• Corrosion Science and Technology
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• v.17 no.5
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• pp.211-217
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• 2018

Natural degradation of grounding-electrode in soil environment should be monitored for several decades to predict the lifetime of the grounding electrode for efficient application and management. However, long-term studies for such electrodes have many practical limitations. The conventional accelerated corrosion test is unsuitable for such studies because simulated soil corrosion process cannot represent the actual soil environment. A preliminary experiment of accelerated corrosion test was conducted using existing test standards. The accelerated corrosion test that reflects the actual soil environment has been developed to evaluate corrosion performances of grounding-electrodes in a short period. Several test conditions with different chamber temperatures and salt spray were used to imitate actual field conditions based on ASTM B162, ASTM B117, and ISO 14993 standards. Accelerated degradation specimens of copper-bonded electrodes were made by the facile method and their corrosion performances were investigated. Their corrosion rates were calculated to $0.042{\mu}m/day$, $0.316{\mu}m/day$, and $0.11{\mu}m/day$, respectively. These results indicate that accelerated deterioration of grounding materials can be determined in a short period by using cyclic test condition with salt spray temperature of $50^{\circ}C$.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.99-116
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• 2016

We herein performed animal safety assessment in accordance with Good Laboratory Practice (GLP) regulations with the aim of developing sialic acid from glycomacropeptide (hereafter referred to as "GMP") as an index ingredient and functional component in functional foods. GMP is a type of whey protein derived from milk and a safe food, with multiple functions, such as antiviral activity. A test substance was produced containing 7% (w/w) sialic acid and mostly-hydrolyzed whey protein (hereafter referred to as "7%-GNANA") by enzymatic treatment of substrate GMP. The maximum intake test dose level was selected based on 5,000 mg/kg/day dose set for male NOEL (no-observed-effect-level) and female NOAEL (no-observed-adverse-effect-level) determined by a dose-range finding (DRF) test (GLP Center of Catholic University of Daegu, Report No. 15-NREO-001) that was previously conducted with the same test substance. To evaluate the toxicity of a repeated oral dose of the test substance in connection with the previous DRF study, 1,250, 2,500, and 5,000 mg/kg of the substance were administered by a probe into the stomachs of 6-week-old SPF Sprague-Dawley male and female rats for 90 d. Each test group consisted of 10 male and 10 female rats. To determine the toxicity index, all parameters, such as observation of common signs; measurements of body weight and food consumption; ophthalmic examination; urinalysis, electrolyte, hematological, and serum biochemical examination; measurement of organ weights during autopsy; and visual and histopathological examinations were conducted according to GLP standards. After evaluating the results based on the test toxicity assessment criteria, it was determined that NOAEL of the test substance, 7%-GNANA, was 5,000 mg/kg/day, for both male and female rats. No animal death was noted in any of the test groups, including the control group, during the study period, and there was no significant difference associated with test substance, as compared with the control group, with respect to general symptoms, body weight changes, food consumption, ophthalmic examination, urinalysis, hematological and serum biochemical examination, and electrolyte and blood coagulation tests during the administration period (P<0.05). As assessed by the effects of the test substance on organ weights, food consumption, autopsy, and histopathological safety, change in kidney weight as an indicator of male NOAEL revealed up to 20% kidney weight increase in the high-dose group (5,000 mg/kg/day) compared with the change in the control group. However, it was concluded that this effect of the test substance was minor. In the case of female rats, reduction of food consumption, increase of kidney weight, and decrease of thymus weight were observed in the high-dose group. The kidney weight increased by 10.2% (left) and 8.9% (right) in the high-dose group, with a slight dose-dependency compared with that of the control group. It was observed that the thymus weight decreased by 25.3% in the high-dose group, but it was a minor test substance-associated effect. During the autopsy, botryoid tumor was detected on the ribs of one subject in the high-dose group, but we concluded that the tumor has been caused by a naturally occurring (non-test) substance. Histopathological examination revealed lesions on the kidney, liver, spleen, and other organs in the low-dose test group. Since these lesions were considered a separate phenomenon, or naturally occurring and associated with aging, it was checked whether any target organ showed clear symptoms caused by the test substance. In conclusion, different concentrations of the test substance were fed to rats and, consequently, it was verified that only a minor effect was associated with the test substance in the high-dose (5,000 mg/kg/day) group of both male and female rats, without any other significant effects associated with the test substance. Therefore, it was concluded that NOAEL of 7%-GNANA (product name: Helicobactrol) with male and female rats as test animals was 5,000 mg/kg/day, and it thus was determined that the substance is safe for the ultimate use as an ingredient of health functional foods.

