• Corrosion Science and Technology
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• v.5 no.3
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• pp.85-89
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• 2006

KAERI(Korea Atomic Energy Research Institute) has developed a repassivation rate test system which can be operated at $300^{\circ}C$. It consists of an autoclave, three electrodes for an electrochemical test and a diamond scratch tip. All the electrodes are electrically insulated from the autoclave by using high temperature fittings. Reproducible repassivation curves of alloy 600 at 300 C were obtained. Repassivation rate of alloy 600 at pH 13 was slower than that of pH 10. Stress corrosion cracking test was carried as a function of the pH at a high temperature. At pH 10, alloy 600 showed a severe stress corrosion cracking(SCC), whereas it did not show a SCC at pH 7. From the viewpoint of a relationship between the current density and the charge density, a big difference was observed in the two solutions; the slope of pH 13 was steeper than that of pH 10. So the stress corrosion susceptibility at pH 13 seems to be higher than that of pH 10. The system would be a good tool to evaluate the SCC susceptibility of alloy 600 at a high temperature.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.684-692
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• 2002

Cordyceps militaris has been known as a Chinese traditional medicine for the treatment of tuberculosis, asthma, kidney disease, debility and fatigue etc. This study was attempted to investigate the therapeutic effect of C. militaris extract on the cytotoxic activity of HepG2, human hepatocellular carcinoma cells and the liver damage induced by carbon tetrachloride in SD rats. C. militaris extracts inhibited significantly the proliferation of HepG2 cells in vitro. Carbon tetrachloride(CCl₄) caused a significant an increase in liver weight, serum aspartate aminotransferase(AST) and alanine aminotransferase(ALT) activity, alkaline phosphatase(ALP), serum thiobarbituric acid reactive substances (TBARS), microsomal TBARS, and decrease in microsomal detoxification enzymes (cytochrome P-450, P-450 reductase, cytochrome b5, b5 reductase). TBARS and ALP in serum pretreated with C. militaris extracts (300mg/kg/day, 600mg/kg/day) was significantly reduced compared to control group(CCl₄). Cytochrome b5 and b5 reductase activities were significantly increased in CM300 (300 mg/kg/day) and CM600 group(600 mg/kg/day), and cytochrome P-450 reductase was significantly increased in CM300 group. Pretreatment (100, 300, and 600 mg/kg/day for 7 days) of C. militaris with CCl₄ was significantly inhibited the accumulation microsomal TBARS and the significantly increased in the cytochrome P-450 activity. These results suggested that C. militaris (300mg/kg/day for 7 days) has appreciable therapeutic effect on CCl₄ induced hepatotoxicity.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.11-16
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• 1993

Field experiment and silkworm rearing were conducted for 4years in an attempt to reduce phosphorus fertilizer in mulberry field with high levels of phosphate. Experiments consisted of four treatments; normal recommended P application(13kg P2O5/10a), half, null and no fertilizer on each of 3 mulberry fields, two fields with 300ppm and one filed begining with 450ppm of aviable P2O5 content in soil. One of 300ppm fields was used for leaf quantity and one for leaf quality test by silkworm rearing. Leaf yield in the 300ppm field decreased after the 3rd spring in the no phosphorus treatment and in the 4th fall in the half phosphorus treatment. No yield decrease occurred in 450ppm field for 4 years. Yield decrease did occur in the next rearing season after soil phosphate content in the 10~20cm zone dropped below 150ppm. Phosphorus fertilizer should be applied at this time. Though P2O5 concentration in leaves of no phosphorus treatment was 0.18% lower that that of conventional treatment, there were no difference in cocoon quality.

• Korean Journal of Cognitive Science
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• v.11 no.3_4
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• pp.83-93
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• 2000

The effect of immediate and delayed recognition memory on event-related potential (ERP) was studied using a continuous recognition memory task and event-related potential (ERP). Among 240 stimulus words 40 words were not repeated. 100 were immediately repeated and 100 were repeated after 5 intervening words. All words presented only once during the experiment were referred to as new words. Subjects responded faster and more accurately to words repeated immediately than to new words a and to those repeated after intervening words. In terms of ERP results the immediately repeated words were associated with large P300 amplitude, early P300 latency and a absence of N400. while words repeated after a delay were associated with small P300 a amplitude. late P300 latency and the presence of N400. N400 was elicited only to new w words and to those repeated after a delay. The general morphology of the waveform was s similar for three stimulus-presentation conditions until around 3l0ms after the onset of stimulus. These results indicate that immediate and delayed recognition memory could be dissociated into two distinct processes possibly being mediated by different cerebral mechanism, and the dissociation between two types of recognition memory emerges around 3l0ms poststim'ulus. The immediate and delayed recognition memory for words are considered in terms of template matching and memory searching.

