• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.361-376
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• 2020

Atacamite and Verdigris were studied material scientific properties and durability that are used for traditional green pigment in traditional art painting work and Dancheong. As a result of ingrediant analysis, K-AA and K-VA identified Atacamite and Hoganite (or Verdigris) respectively. In order to find a factor of depressing the stability of pigment, we examined UV radiant exposure test, CO2/NO2 gas corrosion test and salt spray test. Salt spray test damaged both samples which were formed salt particle on the surface of the samples and it makes color disability. Furthermore, the results of gas corrosion test that both pigments change color enough to be perceived by the naked eyes showed that an air pollutant NO2 gas is also considered to be a major damage factor. In the case of K-VA, Hoganite that is main component of sample changes Tenorite with turn black after accelerated UV radiant exposure test. The consequences of the atmospheric environment effect test of the two pigments, K-VA showed relatetively weaker than K-AA.

• Journal of Apiculture
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• v.32 no.3
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• pp.269-273
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• 2017

We investigated whether purified bee venom increases the enzymatic activity of the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). ADH and ALDH assay were tested by in vitro kits. The purified bee venom was assayed by ultra performance liquid chromatography, The contents of melittin, apamin and phospholipase A2, as main component of purified bee venom, were 63.9%, 2.3%, and 10.9%, respectively. The ADH and ALDH acitivity of purified bee venom(at 1mg/ml) were $88.6{\pm}7.34%$ and $94.6{\pm}0.57%$, respectively compared with positive control at 2mg/ml. These results showed that purified bee venom induces the activity of ADH and ALDH which reduce the aldehyde concentration in the blood, suggesting the possibility of purified bee venom as resource of medicine or functional beverage for hangover relieving.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.774-780
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• 2021

The auxiliary power unit (APU) of a rotorcraft starts the engine during operation/flying. The APU is composed of a gas turbine engine type. The starting principle of the component is that the electric start motor generates the power required for starting by rotating the shaft. In this study, quality improvement was performed by applying an over-running clutch (ORC) between the APU and the starter motor to secure the operability of the starter motor of the APU mounted on the rotorcraft. The starter motor has the main role of starting the APU, but during operation, it is rotated without load by the rotational force of the APU gear shaft, resulting in friction at the brush. This phenomenon causes abrasion of the brush of the starter motor. Consequently, when the APU operation time increases, the brush life decreases, and the operability of the APU is affected. In this study, an ORC that separates the interlocking between the start motor brush abrasion and the APU operation time was applied to improve the operability/durability of the APU starter motor. The effect was verified through a test, and the technical feasibility of the design change was analyzed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.1
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• pp.85-92
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• 2021

The stratum corneum is formed from keratinocytes and intercellular lipids, with ceramide as the main component of intercellular lipids. Ceramides are one of the important components of the intercellular lipids to form a lamellar structure, but they are insoluble and therefore are not suitable for direct application to the skin. Thus, it was intended to apply ceramide to the formulation of pluronic lecithin organogel (PLO gel), which received constant attention among drug delivery systems. A suitable oil for formulation was selected and a PLO gel containing ceramide was manufactured. Liquid crystal formation and variation were observed using polarized microscopes, and viscoelastic analysis was performed to find out the viscoelastic behavior of the PLO gel. Small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) analysis were performed to confirm the structures in the formulation. Results showed that the size and stability of the liquid crystal differed depending on the content ratio of ceramide and lecithin in the PLO gel containing ceramide. Furthermore, viscoelastic analysis showed the stability of the formulation, and SAXS/WAXS analysis confirmed that the PLO gel without ceramide had hexagonal structure of the quadrilateral system array, and the PLO gel with ceramide had the lamellar structure of the quadrilateral system array.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.211-217
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• 2020

Technology planning in the defense field aims to develop core technologies in order to develop weapon systems to satisfy the force integration period by researching and analyzing necessary technologies for weapon systems. In the past, core technology development projects were conducted by deriving core technology based on the main required operational capability. But in this case, there is the limitation that technologies which are necessary to develop weapon systems but do not directly affect required operational capability, such as system integration technologies, are not considered. In this paper, we propose a work breakdown structure-based technology research and analysis methodology that prevents vacant technologies by identifying core technologies that must be secured for the development of weapon systems at the component level. With the proposed methodology, it is possible to identify technologies that must be acquired to realize the required operational capability of systems or which must be secured even they do not affect the required operational capability.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.465-482
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• 2021

Lipids, which along with carbohydrates and proteins are among the most important nutrients for the living organism, have a variety of biological functions that can be applied widely in biomedicine. A fatty acid, the most fundamental biological lipid, may be classified by length of its aliphatic chain, and the short-, medium-, and long-chain fatty acids and each have distinct biological activities with therapeutic relevance. For example, short-chain fatty acids have immune regulatory activities and could be useful against autoimmune disease; medium-chain fatty acids generate ketogenic metabolites and may be used to control seizure; and some metabolites oxidized from long-chain fatty acids could be used to treat metabolic disorders. Glycerolipids play important roles in pathological environments, such as those of cancers or metabolic disorders, and thus are regarded as a potential therapeutic target. Phospholipids represent the main building unit of the plasma membrane of cells, and play key roles in cellular signaling. Due to their physical properties, glycerophospholipids are frequently used as pharmaceutical ingredients, in addition to being potential novel drug targets for treating disease. Sphingolipids, which comprise another component of the plasma membrane, have their own distinct biological functions and have been investigated in nanotechnological applications such as drug delivery systems. Saccharolipids, which are derived from bacteria, have endotoxin effects that stimulate the immune system. Chemically modified saccharolipids might be useful for cancer immunotherapy or as vaccine adjuvants. This review will address the important biological function of several key lipids and offer critical insights into their potential therapeutic applications.

