• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2095-2103
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• 2021

A small power ADS design using thorium oxide and diluent matrix reprocessed fuel is proposed for a high transmutation rate, small reactivity swing, and strong safety features. Two fuel matrices (CERCER and CERMET) and different recycled fuel compositions recovered from UO₂ spent fuels with 45 GWd/tU and 60 GWd/tU burnup were investigated to determine the suitable fuel for the ADS. It was found that the transmutation of each isotope depends on TRU initial loading amount. After examining the cores, the results show that CERCER fueled ADS has a negative coolant void reactivity (CVR) and a smaller radiotoxicity at discharge compared to that of CERMET core. It implies that CERCER fuel has enhanced safety features and more flavor in terms of radiotoxicity management. To increase fuel utilization and core operation efficiency, a simple assembly shuffling pattern for the CERCER fueled ADS is also proposed. Eigenvalue and burnup calculations were conducted using Serpent 2 with ENDF/B-VII.0 library in both kcode and external source modes, and it indicates that the results of transmutation analyses obtained by kcode only is reliable to discuss the transmutation potential of ADS. Burnup calculation with the fixed-source mode is essential to be used for more practical results of the transmutation by ADS.

• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.941-948
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• 2023

Metabolites from medicinal plants continue to hold significant value in the exploration and advancement of novel pharmaceuticals. In the search for plants containing compounds with anti-inflammatory effects, we observed that the ethanol (EtOH) extract obtained from the aerial components of Gouania leptostachya DC. var. tonkinensis Pit. exhibited substantial suppression of nitric oxide (NO) in vitro. In a phytochemical study on an EtOH extract of G. leptostachya, 11 compounds were purified, including one unreported compound namely gouanioside A (1). Their chemical structures were unambiguously determined through the use of various spectroscopic techniques, such as 1 and 2D NMR, IR, and HR-ESI-MS, and by producing derivatives via chemical reactions. The EtOH extract, fractions, and a new compound exerted inflammatory effects by altering NO synthesis in murine RAW264.7 macrophage cells stimulated with lipopolysaccharide. The underlying inflammatory mechanism of the new compound 1 was also explored through various in vitro experiments. The results of this study indicate the potential usefulness of new compound 1 from G. leptostachya as a treatment for inflammatory diseases.

• Journal of Microbiology and Biotechnology
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• v.34 no.8
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• pp.1680-1687
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• 2024

The diverse pharmacological properties of edible bird's nest (EBN) have been elucidated in recent years; however, investigations into its antibacterial effects are still limited. In the present study, we explored the antibacterial activity of a peptide-rich extract of EBN against Staphylococcus aureus, a notorious pathogen. The EBN extract (EEE) was prepared by soaking EBN in 80% ethanol for 2 days at 60℃. Biochemical analyses showed that peptides at the molecular weight range of 1.7-10 kDa were the major biochemical compounds in the EEE. The extract exhibited strong inhibition against S. aureus at a minimum inhibitory concentration (MIC) of 125 ㎍/ml and a minimum bactericidal concentration (MBC) of 250 ㎍/ml. This activity could be attributed to the impact of the extract on cell membrane integrity and potential, biofilm formation, and reactive oxidative species (ROS) production. Notably, the expression of biofilm- and ROS-associated genes, including intercellular adhesion A (icaA), icaB, icaC, icaD, and superoxide dismutase A (sodA), were deregulated in S. aureus upon the extract treatment. Our findings indicate a noteworthy pharmacological activity of EBN that could have potential application in the control of S. aureus.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.367-374
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• 2022

In recent years, research into medicinal herbs with antioxidative activities has increased. Chrysanthemum morifolium and Chrysanthemum indicum are aromatic herb plants and that have long been used in traditional Vietnamese medicine. This study aims to evaluate the chemical compositions and antioxidative activities of essential oils hydrodistilled from the flower heads of C. morifolium and C. indicum. The chemical compositions of the essential oils were compared using gas chromatography/mass spectrometry (GC/MS) analysis. The antioxidative activity was determined and evaluated spectroscopically by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, metal chelating activity, reducing power, and total antioxidant capacity assays. According to the GC/MS results, chrysanthenone was predominant in the essential oils of both C. morifolium (64.14%) and C. indicum (32.02%). This is the first report of the identification of chrysanthenone as a major constituent of the essential oil of C. morifolium. Both Chrysanthemum oils were also revealed to possess antioxidant potential, exhibiting high antioxidative activities. In particular, the DPPH radical scavenging activities of the C. morifolium and C. indicum oils at a concentration of 100 mg/mL were 76.9 and 83.2%, respectively. The metal chelating values of C. morifolium and C. indicum were 0.85 and 0.76, whereas the reducing power values of that at 100 mg/mL were 0.76 and 0.71, respectively. This study provides the chemical properties of the essential oils of both C. morifolium and C. indicum grown in Vietnam and their potential antioxidant capacity.

