• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.4
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• pp.349-355
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• 2002

The ionic conductivity of cubic solid solutions in the systems of CaO-$ZrO_2$, $Y_2O_3-ZrO_2$ prepared by SHS was examined. The higher conductivity appears to be related to a lower activation energy rather than to the number of oxygen vacancies dictated by composition. Conductivity-temperature data was obtained at 1000 $^{\circ}C$ in atmosphere of low oxygen partial pressure (~$10^{-40}$ atm) for $Y_2O_3-ZrO_2$ cubic solid solutions. The data indicated that these materials could be reduced, and the decree of reduction would be related with the measuring electric field.

• Journal of Digestive Cancer Research
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• v.3 no.1
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• pp.5-10
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• 2015

With advances in the understanding of the biology and genetics of colorectal cancer (CRC), diagnostic biomarkers that may predict the existence or future presence of cancer or a hereditary condition, and prognostic and treatment biomarkers that may direct the approach to therapy have been developed. Biomarkers can be ascertained and assayed from any tissue that may demonstrate the diagnostic or prognostic value, including from blood cells, epithelial cells via buccal swab, fresh or archival cancer tissue, as well as from cells shed into fecal material. For CRC, current examples of biomarkers for screening and surveillance include germline testing for suspected hereditary CRC syndromes, and stool DNA tests for screening average at-risk patients. Molecular biomarkers for CRC that may alter patient care and treatment include the presence or absence of microsatellite instability, the presence or absence of mutant KRAS, BRAF or PIK3CA, and the level of expression of 15-PGDH in the colorectal mucosa. Molecularly targeted therapies and some general therapeutic approaches rely on biomarker information. Additional novel biomarkers are on the horizon that will undoubtedly further the approach to precision or individualized medicine.

• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.363-367
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• 1994

In an effort to investigate the role of calmodulin (CaM) as a modulating molecule in the signal transduction system in plant cells, we established methods for introduction of purified CaM into cultured soybean cells. CaM was purified from bovine testis, and was labelled with fluorescein isothiocyanate (FITC). Suspension -cultured cells were healed with saponin (0.1 mg/mL) to permeabilize the plasma membrane and coincubated with FITC-CaM complex. Saponin pretreatment was found to increase the fluorescence in the suspension cultured cells, indicating that the FITC-CaM complex could be incorporated into the cytoplasm. Optimal conditions for introducing FITC-CaM complex into protoplasts by electroporation were established with various electric pulses. With increasing field strength, the fluorescence in the protoplase was increased, while the viability of the protoplase decreased. FITC-CaM complex was successfully introduced into the protoplasts by electroporation and the amount of FITC-CaM complex in the protoplase was estimated.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.1-8
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• 1987

The distribution of the surface charges in two kinds of peats and their physico-chemical properties have a been studied by means of the potentiometric titration and by ion adsorption in different strength of electrolytes. The organic matter contents were 43.3% and 53.7% in Yeong Yang peat and Peong Tack peat, respectively. Their X-ray diffractograms showed that quartz was dominant in both peats, and illite, kaolinite, hydrated-halloysite and feldspars were contained in a trace. Total acidic group contents was 1.257me/g in Poeng Tack peat that was a little more than of Peong Yang heat were pKa values of Yeong Yang and Poeng Tack peat were 13.1 and 12.65, respectively. The titration curves at different ionic strength of electrolytes crossed at pH 3.9 and 4.4 in Yeong Yang peat, and pH 3.8 and 4.0 in Peong Tack peat. The pH ranges of suspensions when the net surfacecharge of the peats varied from positive to negative value were $pH\;4.55{\sim}5.20\;(NaCl)$ and $pH\;3.95{\sim}5.70\;(CaCl_2)$ in Yeong Fang peat, and $pH\;4.15{\sim}5.40\;(NaCl)$ and $pH\;3.80{\sim}4.15\;(CaCl_2)$ in Peong Tack peat. Therefore it is apparent that the zero point of charge of these peats was about pH 4.0.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.241-245
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• 2002

To effectively utilize ostrich egg shell as a calcium source, various conditions for preparation of calcium lactate from ashing powder (ashed for 15 min at 90$0^{\circ}C$) were evaluated. Optimal conditions involved treatment of ashing powder with 30 mL lactic acid solution at room temperature for 15 min with a CaO : lactic acid ratio (mol/mol) of 1:2. Calcium lactate contained 39.70% calcium comparable to that (40.98%) in ostrich egg shell. Solubility of calcium lactate, 97.7%, was considerably higher than those (0.58% and 3.43%, respectively) of ostrich egg shell and ashing powder, indicating that the former can be utilized more effectively as a calcium source than the two latter.

