• Journal of Korea Foundry Society
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• v.6 no.1
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• pp.12-19
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• 1986

This study was undertaken to understand the formation mechanism of the hard spots in high strength brass. To investigate the behavior of the hard spots in the isothermal liquid state with varying silicon content, the rapidly quenched specimens were obtained by suctioning the melt into the silica tube and water quenching. To examine the growth process of the hard spots with holding time, the unidirectional solidification technique was used. The results of this study are summarized as follows: 1) With the addition of Fe in order to get the effects of grain refinement in high strength brass, the two different type of Fe-rich phases are occurred, which are defined as dendritic and globular phase. The chemical composition of the globular phase was different from that of the dendritic phase in that the globular phase contained Si. 2) With increasing Si content, the Fe-rich phase had a tendency to form globular phase. 3) As the holding time increased in the liquid state, globular was also prone to coalesce. The further growth of globular phase to large size was due to reducing the interfacial energy. 4) The primary phase of copper alloy was nucleated preferentially on the dendritic phase. It was noticeable that the dendritic phase acted as a grain refiner. However, the agglomerate (hard spots) which was composed of the globular phase decreased the mechanical properties of high strength brass. 5) Once the hard spots formed in the high strength brass casting, it was very difficult to remove them. This is due to the fact that their meting temperature is higher than the pouring temperature of high strength brass.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.221-226
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• 2016

A new type of doenjang was manufactured by mixing soaked soybean, koji (Rhizopus oryzae), cheonggukjang (Bacillus amyloliquefaciens MJ1-4 and B. amyloliquefaciens EMD17), and Pichia farinosa SY80 as a yeast, salt, and water, followed by fermentation with koji that was made by fermenting whole wheat with R. oryzae. The mixed culture doenjang was designed to have a more palatable flavor and stronger biological activities than the conventional product. The extract of mixed culture doenjang showed higher antioxidant activity than the commercial doenjang as evaluated by the ferric reducing antioxidant power assay although it was not significantly different from the commercial product in 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activities. Further, the mixed culture doenjang reduced intracellular reactive oxygen species levels and protected cells from glutamate-induced cytotoxicity more efficiently in human hippocampal HT22 neuroblastoma cells than the commercial doenjang. In conclusion, a newly-developed mixed culture doenjang had a strong antioxidant activity in vitro and cultured cell model systems, exhibited a potential to prevent oxidative stress-associated disorders although animal and clinical studies are needed to confirm its in vivo efficacy.

• Journal of the Korean GEO-environmental Society
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• v.21 no.2
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• pp.5-13
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• 2020

The relief wells have been studied to be effective in seepage control in small dams such as agricultural dams. However, quantitative studies on the effects of the relief well are rare and there is no design standard also. To quantitatively analyze the effects of the seepage control in small dams, the research of up-lift pressure influencing the toe of dam body was conducted by seepage analysis, which investigates the behavior characteristics, according to the conditions of dam and foundation. The effect of seepage control was studied by analyzing the reduction effect of up-lift pressure at foundation ground of the toe of downstream dam slope depending on the installation of the relief well. As a result, it was found that the relief wells are effective in reducing the pore water pressure in the foundation, which can cause piping and sliding failure.

• Culinary science and hospitality research
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• v.13 no.2
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• pp.254-259
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• 2007

The control of enzymic browning in potato slices by the use of citrate and phosphate buffer at different pH values and concentration was investigated. Minimally processed potatoes were stored at $5^{\circ}C$ and $20^{\circ}C$ followed by dipping in distilled water, citrate buffer (pH $3.0{\sim}5.0$) and phosphate buffer (pH $5.0{\sim}7.0$). The color characteristic was measured after storage at $5^{\circ}C$ and $20^{\circ}C$ for 24 hours. Treatment effectiveness was greatly improved by reducing pH and temperature. The citrate buffer was more effective than phosphate buffer in the browning inhibitory capacity. The citrate buffer (pH 3.0) showed the most anti-browning effect in this condition and more effective inhibition of browning by increasing concentration of treatment solution. The phosphate buffer (pH 5.0) treatment showed more effectiveness than concentration of 0.5 M of citrate buffer treatment.

