• Bulletin of the Korean Mathematical Society
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• v.50 no.1
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• pp.57-71
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• 2013

In this paper, we establish the existence of at least three solutions to a Navier boundary problem involving the ($p_1$, ${\cdots}$, $p_n$)-biharmonic systems. We use a variational approach based on a three critical points theorem due to Ricceri [B. Ricceri, A three critical points theorem revisited, Nonlinear Anal. 70 (2009), 3084-3089].

• Food Science of Animal Resources
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• v.32 no.3
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• pp.346-353
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• 2012

This study was carried out in order to investigate the relationship of antioxidant enzyme activity, lipid oxidation, and aroma pattern of Hanwoo (Korean cattle) beef for 8 d at $15^{\circ}C/RH$ 100% under 0% $O_2$/20% $CO_2/80%\;N_2$, 25% $O_2$/20% $CO_2/55%\;N_2$, 50% $O_2$/20% $CO_2/30%\;N_2$, and 75% $O_2$/20% $CO_2/5%\;N_2$-conditions. The reduction of $O_2$ and the induction of $CO_2$ were shown in the 25-75% $O_2$-groups during storage and total change rates of $O_2$ and $CO_2$ were followed in order: 25%>50%>75%. Catalase activity was not significantly different among all groups. During storage, glutathione peroxidase activity decreased by increasing the $O_2$ concentration and was followed at 8 d in order: 0%>25%>50%>75% (p<0.05). From 2 d of storage, TBARS content had significant (p<0.05) differences in order: 0%>25%>50%>75%. The CIE $L^*$ value was higher (p<0.05) in the 25-75% $O_2$-groups, compared with the 0% $O_2$-group. During the first time, the CIE $a^*$ value was higher (p<0.05) in order: 0%<25%<50%<75% but was lower (p<0.05) in the 25-75% $O_2$-groups from 2 d of storage than in the 0% $O_2$-group. The CIE $b^*$ value was higher (p<0.05) in the 25-75% $O_2$-groups than in the 0% $O_2$-group and had significant (p<0.05) differences at 0 and 8 d in order: 0%<25%<50%<75%. Aroma patterns with the electronic nose were clearly discriminated between the 0% $O_2$-groups and the 25-75% $O_2$-groups at 8 d of storage. Therefore, high oxygen reduced stabilities of antioxidant enzymes, lipid oxidation, and color in Hanwoo beef. Furthermore, antioxidant enzyme activities and lipid oxidation could affect aroma patterns.

• Journal of Oral Medicine and Pain
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• v.1 no.1
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• pp.8-13
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• 1973

The authors had studied the oral environmental changes by salivary salivary pH, amount, periodontal Index in patient with active pulmonary tuberculosis patients. Among the subjects, The experimental group was consisted of 100 patients (50 males and 50 females) of 20-29 years and 100 persons of control group (50 males and 50 females) of 20-29 years. The measurement of salivary amount was performed with wide mouthed plastic (2 Inches) bottle for avoidance of Ionization of SiO2 by using of glass bottle and salivary pH was checked by pH meter 27 radiometer Copenhagen. The results are as follows : 1. The slivary pH does not appear to be characteristic of tuberculous paticents. 2. The obtained salivary amount indicated no significant to the tuberculous patients as compared to the obtained supposedely wealthg individuals. 3. The Russel Index wasfound higher and there had found more periodontal involvement(3 times than normal) in the experimental group.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.909-912
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• 2001

This paper presents the validities of the removal time of side forms considering the relationship between rebound number of P type schmidt hammer and compressive strength. According to test results, compressive strength of 40% of W/C at 12 hours shows 16kgf/$cm^{2}$ and 50% of W/C at 15 hours, 13kgf/$cm^{2}$. Rebound number at 9 hours after casting shows 13 and 9 (W/C 40% and W/C 50%). According to the regression analysis, rebound number of P type schmidt hammer to gain 50kgf/$cm^{2}$ of is estimated 20.1. It is thought that desirable rebound number of P type schmidt hammer to gain 50kgf/$cm^{2}$ is determined 25 considering safety factor.

