• Journal of dental hygiene science
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• v.13 no.3
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• pp.330-338
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• 2013

In order to explore microleakage in class V cavity based on different kinds of several dentin adhesive and composite resin, 2 kinds of composite resin was restored and exposed after applying 4 kinds of dentin adhesives. Deposited in methylene blue solution for 4 hours and cut in parallel with tooth longitudinal axis. By observing dye penetration level of enamel and dentin margins of each restored resin following conclusion was obtained. 1. In composite resin Filtek Z350XT Universal (3M/ESPE Dental Products, USA) in enamel margin, Easy Bond (3M/ESPE Dental Products) showed the lowest microleakage and this leakage was represented to be high in the order of Single Bond 2 (3M/ESPE Dental Products), Scotchbond Multi-Purpose (3M/ESPE Dental Products) and Cearfil SE Bond (Kuraray Medical Inc., Japan). In case of Filtek Z350XT Flowable (3M/ESPE Dental Products), Scotchbond Multi-Purpose showed the lowest microleakage and this leakage was represented to be high in the order of Single Bond 2, Clearfil SE Bond and Easy Bond. 2. In case of Filtek Z350XT Universal in dentin margin, Easy Bond showed the lowest microleakage and this leakage was represented to be high in the order of Scotchbond Multi-Purpose, Single Bond 2 and Clearfil SE Bond. In case of Filtek Z350XT Flowable, Scotchbond Multi-Purpose and Single Bond showed the lowest microleakage and this leakage was represented to be high in the order of Clearfil SE Bond and Easy Bond. 3. In all the groups excepting S-U group (Single Bond 2+Filtek Z350XT Universal), enamel margin showed more higher microleakage than that of dentin margin. 4. There was a difference between enamel and dentin margin among each group but it was not significant statistically (p>0.05). When summarizing this result, it is considered that composite resin and dentin adhesive could be applied selectively and particularly in case of applying 1-step self-etching dentin adhesive, this method would be advantageous for manipulation convenience and shortening of operation time.

• Journal of Wetlands Research
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• v.16 no.1
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• pp.61-72
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• 2014

To present a guideline on the construction and management of artificial wetlands for high biomass production, three emergent macrophytes (Phragmites australis, PA; Typha angustifolia, TA; and Zizania latifolia, ZL) were planted under two substrates conditions (general soil with and without moss peat) and two water levels (5 cm and 20 cm) and monitored for three years. ZL showed greater growth performance rather than the others not only at early growth phase in the first year [shoot height, 200 cm; above-ground dry weight (AGDW), 500 $g/m^2$] but also in the last year (ZL, 1,100 $g/m^2$; TA, 770 $g/m^2$; and PA, 450 $g/m^2$ of AGDW). ZL with rapid growth at the early growth phase was not affected by naturally introduced weeds, whereas slower and poorer growth of PA and TA at the early growth phase resulted in relatively higher introduction and establishment of natural weeds. In turn, such introduced weeds negatively contributed to the growth of PA and TA particularly under shallow water (5 cm) with the substrate condition including moss peat. We suggest a plant material with rapid and great growth at the early phase such as ZL for reducing possible negative influences by the natural weeds and wild animals for high biomass production in constructed wetlands. A pre-growing process in greenhouse prior to planting might be an useful option to raise the competitiveness of those species when planting PA and/or TA. In addition, we recommend that integrated weed management system with utilizing various options at the most appropriate timing must be applied for maintaining sustainable high biomass production at the artificial wetlands.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.250-256
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• 1998

