• Journal of Periodontal and Implant Science
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• v.46 no.3
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• pp.152-165
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• 2016

Purpose: This study investigated the effects of bone density and crestal cortical bone thickness at the implant-placement site on micromotion (relative displacement between the implant and bone) and the peri-implant bone strain distribution under immediate-loading conditions. Methods: A three-dimensional finite element model of the posterior mandible with an implant was constructed. Various bone parameters were simulated, including low or high cancellous bone density, low or high crestal cortical bone density, and crestal cortical bone thicknesses ranging from 0.5 to 2.5 mm. Delayed- and immediate-loading conditions were simulated. A buccolingual oblique load of 200 N was applied to the top of the abutment. Results: The maximum extent of micromotion was approximately $100{\mu}m$ in the low-density cancellous bone models, whereas it was under $30{\mu}m$ in the high-density cancellous bone models. Crestal cortical bone thickness significantly affected the maximum micromotion in the low-density cancellous bone models. The minimum principal strain in the peri-implant cortical bone was affected by the density of the crestal cortical bone and cancellous bone to the same degree for both delayed and immediate loading. In the low-density cancellous bone models under immediate loading, the minimum principal strain in the peri-implant cortical bone decreased with an increase in crestal cortical bone thickness. Conclusions: Cancellous bone density may be a critical factor for avoiding excessive micromotion in immediately loaded implants. Crestal cortical bone thickness significantly affected the maximum extent of micromotion and peri-implant bone strain in simulations of low-density cancellous bone under immediate loading.

• Journal of Radiation Protection and Research
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• v.27 no.2
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• pp.77-80
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• 2002

A more practice approach for the determination of monetary values of the unit collective dose for intervention against long-term exposure following a nuclear accident was proposed. In addition, she monetary values of the unit collective dose estimated from the proposed approach were compared with those estimated from the previous model, which are derived from assumptions of routine exposure and the same values are applied in a nuclear accident without modification, using Korean economic data. The monetary values based on the proposed approach showed a distinct difference depending on inequity in the distribution of individual doses. The discounting rate was also an important factor in determination of monetary values of the unit collective dose.

• Journal of The Korean Astronomical Society
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• v.41 no.6
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• pp.173-180
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• 2008

Using the MHD coronal seismology technique, we estimated the magnetic field for three spicules observed in 2008 June. For this study, we used the high resolution Ca II H line ($3968.5\;{\AA}$) images observed by the Hinode SOT and considered a vertical thin flux tube as a spicule model. To our knowledge, this is the first attempt to estimate the spicule magnetic field using the Hinode observation. From the observed oscillation properties, we determined the periods, amplitudes, minimum wavelengths, and wave speeds. We interpreted the observed oscillations as MHD kink waves propagating through a vertical thin flux tube embedded in a uniform field environment. Then we estimated spicule magnetic field assuming spicule densities. Major results from this study are as follows : (1) we observed three oscillating spicules having durations of 5-7 minutes, oscillating periods of 2-3 minutes, and transverse displacements of 700-1000 km. (2) The estimated magnetic field in spicules is about 10-18 G for lower density limit and about 43-76 G for upper density limit. (3) In this analysis, we can estimate the minimum wavelength of the oscillations, such as 60000 km, 56000 km, and 45000 km. This may be due to the much longer wavelength comparing with the height of spicules. (4) In the first event occurred on 2008 June 03, the oscillation existed during limited time (about 250 s). This means that the oscillation may be triggered by an impulsive mechanism (like low atmospheric reconnection), not continuous. Being compared with the ground-based observations of spicule oscillations, our observation indicates quite different one, i.e., more than one order longer in wavelength, a factor of 3-4 larger in wave speed, and 2-3 times longer in period.

• Tuberculosis and Respiratory Diseases
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• v.78 no.3
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• pp.239-245
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• 2015

Background: Chronic obstructive pulmonary disease is characterized by emphysema, chronic bronchitis, and small airway remodeling. The alveolar destruction associated with emphysema cannot be repaired by current clinical practices. Stem cell therapy has been successfully used in animal models of cigarette smoke- and elastase-induced emphysema. However, the optimal dose of mesenchymal stem cells (MSCs) for the most effective therapy has not yet been determined. It is vital to determine the optimal dose of MSCs for clinical application in emphysema cases. Methods: In the present study, we evaluated the therapeutic effects of various doses of MSCs on elastase-induced emphysema in mice. When 3 different doses of MSCs were intravenously injected into mice treated with elastase, only $5{\times}10^4$ MSCs showed a significant effect on the emphysematous mouse lung. We also identified action mechanisms of MSCs based on apoptosis, lung regeneration, and protease/antiprotease imbalance. Results: The MSCs were not related with caspase-3/7 dependent apoptosis. But activity of matrix metalloproteinase 9 increased by emphysematous lung was decreased by intravenously injected MSCs. Vascular endothelial growth factor were also increased in lung from MSC injected mice, as compared to un-injected mice. Conclusion: This is the first study on the optimal dose of MSCs as a therapeutic candidate. This data may provide important basic data for determining dosage in clinical application of MSCs in emphysema patients.

