• Toxicological Research
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• v.23 no.1
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• pp.55-63
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• 2007

Diethylnitrosamine (DEN) is a nitrosamine compound that can induce a variety of liver lesions including hepatic carcinoma, forming DNA-carcinogen adducts. In the present study, microarray analyses were performed with Affymetrix Murine Genome 430A Array in order to identify the gene-expression profiles for DEN and to provide valuable information for the evaluation of potential hepatotoxicity. C57BL/6NCrj mice were orally administered once with DEN at doses of 0, 3, 7 and 20 mg/kg. Liver from each animal was removed 2, 4, 8 and 24 hrs after the administration. The histopathological analysis and serum biochemical analysis showed no significant difference in DEN-treated groups compared to control group. Conversely, the principal component analysis (PCA) profiles demonstrated that a specific normal gene expression profile in control groups differed clearly from the expression profiles of DEN-treated groups. Within groups, a little variance was found between individuals. Student's t-test on the results obtained from triplicate hybridizations was performed to identify those genes with statistically significant changes in the expression. Statistical analysis revealed that 11 genes were significantly downregulated and 28 genes were upregulated in all three animals after 2 h treatment at 20 mg/kg. The upregulated group included genes encoding Gdf15, JunD1, and Mdm2, while the genes including Sox6, Shmt2, and SIc6a6 were largely down regulated. Hierarchical clustering of gene expression also allowed the identification of functionally related clusters that encode proteins related to metabolism, and MAPK signaling pathway. Taken together, this study suggests that match with a toxicant signature can assign a putative mechanism of action to the test compound if is established a database containing response patterns to various toxic compounds.

• Research in Plant Disease
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• v.10 no.4
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• pp.217-226
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• 2004

One hundred isolates of Magnaporthe grisea from Korea and China were characterized for pathogenicity using eight Korean differential varieties(KDV), six Chinese differential varieties(CDV) and six near isogenic lines(NILs) developed in China. The restriction length polymorphism of M. grisea isolates from each country also was analyzed using MGR586 as a probe. One hundred Korean isolates classified into 17 races on KDV were grouped into 29 pathotypes on Chinese near isogenic lines(NILs). Virulence of 46% of Korean isolates against all the six Chinese NILs indicated that the current six Chinese NILs alone was not enough to be used as differential varieties in Korea. Especially, susceptibility of the BL1 carrying resistance gene Pi-b to 70% of tested Korean isolates suggested that BL1(Pi-b) may not be a useful resistance source to Korean blast. Based on the virulence assays of M. grisea populations from each country were divided into two groups. About 50% of Chinese isolates showed similarity to the 30% of the Korean isolates. Especially, the isolates from northern part of China, where Japonica rice cultivars were grown, showed high similarity to the Korean isolates, while isolates from southern part of China, where Indica rice were mainly grown, showed low similarity to Korean isolates. The genome RFLPs of Korean isolates were quite different from those of southern part of China using MGR586 as a probe. These data indicated that the physiological and genetical characteristics of M. grisea population might be determined by strong interaction with cultivated rice.

• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.222-232
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• 1999

