• Restorative Dentistry and Endodontics
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• v.30 no.4
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• pp.335-343
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• 2005

Hemolytic property is a specific feature of bacteria to obtain iron which is essential for its survival in host tissues. Therefore, it is thought to be one of several factors of virulence. The purpose of this study was to investigate the hemolytic properties of Prevotella nigrescens isolated from the teeth diagnosed as pulp necrosis and apical periodontitis under the presence of hemolysin inhibitors such as $NaN_3$ and dithiothreitol. heat, various pH and cultural conditions. The results were as follows; 1. Clinically isolated P. nigrescens strains and standard P. nigrscens ATCC 33563 showed hemolytic activity. 2. P. nigrescens showed higher hemolytic activity against human erythrocytes than sheep or horse erythrocytes. 3. $NaN_3$ and dithiothreitol (DTT) reduced the hemolytic activity of P. nigrescens in a dose dependent manner (p<0.05). 4. Optimal pH for the maximum hemolytic activity of P. nigrescens was 4.0 and the hemolysin was stable under the $50^{\circ}C$, but the hemolytic activity was significantly decreased at $95^{\circ}C$. 5. P. nigrescens cultured in $10\%\;CO_2$ condition showed higher hemolytic activity than the bacteria cultured in the anaerobic condition.

• Journal of Environmental Science International
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• v.16 no.5
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• pp.665-670
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• 2007

In this study, we evaluated the property change and relationship between hematological and biochemical parameters in exposure group and control group by multiple inhalation exposure, of $NO_2$. In case of leukocyte, change of hematological property increased significantly in statistics (p<0.05) in mice experiment. in case of hematocrit of exposure group, it was of decreased significantly in statistics. the tendency of hemoglobin and hematocrit was similar to all for three case. in case of methmoglobin that of the exposure group in mice experiment was meaning increased(p<0.05). For the $NO_2$ influence in biochemical property, total protein and triglyceride was decreased but not significant in statistics, albumin was decreased in the exposure group in the animal experiments, blood urea nitrogen and creatinine increased significantly in statistics in the animal experiments. uric acid and lactate dehydrogenase in serum increased significantly in the exposure group. We have to evaluate risk assessment for the $NO_2$ of indoor air pollutant in low concentration and long time.

• Journal of the Korean Mathematical Society
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• v.39 no.1
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• pp.31-49
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• 2002

An R$^{n}$ -geometry (P$^{n}$ , L) is a generalization of the Euclidean geometry on R$^{n}$ (see Def. 1.1). We can consider some topologies (see Def. 2.2) on the line set L such that the join operation V : P$^{n}$ $\times$ P$^{n}$ \ $\Delta$ longrightarrow L is continuous. It is a notable fact that in the case n = 2 the introduced topologies on L are same and the join operation V : P$^2$ $\times$ P$^2$ \ $\Delta$ longrightarrow L is continuous and open [10, 11]. It is a fundamental topological property of plane geometry, but in the cases n $\geq$ 3, it is no longer true. There are counter examples [2]. Hence, it is a fundamental problem to find suitable topologies on the line set L in an R$^{n}$ -geometry (P$^{n}$ , L) such that these topologies are compatible with the incidence structure of (P$^{n}$ , L). Therefore, we need to study the topologies of the line set L in an R$^{n}$ -geometry (P$^{n}$ , L). In this paper, the relations of such topologies on the line set L are studied.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.678-683
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• 1996

In the fabrication processes of thin film thermoelectrics, a subsequent annealing treatment is inevitable to reduce the defects and residual stresses introduced during the film growth, and to make the uniform carrier concentration of the film. However, the diffusion-induced atomic redistribution and the broadening of p/n junction region are expected to affect the thermoelectric properties of thin film modules. The present study intends to investigate the diffusion at the p/n junctions of thermoelectric thin films and to relate it to the property changes. The film junctions of p-type(Bi0.5Sb1.5Te3)and n-type(Bi2Te2.4Se0.6)were prepared by the flash evaporation method. Aluminum thin layer was employed as a diffusion barrier between p-and n-type films of the junction. This was found to be an effective barrier by showing a negligible diffusion into both type films. After annealing treatment, the thermoelectric properties of p/n couples with aluminum barrier layer were accordingly retained their properties without any deterioration.

• Journal of Life Science
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• v.17 no.12
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• pp.1669-1674
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• 2007

