• Applied Microscopy
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• v.26 no.4
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• pp.431-446
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• 1996

This experiment was performed to study the ultrastructural changes of the juxtaglomerular cell of mice following subcutaneous injection of heavy metallic agents. Male mice were divided into normal and experimental groups. The mice were subcutaneouly injected with $HgCl_2$ (2mg, 5mg or 10 mg/Kg/BW) or with $K_{2}Cr_{2}O_7$(5 mg, 10 mg or 20 mg/Kg/BW). Mice were sacrificed on 6 hours, 3 days and 14 days after the injection. Kidneys were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture. The sections were cut on a LKB-V ultratome, and ultrathin sections stained with uranyl acetate and lead citrate were observed with JEM 100CX II electron microscope. The results were as follow: 1. Juxtaglomerular cell of the experimental groups showed some alterations, especially in the structures of protein synthesis including dilations and degradations of granular endoplasmic reticula, atrophy of Golgi complex, and numerous free ribosomes in the cytoplasm. 2. Juxtaglomerular cells treated groups showed a number of vacuoles, protogranules and some myelin figures in the cytoplasm, especially in the earlier groups. 3. Juxtaglomerular cells of treated groups, contained a large number of secretory granules showing variable electron densities and pleomorphism in later groups (2 weeks). From the above results, it was concluded that, the mercuric chloride or potassium bichromate induces acute renin release from juxtaglomerular cells of the mice, but many juxtaglomerular cells may secrete prematured secretory granules, or the synthetic system of the cell can not perform normal function.

• Applied Microscopy
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• v.2 no.1
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• pp.17-31
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• 1972

Light and electron microscopic studies were made to investigate the morphological changes in growing galls on the leaf of Lycium chinense MILL caused by Eriophyes kuko Kishda. The results are summarized as follows: 1. Light microscopy At the early stage of the invasion of E. kuko on the back side of the young leaf of L. chinense, the.epidermal cells become hypertrophic and develope a gall. As the gall grows, the cells of both palisade and spongy-layers become hypertrophic and these tissues are hard to be distinguished because of their irregular outgrowth. As the gall grows, the nuclei of the gall also become hypertrophic and larger than these of normal cells. 2. Electron microscopy Under electron microscopy the mitochondria, the golgi apparatus and the plastids of the advanced galls are degenerated and disintergrated and the cell walls become thicker than normal ones. The characteristic star bodies and the ring-form structures are found in the mature gall cells.

• Structural Engineering and Mechanics
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• v.41 no.4
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• pp.495-508
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• 2012

The strength theory of concrete is significant to structure design and nonlinear finite element analysis of concrete structures because concrete utilized in engineering is usually subject to the action of multi-axial stress. Experimental results have revealed that lightweight aggregate (LWA) concrete exhibits plastic flow plateau under high compressive stress and most of the lightweight aggregates are crushed at this stage. For the purpose of safety, therefore, in the practical application the strength of LWA concrete at the plastic flow plateau stage should be regarded as the ultimate strength under multi-axial compressive stress state. With consideration of the strength criterion, the ultimate strength surface of LWA concrete under multi-axial stress intersects with the hydrostatic stress axis at two different points, which is completely different from that of the normal weight concrete as that the ultimate strength surface is open-ended. As a result, the strength criteria aimed at normal weight concrete do not fit LWA concrete. In the present paper, a multi-axial strength criterion for LWA concrete is proposed based on the Unified Twin-Shear Strength (UTSS) theory developed by Prof Yu (Yu et al. 1992), which takes into account the above strength characteristics of LWA under high compressive stress level. In this strength criterion model, the tensile and compressive meridians as well as the ultimate strength envelopes in deviatoric plane under different hydrostatic stress are established just in terms of a few characteristic stress states, i.e., the uniaxial tensile strength $f_t$, the uniaxial compressive strength $f_c$, and the equibiaxial compressive $f_{bc}$. The developed model was confirmed to agree well with experimental data under different stress ratios of LWA concrete.

