• Food Science of Animal Resources
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• v.42 no.4
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• pp.712-722
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• 2022

In this study, we investigated the residual properties of tebuconazole-treated pigs. Twenty pigs were treated with different concentrations (0.25, 1.25, 2.5, 12.5, and 25 mg/kg bw/d) of tebuconazole for 28 d. Blood biochemistry, histology, and residual levels were analyzed using the VetTest analyzer, Masson's trichrome staining kit, and liquid chromatography-mass spectrometry, respectively. The final body weights were not significantly different between the control and treatment groups. Alkaline phosphatase, blood urea nitrogen, cholesterol, and gamma-glutamyl transpeptidase levels were significantly different from those of the control after exposure for 14 d. However, alanine aminotransferase levels showed changes only after exposure to pesticides for 28 d. The biochemical parameters were separated during the experimental period (14 d versus 28 d) by principal component analysis. Based on variable importance plots, blood urea nitrogen/creatinine ratio, blood urea nitrogen, glucose, and gamma-glutamyl transpeptidase are candidate biomarkers for tebuconazole exposure. The residual levels were observed at T4 (12.5 mg/kg bw/d) and T5 (25 mg/kg bw/d) in the liver and fat tissues, respectively. Fibrosis increased in the liver, kidney, and fat tissues, depending on the tebuconazole concentration. In conclusion, the residue limits of tebuconazole and the physiological changes caused by dietary tebuconazole in pigs provide important information for establishing maximum residue limits of pork and pork products.

• Journal of the Korean Society of Safety
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• v.37 no.5
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• pp.80-88
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• 2022

The Korean nuclear industry had developed the SPACE (Safety and Performance Analysis Code for nuclear power plants) code, which adopts a two-fluid, three-field model that is comprised of gas, continuous liquid and droplet fields and has the capability to simulate three-dimensional models. According to the revised law by the Nuclear Safety and Security Commission (NSSC) in Korea, the multiple failure accidents that must be considered for the accident management plan of a nuclear power plant was determined based on the lessons learned from the Fukushima accident. Generally, to improve the reliability of the calculation results of a safety analysis code, verification is required for the separate and integral effect experiments. Therefore, the goal of this work is to verify the calculation capability of the SPACE code for multiple failure accidents. For this purpose, an experiment was conducted to simulate a Control Element Drive Mechanism (CEDM) break with a safety injection failure using the ATLAS test facility, which is operated by Korea Atomic Energy Research Institute (KAERI). This experiment focused on the comparison between the experiment results and code calculation results to verify the performance of the SPACE code. The results of the overall system transient response using the SPACE code showed similar trends with the experimental results for parameters such as the system pressure, mass flow rate, and collapsed water level in component. In conclusion, it can be concluded that the SPACE code has sufficient capability to simulate a CEDM break with a safety injection failure accident.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.404-412
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• 2015

The slurry composting and bio-filtration (SCB) liquid manure has some obvious advantages including a good source of N, P and K, local availability, effective microorganism and the ability to improve soil properties. This study was conducted to evaluate the influence on the changes of soil chemical properties and yield of red pepper by fertigation cultivation with SCB application for 2 years. Red pepper was transplanted in early May in 2013 and 2014. The treatment with three replication was composed of 4 types as control (N 1.0), SCB 0.5N, SCB 1.0N, and SCB 2.0N standards of recommended nitrogen fertilizer ($19kg\;N\;10a^{-1}$). The fertigation cultivation which was installed the surface drip irrigation system was splitted 10 times as $2.5Mg\;10a^{-1}$ nutritional solution included with chemical fertilizer and SCB every 10 days during the cultivation. The height and width of pepper plant were 7.0% and 5.8% higher in SCB 2.0N treatment than that in control. The yield of red pepper increased with the increasing of SCB application rates from SCB 0.5N to 2.0N. The yield of SCB 1.0N was much better 10% in average than that of control, and there was significant differences among all treatments. pH of control soil after final harvest decreased to 6.1, however pH of SCB treated soils increased from 6.7 to 7.1 depending on SCB application rates. The Exch.-K contents of SCB treated soils were increased 13.7 to 56.9% after final harvest compared with control by $0.51cmol_c\;kg^{-1}$. Accordingly, these results showed that SCB 1.0N application rate as a recommended nitrogen level based on soil testing can be used as an alternative nitrogen management as well as plant nutrition for red pepper cultivation.

