• Economic and Environmental Geology
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• v.56 no.5
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• pp.533-545
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• 2023

In this study, an investigation was conducted on the features, events, and processes (FEP) that could impact the long-term safety of the natural barriers constituting high-level radioactive waste geological repositories. The FEP list was developed utilizing the IFEP list 3.0 provided by the Nuclear Energy Agency (NEA) as foundational data, supplemented by geological investigations and research findings from leading countries in this field. A total of 49 FEPs related to the performance of the natural barrier were identified. For each FEP, detailed definitions, classifications, impacts on long-term safety, significance in domestic conditions, and feasibility of quantification were provided. Moreover, based on the compiled FEP list, three scenarios that could affect the long-term safety of the disposal facility were developed. Geological factors affecting the performance of the natural barrier in each scenario were selected and their relationships were visualized. The constructed FEP list and the visualization of interrelated factors in various scenarios are anticipated to provide essential information for selecting and organizing factors that must be considered in the development of mathematical models for quantitatively evaluating the long-term safety of deep geological repositories. In addition, these findings could be effectively utilized in establishing criteria related to the key performance of natural barriers for the confirmation of repository sites.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.317-334
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• 1992

Weed flora and floristic composition were reviewed in lowland rice field and upland crop area. For lowland rice field weed flora was not much changed since 1971. About 29 weed species belonged to 18 families were occurred. However, floristic composition of dominant weed species has greatly changed mainly due to introduction of herbicides. The predominant weed species in 1971 when herbicide was not used were Rotala indica, Eleocharis acicularis, Monochoria vaginalis, Echinochloa crus-galli, while these for in 1991 were Eleocharis kuroguwai, Sagittaria pygmaea, S. trifolia, Echinochloa crus-galli and M, vaginalis, respectively. In 1981 weed survey, E. crus-galli was no longer troblesome weed. However, this species became important again thereafter by introduction of herbicide mixtures with pyrazolate, bensulfuron-methyl or pyrazosulfuronethyl. For upland crop area, 216 weed species belonged to 46 families were recorded. One hundred and sixtyfive of these were grown in winter crop area while 189 weed species occurred in summer crop area, respectively. Among these, 138 weed species were grown in both crop seasons. In general, summer crops had less number of weed species compared to winter crops. Even though the dominant weed species varied by crop the most common weeds were Chenopodium album, Alopecunrs aqualis, Stellaria alsine and S, media for winter crops and Digitaria sanguinalis, Portulaca oleracea, Chenopodium album and Acalypha australis for summer crops, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.135-166
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• 1977

Some biochemical features of varietal variation in seed protein and their implications for soybean breeding for high protein were pursued employing 86 soybean varieties of Korea, Japan, and the U.S.A. origins. Also, studied comparatively was the temporal pattern of protein components accumulation during seed development characteristic to the high protein variety. Seed protein content of the 86 soybean varieties varied 34.4 to 50.6%. Non-existence of variety having high content of both protein and oil, or high protein content with average oil content as well as high negative correlation between the content of protein and oil (r=-0.73$^{**}$) indicate strongly a great difficulty to breed high protein variety while conserving oil content. The total content of essential amino acids varied 32.82 to 36.63% and the total content of sulfur-containing amino acids varied 2.09 to 2.73% as tested for 12 varieties differing protein content from 40.0 to 50.6%. The content of methionine was positively correlated with the content of glutamic acid, which was the major amino acid (18.5%) in seed protein of soybean. In particular, the varieties Bongeui and Saikai ＃20 had high protein content as well as high content of sulfur-containing amino acids. The content of lysine was negatively correlated with that of isoleucine, but positively correlated with protein content. The content of alanine, valine or leucine was correlated positively with oil content. The seed protein of soybean was built with 12 to 16 components depending on variety as revealed on disc acrylamide gel electrophoresis. The 86 varieties were classified into 11 groups of characteristic electrophoretic pattern. The protein component of Rm=0.14(b) showed the greatest varietal variation among the components in their relative contents, and negative correlation with the content of the other components, while the protein component of Rm=0.06(a) had a significant, positive correlation with protein content. There was sequential phases of rapid decrease, slow increase and stay in the protein content during seed development. Shorter period and lower rate of decrease followed by longer period and higher rate of increase in protein content during seed development was of characteristic to high protein variety together with earlier and continuous development at higher rate of the protein component a. Considering the extremely low methionine content of the protein component a, breeding for high protein content may result in lower quality of soybean protein.n.

