표면발현(surface-display system)은 세포 또는 바이러스 표면에 목적 단백질을 고정하여 발현시킴으로써 목적 단백질에 대하여 독립적인 공간 구조 및 생물학적 활성을 부여하는 단백질 공학 기술이다. 또한 이를 이용하여 높은 중화항체 유도 및 대량생산이 가능한 삼량체의 형태로 항원 단백질의 발현 또한 가능하다. BES(baculovirus expression system)에서의 표면발현 기술은 번역 후 수정과정 및 복잡한 구조의 다양한 단백질의 발현이 가능하기 에 다른 숙주 기반 시스템보다 효율적이라고 보고되고 있다. 그러나 목적 단백질 외의 다른 표면 단백질과 발현 공간에서의 경쟁으로 목적 단백질의 낮은 생산량이 큰 문제점으로 지적되고 있다. 따라서, 이러한 BES에서 표면 발현의 생산 효율을 증대시키기 위하여, 동일한 표면 공간에 대한 단백질 간의 발현 경쟁에 대해 실험적으로 확인 후, 그를 해결하기 위하여 표면발현에 최적인 목적 단백질 발현을 위한 프로모터 선발 실험을 수행하였다. 이를 통해 BES에서 표면발현에 의한 목적 단백질의 생산 효율을 증대시킬 수 있음을 확인하였다.

부추속은 수선화과에 속하며 약 1000여종에 이른다. 좀부 추는 자생 부추속에 속하며 식용이 가능하고 크기가 작아 분 화식물로 적합하다. 이에 따라 본 연구는 좀부추를 분화 소재 로서 개발하기 위하여 식물의 측지성장을 촉진하고 꽃의 품질 을 향상시키기 위해 수행되었다. 이를 위하여 좀부추의 구근 을 생장조절제(GA3, BA, 에테폰, TDZ)에 다른 시간(1, 5시 간)동안 침지처리했을 때 식물의 생장과 꽃에 어떤 영향을 주 는지 조사하였다. GA3 처리구는 엽수와 자구의 수가 증가해 증식을 촉진시키는 효과가 있었다. 게다가 GA3는 화수의 증 가와 조기개화를 유도했다. 그러나 엽폭과 화경의 폭은 감소 하였다. 에테폰은 좀부추의 초장과 초폭에서 영향을 주지 않 았으나 1h에서 자구의 수가 증가하였다. 에테폰은 화서 발생 을 억제하여 화경의 수가 감소하였다. BA는 식물의 생장과 개 화 특성에 유의적인 영향을 보이지 않았다. TDZ처리한 식물 은 왜화되고 생육상태가 불량하였으며, 식물을 고사시켰다.

When decommissioning a nuclear power plant, the structure must be made to a disposable size. In general, the cutting process is essential when dismantling a nuclear power plant. Mainly, thermal cutting method is used to cutting metal structures. The aerosols generated during thermal cutting have a size distribution of less than 1 μm. The contaminated structures are able to generate radioactive aerosols in the decommissioning. Radioactive aerosols of 1 μm or less are deposited in the respiratory tract by workers’ breathing, causing the possibility of internal exposure. Therefore, workers must be protected from the risk of exposure to radioactive aerosols. Prior knowledge of aerosols generated during metal cutting is important to ensure worker safety. In this study, the physical and chemical properties of the aerosol were evaluated by measuring the number and mass concentrations of aerosols generated when cutting SUS304 and SA508 using the laser cutting method. High-resolution aerosol measuring equipment (HR-ELPI+, DEKATI) was used to measure the concentration of aerosols. The HR-ELPI+ is an impactor-type aerosol measuring equipment that measures the aerosol number concentration distribution in the aerodynamic diameter range of 6 nm to 10 um in real-time. And analyze the mass concentration of the aerosol according to the diameter range through the impactor. ICP-MS was used for elemental mass concentration analysis in the aerosol. Analytical elements were Fe, Cr, Ni and Mn. For the evaluation of physical and chemical properties, the MMAD of each element and CMAD were calculated in the aerosol distribution. Under the same cutting conditions, it was confirmed that the number concentration of aerosols generated from both materials had a uni-modal distribution with a peak around 0.1 um. CMAD was calculated to be 0.072 um for both SUS304 and SA508. The trend of the CMAD calculation results is the same even when the cutting conditions are changed. In the case of MMAD, it was confirmed that SUS304 had an MMAD of around 0.1 μm in size for only Fe, Cr and Mn. And SA508, Fe, Cr, Ni and Mn were all confirmed to have MMAD around 0.1 μm in size. The results of this study show that a lot of aerosols in the range of less than 1 μm, especially around 0.1 μm in size, are generated when metal is cut using laser cutting. Therefore, in order to protect the internal exposure of workers to laser metal cutting when decommissioning NPPs, it is necessary to protect from nano-sized aerosols beyond micron size.

