• The korean journal of orthodontics
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• v.39 no.6
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• pp.393-401
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• 2009

Objective: The purpose of this study was to compare the shear bond strength (SBS) of brackets and microleakage of a tooth-adhesive-bracket complex bonded with a direct and an indirect bonding technique after thermocycling. Methods: Fifty non-carious human premolars were divided into two equal groups. In the direct bonding group a light-cured adhesive and a primer (Transbond XT) was used. In the indirect-bonding group, a light-cured adhesive (Transbond XT) and chemical-cured primer (Sondhi Rapid Set) were used. After polymerization, the teeth were kept in distilled water for 24 hours and thereafter subjected to thermal cycling (500 cycles). For the microleakage evaluation, 10 teeth from each group were further sealed with nail varnish, stained with 0.5% basic fuchsin for 24 hours, and examined under a stereomicroscope. Fifteen teeth from each group were used for SBS testing with the universal testing machine and adhesive remnant index (ARI) evaluation. Data were analyzed using the Mann-Whitney U test, Chi-square test, and Fisher's exact test. Results: There were no statistical differences on SBS and microleakage between the two bonding techniques. The indirect bonding group had a significantly lower ARI score. Bracket failures were obtained between enamel-resin interfaces. Conclusions: The type of bonding technique did not significantly affect the amount of microleakage and SBS.

• Journal of the Korean Vacuum Society
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• v.17 no.1
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• pp.28-33
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• 2008

Lanthanum modified lead zirconate titanate ($Pb_{1.1}La_{0.08}Zr_{0.65}Ti_{0.35}O_3$) thin films were fabricated on indium doped tin oxide (ITO)-coated glass substrate by R.F magnetron sputtering method. The thin films were deposited at $500^{\circ}C$ and post-annealed with various temperature ($550-750^{\circ}C$) by rapid thermal annealing technique. The structure and morphology of the films were characterized with X-ray diffraction (XRD) and atomic force microscopy (AFM) respectively. The hysteresis loops and fatigue properties of thin films were measured by precision material analyzer. As the annealing temperature was increased, the remnant polarization value was increased from $10.6{\mu}C/cm^2$ to $31.4{\mu}C/cm^2$, and coercive field was reduced from 79.9 kV/cm to 60.9 kV/cm. As a result of polarization endurance analysis, the remnant polarization of PLZT thin films annealed at $700^{\circ}C$ was decreased 15% after $10^9$ switching cycles using 1MHz square wave form at ${\pm}5V$.

• Korean Journal of Materials Research
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• v.12 no.12
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• pp.962-966
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• 2002

The $SrBi_2$$Nb_2$$O_{9}$ (SBN) thin films were deposited with $SrNb_2$$O_{6}$ / (SNO) and $Bi_2$$O_3$ targets by co-sputtering method. For the growth of SBN thin films, we adopted the various power ratios of two targets; the power ratios of the SNO target to $Bi_2$$O_3$ target were 100 W : 20 W, 100 W : 25 W, and 100 W : 30 W during sputtering the SBN films. We found that the electrical properties of SBN films were greatly dependent on Bi content in films. The $Bi_2$Pt and $Bi_2$$O_3$ phase as second phases occurred at the films with excess Bi content greater than 2.4, resulting in poor ferroelectric properties. The best growth condition of the SBN films was obtained at the power ratio of 100 W : 25 W for the two targets. At this condition, the crystallinity and electrical properties of the films were improved at even low annealing temperature as $700^{\circ}C$ for 1h in oxygen ambient and the Sr, Bi and Nb component in the SBN films were about 0.9, 2.4, and 1.8 respectively. From the P-E and I-V curves for the specimen, the remnant polarization value ($2P_{r}$) of the SBN films was obtained about 6 $\mu$C/c $m^2$ at 250 kV/cm and the leakage current density of this thin film was $2.45$\times$10^{-7}$ $A/cm^2$ at an applied voltage of 3 V.V.

