• Natural Product Sciences
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• v.22 no.3
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• pp.201-208
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• 2016

Here in this study, we investigated the lifespan-extending effect and underlying mechanism of methanolic extract of Moringa olelifa leaves (MML) using Caenorhabditis elegans (C. elegans) model system. To define the longevity properties of MML we conducted lifespan assay and MML showed significant increase in lifespan under normal culture condition. In addition, MML elevated stress tolerance of C. elegans to endure against thermal, oxidative and osmotic stress conditions. Our data also revealed that increased activities of antioxidant enzymes and expressions of stress resistance proteins were attributed to MML-mediated enhanced stress resistance. We further investigated the involvement of MML on the aging-related factors such as growth, food intake, fertility, and motility. Interestingly, MML significantly reduced growth and egg-laying, suggesting these factors were closely linked with MML-mediated longevity. We also observed the movement of aged worms to estimate the effects of MML on the health span. Herein, MML efficiently elevated motility of aged worms, indicating MML may affect health span as well as lifespan. Our genetic analysis using knockout mutants showed that lifespan-extension activity of MML was interconnected with several genes such as skn-1, sir-2.1, daf-2, age-1 and daf-16. Based on these results, we could conclude that MML prolongs the lifespan of worms via activation of SKN-1 and SIR-2.1 and inhibition of insulin/IGF pathway, followed by DAF-16 activation.

• Journal of Welding and Joining
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• v.31 no.5
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• pp.54-58
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• 2013

Joint properties of vehicle ECU (Electric Control Unit) module which was manufactured by using Sn-Cu-Cr-Ca alloy were investigated. A new solder which has a middle melting temperature about $231^{\circ}C$ was fabricated as the type of 300um solder ball and paste type. The prototype modules were made by reflow process and measured spreadability, wettability shear strength and estimated interface reaction. The spreadability of the alloy was about 84% from the measurement of contact angle of the solder ball and the wetting force was measured 2mN. The average shear strength of the module which was manufactured by using the solder paste, was 1.9 $kg/mm^2$. Also, the thickness of IMC(intermetallic compound) was evaluated with various aging temperature and time in order to understand Cr effect on Sn-0.7Cu solder. $Cu_6Sn_5$ IMC was formed between Cu pad and the solder alloy and the average thickness of the $Cu_6Sn_5$ IMC was measured about 4um and it was about 50% of thickness of $Cu_6Sn_5$ IMC in Sn-0.7Cu. It is expected to have a positive effect on reliability of the solder joint.

• Journal of the Korean Society for Heat Treatment
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• v.5 no.2
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• pp.103-110
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• 1992

This study is aimed to investigate the effect of various thermomechanical treatments($T_6$, $T_8$ and ITMT) on the microstructure and mechanical properties of an Al-Cu-Li-Ag-Mg-Zr alloy (Weldalite 049) which has been known to strong natural aging response, good weldablity and high strength in $T_6$ sand $T_8$ temper. This experiment was performed by means of differential scaning calorimetry, tensile test, optical and transmission electron microscopy. The tensile strength in the peak aged condition shows 620, 650 MPa in $T_6$ and $T_8$(40% cold work), respectively. Also, The tensile strength is increased with cold working in $T_8$ but decreased at 60% cold working. However, the tensile strength of the intermediate thermomechanical treated speciman(ITMT) is lower than that of $T_6$ temper about 20% but the elongation is higher than two times. It might be predicted that the ITMT is effective processing to improve the toughness of this alloy. In $T_6$, $T_8$ and ITMT, the major strengthening phase is $T_1(Al_2CuLi)$ phases. and the fine $T_1$ phase which are homogeneously precipited in matrix was observed much more in $T_8$ than $T_6$ and ITMT.

• 보존과학연구
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• s.33
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• pp.19-32
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• 2012

Paper relics, which are made of natural ingredients, are more likely to be damaged by a compendium of complicated causes (e.g., physical, chemical, and biological causes) rather than by a sole cause. In December 2009, Culture Heritage Conservation Science Center discovered several damages in paper relics related to Chungmugong Yi Sunsin, and requested for conservation treatment from the Hyeonchungsa Shrine office. By conducting a comprehensive research to determine the damage level of each artifact, the center was able to establish a proper conservation method, and for two years after its completion of such research in 2010, it has been conducting treatment. This study suggests the proper ways to select adequate conservation treatment based on the type of paper relics - Documents and Books - through the case of artifacts related to Chungmugong Yi, Sunsin. Even though the conservation treatment on paper relics can suppress damaging speed and prevent another damages, it is impossible to stop aging process of relics. Therefore regular inspection is essential for prevent second damage.

• Membrane Journal
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• v.22 no.5
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• pp.342-351
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• 2012

In this study, PTMSP[poly(1-trimethylsilyl-1-propyne)]/PDMS[poly(dimethylsioxane)]-NaY zeolite and PTMSP/PDMS-NaA zeolite composite membranes were made to incorporate zeolite into PTMSP/PDMS graft copolymer in order to improve the selectivity and thermal stability, the drop of permeability by physical aging effect during long period of time for the PTMSP membrane. To investigate the physico-chemical characteristics of composite membranes, the analytical methods such as FT-IR, $^1H$-NMR, TGA, SEM, and GPC have been utilized. The gas permeability and selectivity properties of $H_2$ and $N_2$ were evaluated. The permeability of the PTMSP/PDMS-NaY zeolite and PTMSP/PDMS-NaA zeolite composite membranes than PTMSP/PDMS graft copolymer membrane increased, increased as zeolite content increased. On the contrary, the selectivity ($H_2/N_2$) of the composite membranes decreased as zeolite content increased. PTMSP/PDMS-NaA zeolite composite membrane showed better permeability and separation factor than PTMSP/PDMS-NaY zeolite composite membrane.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.883-892
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• 2018

