• Korean Journal of Crystallography
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• v.15 no.2
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• pp.104-109
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• 2004

The mechanical synthesis of thermoelectric material $FeSi_2$ by planetary ball mill has been investigated. The homogeneous and amorphous mixture of Fe-Si has been obtained by mechanical alloying for 850 rpm-40 min. The $\beta-FeSi_2$ powder could be synthesized by 1123 K-3 hr annealing heat treatment after mechanical alloying for 850 rpm-10, 20, and 40 min. The ceramic samples doped with the maximum content up to $10\;at.\;\%$ Co have exhibited semiconduction phenomena and maximum thermoelectric powder at 440K.

• Journal of Acupuncture Research
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• v.24 no.2
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• pp.101-112
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• 2007

목적 : CCK는 현재까지 가장 많이 연구된 식후의 포만신호 전달물질로, 음식섭취를 감소하고, 캡사이신 반응성의 미주신경에 의해 위장운동과 위내의 공복감을 억제시킨다 전침의 진통효과 발현기전에 영향을 미치는 항아편양 단백물질로서, 내인성 CCK와 그 수용체(CCK-A와 CCK-B)의 역할은 기존의 연구에서 이미 보고되어 왔다. 이에 착안하여， 본 연구에서는 포만감의 측면에서 전침자극이 내인성 CCK의 발현에 어떠한 영향을 미치는가를 살펴보고자 한다. 방법 : 48시간 절식 쥐 모델을 이용하여, 전침자극 후 30분과 60분 동안, 먹이 섭취량 변화를 측정하고, 먹이섭취량에 영향을 주는 신경전달경로에서 CCK가 관여하는지를 확인하기 위해 미주신경절제술을 시행한 쥐와 비교하였다. 한편 48시간 절식 쥐 모델을 대상으로하여 침자극 후 시상하부의 CCK mRNA 발현변화를 관찰하였다. 결과 : 전침군에서 30분과 60분 뒤의 먹이 섭취가 대조군에 비해 현저히 낮게 관찰되었는데, 포만감에 관련된 침의 이와 같은 효과는 CCK 수용체에 길항작용이 있는 lorglumide와 미주신경절제술에 의해 차단됨을 알 수 있었다. 시상하부의 CCK mRNA의 발현되는 대조군에 비하여 전침군에서 증가하는 경향이 관찰되었으나, 통계학적인 유의성은 확인 할 수 없었다. 결론 : 위의 결과에서, 전침은 포만감에 영향을 미치는 내인성 CCK 메카니즘을 활성화시키는 것을 알수 있었다.

• Korean Journal of Agricultural Science
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• v.32 no.1
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• pp.71-80
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• 2005

Phytic acid chelates excellently the metallic ions and the positive ions, especially has high affinity with $Fe^{2+}$ and $Ca^{2+}$. Merits of phytic acid can be taked in easily, edibile and harmless to body, so it was investigated that phytic acid can be substituted for EDTA in this study. 1. The Intensificative effect of chelating agent and disinfective osmotic shock of Vibrio vulnificus The number of initial existent fungi measured $1.7{\times}10^6$. The percentages of the survival fungi against the osmotic shock by distillated water were calculated at 1 minute, 3 minute and 5 minute after inoculation. The percentages of the survival fungi in $Mg^{2+}$ were 92.5%, 91.8% and 79.8% at each time, the average percentage was 88%. Also the sudden extinction was observed around 1 minute after inoculation and the survival fungi were not observed from 3 through 5 minute in spite of repeated experimentation. 2. Influence of Vibrio vulnificus on the survival of the mice. The first mouse started to die in 180 minute after inoculation in case that the inoculating number was $2.3{\times}10^7cfu/ml$. All died within 4.5 hour. The average of survival time was 226 minute. The first mouse started to die in 228 minute after inoculation in case that the inoculating number was $0.8{\times}10^6cfu/ml$. All died within 5 hour. The average of survival time was 300 minute and the survival time was 1.3 times high. The tendencies of death in two cases were similar, but the fatal rate were largely dependent on inoculating number.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.473-479
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• 2019