D-Tagatose production from D-galactose was investigated using 35 type strains of American Culture Type Collection (ATCC) and Korean Collection for Type Cultures (KCTC) which have potential to produce D-tagatose. Enterobacter agglomerans ATCC 27987 was selected as a D-tagatose producing strain due to its short fermentation time and high production of D-tagatose. Optimization of the culture conditions for D-tagatose production by E. agglomerans ATCC 27987 was performed. Among various carbon sources, D-galactose was the most effective carbon source for D-tagatose production. As the D-galactose concentration was increased, cell growth and D-tagatose production increased. Effect of nitrogen sources on D-tagatose production was studied. Of inorganic nitrogen sources, ammonium sulfate was effective one for D-tagatose production and yeast extract was the most suitable organic nitrogen nutrient. The concentrations of inorganic compounds such as KH$_2$PO$_4$, K$_2$HPO$_4$, and MgSO$_4$$.$7H$_2$O were also optimized for D-tagatose production. The optimal medium was determined to contain D-galactose of 20 g/l, yeast extract of 5.0 g/l, (NH$_4$)$_2$SO$_4$ of 2.0 g/l, KH$_2$PO$_4$ of 5.0 g/l, K$_2$HPO of 5.0 g/l, and MgSO$_4$$.$7H$_2$O of 5 mg/l. The optimal environmental conditions in a 250-$m\ell$ flask were found to be pH of 6.0, temperature of 30$^{\circ}C$, and agitation speed of 150 rpm. D-tagatose of 0.41 g/l could be obtained in 24 h from 20 g/l D-galactose at the optimal culture condition without induction and cell concentration.

• Journal of agricultural medicine and community health
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• v.36 no.1
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• pp.36-46
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• 2011

Objectives: To investigate the experience and competence of physicians providing emergency medical services at public health sub-centers on remote Korean islands. Methods: This study enrolled 79 doctors who work at public health sub-centers on remote Korean islands. Data were collected in December 2009 via self-administered e-mail questionnaires. The response rate was 44.3%. Results: Emergent situations occurred at most (58.68%) of the public health sub-centers that were surveyed in December 2009. An average of 1.92 cases required treatment by public health physicians. Only 20.25% of the physicians were specialists in emergency medicine, while the remainder were general practitioners (GPs) without clinical experience as emergency doctors. We also found that the physicians we surveyed had insufficient knowledge of emergency medical care. At some health centers only one doctor was available, and there was no medical team in holiday, although most of the physicians indicated that the ideal number of doctors per center was two or three. In cases of emergency, patients were often sent to the mainland by ship without receiving first-aid treatment. The public health sub-centers lacked the necessary medical equipment to save lives in emergencies and lacked escort systems for emergency patients. Conclusions: The Korean government should address the importance of providing emergency care in remote areas. Health administrators should provide suitable manpower, medical equipment, guidelines for emergency medicine, and education for public health physicians on remote islands.

• Tuberculosis and Respiratory Diseases
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• v.40 no.4
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• pp.367-377
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• 1993

Background: The benefits of combination chemotherapy in unresectable non-small cell lung cancer remain uncertain. But, according to the recent reports, the response rates of cisplatin-based polychemotherapy regimens are higher than those of single agent. Also, the response rates of high-dose cisplatin group are higher than those of low-dose cisplatin group. In attemp to answer the question whether treatments, combination chemotherapy (high VPP) and combination chemotherapy with radiation therapy, improve survival in advanced non-small cell lung cancer, we begin to study. Method: Thirty-five patients above stage III, diagnosed histologically as non-small cell lung cancer, were enrolled. Among them, nineteen received a combination chemotherapy consisting of VP-16 & high-dose cisplatin (100 $mg/m^2$) and/or radiation therapy. The other group (16 subjects) received no therapy. To investigate the differences of survival and response rates between two groups and the side effects related to therapy, we reviewed patients' records. Results: 1) The overall objective response rate was 47%(9/19) with one complete remission. 2) In patients who received polychemotherapy and radiation therapy, the response rate was 60%(6/10) with one complete remission and survival rates of 3 months, 6 months and 12 months were 100%, 70% and 40%. 3) In patients who received polychemotherapy, the response rate was 33% (3/9) with no complete remission and survival rates of 3 months, 6 months and 12 months were 78%, 67% and 33%. 4) Overall, treated patients survived significantly longer (p<0.05) than non-treated patients (median survival 307 days versus 95 days). 5) Analysis of the various prognostic factors disclosed that good performance status, stage III and squamous cell type showed the good response rates. 6) The toxicities were nausea and/or vomiting (100%), alopecia (90%), anemia (79%), leukopenia (69%), thrombocytopenia (2%), increased creatinine (16%) and neurotoxicity (5%). Conclusion: According to above results, there are relatively good results that high VPP combination chemotherapy in advanced non-small cell lung cancer improves survival in the treated group than in the non-treated group. Thus, it is considerd that we select the patients with proper indications and treat them with effective chemotherpy and radiation therapy. But, because improvement related to high VPP ploychemotherapy is not marked in this study, it is necessary that we should investigate follow-up studies in many cases.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.570-584
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• 2009

