• The Journal of Korean Academy of Prosthodontics
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• v.35 no.4
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• pp.706-718
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• 1997

Ceramometal crowns are common restorations in fixed prosthodontics because of their casting accuracy, the high strength properties of the metal, and the cosmetic appearance of porcelain. However, deterioration of the initial fit of the metal coping has been observed after the porcelain firing cycle. The distortion due to repeated firing makes it difficult to fit crown margin and elicits microleakage. The major causes of distortion are the residual stress that accumulate during wax-up, casting, cold work and the induced stress caused by the mismatch of porcelain-metal thermal contraction. This study examined the marginal fit changes of metal copings in relation to repeated firing and the effects of heat treatment that reduce the distortion resulted from residual stress. The marginal changes of the copings that were treated with conventional method and those treated with heat before repeated firing, were evaluated. The metal die which represented preparations of a maxillary central incisor was fabricated, and 45 wax patterns were cast with nonprecious metal alloys. The heat treatment of each group was performed as follows. Group 1(control) : Casting - Devesting - Cold work - Firing Group 2 : Casting - Heat treatment - Devesting - Cold work - Firing Group 3 : Casting - Devesting - Cold work - Reinvesting - Heat treatment - Devesting - Firing The copings were fired 3 times. After each firing, the marginal fit changes were measured with inverted metallurgical microscope at the 4 reference points located at labial, lingual, and both proximal surface. Measurements were compared, and statistically analyzed. The results were as follows ; 1. In all groups, the highest value of marginal fit changes of the copings studied were found after the first firing cycle. 2. When the distortion of each experimental group at the first firing cycle were compared, group 1 exhibited the greatest changes($20-27{\mu}m$), followed by group 2($9-13{\mu}m$), and group 3($8-10{\mu}m$). 3. The copings treated with heat before devesting(group 2) revealed significantly smaller marginal fit changes than the copings treated with conventional method(group 1). (p<0.01) 4. The copings treated with heat after reinvesting(group 3) revealed significantly smaller marginal fit changes than the copings treated with conventional method(group 1). (p<0.01) 5. No siginificant differences in marginal fit changes were found between the copings treated with heat before devesting(group 2) and the copings treated with heat after reinvesting(group 3). (p>0.01)

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.803-823
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• 1999

In order to reveal immunopathogenesis of periodontal tissue destruction, it is important to clarify the molecular mechanism of trafficking and retention of activated leukocytes, including monocytes/macrophages. Gingival fibroblasts may be involved in the regulation of inflammatory cell accumulation in the extravascular periodontal connective tissues via cytokine production and surface expression of adhesion molecules. In this study, it was investigated the molecular basis for the adhesive interactions between monocytes and fibroblasts such as peri-odontal ligament fibroblast(PDLF), human gingival fibroblast(HGF), and human dermal fibroblast(HDF). First, it was examined the evidence whether monocyte-fibroblast cell contact may cause signal transduction in fibroblasts. Being directly in contact with fixed human monocyte cell line THP-1, or U937, upregulation of IL-6 production, $TNF-{\alpha}$ mRNA expression and increased cell proliferation could be seen for fibroblasts. IL-6 production induced by monocyte- fibroblast coculture were further increased when fibroblasts had been pretreated with $IFN-{\gamma}$ or $IL-1{\beta}$ , and monocytes with LPS. Next, it was examined the expression of ICAM-1 which has been known to be involved in accumulation and activation of leukocytes in inflammatory diseases such as periodontitis. ICAM-1 was upregulated up to 10-fold on PDLF, HGF, and HDF by exposure to $IFN-{\gamma}$ or $IL-1{\beta}$. Furthermore, anti-ICAM-1 monoclonal antibody clearly blocked cocultureinduced IL-6 production by fibroblasts, suggesting that $ICAM-1/{\beta}_2$integrin pathway is involved in periodontal fibroblastmonocyte interaction. Overall, these findings provide evidence that periodontal fibroblasts could be involved in the accumulation and retention of monocytes/macrophages in periodontal inflammatory lesion at least in part by ICAM-1 expression. In addition, periodontal fibroblast-monocyte interaction could cause activation signals in fibroblasts intracellularly which result in cytokine production and cell proliferation. Thus, periodontal fibroblasts are speculated to play an important role in immunoregulation and tissue destruction in chronic periodontal diseases by interaction with monocytes/macrophages.

