• Journal of Korea Foundry Society
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• v.17 no.6
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• pp.560-568
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• 1997

The dissolution behavior of secondary solidification phases in squeeze cast Al-3.9wt%Cu-1.5wt%Si-1.0wt%Mg has been studied using a combination of optical microscope, image analyzer, scanning electron microscope(SEM), energy dispersive spectrometer(EDS), X-ray diffractometer(XRD) and differential thermal analyzer (DTA). Special emphasis was placed on the investigation of the effects of the nonequilibrium heat treatment on the dissolution of the second solidification phases. Ascast microstructure consisted of primary solidification product of ${\alpha}-Al$ and secondary solidification products of $Al_2Cu$, $Mg_2Si$ and $Al_2CuMg$. Equilibrium and non-equilibrium solution treatments were carried out at the temperatures of $495^{\circ}C$, $502^{\circ}C$ and $515^{\circ}C$ for 3 to 5 hours. The amount of the dissolved secondary phases increased with increasing solution treatment temperature, for example, area fractions of $Al_2Cu$, $Mg_2Si$ and $Al_2CuMg$ were approximately 0%, 1.6% and 4.2% after solution treatment at $495^{\circ}C$ for 5hours, and were approximately 0%, 0.36% and 2% after solution treatment at $515^{\circ}C$ for 5hours. The best combination of tensile properties was obtained when the as-cast alloy was solution treated at $515^{\circ}C$ for 3hours followed by aging at $180^{\circ}C$ for 10 hours. Detailed DTA and TEM study showed that the strengthening behavior during aging was due to enhanced precipitation of the platelet type fine ${\theta}'$ phase.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.167-172
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• 2007

This study was conducted to determine the effect of hygienic processing (HP) on the reduction of microorganisms during manufacturing of saengshik with two vegetables (carrots and cabbage) and two grains (barely and glutinous rice) compared to general processing (GP). For GP, distilled water was used for washing raw materials and equipment. For HP, aqueous ozone (3 ppm) in combination with 1% citric acid and 70% alcohol were used for washing raw materials and the equipment, respectively. In carrots, after cutting, total aerobic bacteria (TAB), yeast and mold (YM) and coliforms were significantly increased to 5.19, 8.04 and 2.08 ($log_{10}$ CFU/g), respectively (p<0.05). Washing effectively reduced the increased microorganisms from cross contamination during cutting, but cross contamination increased with subsequent GP drying and milling procedures to 8.56, 8.27 and 3.71 ($log_{10}$ CFU/g) for TAB, YM and coliforms, respectively (p<0.05). On the other hand, HP washing of carrots with 3 ppm ozone in combination with 1% citric acid showed higher antimicrobial effect than GP washing, significantly decreasing the number of microorganisms (p<0.05). Further cross contamination did not occur through drying and milling due to cleaning the equipments with 70% alcohol prior to processing. After milling, the number of TAB, YM and coliforms were significantly decreased to 3.89, 4.47 and not detectable level ($log_{10}$ CFU/g), respectively (p<0.05). Similar results were observed in cabbage and grains. During storage for two months at different temperatures (22 or $4^{\circ}C$), there were no changes in numbers of spoilage microorganisms in the packaged saengsik after either processing. This suggests the importance of HP for the reduction of microorganisms during saengsik production, and demonstrates the effectiveness of disinfection at each processing stage in minimizing contamination levels to enhance microbial safety of saengshik products.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.507-513
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• 2008

Purpose: Interest in the augmentation of hair growth for functional and aesthetic purpose has increased dramatically in recent years. Many hair growth products have been released, but most of these have not been proven scientifically. This study aims to measure the hair growth effect of azelaic acid and vitamin $B_6$, which have been known as hair growth materials, in animal models. Methods: Six weeks old C57BL/6 mice were used in this study and hair of mice were removed by topical treatment. The mice were divided into five experimental groups according to the testing material such as saline (negative control), propylene glycol(vehicle control), azelaic acid, vitamin B6 and azelaic acid plus vitamin B6 in combination. Hair growth was documented photographically and histologically, and then analysed by the high quality hair analysis program system. The quantity of endocrine factors, IGF-I and TGF-${\beta}1$ in the skin of mice was measured by PCR analysis. Results: The topical treatment of azelaic acid and vitamin B6 in combination for 2 weeks to dorsal skin accelerated hair regrowth more than other groups. The azelaic acid and vitamin $B_6$-combined treatment also promoted hair follicle elongation and thickness compared to the others. Histologic studies showed increased number of basal cells in azelaic acid and vitamin $B_6$-combined treatment. Furthermore, the azelaic acid and vitamin $B_6$-combined group significantly increased the expression of IGF-I but decreased the expression of TGF-${\beta}1$ in the skin of mice compared to other groups. Conclusion: These results suggest that azelaic acid and vitamin $B_6$, when used together, have an additive effect and might be used as hair growth materials.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1444-1452
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• 2007

