• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.13-18
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• 2020

Iron oxide nanoparticles were microencapsulated using fibroin, a protein polymer of silk fiber, for theragnostic applications. The content of iron oxide was determined to be 4.28% by thermogravimetric analysis and 5.11% by magnetometer. A suspension of murine fibroblast 3T3 cells grown in medium supplemented with iron oxide-microcapsules turned clear in response to the magnetic force and the cells aggregated to the magnet direction. Neodymium magnets placed on the top of the culture dish, and attracted cells to the center of the culture surface. The cells collected on the culture surface aggregated to form a rough spheroid of 2 mm in a diameter after 72 h. In the outer layer of the cell aggregate, cells were relatively large and gathered together to form a dense tissue, but the central part was observed to undergo cell death due to the mass transfer restriction. In the outer layer, iron oxide-microcapsules were lined up like chains in the direction of magnetic force. Using microCT, it was demonstrated that the iron oxides inside the cell aggregate were not evenly distributed but biased to the magnetic direction.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.218-225
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• 2016

Purpose: The purpose of this study was to evaluate the push-out bond strength of glass-fiber post cemented with different adhesive systems and surface treatments. Materials and methods: 160 tooth samples made from 48 human maxillary single-rooted teeth with similar root length were divided into 4 groups according to the adhesive system (no adhesive, Adper Single Bond 2, Clearfil SE Bond, Clearfil S3). Each group had 4 subgroups according to the post surface treatment methods (no treatment, sandblast, silane, sandblast and silane). Posts (Parapost Fiber White) were cemented with Rely X Unicem. The teeth were sectioned perpendicular to their long axis into 1-mm thick sections. The push-out tests was performed at a speed of 0.5 mm/min. The results were evaluated by 2-way ANOVA, 1-way ANOVA and multiple comparison procedures (Tukey test) (${\alpha}=0.05$). Results: Tukey test showed that the adhesive system significantly influenced the push-out strength. The Clearfil SE Bond group showed the highest value. Post surface treatments showed no significant effect. Conclusion: Bond strength of glass-fiber post cemented with self-adhesive resin cement using Clearfil SE Bond showed significantly higher values compared to other adhesive systems.

• Journal of Animal Science and Technology
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• v.51 no.3
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• pp.225-230
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• 2009

This experiment was carried out to investigate the effects of ruminally inserted artificial fiber (RIAF; polymerized fibrous implements) on growth performance, feed intake and carcass characteristics of Hanwoo steers. Thirty six steers averaging $368.3\pm20.3kg$ were randomly assigned into three groups: control group, the ruminal insertion of three pieces (T1), and five pieces (T2) of RIAF. Average daily gain, feed intakes and conversions among treatments were similar. Numbers of rumen villi were higher in RIAF treatment (T1 and T2) groups than control group, but they were not significant (p>0.05). The length of villi were significantly longer in T2 than control group (p<0.05). Fecal weight tended to decrease in T1 compared with the control group (p>0.05). There was no differences on carcass traits inc1uding longissmus muscle area, back fat thickness, marbling score, meat color, and fat color among treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.9-14
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• 2006

This experiment was carried out to breed the cold-tolerant variety of Italian ryegrass (Lolium multiflorum Lam.) at the Grassland and Forage Crops Division, National Livestock Research Institute, RDA at Suwon, Korea, from 1999 to 2005. The new variety 'Kogreen' is a diploid variety with a green leaf color and had semi-erect habit in late autumn and erect growth habit in early spring. The heading date of 'Kogreen' was on May 4, and for 'Florida 80' was May 2, both are considered as early-heading variety. 'Kogreen' was wider by 0.7mm in flag leaf width, longer by 2 cm in flag leaf length and shorter by 1cm in plant length than the control variety, Florida 80. Stem width of 'Kogreen' was similar to that of 'Florida 80' and 'Hwasan 101'. cold tolerance of 'Kogreen' was better than that of 'Florida 80'. Dry matter(DM) yield (12,884kg/ha) of 'Kogreen' was 3% less than that of 'Florida 80'. in vitro dry matter digestibility was 74.7% and total digestible nutrient was 65.1%, which are 3.6% and 1.5% higher than those of 'Florida 80', respectively. Acid detergent fiber and neutral detergent fiber of 'Kogreen' were 30.1% and 54.1% which are 1.9% and 1.3% lower than those of 'Florida 80', respectively.

