There are many types of foam molding methods. The most commonly used methods are the pressure foaming method, in which foam resin is mixed with a foaming agent at high temperature and high pressure, and the normal pressure foaming method, which foams at high temperature without pressure. The polymer resins used for foaming have different viscosities. For foaming under normal pressure, they need to be designed and analyzed for optimal foaming conditions, to obtain resins with low melt-viscosity or a narrow optimal viscosity range. This study investigated how changes in viscosity, molding temperature, and cross-link foaming conditions affected the characteristics of the molded foam, prepared by blending rubber polymer with biodegradable resin. The morphologies of cross sections and the cell structures of the normal pressure foam were investigated by SEM analysis. Properties were also studied according to cross-link/foaming conditions and torque. Also, the correlation between foaming characteristics was studied by analyzing tensile strength and elongation, which are mechanical properties of foaming composites.
어촌뉴딜 300사업은 300개의 어촌과 어항을 대상으로 하는 복합개발사업으로 낙후된 시설 개선 및 지역특화 자원활용 등 전문 프로그램을 제공하는 사업이다. 본 연구에서는 어촌뉴딜 300사업의 선정평가 항목 별 가중치 결정을 위해 다기준 평가방법인 AHP로 전문 가 설문조사를 통한 분석을 수행하였다. 평가결과, 상위계층 평가항목은 개발여건 및 기본구상, 사업효과, 사업계획, 사업 시행 및 관리 순으로 중요도가 높게 나타났다. 사업효과 항목은 가이드라인에서 6점으로 낮은 배점이었지만, AHP 결과 15.57점의 배점이 도출되었다. 본 연구에서 도출된 항목별 가중치는 향후 어촌어항 개발사업 평가항목 배점 선정에 참조할 수 있을 것이다.
We investigate the effect of the modification of cellulose acetate propionate as an organic vehicle for silver paste on solar cell efficiency. For the modification of cellulose acetate propionate, poly(ethylene glycol) is introduced to the hydroxyl groups of a cellulose acetate propionate backbone via esterification reaction. The chemical structure and composition of poly(ethylene glycol) functionalized cellulose acetate propionate is characterized by Attenuated total reflectance Fourier transform infrared, 1H nuclear magnetic resonance, differential scanning calorimetry and thermogravimetric analysis. Due to the effect of structural change for poly(ethylene glycol) functionalized cellulose acetate propionate on the viscosity of silver paste, the solar cell efficiency increases from 18.524% to 18.652 %. In addition, when ethylene carbonate, which has a structure similar to poly(ethylene glycol), is introduced to cellulose acetate propionate via ring opening polymerization, we find that the efficiency of the solar cell increases from 18.524% to 18.622%.
In2O3 doped WO3 powders were prepared by a polymer solution route and their NO2 gas sensing properties were analyzed. The synthesized powders showed nano-sized particles with specific surface areas of 6.01~21.5 m2/g and the particle size and shape changed according to the content of In2O3. The gas sensors fabricated with the synthesized powders were tested at operating temperatures of 400~500 oC and 100~500 ppm concentrations of NO2 atmosphere. The particle size and In2O3 content affected on the initial sensor resistance in an air atmosphere. The highest sensitivity (8.57 at 500 oC), which was 1.77 higher than the sensor consisting of the pure WO3 sample, was measured in the 0.5 mol% In2O3 doping sample. In addition, the response time and recovery time were improved by the addition of In2O3.
원자력발전소 해체 시 발생하는 금속폐기물은 폐기물 중에서 많은 비중을 차지하고 있다. 본 연구에서는 국내 자체처분 규제 요건 및 국내 기관별 자체처분현황을 조사하였다. 실제 원자력발전소 해체 시 발생되는 금속폐기물의 자체처분을 위하여 RESRAD-RECYCLE 코드를 이용하였으며 26가지 시나리오에 대한 선량평가를 수행하였다. 평가결과는 원자력발전소 해 체 시 자체처분 및 재활용에 관한 사전자료로서 활용가치가 있을 것으로 사료된다. 추후 자체처분을 통한 처분비용 저감효 과 연구가 추가로 가능할 것으로 판단된다.
