• Nutrition Research and Practice
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• v.8 no.5
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• pp.509-515
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• 2014

BACKGROUND/OBJECTIVES: The root of Vitis amurensis Ruprecht, a sort of wild-growing grape, has been used in oriental medicine for treatment of skin ailments; however, its dermatological activity is not sufficiently understood. The aim of this study was to investigate tyrosinase inhibitory and anti-melanogenic activities of V. amurensis Ruprecht root methanol extract (VARM) in B16F10 mouse melanoma cells and to attempt to isolate and identify the active compound issued from VARM. MATERIALS/METHODS: Anti-melanogenic activity of VARM was analyzed in ${\alpha}$-melanocyte stimulating hormone (MSH)-stimulated B16F10 cells through evaluation of antioxidative activity as well as inhibited tyrosinase activity and melanin contents compared with those of kojic acid and arbutin. After anti-melanogenic analysis of VARM, serial fractionation, nuclear magnetic resonance (NMR), and thin layer chromatorgraphy (TLC) were applied for identification of active compounds contained in VARM. RESULTS: VARM significantly inhibited oxidative stress and tyrosinase activity and attenuated ${\alpha}$-MSH-induced melanin production in B16F10 cells. For isolation of active compounds, VARM was fractionated using a series of organic solvents, including dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc), and n-butanol (n-BuOH). Among fractions showing anti-melanogenic activity, the CH2Cl2 fraction induced the most potent attenuation of melanogenesis without cytotoxicity and the major compound in the $CH_2Cl_2$ fraction was identified as betulinic acid. Betulinic acid isolated from the $CH_2Cl_2$ fraction of VARM significantly attenuated ${\alpha}$-MSH-induced melanogenesis in a dose dependent manner, which was stronger than that of arbutin used as a positive control. CONCLUSIONS: These results indicate that VARM inhibits oxidative stress, tyrosinase activity, and ${\alpha}$-MSH-induced melanogenesis in B16F10 cells, due primarily to the active compound, betulinic acid, in the $CH_2Cl_2$ fraction.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.275-281
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• 2018

Pinus densiflora root (PDR) is used as a medicinal plant. In this study, we investigated whether the PDR extract has anti-inflammatory activities. Cell viability assays showed that the extract was not toxic toward RAW 264.7 cells at concentrations up to $10{\mu}g/mL$. At $10{\mu}g/mL$, the extract decreased nitric oxide (NO) content to 40% of the control level. The protein expression of inducible nitric oxide synthase (iNOS), which generates NO, decreased with increasing concentrations of the extract. Prostaglandin $E_2$ ($PGE_2$) levels were significantly inhibited by over 50% in the presence of $10{\mu}g/mL$ of the extract. The protein expression of cyclooxygenase-2 (COX-2), which generates $PGE_2$, decreased with increasing concentrations of the extract. Proinflammatory cytokines, such as tumor necrosis factor-alpha ($TNF-{\alpha}$), interleukin-6 (IL-6), and $IL-1{\beta}$, were detected in RAW 264.7 cells after lipopolysaccharide (LPS) treatment. The extract did not affect the levels of $TNF-{\alpha}$ and IL-6, but it significantly inhibited the level of $IL-1{\beta}$. It also completely inhibited the transcription of nuclear factor-kappaB ($NF-{\kappa}B$). These results indicate that the PDR extract reduces inflammatory response-related proteins, such as NO, $PGE_2$, iNOS, and COX-2, in LPS-induced RAW 264.7 cells via the regulation of $NF-{\kappa}B$. Consequently, we have provided a mechanism to explain the anti-inflammatory effect of the PDR extract; that is, it exerts such an effect by regulating $NF-{\kappa}B$. The PDR extract can therefore be considered as an effective anti-inflammatory agent.

