• Journal of radiological science and technology
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• v.31 no.4
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• pp.401-406
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• 2008

The aim of this study is to evaluate contra-lateral breast (CLB) surface dose in Field-in-Field (FIF) technique for breast conserving surgery patients. For evaluation of surface dose in FIF technique, we have compared with other techniques, which were open fields (Open), metal wedge (MW), and enhanced dynamic wedge (EDW) techniques under same geometrical condition and prescribed dose. The three dimensional treatment planning system was used for dose optimization. For the verification of dose calculation, measurements using MOSFET detectors with Anderson Rando phantom were performed. The measured points for four different techniques were at the depth of 0cm (epidermis) and 0.5cm bolus (dermis), and spacing toward 2cm, 4cm, 6cm, 8cm, 10cm apart from the edge of tangential medial beam. The dose calculations were done in 0.25cm grid resolution by modified Batho method for inhomogeneity correction. In the planning results, the surface doses were differentiated in the range of $19.6{\sim}36.9%$, $33.2{\sim}138.2%$ for MW, $1.0{\sim}7.9%$, $1.6{\sim}37.4%$ for EDW, and for FIF at the depth of epidermis and dermis as compared to Open respectively. In the measurements, the surface doses were differentiated in the range of $11.1{\sim}71%$, $22.9{\sim}161%$ for MW, $4.1{\sim}15.5%$, $8.2{\sim}37.9%$ for EDW, and 4.9% for FIF at the depth of epidermis and dermis as compared to Open respectively. The surface doses were considered as underestimating in the planning calculation as compared to the measurement with MOSFET detectors. Was concluded as the lowest one among the techniques, even if it was compared with Open method. Our conclusion could be stated that the FIF technique could make the optimum dose distribution in Breast target, while effectively reduce the probability of secondary carcinogenesis due to undesirable scattered radiation to contra-lateral breast.

• Journal of the Korea Concrete Institute
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• v.21 no.3
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• pp.245-253
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• 2009

The importance of chloride ions in the corrosion of steel in concrete has led to the concept for chloride threshold level (CTL). The CTL can be defined as the content of chlorides at the steel depth that is necessary to sustain local passive film breakdown and hence initiate the corrosion process. Despite the importance of the CTL, due to the uncertainty determining the actual limits in various environments for chloride-induced corrosion, conservative values such as 0.4% by weight of cement or 1.2 kg in 1 $m^3$ concrete have been used in predicting the corrosion-free service life of reinforced concrete structures. The paper studies the CTL for blended cement concrete by comparing the resistance of cementitious binder to the onset of chloride-induced corrosion of steel. Mortar specimens were cast with centrally located steel rebar of 10 mm in diameter using cementitious mortars with ordinary Portland cement (OPC) and mixed mortars replaced with 30% pulverized fuel ash (PFA), 60% ground granulated blast furnace slag (GGBS) and 10% silica fume (SF), respectively, at 0.4 of a free W/B ratio. Chlorides were admixed in mixing water ranging 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 2.5 and 3.0% by weight of binder(Based on $C1^-$). Specimens were curd 28 days at the room temperature, wrapped in polyethylene film to avoid leaching out of chloride and hydroxyl ions. Then the corrosion rate was measured using the polarization resistance method and the order of CTL for binder was determined. Thus, CTL of OPC, 60%GGBS, 30%PFA and 10%SF were determined by 1.6%, 0.45%, 0.8% and 2.15%, respectively.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.359-367
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• 2012

This study was to evaluate the influence of dental caries prevention-related concerned and perceived in Korean adults and oral health behavior of their first child if they had children. A cross-sectional study in 1,014 adults over 19 years old were conducted in Korean adults, asked to answer a computer-assisted telephone interview regarding their oral health-related knowledge, behavior, concerned of caries prevention and child's behaviors such as frequencies of tooth brushing, chewing the xylitol gum and dental checkup. The statistical analysis was done by using the SPSS 19.0 program (IBM Co., Armonk, NY, USA). Awareness of caries prevention in the female than male, 40~49 years old age group was higher. Parents of school-age children were higher level of awareness of the dental caries prevention than other group. As knowledge and behavior of dental caries prevention were higher, the child's conduct regular oral health checkups, fluoride topical application and dental sealant was significantly higher. The higher the concerned of caries preventive, the intention of oral health behaviors and child's oral health behaviors was more increased. Awareness of caries prevention had effect on the perception of the impact of the child's oral health behaviors.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.4
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• pp.253-268
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• 1993