• Archives of Plastic Surgery
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• v.42 no.5
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• pp.572-579
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• 2015

Background Facial rejuvenation can be achieved using a variety of techniques. Since minimally invasive procedures for face lifting have become popular because of their convenience and short operating time, numerous minimally invasive surgical procedures have been developed. In this study, a nonabsorbable polypropylene mesh is introduced as a new face lifting instrument, with the nasolabial fold as the main target area. In this paper, we report the efficacy and safety of a polypropylene mesh in midface rejuvenation. Methods Thirty-three subjects with moderate-to-severe nasolabial folds were enrolled from two medical institutions for a noncomparative single-sample study. A mesh was inserted above the superficial muscular aponeurotic system layer, reaching the nasolabial folds through a temporal scalp incision. After 3 weeks, the temporal end of the mesh was pulled to provide a lifting effect. Then, the mesh was fixed to the deep temporal fascia using nonabsorbable sutures. To evaluate efficacy, we compared the scores on the Wrinkle Severity Rating Scale and a visual analog scale for patient satisfaction between the baseline and 7 weeks postoperatively. In addition, we evaluated safety based on the incidence of adverse events. Results The treatment was deemed effective at improving wrinkles in 23 of 28 cases, and patient satisfaction improved significantly during the study period. There were seven cases of skin or subcutaneous tissue complications, including edema and erythema, but there were no suspected serious adverse events. Conclusions Face lifting using a nonabsorbable mesh can improve nasolabial folds without serious adverse effects. Thus, this technique is safe and effective for midface rejuvenation.

• Archives of Plastic Surgery
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• v.36 no.4
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• pp.385-392
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• 2009

Purpose: In the partial thickness burn management, despite of several advantages, the use of human amniotic membrane has been limited. The authors applied dried bovine amniotic membrane(DBAM) to overcome disadvantages of amniotic membrane for partial thickness burn and compared the effectiveness with cultured allogenic keratinocytes(CAK) that have been recently used for the management of burn. Methods: 16 patients with partial thickness burn, the mean age of 38 ranging 12 to 59 years, between August 2007 and May 2008 were assigned to this study. Either DBAM or CAK was applied, and the secondary dressing was removed on the following day. To compare treatment effect, time for epithelization, Vancouver scar scale and chromameteric results were evaluated. Results: The time for epithelization of DBAM was 10.1 days, that of CAK was 9.1 days, and they were shorter than the previous 2 - 3 weeks. At the follow up Vancouver scar scale was 2.8 for DBAM and 3.0 points for CAK and showed good results. The result of chromameter showed that the $L^*$, $a^*$, and $b^*$ values of the area applied DBAM were 60.1, 13.6, and 13.3, respectively, and the values of the area applied CAK were 60.1, 12.4, and 12.4, respectively. It was found that the skin color of the healed area after burn was darker, the redness was higher, and the yellowness was lower. After dressing, significant side effects were not observed, and in the cases of applying CAK, it was inconvenient as the moving area had to be fixed. Conclusion: With CAK, DBAM has several advantages such as the shortening of the epithelization period, reduction of scar and pigmentation, and convenient application, etc. Thus it is an effective method for the partial thickness burn management.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.1 no.1
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• pp.65-72
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• 2003