• Journal of Food Hygiene and Safety
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• v.18 no.2
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• pp.87-93
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• 2003

This study was performed to investigate aflatoxin reduction resulting from the pre-treatment and the cooking and processing of corn. Aflatoxin was produced by Aspergillus parasiticus ATCC 15517 on a type of corn imported from the United States. The aflatoxin-produced com (AC) was pre-treated in three ways in order to reduce aflatoxin: exposure to sun light for 7 days (SC); ultraviolet irradiation for 56 hours (UC); and washing with water three times (WC). Four kinds of cooking and processing methods (boiling, steaming, baking, and popping) were used to reduce aflatoxin in the AC control, SC, UC, and WC. These treatments produced com gruel, com cakes, com bread and popcorn. The aflatoxin content in the samples was determined by high performance liquid chromatography. The total aflatoxin level of the AC was significantly decreased by sun light and UV (p<0.05), and decreased by washing. After cooking and processing the AC, SC, UC, and WC, and averaging the total aflatoxin levels in the final products, the greatest reduction was found in the com gruel, then the popcorn, then the corn cakes, and the least reduction in the com bread. These results indicate that sunlight and ultraviolet energy could be effective factors in aflatokin degradation in corn before cooking and processing. This study also indicates that boiling, steaming, baking and popping were helpful in reducing the aflatoxin level in the com and that the most helpful factors were exposure time to heat. More research is needed to reduce the aflatoxin level down to below the maximum tolerable level of aflatoxin in foods.

• Clinical and Experimental Pediatrics
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• v.58 no.3
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• pp.96-101
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• 2015

Purpose: Atopic dermatitis (AD) is a chronic inflammatory relapsing skin disorder. Vitamin D plays a pivotal role in the development of AD, and interleukin (IL) 31 is known to be related to pruritus in AD. The aim of our study was to determine whether 25-hydroxyvitamin D (25(OH)D) levels are related to IL-31 levels or to the severity of AD. Methods: We enrolled 91 children with AD and 32 control subjects without history or symptoms of allergic diseases. Blood was drawn to evaluate complete blood cell count, total eosinophil count (TEC), and total IgE, specific IgE to common allergens, 25(OH)D, and IL-31 levels. Serum 25(OH)D and IL-31 levels were measured using high-performance liquid chromatography and enzyme-linked immunosorbent assay, respectively. The scoring atopic dermatitis (SCORAD) index was used to evaluate the severity of AD. Results: The mean 25(OH)D level was significantly lower in the AD group than in the control group; 25(OH)D decreased greatly in the moderate and severe AD groups compared with the mild AD group. Children with atopic sensitization showed significantly lower 25(OH)D levels than nonatopic children. However, serum IL-31 levels were not related to AD group, SCORAD index, or 25(OH)D levels. The SCORAD index was inversely correlated with serum 25(OH)D level and positively correlated with TECs and total IgE levels. Children with moderate and severe AD had significantly higher TECs than children with mild AD. Conclusion: Vitamin D is related to the severity of AD independently of IL-31.

• Korean Journal of Community Nutrition
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• v.10 no.4
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• pp.525-535
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• 2005