• Journal of Chest Surgery
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• v.41 no.1
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• pp.49-54
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• 2008

Background: Aortic diseases tend to involve the entire aorta. Hence, there is the constant possibility of the need for a secondary operation at the remnant aorta. This study analyzed our cases of secondary aortic surgery in order to determine its characteristics and problems. Material and Method: Between April 2003 and June 2007, 12 patients (6 male and 6 female) underwent thoracoabdominal aortic replacement as a secondary aortic operation. Their clinical courses were analyzed. Four of the patients underwent lower thoracobadominal aortic replacement under the normothermic femorofemoral bypass, and the others underwent an entire thoracobdominal aortic replacement under deep hypothermic circulatory arrest. Result: There was no death or paraplegia. As local complications, there were 3 cases of wound infection and 2 cases of an immediate reoperation caused by bleeding and one case of delayed wound. revision for a contaminated perigraft hematoma. As a systemic complication, there was one case of renal insufficiency, which required hemodialysis and one case of respiratory insufficiency that needed prolonged ventilator care. The mean admission period was $30{\pm}21$ days. All the patients were followed up for $626{\pm}542$ days without reoperation or other problems. Conclusion: Using properly selected patients and a careful approach, thoracoabdominal aortic replacement can be performed safely as a secondary aortic surgery.

• Journal of Conservation Science
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• v.29 no.1
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• pp.69-79
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• 2013

This study aims at identifying the variation of physicochemical properties for galena ore in order to use it in understanding of manufacturing techniques in terms of metallurgical method and smelting or refining process for obtaining lead. The ores in the study obtained from the operating mine have been washed and pre-treated for a test. Metallic lead has been extracted by roasting process. The result displays that galena is still in present in the matt despite of exposure to high temperature, over $1000^{\circ}C$. Nearly $11.1g/cm^3$ specific gravity metallic lead has been collected from the refining test of which aim was to remove the remnant galena and a trace of concentrated silver has been identified at the grain boundary. The result suggests that at least one refining process was essential to acquire high purity metallic lead and cupellation had been executed to remove remnant silver.

• The korean journal of orthodontics
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• v.40 no.5
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• pp.342-348
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• 2010

Objective: The aim of this study was to compare the shear bond strengths (SBS) of orthodontic brackets bonded to enamel with a self-etching primer after bleaching, desensitizer application and combined treatment. Methods: Forty-eight premolars were randomly divided into four groups, each with n = 12 premolar samples. The four groups were; Group1: 15% hydrogen-peroxide office bleaching agent (Illumin$\acute{e}$ Office-IO), Group 2: IO + BisBlock Oxalate Dentin-Desensitizer, Group 3: Bis Block Oxalate Dentin-Desensitizer, Group 4: No treatment (control). Twenty-four hours after bonding, the specimens were tested in SBS at a crosshead speed of 5 mm/min until the brackets debonded. The failure mode of the brackets was determined by a modified adhesive remnant index. Results: Bleaching, bleaching and desensitizer treatment, and desensitizer treatment alone all significantly reduced SBS of the orthodontic brackets ($p$ = 0.001). No statistically significant difference was found between Group 1, Group 2 and Group 3 (Group 1-Group 2, $p$ = 0.564; Group 1-Group 3, $p$ = 0.371; Group 2-Group 3, $p$ = 0.133). The predominant mode of failure for the treatment groups (Group1, Group 2 and Group 3) was at the enamel-adhesive interface leaving 100% of the adhesive on the bracket base. Conclusions: Bleaching and desensitizer treatment should be delayed until the completion of orthodontic treatment.

• Journal of Gastric Cancer
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• v.7 no.1
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• pp.42-46
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• 2007

Usually in the subtotal gastrectomy, the left and the right gastric arteries, as well as the left and the right gastroepiploic arteries are ligated. Thus, to avoid a blue stomach surgeons preserve the spleen and the short gastric arteries. When a radical subtotal gastrectomy with splenectomy is performed, meticulous caution is necessary; otherwise, the subtotal gastrectomy might have to be changed to a total gastrectomy to prevent a blue stomach. We report the case of a 67-year-old woman who had distal stomach cancer with a splenic solitary mass, for which splenic meatastasis could be excluded. We planned and performed a laparoscopy-assisted radical subtotal gastrectomy with splenectomy as the diagnostic and therapeutic option. In this case, to avoid a remnant stomach infarction or total gastrectomy we saved the left gastric artery and vein with clearing perivascular soft tissue, lymphatics, and lymph nodes. Thus the radical therapeutic goal was reached, and serious complications were avoided.