The author studied on the 109 cases of ameloblastoma which had been diagnosed with biopsy during the period of 1962 to 1992 at the Kyungpook National University Hospital, Kyemyung University Hospital, Youngnam University Hospital, Catholic Medical School Hospital, Pusan National University and Maryknoll Hospital. This study contains the statistical analysis of the treatment method according to the clinicopathological findings such as sex, age, location, chief complaints, duration, radiographic findings, size and recurrence. The results were as follows : 1. The incidence rate was 59.7% in male and 40.3% in female. 2. At the time of diagnosis, the age of the patients ranged from 9 to 69 years(average 31.4years). The cases of 72.4% were in the 2nd, 3rd, and 4th decades of life. 3. The majority of cases occurred in the mandible 88.9%, especially in the mandiblar angle area 57.8%. 4. The most prevalent chief complaints was swelling 58.7%. 5. As regards duration, the cases less than 1 year appeared 49.5% and average duration is 31.34months. 6. Unilocular type showed 43.1% and multilocular type appeared 56.9%. 7. Conservative treatment was performed 39.4% and radical treatment was employed 60.6%. 8. There were variations of lesional sizes between 2.0cm and 15cm(average 6.26cm). 9. The recurrence rate is 29.4%. 10. The frequency of treatment was not in association with sexes, locations, chief complaints and sizes. 11. Radical treatment was performed more frequently in cases of older age group(above 20 years old), multilocular cases, above average duration(31.34 months) group and recurrent cases (P<0.05).

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.4
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• pp.294-300
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• 2015

Purpose: The purpose of this study was to measure the color of low viscosity bulk-fill resin with a capping layer and to compare it with the color of microhybrid composite resin. Materials and Methods: A low viscosity bulk-fill resin (SDR) and microhybrid composite resin of shade A2 (A2) or A3 (A3) were fabricated to 4 mm thickness and light cured for 20 seconds. CIE $L^*a^*b^*$ values of the resin specimens were measured with a colorimeter. Then shade A2 and A3 microhybrid composite resin was capped over low viscosity bulk-fill resins in 2 mm thickness (SA2, SA3). The resin specimens were light cured for 20 seconds and the color was measured and analyzed (n = 10). Color differences (${\Delta}E$) between SA2 and A2, SA3 and A3 were also calculated. Results: $L^*$ value was highest in SDR followed by SA2 and SA3. $L^*$ value of A2 and A3 was the lowest. $a^*$ value was lowest in SDR followed by SA2 and SA3, and A2 and A3 was the highest. $b^*$ value was lowest in SDR followed by A2 and SA2, and A3 and SA3 was the highest. ${\Delta}E$ between A2 and SA2 (${\Delta}E=3.4$), and that between A3 and SA3 (${\Delta}E=3.1$) was lower than the perceptible color difference threshold of ${\Delta}E=3.7$. Conclusion: ${\Delta}E$ between low viscosity bulk-fill resin with a capping layer and microhybrid resin was lower than the perceptible color difference threshold.

• Tuberculosis and Respiratory Diseases
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• v.61 no.3
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• pp.265-272
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• 2006

