and double cones appearance form a flower-petal arrangement, which is a regular mosaic pattern that contains quadrilateral units by four double cones surrounding a single cone.

• Journal of Plant Biology
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• v.39 no.2
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• pp.137-144
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• 1996

Scanning electron microscope revealed several taxonomically useful characters in the perigynium and achene epidermis of sect. Siderosticatae (Carex siderosticta, C. ciliatomarginata and C. okamotoi). Mocroscopic characters such as perigynium shape, hair presence or absence, beak shape, nodule situation in perigynium, achene shape, cell wall and silica cone in achene were useful in Carex at the species levels. A key was presented on the basis of features obtained from the examinations.

• Korean Membrane Journal
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• v.5 no.1
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• pp.10-17
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• 2003

1,3,5-Sustitituted polyphenylene type dendrimers were synthesized. The dendrimer was heated in cone. H$_2$SO$_4$ at 120$^{\circ}C$. The reaction mixture was precipitated to ether after simple filtration to get para-sulfonated dendrimer as the chief product. To give mechanical properties to the sulfonated dendrimer, it was partially cross-linked with phenyl ether in the medium of P$_2$O$\sub$5/ and CH$_3$SO$_3$H.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.371-372
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• 2002

It is well known that red blood cells (RBCs) are suffered from chronic stresses in systemic circulation. The objective of this study is to clarify the effect of the aging of RBCs on rheological properties and hemolysis. Initially, RBCs age fractionation was performed by using a high-speed centrifugation (15[min] at 1500[G]), then young and aged RBCs were suspended in plasma to adjust the hematocrit level of 40[%]. After this pretreatment, the viscosity was measured by using a capillary type and a cone-plate type viscometers, respectively, and the hemolysis test was carried out by a seesaw type shaker. Results from these experiments showed that the viscosity of the aged RBCs measured by the capillary viscometer was increased by 10[%] as compared with that of the young RBCs. Under the condition of all shear zones, the viscosity of the aged RBCs was increased in case of using the cone-plate type viscometer. And the hemolytic level was increased twice as the aging. The data obtained in this study indicated that the ability of aggregation of RBCs was increased and the deformability of RBCs membrane got lower with the aging. Furthermore, it was exhibited that the fragility of RBCs ’ membrane was increased with the aging.

• Applied Microscopy
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• v.9 no.1
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• pp.1-11
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• 1979

Electron microscopic studies were carried out to investigate the fine structure of ommatidia of the compound eyes in Meimuna mongolica D. The crystalline cone appears round, and is composed of four double-membraned cone cells and surrounded by pigment cells having many pigment granules. The rhabdom is a closed type, and is composed of four rhabdomeres Its cross section reveals lamellated microvilli which are oriented in four different directions suggesting that these represent four photoreceptive sites. The microvilli, in a cross sectional view, are hexagonal in shape with a central axis inside. There are usually eight retinular cells arranged radially from the rhabdom, but in some retinular layers seven or nine retinular cells could be observed. The cytoplasm of each retinular cell is interconnected with that of microvilli of the rhabdomere, but the appearance of this interconnection varies depending on the number of retinular cells.'The retinlilar cells neighboring the microvilli seem to have well-developed perirhabdomal vacuoles and mitochondria as well as pigment granules surrounding these vacuoles.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.472-481
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• 2009

Cementation phenomenon has a huge influence on geotechnical stiffness and strength under low confining pressure. The goal of this study is to evaluate the characteristics of stiffness according to the depth. The piezo disk elements are installed at each layer of the cell for the detection of the compressional waves. The change of compressional wave velocity is classified by three stages. The compressional wave velocities are shown different according to the depth. The compressional wave velocity is especially influenced by cementation, effective stress, and coordinate number. Furthermore, the electrical conductivity and cone tip resistance are measured according to the depth. The electrical conductivity and the cone tip resistance show the similar trend with the compressional wave velocity. This study shows that the cementation by salt is affected by the depth on the granular materials.