The purpose of this study was to evaluate the effect of heated spreader on the sealing ability of lateral condensation, compared with regular cold spreader. Forty two extracted human teeth with single canal were randomly placed into 3 experimental groups, and four additional teeth were used as positive and negative controls. Each group was prepared with Ni-Ti Profile #40 using step-down technique and obturated with standardized colored gutta-percha cone by standard(cold) lateral condensation technique, warm lateral condensation technique with Endotec and hot spreader soaked in glass bead sterilizer, each with Sealapex sealer. Control groups were not obturated, but prepared. After 2 days in 2% methylene blue, the teeth were invested and made into transparent resin blocks. And then, each block was sectioned horizontally with microtome at 1, 2, 3, 4, 5 mm levels from the apex. The linear extent of dye penetration was examined with stereomicroscope at ${\times}$20 magnification. At each of 5 levels, ratio of the area of gutta-percha was obtained by calculating the area of gutta-percha to the total area of the canal. The data collected were then analyzed statistically using an analysis of variance(ANOVA) and Scheffe test. The results were as follows ; 1. All experimental groups produced the apical microleakage. 2. The mean leakage was 1.57${\pm}$0.76mm for cold spreader group, 0.86${\pm}$0.95mm for Endotec spreader group, and 0.64${\pm}$0.93mm for hot spreader group. The difference between hot spreader group and cold spreader group was statistically significant(p<0.05). 1. At the 1 mm level, the mean ratio of area of gutta-percha was 74.58${\pm}$13.15(%) for cold spreader group, 65.42${\pm}$14.62(%) for Endotec spreader group, and 80.72${\pm}$14.63(%) for hot spreader group. There was statistically significant difference between hot spreader group and Endotec spreader group(p<0.05). 2. At the 2mm level, the mean ratio of area of gutta-percha was 87.86${\pm}$11.22(%) for cold spreader group, 66.55${\pm}$14.02(%) for Endotec spreader group, and 92.93${\pm}$7.24(%) for hot spreader group. There was statistically significant difference between Endotec spreader group and other two spreader groups(p<0.05). 3. At the level 3, 4, 5 mm, there was no statistically significant difference between each group. Within the limits of the results of this experiment, warm lateral condensation technique with hot spreader soaked in a glass bead sterilizer demonstrated favorable apical sealing effect and improved density of gutta-percha mass. Thus, it is thought that this obturation technique is effective for clinical use and beneficial to reduce condensation forces, also economical and easy. Lateral condensation, Heated spreader, canal sealing, Microleakage.

• Korean Journal of Acupuncture
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• v.27 no.4
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• pp.97-109
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• 2010

Objective : To examine whether any correlation between tendency towards depression and tenderness at special acupuncture points exists, thus to explore the potential diagnostic property of acupuncture points. Methods : A total 31 subjects were included in this study. They filled out questionnaires about their mental [Beck Depression Inventory (BDI), Stress Response Inventory (SRI), Profile of Mood States (POMS)] and physical (fatigue due to overexertion, and food accumulation) symptoms. Identical weight around Alarm points (CV17, CV12, ST25, CV5, CV4, and LR13) and transport points (BL14, BL20, BL21, BL22, BL25, and BL27) was given using an algometer and the subjects rated their pain on an 11-point numerical rating scale. Heart rate variability (HRV) was also measured. Results : The subjects were divided into two groups, normal and depressive tendency groups with a cut-off point of nine on BDI. The depressive tendency group reported significantly higher values in SRI, POMS, and questionnaire for fatigue due to overexertion. In the pressure pain measurement, depressive tendency group had more pressure pain at CV12, left side of BL20, BL14, BL22 and both sides of BL21, BL25, BL27, significantly (each p<0.05). The data of HRV did not show significant differences between groups. Conclusions : People with a tendency towards depression may be prone to stress, negative mood, and fatigue due to overexertion. In addition, they may be more likely to develop tenderness at alarm points and transport points compared with healthy people. Further research is needed to confirm this finding.

• The KIPS Transactions:PartC
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• v.15C no.5
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• pp.399-408
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• 2008

Mobile WiMAX provides wireless broadband services for data communication based on IP protocol. The limitation of physical bandwidth in the radio links may cause performance degradation in providing wireless broadband services in WIMAX. To enhance the efficiency of the radio link utilization, Payload Header Suppression (PHS) is defined as an optional header compression mechanism for mobile WiMAX. It has, however, a very limited compression capability since it has very restrictive compression fields. In this paper, hence, we assumed the application of Robust Header Compression (ROHC), a header compression scheme proposed for links characterized by high bit error ratios, long round-trip times (RTT), and scarce resource, to Mobile WiMAX, and studied its performance. Previous studies on ROHC performance merely focused on the impact of high bit error rate. However, bit error is virtually transparent to ROHC in the wireless systems like WiMAX, since the MAC provides the bit error checking function. In order to evaluate the performance of ROHC in the Mobile WiMAX environments, therefore, we evaluated the performance of ROHC with respect to the packet losses instead of bit error. We investigated the impact of the ROHC parameters that are recommended for the implementation in the ROHC and compared the performance of ROHC with PHS.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.1-8
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• 2005