• Conservation Science in Museum
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• v.26
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• pp.119-142
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• 2021

The gilt-bronze-and-silver shoes, excavated from the Tomb of King Muryeong, revealed many defective parts, which constantly raised in-depth re-investigation and reporting. In that point, scientific treatment and analysis were conducted to investigate the manufacturing techniques applied. The conservation treatment was carried out with an emphasis on the restoration of the original form and joining parts. As a result, the upper part of the right shoe and some part of the back heel were joined, confirming the joining method and the number of rivet used for instep bonding. From the component analysis, it is presumed that the outer plate was gilded with mercury amalgam on pure copper, and pure silver was used for the inner plate. The main pattern of the gilt-bronze-and-silver shoes includes designs of phoenix, lotus, and six-petal flower, while the lotus pattern is high in terms of ratio. Thus, youngnaksa(twisted gilt-bronze thread), geumdongsa(gilt-bronze thread), wondujeong (rivet), and samyeonjeong(quadrangular cleats) were used for bonding each plate. Twisted gilt-bronze thread was used to join the inner and outer plates, while the center and rear of the inner plate were combined with only gilt-bronze threads. From the fact, it is presumed that the joining method was different whether the function was decoration or just bonding. Regarding the manufacturing process, traces of burnishing were confirmed on the outer surface of the gilt-bronze and silver shoes, but no burnishing traces were identified on the inner surface of the silver plate, which is likely to prove more importance put on the finishing of the outer plates rather than that of the inner.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.114-120
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• 2022

In this study, a comparative dissolution experiment was conducted between an immediate-release and a controlled-release vitamin C tablet applied with a technology to control the dissolution of vitamin C to maintain the vitamin C level in the human body. In order to confirm the dissolution rate (%) of vitamin C tablets, HPLC determination was conducted based on the dissolution test methods in the 'Korean Pharmacopoeia (No. 2020-88),' 'Guidelines on Specifications of Dissolution Tests for Oral dosage Forms,' and 'Standard and Specifications for Health Functional Foods (No. 2020-63)' from Ministry of Food and Drug Safety (MFDS). In addition, the dissolution pattern between the immediate-release tablet and the controlled-release tablet was comparatively analyzed. The analysis result confirmed that the immediate-release vitamin C tablet was 100% dissolved after 45 minutes, while the controlled-release vitamin C tablet was 100% dissolved after 480 minutes (8 hours). Furthermore, the dissolution rate (%) at 60 minutes was slower than that of the immediate-release vitamin C tablet. Based on these results, this study confirmed that the dissolution rate (%) test and development of controlled-release tablets containing vitamin C as the main component a re possible.

• Korean Journal of Plant Resources
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• v.35 no.2
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• pp.362-371
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• 2022

This study was conducted to analyze the fragrance characteristics of Cymbidium 'Saelbit' and 'Midan' according to floral organs. As test materials, full bloom flowers were divided into four organs: sepal, petal, labellum, and column. Using the gas chromatography (GC) based electronic nose, fragrance patterns, intensity, and volatile components were analyzed. Principle component analysis (PCA) and discriminant factorial analysis (DFA) plots by electronic nose data showed that volatiles of both cultivars have a distinct difference in fragrance patterns according to the floral organs, and the value of fragrance distance and pattern discrimination index (PDI) between samples was significantly high between control and sepals in both cultivars. Among the main fragrance components, several components including nootkatone were detected in both cultivars and all floral organs. However, few components such as decane were found in specific cultivar or floral organs. These results will provide useful information to select suitable materials with desired fragrance and to enhance the utilization of domestic Cymbidium cultivars. In addition, considering the recent negative perception of artificial ingredients and the growing demand for natural materials, continuous researches on scent properties of promising cultivars are required.

• The Journal of Korean Medicine
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• v.43 no.2
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• pp.1-7
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• 2022

Objectives: Bee venom (BV) is a widely used therapy in Traditional East Asian Medicine (TEAM). We previously reported that BV was clinically effective for treating Parkinson's disease, that phospholipase A₂ (PLA₂) was the main component of BV, and that it induced regulatory T cells (Tregs) by binding CD206 on dendritic cells (DCs). Therefore, we aimed to reconfirm our findings in human blood samples and investigate the relationship between CD206⁺ DCs and clinical syndrome differentiation in TEAM. Methods: We surveyed 100 subjects with questionnaires on cold-heat patternization and obtained their blood samples. The obtained human peripheral blood monocytes (hPBMCs) were washed with phosphate-buffered saline (PBS). After resuspension with ex vivo media, numbers of cells were counted. Tregs were counted after culturing the samples in a 37℃ CO₂ incubator for 72 h. Results: We divided the subjects into a relatively high CD206⁺ group or a relatively low CD206⁺ group. The heat factor scores of high CD206⁺ group were significantly higher than that of low CD206⁺ group (high vs low: 239.2 ± 54.1 vs 208.4 ± 55.1, p=0.023). After culturing with PLA₂, Tregs increased in the high CD206⁺ group but decreased in the low CD206⁺ group. Conclusion: In this study, we reconfirm that CD206⁺ DCs induced Treg differentiation by incubating human blood samples with PLA₂ and that they showed an association with syndrome differentiation, especially with heat patterns, in TEAM. A heat pattern in TEAM might be one indication for PLA₂ therapy because its score was elevated in the high CD206⁺ group.