• Physical Therapy Korea
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• v.5 no.1
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• pp.17-29
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• 1998

The purpose of this study was to identify the relationship between sitting and standing balance in acute stroke patients and gait outcome, and to determine appropriate test times. The subjects of this study were 20 hemiplegic patients who had been hospitalized in Sangji University Oriental Medical Hospital from August 26, 1997 through November 3, 1997. Twenty patients with cerebral infarcts had sitting and standing balance assessed on the 5th day and 10th day of stroke onset. Gait outcome was assessed 5 weeks later using the MMAS (Modified Motor Assessment Scale) score. The data were analyzed by the Spearman's Rho test and Wilcoxon signed rank test. The results were as follows: 1) Correlation coefficients between sitting balance on the 5th day and 10th day after their stroke and gait outcome 5 weeks after their stroke were $r_s$=0.89 and $r_s$=0.83, respectively. All of the sitting balance data significantly correlated with gait outcome (p<0.05). 2) Correlation coefficients between standing balance on the 5th day and 10th day after their stroke and gait outcome 5 weeks after their stroke were $r_s$=0.82 and $r_s$=0.87, respectively. All of the standing balance data significant1y correlated with gait outcome (p<0.05). 3) The difference between sitting balance scores on the 5th day and 10th day after stroke onset were statistically significant (p<0.05). But the difference between standing balance scores on the 5th day and 10th day after stroke onset were not statistically significant (p>0.05). In conclusion, sitting and standing balance tests on the 5th day and 10th day after their stroke appear to be predictive of gait outcome. Also, the result of this study can provide reference for appropriate test times as an assessment of sitting and standing balance in stroke patients.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.635-642
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• 1997

This research focused on the development of concrete overlay and test, which was conducted at 88 Highway 105k, 2 lanes of 290 m. The field application test consists of 6 cm and 10 cm bonded concrete overlay and 25 cm unbonded concrete overlay, using the slag cement for opening lanes for traffic early. The overlay were placed in a day. The whole period of traffic closing wes 8 day and it was reopened to traffic after concrete overlay has cured for 3 day. 5 cracks were founded when the field test section was investigated after 1 month, but all these may not make significant problems to overlay because these initiated and growed at the same line of repair section. The rideability and skid resistance become much better like in the new pavement after overlay. The structural capacity against deflection was much. which were verified by FWD(Falling Weight Deflectometer). The field test section is being used in a good condition and the results of field application and pavement performance analysis are encouraging. This rehabilitation methods may be adopted in Korea after a more field performance verifications.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1285-1290
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• 2003

The present study was carried out to investigate the effect of test day milk yield, test day evening milk yield, parity, stage of lactation and body weight on milk urea and milk protein concentration. A total of 319 milk samples was collected from buffaloes over four month's period and subjected to urea and protein analysis. Milk urea concentration (mg/dl) was significantly (p<0.01) increased with increasing test day milk yield. The lowest value ($57.03{\pm}1.13$) was observed in the milk yield group ${\leq}4.5kg/day$ and the highest value ($64.15{\pm}1.13$) in the group 7.7-10.7 kg/day. However, test day evening milk yield had no significant effect on milk urea concentration. Milk protein did not vary significantly with the test day milk yield as well as test day evening milk yield. A clear decreasing trend of milk urea concentration (mg/dl) was found with the increasing parity. The highest MU concentration ($64.03{\pm}1.14$) was found in the first parity and the lowest ($55.67{\pm}1.22$) was found in the sixth and above parity. Whereas, stage of lactation had no effect on milk urea concentration. Moreover, parity and stage of lactation did not have any significant effect on milk protein concentration. Body weight (kg) was also found negatively (p<0.05) related with urea content (mg/dl) in milk. The highest mean MU concentration ($64.34{\pm}0.88$) was found when body weight was between 532 and 598 kg and lower mean values ($59.24{\pm}0.94$ and $59.33{\pm}1.23$) were observed in 599 to 665 kg and ${\geq}666kg$ group. Body weight also had significant (p<0.05) effect on milk protein content. The highest milk protein content (%) was found in ${\geq}666kg$ group and the lowest in <531 kg group. In conclusion, for proper interpretation of milk urea values to monitor protein nutrition status of the buffaloes parity, milk yield and body weight should be considered.