• Conservation Science in Museum
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• v.13
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• pp.51-58
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• 2012

The Conservation Science Team of the National Museum of Korea has carried out the conservation on the mandolin-type bronze sword that was excavated from Weolnae-dong, Yeosu as had been requested by the Research Center of Dolmens in Northeast Asia. The mandolin-type bronze sword from Weolnae-dong, Yeosu is accounted to be the longest one among all the bronze swords of the same type that have ever been excavated until now and it was in a treated condition with the primary conservation treatment already achieved. Due to the corrosion in progress, it was in a very brittle condition being in two separate parts of the upper and lower parts. With the upper part exposed and the lower part with earth, they were urgently collected. The Conservation Science Team carried out the conservation treatment on them by connecting the lower part of the mandolin-type bronze sword to the upper part after making the lower part exposed, and then by using an estimated restoration method for lost portions. When carrying out the conservation treatment, the glass fibers of 10 wt% Paraloid B-72 (in Xylene) was used as a method for strengthening the brittle artifact, and a non-destructive analysis was carried out to identify the ingredients using the X-ray fluorescence spectrometer.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.119-124
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• 2008

Purpose: To present our experience with soft tissue reconstruction using anterolateral thigh free flap after resection of soft tissue sarcoma. Materials and Methods: Between January of 2003 and June of 2007, we treated 7 patients with soft tissue reconstruction using anterolateral thigh free flap after wide resection for soft tissue sarcoma. We retrospectively analyzed type and size of tumors, resection margin, size of defect after resection, time of operation, flap survival and complication. Results: The type of sarcoma was 3 synovial sarcoma, 2 malignant fibrous histiocytoma, 1 leimyosarcoma and 1 fibrosarcoma. The size of tumor varied from $3{\times}5\;cm$ to $7{\times}8\;cm$. The resection margins of tumors were negative in all cases. The size of soft tissue defect after resection varied from $6{\times}8\;cm$ to $15{\times}10\;cm$. The mean time of operation was 3.6 hours. All flaps were survived. Conclusion: Anterolateral thigh free flap appear to be ideal for reconstruction after wide resection of soft tissue sarcoma.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.157-167
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• 1996

The method of direct seeding on flooded paddy surface in rice is known to be the most labor saving cultural practice in rice. However, this method has a problem in practical use such as severe lodging occurring at the reproductive growth stage. The objectives of this study were observated degree of field lodging and variation of lodging-related characteristics with different seeding dates. The number of seedlings per m$^2$ were from 91 to 144 plants, and seedling ratios were from ranged from 61.7% to 91.8%. Days from seeding to flowering were shortened from 5 to 15 days by the later seeding dates. Heading dates of Ilpumbyeo, Seoanbyeo, Daecheongbyeo and Donjinbyeo on June 9 showed slightly elapsed on the critical stable heading time from, August 28 to 29. The culm length was effective in longer clum varieties than semidwarf varieties. The degree field lodging (degree of lodging: 0~9< 9 : complete lodging) in Obongbyeo and S101 with semidwarf varieties were 0.17, whereas 1.25 in Dongjinbyeo with long culm. The lodging resistant varieties and later seeding dates shortened the length of fibrous in the clum, and thickened fibrous in the clum, respectively. Obongbyeo and Sl0l showed stronger resistance to field lodging. The lodging resistant varieties, Obongbyeo and Sl0l, showed lower values of lodging index from 1.03 to 1.15 than those of lodging susceptible varieties, Daecheongbyeo and Palgongbyeo ranged from 1.42 to 1.70. Bending moment with leaf sheath were greater in lodging resistant varieties (Obongbyeo and Sl0l),1510.0~1930.4g.cm, than those in the lodging susceptible varieties (Daecheongbyeo and Palgongbyeo), 1127.2~1287.6g.cm.