The fuel fabrication facility has been built and is being operated by KAERI since licensing research reactor fuel fabrication in 2004. After almost 20 years of operation, outdated equipment for fabrication or inspection has been replaced by automated, digitalized ones to assure a higher quality of nuclear fuels. However, the generation of a large amount of radioactive waste is another concern for the replacement in terms of its volume and various types of it that should be categorized before disposal. The regulatory body, NSSC (Nuclear Safety and Security Commission) released a notice related to the classification of radioactive wastes, and most accessory equipment can be classified into the clearance levels, called self-disposal waste. In this study, the practice of self-disposal of metal radioactive waste is carried out to reduce its volume and downgrade its radioactivity. For metal radioactive waste, which is expected to occupy the most amount, analysis status and legal limitations were performed as follows: First, the disposal plan was established after an investigation of the use history for equipment. Second, those were classified by types of materials, and their surface radio-contamination was measured for checking self-disposable or not. After collecting data, the plan for the self-disposal was written and submitted to the Korea Institute of Nuclear Safety (KINS) for approval.

In the design of a spent-fuel (SF) storage, the consideration of burnup credit brings the benefits in safety and economic views. According to it, various SF burnup measurement systems have been developed to estimate high fidelity burnup credit, such as FORK and SMOPY. Recently, there are a few attempts to localize the SF burnup measurement system in South Korea. For the localization of SF burnup measurement systems, it is very important to build the isotope inventory data base (DB) of various kinds of SFs. In this study, we performed DeCART2D/MASTER core follow calculations and McCARD single fuel assembly (FA) burnup analyses for Hanbit unit 3 and confirmed the characteristic of the isotope inventory over burnup. Firstly, the core follow calculations for Cycles 1~7 were performed using DeCART2D/MASTER code system. The core follow calculation is very realistic and practical because it considers the design conditions from its nuclear design report (NDR). Secondly, the Monte Carlo burnup analyses for single FAs were conducted by the McCARD Monte Carlo (MC) transport code. The McCARD code can utilize continuous energy cross section library and treat complex geometric information for particle transport simulation. Accordingly, the McCARD code can provide accurate solutions for burnup analyses without approximations, but it needs huge computing resources and time burden to perform whole-core follow calculations. Therefore, we will confirm the effectiveness of the single McCARD FA burnup analyses by comparing the DeCART2D/MASTER core follow results with the McCARD solution. From the results, the use of single FA burnup analyses for the establishment of the DBs will be justified. Various FAs, that have different 235U enrichments and loading pattern of fuel rods and burnable absorbers, were considered for the burnup analyses. In addition, the results of the sensitivity analyses for power density, initial enrichment, and cooling time will be presented.