• The Journal of Korean Academy of Prosthodontics
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• v.24 no.1
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• pp.125-138
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• 1986

It is considered that etching solution or material itself of phosphoric ester cement will induce not a little pulpal irritation, if applied directly onto unsealed dentinal tubules. This study was designed to confirm above consideration by comparing two different conditions between $Ca(OH)_2$-based and non-$Ca(OH)_2$-based group. Posterior teeth of 15 male dogs were selected for this experiment. One experimental group was filled with cement after $Ca(OH)_2$-basing and enamel-etching, the other experimental group after enamel etching without $Ca(OH)_2$-basing. And both of two experimental groups were observed at 2 hours, 15 hours, 3 days, 1 week, 2 weeks, 4 weeks, and 6 weeks after filling. The findings reached to the following conclusions histologically. 1. In both groups, the damaged odontoblasts were atrophied and eventually disappeared. 2. In non-based group at early stage, odontoblasts were severely atrophied and defective areas were appeared between odontoblast cell layers. However, in based group, the odontoblasts were arranged slight irregularly. 3. In non-based group, a small number of undifferentiated cells below the odontoblast cell layers started to appear at 1 week after filling. However, in based group, the undifferentiated cells were appeared at 15 hours after filling. 4. In non-based group, formation of reparative dentin was not begun until late stage of experiment. However, in based group, formation of reparative dentin matrix was begun at 2 weeks after filling and very thickened reparative dentin was formed at 6 weeks after filling. 5. In odontoblast cell layers of both groups, dilated capillaries were observed. 6. Argyrophilic fibers were reticularly condensed in zone of Weil, and they were connected to the pulp tissue and dentin.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.336-341
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• 1995

Effect on alginate, pectin and Ca salts on textural properties of whole soybean gel(soygel) was investigated. The soygel was prepared by addition of sodium alginate, pectin and Ca salts into whole soy flour(300 mesh, WSF) suspension followed by through mixing. Addition of sodium alginate or pectin into WSF suspension significantly increased the hardness, adhesiveness and cohesiveness of the gel. The most uniform gel was obtained by $12{\sim}15%$ addition of sodium alginate or pectin, while their mixture rather decreased the textural properties. Sensory evaluation by ranking test for the gels showed that 12% sodium alginate and 0.125g $CaSO_4/g$ WSF produced the most desirable gel in terms of elasticity, uniformity, smoothness and total acceptability, followed by 12% sodium alginate and 0.12g Ca $gluconate-CaSO_4$(50 : 50). From the results, the optimal preparative conditions for soygel were suspension of WSF in 10 times of water(v/w), addition of 12% sodium alginate(w/w of WSF) and 12.5% $CaSO_4$ or Ca $gluconate-CaSO_4$(50 : 50) into WSF suspension followed by gel formation at $4^{\circ}C$.

• The Korean Journal of Physiology
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• v.17 no.2
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• pp.135-142
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• 1983