• Journal of the Korean Society of Costume
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• v.45
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• pp.5-16
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• 1999

본 연구의 목적은 Navajo 직물의 역사적 발달을 고전시대를 중심으로 살펴보고 특히 외부영향에 따른 직물의 변화를 고찰하는데 있다. 구체적으로 1) 고전시대의 전통적인 직물은 어떻게 발달하였는가\ulcorner 2) 고전시대 직물의 전통적 요소와 외부영향요인은 어떤 점이 다른가\ulcorner 예 초점을 맞추었다. 연구방법은 아메리카 인디언의 이동,문화 Navajo 직조 및 직물에 대한 문헌을 바탕을 조사하였고 아리조나 주립박물과 아리조나 역사 박물관을 방문하였으며 박물관 안에 있는 전문가들의 조언을 듣고 연구의 자료를 보완하였다. 또 비교 미학적 차원에서 고전시대 navajo 직물의 전통적 요소와 외부영향 요인을 분석하였고 외부영향을 받은 직물의 예를 시각적자료로 제시하였다. 이연구는 인디언직물에 대한 이해, 고전시대. Navajo 직물의 문헌고찰을 통한 민족의복의 문화적측면에 기여할수 이고 현대적 감각을 지닌 Navajo 직물을 한국직물에 접목 응용하는데 도움을 줄수 있다 본 연구의 결과는 다음과 같다. 1. Navajo 직물을 고전, 전환, 양탄자 시대로 구분되었고. 이중에서 고전시대가 navajo 직물의 특성을 가장 잘 나타내었으며 발달된 직조기술을 보였다. Navajo인들의 직조기술은 1863년경 최고조에 달했다. Navajo 직물의 디자인 주제로 주로 인간을 둘러싸고 있는 환경에서 얻어졌고 이것들은 직선의 기하학적 형태로 구체화되었다. 또한 직물에 표현된 색도 자연과 밀접한 관련성을 갖는 있었다. 2. Navajo 직물의 주용한 용도는 여성용 드레스, 남성용 셔츠는 어깨에 걸치는 두르개였다. 여성용 드레스는 동일한 크기의 직물의 두장을 직조한 후에 꿰매었고 남성용 셔츠는 머리가 들어갈수 있는 구멍이 있는 장방형 판쵸 스타일이었다. 어깨에 걸치는 두르개는 여성의 경우 가운데가 검은색이고 가장자리가 푸른색인형태오 흰색과 붉은 색이 교대로 나타나는 형태의 2가지가 있었고 남성용은 고전시대의 대표라고 일컬어지는 족장 두르개였다. 3. Navajo 직물은 외부의 영향을 받아 많은 변화를 가져왔다. 즉 스페인 사람들로 인하여 면 섬유대신 양모섬유를 사용하게 되었고 전통적 모양과 다른직물이 출현하게 되었다. 또한 인디고 염류, 색소니 실, 바에타 직물의 도입으로 다양한 색상의 표현이 가능해졌고 이와 관련하여 다이아몬드 십자형 톱니형 무늬드이 나타나게 되었다. 4, 고전시대를 대표하는 직물로 족장 두르개, 쇼올, 안장덮개를 들수 있으며 이 직물들에서 뚜렷하게 외부영향 요인을볼수 있다. 즉 족장 두르개의 가장 정교한 단계에서 다이아몬드 무늬가 가장가리 가운데 모서리에 위치하여 9지점 배치를 이룬 것 쇼올의 경우 폭보다 길이가 긴 형태의 비전통적 모습을 나타낸 것 안장덮개에서 보여지는 여덟포인트 별 무늬도 외부의 영향을 받은예이다. 뛰어난 직조기술로 유명한 navajo인들은 변화에 잘 적응하는 특성을 갖고 있었다. 외부의 영향을 그들은 긍정적으로 받아들였고 자기 자신들의 필요에 맞도록 수정하여 정체감을 잃지 않으면서도 문화를 발전시켰다. 따라서 고전시대의 Navajo 직물은 고유적 요인과 외래적 요인의 조화를잘 나타내고 있으며 디자인의 탁월함이 세련됨 천연염료와 인조염료의 배\ulcorner에 의한 색상의 우월성 등으로 오늘까지 높이 평가되고있다.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.18-24
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• 2004

