• The Journal of Korean Academy of Prosthodontics
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• v.52 no.2
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• pp.74-81
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• 2014

Purpose: While studies have examined microleakage in endodontically treated teeth restored with posts, microleakage among post and adhesive systems remains a concern. This study compared the sealing properties of 3 adhesively luted post systems. Materials and methods: Thirty-six endodontically treated permanent maxillary central incisors were divided into 3 groups: Zirconia-glass fiber, Quartz-glass fiber, Polyethylene fiber posts. Post space was prepared and each post was adhesively luted with 3 systems. The specimens were separately immersed in freshly prepared 2% methylene blue solution for 1 week. The cleaned specimens were then embedded in autopolymerizing acrylic resin. The root portion of tooth were horizontally sectioned into three pieces (apical, middle, and coronal portions). An occlusal view of each section was digitally photographed with a stereomicroscope. The methylene blue-infiltrated surface for each specimen was measured. Dye penetration was estimated as the ratio of the methylene blue-infiltrated surface to the total dentin surface. Results: No significant differences were found among post types. The variables of middle section and 3-stage adhesive produced significant differences in microleakage between the following post pairs: zirconia-glass fiber versus quartz-glass fiber, zirconia-glass fiber versus polyethylene fiber, and quartz-glass fiber versus polyethylene fiber (P<.05). There were significant differences between the apical and coronal sections of each post type, and between apical versus middle sections of quarze-glass fiber and polyethylene fiber posts (P<.05). Conclusion: No significant differences were found among post types. The 3-stage adhesive produced significant differences in microleakage between the following post pairs.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.1
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• pp.31-42
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• 1999

To investigate the effects of the composts made of sewage sludges on the physico-chemical properties of soil and growth of paddy rice, the variations of chemical properties in soil, the contents of inorganic matters and heavy metals in plant tissues, the contents of heavy metals in brown rice, the growth response of paddy rice and grain yield were investigated. The results were summarized as follows : The contents of organic matters, N, available $P_2O_5$ and exchangeable K in soil were increased by application of the composts. The contents of N and available $P_2O_5$ in soil were remarkably decreased at the harvesting time in comparing with the 20th day after application of the composts. The contents of heavy metals in soil were increased very slightly by application of the com-post. At the harvesting time, the contents of N and K were not varied in all plant tissues at the plot of the compost in comparing with the plot of the NPK. The content of $P_2O_5$ in plant was increased by application of the composts. The contents of heavy metals in plant tissues and brown rice were not changed among the treatments. When the composts were applied to the pot at the rates of 1,000, 2,000, 4,000 and 6,000kg/10a with NPK, the numbers of grain yield were increased with 3, 18, 44 and 54% in comparing with NPK plot, respectively. Dry weight, the numbers of tillers and spikelet of the rice plant were increased by application of the composts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1425-1432
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• 2010

This study was designed to investigate the effects of antioxidant and antibacterial activities of water, ethanol and methanol extracts from root, stem and flower stalk of Hagocho (Prunella vulgaris). The solvent extract yields from root were higher than those from stem and flower stalk, and water extract showed the highest extraction yield against ethanol and methanol extracts. The contents of total phenolic and flavonoid in ethanol extract were significantly higher in stem extract compared with those of root and flower stalk. In the case of water and methanol extracts, however, the contents were the highest in flower stalk. The electron donating ability and reducing power in all test groups were significantly increased in a dose-dependent manner, and antioxidant activities were the highest in methanol extract. In extracts from different parts of Hagocho, the antioxidant activity was the highest in flower stalk followed by stem and root. ABTS radical scavenging ability of water and methanol extracts was above 50% at $100\;{\mu}g/mL$ concentration. Antibacterial activities did not show significant differences depending on parts of Hagocho. However, antibacterial activity of ethanol extract was higher than those of other extracts.

