• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.143-150
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• 2008

In this study, we examined the effect of hydroxyl radical generated by $\gamma$-ray and UV irradiation on shrinkage of vitreous body. Change in gel ratio of vitreous body and change in the properties of its components (collagen, sodium hyaluronate) were analyzed. By comparing these results, the amount of hydroxyl radical, which induces the considerable shrinkage of vitreous body, was evaluated from theoretical calculation based on experimental condition and some reported kinetic parameters. It was concluded that the integrated amount of hydroxyl radical required to liquefy half of the vitreous body (Vitreous body gel ratio = 50%) was estimated as $140\;{\mu}molg^{-1}$ from $\gamma$-ray irradiation experiment. Also, from UV irradiation experiment result, it was confirmed that the effect of hydroxyl radical is larger than that of other reactive species. The causes of shrinkage of vitreous body are supposed as follows, 1) decrease in viscosity by cleavage of glycoside bond in sodium hyaluronate, 2) leaching of collagen from vitreous body and 3) leaching of crosslinked products and scission products of collagen.

• Proceedings of the Zoological Society Korea Conference
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• 2001.04a
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• pp.54-54
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• 2001

Nephila clavata ; cornea ; lens ; vitreous body ; retina ; and rhabdome ; tepeta

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.49-56
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• 2001

Ocular lesions induced in 40 specific-pathogen-free Marek's disease (MD) resistant chicks by inoculation at 1 day of age with very virulent strain of Marek's disease virus (WV) were pathologically examined. Grossly,24/40 (60%) chicks had white gel-like materials in the vitreous body, whereas thickening and discoloration of iris (gray eye) were not observed. Microscopically, characteristic ocular MD lesions were observed in choroid (27/40), ciliary (30/40) and iris (23/40) in which small focal inflammatory to diffuse neoplastic Iymphoid cells were infiltrated. Five out of 40 MDV-inoculated birds revealed necrotizing Iymphomas in choroid. These lesions consisted of necrotic and degenerating Iymphoblasts accompanied by intranuclear inclusion body. There was retinal atrophy and necrosis with inclusion body detected in necrotic ganglion, inner or outer nuclear and infiltrated Iymphoblast cells. Conjunctiva showed lymphoid cell infiltration in 29/40 chicks inoculated with MDV, Vitreous body exhibited mild to severe exudation of eosinophilic proteinaceous material in 24/40 chicks. These lesions were associated with Iymphoid cell infutration, edema and fibrosis of choroid. Pecten (7/40) and optic nerve (13/40) were infiltrated usually mildly with Iymphoid cells. From these results, very virulent strain, Md/5 of MDV caused high incidence of ocular lesions in MD resistant chicks. In addition, Md/5 induced exudation of proteinaceous material into the vitreous body and fibrosis of choroid. Necrotizing ocular Iymphoma lesions in choroid is the first report in the MD literature.

• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.239-246
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• 2013

Principle of foamed glass manufacturing process first starts with putting vitreous material powder into a mold. After the foaming calcination, foamed body should be annealed after separation from the mold. For this reason, existing manufacturing process could not be a continuous type process. In this study, in order to develop a continuous production process of foamed glass, the possibility of new foam glass manufacturing process was investigated by foaming calcination of the compact body obtained from compression-molding of vitreous raw materials in stead of using a mold. Through the experimental results of the foaming calcination of the compact body with adding various foaming agents such as $Na_2CO_3$, $CaCO_3$ and petroleum coke, into hydrated soda-lime vitreous raw materials, it was shown that developing a continuous process without using any molds for manufacturing foamed glass would be possible.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.32-35
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• 1962

