• Journal of the Korean Society of School Health
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• v.10 no.2
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• pp.157-167
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• 1997

This study was conducted to investigate follow up tests and related factors in students who tested positive for in urine tests. For the purpose of this study, the authors analysed a self-administered questionnaire collected from 316 middle school students and 451 high school students who had positive urinalysis results in Kyungpook province during the month of February, 1996. The major findings of this study were as follows : The proportion of follow up tests among students was 39.2% in middle school students and 34.1% in high school students. There was a significant relation among a number of factors : parents' environment, health concern, and knowledge of urinalysis results, existence of nursing teachers, education concerning urinalysis, medical facility visits, and notification methods. In a multiple logistic regression analysis a higher economic level, parents' concern, knowledge of urinalysis results, medical facility visits, anti direct notification of parents were all significantly related with the follow up tests. On consideration of the above findings, in order to perform practical and effective follow-up management of students who have a positive result in urine test, direct notification of urine test result to parents as well as active health guidance in school are required.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.321-322
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• 2012

의료용 방사선 장비는 초기의 아날로그 방식의 필름 및 카세트에서 진보되어 현재는 디지털 방식의 DR (Digital Radiography)이 널리 사용되며 그에 관한 연구개발이 활발히 진행되고 있다. DR은 크게 간접방식과 직접방식의 두 분류로 나눌 수 있는데, 간접방식은 X선을 흡수하면 가시광선으로 전환하는 형광체(Scintillator)를 사용하여 X선을 가시광선으로 전환하고, 이를 Photodiode와 같은 광소자로 전기적 신호로 변환하여 방사선을 검출하는 방식을 말하며, 직접 방식은 X선을 흡수하면 전기적 신호를 발생 시키는 광도전체(Photoconductor)를 사용하여 광도전체 양단 전극에 고전압을 인가한 형태를 취하고 있는 가운데, X선이 조사되면 일차적으로 광도전체 내부에서 전자-전공쌍(Electron-hole pair)이 생성된다. 이들은 광도전체 양단의 인가되어 있는 전기장에 의해 전자는 +극으로, 전공은 -극으로 이동하여 아래에 위치한 Active matrix array을 통해 방사선을 검출하는 방식이다. 본 연구에서는 직접방식 X-ray 검출기에서 활용되는 a-Se을 ITO (Indium Thin oxide) glass 상단에 Thermal evaporation증착을 이용하여 두께 $50{\mu}m$, 33 넓이로 증착 시킨 다음, a-Se상단에 Sputtering증착을 이용하여 ITO를 11 cm, 22 cm, $2.7{\times}2.7cm$ 넓이로 증착시켜 상하부의 ITO를 Electrode로 이용하여 직접방식의 X-ray검출기 샘플을 제작하였다. 제작 과정 중 a-Se의 Thermal evaporation증착 시, 저진공 $310^{-3}_{Torr}$, 고진공 $2.210^{-5}_{Torr}$에서 보트의 가열 온도를 두 번의 스텝으로 나누어 증착 시켰다. 첫 번째 스텝 $250^{\circ}C$, 두 번째 스텝은 $260^{\circ}C$의 조건으로 증착하여 보트 내의 a-Se을 남기지 않고 전량을 소모할 수 있었으며, 스텝간의 온도차를 $10^{\circ}C$로 제어하여 균일한 박막을 형성 할 수 있었다. Sputtering증착 시, 저진공 $2.510^{-3}$, 고진공 $310^{-5}$에서 Ar, $O_2$를 사용하여 100 Sec간 플라즈마를 생성시켜 ITO를 증착하였다. 제작된 방사선 각각의 검출기 샘플 양단의 ITO에 500V의 전압을 인가하고, 진단 방사선 범위의 70 kVp, 100 mA, 0.03 sec 조건으로 X-ray를 조사시켜 ITO넓이에 따른 민감도(Sensitivity)와 암전류(Dark current)를 측정하였다. 측정결과 민감도(Sensitivity)는 X-ray샘플의 두께에 따른 $1V/{\mu}m$ 기준 시, 증착된 ITO의 넓이가 11 cm부터 22 cm, $2.7{\times}2.7cm$까지 각각 $7.610nC/cm^2$, $8.169nC/cm^2$, $6.769nC/cm^2$로 22 cm 넓이의 샘플이 가장 높은 민감도를 나타내었으나, 암전류(Dark current)는 $1.68nA/cm^2$, $3.132nA/cm^2$, $5.117nA/cm^2$로 11 cm 넓이의 샘플이 가장 낮은 값을 나타내었다. 이러한 데이터를 SNR (Signal to Noise Ratio)로 합산 하였을 시 104.359 ($1{\times}1$), 60.376($2{\times}2$), 30.621 ($2.7{\times}2.7$)로 11 cm 샘플이 신호 대 별 가장 우수한 효율을 나타냄을 알 수 있었다. 따라서 ITO박막의 면적이 클수록 민감도는 우수하나 그에 따른 암전류의 증가로 효율이 떨어짐을 검증 할 수 있었으며, 이는 ITO면적이 넓어짐에 따른 저항의 증가로 암전류에 영향을 끼침을 할 수 있었다. 본 연구를 통해 a-Se의 ITO 박막 면적에 따른 전기적 특성을 검증할 수 있었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.303-310
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• 2007

