• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.169-178
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• 2001

Among the recent research ideas to reduce hydrocarbon emissions emitted from SI engines till light-off of catalyst since cold start are those exploiting non-thermal plasma technique and photo-catalyst that draws recent attention by virtue of its successful application to practical use to clean up the atmosphere using the feature of its relative independence on temperature. Based on the previous research results obtained with model exhaust gases using an experimental emissions reduction system that utilizes the non-thermal plasma and photo-catalyst technique, further investigation was conducted on a production N/A 1.5 liter DOHC engine during cold start to warm-up. For the effects of non-thermal plasma-photocatalyst combined reactor, 10% concentration reduction was achieved with the fuel component paraffins, and the large increase in non-fuel paraffinic components and acetylene concentrations were similar to those of base condition. However the absolute value was locally a bit higher than those of base condition since the products was made from the dissociation and decomposition of highly branched paraffins by plasma-photocatalyst reactor. Olefinic components were highly decomposed by about 75%, due to these excellent decompositions of olefins which have relatively high MIR values, and the SR value was 1.87 that is 30% reduction from that of base condition, then, the photochemical reactivity was lowered.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.568-574
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• 2020

The feasibility of the particle-in-cell (PIC) method is assessed to simulate the non-collective phenomena like non-collective Thomson scattering (TS). The non-collective TS in the laser-plasma interaction, which is related to the single-particle behavior, is simulated through a 2D relativistic PIC code (XOOPIC). For this simulation, a non-collective TS is emitted from a 50-50 DT plasma with electron density and temperature of n_e = 3.00 × 10¹³ cm^-3 and T_e = 1000 eV, typical for the edge plasma at ITER measured by ETS system, respectively. The wavelength, intensity, and FWHM of the laser applied in the ETS system are λ_i,0 = 1.064 × 10^-4 cm, I_i = 2.24 × 10¹⁷ erg=s·㎠, and 12.00 ns, respectively. The electron density and temperature predicted by the PIC simulation, obtained from the TS scattered wave, are n_e,TS = 2.91 × 10¹³ cm^-3 and T_e,TS = 1089 eV, respectively, which are in accordance with the input values of the simulated plasma. The obtained results indicate that the ambiguities rising due to the contradiction between the PIC statistical collective mechanism caused by the super-particle concept and the non-collective nature of TS are resolved. The ability and validity to use PIC method to study the non-collective regimes are verified.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.137-141
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• 2005

The critical role of folate in the remethylation pathway for methionine synthesis from homocysteine has been well documented. Hyperhomocysteinemia resulting from inadequate folate nutrition has been implicated in increased incidence of macrovascular diseases, colorectal cancer, neural tube defects, etc. Chronic exposure to ethanol impairs folate nutrition and one-carbon metabolism in the liver, which often results in fatty liver due to a defective remetylation process. This study was carried out to investigate the chronic effects of moderate levels of alcohol and dietary folate on plasma homocysteine levels, and on histopathology and biochemical functions of the liver. Rats were raised on experimental diets with three levels of folate (0, 2, 8 mg/kg diet), and 50% ethanol (1.8 ml/kg body weight) was administered intragastically by intubation tubes three times a week for 10 weeks. Plasma homocysteine concentrations were found to be significantly influenced by dietary folate intake and alcohol administration. Among all treatment groups, plasma homocysteine levels were the highest in the animals receiving a combined treatment of folate deficient diet and alcohol administration. Plasma homocysteine concentrations were negatively correlated with folate concentration in the plasma (p<0.01) and liver (p<0.05). Among alcohol treated rats, increase in plasma homocysteine values due to macrovascular and microvascular fatty changes and spotted necrosis were observed more frequently in folate-deficient animals diet than those on folate-adequate and folate supplemented diets in alcohol-treated rats. These results indicate that folate supplementation above the recommended level might be beneficial in the prevention of alcohol-related hyperhomocysteinemia and abnormal histologic changes in the liver.

