• Journal of dental hygiene science
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• v.14 no.1
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• pp.7-14
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• 2014

This study aims to evaluate the impact of varying exposure to dental amalgam on urinary mercury levels in children by measuring the number of amalgam-filled teeth and the variance of mercury concentration in urine over a period of 2 years. A total of 317 (male 158, female 159) elementary school children (1st~4th graders) attending 2 schools in urban regions participated in this study. At 6-month intervals, 4 oral examinations were conducted to check any variance in the conditions of dental caries and the status of dental fillings. Also, urine tests were conducted followed by a questionnaire survey. To elucidate the factors potentially affecting the mercury concentration in urine, t-test, ANOVA, chi-square test and a mixed model were used for the analysis. Regarding the status of dental fillings in line with examination time periods, deciduous teeth had more amalgam-filled surfaces than those filled with resin, whereas permanent teeth had more resin-filled surfaces than those filled with amalgam. A significant relevance was found between the exposure to dental amalgam and urinary mercury levels. Specifically, subjects whose teeth surfaces had been filled with dental amalgam showed higher urinary mercury levels than those who had no dental amalgam fillings. Based on the analysis using the mixed model, the increase in the number of teeth surfaces filled with amalgam was found to be the factor affecting the increase in urinary mercury levels. The urinary mercury levels were found to be highly associated with the exposure to dental amalgam. The more the teeth surfaces filled with amalgam, the higher the urinary mercury levels. Hence, even a trace of dental amalgam fillings can liberate mercury, affecting the variance in the urinary mercury levels. These findings suggest that some criteria or measures should be developed to minimize the exposure to dental amalgam. Moreover, relevant further studies are warranted.

• Journal of dental hygiene science
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• v.13 no.1
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• pp.36-44
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• 2013

The purpose of this study was to provide basic data for healthy and effective dental management by providing the knowledge and information on periodontal health promotion as well as high dental health interests, by doing a comparative analysis of the effect of dental health knowledge and oral hygiene management skills of people in their 20s on periodontal health status assessment, to find periodontal disease early and prevent it targeting 130 adults in their 20s who visited dental hygienic lab for comprehensive dental hygiene care and treatment from September 25 to October 30. The data collected used SPSS 18.0. To present the technical characteristics of the data, frequency was used and chi-squared test through cross-analysis was conducted to investigate dental health knowledge and the relevance between the variables of oral hygiene management skills of general characteristics. To examine periodontal health status assessment, t-test and One-way ANOVA and Turkey post-hoc tests were carried out at the 5% significance level. Regression analysis was performed to investigate the impact of dental health knowledge and oral hygiene management skills on dental health status assessment. As a result of this study, as dental health knowledge on tooth brushing of people in their 20s increased, plaque index reduced, as dental health knowledge on periodontal disease increased, plaque index reduced. Dental health status assessment according to a total number of times tooth brushing, tooth brushing methods, whether to use dental hygiene devices, smoking status, drinking frequency per week, whether to have oral health education was statistically significant. To improve the level of dental health knowledge and oral hygiene management skills, oral health education should be strengthened as well as the publicity through the media to have the information on oral health and learn it.

• Korean Journal of Environmental Agriculture
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• v.33 no.2
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• pp.103-110
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• 2014

BACKGROUND: Azadirachta indica has been widely used as environment-friendly organic materials because of its insecticidal properties. This study was carried out to investigate the acute toxicity and the subacute toxicity of Azadirachta indica extract(AIE) in rats. METHODS AND RESULTS: For the oral acute toxicity test, Sprague-Dawley rats were gavaged with 2.0 g/Kg bw of AIE. The $LD_{50}$ value was greater than 2.0 g/Kg bw for both male and female rats. For the subacute toxicity study, rats were treated with AIE at doses of 0.5, 1.0, 2.0 mg/Kg bw once a day for 4 weeks(n=10 animals per each group). There were no significant changes in body weight, food intake and water consumption observed during the experimental duration. In addition, no difference of relative kidney weight was observed among all treated groups. Serum creatinine level in the AIE 2.0 g/Kg group increased significantly compared with that of control group in male rats, but serum blood urea nitrogen was significantly decreased in a dose-dependent manner (p<0.05). Significant increase of serum cholesterol levels were observed in all AIE groups, compared with the control group, in the female rats (p<0.05). However, histopathological examination of the kidney did not reveal any significant lesions in all groups. CONCLUSION: On the basis of results, it could be concluded that oral administration AIE didn't cause any toxic response in kidney, except the increased serum cholesterol.

