천연 식품재료를 대상으로 superoxide dismutase 활성 측정법을 이용 superoxide radical 소거능에 대하여 검색하였다. 총 47종의 시료중 냉이 buffer 추출물이 11.6 unit/㎎ solid의 비교적 높은 활성을 나타내었으므로 이후 실험이 대상시료로 선정하였다. 냉이의 최적 추출용매를 선정하기 위하여 각종 용매로 추출한 후 수소공여능 및 linoleic acid에 대한 과산화지질 형성 억제능을 조사한 결과 에탄올 추출물에서 가장 높은 활성을 보였다. 냉이 에탄올 추출물은 50℃에서의 대두유 자동산화에 대해 항산화 활성을 나타내었으며, 에탄올 추출물 0.2% 첨가시 대조구에 비해 유도기간이 약 2배 증가하는 효과를 나타내었다.
Probiotic strain is known to regulate the immune system by colonizing in the intestine and interact with intestinal cell receptors of lymphoid tissue. In this study, safety of Streptococcus thermophilus KCTC14471BP and silk fibroin coating effects was evaluated with respect to mucin binding abilities and immune system modulation. S. thermophilus KCTC14471BP was coated with silk fibroin by adding 1% water-soluble calcium and 0.1% silk fibroin. S. thermophilus KCTC14471BP showed the high activities of leucine arylamidase and β-galactosidase. Regarding the antibiotic resistance tests, S. thermophilus KCTC14471BP was susceptible to ampicillin, vancomycin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline, and chloramphenicol. S. thermophilus KCTC14471BP coated with silk fibroin showed the improved mucin binding ability from 16.1% to 71.3% and was confirmed to have no cytotoxicity against RAW 264.7 macrophage. S. thermophilus KCTC14471BP coated with silk fibroin showed dose-dependently significant increases in pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. These results suggested that S. thermophilus KCTC14471BP can be expected as a promising probiotic bacteria for applications to food industries such as fermentation or functional foods.
This paper was evaluated manufacturing properties for core material of self-healing capsules using cement powder, it was found that coagulants for coagulation of core materials were important factors in manufacturing core materials.
This paper was evaluated manufacturing properties for core material of self-healing capsules using cement powder, it was found that coagulants for coagulation of core materials were important factors in manufacturing core materials.
As a first step of mapping genes conferring resistance to the brown planthopper, Nilaparvata lugens Stål, in Gayabyeo using a population derived from a cross between Gayabyeo and Taebaegbyeo, we performed the whole genome resequencing of these two Tongil-type rice varieties. The amount of raw sequence data was about 18.5X109 bp and 17.9X109 bp in Gayabyeo and Taebaegbyeo, respectively. After quality trimming and read mapping onto Nipponbare reference genome sequence, 9.3X109 bp was mapped in Gayabyeo with mapping depth of 25.0X, and 9.5X109 bp was mapped in Taebaegbyeo with mapping depth of 25.5X. Between Gayabyeo and Nipponbare, 1,585,880 SNPs were detected, while 1,416,898 SNPs were detected between Taebaegbyeo and Nipponbare. Between Gayabyeo and Taebaegbyeo, 284,501 SNPs were detected. Among the SNPs between Gayabyeo and Taebaegbyeo, 21.2% were in genic region and 78.8% were in intergenic region. In CDS region, 15,924 SNPs were detected, among which synonymous SNPs covered 47.3% and non-synonymous SNPs covered 52.7%. We designed Cleaved Amplified Polymorphic Sequences (CAPS) markers with SNPs in the restriction enzyme recognition sites, and 20 CAPS markers were tested. Of the 20 markers, 19 markers showed polymorphism and one marker showed monomorphism between Gayabyeo and Taebaegbyeo. It is expected that sufficient DNA markers for mapping genes with a population derived from a cross between Gayabyeo and Taebaegbyeo can be developed based on the results of the study.
This study was examined the variation of unit water content and fine aggregate ratio in concrete for nuclear power structure using a large amoung of crushed sand.
With the development of nanotechnology, nanomaterials are used in various fields. Therefore, the interest regarding the safety of nanomaterial use is increasing and much effort is diverted toward establishment of exposure assessment and management methods. Occupational exposure limits (OELs) are effectively used to protect the health of workers in various industrial workplaces. This study aimed to propose an OEL for domestic multi-walled carbon nanotubes (MWCNTs) based on animal inhalation toxicity test. Basic procedure for development of OELs was examined. For OEL estimation, epidemiological study and quantitative risk assessment are generally performed based on toxicity data. In addition, inhalation toxicity data-based no observed adverse effect level (NOAEL) and benchmark dose (BMD) are estimated to obtain the OEL. Three different estimation processes (NEDO in Japan, NIOSH in USA, and Baytubes in Germany) of OELs for carbon nanotubes (CNTs) were intensively reviewed. From the rat inhalation toxicity test for MWCNTs manufactured in Korea, a NOAEL of 0.98 mg/㎥ was derived. Using the simple equation for estimation of OEL suggested by NEDO, the OEL of 142 μg/㎥ was estimated for the MWCNT manufacturing workplace. Here, we used test rat and Korean human data and adopted 36 as an uncertainty factor. The OEL for MWCNT estimated in this work is higher than those (2-80 μg/㎥) suggested by previous investigators. It may be greatly caused by different physicochemical properties of MWCNT and their dispersion method and test rat data. For setting of regulatory OELs in CNT workplaces, further epidemiological studies in addition to animal studies are needed. More advanced technical methods such as CNT dispersion in air and liquid should be also developed.
