• Natural Product Sciences
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• v.27 no.1
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• pp.36-44
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• 2021

The essential oils from the aerial parts (leaves and flowers) of Spiraea hypericifolia L. (Rosaceae), collected in Northern Kazakhstan, were obtained by distillation in two dispersion media (distilled water and 15% NaCl solution). The chemical composition of the essential oils was evaluated by GC-MS for the first time. The yield of the essential oil was 0.04% (in fresh growth conditions) and 0.02% (in dry growth conditions) respectively regardless of which dispersion media (H2O or 15% NaCl solution) was used at the isolation of essential oil. The main compounds were aliphatic hydrocarbons (alkanes) (40.6-53.2%), aldehydes (8.4-17.4%), diterpenoids (9.1-16.7%) and ketones (6.2-8.7%). Content of monoterpenoids was depended on dispersion media (2.2-3.6% where H2O was dispersion media and 8.4-8.5% where 15% NaCl solution was dispersion media). n-Heneicosane (17.4-34.1%) and n-tricosane (14.3-19.5%) were the main constituents of the essential oil of S. hypericifolia. There were many insects from different classes in S. hypericifolia at flowering. Important components such as α-methylene-γ-butyrolactone (0.8-2.8%), benzyl cyanide (0.7-1.1%), β-damascenone (1.2-2.9%), (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (1.8-2.7%), β-ionone (0.5-1.8%) and others were detected in small amounts.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.1
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• pp.58-65
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• 2021

In this study, as a method to increase the recycling of circulating fluidized bed combustion ash(CFBCA), CFBCA was utilized to produce autoclave aerated concrete product since CFBCA contains quicklime and calcium sulfate components that are required for the manufacture of autoclave aerated concrete. Successful achievement of such objective will bring cost reduction with high value addition, saving of natural resources, and the reduction of environmental load. Various mixing designs were designed to evaluate the properties of autoclave aerated concrete made of CFBCA. Based on series of experimental program, prototypes mix design for factory manufacturing was obtained. According to the experimental results, it was confirmed that gypsum can be replaced with CFBCA through the method of pre-treating the CFBCA as a slurry. It was possible to produce competitive autoclave aerated concrete products using CFBCA.

• Natural Product Sciences
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• v.27 no.1
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• pp.54-59
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• 2021

Bergenia ciliata (Family: Saxifragaceae) is a folklore remedy for the treatment of various ailments in Asian countries. Bergenin (1) has been isolated as an active constituent in many studies, however, the amount of bergenin has not been determined in all parts of the plant. A simple RP-HPLC method was developed to determine the amount of bergenin in methanol extracts of leaves, rhizomes and roots of the plant. Separation was achieved on an Agilent Eclipse XDB-C18 column maintained at 25 ℃ using isocratic solvent system (water: methanol: acetic acid; 62.5:37:0.5 v/v/v) adjusted at pH 2 0 at a flow rate of 1.0 mL/min. and detected at 275 nm. Correlation coefficient (0.9952) showed linearity of concentration (5-200 ㎍/mL) and response. The values of LOD (0.00947 ㎍/mL) and LOQ (0.02869 ㎍/mL) indicated that method was sensitive. The recovery of bergenin was 99.99-100% indicating accuracy of method. The methanol extract of rhizomes contained higher amount of bergenin (19.4%) than roots (9.2%) and leaves (6.9%). It is concluded that methanol extract of rhizomes is a better source of bergenin than other parts of the plant. The findings are useful for standardization of bergenin containing extracts and herbal preparations.

• Natural Product Sciences
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• v.26 no.4
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• pp.317-325
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• 2020