Measurement of convergence was/is carried out manually throughout the world for tunnels under construction. However, manual method has certain limitations in terms of applicability for the tunnels in operation. This paper describes state of the art of convergence monitoring systems which are available for measuring displacement of existing tunnels. These technologies are analyzed as follows: 1 The Sofo system using the fiber optic sensors has been applied to the stress measurement of the tunnel lining. It has not yet been used for the monitoring of tunnel convergence because of its cost and reliability 2. A TPMS(Tunnel Profile Monitoring System) using tilt sensors and displacement sensors is used for the convergence monitoring of highway tunnels, subway tunnels and underground ducts. 3. A BCS(Bassett Convergence System) using a pair of tilt sensors can be used for the convergence monitoring of tunnels, however the accuracy of the measurement has to be improved because it uses AC input voltage during data acquisition. The system has to be validated before it can be applied to the tunnels in operation. Convergence monitoring systems using TPMS and/or BCS are recommended to be evaluated and improved by a series or tests in tunnels under construction in order to be applied to the main measuring section and the tunnels in operation.

• Journal of the Korean earth science society
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• v.38 no.6
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• pp.405-420
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• 2017

We investigated the H I, He II and O III emission lines of the symbiotic star AG Peg, using the spectroscopic data secured at different phases in three periods at the Lick Observatory. We measured FWHM and the intensity of six O III Bowen lines and studied the efficiency of fluorescence mechanism. The mean FWHM of O III normal and Bowen lines observed during three time periods did not make much difference, while Bowen line intensities are about 4.0 times higher than the normal lines. Comparing the predicted and the observed ratios, we found that the observed intensities are higher than predicted intensities, except for O III ${\lambda}$ 3759.87. The O III ${\lambda}$ 3791.26 and 3754.67 intensity ratios observed only in 2001 are in good agreement with the predictions by Saraph and Seaton (1980). We obtained the Bowen efficiency parameter (R)=0.47 for 2002, but we could not find R for the other two periods of time. Because of this, based on the 2002 efficiency result, we calculated the intensity ratio of O III normal and Bowen lines relative to He II ${\lambda}$ 4685.68 and derive the efficiency variation with time period. The result showed that the efficiency is the highest in 1998 and the lowest in 2001. We conclude that the efficiencies with phase are caused by the electron temperature changes in the ionized gas. The efficiencies of AG Peg are likely to increase along with electron temperature. Our analysis results may be useful in understanding the physical conditions of the ionized shell in symbiotic star and the intensity ratio and efficiency variation.

• Korean Journal of Human Ecology
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• v.12 no.4
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• pp.417-432
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• 2003