The purpose of this study was to find out high school students' perception on psychologicallearning environment generated by science teachers and their attitude change related to science. The subjectsconsisted of 539 freshmen in a boys' high school pre-applied of common school group in S city. This study wasconducted with students' perception survey and classification of teachers' features according to it. The surveyabout science-related attitude was also made in early 1st semester and 2nd semester, and the students showingthe great attitude change related to science were interviewed. The results of this study revealed that statistically,students had a more positive perception on female teachers than on male ones and that according to their teachers,there were clear different in the psychological learning environment perceived by students. As for the relation of teachers' features and students' attitude change, it showed the negative effect only when the teacher was incharge of only one class, but in most of the cases, there was no meaningful correlation. The semi-structuredinterview with students with great attitude change related to science indicated that the main cause of the changewas the achievement they made in class. The interview showed that the change related to science happenedunder the indirect influence of teachers rather than direct influence. Furthermore, students wanted scienceteachers to meet the science class possessing various instruction behaviors and support behaviors. Therefore,science teachers playing an important role in students' choice of career should make efforts to realize thelearner-centered curriculum and change students' science-related attitude into a positive direction.

• Management & Information Systems Review
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• v.35 no.1
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• pp.85-116
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• 2016

The present study aims to explore the causes of employment difficulty on the basis of job applicant's interest from P-E (person-environment) fit perspective. Our approach relied on a textual analytic method to reveal insights from their situational interests in a job search during the change of labor market. Thus, to investigate the type of major interests and psychological responses, user-generated texts in a social community were collected for analysis between January 1, 2013 through December 31, 2015 by crawling the online-community in regard to job seeking and sharing information and opinions. The results of topic analysis indicated user's primary interests were divided into four types: perception of vocation expectation, employment pre-preparation behaviors, perception of labor market, and job-seeking stress. Specially, job applicants put mainly concerns of monetary reward and a form of employment, rather than their work values or career exploration, thus youth job applicants expressed their psychological responses using contextualized language (e.g., slang, vulgarisms) for projecting their unstable state under uncertainty in response to environmental changes. Additionally, they have perceived activities in the restricted preparation (e.g., certification, English exam) as determinant factors for success in employment and suffered form job-seeking stress. On the basis of these findings, current unemployment matters are totally attributed to the absence of pursing the value of vocation and job in individuals, organizations, and society. Concretely, job seekers are preoccupied with occupational prestige in social aspect and have undecided vocational value. On the other hand, most companies have no perception of the importance of human resources and have overlooked the needs for proper work environment development in respect of stimulating individual motivation. The attempt in this study to reinterpret the effect of environment as for classifying job applicant's interests in reference to linguistic and psychological theories not only helps conduct a more comprehensive meaning for understanding social matters, but guides new directions for future research on job applicant's psychological factors (e.g., attitudes, motivation) using topic analysis.

• Tuberculosis and Respiratory Diseases
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• v.42 no.4
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• pp.502-512
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• 1995