An in vitro experiment was conducted to evaluate the differences in microbial activity of five faecal inocula from weaned pigs and one faecal inoculum from unweaned pigs in combination with 6 substrates. The substrates tested were negative control diet, corn, soybean meal, oligofructose (OF), ground chicory roots and a mixture (60% chicory pulp and 40% OF). The inocula used were derived from pigs fed either a corn-soy based diet without antibiotics (NCON), the NCON diet supplemented with oligofructose (OF), a mixture of chicory pulp (40%) and OF (60%) (MIX), ground chicory roots (CHR) or the NCON diet supplemented with antibiotics (PCON). The cumulative gas production measured fermentation kinetics and end products, such as total gas production, ammonia and volatile fatty acids, were also determined. Both the substrate and the inoculum significantly affected the fermentation characteristics. The cumulative gas production curve showed that different substrates caused more differences in traits of fermentation kinetics than the different inocula. Inocula of weaned pigs gave a significantly higher VFA production compared to the inoculum from unweaned animals, whilst the rate of fermentation and the total gas produced did not differ. OF showed the highest fermentation kinetics and the lowest $NH_3$, pH and OM loss compared to other substrates. It was concluded that the microbial activity was significantly affected by substrate and inoculum. Inoculum from weaned pigs had more potential for microbial fermentation of the carbohydrate ingredients and oligofructose than that of unweaned pigs. A combination of high and low polymer inulin may be more beneficial to the gut ecosystem than using high- or low-polymer inulin alone.

• Food Science of Animal Resources
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• v.34 no.2
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• pp.178-184
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• 2014

The application of ganghwa mugwort (GM), ascorbic acid (AC), and their combinations for reduction of residual nitrite contents was analyzed in pork sausages during storage of 28 d. Six treatments of pork sausages contained the following: Control (no antioxidant added), AC (0.05% AC), GM 0.1 (0.1% GM), GM 0.2 (0.2% GM), AC+GM 0.1 (0.05% AC + 0.1% GM) and AC+GM 0.2 (0.05% AC + 0.2% GM). Results showed that the mixture of 0.05% AC and 0.2% GM was most effective for reducing thiobarbituric acid reactive substances (TBARS) and residual nitrite contents than the control and GM added sausages alone (p<0.05). The color values of all treatments were significantly affected by adding GM (either alone or with AC). Additionally, the total color difference (${\Delta}E$) and hue angle ($H^{\circ}$) values of treatments added with GM were higher than those of the control as the amount of GM increased (p<0.05). However, there were no significant differences in the pH values between the control and all treatments during the storage period (p>0.05). Our results showed possible applications of antioxidant combination, for preventing the lipid oxidation and decreasing the residual nitrite levels of meat products.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5529-5533
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• 2014

Background: The aim of this study was to investigate the effect of a c-myc antisense oligodeoxynucleotide and 5-fluorouracil on the expression of c-myc, invasion and proliferation of HEPG-2 liver cancer cells. Materials and Methods: HEPG-2 cells were treated with lipiosome-mediated c-myc ADSON and 5-fluorouracil. The proliferation inhibition rate and invasion were measured by MTT and invasion assay, respectively. Cell apoptosis was detected by flow cytometry and expression of c-myc by RT-PCR and immunohistochemistry. Results: The proliferation inhibition rate was significantly higher in the antisense oligodeoxynucleotide added-5-fluorouracil group than single antisense oligodeoxynucleotide or 5-fluorouracil group (p<0.05). G0/G1 cells in the antisense oligodeoxynucleotide group and S cells in the 5-fluorouracil groups were significantly increased than that in the control group, respectively (P<0.01). The amplification strips of PCR products in 5-FU, ASODN and combination groups were significantly weaker than that in the control group (P<0.01). The percentage of c-myc-protein-positive cells were significantly lower in antisense oligodeoxynucleotide, 5-fluorouracil and combination groups than that in the control group (P<0.01). Conclusions: A liposome-mediated c-myc antisense oligodeoxynucleotide and 5-fluorouracil can inhibit the proliferation and invasion of liver cancer cells by reducing the expression of c-myc. A c-myc antisense oligodeoxynucleotide can increase the sensitivity of liver cancer cells to 5-fluorouracil and decrease the dosage of the agent necessary for efficacy, providing an experimental basis for the clinical therapy of liver cancer.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.405-413
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• 2010