• Clinical and Experimental Pediatrics
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• v.48 no.4
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• pp.363-368
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• 2005

Purpose : The aim of this study is to identify where and how adolescents acquire cigarettes and how many were asked for identification while purchasing cigarettes. Methods : This study was conducted in 2003; participants were 2,200 students in middle and high schools, aged from 13 to 18 years old(males 1,098; females 1,102) in Ansan, Korea. The questionnaire assured them of anonymity, and self-administered in school. The data was analyzed with chisquare test for trends. Results : The prevalence of smoking was about 20 percent among respondents, was higher in males than in females, and in older students than in younger students(P<0.001). The most frequent source of cigarettes was purchased from a store(36.3 percent). About 29.2 percent of the students borrowed from friends or family members. By sex, the main sources of cigarettes were purchase from a store and borrowing. Younger students were borrowed more cigarettes; older students purchased more cigarettes from stores. Only 48.8 percent were asked for proof of age during their purchase. Of those asked for proof of age, about 73.3 percent answered that this made it difficult to buy cigarettes(P<0.001), and they thought that it was more difficult when asked for a photo ID than simply being asked their age(P=0.019). Conclusion : So far, there has been no systemic prevention of adolescents' smoking. It is difficult for minors to purchase cigarettes if asked for proof of age, but most minors go to stores to purchase cigarettes. Therefore, prevention efforts should include educating retailers not to sell cigarettes to minors and enforcing existing laws requiring youth to provide proof of age when attempting to buy cigarettes.

• Clinical and Experimental Pediatrics
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• v.51 no.2
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• pp.188-203
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• 2008

Purpose : Asthma is one of the most common chronic childhood disease. Education of asthmatic children and their families about asthma and its management may improve disease control, reduce symptoms, and improve school performance. The aim of the study was to evaluate the effects of an intensive asthma education program in asthmatic children and their families on outcome measure of asthma management behavior scale, knowledge about asthma, self efficacy scale and quality of life. Methods : Fifteen asthmatic children and their families were invited the intensive asthma education program which including allergen avoidance, management of asthma, correct use of the inhalation devices and control of exercise-induced asthma (study group). Fifteen asthmatic children and their families those who did not participate this program were served as control group. Participants were asked to complete a written questionnaire before and 3-month after the program. Results : After completing the intensive education program, significant improvement of the childrens asthma management behavior scale (27.1 vs. 32.2, P=0.011), belief and knowledge about asthma (14.2 vs. 17.9, P<0.001), self efficacy (47.9 vs. 49.7, P=0.091) and quality of life (79.6 vs. 88.6, P<0.001) was noted in the study group by measuring questionnaires. There are increasing tendencies in parental asthma management behavior scale and knowledge about asthma. Conclusion : This intensive asthma education program is effective in improving asthma control, self efficacy and quality of life of asthmatic children. This should serve as a national model for family-based programs for asthmatic children and their families.

• Pediatric Infection and Vaccine
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• v.6 no.2
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• pp.245-252
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• 1999

Purpose : The aim of this study is to determine the age-specific seropositivity and the level of measles specific IgG in adults and to evaluate herd immunity to measles in Korea, the measles specific IgG were measured from the sera of adults over ages of 20 in Korea. Methods : 156 sera were collected from 156 out-patients over ages 20, who had visited clinical laboratory from June to July in 1997 at Korea University Ansan Hospital. The histories of natural measles or vaccination were not undertaken. Measles specific IgG titers were measured using ELISA method($SIA^{TM}$ Measles IgG Kit Co. St. Louis. Mo). Results : The results obtained from this study were as follows. 1) The seropositivity of measles specific IgG in adults was 94.9%. And there were no significant differences in their age and gender. 2) The mean measles-specific IgG titer was $238{\pm}84AU/mL$. And there were no significant differences in age and gender, except significant lower in 4th decades than other age groups. And there were no significant correlations between age and measles specific IgG level. Conclusion : In conclusion, a seropositivity of in adults was 94.9% which was higher than that of adolescents(91.2% in previous study), and antibody level was similar with adolescents. The herd immunity of the adults were considered to enough for protecting the transmission of measles in the community. For the eradication of measles in Korea, more efforts will be required to increase the vaccine coverage rate in children and adolescents.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.4
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• pp.30-47
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• 2013

Objectives: The purpose of the present study is to investigate anti-depressive effects of Samul-tanggahyangbuja (SGH) on ovariectomized and chronic mild stress (CMS) induced rats. Methods: Ovariectomized rats were exposed to CMS for 4 weeks. Changes of depression behavior were tested by using sucrose intake test (SIT), elevated plus maze (EPM), forced swimming test (FST) and Morris water maze test (MWMT) in rats until being orally medicated with SGH (100 or 400 mg/kg/day). In addition, the serum levels of corticosterone (CORT), IL-4, IL-$1{\beta}$ and changes of 5-HT in the brain were measured. Results: 1. SGH 400 mg/kg treated group (SGH 400) significantly increased amount of sucrose intake compared with the control group (p<0.05). 2. SGH 100 mg/kg treated group (SGH 100) and SGH 400 significantly increased the time spent in the open arms of the EPM compared with the control group (p<0.01). SGH 400 also significantly increased the number of crossing of the open and closed arms compared with the control group (p<0.05). 3. SGH significantly shortened the immobility time in FST compared with the control group (SGH 100 p<0.05, SGH 400 p<0.01). 4. SGH significantly increased performance of acquisition trials compared with the control group (p<0.05, on day 4, 5 of SGH 100 and 400). SGH 400 also significantly increased performance of retention trials compared with the control group (p<0.05). 5. The serum levels of corticosterone and IL-4 were not significantly different among the groups. There were no changes on the serum levels of corticosterone, IL-$1{\beta}$ and IL-4 after administration with SGH. 6. SGH 400 significantly increased the level of 5-HT in the hippocampus compared with the control group (p<0.05). SGH significantly increased the levels of 5-HT in the hypothalamus compared with the control group (SGH 100 p<0.05, SGH 400 p<0.01). Conclusions: These results suggest that SGH has the anti-depressive effect on ovariectomized rat and affect 5-HT system rather than hypothalamic-pituitary-adrenal (HPA) axis and immune system.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.6 no.1
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• pp.1-9
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• 2003