연구배경 : 플라스미노겐 활성 억제인자-1 (plasminogen activator inhibitor-1; PAI-1)은 허혈성 뇌경색의 발생의 원인이 되는 섬유소 용해작용의 저하를 매개하는 인자로서, PAI-1의 작용이 촉진되면 섬유소 용해기능이 저하되어 관상동맥 및 뇌혈관질환의 발생을 증가시키게 된다. PAI-1 유전자의 촉진자(promoter) 영역에는 -675 4G/5G (4G/5G)와A -844G (A/G)의 두 개의 유전자 다형성이 존재하며, 이는 PAI-1의 유전자 전사과정에 영향을 미쳐 혈청 PAI-1의 농도를 증가시키고 결과적으로 허혈성 뇌경색의 발생확률을 높이는 작용을 하게 된다. 연구방법 : 허혈성 뇌경색으로 진단 받은 167명의 환자와 173명의 건강인의 말초혈액에서 DNA를 분리한 후 PAI-1의 4G/5G와 A/G 유전자 다형성에 대한 연쇄중합반응 및 제한효소 절편길이 다형성 (polymerase chain reaction-restriction fragment length polymorphism; PCR-RFLP) 방법을 이용하여 허혈성 뇌경색 발생과 유전자 다형성과의 관계를 비교 분석하였다. 결과 : 허혈성 뇌경색 환자에서의 4G/4G의 유전자형의 빈도는 15.0%으로 정상 대조군의 33.5%에 비해 현저하게 낮게 나타났다 (P < 0.0001). 각각의 유전자형과 허혈성 뇌경색의 발생 위험도 (odd ratio ; OR)와의 관계를 분석했을 때 4G/4G 유전자형을 가질 경우 위험도는 0.35배로 현저하게 낮아졌으며, (P < 0.0001), 5G/5G 유전자형을 가질 경우 위험도는 4.49배 로 현저하게 높아졌다 (P < 0.0001). 그러나, A/G 유전자 다형성과 허혈성 뇌경색의 발생과는 유의한 연관성을 발견하지 못하였다. 결론 : 이상의 결과로 볼 때 PAI-1 유전자의 4G/4G 유전자형은 허혈성 뇌경색의 발생 비율을 감소시키는 작용을 하는 것으로 여겨진다.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.367-373
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• 1999

Increasing consumer demand for recycle of most paper products is challenging manufacturers to use lower value raw materials while maintaining high quality. This study was carried out to investigate the composition of old corrugated containers (OCC) and to manufacture printing and writing papers of over 85% (ISO) brightness by ECF and TCF bleaching from OCC. Fiber length of American old corrugated container (AOCC) was longer than that of Korean old corrugated container (KOCC) in fiber length. The former was composed of unbleached kraft pulp (UKP) of about 80 percentage, the latter about 20 percentage. OCC is feasible for manufacturing of pulps i.e., AOCC is for printing and writing papers and KOCC is for whiteboards, in the aspects of brightness and mechanical properties on the other hand, the cost of manufacturing upgraded papers by OCC is high because of bleaching chemicals. Neverthless, considering various aspects, especially environment, there are many advantages in recycling. In case of the treated AOCC pulp, over 85% (ISO) brightness can be achieved through TCF or ECF bleaching step, while the treated KOCC pulp did not allow high brightness through TCF bleaching. The tensile index of the bleached KOCC pulp was lower than that of the bleached AOCC pulp, but the burst and tear index of KOCC was higher than that of AOCC.