This study was conducted to investigate the effect of a 3 week low calorie diet (LCD) and a 9 week of behavior modification (BM) program on the weight loss, mineral and vitamin status in 22 obese women. The subject were healthy, obese (PIBW> $120\%$) women aged 20 - 50 Yr and not taking any medications known to influence body composition, mineral or vitamin metabolism During the LCD program, subjects were provided commercial liquid formulas with 125 kcal per pack and were instructed to have a formula for replacement of one meal and at least one regular meal per day within the range of daily 800 - 1200 kcal intake. During the BM program the subjects weekly attended the group nutrition counseling session to encourage themselves to modify their eating behavior and spontaneously restrict their energy intakes. The BM program focused on stimulus control, control of portion sizes and modification of binge eating and other adverse habits. The initial mean energy intake of subjects was 2016.9 $\pm$ 129.8 kcal ($100.8\%$ of RDA) and dropped to 1276.5 $\pm$ 435.7 kcal at the end of a 3 week of LCD program and elevated to 1762 $\pm$ 329.3 kcal at the end of a 9 week of BM program. Carbohydrate, protein and fat intakes were significantly decreased at the end of the LCD but carbohydrate was the only macro nutrient that showed significant decrease (p < 0.05) at the end of the BM program compared to baseline. Calcium and iron intakes decreased significantly (p < 0.01, respectively) with no significant changes in other micronutrients at the end of the LCD. The mean weight of the subjects decreased from 73.8 $\pm$ 8.0 kg to 69.2 $\pm$ 7.7 kg with LCD and ended up with 67.7 $\pm$ 7.1 kg after 9 weeks of BM. The 3 weeks of LCD reduced most of the anthropometric indices such as BMI, PIBW, fat weight, wast-to-hip ratio and subscapular and suprailiac skinfold thickness. The 9 weeks of behavior modification showed slight change or maintenance of each anthropometric measurements. Weight loss and decreased WHR with the diet program induced significantly decreased systolic blood pressure. SGOT, SGPT and serum insulin levels with improved serum lipid profiles. Biochemical parameters related to iron status such as hemoglobin, hematocrit were significantly decreased (p < 0.01) at the end of the LCD. But their mean values were within normal range. The mean serum 25 (OH) vitamin $D_3$ level significantly increased after whole diet program. Serum folate level significantly decreased after 12 weeks of diet program. In conclusion 3 weeks of LCD brought 4.6 kg reduction in body weight without risk of iron, zinc or vitamin D deficiency and 9 weeks of the BM was effective to maintain nutritional status with slightly more weight reduction (1.5 kg). However calcium intake and serum folate should be monitored during the LCD and BM because of increased risk of deficiencies.

• Journal of Embryo Transfer
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• v.33 no.3
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• pp.185-194
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• 2018

The aim of this study was performed to evaluate the effects of ice-binding protein from the arctic yeast Leucosporidium (LeIBP) supplementation on cryopreservation of boar sperm. The collected semen was diluted ($1.5{\times}10^8/ml$) in lactose egg yolk (LEY) and cooled at $5^{\circ}C$ for 3 h. The cooled semen was then diluted ($1{\times}10^8/ml$) in LeIBP containing LEY with 9% glycerol and maintained at $5^{\circ}C$ for 30 min. The semen was divided into six experimental groups (control, 0.001, 0.005, 0.01, 0.05 and 0.1 mg/ml of LeIBP). The straws were kept on above the liquid nitrogen ($LN_2$) vapors for 20 minutes and then plunged into $LN_2$. After thawing, computer-assisted sperm analysis was used for sperm motility and flow cytometry was performed to assess the viability, acrosome integrity (FITC-PSA/PI), ROS (DCF/PI), lipid peroxidation (BODIPY C11/PI) and apoptosis (Annexin V/PI), respectively. No significant responses were observed for sperm motility. However, sperm viability was significantly increased on 0.05 and 0.1 mg/ml of LeIBP groups compared to control (P < 0.05). In addition, acrosome integrity was significantly increases LeIBP groups (P < 0.05) and both ROS and lipid peroxidation level were lower in all LeIBP groups than those of control (P < 0.05). On the other hand, a significant higher apoptosis rate was observed in 0.05 and 0.1 mg/ml of LeIBP groups compared to control (P < 0.05). It can be assumed that a supplementation of LeIBP in boar sperm freezing extender is an effective method to increase the sperm qualities after cryopreservation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.2
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• pp.81-88
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• 2007