• Tuberculosis and Respiratory Diseases
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• v.67 no.5
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• pp.422-429
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• 2009

Background: The discomfort caused by chronic cough, that is persistent for more than 3 weeks, causes a number of patients to seek medical attention. However, the underlying disorder often remains undetermined despite thorough examinations, and is considered to be idiopathic. This study compared the efficacy of inhaled corticosteroid with conventional cough suppressants on chronic idiopathic cough. Methods: Eligible patients with chronic idiopathic cough were randomly assigned to either the inhaled fluticasone group or the codeine plus levodropropizine oral administration group. The subjects in each group took their planned medication for 2 weeks. After the trial, comparative analyses of outcomes were performed in terms of the remnant cough (%) at the end of treatment, drug compliance, and adverse drug events. Results: Seventy-seven patients were enrolled in this randomized trial; 38 to the inhaled fluticasone group and 39 to the codeine plus levodropropizine group. The remnant cough was 41.0${\pm}$35.8% in the inhaled fluticasone group, and 32.4${\pm}$32.0% in the codeine+levodropropizine group (p=0.288). Drug compliance was 95.4${\pm}$7.4% and 81.8${\pm}$18.6% in the inhaled fluticasone and the codeine+levodropropizine group, respectively (p<0.001). Nine patients had adverse drug events in the codeine+levodropropizine group compared to one in the inhaled fluticasone group (p<0.001). Conclusion: Short-term inhaled corticosteroid is not inferior to conventional antitussive agents in controlling chronic idiopathic cough without significant adverse events.

• The Journal of Korean Obstetrics and Gynecology
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• v.30 no.3
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• pp.1-19
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• 2017

Objectives: The object of this study is to observe the possible ameliorating effects of Nokyongdaebo-tang (NYDBT) on the experimental subacute hemorrhagic anemia (SHA) in rats. Methods: In the present study, SHA in rats was induced by exsanguinations from orbital plexus, and ameliorating effects of NYDBT was observed based on the changes of body and hematopoietic organ (spleen, liver and femur) weights, red blood cell (RBC) related hematological values, smear cytology, histopathological changes and immunohistochemistrical analysis of hematopoietic stem cells in the femur bone marrow, liver and spleen. In addition, the gastrointestinal motility and the surface mucosa thicknesses of remnant fecal pellets in the colon lumen, mucosa thicknesses and the mucous producing cell numbers in the colonic mucosa were analyzed to observe the digestive disorders, especially on the constipation, the major discomfort problems in iron supplement. Results: SHA related abnormal anemic signs were markedly and dose-dependently inhibited by oral administration of NYDBT 500, 250 and 125 mg/kg in a condition of this experiment. In addition, no meaningful changes on the gastrointestinal motilities and mucous component on the colon and remnant feces were noticed in all three different dosages of NYDBT treated rats as compared with intact vehicle and SHA control rats in this study. Conclusions: It, therefore, is expected that NYDBT will be promising as a novel alternative hematopoietic and therapeutic agent for anemia.

• Journal of the Korean Orthopaedic Association
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• v.54 no.2
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• pp.150-156
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• 2019

Purpose: This study examined the diagnostic accuracy of an imaging study to find the factors that affect the presence of residual tumors after an unplanned excision of sarcomas. Materials and Methods: Ninety-eight patients, who underwent a re-excision after unplanned surgery between January 2008 and December 2014, were enrolled in this study. Magnetic resonance imaging (MRI) was performed before reoperation in all patients. Positron emission tomography (PET)-computed tomography was performed on 54 patients. A wide re-excision and histology diagnosis were performed in all cases. The clinical variables were evaluated using univariate logistic regression and multivariate logistic regression. Results: The presence of a deep-seated tumor increases the risk of remnant tumors (odds ratio: 3.21, p=0.02, 95% confidence interval: 1.25-8.30). The sensitivity for detecting residual tumors is high in MRI (sensitivity 0.79). Conclusion: Deep-seated tumors have a significantly higher risk of remnant tumors. Because the negative predictive value of MRI and PET scans is very low, reoperation should be performed regardless of a negative result.