• Korean Journal of Plant Resources
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• v.20 no.5
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• pp.475-480
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• 2007

Effects of Galgeun(Pueraria radix) extracts on plasma and liver lipid composition, liver function and antioxidative capacity were investigated in rat fed high oxidized fat. Plasma total cholesterol and triglyceride concentration increased in the high oxidized fat groups, however these values showed a tendency to decrease in the Galgeun extracts groups. Plasma HDL-cholesterol concentration revealed a tendency to increase in Galgeun extracts groups. The concentration of liver total cholesterol showed no significantly different in all treatment groups, however liver triglyceride concentration showed a tendency to decrease in galgeun extracts groups. Thiobarbituric acid(TBARS) concentration in plasma and liver showed a tendency to decrease in galgeun extracts groups. The galgeun extracts samples have also decreased the plasma GOT and GPT activities, whereas they have increased the liver glutathione peroxidase, superoxide dismutase and catalase activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.401-410
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• 2023

This study examined the characteristics of eel Anguilla japonica sperm using the CASA (computer-assisted sperm analysis) system and attempted to provide the composition for artificial seminal plasma by regulating of inorganic elements. Sperm samples were first divided into four groups based on motility and progressive motility: (A) 0-10%, (B) 10-40%, (C) 40-70%, and (D) 70-100%. For observing sperm velocity variations, VCL, which is curve motion velocity, showed the highest values in all groups. The directional factor, beat cross frequency, was lower in higher activity groups, showing an opposite correlation with sperm activity. The head sizes of spermatozoa in higher activity groups were significantly larger than those in lower activity groups. The Na⁺ and K⁺ ions were important in the inorganic composition of seminal plasma in this species. Furthermore, regulating the composition in artificial seminal plasma improved the formula compared to the existing element, exhibiting 120 mM Na and 30 mM K when the sperm was conserved for a long time and 120 mM NA and 40 mM K when the sperm was conserved for a short time.

• Journal of Aquaculture
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• v.16 no.1
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• pp.1-7
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• 2003

A new technique combining forced-feeding and dorsal aorta cannulation was developed to monitor concentration of nutritions in the blood circulation and their metabolites in rainbow trout. To study the effect of dorsal aorta cannulation on stress, 30 rainbow trout (523$\pm$5.4 g; Mean$\pm$SD) were divided into 6 groups of 5 individuals each. A group was anesthetized and blood samples were taken at 0, 3, 6, 12, 24 or 48 h after dorsal aorta cannulation. Hematocrit peaked at 6 h and returned to 0 values by 12 h after dorsal aorta cannulation. Plasma cortisol and glucose concentrations also peaked at 6 h and returned to 0 values by 48 h after dorsal aorta cannulation. Based on the plasma cortisol and glucose concentrations, the rainbow trout recovered from the operation of dorsal aorta cannulation within 48 h. To compare the patterns of plasma free amino acid concentrations after force-feeding in the fish with dorsal aorta cannulation, 5 dorsal aorta cannulated individuals (511$\pm$6.2 g) were kept in a cage. After 48 h starvation, they were anesthetized and blood samples were taken at 0, 4, 8, 12, 24, 36 or 48 h after forced-feeding. The concentration of all plasma free amino acids, except isoleucine, leucine, phenylalanine, and tryptophan, also peaked at 4 h and returned to 0 values by 24 h after feeding. The combined technique allows forced-feeding and repeated sampling of blood in rainbow trout with minimum stress.

• Korean Journal of Veterinary Research
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• v.37 no.2
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• pp.451-456
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• 1997