Minuartia laricina (L.) Mattf. is a Korean native plant with high potential as a commercial flowering potted plant due to its compactness and long flowering duration. However, because this plant is a groundcover, it is susceptible to lodging and leggy growth. Therefore, this study investigated the effects of plant growth retardants (PGRs) on the inhibition of stem elongation and flowering characteristics of M. laricina. Commercial products, Trimmit, Cycocel, and B-Nine, were used for the exogenous PGR application of paclobutrazol (PBZ), chlormequat chloride (CCC), and daminozide (DMZ), respectively. Application concentrations were 50 and 100 mg·L-1 for PBZ; 100, 500, and 1,000 mg･L-1 for CCC; and 500, 1,000, and 2,000 mg·L-1 for DMZ. Paclobutrazol was the only PGR that inhibited stem elongation. The stem lengths of the plants treated with 50 or 100 mg·L-1 PBZ were 2.2 cm (13%) or 9.8 cm (57%) shorter, respectively, than those of the control. 50 mg·L-1 PBZ retarded stem growth effectively without negatively affecting flowering or other growth parameters, whereas 100 mg·L-1 PBZ caused excessive dwarfing and significantly reduced flowering by 59%. CCC and DMZ applications were ineffective for growth control. Flowering time was accelerated with most PGRs, except for 2,000 mg·L-1 DMZ, reducing the time to flowering by 2–8 days. These results indicate that the stem growth of M. laricina was successfully inhibited with PBZ but not with CCC or DMZ. Thus, we concluded that a single application of 50 mg·L-1 PBZ or similar treatment is effective in miniaturizing M. laricina without causing harm to its growth or aesthetic value, such as the flower number. Additionally, because CCC and DMZ are not persistent in the growing medium, testing multiple application times for these PGRs is crucial.

At high temperatures, molten salt has heat transfer properties like water. Molten salt has the characteristics of a strong natural circulation tendency, large heat capacity, and low thermal conductivity. Unlike sodium, molten salt does not react explosively exothermically with air. However, molten salt has a strong tendency to corrode materials, and its properties are easily changed by a sensitive reaction to oxygen and moisture. Therefore, it is necessary to study material corrosion properties and chemical control methods for nuclear fuel salts, which are eutectic mixtures. In this study, the optimal operation method of the thermal convection loop is established to perform the experiments on the molten salt. The process describes briefly as follows. The operation step consists of preparation, purification, transportation, and operation. In the preparation, the step checks the entire structure and equipment (TC, blower, vacuum pump, etc.). And melt the salt mixture at a high temperature (670°C) slowly in the purification step. Before injecting the molten salt, the surface temperature of the entire loop must retain temperature (about 500°C) constantly. Completely melted molten salt in the melting pot is flow along the pipe of the thermal convection loop in the transportation step. Lastly, the convection of molten salt goes to keep by the temperature difference. The thermal convection loop can be utilized for various experiments such as corrosion tests, component analyses, chemistry control, etc.

Molten salt used in the multipurpose molten salt experiment must be of high purity. Depending on the purpose of the experiment, only the base component of the molten salt be used, or a component simulating a nuclear fission product be added to the base component and used. In all cases, an increase in the concentration of impurities such as oxygen and moisture may lead to an erroneous interpretation when analyzing the experimental results. Therefore, molten salt should be purified before use. In this study, the purification of molten salt is described for multi-purpose molten salt experiments. The salt mixture is selected as MgCl2-NaCl and is quantified at a mixing ratio of 43mol%:57mol%. The salt mixture is treated in a glove box environment because of must minimize the reaction of adsorbing oxygen and moisture when the salt mixture is exposed to the atmosphere. MgCl2 is more likely to contain water than NaCl, the purification of the NaCl-MgCl2 mixture is established according to the purification process for removing water from MgCl2. A process for purifying the salt mixture briefly consists as follows: drying moisture, melting salts, purification, removing HCl, and stabilization. Through the process be able to obtain high-purity molten salt and more accurate experiment results.

