• Journal of Periodontal and Implant Science
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• v.38 no.3
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• pp.475-482
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• 2008

Purpose: To evaluate the safety and efficiency of bone regenerative abilities of silk fibroin nanomembrane(Nanoguide-S) Material and Methods: The objects were 38 patients who had large defect at extraction sockets caused by chronic periodontitis and silk fibroin nano matrix were used on experimental group(N=19) and PLA/PLGA matrix were used on control group(N=19). The width, height, and length by crown-apical direction(socket depth) of defects were measured with the occlusal plane as a reference plane, and tooth axis direction, perpendicular to tooth axis direction were measured on radiographs at 3 months pre-operative, 3 months post-operative. Result: Tissue response to silk fibroin nano matrix and Biomesh were clinically satisfactory and complications such as swelling, exudation, ulceration and vesicles were not found except the ordinary discomfort of operated portion. 3 months later, the width, height, and length by crown-apical direction (socket depth) of defects were clinically improved in both groups with no significant difference. 3 months later radiolucency of tooth axis direction and perpendicular to tooth axis direction were all increased in both groups with no significant difference. Conclusion: By these results biodegradadable silk fibroin nano matrix was efficient in GBR on alveolar bone resorption caused by periodontitis compared to Biomesh.

• Journal of Periodontal and Implant Science
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• v.38 no.3
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• pp.521-528
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• 2008

Purpose: Tunneling is a periodontal surgical procedure that creates access for patient cleansing and maintenance within the furcal area of a molar tooth with severe furcation involvement. Up to date, there are few studies about a long term clinical and radiographic stability of tunneling. The purpose of this retrospective study is to evaluate the long term prognosis after tunnel preparation of molars with through and through furcation. Material and Methods: 25 teeth of 23 patients aged 36 to 70 (mean age 51.7) were treated surgically with tunnel preparation. These cases were followed for 2 to 13 years (mean 6.5years) after surgery. Patients were recalled for an evaluation which was based on a questionnaire, a clinical examination, and radiographic analysis. Clinical assessment included plaque index, caries registration, probing pocket depth, bleeding on probing, tooth mobility. Baseline and over 2-year follow-up radiographs were collected and evaluated for this study. Result: 3 teeth(12%) had been extracted and 1 tooth(4%) hemisected. Root caries was detected in 3 teeth(12%). Thus 72% of the teeth were still caries tree and in function. Clinical parameters including PI, PD, BOP, mobility showed somewhat favourable results. Radiographic furcal bone loss showed no statistically significant difference compared to interproximal crestal bone loss ($3.59{\pm}1.69%$ vs $3.42{\pm}2.95%$) when root length was used as reference. There was no correlation between root trunk length and furcal bone loss. Conclusion: Over 2 years after tunneling procedure, teeth showed a clinically and radiographically stable condition, despite of slight root caries and alveolar bone loss within clinically acceptable range. The tunnel procedure may be considered as a viable periodontal treatment option for molar teeth with severe furcation involvement in individuals following a regular maintenance program.

• Particle and aerosol research
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• v.9 no.1
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• pp.7-21
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• 2013

Twelve-hour size-resolved atmospheric aerosols were measured to determine size distributions of water-soluble organic carbon(WSOC) during daytime and nighttime, and to investigate sources and formation pathways of WSOC in individual particle size classes. Mass, WSOC, ${NO_3}^-$, $K^+$, and $Cl^-$ at day and night showed mostly bimodal size distributions, peaking at the size range of $0.32-0.55{\mu}m$(condensation mode) and $3.1-6.2{\mu}m$(coarse mode), respectively, with a predominant condensation mode and a minor coarse mode. While ${NH_4}^+$ and ${SO_4}^{2-}$ showed unimodal size distributions which peaked between 0.32 and $0.55{\mu}m$. WSOC was enriched into nuclei mode particles(< $0.1{\mu}m$) based on the WSOC-to-mass and WSOC-to-water soluble species ratios. The sources and formation mechanisms of WSOC were inferred in reference to the size distribution characteristics of inorganic species(${SO_4}^{2-}$, ${NO_3}^-$, $K^+$, $Ca^{2+}$, $Na^+$, and $Cl^-$) and carbon monoxide. Nuclei mode WSOC was likely associated with primary combustion sources during daytime and nighttime. Among significant sources contributing to the condensation mode WSOC were homogeneous gas-phase oxidation of VOCs, primary combustion emissions, and fresh(or slightly aged) biomass burning aerosols. The droplet mode WSOC could be attributed to aqueous oxidation of VOCs in clouds, cloud-processed biomass burning aerosols, and small contributions from primary combustion sources. From the correlations between WSOC and soil-related particles, and between WSOC and sea-salt particles, it is suggested that the coarse mode WSOC during daytime is likely to condense on the soil-related particles($K^+$ and $Ca^{2+}$), while the WSOC in the coarse fraction during nighttime is likely associated with the sea-salt particles($Na^+$).