$PGE_2$ and $PGF_{2{\alpha}}$ are known to act similarly in a number of animal tissues. They both facilitate regression of corpus luteum(Poyser, 1972; Fuch et al, 1974; Coudert et at, 1974) and stimulate contraction of uterine muscle (Laudanski et al, 1977; Porter et al, 1979; Hollingsworth et al, 1980). It is, however, not known whether these two prostaglandins exert similar actions in osmotic fragility of erythrocytes (Rasmussen et al, 1975) and $PGF_{2{\alpha}}$ alters conformation of membrane proteins (Meyers aud Swislocki, 1974). The former effect may not be mediated through changes in c- AMP concentration in the cell, since the adenylate cyclase activity in human erythrocyte is extremely low (Rodan et al, 1976; Sutherland et al, 1962) and the latter effect implies that physical state (or fluidity) of the membrane is altered by $PGF_{2{\alpha}}$. The present study was undertaken to elucidate mechanisms of action of $PGE_2$ and $PGF_{2{\alpha}}$ on the human erythocyte membrane by examining their effects on osmotic fragility and $Ca^{++}$ binding to the membrane fragments. The results are summarized as follows: 1) $PGE_2$ and $PGF_{2{\alpha}}$ increased osmotic fragility at concentrations above $10^{11}\;M$, the effect being similar for both hormones. The concentration of NaCl for 100% hemolysis was $1/16{\sim}1/17\;M$ in the presence of $10^{11}\;M\;PGE_2$ or $PGF_{2{\alpha}}$ and 1/18 M in the absence of the hormone (control). 2) When erythrocytes were suspended in 1/15 M NaCl solution, $44.2{\pm}4.3%$ of cells were hemolyzed. Addition of $10^{12}\;M\;PGE_2$ or $PGF_{2{\alpha}}$ did not increase hemolysis. When the concentration of the hormones was increased to $10^{11}\;M$, however the degree of hemolysis increased markealy to about 80%. No further increase in hemolysis was observed at concentration of the hormones above $10^{11}\;M$. 3) The additional hemolysis due to $10^{11}\;M\;PGE_2$ and $PGF_{2{\alpha}}$ appeared to he identical regardless of absence or presence of $Ca^{++}\;(0.5{\sim}10\;mM)$ in the suspending medium. 4) In the absence of prostaglandin, the binding of $Ca^{++}$ to the erythrocyte membrane increased curvilinearly as the $Ca^{++}$ concentration increased up to 5 mM above which it leveled off. A similar dependence of $Ca^{++}$ binding on the $Ca^{++}$ concentration was observed in the presence of $10^{11}\;M\;PGE_2$ or $PGF_{2{\alpha}}$, however, the amount of $Ca^{++}$ bound at a given $Ca^{++}$ concentration was significantly higher than in the absence of the hormones. 5) As in the hemolysis, $PGE_2$ and $PGF_{2{\alpha}}$ did not affect the $Ca^{++}$ binding at a concentration of $10^{12}\;M$, but increased it by about 100% at concentration above $10^{11}\;M$. These result indicate that both tile osmotic fragility of erythrocyte and the $Ca^{++}$ binding to the erythrocyte membrane are similarly enhanced by $PGE_2$ and $PGF_{2{\alpha}}$, but these two effects are not causally related. It is, therefore, concluded that the prostaglandin-induced hemolysis is not directly associated with alterations of the $Ca^{++}$ content in the membrane.

• Journal of Environmental Science International
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• v.15 no.6
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• pp.587-592
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• 2006

The advantage of CFBC(Circulating fluidized bed combustor) is that it can apply to various fuel sources including the lower rank fuel and remove SOx by means of direct supply of limestone to the combustor without additional desulfation facility. In this paper, we denote characteristics of fly and bed ash to reuse finer limestone usually abandoned(used spec[Coarse LS] 0.1mm under 25%, new spec[Fine LS] 0.1mm under 50%). According to the results, the chemical composition of fly ash was as follows; $SiO_2\;40.8%,\;Al_2O_3\;31.9%,\;CaO\;10.7%,\;K_2O\;4.46%$ in the case of coarse limestone and $SiO_2\;41.1%,\;Al_2O_3\;31.3%,\;CaO\;10.9%,\;K_2O\;4.66%$ in the case of fine limestone. The chemical composition of bed ash was as follows; $SiO_2\;54.2%,\;Al_2O_3\;33.1%,\;CaO\;1.56%,\;K_2O\;4.34%$ in the case of coarse limestone and $SiO_2\;53.8%,\;Al_2O_3\;32.6%,\;CaO\;2.21%,\;K_2O\;4.45%$ in the case of fine limestone. It showed that there was no significant change in chemical composition. And it is conformed that there was no significant change in particle size and shapes.

• Electrical & Electronic Materials
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• v.10 no.3
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• pp.239-246
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• 1997

The ZnO is stabilize dielectric constant over a broad temperature range because its addition makes the relaxation time short. In this study, the composite oxide material (B $a_{0.85}$ $Ca_{0.15}$)Ti $O_{3}$ was mixed by ZnO additive material and the dielectric polarization characteristics was studied. The relative density was over 90[%] at all specimen in the structural characteristics. Among of the specimen, the relative density of (B $a_{0.85}$ $Ca_{0.15}$)Ti $O_{3}$ with ZnO (0.4mol) has a 95[%]. The grain size of composite oxide material with an increasing ZnO increased and it was 1.0[.mu.m]-1.22[.mu.m]. In the electrical characteristics, the charge and discharge current was increased by ZnO addition. The dielectric relaxation time was increased by space charge polarization at above 110[.deg. C] and the dielectric relaxation time was fixed by space charge polarization of para-dielectric layer at below 110[.deg. C]. The dielectric relaxation time was maximum when the grain size was small. The dielectric relaxation time is decreased with an additive material ZnO and interface polarization, existing void at the grain and grain boundary. The remnant polarization is increased and the coercive electric field is decreased by ZnO.