• Mycobiology
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• v.39 no.3
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• pp.187-193
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• 2011

Botryosphaeran, a water-soluble exopolysaccharide of the ${\beta}-(1{\rightarrow}3;1{\rightarrow}6)$-D-glucan type that has been isolated from the culture medium of Botryosphaeria rhodina MAMB-05 grown in submerged fermentation using glucose as the sole carbon source, was previously demonstrated to be non-genotoxic in peripheral blood and bone marrow, and exhibited strong anticlastogenic activity. In the present study, the effects of botryosphaeran were investigated in streptozotocin-induced diabetic rats as well as in high-fat diet-fed hyperlipidemic Wistar rats. The plasma glucose level was reduced by 52% in the diabetic group of rats after administration of 12 mg botryosphaeran/kg body weight of the rats (b.w.)/day by gavage over 15 days. A reduction in the median ration intake was accompanied by an increase in the median body weight gain, as well as the efficiency of food conversion. These results demonstrate that botryosphaeran has protective effects by reducing the symptoms of cachexia in Diabetes mellitus. Botryosphaeran administered by gavage at a concentration of 12 mg botryosphaeran/kg b.w./day over 15 days also reduced the plasma levels of total cholesterol and low density lipoprotein-cholesterol by 18% and 27%, respectively, in hyperlipidemic rats. Based on these findings, we conclude that botryosphaeran possesses hypoglycemic and hypocholesterolemic properties in conditions of diabetes mellitus and hyperlipidemia, respectively, and may be used as an oral anti-diabetic agent.

• Polymer(Korea)
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• v.35 no.1
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• pp.13-16
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• 2011

In this study, the hydrogels composed of polyvinylpyrrolidone (PVP), ${\kappa}$-carrageenan (${\kappa}C$), and 1,2-hexanediol (HD) were prepared by ${\gamma}$-ray irradiation. The radiation dose was 25 kGy and the concentration of ${\kappa}C$ was 3 wt%. The physical properties of the hydrogels were investigated as a function of the concentrations of PVP and HD. The gel content and the tensile strength increased with increasing PVP concentration due to the crosslinking between the pyrrolidone molecules and decreased with increasing HD concentration. The degree of swelling was inversely proportional to the gel content because the highly crosslinked hydrogels had a tighter structure, hence reducing their water absorption. The antibacterial tests indicated that the hydrogels containing HD had antibacterial activity.

• Animal cells and systems
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• v.1 no.1
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• pp.77-80
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• 1997

DOantrolene is a primary specific therapeutic drug for prevention and treatment of malignant hyperthermia symptoms. The mechanisms underlying the therapeutic effects of the drug are not well understood. The present study aimed at the characterization of the effects of azumolene, a water soluble dantrolene analogue, on ryanodine binding to sarcoplasmic reticulum (SR) from normal and malign::lnt hyperthermia susceptible (MHS) swine muscles. Characteristics of $[^3H]ryanodine$ binding were clearly different between the two types of SR. Kinetic analysis of eH]ryanodine binding to SR in the presence of $2{\mu}M$ $Ca^{2+}$ showed that association constant $(K_{ryanodine}_7$ is significantly higher in MHS than normal muscle SR $(2.83 vs. 1.32{\times}10^7 M^{-1}$, whereas the maximal ryanodine binding capacity $(B_{max})$ is similar between the two types of SR. Addition of azumolene $(e.g. 400{\mu}M)$ did not significantly alter both $K_{ryanodine}$ and $B_{max}$ of $[^3H]$ryanodine binding in both types of SR, indicating that the azumolene effect was not on the ryanodine binding sites. Addition of caffeine activated $[^3H]$ ryanodine binding in both types of SR, and caffeine sensitivity was significantly higher in MHS muscle SR than normal muscle SR $(K_{caffeine}:3.24 vs. 0.82 {\times} 10^2 M^{-l}). Addition of azumolene $(e.g.400{\mu}M)$ decreased Kcaffeine without significant change in $B_{max}$ in both types of SR suggesting that azumolene competes with caffeine binding site(s). These results suggest that malignant hyperthermia symptoms are caused at least in part by greater sensitivity of the MHS muscle SR to the $Ca^{2+}$ release drug(s), and that azumolene can reverse the symptoms by reducing the drug affinity to $Ca^{2+}$ release channels.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.4
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• pp.535-542
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• 2012

