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.

We investigated the effect of a synthetic complement peptide C3a on the outcome of Brucella abortus 544 infection in a murine macrophage cell line RAW264.7 cell. First, we determined the highest non-cytotoxic concentration of the peptide in the cell line. We also found that the peptide significantly increased the growth of the bacteria at 8 and 24 h. Although the number of bacterial CFU was also elevated at 48 and 72 h, the increases were not significant as compared to controls. We further investigated the effect of C3a peptide on the growth of Brucella by pre-incubating the peptide at various temperatures and found that the effect was reversed at 24 h post-incubation suggesting that incubation of peptide at high temperatures including 65°C or 95°C could inactivate its action. This also could indicate the beneficial effect of high temperature during infection. Although several studies reported the inhibitory effect of different antimicrobial peptides including C3a, the present study preliminarily revealed that it had no positive contribution on the control of B. abortus 544 infection in vitro and indirectly to its receptor, CD88, which belongs to GPCR. Moreover, the encouraged further exploration of the effect of other similar peptides would be performed for the purpose of finding Brucella-host cell interaction for the control of disease progression.

Seasonal forecasting has numerous socioeconomic benefits because it can be used for disaster mitigation. Therefore, it is necessary to diagnose and improve the seasonal forecast model. Moreover, the model performance is partly related to the ocean model. This study evaluated the hindcast performance in the upper ocean of the Global Seasonal Forecasting System version 5-Global Couple Configuration 2 (GloSea5-GC2) using a multivariable integrated evaluation method. The normalized potential temperature, salinity, zonal and meridional currents, and sea surface height anomalies were evaluated. Model performance was affected by the target month and was found to be better in the Pacific than in the Atlantic. An increase in lead time led to a decrease in overall model performance, along with decreases in interannual variability, pattern similarity, and root mean square vector deviation. Improving the performance for ocean currents is a more critical than enhancing the performance for other evaluated variables. The tropical Pacific showed the best accuracy in the surface layer, but a spring predictability barrier was present. At the depth of 301 m, the north Pacific and tropical Atlantic exhibited the best and worst accuracies, respectively. These findings provide fundamental evidence for the ocean forecasting performance of GloSea5.

Two new free-living marine nematodes of the genus Belbolla Andrássy, 1973 belonging to family Enchelidiidae are newly described based on specimens obtained from a shallow subtidal sediment of the western and southern outermost islands of Korea. Belbolla koreensis sp. nov. differs from other species of the genus by the combination of the following characteristics: longer body length (3,080-3,462 μm long), eight oesophageal bulbs in the posterior region of pharynx, well-developed two winged precloacal supplements (anterior precloacal supplement slightly longer than posterior one: 47-59 μm vs. 43-46 μm long), strongly arcuated, very thick, L - shaped spicule (122- 127 μm long, 1.7-1.9 anal body diameter (a.b.d.) long) with three separated blunt distal tips, and well-developed relatively long cylindrical shaped gubernacular apophysis with blunt teeth covering two thirds of the dorsal margin (57-58 μm long, 0.8-0.9 a.b.d. long). Belbolla hoonsooi sp. nov. is characterized by the following combination of characteristics: longer body length (3,494 μm long), eight oesophageal bulbs in the posterior region of pharynx, well-developed two winged precloacal supplements (anterior precloacal supplement slightly longer than posterior one: 43 μm vs. 36 μm long), strongly arcuated, L - shaped spicule (119 μm long, 1.5 a.b.d. long) with three separated blunt distal tip, and well-developed relatively long inverted triangle shaped gubernacular apophysis with blunt teeth covering half of the dorsal margin (45 μm long, 0.6 a.b.d. long). Detailed morphological characteristics and illustrations of two new Belbolla nematodes from the Korean seawaters were provided by differential interference contrast microscopy. Comparative tables on biogeographical and morphological characteristics of Belbolla species are also provided herein.

겨울철 도심지 내 적설 피해를 줄이기 위해 사용되고 있는 제설제는 주로 염화칼슘을 사용하고 있으며 주변에 식재 된 식물에 피해를 줄 수 있다. 본 연구는 제설제로 이용되는 염화칼 슘의 농도별 처리에 따른 가침박달(Exochorda serratifolia)의 생장과 생리적 반응을 알아보기 위해 수행되었다. 실험처리는 염화칼슘 0(대조구), 1.0, 3.0, 5.0%를 일주일 간격으로 1회 200mL씩 화분에 관주하였다. 염화칼슘 1.0, 3.0% 처리구에서 가침박달의 초장, 초폭, 엽장, 엽수, 생체중, 건물중간 통계적인 유의성은 없었지만 염화칼슘 5.0% 이상의 처리구에서는 가침박달의 초장이 짧아지고, 엽수가 줄어들었으며 생체중, 건물중이 유의적으로 낮았다. 총 엽록소 함량은 대조구를 제외한 모든 염화칼슘 처리구에서 낮게 측정되었고, MDA는 모든 염화칼슘 처리구에서 대조구보다 높게 측정된 것으로 보아 모든 염화칼슘 처리구에서 가침박달이 염스트레스를 받은 것으로 판단된다. 하지만 염화칼슘의 농도가 높아질수록 Proline 과 SOD 활성이 증가하여 가침박달의 항산화 반응을 확인하였다. 염화칼슘 5.0%를 제외하고는 모든 염화칼슘 처리구와 대조구의 생육이 비슷한 것으로 보아 가침박달은 내염성이 강한 식물종이라고 판단된다.

본 연구의 목적은 한국 대학생들의 기초체력과 신체활동량이 폐기능과 상관관계가 있는지를 분석하고, 성별에 따른 차이를 검증하는데 있다. 건강한 참여자 312명(남성 150명[평균연령: 19.29±1.72세], 여성 160명[평균연령: 19.05±1.17세])은 신체조성, 기초체력, 신체활동량 설문지, 그리고 노력성폐활량 (FVC)과 1초간 강제호기량(FEV1)의 폐기능 검사를 수행하였다. 연구결과, 남학생의 폐기능은 우악력과 좌악력, 그리고 배근력과 관련이 있었고, 여학생의 폐기능은 모든 기초체력 하위 요인과 관련이 있었다. 또한 여성의 폐기능은 중강도 신체활동량과 관련이 있는 반면 남성의 폐기능은 신체활동량의 모든 하위 요인과 관련이 있었다. 본 연구의 주요 발견은 폐기능을 개선하기 위해서 남학생은 신체활동량을 증가시키고, 여학생은 기초체력을 향상시킬 필요가 있음을 제안한다. 대학생들의 폐기능을 유지하고 개선시키기 위해서는 폐기능 관련 인자에 대한 성별의 차이를 이해하고, 성별에 맞는 교육적 노력이 필요할 것이다.

Ocean biogeochemistry plays a crucial role in sustaining the marine ecosystem and global carbon cycle. To investigate the oceanic biogeochemical responses to iron parameters in the tropical Pacific, we conducted sensitivity experiments using the Nucleus for European Modelling of the Ocean–Tracers of Ocean Phytoplankton with Allometric Zooplankton (NEMO-TOPAZ) model. Compared to observations, the NEMO-TOPAZ model overestimated the concentrations of chlorophyll and dissolved iron (DFe). The sensitivity tests showed that with increasing (+50%) iron scavenging rates, chlorophyll concentrations in the tropical Pacific were reduced by approximately 16%. The bias in DFe also decreased by approximately 7%; however, the sea surface temperature was not affected. As such, these results can facilitate the development of the model tuning strategy to improve ocean biogeochemical performance using the NEMOTOPAZ model.