Fig (Ficus carica L.) belongs to the mulberry tree (Moraceae) which is one of the oldest fruits in the world. It has been used as a digestion promoter and a cure for ulcerative inflammation and eruption in Korea. The present study investigated the antimicrobial activity of methanol (MeOH) extract of fig leaves against methicillin-resistant Staphylococcus aureus (MRSA) isolated in clinic. The MeOH extract (MICs, 2.5 to 20 mg/mL; MBCs, 5 to 20 mg/mL) was demonstrated as antibacterial activity in isolates MRSA 1-20. The administration of the MeOH extract in combination with oxacillin or ampicillin induced a reduction of ${\geq}$4-8-fold in all tested bacteria, which was considered to be synergistic based on a FICI of ${\leq}$0.375-0.5. Furthermore, time-kill study was found that a combination of MeOH extract with oxacillin or ampicillin produced a more rapid decrease in the concentration of bacteria CFU/mL than MeOH extract alone. The results suggest that fig leaves could be employed as a natural antibacterial agent in MRSA infection care products.

• Journal of Convergence for Information Technology
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• v.10 no.8
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• pp.179-186
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• 2020

The purpose of this study was to investigate the effects on the bio signal of brain waves and pulse waves using acupressure thermal bed combined with acupressure and thermal therapy. Forty healthy adults were divided into 20 experimental groups using combinatorial stimulation beds and 20 non-irritating controls. As a result of the experiment, the EEG was significantly increased in the delta wave and theta wave in the experimental group, and the alpha wave and beta wave decreased significantly. The pulse wave increased the parasympathetic activity index in the experimental group and the heart rate decreased. There was no difference in the control group. This change in EEG can be seen as a combination stimulation bed having a sleep-inducing effect, and a change in pulse wave can seen as having a relaxing effect. This study is expected to be used as basic data for the development of various combination stimulators and functional bed products.

• Journal of Integrative Natural Science
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• v.6 no.1
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• pp.34-38
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• 2013

Tributyltin hydride ($n-Bu_3SnH$), an endocrine disruptor, was slowly polymerized by the group 4 ${Cp^{\prime}}_2TiCl_2/N$-selectride (Cp' = $C_5H_5$, Cp; $Me-C_5H_4$, Me-Cp; $Me_5C_5$, $Cp^*$) catalyst combination to give two phases of products: one is an insoluble cross-linked solid, polystannane in 3-25% yield as minor product via disproportionation/dehydrocoupling combination process, and the other is an oil, hexabutyldistannane in 65-90% yield as major product via simple dehydrocoupling process. Disproportionation/dehydrocoupling process first produced a low-molecular-weight oligostannane possessing partial backbone Sn-H bonds which then underwent an extensive cross-linking reaction of backbone Sn-H bonds, resulting in the formation of an insoluble polystannane. The disproportionation/dehydrocoupling of a tertiary hydrostannane mediated by early transition metallocene/inorganic hydride is quite unusual and applicable.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.51-61
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• 2012

The new alkali pulping process combined with electron beam treatment was applied to utilize hemp bast tissues as a new valuable fibrous resource. Hemp bast tissues have some chemical properties with high lignin contents and holocellulose not to be defiberized by alkali pulping only, compared with the bast tissue of paper mulberry. To make up for the weakness of traditional alkali pulping process, electron beams were directly irradiated into the swelled bast tissue of hemp in NaOH solution and distilled water, and then facilitated the defiberization of hemp bast tissues. The papermaking from hemp bast fibers manufactured by the combination pulping process showed good apparent density, formation structure and air permeability, and had some mechanical properties with lower tensile, tear, burst strength and folding endurance. It is finally concluded that the combination pulping process with electron beam treatment could be suggested a new alternative for non-woody fibers.