• Journal of radiological science and technology
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• v.31 no.1
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• pp.25-31
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• 2008

Purpose : This study was conducted to understand for the diagnostic discordance of bone mineral density(BMD) in DEXA(Dual Energy X-ray Absorptiometry). And the diagnostic difference between lumbar spine and femur neck, forearm was evaluated using T-score. Materials and Methods : We studied 220 females measured BMD on lumbar spine, and femur neck, forearm including ward's triangle and ultra digital(UD). We were distinguished T-score into normal, osteopenia, osteoporosis(WHO classification) and evaluated discordance rate according to age and degree of bone loss. Correlation analysis and chi-square test between L-spine, L-4, femur neck, Ward, Forearm, UD were carried out. Results : In the lumbar spine, the number of normal were in 57(25.9%), osteopenia in 86(39.1%), osteoporosis in 77(35.0%). In the L-4 and ward's triangle, the number of osteoporosis were in 78(35.5%), in 126(57.3%). There was significant correlation between lumbar, femur neck and forearm BMD in all cases. The discordance of BMD between lumbar and femur were 57%, lumbar and forearm 43%, forearm and femur 51%. The discordance rates of normal, osteopenic, osteoporotic groups were 39%, 64%, 43%, respectively, showing the highest discordance rate in osteopenia patients. In normal group of lumbar spine, the discordance rate was 25%, 23%, 11%, 65%, 86% in 30', 40', 50', 60', 70', respectively. In osteopenia, osteoporosis group of lumbar spine, the discordance rate was 62%, 55%, 36%, 20%, 9% in 30', 40', 50', 60', 70', respectively. Conclusion : It was different of the results of BMD with lumbar, femur and forearm site. The discordance rate was decreased with age in osteopenia, osteoporosis lumbar spine. In osteopenia group, the discordance rate was the highest. So, it is necessary that the BMD of lumbar, femur neck and forearm should be checked.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.40-49
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• 2004

Phyllostachys pubescens planted in the Nambu Forest Experiment station in Jinju city of Gyongnam province was used, to investigate the physical and mechanical property of bamboo in this study. The ages of the P. pubescens were 1, 2 and 3 years, respectively. This experiment was carried out in August and January. The P. pubescens were divided into upper, middle and lower parts according to the growing points. The physical and mechanical properties of the P. pubescens were investigated before and after treatment of hot water and microwave irradiation. 1. The upper part of the P. pubescens indicated the highest static MOE according to the growing points. The range of the static MOE was from 70,000 to 110,000kgf/cm². 2. When P. pubescens were treated with hot water of 95℃, the ratio of softening was about 10~30%. 3. As microwave irradiation time was increased, the MOE values was decreased in both green and water-saturated bamboos. For the irradiation time of 20 and 30 seconds, the static MOE of P. pubescens was decreased up to about 50% comparing with non-treated.

• Food Science and Preservation
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• v.16 no.6
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• pp.959-964
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• 2009

The resveratrol contents in grapes showed a great variation according to the cultivars. In spite of it, a high resveratrol content in fruit was found generally in cultivars of Shigyoku, Pione, Muscat of Alexandria (black colored cultivars) and Muscatel Ruso, Gold Finger, Niunai (green colored cultivars). But in case included fruit stem and rachis, some cultivars, i.e. Shigyoku, Muscat of Alexandria and Baby Finger, showed relatively higher resveratrol content, and these cultivars could be advantageous for cultivation without chemical fungicide, because resveratrol was known as a phytoalexin. While resveratrol was not detected in fruit flesh, fruit stem and rachis contained considerably high content of resveratrol; that shows resveratrol may be synthesized in these parts.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.176-179
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• 2002