• Journal of Radiation Industry
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• v.17 no.1
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• pp.61-67
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• 2023

A Study on the Introduction of Dose Constraints for Occupational Exposures: Focusing on Experts' Opinions by Field of Radiation Industry. The International Commission on Radiological Protection suggests Justification, Optimization, and Dose Limits as the three principles of radiological protection, among which, as a means of protection optimization, ICRP 103 recommends to set dose constraints. In this study, opinions are collected from experts in each category of radiation industries for stakeholder participation to qualify dose constraints. A guidance and questionnaire for analyzing the dose constraints have been developed for their collection, and opinions were collected from radiation protection experts in selected categories. 20 out of 22 experts, consisted with 91%, have assessed the dose constraints setting is necessary, and 2 experts, consisted with 9%, assessed it is unnecessary. The average of dose constraint presented by experts for RI production institutions is to be the highest level of 15.3 mSv, and light-water reactors (14.6 mSv), non-destructive inspection (14.4 mSv), heavy-water reactor and medical institutes (13.9mSv) is to be above the overall average dose constraint. In case of public institutions, the average dose constraint is to be 8.6mSv, and research institutions (8.8mSv), educational institutions (9.6 mSv), waste disposal sites (9.7 mSv), and general industries (10.6 mSv) are resulted to below the overall average dose constraint. As for the means of setting dose constraints, 8 experts out of 22 suggested setting dose constraints for each specific industry or task. And, 5 experts especially suggest setting dose constraints for the specific groups with relatively high exposure, such as workers with above the record levels. As a countermeasure for workers who exceed the dose constraints, 15 experts out of 22 expressed that the cause analyses for them and preparation for a plan of reducing them are necessary.

• Journal of Energy Engineering
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• v.20 no.1
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• pp.8-12
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• 2011

For reducing greenhouse gas emissions, the short-term strategy is of existing energy-efficient appliances to facilitate the spread of energy efficiency improvements to improve energy efficiency, energy saving projects that will include investments to enable. R&D is at the core of the long-term strategy. To reduce energy demand, the equipments and processes improved energy efficiency should be developed. In terms of energy supply, the policies for greenhouse gas reduction is to replace fossil fuels by expanding the supply of renewable energy such as solar, wind, geothermal, biomass and nuclear power as nearly zero-emission of greenhouse gas. In terms of energy consumption, measures to reduce greenhouse gas emissions is in line with the policy for efficiency improvement. The buildings & work-site of high-energy consumption in the building & Industry sectors, should implement a policy to strengthening the voluntary agreement on energy-saving facilities and expand to invest in energy saving facilities.

• Journal of the Korean Society for Nondestructive Testing
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• v.15 no.4
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• pp.561-567
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• 1996

As nuclear industry in Korea is being expended, the number of user for radioisotope and radiation generators has being remarkably increased. As a result, radiation shielding problem for radiation safety has rasied as a question of great interest nowaday. In this report, gamma scanning test (GST), one of the nondestructive test methods of radiation shielding material was introduced and the review of the test method and its application were described. In addition for accurate evaluation of the test result, necessary basic equipments for the test and for improvement of the equipment were suggested. If the effective test method described above were widely and properly applied by GST related companies, the technology would be used effectively, as one of the safe nondestructive test for radiation shielding material in future.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.1
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• pp.41-45
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• 2018

As the size of semiconductor chip shrinks, the electronic industry has been paying close attention to fan-out wafer level packaging (FO-WLP) as an emerging solution to accommodate high input and output density. FO-WLP also has several advantages, such as thin thickness and good thermal resistance, compared to conventional packaging technologies. However, one major challenge in current FO-WLP manufacturing process is to control wafer warpage, caused by the difference of coefficient of thermal expansion and Young's modulus among the materials. Wafer warpage induces misalignment of chips and interconnects, which eventually reduces product quality and reliability in high volume manufacturing. In order to control wafer warpage, it is necessary to understand the effect of material properties and design parameters, such as chip size, chip to mold ratio, and carrier thickness, during packaging processes. This paper focuses on the effects of thickness of chip and molding compound on 12" wafer warpage after PMC of EMC using finite element analysis. As a result, the largest warpage was observed at specific thickness ratio of chip and EMC.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.166-171
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• 2004