A new dimer stilbene [Monalittorin (1)] and ten known compounds [engeletin (2), aurantiamide acetate (3), lupeol (4), friedelin (5), quercetin (6), tiliroside (7), rutoside (8), astragalin (9), isoquercitrin (10) and quercimeritroside (11)] have been isolated from the leaves of Monanthotaxis littoralis (Annonaceae). The structures of these compounds were established by interpretation of their data, mainly, HR-TOFESIMS, 1-D NMR (1H and 13C) and 2-D NMR (1H-1H COSY, HSQC, HMBC and NOESY) and by comparison with the literature. The evaluation of their antimicrobial activities against three bacteria (Staphylococcus aureus ATCC 25923, Escherichia coli S2 (1) and Pseudomonas aeruginosa PA01) and three fungal strains (Candida albicans ATCC10231, Candida tropicalis PK233 and Cryptococcus neoformans H99) using broth micro dilution method, showed the largest antimicrobial activities of EtOAc fraction and compounds 1, 5, 6, 8 and 11 (MIC = 8 - 64 ㎍/mL). In addition, EtOAc fraction presented synergistic effect with Vancomycin and fluconazole against the tested microorganisms.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.596-603
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• 2020

In this paper, an experimental study was conducted to investigate the applications of bottom ash, which is an industrial by-product obtained from thermal power plants. Bottom ash was used as fine aggregate in this study, and an experiment was conducted to determine the characteristics of the bottom ash aggregate. In addition, 25, 50, 75, and 100% contents of crushed (natural) fine aggregate were replaced with bottom ash aggregate to produce concrete mixture including bottom ash. Thereafter, test results of the unit weight, ultrasonic velocity, compressive strength, and thermal conductivity of bottom ash concrete were obtained. Moreover, the effect of the curing ages of 28 and 91 days on the material characteristics of bottom ash concrete were identified. Test results showed that bottom ash used as fine aggregate had pozzolanic reaction. Finally, based on the extensive experimental results, relationships between thermal conductivity and unit weight, ultrasonic velocity, and compressive strength was suggested.

• The Plant Pathology Journal
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• v.37 no.2
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• pp.152-161
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• 2021

Sugar beet (Beta vulgaris L.) is known as a key product for agriculture in several countries across the world. Beet soil-borne virus (BSBV) triggers substantial economic damages to sugar beet by reducing the quantity of the yield and quality of the beet sugars. We conducted the present study to report the complete genome sequences of two BSBV isolates in Turkey for the first time. The genome organization was identical to those previously established BSBV isolates. The tripartite genome of BSBV-TR1 and -TR3 comprised a 5,835-nucleotide (nt) RNA1, a 3,454-nt RNA2, and a 3,005-nt RNA3 segment. According to sequence identity analyses, Turkish isolates were most closely related to the BSBV isolate reported from Iran (97.83-98.77% nt identity). The BSBV isolates worldwide (n = 9) were phylogenetically classified into five (RNA-coat protein read through gene [CPRT], TGB1, and TGB2 segments), four (RNA-rep), or three (TGB3) lineages. In genetic analysis, the TGB3 revealed more genetic variability (Pi = 0.034) compared with other regions. Population selection analysis revealed that most of the codons were generally under negative selection or neutral evolution in the BSBV isolates studied. However, positive selection was detected at codon 135 in the TGB1, which could be an adaptation in order to facilitate the movement and overcome the host plant resistance genes. We expect that the information on genome properties and genetic variability of BSBV, particularly in TGB3, TGB1, and CPRT genes, assist in developing effective control measures in order to prevent severe losses and make amendments in management strategies.

• International Journal of Oral Biology
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• v.45 no.4
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• pp.143-151
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• 2020

Streptococcus mutans and Streptococcus sobrinus play important roles in dental caries. Coptis chinensis is a natural product with antimicrobial activity against enterobacteria; however, its effects on oral streptococci are still unknown. Therefore, the effects of C. chinensis on the growth and biofilm formation of the representative cariogenic bacteria S. mutans and S. sobrinus were investigated for the possible use of C. chinensis as an anticaries agent. The C. chinensis extract was diluted with sterile distilled water, and 0.1-2.5% of the extract was used in the experiment. The effects of the C. chinensis extract on the growth and glucan formation of S. mutans and S. sobrinus were measured by viable cell counting and spectrophotometry at 650 nm absorbance, respectively. Crystal violet staining was also carried out to confirm the C. chinensis extract's inhibitory effect on biofilm formation. The C. chinensis extract significantly inhibited the growth of S. mutans and S. sobrinus at concentrations of ≥ 0.3% as compared with the control group. The viable cell count of colonies decreased by 1.7-fold and 1.2-fold at 2.5% and 1.25%, respectively, compared with the control group. The biofilm formation of S. mutans and S. sobrinus was inhibited by > 20-fold at C. chinensis extract concentrations of ≥ 1.25% as compared with the control group. In summary, the C. chinensis extract inhibited the growth and biofilm and glucan formation of S. mutans and S. sobrinus. Therefore, C. chinensis might be a potential candidate for controlling dental caries.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.4
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• pp.57-71
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• 2021