Most patients with chronic low back pain experience functional disability of trunk muscle, and limitations in physical activity. While there are many types of exercise programs available, in recent years sling exercise has been emerging as the exercise program for spinal stabilization. It has been supported by a great amount of research with positive findings on its effectiveness. This research studies the effects of bridging exercise, conducted on a sling, on pain level and trunk muscle activation in supine, sidelying, and prone positions during a 4 weeks period. 10 healthy people(normal group, n=10) and 28 patients with low back pain participated in this study. 28 patients were divided into two groups; one group participated in exercise with the sling(experimental group, n=14) and the other group exercised without the sling(control group, n=14). They were asked to use the Numerical Rating Scale(NRS) to answer to the level of their pain they felt (no pain: 0 point, severe pain: 10 points). During sling bridging exercises, the muscle activity level in each muscle measured in each position was standardized as three seconds of EMG signals during five seconds MVIC. In conclusion, the experimental group with four weeks of sling bridging exercise experienced a statistically significant reduction in the pain level(p<.05) and increase in the muscle activities of erector spinae when in supine position, internal oblique when in sidelying position, and rectus abdominis in prone position(p<.05). Regular sling bridging exercise reduces the low back pain and enhances other trunk muscle activation, thereby positively affect spinal stabilization.
매발톱꽃속(genus Aquilegia)에 속하는 국내 3분류 군과 외래종 9분류군을 대상으로 RAPD분석을 실시하 여 종의 특이성 및 종간 유연관계를 비교 분석하였다. RAPD분석은 annealing 온도가 높아 재현성이 뛰어난 20mer primer인 URP primer 12쌍을 사용하였다. 12 쌍의 URP primer 중 6개의 primer에서 polymorphism 을 보이는 DNA band가 검출되었다. 검출된 band는 약 4kbp~200bp의 비교적 넓은 범위에 분포되어 있었 다. 총 93개의 DNA band가 검출되었으며 이 중 81 개 DNA band(87.1%)가 polymorphic한 band 양상 을 보였다. Polymorphism을 보이는 DNA band는 각 primer에 대해 10~16개로, 평균 13.5개의 DNA band 가 검출되어 유사도 행렬 계산에 사용되었다. 유사도 행렬 작성 결과 약 52.7~90.3%의 범위 안에서 유사 도를 나타냈으며, 이를 기준으로 dendrogram을 작성한 결과, 약 63%의 유사도에서 2개의 group으로 나뉘는 것을 확인할 수 있었다.
Intussusception in adults is a rare disease entity; its clinical course and etiology are different from its pediatric counterpart. Furthermore, intussusception caused by intestinal tuberculosis is very rare. We report on a case of transient intussusception induced by intestinal tuberculosis. A 29-year-old female visited our hospital with a chief complaint of right lower quadrant abdominal pain. Abdominal computed tomography showed ileo-colic type intussusception. Intussusception was transient and showed spontaneous reduction. Colonoscopy was performed for evaluation of the cause and intestinal tuberculosis was probable on colonoscopic biopsy. Follow up colonoscopy showed improvement after administration of anti-tuberculosis medication and intestinal tuberculosis was then confirmed.
본 연구에서는 감태 효소 추출물과 그것의 폴리페놀 추출물의 화장품 원료로서의 효능을 알아보기 위하여 항산화, 항당화, 미백, 항염 효과와 관련된 실험을 실시하였다. 감태 효소 추출물과 폴리페놀 추출물은 강력한 라디컬 소거능을 가지고 있으며 BSA/Glucose 시스템에서 최종당화생성물의 형성을 저해하는 항당화 활성과 타이로시네이즈 저해를 통한 우수한 미백력을 가지고 있음을 확인하였다. 또한 두 추출물 모두 세포 내에서 PGE2와 NO 생성 저해를 통한 항염 효과를 나타내었다. 이러한 결과를 종합해 볼 때, 감태 효소 추출물과 그 폴리페놀추출물은 화장품 원료로서의 응용 가능성이 있을 것으로 사료된다.
화원4호'는 '일품벼'의 농업적 특성에 모로베레칸의 도열병 저항성 유전자가 이입된 근동질계통을 육성하기 위해 '일품벼'와 모로베레칸을 교배하고, 계속적인 여교배와 MAS를 병행 실시하여 유망한 계통 CR502-3-2 계통을 선발하였다. 생산력검정 시험 결과 조사된 형질 중 도열병저항성을 제외한 기타 형질에서는 '일품벼'와 유사한 근동질계통으로, 품종보 호원 출원 조건에 부합하여 '화원4호'로 명명하고 품종보호원을 출원하였다. 1. 출수기는 보통기재배에서
본 연구는 모로베레칸의 잎도열병 저항성유전자를 탐색하고, 이 저항성유전자와 연관된 분자표지를 탐색하기 위해 수행되었다. 도열병에 이병성인 일품벼와 도열병에 강한 모로베레칸을 교잡하여 육성된 140개 BC3F3 계통을 도열병 균계 반응을 통한 저항성 유전자 탐색에 이용하였다.