부추속 식물은 수선화과의 다년생 초본으로 약 1000여종에 이른다. 한국에서는 24종의 자생종이 분포하며 유전자원으로서 큰 가치를 지닌 분류군이다. 그러나 자생부추속 식물에 대한 연구는 일부 종에 대하여 한정적으로 이루어지고 있으며, 갯부추, 두메부추, 울릉산마늘과 같이 최근 분류되거나 잘 알려지지 않은 종에 대한 연구는 매우 부족하였다. 따라서 본 연구는 자생부추속 4종(강부추, 한라부추, 갯부추, 산부추)에 대한 온도 및 명암처리에 대한 발아특성을 조사하였다. 발아 특성은 발아율, T50, 평균발아일수, 발아균일도, 발아속도로 평 가하였다. 강부추와 갯부추는 5℃에서 50%이상의 발아율을 보였으나 한라부추와 산부추는 전혀 발아하지 않았다. 갯부추 는 남부지방 해변가, 강부추는 강이나 하천주변에 서식하며 한라부추와 산부추는 주로 산지에 서식하는 것으로 알려져있다. 따라서 이러한 차이는 종별 생육지의 환경조건에 따른 차 이로 추정된다. 5℃에서 강부추의 발아율은 명조건(70.0%)보다 암조건(93.3%)에서 향상되었으며, T50과 평균발아일수도 단축되었다. 한라부추는 15℃에서 암조건이 명조건보다 발아율이 증가하고 15℃와 20℃에서는 T50과 평균발아일수가 단축 되었다. 그에 따라 발아속도도 증가하였으며 발아균일도도 상 승하였다. 갯부추는 5℃에서 발아율은 명조건(70.0%)보다 암 조건(83.3%)에서 상승했고, 15℃에서 T50과 평균발아일수가 단축되었으며 발아속도가 증가하였다. 산부추는 15℃와 20℃ 에서 T50과 평균발아일수가 단축되었으며 발아속도가 증가하 였다. 따라서 상대적으로 낮은 온도 처리구에서 명조건보다 암조건이 일부 발아특성을 향상시켰다. 실험에 사용된 4종의 종자는 대부분 15~25℃에서 90%가 넘는 발아율을 보였으나, 다른 발아특성은 온도와 광에 따른 차이를 보였다. 강부추와 산부추의 T50, 평균발아일수, 발아속도는 20℃와 25℃에서 가 장 향상되었고, 한라부추와 갯부추는 25℃에서 T50과 평균발 아일수가 가장 단축되었으며, 발아속도도 가장 빨랐다. 결론적으로 발아특성을 종합적으로 고려했을 때, 강부추는 광과 관계없이 20~25℃, 한라부추는 광과 관계없이 25℃, 갯부추는 암조건 25℃, 산부추는 명조건 25℃와 암조건 20~25℃를 발아 에 적합한 조건으로 제시하였다.

본 연구는 기존에 절화용으로 개발되지 않았던 벼룩이울타리를 절화로써의 가치와 가능성을 증명함으로써 새로운 관상식물로 개발하기 위해 수행되었다. 실험은 온도, 보존용액, 절화 수명연장제에 따른 절화 벼룩이울타리의 영향을 구명하고자 절화수명, 수분흡수량, 생체중을 조사하였다. 수확 후 절화는 4, 15, 20, 25°C의 온도 조건에 따른 영향력과 1, 3% sucrose 와 8-hydroxqui-noline sulfate(8-HQS) 10, 50, 100mg･L-1 혼 용보존용액, 절화수명연장제 Chrysal와 Floarlife을 처리하였다. 저장 온도에 따른 실험 결과, 절화 벼룩이울타리는 저온 (4°C)에서의 저장에서의 절화수명이 대조구(7.8일)보다 29일 연장되었다. 온도가 낮을수록 절화의 품질과 수명에 가장 효과적이었다. sucrose와 8-HQS의 효과 확인을 위해 가장 낮은 농도의 당과 살균제를 혼용한 1% sucrose+8-HQS 10mg･L-1를 제외한 나머지 3개의 보존용액 대조구(6.5±0.5일)에 비하여 절화수명이 약 2주 연장되었다. 또한, 절화수명연장제 Chrysal 과 Floarlife는 sucrose와 8-HQS의 혼용보존용액과 절화수명에 유의적인 차이는 없었다. 한편, 모든 실험 조건에서 수분흡수량과 생체중의 급격한 감소는 절화수명의 단축됨과 연관이 있다는 것을 확인하였다.

본 연구는 한국근로자를 대상으로 하여 성장욕구가 직무열의와 직무탈진에 영향을 미치는지 조사하였 다. 이와 더불어 부정적 정서조절과 내적 동기가 이들 변수 간의 관계에 영향을 미치는지에 대해서도 검증하였다. 본 연구를 위해 한국의 제조기업에 근무하는 244명의 근로자에게 자기보고식 설문조사를 실시 하였다. 연구결과, 직무열의와 직무탈진에 대한 성장욕구의 직접 효과는 없는 것으로 나타났다. 그러나 이들 변수들 간의 관계는 부정적 정서조절과 내적 동기의 매개역할에 의해 강화되는 것으로 나타났다. 즉 성장욕구와 직무열의의 관계에 대해 부정적 정서조절과 내적 동기는 매개효과를 가졌으며, 성장욕구와 직무탈진의 관계에 부정적 정서조절이 매개효과를 가졌다. 이 결과를 통해 본 연구는 성장욕구와 직무 열의, 직무탈진의 관계에 대한 부정적 정서조절 및 내적 동기와 같은 심리적 특성의 중요성을 확인하였다.