The purpose of the study is to derive an appropriate knitting method that can increase the appearance, wearability, and functionality through empirical research on the sleeve height knitting ratio of seamless knit wear. The study was conducted by producing seven types of experiment clothes according to knitting ratio to examine the characteristics according to the body armhole and sleeve height ratio. Specifically, after fit evaluatins, variance analysis (ANOVA) was performed to analyze the results of the evaluation, and the evaluated contents were converted into data. Among them, the items with significant results were intensively studied using the Duncan-test. The result showed that the height and the width of the sleeves vary depending on the knitting ratio. Test sweater A was the highest at 16cm, followed by test sweater B, test sweater C, test sweater D, test sweater E, test sweater F, and test sweater G at 4cm. The 1:1 ratio of test sweater A, was the highest, which is knitted in the same course as the body. The larger the difference in the ratio of body and sleeve, the lower the height of the sleeves. As a result of the appearance sensory evaluation, a significant difference was confirmed in the result values (p<0.001) from all items on the front, side, and rear. Specifically, the appearance of the test sweater B(2:4:2) on the front and test sweater C(2:4:3) on the side and rear side was the best. When the sleeves height is properly set, the ratio of the arm line to fit the design with a natural curve is analyzed as a very important factor. The results of this study are expected to be of practical use in product development and production that can increase the feeling when wearing and design satisfaction.

• East Asian Economic Review
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• v.26 no.1
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• pp.49-91
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• 2022

Recent years have witnessed renewed interest in Africa and public diplomacy has emerged as the vital tool being used to cultivate these relations. China has been leading in pursuing stronger economic partnership with Africa while middle powers such as Korea are also intensifying engagement with the continent. While previous studies have analyzed the implications of China's activities in Africa on advanced powers, none has examined them from the paradigm of middle powers. This study fills this gap by assessing China's activities in Africa, their economic engagement and implications for Korea's interest in Africa. The analysis is qualitative based on secondary data from various sources and literature. The study shows that China's public diplomacy strategy involves a high degree of innovation and has evolved to encompass new tools and audiences. China has institutionalized a cooperative model that permeates many aspects of governance institutions in Africa, enabling it to strengthen their relations. This could also be helping China to adjust faster leadership transitions in Africa. Whereas the US is still the most influential country in Africa, China is influential in economic policies and has outstripped the US in infrastructure diplomacy. This could be because African policy makers align more with China's economic model than the US' mainstream economics. Chinese aid to Africa has been diversified to social sectors that are more responsive to the needs of Africa. Trade and investment relations between China and Africa have deepened, but so does trade imbalance since 2010. China mainly imports natural resources and raw materials from Africa. But this product portfolio is not different from Korea and the US. China's energetic insertion in Africa using various strategies has significant implications for countries with ambitions in Africa. Korea can achieve its ambitions in Africa by focusing resources in areas it can leverage its core strengths-such as education and vocational training, environmental policy and development cooperation.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.463-470
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• 2021

Due to natural and human factors, dunhuang frescoes in China have gradually degenerated. China has conducted digital transformation of frescoes since 1990. However, it requires expensive research costs. Most of the visitors passively accept transformation contents and lack subjective participation. The paper focuses on produces a prototype of Dunhuang frescoes on the CoSpaces EDU. It was implemented as a metaverse through procedures such as transforming the cave into 3D, mapping images to the cave model and developing CoBlocks. The research puts forward a more specific methodology without expensive costs of development. The paper makes it easier to realize the immersive and interactive virtual Dunhuang frescoes world, to improve the tourism contents and educational effect. This research carries on the statistics to the product result which develops according to the user experience of 100 different ages, has obtained the good feedback. The research results need to be improved is to strengthen the processing of graphic details. Therefore, Optimization and improvement of the result will be carried out in the future research.