The objectives of this study were to identify QTLs for agronomic traits using introgression lines from a cross between a japonica weedy rice and a Tongil-type rice. A total of 75 introgression lines developed in the Tongil-type rice were characterized. A total of 368 introgressed segments including 285 homozygous and 83 heterozygous loci were detected on 12 chromosomes based on the genotypes of 136 SSR markers. Each of 75 introgression lines contained 0-9 homozygous and 0-8 heterozygous introgressed segments with an average of 5.8 segments per line. A total of 31 quantitative and 2 qualitative loci were identified for 14 agronomic traits and each QTL explained 4.1% to 76.6% of the phenotypic variance. Some QTLs were clustered in a few chromosomal regions. A first cluster was located near RM315 and RM472 on chromosome 1 with QTLs for 1,000 grain weight, culm length, grain width and thickness. Another cluster was detected with four QTLs for 1,000 grain weight, grain length, grain width and grain length/width ratio near the SSR marker RM249 on chromosome 5. Among the 31 QTLs, 9 (28.1%) Hapcheonaengmi3 alleles were beneficial in the Milyang23 background. ILs would be useful to confirm QTLs putatively detected in a primary mapping population for complex traits and serve as a starting point for map-based cloning of the QTLs. Additional backcrosses are being made to purify nearly isogenic lines (NILs) harboring a few favorable Hapcheonaengmi3 alleles in Milyang23 background.
In a previous study, we mapped 12 QTLs for 1,000 grain weight (TGW) in the 172 BC2F2 lines derived from a cross between Oryza sativa ssp. Japonica cv. Hwaseongbyeo and O. rufipogon. These QTLs explained 5.4 – 11.4% of the phenotypic variance for TGW. Marker-aided selection combined with backcrosses was employed to develop QTL-NILs for each QTL. BC2F2 lines with each target QTL were backcrossed to Hwaseongbyeo twice and then allowed to self to produce BC4F5 populations. SSR markers linked to TGW were employed to select QTL-NILs with the respective target QTL. Six QTL-NILs with the recurrent parent, Hwaseongbyeo were evaluated for nine traits for three years from 2007 and 2009. Differences were observed between each of the 6 QTL-NILs and Hwaseongbyeo in TGW. In addition to TGW, these QTL-NILs displayed differences in other agronomic traits possibly indicating a tight linkage of genes controlling these traits. The direction of the QTL for TGW in 6 QTL-NILs was consistent as in the BC2F2 lines from the same cross. Difference in TGW between each of the QTL-NILs and Hwaseongbyeo was associated with the difference in one or two grain shape traits; grain length, grain width, and grain thickness. SSR markers linked to the QTL for TGW will facilitate selection of the grain shape character in a breeding program to diversify grain shape and provide the foundation for map-based gene isolation. Also, the QTL-NILs developed in this report and the progenies from crosses between the QTL-NILs will be useful in clarifying epistatic interactions among QTLs for TGW.
We conducted a QTL analysis of grain quality traits using 117 BC3F4 and BC3F5 lines developed from a cross between Ilpumbyeo and Moroberekan. Genotypes of 117 BC3F5 lines were determined using 134 simple sequence repeat (SSR) markers. A linkage map constructed using 134 SSR markers was employed to characterize quantitative trait loci (QTL). The 117 BC3F4 and BC3F5 lines were evaluated for eleven grain quality traits in 2005 and 2006. A total of 18 QTLs were identified for eleven traits, and the phenotypic variance explained by each QTL ranged from 9.9% to 35.2%. Moroberekan alleles contributed positive effects in the Ilpumbyeo background at two QTL loci for 1,000 grain weight. Four QTLs, two for chalky rice and one each for 1,000 grain weight and head rice were consistently detected in two consecutive years indicating that these QTLs are stable. Clusters of QTLs were observed in three chromosome regions. One cluster harboring five QTLs including head rice and brown rice ratio near SSR markers RM190 and RM314 was detected on chromosome 6. Another cluster harboring grain weight and white belly was detected on chromosome 2. Increase in white belly at this locus might be due to the increase in grain weight due to the presence of the Moroberekan allele. The Moroberekan alleles at two QTL loci, gw3 and gw4 associated with increased grain weight might be useful in breeding programs to develop high-yielding cultivars.
"화원2호"는 종간교잡을 통해 화성벼의 근동질계통을 육성하고자 '97년 화성벼와 O. rufipogon을 교배하고, 계속적인 여교배와 MAS를 병행 실시하여 CR121-1-1 계통을 선발하였다. 생산력검정 시험 결과 조사된 형질 중 천립중, 출수기, 간장, 수당립수 등에서 화성벼와 차이를 보이는 화성벼 근동질계통으로, 품종보호원 출원 조건에 부합하여 "화원2호"로 명명하고 품종보호원을 출원하였다. 화원 2호는 중간모본 혹은 분자연구를 위한 재료로서도 유