Adsorption and desorption characteristics of methyl iodide at high temperature conditions up to 25$0^{\circ}C$ by TEDA-impregnated activated carbon and silver-ion exchanged zeolite(AgX-10), which are used for radioiodine retention in nuclear facility, were experimentally evaluated. In the range of temperature from 3$0^{\circ}C$ to 25$0^{\circ}C$, the adsorption capacity of base activated carbon decreased sharply with increasing temperature but that of TEDA-impregnated activated carbon showed higher value even at high temperature ranges. Especially, the residual amount of methyl iodide after desorption on TEDA-AC represented 30% lower value than that on AgX-10. However, it can be used as an adsorbent for the removal of methyl iodide up to 15$0^{\circ}C$ if it is preventing explosion by Ignition. The breakthrough curves of methyl iodide in the fixed bed packed with AgX-10 uP to 40$0^{\circ}C$ were compared upon the effects of bed temperatures, bed depth and input concentration of methyl iodide. Removal mechanism of methyl iodide on AgX-10 was proposed, based on the analysis of by-product gas generated from adsorption reaction.

• Journal of radiological science and technology
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• v.43 no.3
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• pp.155-159
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• 2020

The purpose of this study is to investigate the effect of posture changes(Anteroposterior projection, Posteroanterior projection) in the plain abdominal examination on breast dose and to examine its clinical usefulness. This study was used a human body phantom and a glass dosimeter. Glass dosimeters were directly inserted from the center and outside of medial and lateral. In this study, the deep dose was measured in the right breast and the surface dose in the left breast. During the abdominal examination, the central X-ray incident point was perpendicularly incident to the image receptor 5 cm above the iliac crest. The exposure parameters were 82 kVp, 320 mA, 50 ms, x-ray field size 14×17 inch The distance between the center X-ray and the detector was fixed at 110 cm, and only the top two AEC chambers were used. As a result of this study, the medial and lateral side doses of the right breast were 535.73±30.68 μGy and 414.46±33.52 μGy for erect AP, and 145.80±18.52 μGy and 148.76±12.92 μGy in erect PA. The superficial breast dose was 754.00±68.36 μGy on the medial side and 674.06±45.58 μGy on the lateral side in the erect AP, 70.66±7.98 μGy on the medial side, and 86.46±15.35 μGy on the lateral side in the erect PA. There was a statistically significant difference in the difference between the mean values of the medial and lateral side doses in the deep and superficial areas of the breast according to the postural change (p <0.01). As a result of this study, If the abdominal radiography was examined in the PA position, the dose reduction effect was 72.78% on the medial side, 64.10% on the lateral side of the deep breast, 90.62% on the medial side, and 87.17% on the lateral side of the superficial breast compared to the AP position.

• Journal of Korean Society of Transportation
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• v.14 no.2
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• pp.137-155
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• 1996