The aim of this study was to investigate whether the exposure to vinyl chloride monomer(VCM) induces lipid peroxidation in workers by evaluating the concentration of malondialdehyde(MDA) in the urine in order to assess worker's oxidative stress due to exposure of vinyl chloride monomer. The subjects investigated in the study were divided into the experimental group; 18 workers exposed to VCM, and the control group; 19 workers unexposed to VCM. A gas chromatography/pulsed flame photometric detector(GC/PFPD) was utilized to analyze thiodiglycolic acid(TDGA), which was methylated with trimethylsilyldiazomethane (2.0M in diethyl ether) in urine and the urinary MDA, the product of lipid peroxidation, was determined by high-performance liquid chromatography/ultraviolet-visible detector after derivatized with 2,4-dinitrophenylhydrazine(DNPH). The concentrations of urinary TDGA in controls and VCM exposure workers were 0.13(2.01)mg/g Cr. GM(GSD) and 0.35(1.96)mg/gCr. GM(GSD), respectively. The concentrations of urinary MDA were $0.12(2.21){\mu}mol/gCr$. GM(GSD) in controls and $1.35(1.79){\mu}mol/gCr$. GM(GSD) in VCM exposure workers. As a result of simple regressions analysis between urinary concentration of TDGA and MDA in VCM exposure workers, it was found that the $R^2$ value was 0.261 (p=0.03) and the drinking and smoking did not affect their level. In conclusion, the workers exposed to VCM have a potentially to suffered by oxidative stress due to VCM exposure and the urinary MDA can be applicable to the marker of effect to assess the level of worker's VCM exposure.

• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.419-423
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• 2008

The present study examined the effects of different calcium (Ca) sources and concentrations on the growth and Ca absorption of Agrocybe cylindracea mycelia grown in submerged cultures. The dry weights of the mycelia were not significantly different (significance level of 5%) according to the type of Ca added, and increased with increasing Ca concentration until 500 mg/L, and then decreased at concentrations of 1000 mg/L or greater. The Ca contents of groups were significantly different according to the various concentrations of the Ca source, in which the Ca content of the control group cultured without added Ca was 198.3 mg/kg, and in the treatment groups, Ca content increased to a minimum of 273.7 mg/kg (1.4 times) and a maximum of 67246.0 mg/kg (339.1 times) the Ca contents of the groups generally increased with increasing Ca concentration. According to the number of culture days, growth rates were highest during days 8 through 12, and remained relatively high until day 16. In addition, Ca contents per unit dry weight were higher in young mycelia with a shorter culture period than in mature mycelia with a longer culture period. According to pH, the most active growth and highest Ca content occurred in MCM liquid medium at pH 7.0. In conclusion, in order to produce Agrocybe cylindracea mycelia with high Ca content, it is considered most efficient to culture them in MCM liquid medium without a pH adjustment and containing 1,000 mg/L of Ca-lactate, which is commonly used as a Ca additive in food, as well as to use mycelia between 12-16 days of culturing.

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.175-188
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• 2009

In this study, we developed an experimental method of the Charles' law applicable to school. Science textbooks and literatures on this principle were analyzed to extract factors utilized in organizing the experimental setup and method. A combined structure such as with a vial and a glass tube, the former of which is for deciding the total volume and the latter of which is for easy measurement of volume, was better in measurement of volume with temperature rather than a simple structure such as syringe. Use of graduated cylinder as a water bath to control the temperature showed advantage in cooling time than using other bath of larger volume such as a beaker. A liquid drop was used as a plug in the glass tube. This plug has little resistance with the glass wall when the gas volume changes. Water as a liquid drop in the glass tube had a significant effect in volume change of gas due to evaporation, especially in the beginning of the measurement. Glycerol showing negligible effect in volume change was used. This method took about one hour and produced a good linear relationship between the temperature and volume of gas with $R^2$ = 0.999 and absolute zero temperature = $-216.7\;{^{\circ}C}$. The Charles' law experiment developed in this study can be performed with appropriate adjustment of procedure considering the purpose of the curriculum of science and chemistry subject at each school level.