The purpose of this study was to evaluate the quality characteristics and antioxidant activity of chocolate added with Rehmannia Radix Preparata (R. Radix Preparata) concentrate (0, 3, 6 and 9%). As the amount of R. Radix Preparata concentrate increased, water content significantly. The pH of chocolate decreased significantly as R. Radix Preparata concentrate increased, but the acidity of chocolate increased. Sugar concentration and reducing sugar contents also increased according to the amount of R. Radix Preparata concentrate. The L(lightness), a(redness) and b(yellowness) values significantly decreased as R. Radix Preparata concentrate increased. However, texture was not significantly different among the treatments. As the amount of R. Radix Preparata concentrate increased, DPPH radical scavenging and hydroxyl radical scavenging activities increased. In the results of the sensory evaluation, scores of color, taste, flavor, texture, and overall acceptability were the highest in chocolate added with 6% R. Radix Preparata concentrate. From these results, it was suggested that the optimum addition amount of R. Radix Preparata concentrate to chocolate is 6%.

• Journal of Korean Medical classics
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• v.28 no.4
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• pp.99-119
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• 2015

Objectives : This study aims to compare and analyze the contents and logic of Lee Jema's chest bind theory of the Soyang pattern with that of the traditional perspective since Shanghanlun, and to further investigate its underlying meaning and evaluate its value. Methods : Study chest bind related arguments of Lee through historical, demonstrative and positive investigation. First, contrast related texts starting from Shanghanlun, followed by reasoning based on general medical logic. Finally review clinical case studies from texts and papers for verification. Results : According to Lee, the key to diagnosis and treatment in preventing major chest bind which is a severe condition in the exterior cold pattern of the Soyang constitution, is to disperse fluid bind using GanSui(甘遂) in the water counterflow and vomiting(水逆嘔吐) stage prior to the major chest bind symptoms of stiffness and pain in the lower chest(心下硬痛), and reducing phlegm-rheum using DoJeokGangGiTang(導赤降氣湯) in the beginning stages of chest bind. HyeongBangDoJeokSan(荊防導赤散) is the main formula in treating phlegm-rheum, a causal factor to chest bind, modified according to the 'treat the three burners separately(三焦分治)' theory of the DaoChiSan(導赤散) section in WanBingHuiChun (萬病回春) to accomodate the Soyang constitution. Conclusions : If we follow Lee's diagnosis and treatment system on chest bind, it will allow us to diagnose chest bind in the earlier stages and secure safe treatment.

• The Korean Journal of Food And Nutrition
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• v.21 no.2
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• pp.210-217
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• 2008

This study evaluated the hypolipidemic effects of Eleutherococcus senticosus combined with several oriental medicinal herbs. In addition, it addressed whether consuming a diet of healthy food along with a daily supplement of this composite could affect the health status of individuals suffering from diet-related disease such as obesity and hyperlipidemia. The effects of the combined medicinal herbal extracts(MHE) extracted with hot water on reducing serum lipids and improving blood parameters were examined in rats fed a high-fat diet for 5 weeks. Sprague-Dawley rats were randomly assigned to 4 groups: basal diet only(BDG), high fat diet without MHE(FCG), high fat diet and 10% MHE(F10E) and high fat diet and 20% MHE(F20E). Serum lipid contents and blood variables were examined after the experimental period. The results of were as follows. The hematological data for the 4 groups were similar indicating no significant differences. There were moderate level of serum GOT activity in the F10E and F20E groups as compared to the FCG group. Total cholesterol, LDL-cholesterol, triglyceride in serum and the atherogenic index were remarkably reduced in the MHE-supplemented groups as compared to the control group. However, F10E and F20E groups had significantly higher HDL-cholesterol levels than the control group. These results imply that combination of several medicinal herbal extracts could be used to reduce of serum lipid concentrations. The data from this study will be used as basic information with the field of functional food research to address how we can apply oriental medicinal resources to foods. Such research currently drawing considerable attention world-wide.