• International Journal of Highway Engineering
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• v.6 no.3 s.21
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• pp.1-7
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• 2004

Roads, like bikeways, parkways and walks, are to be just capable of supporting light traffic and traveling public, but they are required to be human friendly and environmental-oriented. Lately soil-solidifier mixture, a kind of soil-cement, has developed and has been applied to the recycling and environment-oriented pavement as the surfacing material. Soil-solidifier pavement structure has been designed by only experience. To design this pavement mechanically, it is necessary to find out basic engineering properties of soil-solidifier mixture. This study focuses on finding out mechanical characteristics of the mixture according to mixture proportions and aging. Test molds with various mixture proportions are made, and then unconfined strength tests are performed for test molds with aging of the mixture. As the result of this study, it is found that the strength of the mixture increases with amount of cement and that maximum strength is achieved at 6%$\sim$8% of the ratio of solidifier and water. The strength increase rapidly until 14 days, after then slowly. After 28 days the strength of the mixture approaches to the constant value. The heat of hydration during curing of the mixture is measured no significantly. It also shows that temperature characteristics of the mixture is similar to that of soil. Since this mixture is mixed with soil and is able to improve engineering problems in pavement due to temperature, this mixture is expected to use effectively in the environment-oriented pavement for light traffic.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.113-130
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• 2002

In this paper, we developed DNL(Dynamic Network Loading) model based on Moving cell theory to analyze the dynamic characteristics of traffic flow in congested network. In this paper vehicles entered into link at same interval would construct one cell, and the cells moved according to Cell following rule. In the past researches relating to DNL model a continuous single link is separated into two sections such as running section and queuing section to describe physical queue so that various dynamic states generated in real link are only simplified by running and queuing state. However, the approach has some difficulties in simulating various dynamic flow characteristics. To overcome these problems, we present Moving cell theory which is developed by combining Car following theory and Lagrangian method mainly using for the analysis of air pollutants dispersion. In Moving cell theory platoons are represented by cells and each cell is processed by Cell following theory. This type of simulation model is firstly presented by Cremer et al(1999). However they did not develop merging and diverging model because their model was applied to basic freeway section. Moreover they set the number of vehicles which can be included in one cell in one interval so this formulation cant apply to signalized intersection in urban network. To solve these difficulties we develop new approach using Moving cell theory and simulate traffic flow dynamics continuously by movement and state transition of the cells. The developed model are played on simple network including merging and diverging section and it shows improved abilities to describe flow dynamics comparing past DNL models.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.33-43
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• 2002

Travel choice behavior is affected by real-time traffic information. Recently, in urban area, real-time traffic information is provided by several instruments such as transportation broadcasting, internet PC network and variable message sign, etc. Furthermore, it has been increasing for urban travelers to use real-time traffic information provided by several instruments. The purpose of this study is to analyze the effects of advanced traveler information on urban worker's travel choice behavior. Among several Advanced Traveler Information System(ATIS) employed in urban area. This study focuses on examining the effects of transportation broadcasting on urban worker's travel choice behavior. This study attempts to examine traveler's mode change behavior in the pre-trip stage and traveler's route change behavior in the on-route stage. For this study, the survey data collected from Daegu City in 2000 is used. For empirical analysis, several nested logit models are estimated, and among them, the best models are reported in this paper. Furthermore, based on the empirical models estimated for this research, important findings and their policy implications are discussed.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.59-77
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• 2000