120 heads of korean native calves were examined of serum protein by using cellulose acetate electrophoresis. During 20 days since the calves were purchased, serum protein, fibrinogen values and plasma : fibrinogen ratio were examined in the calves with respiratory and diarrheal disease. The result obtained in this investigation were as follows : 1. Among the 120 heads of calves that were purchased from market, 14 heads(22%) of calves were occurred respiratory disease, and 12 heads(20%) of calves are occurred diarrhea. Occurrence of respiratory disease was 14.5(4~20) days in average and diarrhea was 9.6(2-15) days after they had been purchased. 2. Serum protein fraction were analyzed by cellulose acetate electrophoresis. ${\beta}-globulin$, A/G ratio and ${\beta}_2-globulin$ values were decreased in the calves with respiratory disease. Especially, ${\beta}_2-globulin$ were significantly decreased. In calves with diarrhea, there was no change in ${\beta}-globulin$ values. ${\beta}_2-globulin$ values were higher than that of the normal and respiratory diseased calves. 3. ${\alpha}-globulin$ values were increased in both of calves with diarrhea and respiratory disease. This tendency was due to increase ${\alpha}_2-globulin$ values. 4. The $\gamma$-globulin value of calves with diarrhea was the lowest among the 3 groups. 5. The total protein values of normal calves were $7.0{\pm}1.1g/dl$ and that of respiratory and diarrheal diseased calves were $6.9{\pm}0.9g/dl$ and $6.6{\pm}0.8g/dl$, respectively. Total protein value of calves with diarrhea was lower than that of normal and respiratory diseased calves. Globulin value of calves with diarrhea was the lowest among them. The low value of total protein in diarrheal diseased calves was due to decrease globulin values. 6. The fibrinogen values of calves with respiratory disease ($643{\pm}189mg/dl$) were significantly higher than that of normal calves($533{\pm}135mg/dl$) and calves with diarrhea($572{\pm}188mg/dl$). The plasma : fib. ratio of respiratory diseased calves was $12.0{\pm}4.9$, normal calves was $13.8{\pm}3.5$ and diarrheal diseased calves was $12.8{\pm}4.6$. The ratio of the calves with respiratory disease was significantly decreased.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.704-712
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• 2013

This study was designed to examine the effects of bitter melon (BM) on the plasma blood glucose and cholesterol levels in diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats through an injection of streptozotocin (STZ) dissolved in a citrate buffer into the tail vein at a dose of 45 mg/kg of body weight. Sprague-Dawley rats were then fed for four weeks, with the experimental groups receiving a modified diet containing 5% or 10% powder derived from BM. The experimental groups were divided into 4 groups, consisting of the normal control group, STZ-control group and diabetic fed with BM 5% & 10% treated groups. The rats' body weight, blood glucose and cholesterol values were measured along with the hematocrit (Hct) values and aminotransferase activities. Body weight losses were observed in the diabetic groups, whereas the control rats gained weight. There were significant differences in kidney weight between the control group and the diabetic groups. The Hct levels of the diabetic BM-treated group were significantly higher than the STZ-control group. Aspartate aminotransferase activity was lower in the non-diabetic group compared to the diabetic experimental groups. Further, the blood glucose was significantly decreased in the 5% & 10% BM of the diabetic group. There were no significant difference in cholesterol levels among the diabetic groups. These results indicate that the supplementation of bitter melon may have a favorable influence on reducing the blood glucose level in STZ-induced diabetic rats.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.9
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• pp.1192-1198
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• 2011

Peri-partum metabolic profile was evaluated in winter and summer calving, with 15 Murrah buffaloes in each seasonal group. In summer calvers, significantly lower values were observed for blood plasma urea nitrogen (BUN) at day 30 pre-partum (p<0.05), on calving day (p<0.05) and at all other stages (p<0.01); plasma non-esterified fatty acids (NEFA) values were significantly lower on day 30 pre-partum (p<0.01) and on day 60 post-partum (p<0.05). This was associated with significant reduction in days to first service (DFS) and service per conception (SPC) and an overall better reproductive performance in terms of service period, risk to first service on days 60, 90 and >90, and pregnancy risk to first service up to days 60 and 90. This may be attributed to better pre-partum nutritional status. Cervical and uterine involution were completed in fewer days, involutional changes took place at a faster pace and there were a lower number of abnormal involutional changes in winter compared to summer season. This may be attributed to better post-partum nutrition and less environmental stress. However, validation requires further targeted cohort investigation with a large sample size.

• Journal of Powder Materials
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• v.19 no.5
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• pp.379-384
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• 2012

This paper reports the microstructures and thermal conductivities of $ZrB_2$-SiC composite ceramics with size and amount of SiC. We fabricated sintered bodies of $ZrB_2$-x vol.% SiC (x=10, 20, 30) with submicron and nanosized SiC densified by spark plasma sintering. Microstructure retained the initial powder size of especially SiC, except the agglomeration of nanosized SiC. For sintered bodies, thermal conductivities were examined. The observed thermal conductivity values are 40~60 W/mK, which is slightly lower than the reported values. The relation between microstructural parameter and thermal conductivity was also discussed.