This study evaluated the immunogenicity of the Bacillus Calmette-Guérin (BCG) vaccine in a guinea pig model to refine preclinical assessment methods. 24 guinea pigs were divided into four groups for immunohistochemical, histopathological, and molecular analyses, including qRT-PCR and ELISA. The ELISA results revealed significant elevations in interleukin 2 (IL-2), interferon-gamma (IFN- ), and tuberculosis-specific antibodies in vaccinated guinea pigs, particularly γ notable after 6 weeks. Although lung cytokine levels remained unchanged, spleen gene expression showed significant differences in interleukin-17, interleukin-12, interleukin-1β, and C-X-C motif chemokine ligand 10 after 6 weeks. Immunohistochemistry revealed peak IL-2 expression at 8 weeks and significant IFN-γ and TNF-α expression at 6 weeks. This study confirmed the effectiveness of BCG vaccine in guinea pigs, providing crucial insights for future tuberculosis vaccine development and standardizing immune response indicators.
To identify some significant phenotypic characteristics of maize(zea mays) seeds, we have obtained Red, Green, Blue(RGB) digital image data from 82 recombinant inbred lines. Based on the collected image data, their morphological and color data were analyzed, and seven significant parameters were selected, including area, perimeter, length, width, circularity, roundness, and surface texture. The extracted RGB data were converted into color hex codes to visualize the representative colors of the seeds. These visualized colors were categorized into six groups: gray, yellowish white, yellow, grayish orange, purple, and brown. The results of maize seed phenotypic analysis using the RGB digital images in this study will serve as a useful tool for constructing a database of seed phenotyping database and establishing a standardized classification system.
The development of separation method of radioactive tritium is imperative for treating tritiumcontaminated water originating from nuclear facilities. Polymer electrolyte membrane electrolysis technology represents a promising alternative to conventional alkaline electrolysis for tritium enrichment. Nevertheless, there has been limited research conducted thus far on the composition of membrane electrode assemblies (MEAs) specifically optimized for tritium separation, as well as the methods used for their fabrication. In this study, we conducted an investigation aimed at optimizing MEAs specifically tailored for tritium separation. Our approach involved the systematic variation of MEA components, including the anode, cathode, porous transport layer, and electrode formation method. The water electrolysis efficiency and the H/D separation factor in deuterated water (1%) were evaluated with respect to both the preparation method and the composition of the MEA. To assess the long-term stability of the MEAs, changes in cell voltage, resistance, and the active electrode area were analyzed using impedance analysis and cyclic voltammetry. Furthermore, we examined H/D separation factor both before and after degradation. The results showed that MEAs with different anode/cathode configurations and electrode formation methods improved the electrolysis efficiency compared to commercial MEAs. In addition, the degree of change in the resistance value was also different depending on the electrode formation method, indicating that the electrode formation method has a significant impact on the stability of the electrolysis system. Therefore, the study showed that the efficiency and long-term stability of the water electrolzer can be improved by optimizing the MEA fabrication method.
For decontamination and quantification of trace amount of tritium in water, an efficient separation technology capable of enriching tritium in water is required. Electrolysis is a key technology for tritium enichment as it has a high H/T and D/T separation factors. To separate tritium, it is important to develop a proton exchange membrane (PEM) electrolyzer having high hydrogen isotope separation factor as well as high electrolyzer cell efficiency. However, there has not been sufficient research on the separation factor and cell efficiency according to the composition and manufacturing method of the membrane electrode assembly (MEA) Therefore, it is necessary to study the optimal composition and manufacturing method of the MEA in PEM electrolyzer. In this study, the H/D separation factor and water electrolysis cell efficiency of PEM electrolyzer were analyzed by changing the anode and cathode materials and electrode deposition method of the MEA. After the water electrolysis experiment using deionized water, the D/H ratio in water and hydrogen gas was measured using a cavity ring down spectrometer and a mass spectrometer, respectively, and the separation factor was calculated. To calculate the cell efficiency of water electrolysis, a polarization curves were obtained by measuring the voltage changes while increasing the current density. As a result of the study, the water electrolyzer cell efficiency of the MEA fabricated with different anode/cathode configurations and electrode formation methods was higher than that of commercial MEA. On the other hand, the difference in H/D separation factor was not significant depending on the MEA fabrication methods. Therefore, using a cell with high cell efficiency when the separation factor is the same will help construct a more efficient water electrolysis system by lowering the voltage required for water electrolysis.
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.