• Communications of the Korean Mathematical Society
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• v.39 no.2
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• pp.279-302
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• 2024

In this paper, we summarise and present results on involution lengths and commutator lengths of certain linear groups such as special linear groups, projective linear groups, upper triangle matrix groups and Vershik-Kerov groups. Some open problems motivated by these results are also proposed.

• Archives of Pharmacal Research
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• v.27 no.11
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• pp.1106-1108
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• 2004

A new benzofuran derivative, named gymnastone [5-hydroxy-6-acetyl-2-(2-propane-1,2,3-triol)-benzofuran (1)], was isolated from the aerial part of Gymnaster koraiensis, together with viscidone (2) by repeated column chromatography. The structures of both compounds were identified by physico-chemical and spectral analysis including COSY, HMQC, and HMBC experiments.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.215-218
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• 2020

본 논문에서는 4차 산업혁명을 앞에 두고 베트남 기업들이 성장을 위하여 5G 모바일 커머스 연구를 진행한다. 최근 베트남 전자 상거래 시장은 유선 온라인과 모바일을 기반으로 빠르게 성장하고 있지만, 선진국의 전자상거래 모델보다는 아직도 문제점을 많이 가지고 있다. 우선은 파악된 베트남 전자상거래 모델의 단점을 극복한 다음에 5G 통신을 시작한다면 5G 커머스에 어떻게 적용 가능한지, 어떤 방향의 적용이 유리한지에 대하여 연구를 진행한다.

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.657-659
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• 2005

A new biflavonol glycoside named as solanoflavone (1) was isolated from aerial part of Solanum melongena. The chemical structure was elucidated as isorhamnetin-3-O-$\beta$-D-glucopyranoside-(4'$\to$O$\to$4"')-galangin-3"-O-$\to$-D-glucopyranoside on the basis of physicochemical and spectroscopic methods, including 2D NMR spectral techniques.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.175-183
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• 2012

Objectives: Controversy regarding the relationship between exposure to Agent Orange and disease has progressed for more than four decades, both at home and abroad. Recently, the allegation by US veteran Steve House of the burial of Agent Orange at the US Army base Camp Carroll located in Waegwan-eup, Korea, has emerged. We reviewed published articles and reports related to Agent Orange. Methods: Articles and reports were collected online using the keywords 'agent orange' and 'health' and then reviewed. Results: A number of epidemiologic studies have reported disease outcomes due to exposure to Agent Orange, while others were unable to establish a link to the injuries of veterans of the Vietnam War. This can be explained by the fact that accurate exposure assessment should be carried out since exposure misclassification in epidemiologic studies can affect estimates of risk. In the case of the burial of Agent Orange at Camp Carroll, an exposure pathway could be through underground water supplies, which differs from the cases of Vietnam and Seveso in Italy. Conclusion: There still remains a dispute among academics regarding the relationship between exposure to Agent Orange and disease, although Agent Orange is a highly toxic chemical. This dispute indicates that accurate exposure pathway and exposure assessment is needed.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.1-8
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• 2020

The research examines how interactions of financial literacy and peer effect indicators impact financial market participation of Vietnamese investors. In this research, financial literacy indicator is constructed from two levels, namely, basic financial literacy and advanced financial literacy. An empirical study was carried out by investigating 387 individuals who are currently working in finance-related areas such as banking, insurance and real estate industries. The findings indicate that individuals with higher level of financial literacy, specifically those with advanced financial literacy level, tend to participate in financial market. However, individuals with basic financial literacy level tend to walk away from financial market because the nexus between basic financial literacy and financial market participation is found negative statistically significant. The findings also suggest that peer effect and perceived financial literacy have a positive significant relationship with financial market participation. These findings remain robust after endogenous problem is addressed by employing instrument variable (IV) method, especially Ivprobit regression. Hence, these findings recommend that policy-makers should design and develop financial literacy programs, specifically at sophisticated level, to adapt and overtake the trend in financial innovation development. This should be done, not only on individual, but also national scale to ensure greater financial market participation.