• Progress in Superconductivity and Cryogenics
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• v.14 no.4
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• pp.50-53
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• 2012

This paper describes experimental study on GM-type pulse tube refrigerator (PTR). In a PTR, the pulse tube is only filled with working gas and there exists secondary flow due to a large temperature difference between cold-end and warm-end. The stability of secondary flow is affected by orientation of cold-head and thus, the cooling performance is deteriorated by gas mixing due to secondary flow. In this study, a single stage GM-type pulse tube refrigerator is fabricated and tested. The cooing performance of the fabricated PTR is measured as varying cold-head orientation angle and the results are used as reference data. Then, we divided interior space of pulse tube into three segments, and fixed the various size of screen mesh at interface of each segment to suppress the performance degradation due to secondary flow. For various configuration of pulse tube, no-load test and heat load test are carried out with the fixed experimental condition of charging pressure, operating frequency and orifice valve turns. From experimental results, the fine screen mesh shows the effective suppression of performance degradation for the large orientation angle, but the use of screen mesh cause the loss of cooling capacity rather than the case of no insertion into pulse tube. It should be compromised whether the use of screen mesh in consideration of the installation limitation of a GM-type pulse tube refrigerator.

• Journal of Pharmaceutical Investigation
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• v.27 no.2
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• pp.119-123
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• 1997

The physicochemical and structural properties of new capsaicin derivative, DA-5018, were examined. The reference standard of this compound was obtained by the recrystallization. A method for the determination of the dissociation constant of the compound is described. pH-solubility and distribution coefficient were determined by chromatographic method. Fundamental properties on thermal behaviors were investigated by TG, DTA and DSC. Structural analysis based on spectroscopic method coincided with the chemical structure of DA-5018. Approximate dissociation constant of the compound determined by UV spectral method was 9.35. Solubilities and partition coefficients in various pH buffer solution appeared pH-dependency. No crystal transition or further transition was found in the thermal analysis. This compound showed good stability, but pH 13 buffer and acetone made some degradative products.

• Journal of Korean society of Dental Hygiene
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• v.8 no.1
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• pp.1-12
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• 2008

I investigated the situation of self-realization for oral malodor and real occurrence of it and researched the situation of coincidence by self-administrated questionnaire and real oral malodor of dental hygiene students in Kyeonggi province and Kyeongbuk province to use as a reference data on prevention and treatment of oral malodor. The obtained results were as follows: 1. Concerning the grade of the subjective symptom of oral odor, a little bit oral malodor was the highest by reaching 77.6%, and no oral malodor was 20%. 2. The time when one feels the oral malodor highest was revealed immediately after awakening from the sleep by running up to 88.2%. 3. Concerning the extent of aversion during the occurrence of oral malodor from other people, 57.6% expressed as unpleasant, and 3.5% showed no aversion. 4. Concerning the intention to participate in the prevention program against the oral malodor, 51.8% had intention of it. 5. Hydrogen sulfide 7.61V19.30, methyl mercaptan 9.53V67.90, dimethyl sulfide 58.31V121.37(pF0.05) marked as causing factors in the 132 respondents who answered that they had a little bit oral malodor in comparison with the grade of subjective symptom and the measurement of actual oral malodor. As the above-mentioned results were obtained by limited subjects, the more diversified and precise comparative study is considered to be needed through the classification of various levels of research subjects.

• Archives of Craniofacial Surgery
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• v.12 no.1
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• pp.6-11
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• 2011

Purpose: The cephalic index (CI) is used to classify the head and every race has its unique characteristics. Previous studies published in Korea were limited to demonstrating the periodical change of the CI. This study was done to determine the CI change in 0 to 20 year-old Koreans by sex and age. Methods: The measurement was done on 1,222 Koreans ranging from 0 to 20 years of age, randomly selected from 2,156 who were diagnosed with simple concussion, had no other diseases or anomalies, and took cephalographs from January, 2000 to July, 2008. The files were obtained from $Marosis^{(R)}$ and then photogrammetry was done by $Photoshop^{(R)}$. To standardize the cephalograph, the Frankfort horizontal line was selected as the reference line on lateral view and the line connecting both lateral-orbitales on AP view. The maximal length was obtained from the lateral cephalograph and the maximal breadth from the AP cephalograph. Results: The CI showed no difference by sex (p=0.4848). The CI and age showed negative correlation (p<0.0001). Analyzed separately by the male and the female, the CI showed statistical significance in the male (p<0.0001), but not in the female (p=0.4741) group. Comparing the CI above the age of 11, the CI of the female became greater than that of the male. Conclusion: This study contributes to the standardization of CI measurement and the authors were able to obtain the average CI by age. We concluded that the CI decreased according to age and most Koreans belonged to barchycephalic or hyperbrachycephalic.