Since early 1950's fracture mechanics has brought significant impact on structural integrity assessment in a wide range of industries such as power, transportation, civil and petrochemical industries, especially in nuclear power plant industries. For the last two decades, significant efforts have been devoted in developing defect assessment procedures, from which various fitness-for-purpose or fitness-for-service codes have been developed. From another aspect, recent advances in IT (Information Technologies) bring rapid changes in various engineering fields. IT enables people to share information through network and thus provides concurrent working environment without limitations of working places. For this reason, a network system based on internet or intranet bas been appeared in various fields of business. Evaluating the integrity of structures is one of the most critical issues in nuclear industry. In order to evaluate the integrity of structures, a complicated and collaborative procedure is required including regular in-service inspection, fracture mechanics analysis, etc. And thus, experts in different fields have to cooperate to resolve the integrity problem. In this paper, an internet-based cooperative system for integrity evaluation system which adapts IT into a structural integrity evaluation procedure for reactor pressure vessel is introduced. The proposed system uses Virtual Reality (VR) technique, Virtual Network Computing (VNC) and agent programs. This system is able to support 3-dimensional virtual reality environment and to provide experts to cooperate by accessing related data through internet.

• Journal of Energy Engineering
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• v.11 no.4
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• pp.370-379
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• 2002

In the Korean electricity supply structure, the role of nuclear power generation is essential. But, the delaying of radioactive waste management program induces negative impact to the stable electricity supply. Despite the continuing endeavors of Korean Government and nuclear power industry, radioactive waste management program of Korea is experiencing a continuing setback. In this background, the study examined the past and current policy and recommends that; Long term safety assurance should be the prime objective of radioactive waste management; Siting process should be transparent and opened to the public with the involvement of safety regulatory authority; A new neutral organization which has no conflicts of interest with any other existing organizations should be established to coordinate and manage the R&D programs.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.275-282
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• 2010

Chloroplast transformation in higher plants offers many attractive advantages over nuclear transformation, including a high-level accumulation of foreign proteins, multi-gene expression in single transformation event via transgene stacking in operons and no position effect due to site-specific integration of transgenes by homologous recombination. Most importantly, chloroplast transgenic plants are eco-friendly because their transgenes are maternally inheritance in most crop plants. However, chloroplast transformation system has limited success in crops alike nuclear transformation. In the past two decades, great progress has been made to overcome the limitations of chloroplast transformation, thus expending chloroplast bioreactor to several important crops including soybean, carrot, lettuce, and oilseed. Therefore, it has become possible that chloroplast transformation of crops can be used not only for the improvement of agronomic traits, but also for the production of vaccines and high valuable therapeutic proteins in pharmaceutical industry.

• Journal of Sericultural and Entomological Science
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• v.22 no.2
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• pp.8-12
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• 1981

Practical application of silkworm artificial diet is very desirable to save labour in sericultural industry as the problem of labour shortage is becoming serious in Korea. However, silkworms reared on the artificial diet are more susceptible to viruses than those reared on mulberry leaves because of the lower anti-viral activity of gut juice of silkworms grown on artificial diet compared with that of silkworms grown on mulberry leaves. In this study, authors investigated the varietal difference of silkworm larvae, Bombyx mori L., reared on artificial diet which contained 20 percent of dried mulberry powder, in the susceptibility to nuclear polyhedrosis virus (NPV). The results showed that there is no difference in susceptibility to NPV among tested varieties when high concentration of NPV was admitted to silkworm larvae, but varietal difference appeared in lower concentration admitted. Among 7 hybrids tested, Hansaeng 1${\times}$Hansaeng 2 was most resistant to NPV with an $LC_{50}$ of 2.7${\times}$10$\^$6/ and Jam 111${\times}$Jam 112 was also more resistant comparatively than other hybrids.