본 논문은 강섬유의 일부를 철근집합체로 대체하여 초고강도 섬유보강 철근 콘크리트 I 형보의 연성거동을 유도하는 것을 목적으 로 한다. 강섬유와 철근집합체의 조합을 가진 초고강도 콘크리트 I 형보 대한 휨거동 실험을 수행하였다. 강섬유의 혼입률은 0%, 0.7%, 1%, 1.5%, 2%이다. 철근집합체와 PS강연선 집합체가 압축구역에서 콘크리트를 구속하기 위해 사용되었다. 철근집합체와 강연선 집합체의 길이 도 실험요소 중 하나이다. 이러한 실험요소를 조합하여 9개의 초고강도 철근 콘크리트 I 형보를 제작하였다. 강섬유 뿐만 아니라 종방향의 철근 집합체도 초고강도 철근 콘크리트 I형 보의 연성거동을 유도하는데 효과를 가지고 있다. 강섬유 혼입률 0.7% 또는 1%와 철근집합체를 사용한 조합이 I형 보의 효과적인 연성 거동을 보여주고 있다. 하중과 처짐관계 및 균열양상 등이 좁은 간격을 가진 작은 직경의 종방향 철근 집합체의 유용성을 나타내고 있다.
This study was investigated the influence of increase in compressive strength according to water reducing ratio. As a result of the analysis, it is determined that compressive strength according to water reducing ratio was increased by increasing the efficiency of cement.
This study was evaluated compressive strength of age 28 days of binary blended concrete according to there type of superplasticizer and there type of w/c. In addition, we are proposed modification prediction model equation that can reflect efficiency of water reducing and influence of binders using Lyse equation to predict the compression strength through the conventional W/C.
Recently, in Seoul there is a growing interest in the L type gutter between the street and the sidewalk because the broken gutter spoils the appearance of the city. The gutter has been viewed as an unimportant attached facility of the road despite an important drainage facility. Also, the gutter lost function by various deterioration actions is becoming hideous objects of streets. Accordingly, many engineers recognized problems about the gutter and tried to seek for solution. In this study, we desired to confirm that the inside of the gutter concrete was not deteriorated even if the surface of the gutter concrete was deteriorated by the de-icing salts. We could obtain thirty core specimens deteriorated by de-icing salts in Seongbuk-gu which is old downtown, has many hills such as Arirang-Hill, Miari-Hill, etc. in Seoul and test compressive strength. It was confirmed that the compressive strength of the gutter concrete follows normal distribution and it is statistically significant 1% level that the population mean of the compressive strength of the gutter concrete is more than 18MPa.
농업에 있어서 기술혁신이 필요한 시기이다. 전 세계적으로 자유무역경쟁체제가 심화되고 있다. 양질의 농산물을 저렴하게 생산 공급하는 국가와 기업이 경쟁력을 더 가지게 된다. 또한 농업 생산에 도전적인 요소로 가뭄 등 심각한 기후변화 상황에 직면하고 있다. 미래 농업은 ‘고생산력’, ‘고품질’ 그리고 ‘고경쟁력’을 마련하여 줄 수 있는 있는 기술혁신을 필요로 한다. 그 기술혁신은 식량 작물을 정밀하게 이해하는 것에서 시작한다. 피노믹스는 작물의 표현이나 기능을 로봇+영상+정보 기술을 농업에 융합하여 정밀하게 측정하는 시스템이다. 식물 표현 및 기능 관찰에 있어서 기존의 아날로그식 육안 관찰 방식으로부터 디지털 통합 융합기술시스템으로 진화를 한 것이다. 피노믹스는 기존 아날로그 방식에서 얻는 단순 정보보다 수십 배에서 수백 배에 상당한 생산성 및 품질 관련 정보를 획득 가능하게 하여 준다. 이는 농업 전 분야에 있어서 새로운 성장 동력이면서 경쟁력 향상에 큰 도움이 된다. 유럽의 여러 국가는 이런 점에서 피노믹스 관련 기술개발과 세계시장 확보에 전력을 다하고 있다. 특히, 현재는 종자산업 분야와 농업 생산물의 품질 관리에 적극 적용하고 있다.
피노믹스는 또한 우리나라 스마트 자동 팜의 기초기반기술이다. 피노믹스는 수천가지 작물 표현 및 기능 특성을 담은 빅데이터 생산이 가능하게 하여 준다. 작물 생장 반응 빅데이터는 최고의 생산성 획득을 위한 스마트 팜 환경 조절에 활용 가능하다. 피노믹스에서 얻은 식물 생산 능력 정보에다 생산물의 유통정보를 더하면 소비자 맞춤형 농업생산 공급이 가능하도록 하여줄 수 있다.
농촌진흥청은 2017년까지 80억을 피노믹스 인프라 구축에 투자 예정이다. 현재 농업 관련 연구개발 규모를 고려하면 더욱 큰 규모의 확실한 투자가 필요하다고 본다. 튼튼한 미래 혁신농업 구현을 위해서는 신속한 피노믹스 인프라의 구축 및 활용이 필요한 때이다.
In this paper, was examined the basic properties of mortar using perlite, vermiculite, natural and artificial lightweight aggregate as a part of the basic study for development of lightweight repair mortar.
This study evaluated the lateral thermal deformation induced by environmental factors for a precast I-girder. Lateral temperature gradients across the cross-section of the girder were calculated using analytical equations based on daily solar radiation, temperature variation, and wind speed. Then the lateral thermal deformation showed an average of approximately 40% to 71% of the tolerance for the initial lateral deformation of the girder, defined in the PCI bridge design standard.