Gryllus bimaculatus (GB) has recently been registered as a food variety in Korea. In the present study, we prepared protein hydrolysates from GB and evaluated their antioxidant capacity. Protein hydrolysates were prepared from dried GB using enzymatic hydrolysis using five different proteases, and protein hydrolysates showing high hydrolysis value (alcalase, flavourzyme, and neutrase) were separated further into fractions ${\leq}3kDa$ and then lyophilized. Based on $RC_{50}$ values of hydrolysates (${\leq}3kDa$) obtained from four different antioxidant analyses, the flavourzyme hydrolysates showed relatively high levels of antioxidant capacity among the three hydrolysates, and in particular, it showed considerably strong antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. The flavourzyme hydrolysate also significantly inhibited peroxidation of linoleic acid. These results suggest that protein hydrolysates from GB represent potential sources of natural antioxidants. Our current studies are focused on identification of active peptides from the flavourzyme hydrolysate.

• Journal of Biomedical Engineering Research
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• v.18 no.4
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• pp.421-428
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• 1997

Magnetic field sensors made from superconducting quantum interference device (SQUID) are the most sensitive low-frequency sensors available, enabling measurements of extremely weak magnetic fields from the brain. Neuromagnetic measurements allow superior spatial resolution, compared with the present electric measurements, and superior temporal resolution, compared with the fMRl and PET, providing useful informations for the functional diagnoses of the brain. We developed a 4-channel SQUID system for neuromagnetic applications. The main features of the system are its simple readout electronics and compact pickup coil structure. A magnetically shielded room has been constructed for the reduction of environmental magnetic noises. The developed SQUID system has noise level lower than the magnetic noise from the brain. Magnetic field signals of the spontaneous r-rhythm activity and auditory evoked magnetic fields have been measured.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.263-268
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• 1999

It was found that the level of alcohol concentration in both mouse and human sera can be significantly decreased up to 42% by oral administration of the mixtures of the extracts of Hovenia dulcis THUNB and Alnus japonica Steud. A single treatment of extract from Hovenia dulcis reduced the serum alcohol concentration to 32%, compared to 13% in treating the extract of Alnus japonica. Similar patterns were observed in enhancing alcohol dehydrogenase (ADH) and glutathion-S-transferase (GST) activity in the liver. The inhibition of cathepsin activity was also greatly reduced by administrating the mixture of both extracts : however, the extract of Alnus japonica did not affect the acitivity of cathepsin. It was concluded that the mixture of both extracts had synergic effect on reducing serum alcohol concentration and improving the detoxification process due to alcohol administration in the liver.

• Food Science and Preservation
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• v.20 no.4
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• pp.459-466
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• 2013

This study was carried out in order to investigate sterilization effect and to extend storage periods of the Rubus coreanus by treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). After each treatment plot was soaked with 10, 50, 100, 200 ppm in each sterilizing solution within 30 sec, each treatment was compared during the storage time at room temperature and refrigerator temperature. As results of total plate count according to temperatures and periods, the microbial sterilizing power of each treatment plot was bigger at EW and $ClO_2$ treatment plots than the TW treatment plot; however, it sharply increased on the high concentration $ClO_2$ treatment plot. Futhermore, the cold storage treatment plot had more outstanding microbial sterilizing power than the room temperature treatment plot. As a result of observing the surface of the Rubus coreanus using scanning electron microscope (SEM), no microbe was seen in EW and $ClO_2$ treatment plot. The results of measuring enzyme activity showed a more significant decrease in EW and $ClO_2$ solutions treatment plot than TW treatment plot but gradually increased with time. The contents of total polyphenol revealed similar values on each treatment. The EW and $ClO_2$ treatment of the Rubus coreanus could be considered as good methods for inhibiting microbial growth in fresh vegetables and fruit, thereby contributing to quality maintenance.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.12 s.148
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• pp.1608-1618
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• 2005