딸기는 다년생 초본성 식물로 그 과실은 영양 가치가 높고 인기있는 고부가가치 채소작물이다. 본 연구는 딸기 품종 ‘설향’과 ‘매향’의 런너유인각도(RTA)가 절간장과 런너 발생수에 미치는 영향을 조사하여 자묘의 생산성을 높이고 번식효율을 증가시키기 위한 기초 자료를 얻고자 수행되었다. 러너를 0°(상향), 45°, 90°(수평), 135°, 또는 180°(하향)의 각도로 한 달 간 유인하였다. 이 실험은 유리온실에서 주간/야간 온도 29/20°C, 평균 광도 450 μ mol m-2·s-1 PPFD의 자연광 환경에서 수행하였으며, 1일 광주기는 12시간이었다. ‘설향’과 ‘매향’에 있어서 RTA는 런너 수와 절간장에 영향을 주었으며, 자묘 수, 생체중과 건물중에 영향을 미쳤다. RTA 135° 또는 180°에서 두 품종 모두 자묘의 평균 생체중과 건물중이 가장 작았으며, ‘설향’ 품종에서는 런너 길이와 절간장이 짧아졌다. RTA가 두 품종 모두에서 런너의 직경에는 영향을 미치지 않았지만 런너의 형태에는 영향을 미쳤다. RTA중 135°와 비교해서 180°가 가장 많은 자묘를 생산하여 가장 번식효율이 좋았다.

This study aimed to examine the effect of a mild elevation in serum cholesterol level in a porcine coronary overstretch restenosis model using a balloon angioplasty catheter or drug-eluting coronary stent. Pigs were divided into two groups and were fed a commercial normal diet (CND, n = 4) or a high-fat diet (HFD, n = 4) for 5 weeks. Coronary overstretch injury by balloon angioplasty or stent implantation was induced in the left anterior descending and left circumflex artery after 1 week of feeding. Histopathological analysis was performed at 4 weeks after coronary injury. During the experiment, the total cholesterol level in the HFD group increased by approximately 44.9% (from 65.9 ± 3.21 mg/dL at baseline to 95.5 ± 9.94 mg/dL at 5 weeks). The lumen area in the CND group was reduced in comparison with that in the HFD group after balloon angioplasty. After stent implantation, the injury score showed no significant difference. There were significant differences in the neointimal area (2.7 ± 0.33 mm2 in the CND group vs. 3.3 ± 0.34 mm2 in the HFD group, p<0.05), lumen area (2.6 ± 0.54 mm2 in the CND group vs. 2.0 ± 0.33 mm2 in the HFD group, p<0.05), and percent area stenosis (52.0 ± 7.96% in the CND group vs. 62.4 ± 5.15% in the HFD group, p<0.05). Body weight change was not different between the two groups. Increased serum cholesterol level activated vascular smooth muscle cell proliferation in the porcine coronary overstretch model.

Cryopreservation of boar semen is continually researched in reproductive technologies and genetic resource banking in breed conservation. For evaluating the boar semen quality, sperm motility (MOT) is an important parameter because the movement of spermatozoa indicates active metabolism, membrane integrity and fertilizing capacity. Recently, polymorphisms reported to be significant association with sperm MOT. This study was conducted to evaluate the SNP in the coding region of ESR1 (g.672C>T inexon 1) as a positional controlling for motility and kinematic characteristics of post-thawed boar semen. To results,The g.672C>T was significantly associated with frozen semen motility and kinematic characteristics. g.158 T>C SNP was high significantly associated with MOT, VCL, VSL and VAP Also, the SNP was low significantly associated with ALH.Therefore, we suggest that theSNP in the coding region of ESR1 (g.672C>T in exon 1) may be used as a molecular marker for Duroc boar Post-thawed semen quality.