This study was carried out to investigate on several factors, which contaminative the water quality through the water pipe during feeding water, in 42 largescaled apart-ments(total 84 cases) and assayed the Volatile Organic Compounds(VOCs) and concen-tration of heavy metals that inflow and outflow in reservior water in Jeonnam area(Mokpo, Suncheon, Yeosu) from January 1999 to December 1999. The results obtained were summarized as follows ; 1. The quality of the water pipe composition in the order of frequency in the quality of water pipes were Copper(45.2%)> Zinc(38.9%)> Stainless steel(9.5%)> PVC(4.8%)> PM(2.4%) in observing 42 sites. All of the drain pipes were used the cast iron quality. 2. The result of certification curve from 12 items(17kind) of VOCs was $1.0-4.0{\mu{g}}/{\ell}$ range, a coefficient of correlation was shown 0.99 over. A MDL of each substance range was within $0.1-1.0{\mu{g}}/{\ell}$. 3. The result of the assay, 5 kinds(Viny chloride, Dichloromethane, Ethylbenzene, M,P-xylene, Styrene) of the VOCs of 14 kinds was not detected and the other items were detected slightly. The detection rate of one item and over in total VOCs samples, were 25.9% in inflow and 27.9% in outflow. And frequency of detect in inflow/outflow of THM(Chloroform, Bromodichloro-methane, Dibromochloromethane, Bromoform) were shown higher than 94.1%, 97.0% each stages. It comes to the conclusion that all of the samples were reason able for drinking water standards. 4. The coefficient of correlation were reasonable, it shown 0.999 over in $0.1-1.0{\mu{g}}/{\ell}$ of a measuring range conditions of 4kinds in organic substance(Zn, Cu, Fe, Mn). 5. The results were showed suitability in 78 cases(92.9%) and unsuitability in 6 cases (7.1%), in 84 cases of in organic substances. Compare to inflow stage, mean concentrations of heavy metal, were increased slightly in Zn, Cu, Fe except Mn than outflow stage. The result of the mean concentration in organic substance inflow and outflow in the apartment water tank using Pair-compared T-test, in 95% reliance index, were $0.179mg/{\ell}(0.151-0.307mg/{\ell})$ in Zinc, $0.136mg/{\ell}(0.113-0.230mg/{\ell})$ in Copper, $0.052mg/{\ell}(0.048-0.098mg/{\ell})$ in Fe, and there was a bit growing tendency but there was no differece in Mn. 6. The mean concentration of Copper which used Cu pipe as a water supply pipe in apartment were $0.216mg/{\ell}(0.161-0.338mg/{\ell})$ in case of the Zine pipe were $0.286mg/{\ell}(0.204-0.435mg/{\ell})$. It shows that the detection rate was more higher than the other material used in Cu or Zn as the water supply pipe. We supposed to Cu and Zn substance were gushing out water supply pipe.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.134-141
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• 1998

Primary lung cancer has recently increased progressively in its incidence in Korea. It is clearly evident that surgical resection offers the best offortunity for cure of non-small cell carcinoma. This study was designed to analyse the clinical data of 100 primary non-small cell carcinoma patients who underwent lung resection surgery from January 1992 to July 1995 at the department of Thoracic and Cardiovascular Sugery, Kyungpook National University Hospital. There were 86 males and 14 females(6:1). In the age distribution, the peak incidence was recorded in the seventh decade(43%). The methods of tissue diagnosis were bronchoscopic biopsy in 53 patients(50.5%), percutaneous needle aspiration in 17 patients(16.2%), transbronchial lung biopsy in 11 patients(10.5%), mediastinoscopic biopsy in 2 patients (1.9%), sputum cytology in 2 patients(1.9%), and thoracotomy in 20 patients(19.0%). Fifty-five lobectomies, 22 pneumonectomies, 15 bilobectomies, 2 segmentectomies, 4 sleeve lobectomies, a sleeve pneumonectomy, and a wedge pneumonectomy were performed. Operative mortality occured in 4 cases(sepsis in 2 cases, respiratory failure in 1 case, and acute myocardiac infarction in 1 case). The histologic types of tumor were 67 squamous cell carcinomas, 26 adenocarcinomas, 6 large cell carcinomas, and an adenosquamous cell carcinoma. Eighteen patients with N2 mediastinal lymph node metastases had 8 squamous cell carcinomas(11.9%), 9 adenocarcinomas(34.6%), and a large cell carcinoma(16.7%). The primary tumors in these patients were in the right upper lobe in 4 patients, the right middle and lower lobe in 9 patients, the left upper lobe in 3 patients, and the left lower lobe in 2 patients. With regard to pathologic stages, 45 patients had stage I disease; 13 patients, stage II; 36 patients, stage IIIa; 5 patients, stage IIIb; and 1 patient, stage IV. The overall actuarial survival rate was 77.5% at 12 months, 56.1% at 24 months and 43.7% at 43 months. The actuarial survival rates at 43 months were 81.3% in Stage I, 20.8% in Stage II, 27.9% in Stage IIIa, 25.0% in Stage IIIb and 33.3% in Stage IV. These facts suggest that early detection and surgical resection are recommended for favorable postoperative survival in non-small cell lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.64 no.4
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• pp.278-284
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• 2008