Background: Chest wall deformities such as kyphoscoliosis, thoracoplasty, and fibrothorax cause ventilatory insufficiency that can lead to chronic respiratory failure, with recurrent fatal acute respiratory failure(ARF). This study evaluated the frequency and outcome of ARF, the physiologic status, and the long-term prognosis of these patients. Methods: Twenty-nine patients with chest wall disorders, who experienced the first requirement of ventilatory support from ARF were examined. The mortality and recurrence rate of ARF, the pulmonary functions with arterial blood gas analysis, the efficacy of home oxygen therapy, and the long-term survival rate were investigated. Results: 1) The mortality of the first ARF was 24.1%. ARF recurred more than once in 72.7% of the remaining 22 patients, and overall rate of successful weaning was 73.2%. 2) Twenty-two patients who recovered from the first ARF showed a restrictive ventilatory impairment with a mean FVC and TLC of 37.2% and 62.4 % of predicted value, respectively, and a mean $PaCO_{2}$ of 57mmHg. Among the parameters of pulmonaty functions. the FVC(p=0.01) and VC(p=0.02) showed a significant correlation with the $PaCO_{2}$ level. 3) There were no significant differences between the patients treated with conservative medical treatment only and those with additional home oxygen therapy due to significant hypoxemia in the patients with recurrent ARF and the mortality. 4) The 1, 3, 5-year survival rates were 75%, 66%, and 57%, respectively, in the 20 patients who had recovered from the first ARF, excluding the two patients managed by non-invasive nocturnal ventilatory support. Conclusion: These results suggest that active ventilatory support should be provided to patients with ARF and chest wall disorders. However, considering recurrent ARF and weak effect of home oxygen therapy, non-invasive domiciliary ventilation is recommended in those patients with these conditions to achieve a better long-term prognosis.

• Restorative Dentistry and Endodontics
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• v.33 no.1
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• pp.1-8
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• 2008

The purpose of this study was to evaluate the effect of a new resin monomer, filler size and polishing technique on the surface roughness of composite resin restorations using confocal laser scanning microscopy. By adding new methoxylated Bis-GMA (Bis-M-GMA, 2,2-bis[4-(2-methoxy-3-methacryloyloxy propoxy) phenyl] propane) having low viscosity, the content of TEGDMA might be decreased. Three experimental composite resins were made: EX1 (Bis-M-GMA/TEGDMA = 95/5 wt%, 40 nm nanofillers); EX2 (Bis-M-GMA/TEGDMA = 95/5 wt%, 20 nm nanofillers); EX3 (Bis-GMA/TEGDMA = 70/30 wt%, 40 nm nanofillers). Filtek Z250 was used as a reference. Nine specimens (6 mm in diameter and 2 mm in thickness) for each experimental composite resin and Filtek Z250 were fabricated in a teflon mold and assigned to three groups. In Mylar strip group, specimens were left undisturbed. In Sof-lex group, specimens were ground with #1000 SiC paper and polished with Sof-lex discs. In DiaPolisher group, specimens were ground with #1000 SiC paper and polished with DiaPolisher polishing points. The Ra (Average roughness), Rq (Root mean square roughness), Rv (Valley roughness), Rp (Peak roughness), Rc (2D roughness) and Sc (3D roughness) values were determined using confocal laser scanning microscopy. The data were statistically analyzed by Two-way ANOVA and Tukey multiple comparisons test (p = 0.05). The type of composite resin and polishing technique significantly affected the surface roughness of the composite resin restorations (p < 0.001). EX3 showed the smoothest surface compared to the other composite resins (p < 0.05). Mylar strip resulted in smoother surface than other polishing techniques (p < 0.05). Bis-M-GMA. a new resin monomer having low viscosity, might reduce the amount of diluent, but showed adverse effect on the surface roughness of composite resin restorations.

• Restorative Dentistry and Endodontics
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• v.33 no.1
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• pp.66-75
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• 2008

This study examined the influence of the apical sizes on the sealing ability of a root canal filling. Thirty-six single rooted teeth with a single canal were divided into 3 groups (n = 12) and instrumented with either the $Profile^{(R)}$ or $LightSpeed^{(R)}$ system to achieve three different apical sizes (master apical file [MAF] of #25, #40, or #60). The teeth were filled with gutta perch a using a modified continuous wave technique. The level of microleakage was determined by immersing ten teeth from each group into India ink for 1 week followed by clearing with nitric acid, ethyl-alcohol, and methylsalicylate. The microleakage was measured using vernier calipers. The data was analyzed statistically using Kruskal-Wallis one-way ANOVA and a Student-Newman-Keuls Method. Two teeth from each group were sectioned horizontally at 1, 2, 3 and 4 mm from the apex in order to observe a cross section. The apical size was significantly (p < .05) influenced the level of microleakage. In the Student-Newman-Deuls Method, MAF sizes of #25 and #40; and MAF sizes of #25 and #60, respectively showed a statistically significant difference. There was no significant difference between #40 and #60. In most cross sections, oval-shaped canals were observed, and the irregularity of the internal surface increased with decreasing apical size. There was also an increase in the area of recess, which is the area where the canal space is not filled with either gutta-percha or sealer. When the root canals are filled using a modified continuous wave technique, canal filling with more consistent and predictable outcome may be expected as the apical preparation size is increased.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.6
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• pp.990-1001
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• 2009