Six frogs (Rana nigromaculata 25∼40 gm) were adapted to light for 2 hours. Then 0.02 ml of 3% nicotinamide and 0.02 ml of 0.6% folic acid were injected into the vitreous body of the right eye-ball, and 0.02 ml normal saline solution into the vitreous body of the left eye-ball respectively. After dark adaptation for an hour-their heads were cut off under a dim red light (650 $m{\mu}$). The retinae were removed from the left eye-ball for the control group and from the right for the test group respectively. Then rhodopsin was extracted from the retinae with 3 ml of 2% digitonin solution(pH = 7.0) for 17 hours at 0$^{\circ}C$ in the dark. The optical densities before and after the illumination of the extract were measured and compared with those of the control group. The results are as follows: 1) The group which had been injected with 0.02 ml of 3% nicotinamide solution had the promotive action on tile regeneration of rhodopsin in comparison with the control group. 2) The group which had been injected with 0.02 ml of 0.6% folic acid solution had the controlling action on the regeneration of rhodopsin in comparison with the control group.

• Applied Microscopy
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• v.28 no.4
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• pp.477-490
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• 1998

Most spiders have four pairs of simple eyes. A few families of the spider have their developed eyes to an extent visual cues make up a significant of information to response from the external stimuli. Most spiders respond to the external stimuli around them. Specially, they are very sensitive to vibrations from the air, the ground, their webs, or even the surface of water. The present study was undertaken to examine the evolutionary development and function of eye with the observation of visual ultrastructure of Atypus coreanus Kim, 1985 using the electron microscopy. They have weak mobility, limited territory and low developed eyes. Atypus coreanus was collected from Mt. Ungil, Namyangju-gun, Kyonggi province. The fine structure of these eyes was examined by electron microscopy, and prepard by teasing method for scanning electron microscopic observation. As a result, the eyes of Atypus coreanus was composed of cornea, lens, vitreous body, retina, and rhabdome.

• Journal of the Korean Ceramic Society
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• v.23 no.5
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• pp.47-54
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• 1986

The structures of crystalline vitreous and liquid $SiO_2$ were Monte carlo simulated employing the potential energy function comprising Lennard-Jones 2-body and Axilrod-Teller 3-body potentials. Although the Si-O-Si angular distribution functions obtained in the simulation appear to be higher than the experimental results the other simulation results including SiO, O-O and Si-Si radial distribution functions and O-Si-O anglular distribution functions agree well with experimental data within acceptable limits. Themost important outcome in this study is that various $SiO_2$forms were successfully reproduced with the same potential energy function.

• Applied Microscopy
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• v.24 no.3
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• pp.1-9
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• 1994

Pardosa astrigera possessed eight eyes arranged in three rows on the frontal carapace. A pair of small anterior lateral eyes (ALE) flanked each side by an anterior median eyes (AME) lay along the anterior margin that was situated on the anterior row of clypeus. The anterior lateral eye was composed of cornea, vitreous body, and retina. Cornea was made up mainly of exocuticle lining the cuticle. Lens in anterior lateral eye was biconvex type which bulged into the cavity of the eyecup. Outer and inner central region of lens were approximately spherical with radius of curvature $5.6{\mu}m$ and $12.5{\mu}m$, respectly. Vitreous body formed a layer between the cuticular lens and retina. They formed biconcave shape. Retina of the anterior lateral eyes was composed of three types of cells: visual cells, glia cells, and pigment cells. The visual cells were unipolar neuron, as were the receptor of the posterior lateral eye. But cell body was unique to the anterior lateral eyes. They were giant cell, relatively a few in number, and under the layer of vitreous bodies. Each visual cell healed rhabdomeres for a short stretch beneath the cell body. Rhabdomes were irregulary pattern in retina and electron dense pigment granules scattered between the rhabdomes. Glia cell situated at the cell body of visual cell and glia cell process reached to rhabdomere portion. Below the rhabdome, tapetum were about $30{\mu}m$ distance from lens, which composed of 4-5 layers. It was about $25{\mu}m$ length that intermediate segment of distal portion of visual cell. Electron dense pigment granules between the intermediate segment were observed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.658-664
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• 1997