본 논문은 다이아몬드 인터체인지에서의 유고감지모형 개발을 위해 퍼지이론을 응용한 연구를 문서화 한 것이다. 지금까지의 교차로와 일반도로(고속도로가 아닌)에서의 유고감지에 관한 연구는 초기에 불과하다. 기존의 알고리즘들은 필요한 데이터 보존의 어 려움과 유고감지의 특성과 관련된 기술적 어려움을 효과적으로 극복하지 못하고 있다. 본 연구의 목적은 다이아몬드 인터체인지에서의 유고감지를 위한 새로운 모형을 개발하는데 있다. 이 연구를 통하여 개발된 유고감지 모형은 차량차단 유고(lane-blocking incidents) 를 감지하는데, 감지의 범위는 차량차단 유고의 경향이 교통 장황에 특정한 패턴을 형성 하고 그에 따른 신호제어전략의 조정이 요구될 때에 국한된다. 이 모형은 전통적인 통계 치를 이용한 유고감지감 고유의 문제를 해결하며, 보다 정확하고 신뢰성 있는 유고감지를 위해 다양한 교통변수를 이용하여 전체적인 유고의 경향을 포착한다. 또한 이 모형은 실 시간 교통대응 다이아몬드 인터체인지 신호제어 시스템 (real-time traffic adaptive diamond interchange control system)의 구성요소로써 사용되며, 그리고 더 큰 교차로 시스템에의 상용을 위하여 확장이 용역하도록 설계되었다. 본 연구를 통해 개발된 프로 토타입(prototype) 유고감지 모형은 실제의 다이아몬드 인터체인지에 적용되어, 감지율, 오보율, 평감지시간의 세 달로써 성능이 평가되었다. 모형의 성능평가 결과는 무적이었으 며, 퍼지이론은 유고감지에 효과적인 접근방법임을 확인할 수 있었다.투자의 타당성을 실증적으로 보여 주고 있다.산정 절차 정립에 엇갈림 알고리즘을 활용하는 방안을 제시하였다.자함수를 추정한 뒤 이를 이용해 업종, 기업규모, 상품유형별로 적합한 모델(Fixed Effects Model)을 결정하고, 각각에 해당하는 통계모형을 구축하였다. 이 결과 (1) 업종 및 기업규모별로 그룹간에 유의한 특성이 발견되었으며, (2) R&D 및 광고투자는 기업의 시장성과를 설명하는 중요한 변수이나, (3) R&D 투자의 경우는 광고에 비해 불확실성이 존재하는 것으로 나타났고, (4) 수리모형에서 도출된 한계원리가 통계모형에서도 유효한 것으로 드러났다.등을 토대로 한 10대 산업을 육성하기 위하여 과학기술부는 기술수요조사를 바탕으로 49개 주요기술을 도출하여, 과학기술 일류 국가 실현, 국민소득 2만불 달성이라는 국가적 슬로건을 내걸고 “차세대 성장동력” 창출을 위한 범정부차원의 기획과 연구비의 집중투자를 추진하고 있다.달성하기 위해서는 종합류류 전산망의 시급한 구축과 함께 화물차의 적재율을 높이고 공차율을 낮출 수 있는 운송체계의 수립이 필요한 것으로 판단된다. 그라나 이러한 화물전용차선의 효과는 단기적인 치유책일 수밖에 없기 때문에 물류유통 시설의 확충을 위한 사회간접자본의 구축을 서둘러 시행하여야 할 것이다.으로 처리한 Machine oil, Phenthoate EC 및 Trichlorfon WP는 비교적 약효가 낮았다.>$^{\circ}$E/$\leq$30$^{\circ}$NW 단열군이 연구지역 내에서 지하수 유동성이 가장 높은 단열군으로 추정된다. 이러한 사실은 3개 시추공을 대상으로 실시한

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.989-995
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• 2010

The aim of this study was to investigate the effect of Taeeumjowuitanggagam-bang(TJV) on the mRNA expression of adipocytokines (TNF-${\alpha}$ and IL-6), and SREBPs. Mice were divided into 4 groups ; a normal group of db/+ mice, a control group of db/db mice, a group (db/db mice) treated with TJV 200 mg/kg, and a group (db/db mouse) treated with TJV 500 mg/kg. They were treated orally with TJV and measured their body weight every other day during 9 weeks. After that, we measured the mRNA expression of adipocytokines (TNF-${\alpha}$ and IL-6) and SREBPs (SREBE-1a and SREBP-1c) in liver, and blood concentration of total cholesterol, triglyceride, too. In addition, liver samples were fixed in 4% PFA for 2 hours and stored in $-70^{\circ}C$. Liver tissues were embedded in Optical cutting temperature(OCT) compound and 30 ${\mu}m$ sections were cut. Tissue sections were stained Oil-Red-O to visualize neutral lipids. Nuclei were stained with hematoxylin solution. In result, the TJV reduced the mRNA expressions of TNF-${\alpha}$ and IL-6 and SREBPs in liver and stained liver tissue less red than control group. However, there was no significant differences in total cholestreol and triglyceride blood concentration and body weight among groups. The TJV has inhibitory effect on the mRNA expression of adipocytokines and SREBPs. Therefore, it is assumed that the TJV is related to inhibiting lipogenesis in the liver

• The Journal of Internal Korean Medicine
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• v.36 no.4
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• pp.518-526
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• 2015