The purpose of this study was to investigate the effect of perceiver's gender, clothing, and hairstyle on the visual evaluation of men's professionalism and preference. A quasi-experimental method by questionnaire was used. The experimental design was a $2\times8\times2$ (perceiver's gender $\times$ clothing $\times$ hairstyle) factorial design by 3 independent variables. The stimuli were 16 photographs of a man in his twenties. The upper clothing of the man included tailored collar jackets in beige and dark blue colors, and jumpers and sweaters in beige, dark blue, and red colors. The lower clothing of the men included jean pants. Two types of the hairstyles included short hair and medium length hair. The subjects were 208 men and 223 women in Seoul, Korea. Wearing a beige sweater with jean pants was evaluated high in intellectual image, a red jumper was perceived low in intellectual image, and a beige tailored collar jacket was evaluated low in potent image. Men's short hairstyle was evaluated to be more professional than the medium length hair. Male perceivers liked short hair more than medium length hair, but female perceivers evaluated both hairstyles similarly. In the case of women, the preferences of tailored collared jacket and soutien collared jumper were similar, but jumper was preferred to jacket in the case of men. Male perceivers showed more positive feedback towards jean pants with soutien collared jumper than jeans with tailored collared jacket, which indicated that men showed more conservative attitude towards the outfit than women. The man who was wearing a jumper with short hair was evaluated positively and the man who was wearing a jacket with medium length hair was evaluated negatively when the attires were coordinated with jean pants. In conclusion, medium length hairstyle with a beige jacket and short hairstyle with a red sweater were evaluated as professional image; and the results indicated that clothing and hairstyle interact with each other and influence the evaluation of professionalism.

• Journal of Life Science
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• v.18 no.2
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• pp.264-272
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• 2008

The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Acanthogobius hasta were characterized by biochemical, immunochemical and kinetic methods. The activities of LDH in skeletal muscle and eye tissues were 65.30 and 53.25 units, but LDH activities in heart and liver tissues were very low. LDH/CS (EC 4.1.3.7, citrate synthase) in skeletal muscle was the highest as 22.29. Specific activities of LDH in brain, eye and skeletal muscle were 56.45, 38.04 and 11.0 units/mg, respectively. The LDH isozymes in tissues were separated by polyacrylamide gel electrophoresis after immunoprecipitation with antiserum against $A_4,\;B_4$ eye-specific $C_4$ and liver-specific $C_4$. LDH $AC_4$ isozymes were detected predominantly in skeletal muscle, brain and eye tissues, and $B_4$ isozyme was detected in heart. Anodal eye-specific $C_4$ and cathodal liver-specific $C_4$ were coexpressed in A. hasta. The eye-specific $C_4$ isozyme showed higher activity in eye tissue, but liver-specific $C_4$ isozyme showed lower activity in liver. As a result, one part of molecular structures in $A_4\;and\;C_4,\;A_4\;and\;B_4$, and eye-specific $C_4$ and liver-specific $C_4$ were similar, but in $B_4\;and\;C_4$ were different with each other. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The LDH $A_4$ isozyme of skeletal muscle was purified in the fraction from elution with NAD+ containing buffer of affinity chromatography and eye-specific $C_4$ isozyme was eluted right after $A_4$, so the structure of eye-specific $C_4$ isozyme is similar to $A_4$. And LDH activity remained 35.22-43.47% as a result of the inhibition by pyruvate, the Michaelis-Menten constant values for pyruvate was 0.080-0.098 mM, and Vmax were 153.85 units, 35.09 units in skeletal muscle and eye, respectively. Also the $B_4$ isozyme was the thermo-stablest and $C_4$ was stabler than $A_4$ isozyme. The optimum pH of LDH was 6.5. The results mentioned above indicate that isozymes in tissues showed the properties between LDH $A_4\;and\;B_4$ isozyme as A. hasta was adapted to hypoxic conditions. Also LDH seems to function more effectively under anaerobic condition because LDH in skeletal muscle and eye tissues have high affinity for pyruvate.