• Journal of the Korean Home Economics Association
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• v.33 no.6
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• pp.43-59
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• 1995

the purposes of this study were to ecamine mother's perception for the quality criteria of day care center, and to estimate the differences of these according to the demographic characteristics, For these purposes, the data were collected by using questionnaire distributed to 568 mothers with children enrolled in day care center be located in Taegu. The data were analyzed by frequency, percentage, F-test, Scheffe test, regression analysis. The major findings of this research were as follows : 1. Generally, there were significant differences in the mother's perception for the quality criteria of day care center according to the demographic characteristics. 2. Among the independent variables, mother's educational level had significant influences on the all domains of mother's perception for the quality criteria of day care center.

• Journal of Animal Science and Technology
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• v.55 no.3
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• pp.173-178
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• 2013

The characteristics of lactation persistency was investigated for new evaluation trait using 4,366,900 milk yield records from 436,690 heads of Korean Holstein dairy cattle. The average lactation persistencies of first parity, second parity and over third parity were 97.5%, 95.1% and 94.6%, respectively and there was a trend that after the peak yield, lactation persistency decreased collectively. The average days of peak milk yields after calving was about 50 days, but only 33.2% of cows reached peak yields at 36~66 days (second test day). Also, there was a difference between the milk yield of cows which reached peak yields at first test day by lactation days and that of cows which reached peak yields at second to fourth test day. The estimates of heritabilty and repeatability for mean lactation persistency were 0.16 and 0.35, respectively. The genetic correlation between cumulative lactation persistency from third to tenth test day and that from third to seventh test day was 0.91 and while it increased in later test day, it decreased sharply in earlier test day. The breeding value correlations of Data II and III for Data I were 0.80 and 0.72, respectively, while the rank correlations were 0.78 and 0.71, respectively. Based on the results, the breeding value and rank correlations decreased when more data were added.

• The Journal of Korean Physical Therapy
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• v.16 no.2
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• pp.72-89
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• 2004

The purposes of this study were to test the effect of balance training and environmental enrichment on motor performance after traumatic cerebellar injury in the rat. Traumatic cerebellar injury was induced by weight drop model and after operation they were housed in individual standard cages for 24 hours. Twenty two Sprague-Dawley rats were randomly assigned into control and experimental groups. The control group was housed in standard cage for 7 days. The experimental group I was housed in standard cage after balance training for 7 days. The experimental group II was housed in environmental enrichment cage after balance training for 7 days. Vestibular drop test and tilting plane test was examined at preoperation, on 1st day after operation and 7th day after operation to the rats. The results of this experiment were as follows: 1. In motor behavioral test, at preoperation and on 1 day after operation, the outcomes were not different among the groups. But on 7th day after operation, the outcomes of group I were better than that in control group, and group II were better than group I. These results suggest that behavioral motor outcome by simultaneously application of balance training and environmental enrichment in traumatic cerebellar injured rats were more improve than that by just balance training.