Probiotics, including Enterococcus faecium, confer a health benefit on the host. An Enterococcus strain was isolated from healthy chicken cecum, identified as E. faecium by 16S rDNA gene sequence analysis, and designated as E. faecium L11. To evaluate the potential of E. faecium L11 as a probiotic, the gastrointestinal tolerance, immunomodulatory activity, and lifespan extension properties of the strain were assayed. E. faecium L11 showed >66% and >62% survival in artificial gastric juice (0.3% pepsin, pH 2.5) and simulated small intestinal juice (0.5% bile salt and 0.1% pancreatin), respectively. Heat-killed E. faecium L11 significantly (p < 0.05) increased immune cell proliferation compared with controls, and stimulated the production of cytokines (IL-6 and $TNF-{\alpha}$) by activated macrophages obtained from ICR mice. In addition, E. faecium L11 showed a protective effect against Salmonella Typhimurium infection in Caenorhabditis elegans. In addition, feeding E. faecium L11 significantly (p < 0.05) extended the lifespan of C. elegans compared with the control. Furthermore, genes related to aging and host defense were upregulated in E. faecium L11-fed worms. In conclusion, E. faecium L11, which prolongs the lifespan of C. elegans, may be a potent probiotic supplement for livestock.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.38-43
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• 1990

Effects of concentration (5-8%, db) and heating temperature $(80^{\circ}C-95^{\circ}C)$ on rheological of mungbean starch were examined. The pasting curve by amylograph revealed no peak viscosity and the viscosity continued to increase during cooking, regardless the starch concentrations. Mungbean starch paste showed a pseudoplastic flow behavior with yield stress. The consistency index of paste increased as the heating temperature was raised at a given concentration. However, flow behavior index showed opposite trend. The percent sag of starch gel stored at $4^{\circ}C$ decreased with the increase of concentration and heating temperature. The firmness of fresh gel prepared from 7 and 8% starch suspensions by heating at $95^{\circ}C$ for 15 min with amylograph was about 2-times higher than that of 6% gel. However, the time constant, reciprocal of rate constant, of starch gels during aging at $4^{\circ}C$ was not significantly influenced by concentrations and heating temperatures.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.400-406
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• 2014

Apios (Apios americana Medikus) belongs to Leguminosae and is called 'American groundnut', 'Potato bean', and 'wild bean'. Apios is native to the Northern United States but is not widely distributed in Korea. In this study, cross-linked apios starch was prepared by reaction with epichlorohydrin, followed by characterization. FT-IR spectroscopy confirmed the degree of cross-linking of apios starch. X-ray diffraction patterns of native apios showed typical 'A' type as peaks at 15.1, 17.1, 17.9 and $23.2^{\circ}$, and cross-linking did not affect relative crystallinity and X-ray diffraction patterns of the starch. Scanning electron micrographs showed that apios starch granules were smooth with a globular shape, and there was little damage to starch granules after cross-linking. The lightness value of cross-linked apios starch was lower than that of native apios starch, whereas the redness value was not significantly different between cross-linked apios starch and native apios starch. Blue value showed that cross-linking of starch did not affect the iodine reaction of starch.

• Journal of the Korean Chemical Society
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• v.31 no.1
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• pp.110-117
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• 1987

For the preparation of linear low density polyethylene (LLDPE), the copolymerization of ethylene and 1-butene was carried out with various catalysts of titanium alkoxidealkylaluminum compound in slurry phase. The effects of catalyst components, aging time, concentration of catalyst components, polymerization time and temperature on the catalytic activity and copolymer composition were examined. The properties of copolymer obtained were also considered with the correlation to the 1-butene contents. It has been found that the titanium tetra-n-butoxide-diethylaluminum chloride catalyst system was the most suitable for the production of LLDPE with higher catalytic activity, more 1-butene content and less soluble parts. The density, glass transition temperature, melting point and heat of fusion of copolymer were decreased with increasing 1-butene contents.

• Culinary science and hospitality research
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• v.4
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• pp.249-269
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• 1998

What satisfies the desire of human beings about taste most easily is sweet taste, and it has seemed that the pronoun of sweet taste is sugar. Sugar is used in confectionery and bread-making essentially, and it has influence on the structure and touch of baked confectionery. In addition, if we soften the and apply heat, coloring is made. Thus, it colors good. It doesn't have a sweet taste, but it has the effect to emit fragrance variously, balance and soften the product. The kinds of sugar are very diverse, and it is sugar to be referred to as white sugar is used most frequently. In this study, this researcher examined the classification of physicochemical property and melting point etc. of sugar in confectionery and bread-making through theoretical study, about the simple classification of sugar. In addition, this researcher approached about the role of sugar in confectionery and bread-making and about the influence to have when it is more or less than proper quantity, centering around function. As the result, this researcher extracted the importance of sugar in confectionery and bread-making. It means that the increase of 5% of sugar quantity decreases the absorption quantity of moisture by 1% in bread-making and that the excess of 8% of sugar slow the action of yeast in straight method. Besides, there are the properties such as absorptive property, permeability, storage nature, aging prevention of starch, oxidation restraint of oils and fats, the gelation action of pectin, the fermentation acceleration of yeast, and the emulsification-maintaining-nautre and antiseptics effect of fat-soluble material. And in confectionery, sugar makes fragrance and peel color, increases the storage nature with moisture maintenance and has the softening effect. So, it is considered that the attitude to study and make efforts continuously on the basis of the role of sugar will have to be unfolded in confectionery and bread-making.