The conventional histochemical stains were used to study the properties of mucosubstances of the intestine in four teleostean species, i. e., Agramus agramus, Inimicus japonicus, Epinephelus chlorostigma, and Helicolenus dactylopterus, all belonging to the order Perciformes. The following methods were used; periodic acid Schiff (PAS), alcian blue (AB) pH at 2.5, AB pH at 1.0, AB pH at 2.5-PAS, and aldehyde fuchsin (AF) pH at 1.7-AB pH at 2.5 stain. The mucosal folds of intestines show differences in species and regions. Widely distributed in all portions studied, goblet cells situated between cylinderical epithelial cells are round or ovoid in shape. They were most densely distributed in distal intestine. In the middle and. distal intestine of Epinephelus chlorostigma and all regions of intestines of Agramus agramus, Inimicus japonicus, and Helicolenus dactylopterus, the presence of both acidic and neutral mucin was confirmed. The property of acidic mucosubstance was sialomucin. Neutral mucin was only encountered in the proximal intestine of Epinephelus chlorostigma. The amount and property of mucin showed differences in species and regions. In the distal intestine of Inimicus japonicus, the amount of acidic mucin is similar to that of neutral mucin. In all regions of intestine of Agramus agramus, proximal and middle intestine of lnimicus japonicus, middle and distal intestine of Epinephelus chlorostigma, and distal intestine of Helicolenus dactylopterus, acidic mucin occured more frequently than neutral mucin. The proximal and middle intestine of Helicolenus dactylopterus have more neutral mucin than acidic mucin.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.105-106
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• 2017

Previous studies have confirmed the performance of pH reduction agents using liquid sodium phosphate based ammonium chloride as a pH reduction agent. In this study, the pH reduction performance considering economical and applicability as a practical stage and the property change analysis for the identification of the reaction mechanism of the pH reduction agent were carried out. As a result, the pH reduction performance at a low rate of the pH reducing agent was confirmed. The specific gravity of CaO decreased significantly after XRF analysis. It is also believed that this reduces the amount of Ca(OH)₂ produced and contributes to pH reduction.

• Journal of Forest and Environmental Science
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• v.25 no.3
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• pp.187-194
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• 2009

This study was carried out to investigate vegetation structure and soil property of natural habitat of Polygonatum stenophyllum to provide basic information for propagation, conservation and restoration. Habitats of Polygonatum stenophyllum were classified into Hemiptelea davidii-Robinia pseudo-acacia dominant population (Yeongwol-eup), Pinus densiflora-Hemiptelea davidii-Callicarpa japonica dominant population (Nam-myeon), and Hemiptelea davidii-Rubus crataegifolius dominant population (Gangchon-ri). The soil pH 6.49~7.28; and electron conductivity 0.10~0.19 ds/m. The average content of organic matter, total nitrogen, available $P_2O_5$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 8.24~16.45 g/kg, 0.02~0.13%, 45.67~123.67 mg/kg, 4.61~6.71 cmol(+)/kg, 0.17~0.63 cmol(+)/kg, 0.06~0.27 cmol(+)/kg and 0.03~0.30 cmol(+)/kg, respectively. Species diversity index (H'), maximum species diversity index (H' max), evenness (J') and dominance (1-J') of investigated sites ranged 1.0323 (Nam-myeon)~1.1134 (Yeongwol -eup), 1.4914 (Gangchon-ri)~1.6128 (Nam-myeon), 0.6401 (Nam-myeon)~0.7270 (Yeongwol-eup) and 0.2730 (Yeongwol-eup)~0.3599 (Nam-myeon) respectively.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.11
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• pp.1-8
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• 2003

In this paper, the dependence of silicide properties such as sheet resistance and cross-sectional profile on the dopants for source/drain and gate has been characterized. There was little difference of sheet resistance among the dopants such as As, P, BF$_2$ and B$_{11}$ just a(ter formation of NiSi using RTP (Rapid Thermal Process). However, the silicide properties showed strong dependence on the dopants when thermal treatment was applied after silicidation. BF$_2$ implanted silicon showed the most stable property, while As implanted one showed the worst. The main reason of the excellent property of BF$_2$ sample is believed to be tile retardation of hi diffusion by the flourine. Therefore, retardation of Ni diffusion is highly desirable for high performance Ni-silicide technology.y.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1143-1147
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• 1998

Enzymatic characterization of peroxidase(E.C. 1.11.1.7) from soybean sprouts was investigated. The optimum pH of the purified peroxidase was 7.0 and relatively stable at pH 6.0~7.0. And the optimum temperature was 50oC. The enzyme was most active with guaiacol as a substrate, followed by (＋)catechin, pyrogallol and p phenylenediamine. The Km values for guaiacol and H2O2 were 4.2mM and 2.5mM, respectively. L Ascorbic acid and 2 mercaptoethanol greatly inhibited the enzyme activity, while Cu2+, Co2+ and Ni2+ activated the enzyme.

• Bulletin of the Korean Chemical Society
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• v.18 no.7
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• pp.734-736
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• 1997

5-Nitrouracil and 5-nitrouridine derivatives which C-2 and C-4 oxo-groups of the pyrimidine base were replaced by thio groups were synthesized. The lipophilicities of thiopyrimidine bases were enhanced significantly as indicated by P-values. Oxygen-sulfur exchange leading to 2-thiouracil (2) and 2,4-dithiouracil (3) were associated with 1.4- and 2.6-fold increase in P-value relative to that of uracil (1). The P-values of 5-nitro-2-thiouracil (5) and 5-nitro-2,4-dithiouracil (6) were increased 13.2- and 79.8-fold relative to that of 5-nitrouracil (4). Most of the 5-nitrothiopyrimidine bases and their nucleosides were found to be moderately active against Staphylococcus aureus and Escherichia coli except 5-nitrouracil (4).