• Journal of Korean Biological Nursing Science
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• v.1 no.1
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• pp.100-114
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• 1999

This study was done to investigate the effects of rapidly-rotating shift work of two-day interval on fatigue level and the concentration of urinary 17-KS, $Na^+,\;Cl^-$. The subjects were 20 nursing college students(control group) and 15 nurses in a university hospital and the study was done from Apr. 21 to May 4th, 1999. In the test group, each 5 nurses were allocated to day shift(8 AM-4 PM), evening shift(4 PM-12 MN) and night shift(12 MN-8 AM) respectively. The fatigue level were measured 30 minutes after work start on the 2nd day of work shift. Urine specimens were collected at 8 AM, 4 PM and 12 MN on the 2nd day of work shift in the control group and 30 minutes before and after work on the 2nd day of work shift in the test group. The data were analyzed with SPSS(for Window, ver 7.5). Statistical analysis was performed by using t-test, paired t-test and ANOVA. The results were as follows. 1. The perceived fatigue level in shift work 1) The physical and mental fatigue level were significantly higher in night shift than that in day or evening shift(p<0.05). In the neuro-sensory fatigue level, night shift showed higher tendency than that in day or evening shift, but there were no significant differences between each shifts. 2) Comparison between the control group and the test group: Physical fatigue level was significantly higher in night shift than that in day or evening shift of the control group(P<.001). Mental fatigue level was significantly higher in day or night shift than that in evening shift of the control group(P<.05). In the neuro-sensory fatigue level, test group showed higher tendency than that in the control group, but there were no significant differences between two groups. 3) The total fatigue level was higher in night shift than that in day shift or evening shift(P<.05). In comparing with the control group, night shift and day shift showed higher total fatigue level than that in the control group(p<0.05). 2. The concentration of urinary 17-KS, $Na^+$ and $Cl^-$ In the control group, urinary 17-KS, $Na^+$ and $Cl^-$ showed higher level in afternoon that in morning and night. In the test group, cr in day and evening shift and $Na^+$ in evening shift showed higher level at the end of work. The 17-KS concentration at the begining and the end of work in three shift groups were lower than those in control group(p<0.05), however, $Cl^-$ concentration at the begining of work in day shift, and the end of work in day and evening shift were higher than those in control group(p<0.05). $Cl^-$ concentration at the begining and end of work in night shift were considerably higher than those in control group repectively(p<0.1, p<001). $Na^+$ concentration showed a higher tendency in three shift groups except at the begining of work in night shift, but there were no statistical difference. In comparing concentration of the 17-KS, $Na^+$ and $Cl^-$ among the shift groups, 17-KS concentration showed a lower tendency and $Na^+,\;Cl^-$ showed a higher tendency in night shift: The result of this study showes that biorhythm of shift work nurse was irregular. Fatigue level as the subjective index for evaluating the health problem concerning shift work was higher in night shift and proved to be in accordance with the concentration of urinary 17-KS, $Na^+$ and $Cl^-$ used as objective indices. Disturbation of biorhythm and work stress due to night shift seems to cause the health problem of nurses and decrease of work efficiency. It is considered that work regualtion is necessary for the rational management of the nursing administration.

• Journal of the Korean Society of Food Culture
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• v.34 no.3
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• pp.353-360
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• 2019

To optimize the fermentation period of lightly salted Oiji, 3% salt was added to cucumbers that were fermented at $27{\pm}1^{\circ}C$ for 3, 4, 5, 6, or 7 days, after which their physical properties (moisture content, salinity, pH, acidity, hardness) and sensory characteristics (acceptance test, difference test) were evaluated. The moisture content was highest at day 6. Hardness slowly increased as fermentation time increased, but not significantly. The pH was highest after 3 days of fermentation, and tended to decrease as fermentation time increased, with the largest drop occurring between 4 and 5 days, and the lowest pH occurring between 6 and 7 days. Acidity was lowest after day 3 of fermentation and highest after day 7. Acidity tended to increase as fermentation period lengthened. The L-value tended to decrease as salt concentration increased. The a-value declined from day 3 to day 5, then increased significantly by day 7. The b-value was highest after 7 days, with a tendency to increase as the fermentation progressed. Acceptance test results were highest for taste and overall acceptance after 5 days of fermentation. The difference test showed that the optimal lightly salted Oiji fermentation period was approximately 5 days. These results indicate that lightly salted Oiji fermented for 5 days produced the highest acceptance.