• Journal of Korean Medical Science
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• v.33 no.52
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• pp.337.1-337.14
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• 2018

Background: Mitochondrial heteroplasmy, the co-existence of different mitochondrial polymorphisms within an individual, has various forensic and clinical implications. But there is still no guideline on the application of massively parallel sequencing (MPS) in heteroplasmy detection. We present here some critical issues that should be considered in heteroplasmy studies using MPS. Methods: Among five samples with known innate heteroplasmies, two pairs of mixture were generated for artificial heteroplasmies with target minor allele frequencies (MAFs) ranging from 50% to 1%. Each sample was amplified by two-amplicon method and sequenced by Ion Torrent system. The outcomes of two different analysis tools, Torrent Suite Variant Caller (TVC) and mtDNA-Server (mDS), were compared. Results: All the innate heteroplasmies were detected correctly by both analysis tools. Average MAFs of artificial heteroplasmies correlated well to the target values. The detection rates were almost 90% for high-level heteroplasmies, but decreased for low-level heteroplasmies. TVC generally showed lower detection rates than mDS, which seems to be due to their own computation algorithms which drop out some reference-dominant heteroplasmies. Meanwhile, mDS reported several unintended low-level heteroplasmies which were suggested as nuclear mitochondrial DNA sequences. The average coverage depth of each sample placed on the same chip showed considerable variation. The increase of coverage depth had no effect on the detection rates. Conclusion: In addition to the general accuracy of the MPS application on detecting heteroplasmy, our study indicates that the understanding of the nature of mitochondrial DNA and analysis algorithm would be crucial for appropriate interpretation of MPS results.

• Cross-Cultural Studies
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• v.36
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• pp.123-147
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• 2014

The purpose of this essay is three-fold: to trace the genealogy of the Korean musical, which ever since its inception in the 1960s has been seeking to modernize Korean theater with Broadway as a constant role model; to investigate how the national and the global conflict and are conflated in the form of the Korean musical in the process of its (dis)identification with Broadway; and to examine how its intercultural translations reveal and reflect the dilemma and ambivalence posed by globalization in our era. Drawing on Richard Dyer's signature article Entertainment and Utopia, I analyze how the Korean musical manifests and conduits competing utopian impulses of Korean/Global audiences. I also attempt to problematize the formulaic notion of Broadway musicalsthe Superior Other!which implies a global hegemony that does not, in fact, exist because the boundary between the global and the local as well as the power dynamics of global culture are not fixed but constantly moving and changing. Today's musical scene in Korea shows interesting reversals from the 1990s, when Korean producers were eager to debut on Broadway and impress American audiences. Korean producers no longer look up to Broadway as a final destination; instead they want to make Seoul a new Broadway. They import Broadway musicals and turn them into Korean shows. The glamor of Broadway is no longer the main attraction of musicals in Korea. What young audiences look for most is the glamor of K-pop idols and utopian feelings of abundance, energy, intensity, transparency and community, which they can experience live in the musical with their favorite stars right in front of their eyes. In conclusion, I delve into the complex dynamics of recent Korean musicals with Thomas Friedman's theory of Globalization 3.0 as reference. The binary formula of Global/America versus Local/Korea cannot be applied to the dynamic and intercultural musical scene of today. Globalization is not a uniform phenomenon but rather a twofold (multifold) process of global domination and dissemination, in which the global and the local conflict and are conflated constantly. As this study tries to illuminate, the Korean musical has evolved in a huge net of interdependences between the global and the local with a range of sources, powers and influences.

• Journal of the Korea Convergence Society
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• v.10 no.11
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• pp.23-31
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• 2019

With the advent of the era of mass tourism in China and people's yearning for a better life, the demand for family tourism is increasing. This paper adds the filial piety concept variable to the original model based on the theory of planned behavior (TPB). It tests the influence mechanism of attitude, subjective norm, perceived behavior control and filial piety on the intention of family tourism behavior. The results show that； Attitude and subjective norms have significant influence on the intention of family tourism behavior; Perceptual behavior control has no significant influence on the intention of family tourism behavior; Mutual filial piety has a significant impact on family tourism behavior and authoritative filial piety has no significant effect on family tourism decision-making behavior. This conclusion expands the application boundary of the theory of planned behavior in the study of family tourism behavior intentions, and provides application reference for tourists and tourism enterprises.