• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.803-810
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• 2022

The small modular liquid-metal fast reactor (SMFR) is an important component of advanced nuclear systems. SMFRs exhibit relatively low breeding capability and constraint space for control rod installation. Consequently, control rods are deeply inserted at beginning and are withdrawn gradually to compensate for large burnup reactivity loss in a long lifetime. This paper is committed to investigating the impact of control rod compensation operation on core neutronics characteristics. This paper presents a whole core fine depletion model of long lifetime SMFR using OpenMC and the influence of depletion chains is verified. Three control rod position schemes to simulate the compensation process are compared. The results show that the fine simulation of the control rod compensation process impacts significantly the fuel burnup distribution and absorber consumption. A control rod equivalent position scheme proposed in this work is an optimal option in the trade-off between computation time and accuracy. The control position is crucial for accurate power distribution and void feedback coefficients in SMFRs. The results in this paper also show that the pin level power distribution is important due to the heterogeneous distribution in SMFRs. The fuel burnup distribution at the end of core life impacts the worth of control rods.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.745-747
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• 2015

Astronomy is one of the interesting but difficult topics in science for elementary education. Therefore, it is interesting to create astronomy activities that children can understand clearly. The researchers developed activities by using astronomy and botany to improve writing skills. They have to glue the local flowers on the star pictures then write the name of those flowers, the name of the constellation and write an essay describing their work. The participants are into two groups. 71 $3^{rd}$ year undergraduate students who registered for teaching and are learning science as an elementary education subjec, and 10 $1^{st}$ grade student from the laboratory school of Ubon Ratchathani Rajabhat university. We can conclude that both groups were more interested in astronomy, they can tell the name of local flowers and not only used their imagination to create their work, but also to write great essays.

• Bulletin of the Korean Mathematical Society
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• v.52 no.1
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• pp.1-11
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• 2015

This paper is devoted to investigate the singular directions of meromorphic functions in some angular domains. We will confirm the existence of Hayman T directions in some angular domains. This is a continuous work of Yang [8] and Zheng [10].

• Animal Bioscience
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• v.35 no.10
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• pp.1616-1627
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• 2022

Objective: This work was conducted to investigate the effects of oxidative stress on meat quality, mitochondrial function, calcium metabolism and ferroptosis of broilers. Methods: In this study, a total of 144 one-day-old male Ross 308 chicks were divided into 3 groups (control group, saline group, and hydrogen peroxide [H₂O₂] group) with 6 replicates of 8 broilers each. The study lasted for 42 d. The broilers in the saline and H₂O₂ groups were intraperitoneally injected with 0.75% saline and 10.0% H₂O₂ on the 16th and 37th day of the experimental period respectively, the injection volumes were 1.0 mL/kg of broiler body weight. On the 42nd day of the experimental period, two chicks were randomly selected from each cage, a total of thirty-six chicks were stunned by electric shock and slaughtered to collect breast muscle samples. Results: The H₂O₂ exposure reduced pH value, increased drip loss and shear force of breast meat (p<0.05), impaired the ultrastructure and function of mitochondria. The H₂O₂ exposure damaged the antioxidant system in mitochondria, excessive reactive oxygen species carbonylation modified calcium channels on mitochondria, which impaired the activities of key enzymes on calcium channel, resulted in the increased calcium concentration in cytoplasm and mitochondria (p<0.05). In addition, the H₂O₂ exposure increased the iron content and lipid peroxidation (p<0.05), which induced ferroptosis. Conclusion: Oxidative stress could impair meat quality by causing mitochondrial dysfunction, resulting in calcium metabolism disorder and ferroptosis.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1267-1277
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• 2016

Currently, enzymatic synthesis of lactulose, a synthetic prebiotic disaccharide, is commonly performed with glycosyl hydrolases. In this work, a new type of lactulose-producing biocatalyst was developed by displaying β-galactosidase from Bacillus stearothermophilus IAM11001 (Bs-β-Gal) on the surface of Bacillus subtilis 168 spores. Localization of β-Gal on the spore surface as a fusion to CotX was verified by western blot analysis, immunofluorescence microscopy, and flow cytometry. The optimum pH and temperature for the resulting spore-displayed β-Gal was 6.0 and 75℃, respectively. Under optimal conditions, it showed maximum activity of 0.42 U/mg spores (dry weight). Moreover, the spore-displayed CotX-β-Gal was employed as a whole cell biocatalyst to produce lactulose, yielding 8.8 g/l from 200 g/l lactose and 100 g/l fructose. Reusability tests showed that the spore-displayed CotX-β-Gal retained around 30.3% of its initial activity after eight successive conversion cycles. These results suggest that the CotX-mediated spore-displayed β-Gal may provide a promising strategy for lactulose production.

