• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1228-1232
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• 2005

Four compounds, including two novel macrolides, were isolated from an endophyte Streptomyces sp. Is9131 of Maytenus hookeri. Spectral data indicated that these compounds were dimeric dinactin (1), dimeric nonactin (2), cyclo-homononactic acid (3), and cyclo-nonactic acid (4). Bioassay results showed that dimeric dinactin had strong antineoplastic activity and antibacterial activity.

• Journal of the Optical Society of Korea
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• v.20 no.6
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• pp.762-769
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• 2016

The dynamic modulation transfer function (MTF) for image degradation caused by sinusoidal vibration is formulated based on a Bessel function of the first kind. The presented method makes it possible to obtain an analytical MTF expression derived for arbitrary frequency sinusoidal vibration. The error obtained by the use of finite order sum approximations instead of infinite sums is investigated in detail. Dynamic MTF exhibits a stronger random behavior for low frequency vibration than high frequency vibration. The calculated MTFs agree well with the measured MTFs with the slant edge method in imaging experiments. With the proposed formula, allowable amplitudes of any frequency vibration are easily calculated. This is practical for the analysis and design of the line-of-sight stabilization system in the remote sensing camera.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.695-697
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• 2015

The wind field and precipitable water vapor over the Tibetan Plateau are analyzed using the numerical model WRF. The spatial and vertical distributions of the relevant meteorological factors are summarized, providing evidence for selecting and further evaluating an astronomical site. This study serves as a further demonstration towards astro-climate regionalization, and provides us with an essential database for an astronomical site survey over the Tibetan Plateau.

• (The)Study of the Eastern Classic
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• no.69
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• pp.401-418
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• 2017

This study aims to consider the effects that the type of Chinese characters of "Kangxizidian(康熙字典)" manufactured under order of Emperor Kangxi(康熙) had on the type of Chinese characters on Korea from the latter part of Joseon(朝鮮) Dynasty to the present time, and to look for the meanings it has in the studies on history of Chinese characters science and character type science in Korea. "Kangxizidian" was introduced to Joseon on the 5th year of King Yeongjo(英祖)' reign(1729), the type of Chinese characters of had great influence on that of Chinese characters in Korea at that time. This can be seen from the fact that the types of Chinese characters written in "Hongmoojeongwoon(洪武正韻)", "Yeboowoonlaek(禮部韻略)", "Saengsaengjabo(生生字譜)", "Kyujangjeonwoon(奎章全韻)", "Jeonwoonokpien(全韻玉篇)", etc. which were published after King Yeongjo mostly included the character types of "Kangxizidian". Also, as seen from the fact that Ministry of Education specified that the character types of "Kangxizidian" shall be based for the standard of writing for 'basic Chinese characters for Chinese writing education' which were revised and proposed in 2000, the influence are said to be great until now. However, the concrete consideration of the effects that "Kangxizidian" has had on the type of Chinese characters in Korea and studies on its significance has been partially made, and it can be said that the studies thereof has not been made in earnest. This study was intended to make concrete studies on the effects of "Kangxizidian" on the types of Chinese characters in Korea and the insignificance, supplementing materials not dealt with in existing studies. The subjects of study by period which were dealt with in this study are as follows. In this paper, we reinforce data not covered in previous studies. And studies of "Kangxizidian" and the relationship between the type of Chinese characters in Korea characters and the influences of the past. Lastly, I showed the significance of the shape of the "Kangxizidian" to the modern Korean character shape of Korea.

• The Korean Journal of Food And Nutrition
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• v.33 no.5
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• pp.532-543
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• 2020

This experiment was conducted to assess the high antioxidant activity varieties of Chinese cabbage (Brassica rapa L. ssp. pekinensis) from the 55 accessions. The antioxidant activity of Chinese cabbage were determined by the TPC, TFC, DPPH, ABTS, and chlorophyll, carotenoid contents. The TPC and TFC showed a range of 1.21~4.61 mg GAE/g DW, 0.18~3.09 mg CE/g DW. The DPPH and ABTS assay were in the range of 0.65~4.36 and 1.42~6.91 mg ascorbic acid equivalent (ASCE)/g DW, respectively. The UPLC analysis was performed quantitatively to identify chlorophyll and carotenoid in the Chinese cabbage extract. The levels of the total chlorophyll and total carotenoid were 86.60~1,235.91, and 75.86~490.11 ㎍/g, respectively. The comprehensive differences in the total and individual chlorophyll contents have also been observed among different varieties. These results will be valuable as basic data for the standardization of Chinese cabbage.