• Journal of the Korean Chemical Society
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• v.10 no.1
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• pp.11-14
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• 1966

The thermodynamic parameters for the solvolysis of the p-nitrobenzyl chloride which take place in the ethanol-water mixture media were determined. From the application of this data to the formula ${\delta}_M{\Delta}H^{\neq} = a'Y + b{\delta}_M{\Delta}S^{\leq}$ the following conclusion was obtained. The substrate constant a' for this reaction was not varied in the media which contain more than 50% alcohol and less than 50% alcohol. From this, it is clear that the mechanism of this reaction is the same both in the water-rich solvent and in the alcohol-rich solvent.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1729-1732
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• 2009

Bioactivity-guided fractionation led to the isolation of two new phenylpropanoids, 3-O-p-coumaroyl-1-(4-hydroxy- 3,5-dimethoxyphenyl)-1-propanone (1) and 3-O-p-coumaroyl-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-O-$\beta$-gulcopyranosylpropanol (2), together with three known compounds, N-p-coumaroylserotonin (3), N-feruloylserotonin (4) and p-coumaric acid (5) from the leaves of Sasa quelpaertensis Nakai. Their structures were elucidated by spectroscopic methods including 1D and 2D-NMR. Compared to arbutin (I$C_{50}$ 0.048 mM) as a control, compounds 3 and 4 exhibited stronger tyrosinase inhibition activities with an I$C_{50}$ values of 0.027 mM and 0.026 mM, respectively. Compounds 1 (I$C_{50}$ 0.055 mM) and 2 (I$C_{50}$ 0.053 mM) also showed strong activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.351-361
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• 2012

This study was carried out to compare the differences in dietary habits, food consumption patterns, nutrient intakes, and serum lipid levels according to kimchi consumption in college students. The anthropometric and biochemical parameters of blood samples from the subjects were investigated, as well as a kimchi frequency questionnaire, 24-hour food recall and dietary habits. The subjects were divided into two groups according to their kimchi consumption level based on the quantitative kimchi frequency questionnaire-kimchi consumption under 50 g group and kimchi consumption over 50 g group. As kimchi consumption increased, consumption of white rice (p<0.05) and noodles increased, whereas the consumption of confections decreased. The kimchi consumption over 50 g group was more likely to eat balance meals (p<0.05), and consume fruits and vegetables (p<0.05) than the other group. On the other hand, the kimchi consumption under 50 g group was more likely to consume milk than the kimchi consumption over 50 g group. The energy and sodium (p<0.05) intakes in the kimchi consumption over 50 g group were higher compared to the kimchi consumption under 50 g group. Kimchi consumption was positively correlated with HDL-cholesterol and negatively correlated with body fat, BMI, and blood glucose level. In addition, kimchi consumption was positively correlated with cereals, meats, and vegetables intakes, and negatively correlated with milk and dairy product intakes. However, there was no significant difference between the two groups.

• Food Science and Preservation
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• v.24 no.3
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• pp.387-393
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• 2017

The objective of this study was to investigate the effect of hot water extract of Welsh onion root (HEWO) on growth of lactic acid bacteria and fermentative characteristics of yogurt. The physiochemical characteristics of HEWO such as pH, soluble solid, reducing sugar, total polyphenol content and DPPH radical scavenging activity were studied. The lactic bacterial count in brain heart infusion (BHI) broth with HEWO was about 1 log cycle higher than in control for 24 h at $37^{\circ}C$. The pH of yogurt prepared with HEWO (WY100) and 50% HEWO (WY50) was gradually decreased significantly but increased the viscosity of yogurt with increasing HEWO concentration during fermentation. The viable cells of lactic acid bacteria after fermentation for 24 h were 8.03 (control), 8.77 (WY50), 8.84 (WY100) log CFU/mL, respectively. The DPPH radical scavenging activity of yogurt increased with increasing HEWO concentration. Sensory quality of yogurt prepared with HEWO was higher than that of control. The pH and lactic acid bacteria of all tested yogurts decreased during storage for 10 days at $4^{\circ}C$ but lactic bacterial count of yogurt prepared with HEWO maintained $10^8CFU/mL$ during storage. These results indicated the potential use of HEWO as a valuable resource to improve fermentation and functionality of yogurt.