• Research in Community and Public Health Nursing
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• v.27 no.4
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• pp.370-379
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• 2016

Purpose: The aim of this study was to evaluate the level of self-care adherence in the elderly with diabetes mellitus (DM) who have lived alone, and to investigate the association between health literacy, diabetic knowledge and self-care adherence. Methods: Descriptive research using the cross-sectional approach was conducted. Data was collected by using a convenience sampling of 201 participants who aged sixty-five years old or more and have lived alone. Statistical analysis was conducted by using an independent t-test, one-way ANOVA, $Scheff{\acute{e}}$ test, Pearson correlation coefficient and stepwise multiple regression analysis. Results: Mean scores of health literacy, diabetic knowledge and adherence of self-care were $4.41{\pm}3.54$ points out of a possible $12, 6.22{\pm}2.55$ points out of a possible $15, 58.56{\pm}17.28$ points out of a possible 112, respectively. Adherence of self-care showed a statistical association with health literacy (r=.26, p<.001) and diabetic knowledge (r=.30, p<.001). Statistically significant factors in the regression model were monthly income, diabetic knowledge and exercise. Conclusion: The level of self-care adherence in the elderly with diabetes living alone was relatively low. Diabetic knowledge was an important factor to improve the level of self-care adherence for the elderly with diabetes living alone.

• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.293-298
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• 2017

The purpose of this study was to analyze the risk factors of depression in elementary school students in Korea. The subjects of the study were 23,291 elementary school students (12,016 male, 11,275 female) aged 9 to 12 years. Dependent variable was defined as experience of depression. Explanatory variables were included as sex, residential areas, social discrimination experience, experience of school violence for the past year, experience of Korean language education, experience of using multicultural family support center, reading to Korean, speaking to Korean, and writing to Korean, listening to Korean. In the RBF neural network analysis, experience of Korean education, experience of school violence, experience of Korean social discrimination, level of Korean reading were significantly associated with depression in elementary school students. In order to prevent depression in multicultural children, priority attention and counseling are needed for the group whose level of Korean reading is low.

• Archives of Craniofacial Surgery
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• v.18 no.1
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• pp.9-15
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• 2017

Background: Relaxin is a transforming growth factor ${\beta}1$ antagonist. To determine the effects of relaxin on scar reduction, we investigated the scar remodeling process by injecting relaxin-expressing adenoviruses using a pig scar model. Methods: Scars with full thickness were generated on the backs of Yorkshire pigs. Scars were divided into two groups (relaxin [RLX] and Control). Adenoviruses were injected into the RLX (expressing relaxin) and Control (not expressing relaxin) groups. Changes in the surface areas, color index and pliability of scars were compared. Results: Fifty days after treatment, the surface areas of scars decreased, the color of scars was normalized, and the pliability of scars increased in RLX group. Conclusion: Relaxin-expressing adenoviruses improved the surface area, color, and pliability of scars. The mechanism of therapeutic effects on scar formation should be further investigated.

• Journal of Family Resource Management and Policy Review
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• v.17 no.1
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• pp.139-158
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• 2013

This research aimed to determine how a combined yoga and tea meditation program would affect the happiness of adolescents. The investigation was conducted over a total of 11 sessions held twice a week with 15 female middle-school students. Each session lasted 90 min and comprised preparation for 5 min, Hatha yoga for 50 min, tea meditation for 15 min, the expression of feelings for 15 min, and 5 min were allocated to finishing the program and announcing the next session time. A t-test was performed before and after the program to analyze the effects of the program. A goodness of fit test, which is related to the improvement of happiness, was done through a path analysis. As a result, we were able to determine meaningful changes in the t-test scores of happiness, stress, and quality of life. The scores of mindfulness, physical self-concept, and self efficiency changed positively, but meaningful changes were not shown. To derive a final conclusion, we verified the mediator effect with respect to happiness through a structural model. Consequently, physical self-concept was activated as a promoter for improving self-efficiency and mindfulness. Mindfulness was the key factor that improved the happiness of the adolescent subjects.

• Journal of Family Resource Management and Policy Review
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• v.22 no.1
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• pp.79-98
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• 2018

The purpose of this study was to analyze the influence of a married adult on child-toparent and on parent-to-child financial supports. The data, derived from Korean General Social Survey(KGSS) was obtained from the Survey Research Center at Sung Kyun Kwan University. The samples included 367 married adult children who had more than one living parent. Multiple regression analysis was used to analyze the research model. The findings from the analysis showed that monthly household income had no significant impact on the financial supports that adult children provided to their parents or that the parents provided to their child. The expectation of financial supports from their parents in the future was a important factor that affected the level of female and male children's financial supports that they received from their parents. The level of instrumental supports from their parents and their parents-in-law did influence the level of financial transfers between them. These results showed that financial transfers between married adult children and their parents differed based on the children's attitude towards the supporting parents, and whether or not the children or parents had alternative resources available to them for financial supports. Moreover, the variation in financial supports and benefits showed complex differences based on the gender of the children, and based on whether the financial support was coming from the respondent's parents or their partner's parents.

• Korean Chemical Engineering Research
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• v.53 no.1
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• pp.64-70
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• 2015

Batch experiment studies were carried out for adsorption of congo red using granular activated carbon with various parameters such as activated carbon dose, pH, initial dye concentration, temperature and contact time. Equilibrium experimental data are fitted to the Langmuir, Freundlich, Temkin and Dubin-Radushkevich isotherm equations. From Freundlich's separation factor (1/n) estimated, adsorption could be employed as effective treatment method for adsorption of congo red from aqueous solution. Base on Temkin constant (B) and Dubinin-Radushkevich constant (E), this adsorption process is physical adsorption. Adsorption kinetics has been tested using pseudo-first order and pseudo second order models. The results followed pseudo second order model with good correlation. Adsorption process of congo red on granular activated carbon was endothermic (${\Delta}H$=42.036 kJ/mol) and was accompanied by decrease in Gibbs free energy (${\Delta}G$=-2.414 to -4.596 kJ/mol) with increasing adsorption temperature.