The effect of metal oxides($K_2O, MgO, CaO,Al_2O_3$, and $TiO_2$) on the kinds of pure $SiO_2$ phase, and $SiO_2$ phases in the composition of vitreous porcelain body was investigated. Also, the effect of the ratio $SiO_2$ to $Al_2O_3$ in the composition of porcelain body with stabilized of cristobalite phase was investigated. In the case of the addition of $K_2O, MgO, CaO, Al_2O_3$, and $TiO_2$ to pure $SiO_2$, the major phase was $\alpha$-cristobalite, $\alpha$-cristobalite, $\alpha$-quartz, $\alpha$-quartz and amorphous, respectively. As the ratio of $SiO_2$ to $Al_2O_3$ in the composition of porcelain body was decreased, the stabilization of cristobalite phase was promoted and only the critical value of $SiO_2/Al_2O_3$ ratio that stabilizing the cristobalite phase in it was 68.10/22.75. The addition of $K_2$O, MgO, CaO,Al_2O_3$, and $TiO_2$ to the composition of porcelain body stabilized already did not affect on the formation of $\alpha$-cristobalite phase which degraded the thermal properties of porcelain body, and suppressed the formation of a, $\beta$-cristobalite.

• Applied Microscopy
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• v.28 no.3
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• pp.363-377
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• 1998

After the investigation on the eye of Incilaria fruhstorieri with light and electron microscopes, the following results were obtained. The eye of Incilaria fruhstorferi comprises cornea, lens, vitreous body, retina, and optic nerve inward from the outside. Cornea is composed of squamous, cuboid, columnar and irregular cells, which appear to be light due to their low electron density. In their cytoplasms, glycogen granules, multivesicular body, and nucleus were observed. Vitreous body, located behind non-cellular transparent lens, is filled with long and short microvilli protruding from the retinal epithelia. Retinal epithelium, the organ to perceive objects, is divided into four parts; microvillar layer pigment layer, nuclear layer, and neutrophils layer, from the apical portion. Microvillar layer consists of the type-I photoreceptor cells and pigmented granule cells. In the apical portion of their cytoplasms, long microvilli (length, $19{\mu}m$) , short microvilli (length, $8{\mu}m$), and rolled microvilli grow thick in the irregular and mixed forms. Photoreceptor cells are classified into type-I and type-II, according to their structures. The type-I cell has the apical portion rising roundly like a fan and the lower part which looks like the helve of a fan. In the cytoplasm of the apical portion, there are clear vesicles, cored vesicles, ovoid mitochondria, and microfilaments, and in the cytoplasm of the lower part, photic vesicles with their diameters about 60nm aggregate densely. The type-II photoreceptor cell, located at the lower end of the type-I cells, has a very large ovoid nucleus 3nd no microvilli. In the cytoplasm of the type-II cell, the photic vesicles with sizes 60nm aggregate more densely than in the cytoplasm of the type-I cell. Pigmented cells are classified into type-A and type-B, according to their structures. The type-A is identified to be a large cell containing round granules (diameter, $0.5{\mu}m$) of very high electron density, while the type-B is identified as a small cell where the irregular granules (diameter, $0.6{\mu}m$) of a little lower electron density amalgamate. Nuclear layer ranges from the bottom of pigment layer to the top of the capsule, and contains three kinds of nuclei (nuclei of the type-II photoreceptor cell, pigmented granule cell, and accessory neuron). The capsules covering the outmost part of the eyeball are composed of collagenous fiber and three longitudinal muscle layers (the thickness of each longitudinal muscle layer, $0.4{\mu}m$) and thick circular muscle layer (thickness, $0.3{\mu}m$). Around the capsules, there is a neurophile layer consisting of neurons and nerve fibers. Each neuron has a relatively large ovoid nucleus for its cytoplasm, and in the karyosome, large lumps of keterochromatin form a wheel nucleus.