Objectives This study investigated the effect of purified safflower (Carthamus tinctorius Linne) and safflower seed (Carthamus tinctorius L. seed; CS) extract, using hot water and ethanol extract methods , on the osteogenic differentiation of MC3T3E1 cells.Methods The safflower and safflower seed were extracted with hot water and ethanol. The samples were concentrated by a rotary evaporator and then freeze-dried using a freeze-dryer. The MC3T3E1 cells were propagated and maintained in DMEM (Gibco) containing 10% FBS and a 1% antibiotic antimycotic solution. To induce osteogenic differentiation, the cells were treated for 14 days with DMEM with 10 mM β-glycerophosphate and 50 μM ascorbic acid. Extract doses were confirmed by the results of an MTT assay, and treatment of the extracts was performed in a differentiation medium every two days. The ALP staining and activity were tested after osteogenic differentiation for five days, and after 14 days, osteogenic differentiation was determined by alizarin red S staining. The mRNA expressions of osteogenic-related genes were quantified using quantitative real-time PCR.Results In the results of the MTT assay, all concentrations of safflower extracts had no toxicity in the MC3T3El cells. But in the groups of 100 ng/ml and 200 ng/ml concentrations of safflower seed extracts, the cell viability was significantly reduced by up to 40-50%. So we fixed the treatment concentration of the extract at 50 ng/ml. In the ALP and alizarin red S staining, all extract groups increased osteogenic differentiation compared with the control group. The water-safflower extract group showed the highest mRNA level of Alp, Runx2, and Dlx5 genes. The mRNA level of Ocn, an osteogenic gene related to late-stage differentiation, in the ethanol-safflower extract group increased the mineralization more significantly than in other groups.Conclusions These data suggest that the extract of safflower increases the osteoblastic differentiation activates of MC3T3E1 cells like the extract of safflower seed. The water-extract and ethanol-extract of safflower have effects on different stages of osteogenesis in MC3T3El. Not only safflower seed but also safflower will be useful therapeutic reagents for age-associated chronic diseases such as osteoporosis.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.478-478
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• 2012

Recently, there are many researches in order to increase the deposition rate (D/R) and improve film uniformity and quality in the deposition of microcrystalline silicon thin film. These two factors are the most important issues in the fabrication of the thin film solar cell, and for the purpose of that, several process conditions, including the large area electrode (more than 1.1 X 1.3 (m2)), higher pressure (1 ~ 10 (Torr)), and very high frequency regime (VHF, 40 ~ 100 (MHz)), have been needed. But, in the case of large-area capacitively coupled discharges (CCP) driven at frequencies higher than the usual RF (13.56 (MHz)) frequency, the standing wave and skin effects should be the critical problems for obtaining the good plasma uniformity, and the ion damage on the thin film layer due to the high voltage between the substrate and the bulk plasma might cause the defects which degrade the film quality. In this study, we will propose the new concept of the large-area multi-electrode (a new multi-electrode concept for the large-area plasma source), which consists of a series of electrodes and grounds arranged by turns. The experimental results with this new electrode showed the processing performances of high D/R (1 ~ 2 (nm/sec)), controllable crystallinity (~70% and controllable), and good uniformity (less than 10%) at the conditions of the relatively high frequency of 40 MHz in the large-area electrode of 280 X 540 mm2. And, we also observed the SEM images of the deposited thin film at the conditions of peeling, normal microcrystalline, and powder formation, and discussed the mechanisms of the crystal formation and voids generation in the film in order to try the enhancement of the film quality compared to the cases of normal VHF capacitive discharges. Also, we will discuss the relation between the processing parameters (including gap length between electrode and substrate, operating pressure) and the processing results (D/R and crystallinity) with the process condition map for ${\mu}c$-Si:H formation at a fixed input power and gas flow rate. Finally, we will discuss the potential of the multi-electrode of the 3.5G-class large-area plasma processing (650 X 550 (mm2) to the possibility of the expansion of the new electrode concept to 8G class large-area plasma processing and the additional issues in order to improve the process efficiency.