• Journal of the Optical Society of Korea
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• v.19 no.6
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• pp.566-574
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• 2015

We report for the first time highly efficient trans-reflective color filters capable of demonstrating coloration in both transmission and reflection modes by taking advantage of a multilayer stack consisting of MgF₂ and TiO₂ used respectively as the low and high index materials. In order to enable such trans-reflective performance, securing an optimal stop band assuming an appropriate bandwidth within the visible regime is pivotal, which was realized by tailoring the thicknesses and the numbers of TiO₂-MgF₂ bi-layers. Three devices were designed through rigorous simulations and developed via e-beam evaporation to demonstrate vivid blue, green, and red colors in the reflection mode, and yellow, magenta, and cyan colors in the transmission mode, featuring an enhanced efficiency exceeding 90% under normal incidence. The color performance of the filters was examined by referring to the chromaticity coordinates of the transmission and reflection spectra, alongside photographed color images. The dependence of the performance on the angle of incidence was explored with respect to incident polarization, indicating that a transmission surpassing 60% could be stably maintained up to an angle of 75°. Polarization independent transfer characteristics were especially achieved for the normal incidence. The proposed devices may be readily extended to other spectral regimes by adjusting the thicknesses of the films.

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.21-27
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• 1978

The growing behavior of Candida albicans in various concentration of glucose and corticosteroid media was studied with the method of modified hanging slide culture. The strains of Candida albicans used in this study were obtained from vaginal swab from outpatients and were isolated from cultured colonies on Sabouraud's glucose agar media. To detect the budding rate of blastospore, the diluted suspension of Candida albicans in normal saline were inoculated into various concentration of glucose (Gl, G2, G3, G4), corticosteroid (S1, S2, S3, S4) and corticosteroid with 10% pepton broth (D1, D2, D3, D4) respectively and cultured at room temperature $(22{\sim}25^{\circ}C)$. The number of budding of blastospore were counted under the high power field of light microscope (400X) at specific time interval, e.g, 1, 2, 3, 6, 9, 12, 18, and 24 hours after inoculation. The results are as following: 1. The most effective budding rate was seen in G4 media (1.25% glucose) in 18 hours aft inoculation (89%). 2. The budding rate in Sabouraud's glucose broth with various concentration of dexamethasone added, was not significantly different from that of simple Sabouraud's glucose broth within 18 hours after inoculation, but there was statistically. significant difference in two budding rate at 24 hours observation. 3. The budding rate in 10% pepton broth media with various concentration of dexamethasone was almost same budding rate in control group, which is normal saline and 10% pepton broth, except on 2 and 24 hours results.

• Korean Journal of Veterinary Research
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• v.25 no.2
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• pp.133-144
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• 1985

The changes of acid-base status in vitro of the venous blood for 24 hours in ten Korean native goat were investigated. The acid-base parameters were measured within ten minutes after collection of the blood, and every hour during the first six hours and finally after twenty four hours of storage. Blood samples were stored at two different temperatures ($0-4^{\circ}C$ and $21-24^{\circ}C$). Twelve goats were induced acute acid-base disturbances by intravenous infusion of either hydrochloric acid or sodium bicarbonate and inhalated with $CO_2$ gas mixture (20% $CO_2$, 80% $O_2$) or hyperventilation were performed by means of respirator. The results were as follows; 1. Blood samples could be stored during the first two hours in ice water ($0-4^{\circ}C$) and one hour at room temperature without significant changes in pH. The magnitudes of changes were similar to those of cow, and lower than those of men and dogs. 2. The mean values of acid-base parameters in normal goat were arterial pH, 7.40; $P_{CO_2}$, 35.4mmHg; $HCO_3{^-}$, 21.8mEq/L. 3. Both the base excess and the bicarbonate showed high correlation (r=0.99) during the metabolic disturbance and were represented as $B.E.=1.38\;HCO^-{_3}-29.7$. 4. The slope of blood buffer curve obtained from the in vivo experiment was 16.3mEq/L/pH. 5. The magnitudes of changes in hydrogen ion concentration per unit change of $P_{CO_2}$ were 0.8nM/mmHg in hypercapnia and 1.0nM/mmHg in hypocapnia. 6. The ranges of acid-base parameters in normal goat urine were pH, 6.0-8.1; $P_{CO_2}$, 42-61mmHg; $HCO_3{^-}$, 2-110mEq/L. The concentration of potassium was higher (60-200mEq/L), and that of sodium was lower (8-70mEq/L) than those of human urine.