• Journal of Biomedical Engineering Research
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• v.30 no.4
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• pp.306-310
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• 2009

The purpose of this study is to observe the change in gamma-band cortical activities (GBAs) due to task difficulty. Event-related potential and gamma-band activity were investigated using electroencephalograms recorded during auditory oddball tasks with two difficulty levels. For more difficult task, the amplitude of P300 decreased and the peak latency of P300 was delayed significantly compared to easier task. The induced GBA decreased considerably during the P300 latency period and the peak latency of the induced GBA was delayed for more difficult task. The results imply that the difficulty-related change in cortical information processing may be implemented as a change in the strength of local neuronal association.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1145-1155
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• 2018

The purpose of this study was to investigate the effect of dietary restriction(DG), aerobic exercise(EG), dietary restriction with aerobic exercise(DEG) on weight, improvement of obesity, blood lipid profiles and metabolic risk factors of obese female college students. Experiments was conducted 5 times a week for 8 weeks. DG spent 300kcal/day, and EG used 300kcal/day to run, DEG each consumed 150kcal/day limits. As s result, in case of body composition, weight(p<.011) and BMI(p<.008) were decreased in DG group, and weight(p<.044, p<.017), body fat(p<.047, p<.018), BMI(p<.03, p<.008), body fat%(p<.036, p<.015) and WHR(p<.049, p<.027) were decreased in EG and DEG groups. In case of blood lipid profiles's change, there are some differences on TC(p<.006), TG(p<.047) according to the time. In DG:HDL-C(p<.028), in EG:TG(p<.038), in DEG:TC(p<.014), LDL-C(p<.007) have decreased. In case of metabolic risk factor's change, there are some differences on FBG(p<.001), insulin(p<.004), HOMA-IR(p<.001), leptin(p<.000), adiponectin(p<.038), resistin(p<.010) according to time. In DG:HOMA-IR(p<.035) and leptin(p<.007), EG:FBG(p<.043) and leptin(p<.003), DEG:FBG(p<.014), insulin(p<.005), HOMA-IR(p<.005), leptin(p<.016), and resistin(p<.040) have decreased. In conclusion, combined treatment of eating restriction with aerobic exercise was the most effective way to improvement of weight, blood lipid profiles and metabolic risk factors in obese female college students rather than respectively alone treatment.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.323-328
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• 1993

Benzo(a)pyrene [B(a)P], one of the polycyclic aromatic hydrocarbons (PAHs) is known as a potent carcinogen. As lipid consumption increases recently, the toxic effect of overheated lipid foods and fats ＆ oils were reported increasingly. In this study, the contents of B(a)p, other PAHs and rancidities of soybean oil were determined, and then the proper heating temperature, time and frequency were recommended, The work was carried out using soybean oil heated at $180\pm$5^{\circ}C$$, $200\pm$5^{\circ}C$$, and $300\pm$5^{\circ}C$$,for 50 hours. Acid Value(AV) and Conjugated Diene Value of samples were determined. The contents of B(a)P and other PAHs contents of all samples were masured by HPLC/UV method. The results obtained were as follows; Each content of PAHs in the fresh soybean oil was: Pyr 1.093, B(a)A 0.986, Ch 1.147, DMBA 1.082, B(e)P 0.664, Per 1.135, B(a)P 0.146, DBA 1.053, 3-MC 0.05 rg/kg. When the soybean oil was heated at $180\pm$5^{\circ}C$$, for 10, 20, 30, and 50 hours, B(a)P conterlts in heated soybean oils were 0.391, 0.692, 0.451, and 0.372 $\mu\textrm{g}$/kg respectively. Acid value of them were 0.26, 0.26, 0.29, and 0.33, and conjugated diene value was 0.67, 0.76, 0.99, and 1.04, respectively. When the soybean oil was heated at $200\pm$5^{\circ}C$$,and $300\pm$5^{\circ}C$$,for 10, 20, 30, and 50 hours, B(a)P coiltents in soybean oil heated at $200\pm$5^{\circ}C$$,were 0.844, 0.512, 0.479 and 0.247 Ig/kg respectively, Acid value 0.22, 0.21, 0.23 and 0.51 and CDNV 0.39, 0.49, 3.27, and 3.89. B(a)P contents in soybean oil heated at $300\pm$5^{\circ}C$$,were 0.466, 0.706, 0.607 and 0.247$\mu\textrm{g}$/kg respectively, Acid value 0.47, 1.57, 3.90, and 6.42 and CDNV 0.65, 2.15, 3.00, and 3.88.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.171-178
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• 2008