• The Journal of Internal Korean Medicine
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• v.23 no.1
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• pp.123-131
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• 2002

Objective : It is well known that modern chemotherapy against cancer has side effects to a living body, especially hemopoietic and immunologial disfunctions. However, there are no effective ways to reduce them. Recently, traditional Korean herb medicine has been reported to have some biological modifying responses. Therefore, we hypothesized that additional application of herb medicine during chemotherapy is more effective to reduce its side effects. While we were studying the effects, we have observed the inhibitory effect of Soamgudamikgitang on formation of side effects derived from Cyclophosphamide, it has been used in clinical practice at Kyung Hee Medical Center. Methods : We injected 200mg/kg of Cyclophosphamide, one time, to an experimental group, consisting of ten mice. We divided them into eight groups: normal, CPX, SAKT 2mg, SAKT 10mg, SAKT 50mg, SAKT 2mg, CPX, SAKT 10mg+CPX, SAKT 50mg+CPX. We injected Soamgudamikgitang seven days, five days, three days, and one day before we injected CPX. One day, three days, and five days after CPX injection, we injected Soamgudamikgitang again and then killed all the mice. The parameters determined in this experiment were daily body weight liver and spleen weight, RBC, WBC, and platelet for hemopoietic dysfunction and AST, ALT for hepatotoxicity, BUN, creatine for renal toxcity, lymphocyte proliferation activity and lymphocyte subsets for immunological toxcity. Results : We have found that Soamgudamikgitang has inhibitory effects on the formation of Cyclophosphamide's side effects. Significant differences between the group, which contained Cyclophosphamide, and the other group, which contains Cyclophosphamide and 2, 10, 50mg of Soamgudamikgitang respectively were observed. Platelets(2mg of Soamgudamikgitang, p<0.05 ;10mg, p<0.01 ;50mg, p<0.001), liver weight(50mg, p<0.01), spleen weight(10mg, p<0.05), AST(all groups, p<0.01), ALT(2mg, p<0.01 ;10mg, p<0.05 ;50mg, p<0.01), BUN(2mg, p<0.01 ;50mg, p<0.05). Although immunological in both lymphocyte proliferation and its subsets were not observed, which shows that Soamgudamikgitang has a strong effect on T cell activities. Conclusions : From the above results, we can expect that the combined therapy of Soamgudamikgitang and Cyclophosphamide is more effective for treating cancer patients.

• Resources Recycling
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• v.7 no.3
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• pp.3-10
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• 1998

Simulated waste liquid containing 50 ppm cobalt ion was treated by adsorbing colloidal flotation using Fe(III) or Al(IlI) as flocclant and a sodium lamyl sulfate as a collector. Parameters such as pH, surfactant concentration, Fe(III) or Al(III) concentration, gas flow rate, etc., W앙e considered. The flotation with Fe(III) showed 99.8% removal efficiency of cohalt on the conditions of initial cobalt ion concentration 50 ppm, pH 9.5, gas flow rate 70 ml/min, and flotation time 30 min. When the waste solution, was treated with 35% $H_2O_2$ prior to adsorbing colloidal flotation, the optimal pH for removing cobalt shifted m to weak alkaline range and flotation could be applied in wider range of pH as compared to non-use of $H_2O_2$. Additional use of 20 ppm Al(III) after precipitation of 50 ppm Co(II) with 50 ppm Fe(III) made the optimal pH range for preferable flotation w wider. Foreign ions such as, $NO_3^-$, $SO_4^{2-}$, $Na^+$, $Ca^{2+}$ were adopted and their effects were observed. Of which sulfate ion was f found to be detrimental to removal of cob퍼t ion by flotation. Coprecipitation of Co ion with Fe(III) and Al(III) resulted in b better removal efficiency of cobalt IOn 피 the presence of sulfate ion.