Background: TRAIL is a promising anticancer agent which induces selective tumor cell death due to a unique receptor system that includes death receptors and decoy receptors. DR5 TRAIL receptor is an originally identified p53-regulated death receptor gene that was induced, by doxorubicine, only in cells with a wild-type p53 status. We investigated that focused on the correlation between the DR5 and p53 expressions in non-small cell lung cancer (NSCLC). Methods: Immunohistochemical analysis, with using avidin-biotinylated horseradish peroxidase complex, was carried out in 89 surgically resected NSCLC formalin-fixed paraffin-embedded tissue sections. As primary antibodies, we used anti-DR5 polyclonal antibody and anti-p53 monoclonal antibody. A negative control was processed with each slide. The positive tumor cells were quantified twice and these values were expressed as percentage of the total number of tumor cells, and the intensity of immunostaining was expressed. The analysis of the DR5 expression was done separately in tumor area and in a nearby region of normal tissue. Results: The DR5 expression was high in the bronchial epithelium (89% of cases) but this was almost absent in type I & II pneumocytes, lymphocytes and smooth muscle cells. High DR5 expression rate in tumor was seen in 28% (15/53) of squamous cell carcinomas, in 47% (15/32) of adenocarcinomas and, in 50% (2/4) of large cell carcinomas. The DR5 expression did not show any statistical significance relationship with the T stage, N stage, or survival. However, the DR5 expression showed significant inverse correlation with the p53 expression. (p< 0.01). Conclusion: We demonstrated that the DR5 expression in NSCLC via immunohistochemical analysis is relatively tumor-specific except for that in the normal bronchial epithelium and it is significantly dependent on the p53 status. This might be in vivo evidence for the significance of the DR5 gene as a p53 downstream gene.

• The Journal of Korean Academic Society of Nursing Education
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• v.3
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• pp.99-116
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• 1997

In response of the increasing demand for professional degree in nursing, some university in Korea offers RN-BSN program for R. N. from diploma in nursing. However, RN-BSN program in Korea is in formative period. Therefore, the purpose of this survey study is for the comparative analysis of RN-BSN curriculum in Korea and U.S.A. In this study, subjects consisted of 18 department of nursing in university and 5 RN-BSN programs in Korea and 18 department of nursing in university and 12 RN-BSN programs in U.S.A. For earn the degree of Bachelor of Science in Nursing, the student earns 134 of mean credits in U.S.A., whereas 150.3 of mean credits in Korea. The mean credit for clinical pratice is 30.1 in U.S.A., whereas 23.9 in Korea. Students are assigned to individually planned clinical experiences under the direction of a preceptor in U.S.A. In RN-BSN program, total mean credits through lecture and clinical practice for earn the degree of BSN is 35.5(lecture : 27.7, practice ; 7.8)in U.S.A., whereas,48.1 (lecture;42.1, practice;6.0) in Korea. RN-BSN program can be taken on a full-or-part time basis in U.S.A., whereas didn't in Korea. Especially, emphasis is place on the advanced nursing practicum that focus on the role of the professional nurse in providing health care to individuals, families, and groups in community setting in U.S.A. 27.7 of mean credits was earned through lecture in U.S.A., whereas 42.1 of mean credits in Korea. It means that RN-BSN program in Korea is the lesser development in teaching method and appraisal method than in U.S.A. Students of RN-BSN program in U.S.A. can earns credit through CLEP, NLN achievement test, portfolio review session etc as well as lecture. Therefore, the authors suggests some recommendations for the development of curriculum of RN-BSN program in Korea based on comparative analysis of RN-BSN curricula in U.S.A. and Korea. 1. The curriculum of RN-BSN Program in nursing was required to do some alterations. Nursing care, today, is complex and ever changing. According to change of public need, RN-BSN curriculum intensified primary care program in community setting, geriatric nursing, marketing skill, computer language. 2. The various and new methods of earning credit should be developed. That is, the students will earn credits through the transfer of previous nursing college credits, accredited examination of university, advanced placement examination, portfolio review session, case study, report, self-directed learning and so on. Flexible teaching place should ile offered. 3. Flexible teaching place should be offered. The RN-BSN curriculum should accommodate each RN student's geographical needs and school/work schedule. Therefore, the university should search a variety of teaching places and the RN students can obtain their degrees comfortably throughout the teaching place such as lecture room inside the health care agency and establishment of the branch school in each student's residence area. 4. The RN-BSN program should offer a long distance education to place-bound RN student in many parts of Korea. That is, from the main office of university, the RN-BSN courses are delivered to many areas by Internet, EdNet (satellite telecommunication) and other non-traditional methods. 5. For allowing RN student to take nursing courses, program length should be various, depending upon the student's study/work schedule. That is, the various term systems such as semester, three terms, quarter systems and the student's status like full time or part time should be considered. Therefore, the student can take advantage of the many other educational and professional opportunities, making them available during the school year.