• Korean Journal of Acupuncture
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• v.19 no.1
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• pp.35-45
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• 2002

Acupuncture and herbal medicine have been used to prevent and treat the cerebrovascular accident, such as a stroke, and many studies of acupuncture and moxibustion concerning to the stroke have been undertaken in the human and various animals. However, it was not published the protective effect of the electroacupuncture (EA) of Huan-do (GB30) on the transient forebrain ischemia injury. The neuroprotective effects of EA (2 ms, 10 Hz, and 1 - 2 mA) of GB30 on the transient forebrain ischemia injury was investigated by western blot of nNOS and hematoxylin and eosin stain in Sprague-Dawley rats. The transient forebrain ischemia injury resulted in increased expression of nNOS in the brain for 6 hrs after ischemia, and EA decreased significantly expression of nNOS protein in brain increased by transient forebrain ischemia injury. The survived neuronal cell stained with hematoxylin and eosin (H&E) decreased in the hippocampus by the 7 days after ischemia comparing with the normal. Comparing with the normal, the survived neurons seriously decreased cell in the hippocampus after the injury. However, the proportion of survived neurons was increased in EA treatment. These results suggest that EA of GB30 have neuroprotective effects on transient forebrain ischemia injury.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.293-299
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• 1991

To investigate the effect of cooking form of rice and barley on postprandial serum glucose and insulin response in normal subject, five test carbohydrates calculated to contain 50g of glucose were consumed. Oral ingestions were divided into 5 group, i. e. dextrose(control), ground white rice, ground barley, whole white rice, whole barley, Postprandial glucose and insulin responses were measured over 3hr and showed the following pattern. Dextrose and ground white rice elicited similar postprandial serum glucose and insulin responses whereas ground barley and whole white rice intemediate, whole barley gave the lowest responses in the test group. The ground form of rice and barley were significantly higher responses than the unground form of those as well as whole white rice were higher responses whole barley, The results suggested that the cooking form of rice and barley was an important determinant of the postprandial metabolic responses.

• Korean Journal of Community Nutrition
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• v.9 no.5
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• pp.555-565
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• 2004

The objective of this study was conducted to investigate growth and development status of infants fed soy-based formulas over 3 months. The height and weight were measured and Z-scores were calculated by using standard of the same age groups. Their mothers were interviewed using questionnaires including general and environmental characteristics, total food intakes, soy based formula intakes and Ewha infant development screening test. Main results were as follows: 1) Nutrient intake levels of subjects were similar to or more than the level of Korean Recommended Dietary Allowances except for intakes of vitamin E (79.89% RDA), and the average status of nutrient intakes of infants were fairly good. 2) Z-scores of height for age (HAZ) and Z-scores of weight for age (WAZ), Kaup index, WLI and Ewha Infant Developmental Screening Test score of subjects were in the normal growth range. 3) There were no significant differences among soy based formula intake percentile groups in HAZ, WAZ, Kaup index, WLI and Ewha Infant Developmental Screening Test score. 4) Total energy intake was positively correlated with HAZ (p < 0.00, WAZ (p <0.00, and WLI (p < 0.05) in infants less than 12 month. Also, soy based formula energy intake was positively correlated with HAZ (p < 0.05) in infants less than 12 month. However, energy and soy based formula intake levels of infants over 12 month were not significant among variables. Considering results of this study, infants fed soy-based formulas over 3 months showed normal growth and development status. Further studies are needed to evaluate longterm growth and development in infants fed soy based formulas.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.129-136
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• 2012

Compression splices are required for all compression members in almost all of the floors in high-rise buildings. Therefore, a clear understanding of the behavior of compression splices can provide a rational design of compression splices. Tests of compression splices with bearing only and bond only cases were conducted to investigate the component resistance characteristics of compression splices. Test results showed that the circumferential tensile stresses induced by bearing and bond overlapped at the end of the splice length deterred bond and bearing splices from developing target splicing strength when both normal bond and bearing splices were used. In particular, the bearing strength was more significantly reduced than the bond strength since the bearing relied on the limited area near the end of the splice length. However, the strength of the normal splice was always higher than the strength of the bond only or the bearing only case. Consequently, the study results showed that splice strength in compression cannot be improved by means of removing bond or bearing. In addition, the bond strength in bond only splices was nearly same as the bond strength in tension splices and the strength increase of compression splice is attributed to end bearing only characteristic.