The purpose of this investigation was to investigate the degradation products of the dye component extracted from madder dyed fabrics using the GC-MS analysis and to evaluate the change of color due to degradation treatment. Four different degradation protocols were used in this study,; refrigeration at $7^{\circ}C$ (LT), room temperature (RT), oven treatment at $100^{\circ}C$ (OV), and $H_2O_2/UV(PER)$ method. Degradation times for each thermal system were 6 hour, 24 hour, 48 hour, 1 week, 2 week, 4 week. Alizarin was detected from the control and degraded samples of both alizarin dyed and madder dyed fabrics. Benzoic acid, 2, 4-di-tert-butylphenol, phthalic anhydride were detected as the degradation products for both alizarin dyed and madder dyed fabrics. The result suggest that these products can be used as the fingerprints of GC-MS analysis for the identification of madder dye in archaeological textiles. Both alizarin dyed and madder dyed samples became less red and less yellow after degradation. In the PER degradation system madder dyed sample showed the greatest color difference even after 1 week of degradation treatment. Further research is necessary for investigating the color change in the exhumed textiles, which is caused by the dual action of dye fading and the staining of organic matters in the soil.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.652-658
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• 2012

This study was carried out to identify the ACE (Angiotensin converting enzyme) inhibitory activity of casein hydrolysates for development of anti-hypertensive hydrolysates. Sodium caseinate was treated with six kinds of commercial proteases such as Flavourzyme, Protamex, Neutrase 1.5, Alcalase, Protease M, and Protease S for 8 h individually, and was then treated with the enzyme combination for 4 h at $45^{\circ}C$. The hydrolysate which had the highest ACE inhibitory effect was then hydrolysed successively with three digestive enzymes: pepsin, trypsin, and ${\alpha}$-chymotrypsin, at $37^{\circ}C$ for 4 h under conditions mimicking those of the gastrointestinal tract. UF (ultra filtration) treatment was applied to one of the secondary hydrolysates to determine ACE inhibitory activity. When sodium caseinate was hydrolysed by commercial proteases, the degree of hydrolysis (DH) showed 2.54 to 4.25% and after secondary hydrolysis, DH showed 4.30 to 5.22%. ACE inhibitory activity and $IC_{50}$ values decreased, and inhibition rates increased during hydrolysis. Protamex treatment showed the lowest $IC_{50}$ value ($516{\mu}g/mL$) and Flavourzyme hydrolysate showed the highest $IC_{50}$value ($866{\mu}g/mL$). As the first hydrolysate was treated with Flavourzyme, the ACE inhibitory activity increased. Neutrase hydrolysate had the highest activity with an $IC_{50}$ value ($282{\mu}g/mL$). When Neutrase plus Flavourzyme treatment was hydrolyzed by digestive enzymes, the $IC_{50}$ value ($597{\mu}g/mL$) was decreased statistically (p<0.05). As Neutrase plus Flavourzyme hydrolysate is treated by UF with MW cut-off 10,000, permeate showed $273{\mu}g/mL$ of $IC_{50}$ value, showed no difference, but retentate which has over MW 10,000 showed statistically different $IC_{50}$ value, $635{\mu}g/mL$ (p<0.05).

• KSBB Journal
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• v.9 no.5
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• pp.483-491
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• 1994

It is known that a key limiting factor to the use of ultrafiltration membranes is that of membrane fouling, which has been a major cause of permeate flux reduction. In this work, the effects of several factors (operating time, protein concentration, temperature and pH, etc.) influencing permeate flux during ultrafiltration of gelatin, casein and bovine serum albumin using a hollow fiber membrane(M. W. 10,000 cut off) reactor have been examined. The permeate flux of gelatin solution was maintained almost constant during the operation up to 6 hours, but those of casein and albumin solutions were decreased to 50% and 43% of initial value after an operation time of 60min. The permeate flux with increasing concentration and temperature of protein solutions increased, but the permeate flux showed a minimum value near the isoelectric point of proteins. The permeate fluxes of protein solution were enhanced by a temperature increase and pH control. Also, it is proposed that fouling can be decreased by the pretreatment of insoluble proteins with enzymes.