• Animal Systematics, Evolution and Diversity
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• v.29 no.4
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• pp.267-271
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• 2013

In Japan, the wild house mouse Mus musculus consists of two lineages, one from Southeast Asia (Mus musculus castaneus; CAS) and one from northern Eurasia (Mus musculus musculus; MUS). However, the exact origins of the parental lineages are unclear. A recent work using mitochondrial sequences revealed that Japanese CAS and MUS are closely related to haplotypes from South China and the Korean Peninsula, respectively. Recent phylogeographic analyses using nuclear gene sequences have also confirmed a close relationship between Japan and Korea in the MUS component. However, the Japanese CAS components in the nuclear genome are likely to be unique and to differ from those of other CAS territories, including South China. Although the origins are still unresolved, these results allow us to conclude that two areas of the continent, South China and the Korean Peninsula, are the primary source areas of Japanese wild mice and suggest pre-historical introductions associated with certain historical agricultural developments in East Asia.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2481-2485
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• 2007

Spatially resolved, quantitative, non-destructive analysis using synchrotron x-ray reflectivity (XR) with subnano-scale resolution was successfully performed on the nanoporous organosilicate thin films for low dielectric applications. The structural information of porous thin films, which were prepared with polymethylsilsesquioxane and thermally labile 4-armed, star-shaped poly(ε-caprolactone) (PCL) composites, were characterized in terms of the laterally averaged electron density profile along with a film thickness as well as a total thickness. The thermal process used in this work caused to efficiently undergo sacrificial thermal degradation, generating closed nanopores in the film. The resultant nanoporous films became homogeneous, well-defined structure with a thin skin layer and low surface roughness. The average electron density of the calcined film reduced with increase of the initial porogen loading, and finally leaded to corresponding porosity ranged from 0 to 22.8% over the porogen loading range of 0-30 wt%. In addition to XR analysis, the surface and the inner structures of films are investigated and discussed with atomic force and scanning electron microscopy images.

• Computers and Concrete
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• v.22 no.5
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• pp.469-479
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• 2018

The Brazilian tensile strength of concrete samples is a key parameter in fracture mechanics since it may significantly change the quality of concrete materials and their mechanical behaviors. It is well known that porosity is one of the most often used physical indices to predict concrete mechanical properties. In the present work the influence of porosity shape on concrete tensile strength characteristics is studied, using a bonded particle model. Firstly numerical model was calibrated by Brazilian experimental results and uniaxial test out puts. Secondly, Brazilian models consisting various pore shapes were simulated and numerically tested at a constant speed of 0.016 mm/s. The results show that pore shape has important effects on the failure pattern. It is shown that the pore shape may play an important role in the cracks initiation and propagation during the loading process which in turn influence on the tensile strength of the concrete samples. It has also been shown that the pore size mainly affects the ratio of uniaxial compressive strength to that of the tensile one in the simulated material samples.

• BMB Reports
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• v.41 no.10
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• pp.699-704
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• 2008

Embryonic stem (ES) cell-derived cardiomyocytes (ESCMs) must be specifically purified in order to prevent teratoma formation, and this confusing issue has hampered their clinical application. We therefore investigated a technique to generate pure labeled ESCMs for possible use in cardiac repair. We generated transgenic ES cell lines expressing enhanced green fluorescent protein (EGFP) under the transcriptional control of the $\alpha$-cardiac myosin heavy chain ($\alpha$-MHC) promoter. Differentiated EGFP-positive ES cells displayed characteristics of CMs. Furthermore, neuregulin-1 (NRG-1) upregulated the expression of the cardiac-restricted transcription factors Nkx2.5 and GATA-4, as well as differentiated CM factors ($\alpha$-MHC, $\beta$-MHC). Immunohistochemistry demonstrated that NRG-1 increased expression of cardiac-specific troponin T in the beating foci of the embryoid bodies. This work revealed a potential method for specifically labeling and enriching ESCMs by combining genetically-engineered ES cell clones and exogenous growth factor treatment.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.2
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• pp.143-150
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• 2021

The recent spread of novel and highly variant pathogenic viruses, including the coronavirus (SARS-CoV-2), has increased the demand for diagnostic testing for rapid confirmation. This has resulted in investigating the functional capability of each space, and preparing facility guidelines to secure the safety of medical technologists. During viral evaluations, there is a requirement of negative pressure facilities along with thread separation, during pre-treatment of samples and before nucleic acid amplification. Space composition therefore needs to be planned by considering unidirectional air flow. This classification of safety management facilities is designated as biosafety level 2, and personal protective equipment is placed accordingly. In case of handling dangerous materials, they need to be carried out of the biosafety cabinet, and sterilizers are required for suitable disposal of infectious agents. A common feature of domestic laboratories is maintenance of the sample pre-treatment space at a negative pressure of -2.5 Pa or less, and arranging separate pre-treatment and reagent preparation spaces during the test process. We believe that the data generated in this study is meaningful, and offers an efficient direction and detailed flow for separation of the inspection process and space functions. Moreover, this study introduces construction of the laboratory by applying the safety management standards.