발의 구조는 사람에 따라 약간의 차이를 보이기는 하나 일반적으로 중앙을 기준으로 할 때 비대칭적(Asymmetric)인 구조를 보인다. 특히 동양인의 경우, 비대칭성에 의한 발의 좌우 편차는 서양인에 비해 큰 것으로 알려져 있다. 따라서 발 길이 뿐만 아니라 발 둘레, 발 높이, 볼 거스(Ball girth) 등을 고려할 경우 발의 형태는 더욱 다양해지며, 이를 고려한 족형의 개발은 신발 설계에 있어서 필수적으로 요구된다 하겠다. 이 논문은 전국 남녀 8000명의 좌, 우 발의 각 25개 부위 측정한 후 전문가들의 조언을 통해 가장 구두골 제작에 영향을 주리라 생각되는 발의 10개 중요 부위를 이용하여 현재 단순히 유아용, 아동용, 학생용, 성인용으로 구분되어진 구두치수를 Classification 기법을 사용하여 연령별로 적절하게 구분되어 구두를 개발할 수 있도록 하였다.

• Proceedings of the ESK Conference
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• 1996.10a
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• pp.85-90
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• 1996

현재 초,중,고등학교에서 사용하고 있는 책상과 의자는 학생들의 신장 등급에 따라 13호로 제작되 고 있음에도 불구하고, 신체부적합에 의한 편이도. 안전도에 문제를 안고 있다. 이러한 책상과 의자는 특히 장시간 앉아 있는 성장기 청소년의 신체 발달을 고려하지 않음으로 인해 그 개선책이 시급하다 하겠다. 다라서 본 연구에서는 설문조사를 통하여 초,중,고등하교 학생들의 감성적 선호도를 조사하 고, 1992년 표준과학연구소의 부위별 신체 측정 자료를 토대로, 자유 조절형의 인체공학적 책상과 의자 를 설계하였다. 이 인체공학적 설계는 한 호수의 제품으로 색상 4단계, 의자 3단계(조합 12 단계)조절 을 가능하게 했으며, 기존의 교구에서 발생하던 신체 부위 상해, 잘못된 자세로 인한 피로, 디자인적 고 려 부재의 문제들을 종합적으로 보완하였다. 이 인체공학적 책상과 의자는 표본 집단에서 그 편이도, 안전도, 개인적 선호도를 조사하여, 기존의 교구와 유의한 차이를 보였다. 중 저가로 제작 가능한 본 인 체공학적 책상과 의자는 실제초,중,고등학교에서사용 가능한 제품으로 사료되나, 본격적인 판매에 앞서 완제품에 대한 시장 평가가 요구된다.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.14 no.1
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• pp.153-161
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• 1984

Orthopantomograph는 치과진료에서 가장 일반적인 국외촬영방법으로 이용되고 있다. 저자는 1983년 서울대학교병원 치과진료부 치과방사선과에 래원한 환자중 Orthopantomogram을 촬영한 2,160명을 대상으로 골경화증의 성별, 연령별 발생빈도와 발생부위, 경화상의 크기, 모양등을 분류하고 특발성 골경화증과 condensing osteitis에 관하여 관찰하였든 바 다음과 같은 결과를 얻었다. 1. Idiopathic osteosclerosis의 발현율은 16.0%, condensing osteitis의 발현율은 9.8%였고 남녀간의 차이는 없었다. 2. 골경화증의 호발부위는 하악소구치, 대구치부위였고, 상악에서의 발생율은 적었다. 3. 골경화상의 크기는 idiopathic osteosclerosis는 10㎜이내였고, condensing osteitis는 10-20㎜의 폭경을 가지고 있었다. 4. 골경화상의 형태, 건강골과의 경계 및 발현되는 상태는 일정하지 않았다.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.85-90
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• 1999

This study was conducted to investigation of effect of removal times and parts of leaf sheath by planting deph(0.6cm) on growth and flowering in forcing of Lilium species. Plant height is reduced by leaf sheath removal at early growth stages when bulbs were planted 6 cm of depth in 'Gelria and 0 cm in both of Jolanda' and Dream Land', respectively, but stem diameter and flower size were little different. Days to flowering of 3 cultivar except 'Gelria' were shorten in 6cm plant depth.