• Korean Journal of Materials Research
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• v.23 no.12
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• pp.745-756
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• 2013

Recent rapid development of the Chinese economy based on science and technology is challenging Korean industries and economy. Since the driving force for this rapid development of China is known to be scientific technologies, the purpose of this research is to confirm the current status of Chinese scientific research in the field of "Materials Science and Engineering" and propose a strategy for competition with China. Even though there are numerous journals of "Materials Science and Engineering", the 10 most popular journals with high impact factors were selected to cover general materials, nano materials, bio materials, and electronic materials. It was found that the number of scientific papers written by Chinese scientists for the materials field in the 10 journals was slowly increasing from the year 2000 until 2005, but has been rapidly increasing since 2005. This research found that Chinese research activities in the traditional metallic materials and nano materials have tremendously increased to occupy around 30 % or more papers published in several major journals related with materials science and engineering. On the other hand, bio materials and electronic materials research has not been pursued so actively; however, very recently the number of publications in these fields is also beginning to increase. To compete with this tremendously growing Chinese scientific development, Korea should have a policy of "selection and concentration" in materials-related fields, including basic science in nano, bio, and electronic materials.

• The Plant Pathology Journal
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• v.35 no.2
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• pp.178-187
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• 2019

Plants are exposed to biotic stresses caused by pathogen attack and complex abiotic stresses including heat and drought by dynamic climate changes. To alleviate these stresses, we investigated two bacterial stains, H26-2 and H30-3 in two cultivars ('Ryeokkwang' and 'Buram-3-ho') of Chinese cabbage in plastic pots in a greenhouse. We evaluated effects of bacterial strains on plant growth-promotion and mitigation of heat and drought stresses; the role of exopolysaccharides as one of bacterial determinants on alleviating stresses; biocontrol activity against soft rot caused by Pectobacterium carotovorum subsp. carotovorum PCC21. Strains H26-2 and H30-3 significantly increased fresh weights compared to a $MgSO_4$ solution; reduced leaf wilting and promoted recovery after re-watering under heat and drought stresses. Chinese cabbages treated with H26-2 and H30-3 increased leaf abscisic acid (ABA) content and reduced stomatal opening after stresses treatments, in addition, these strains stably colonized and maintained their populations in rhizosphere during heat and drought stresses. As well as tested bacterial cells, exopolysaccharides (EPS) of H30-3 could be one of bacterial determinants for alleviation of tested stresses in Chinese cabbages, however, the effects were different to cultivars of Chinese cabbages. In addition to bacterial activity to abiotic stresses, H30-3 could suppress incidence (%) of soft rot in 'Buram-3-ho'. The tested strains were identified as Bacillus aryabhattai H26-2 and B. siamensis H30-3 based on 16S rRNA gene sequence analysis. Taken together, H26-2 and H30-3 could be candidates for both plant growth promotion and mitigation of heat and drought stresses in Chinese cabbage.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.588-600
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• 2020

The effect of age (22, 30, 38, and 46 days) on Beijing duck breast myosin gels was investigated. The results showed that the water holding capacity (WHC) and gel strength were markedly improved at the age of 30 days. Differential scanning calorimetry suggested that the myosin thermal ability increased at the age of 30 and 38 days (p<0.05). A compact myosin gel network with thin cross-linked strands and small regular cavities formed at the age of 30 days, which was resulted from the higher content of hydrophobic interactions and disulfide bonds. Moreover, the surface hydrophobicity of myosin extracted from a 30-day-old duck breast decreased significantly under temperature higher than 80℃ (p<0.05). This study illustrated that myosin extracted from a 30-day-old duck's breast enhanced and stabilized the WHC, thermal stability and molecular forces within the gel system. It concluded that age is an essential influencing factor on the myosin thermal stability and gel quality of Beijing duck due to the transformation of fibrils with different myosin character.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.650-663
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• 2021

The objective of this study was to examine the relationship between meat quality attributes and the changes of sarcoplasmic protein acetylation and myofibrillar protein acetylation in lamb longissimus thoracis et lumborum muscles at different postmortem phases. Protein acetylation, color, pH, shear force, myofibril fragmentation index and cooking loss were measured. The total level of acetylated sarcoplasmic proteins showed a negative relation with pH, a positive relation with a^*, b^* and cooking loss at the pre-rigor phase. Sarcoplasmic proteins acetylation affected postmortem pH by regulating glycolysis, which in turn affects color and cooking loss. The total level of acetylated myofibrillar proteins showed a positive relation with shear force at the pre-rigor phase. Myofibrillar proteins acetylation affected meat tenderness by regulating muscle contraction. This study indicated that acetylation played a regulatory role of meat color, water-holding capacity, and tenderization process at early postmortem.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.402-407
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• 2003