Background: One quarter to one third of patients with NSCLC present with primary tumors that although confined to the thorax are too extensive for surgical resection. Until resently standard treatment for these patients had been thoracic radiation, which produces tumor regression in most patients but few cures and dismal 5-year survival rate. The fact that death for most patients with stage III tumors is caused by distant metastases has promped a reevaluation of combined modality treatment approaches that include systemic chemotherapy. Therefore, we report the results observed in a study to evaluate the effect of multimodality treatment in locally advanced non-small cell lung cancer from 1/91 to 8/93 in CNUH. Method: We grouped the patients according to the treatment modalities and evaluated response rate, median survival and the effect of prognostic variables. Among 67 patients evaluated, twenty seven patients classified with group A, received cisplatin and etoposide containing combination chemotherapy alone, eighteen patients, classified with group B, received chemotherapy and radiotherapy, fifteen patients, group C, received neoadjuvant or adjuvant chemotherapy and surgery with/without radiation therapy, seven patients, group D, received only supportive care. Result: The major response rate for group A and B was 37% and 61% respectively. There was no statistically significant difference in response rate between A and B groups(p=0.97). The analysis of prognostic factors showed that differences of age, sex, pathology, blood type, smoking year, stage and ECOG performance did not related to improvement in survival. Median survival time was 8.6 months for group A, 13.4 months for group B, 19.2 months for group C, and 5.4 months for group D, respectively and there was statistically significant difference(p=0.003), suggesting that multimodality therapy was associated with signigicant improvement in survival. Subset survival analysis showed a significant therapeutic effect for earlier stage and good performance state(p=0.007, 0.009, respectively). A possible survival advantages were observed for major response groups. Conclusion: It was suggested that multimodality therapy for the management of patients who had stage III disease, has yielded good median survival and long survival for seleted patients. But, it is necessory to validate above result with further investigation in large scale and in prospective randomized trials.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.1
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• pp.81-91
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• 2010

IMO(International Maritime Organization) and the Shipping World rave complied with various kinds of international regulations for maritime safety and marine environmental protection, but the main reason of maritime accidents is that developing countries cannot implement maritime safety related regulations. Although Korea has been a member of the "A group" council of IMO, maritime technology transfer records of Korea are not good. To promote the project of official development assistance in Korea, it is required to select the technology which has a high degree of importance in the fields of maritime safety and has a high degree of demand on the transfer to developing countries, and to concentrate on the selected technology. So, it is necessary to draw valuation factors for maritime safety technology and to decide the priority in order among maritime safety technologies on the basis of valuation factors. Because the weights which show the degree of importance among valuation factors are different from factor to factor, interdependent relationship between factors should be considered on evaluation. In this study, the valuation factors were divided into three groups as the maturity of maritime safety technology, the promotion probability of projects and the degree of importance of technology, and the detailed factors of each group were drawn. A model which used Fuzzy AHP and limiting probability to consider the weights of importance and correlation among valuation factors was developed. To adopt this model, nine types of maritime safety technology in the field of maritime safety information were selected and points were scored for each technology through evaluation. In conclusion, first, ENC related technology was scored to be the highest as 0.0139. Second, the point of ship monitoring technology was scored as 0.0133. Last, oil spill response technology was scored as 0.0132.

• Journal of Korean Home Economics Education Association
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• v.21 no.4
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• pp.71-89
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• 2009

The purpose of this paper was to suggest effective management of clothing department in vocational high schools. Bibliographic research on ten vocational high schools' clothing departments was done. Also a survey was done to figure out what students and teachers think of clothing department education. The results were as follows. There are ten clothing departments in vocational high schools countrywide. 1493 students are enrolled in the department and they are taught by 51 teachers. Each school has two to seven laboratories. Professional subject time assignment of clothing department varies from 82 to 112 hours. Students chose clothing department in order to enter the university and their satisfaction on the department was "fair." Students' satisfaction level of professional education courses was "fair" and they felt difficulties both in theory and practice. Students answered that Embroidery/Knitting courses should be closed and Fashion Coordination be opened. Students were "fairly" satisfied with facilities for practice and felt job training was necessary. Most of them wanted to enter university after high school graduation. Teachers answered professional education curriculum was "fair." They found it necessary to improve the textbooks and felt both theory and practice difficult. They wanted Embroidery/Knitting courses to be closed and Fashion CAD course to be installed. From the teachers' view, students' prospect was better to enter university than to get a job. Teachers suffered from too much teaching-unrelated workload and wanted the number of teachers to be increased. Considering the above results, vocational high schools should concentrate their efforts on making students continue to study by extending the way to enter the same department of university as department of vocational high schools. In addition, they should develop various practice programs through field practice and educational-industrial relationship to help students get jobs. Both teachers and students think that the clothing department curriculum is difficult now. Therefore, the level of the curriculum should be adjusted. Finally, it was necessary to increase the number of teachers and to carry out teachers' training to raise quality in education.