Purpose: To investigate the relation of the gastric epithelial cell proliferation, apoptosis and genotypes of H. pylori in children. Methods: Histologic grading by updated Sydney system, PCNA immunostaining, TUNEL method and the genotypes (cagA, picB and iceA) by PCR were performed in H. pylori positive (N=20) and negative (N=20) gastric biopsy specimens. Results: PCNA index was significantly different between H. pylori positive children ($77.4{\pm}13.12$) and H. pylori negative children ($52.3{\pm}12.20$) (p=0.000). There were positive correlations between PCNA index and H. pylori density (r=0.624, p=0.000), polymorphonuclear neutrophil activity (r=0.460, p=0.005) and chronic inflammation (r=0.433, p=0.009). Apoptosis index of H. pylori positive children ($0.70{\pm}0.411$) was significantly higher than of H. pylori negative children ($0.14{\pm}0.201$) (p=0.000). Positive correlations between apoptosis index and H. pylori density (r=0.691, p=0.000), polymorphonuclear neutrophil activity (r=0.585, p=0.000) and chronic inflammation (r=0.535, p=0.001) were noted. As PCNA index increased, apoptosis index significantly increased (r=0.527, p=0.001). The positive rates of genotypes were cagA 90%, picB 75%, iceA1 60% and iceA2 15%, respectively. There were no significant correlations between the status of the genotypes and PCNA index, apoptosis index, the endoscopic findings and the histologic findings. Conclusion: PCNA index and apoptosis index in H. pylori positive children were higher than in H. pylori negative children but were not related to H. pylori genotypes. This study suggested that correlatively increased gastric epithelial cell proliferation and apoptosis are important to pathogenesis of H. pylori infection in children.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1337-1347
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• 2009

Purpose:Taurine (2-aminoethanesulfonic acid) is a simple sulfur-containing amino acid. It is abundantly present in tissues such as brain, retina, heart, and skeletal muscles. Current studies have demonstrated the neuroprotective effects of taurine, but limited data are available for such effects during neonatal period. The aim of this study was to determine whether taurine could reduce hypoxic-ischemic (HI) cerebral injury via anti-apoptosis mechanism. Methods:Embryonic cortical neurons isolated from Sprague-Dawley (SD) rats at 18 days gestation were cultured in vitro. The cells were divided into hypoxia group, taurine-treated group before hypoxic insult, and taurine-treated group after HI insult. In the in vivo model, left carotid artery ligation was performed in 7-day-old SD rat pups. The pups were exposed to hypoxia, administered an injection of 30 mg/kg of taurine, and killed at 1 day, 3 days, 1 week, 2 weeks, and 4 weeks after the hypoxic insult. We compared the expressions of Bcl-2, Bax, and caspase-3 among the 3 groups by using real- time polymerase chain reaction (PCR) and western blotting. Results:The cells in the taurine-treated group before hypoxic insult, although similar in appearance to those in the normoxia group, were lesser in number. In the taurine-treated group, Bcl-2 expression increased, whereas Bax and caspase-3 expressions reduced. Conclusion:Taurine exerts neuroprotective effects onperinatal HI brain injury due to its anti-apoptotic effect. The neuroprotective effect was maximal at 1-2 weeks after the hypoxic injury.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.811-817
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• 2009

Purpose : Inhaled corticosteroids (ICS) are used as first-line agents for the treatment of persistent asthma; however, their use is accompanied by apprehension of potential systemic adverse effects. This study aimed to assess the effects of ICS on bone mineral density (BMD) and bone metabolism in children with asthma. Methods : From February 2008 to September 2008, 26 asthmatic children treated with ICS (ICS group), 15 asthmatic children treated with leukotriene receptor antagonist (LTRA) (LTRA group), and 30 healthy children (Control group) were selected from the Korea University Anam Hospital. BMD and serum bone-specific alkaline phosphatase (BALP) levels were measured. The asthmatic children underwent spirometry and methacholine bronchial challenge test. Results : There were no significant differences in BMD in the lumbar spine (P=0.254) and proximal femur (P=0.297) among the 3 groups. The serum BALP levels were significantly higher in both the ICS (P=0.017) and LTRA (P=0.025) groups than in the Control group. None of the parameters pertaining to ICS use, such as the mean daily dose during the last 6 months, the total cumulative dose, duration of use, and age of commencement of use, showed significant correlations with BMD (P>0.05 for all parameters). Conclusions : We demonstrated that a low dose of ICS does not exert any significant adverse effect on bone metabolism in asthmatic children. These findings support the current recommendations with regard to the use of ICS for asthmatic children.