The purpose of this study was to investigate the relationships between mother's beliefs on child rearing and children's self-perceptions. The subject of this study were comprised of 167 children aged 8-10 in Iksan & Kunsan city from Dec. 2 to Dec. 8, 2000. The children's self-perceptions were assessed by the self perceptions profile for children. Mother's beliefs questionnaire, developed by Okagaki and Sternberg, was used to obtain the data on mother's beliefs of parenting. The methods of analyses included basic descriptive categorical analysis as well as t-test, one way ANOVA-test, and multiple regression analyses. The major findings from the analyses are as follows: First, a significant difference was found in the degree of mother's beliefs about child rearing by mother's religion(p<.01), mother's education(p<.05), income(p<.001), level of life (p<.0l), mother's job, mother and fathers' agreement of child rearing(p<.05), relationship between mother and child(p<.05) in independence but a significant difference was not found in the degree of mother's beliefs about child rearing in accommodation. Second, the levels of children's scholastic performance were related to higher levels of mother's education(p<.001), mother's income(p<.001), mother and fathers' agreement of child rearing(p<.01). The levels of children's social competence was related to higher, child's gender (p<.01); girls were higher than boys. The levels of children's athletic abilities were not significant. The levels of children's physical appearance was related to higher levels of mother's education(p<.01), mother's income(p<.01), level of life(p<.05), mother's marriage(not divorce)(p<.01). The levels of children's behavioral conduct were related to higher levels of child's gender (p<.05), mother's education(p<.01), mother's income (p<.01), relationship between father and child(p<.0l). The levels of children's global self worth were related to higher levels of mother's age(p<.05), mother's education(p<.001), level of life(p<.05). Third according to the multiple regression analyses for the relationships between mother's beliefs about child rearing and children's self perceptions, mother's beliefs on the creativity were related to higher levels of children's scholastic performance, social competence, and mother's beliefs on the problem solving skills to higher levels of children's behavioral conduct and mother's beliefs on the accommodation to lower levels of children's scholastic performance, social conduct.

• The Korean Journal of Petroleum Geology
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• v.4 no.1_2 s.5
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• pp.20-26
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• 1996

In order to uncover the subsurface geological structure in the southwestern rim of the Ogcheon Fold Belt including the Cretaceous Neungju Sedimentary Basin, we analysed and interpreted the aeromagnetic anomalies over the region. The study area belongs to Muan-gun, Yeongam-gun, Gangjin-gun, Jangheung-gun, and eastem Haenam-gun. From the qualitative analysis and quantitative modeling of the reduced-to-the-pole magnetic anomalies, following things are revealed or suggested; Even though the porphyry of higher susceptibility is not crop out in the Donggang Myeon in the northwestern part of the study area, it is supposed to have intruded the Precambrian gneiss and the Cretaceous Bulgugsa granite of lower susceptibility. Two-dimemsional modeling of profile data across the sedimentary basin of Neungiu Group reveals that the northern part of the basin is deeper than the southern part, and that the maximum depth of the basin is supposed to be $3\cal{km}$ below the surface. The western flank of the basin bottom is steeper than the eastern flank. The high susceptibility value of the Neungju Group sedimentary rocks indicates that the rocks comprises large amount of volcanic materials. This fact implies that it is hard to expect hydrocarbon reservoir in the sedimentary rocks of the Neungiu Basin.

• Pediatric Infection and Vaccine
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• v.18 no.1
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• pp.68-79
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• 2011

Purpose : This post-marketing surveillance study (NCT00750360) assessed the safety and reactogenicity of an inactivated, trivalent split-virion influenza vaccine licensed for use in the Korea since 2002. Methods : Eight hundred and eighty three subjects aged 6 months received a single dose of the ${\geq}$ vaccine; an additional dose was administered to those aged <9 years and unprimed with an influenza vaccine. Four hundred and eleven subjects used diary cards to record safety information; this report presents data from these subjects. Incidence of solicited local, general and unsolicited adverse events (4-days and 21-days post-vaccination follow-up periods, respectively) were recorded. Serious adverse events (SAEs) were recorded throughout the study period. Results : Injection site pain (subjects aged <6 years: 12.6% of subjects, ${\geq}$6 years: 34.7%), fever (<6 years: 1.3%) and myalgia (${\geq}$6 years: 13.9%) were the most frequently recorded solicited local and general adverse events. Grade 3 solicited adverse events were reported by ${\leq}$4.0% subjects. No vaccine-related SAEs were recorded (KFDA criteria). Conclusion : Considering the vaccine's well-established immunogenicity and its favourable safety and reactogenicity profile across all age groups and its high coverage rate in Korea, it may be recommended as a candidate to facilitate annual seasonal influenza vaccination for all ages as part of the Korean National Immunization Program.