In the methanol extract from safflower seeds, two kinds of antioxidant were detected by preparative HPLC [$\mu$-Bondapak $C_{18}$ column ($7.8{\times}300\;mm$)]. Two unknown compounds were defined as CA and CB which had peaks at 22.1 min and 24.5 min, respectively. Antioxidant activity was measured by their scavenging ability on the stable tree radical of 1,1-diphenly-2-picrylhydrazyl (DPPH). For bulk extraction of antioxidants, the methanol extract was fractionated with hexan, chloroform, ethyl acetate and butanol. The ethyl acetate traction showing the highest DPPH radical scavenging activity was further purified by silica gel column chromatography to CA and CB. By NMR analysis, CA and CB were identified as N-(p-Coumaroyl)serotonin and N-feruoylserotonin, respectively. The content of N-(p-Coumaroyl)serotonin and N-feruoylserotonin were analyzed by reverse phase HPLC using a $\mu$-Bondapak $C_{18}$ column ($3.9{\times}300\;mm$) with linear gradient elution from 10% acetonitrile to 50% acetonitrile for 30min on UV detector at 300 nm. The contents of N-(p-Coumaroyl)serotonin and N-feruoylserotonin were 4.11 mg/g DW and 7.29 mg/g DW, respectively, and these two DPPH radical scavengers were detected only in the hull of seeds.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.303-307
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• 2006

In this paper, we have designed the p-type metal-oxide semiconductor field-effect transistor(pMOSFET) for SiGe devices with gate lengths of $0.9{\mu}m$ and $0.1{\mu}m$using the TCAD simulators. The electrical characteristics of devices have been investigated over the temperatures of 300 and 77K. We have used the two carrier transfer models(hydrodynamic model and drift-diffusion model). We how that the drain current is higher in the hydrodynamic model than the drift-diffusion model. When the gate length is $0.9{\mu}m$, the threshold voltage shows -0.97V and -1.15V for 300K and 77K, respectively. The threshold voltage is, however, nearly same at $0.1{\mu}m$ for 300K and 77K.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.5
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• pp.413-423
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• 2021

Apoptosis is proved responsible for renal damage during ischemia/reperfusion. The regulation for renal apoptosis induced by ischemia/reperfusion injury (IRI) has still been unclearly characterized to date. In the present study, we investigated the regulation of histone acetylation on IRI-induced renal apoptosis and the molecular mechanisms in rats with the application of curcumin possessing a variety of biological activities involving inhibition of apoptosis. Sprague-Dawley rats were randomized into four experimental groups (SHAM, IRI, curcumin, SP600125). Results showed that curcumin significantly decreased renal apoptosis and caspase-3/-9 expression and enhanced renal function in IRI rats. Treatment with curcumin in IRI rats also led to the decrease in expression of p300/cyclic AMP response element-binding protein (CBP) and activity of histone acetyltransferases (HATs). Reduced histone H3 lysine 9 (H3K9) acetylation was found near the promoter region of caspase-3/-9 after curcumin treatment. In a similar way, SP600125, an inhibitor of c-Jun N-terminal kinase (JNK), also attenuated renal apoptosis and enhanced renal function in IRI rats. In addition, SP600125 suppressed the binding level of p300/CBP and H3K9 acetylation near the promoter region of caspase-3/-9, and curcumin could inhibit JNK phosphorylation like SP600125. These results indicate that curcumin could attenuate renal IRI via JNK/p300/CBP-mediated anti-apoptosis signaling.