Sweetpotato shoot tops (leaves, tips and petioles) are known to be very useful parts as vegetables because of their high nutritive values and great biomass yield. In this study, the phenolic compound contents, antibacterial activity, mutagenic activity, and antimutagenic activity were investigated in sweetpotato tips that were 10-15cm of shoot top including stems, petioles and tender leaves after sprout of storage roots. The study was done by extracting sweetpotato tips with 80% ethanol and the ethanol fraction was re-extracted with hexane, chloroform, ethyl acetate, butanol and water. In ethyl acetate and butanol fractions, total phenolic compounds contained 95. 6mg/g extract and 69.3 mg/g extract, respectively, The antibacterial activity was measured using the paper disk method with concentrations of 1, 2, 5 and 10 mg/disk of butanol and ethyl acetate fractions against L. monocytogenes and S. Typhimurium strains. Higher doses of solvent extracts showed the higher antibacterial activities. In addition, 5, 10 and 20 mg/mL of the extracts were tested to determine the antibacterial activity in liquid culture. The sweetpotato leaf extract by ethyl acetate showed 1 log reduction compared to control after 24 hrs on Listeria monocytogenes, but 20 mg/ml of butanol extract completely inhibited the growth of the pathogen after 12 hrs. The extracts from ethyl acetate or butanol on Salmonella Typhimurium did less than 1 log reduction during cultivation compared to control. The numbers of S. Typhimirium TA98 and TA100 revertant colonies were 29-33 and 159-188 CFU/plate, respectively, indicating that solvent extracts were no mutagenic activity. The antimutagenic test was performed by adding direct mutagen 2-NF and MMS, and butanol and ethyl acetate showed antimutagenic effect. Thus, this study showed that sweetpotato tips had high phenolic contents and both antimicrobiol and antimutagenic properties. Sweetpotato tips would be good nutritive source because of their high nutrient content without any toxicity in consuming.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.67-80
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• 2006

The effect of environmental forcing on picophytoplankton distribution pattern was investigated in the tropical and subtropical western Pacific (TSWP) and the East Sea in September, 2002, and the continental shelf of the East China Sea (C-ECS) in August, 2003. The abundance of picophytoplankton populations, Synechococcus, Prochlorococcus and picoeukaryotes were determined by flow cytometry analyses. Picophytoplankton vertical profiles and integrated abundance $(0\sim100\;m)$ were compared with these three physiochemically different regions. Variation patterns of integrated cell abundance of Synechococcus and Prochlorococcus in these three regions showed contrasting results. Synechococcus showed average abundance of $84.5X10^{10}\;cells\;m^{-2}$, in the TSWP, $305.6X10^{10}\;cells\;m^{-2}$ in the C-ECS, and $125.4X10^{10}\;cells\; m^{-2}$ in the East Sea where increasing cell concentrations were observed in the region with abundant nutrient. On the other hand, Prochlorococcus showed average abundance of $504.5X10^{10}\;cells\;m^{-2}$ in the TSWP, $33.2x10^{10}\;cells\;m^{-2}$ in the C-ECS, and $130.2X10^{10}\;cells\;m^{-2}$ in the East Sea exhibiting a distinctive pattern of increasing cell abundance in oligotrophic warm water. Although picoeukaryotes showed a similar pattern to Synechococcus, the abundance was 1/10 of Synechococcus. Synechococcus and picoeukaryotes showed ubiquitous distribution whereas Prochlorococcus generally did not appear in the C-ECS and the East Sea with low salinity environment. The average depth profiles for Synechococcus and Prochlorococcus displayed uniform abundance in the surface mixed layer with a rapid decrease below the surface mixed layer. for Prochlorococcus, a similar rapid decreasing trend was not observed below the surface mixed layer of the TSWP, but Prochlorococcus continued to show high cell abundance even down to 100 m depth. Picoeukaryotes showed uniform abundance along $0\sim100\;m$ depth in the C-ECS, and abundance maximum layer appeared in the East Sea at $20\sim30\;m$ depth.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.206-216
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• 2018

We analyzed the effects of spatio-temporal variation in the leaf production of oaks on the density and species richness of herbivores, as well as the consumption by herbivores in the east coastal region of Korea, which is an area that has been damaged by forest fires. The main herbivore that feeds on oak leaves was moth larvae. In mid-August the insect larvae showed the highest density and species richness. Approximately 60.5% of total plant-eating insect larvae were present from August to September 2011. Oak leaf production was at its peak from July to August, and the peak damage caused by herbivores was from August to September. Depending on the investigation timing and site of the survey, oak leaf production, larval densities, and species richness showed large variations. The average production of oak leaves between July and August was estimated to be $0.96ton\;ha^{-1}$. The production of oak leaves during this period also showed spatial variations ranging from 0.34 to $1.89ton\;ha^{-1}$. In August, the consumption of oak leaves by the herbivores showed spatial variations ranging from 0.15 to $1.51ton\;ha^{-1}$. Where oak leaves had a higher yield, they tended to increase in density and species richness of the herbivores. As the production of oak leaves increased, so did the overall consumption and consumption rate by the herbivores. This means that the production of oak leaves is highly related to time and space, and there is a concentration response in which the new individuals gather. Research into the spatio-temporal heterogeneity of the food sources and their effects on the higher levels of the food web can help us quantitatively understand and evaluate the structure and functions of the burnt ecosystem that is caused by forest fires.

• Applied Microscopy
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• v.39 no.1
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• pp.27-40
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• 2009

Acute respiratory distress syndrome (ARDS), also known as an acute inflammatory lung disease is developed by various factors that is originated from the destruction of alveolar-capillary barrier, and neutrophils plays an important role in the destruction. The study intended to confirm, the anti-inflammatory effect of germanium, whether a lung injury has been mitigated with the reduction of injury in alveolar-capillary barrier resulting from inhibition of neutrophils migration in lung tissue. Test groups were divided in saline administered CON, 5 hours of endotoxin administered LPS and 5 hours of endotoxin administered Ge+LPS following 1 hours of pre-processed germanium. $100{\mu}g$ endotoxin was melted in 0.5 mL saline and sprayed into airway and 26 mg germanium per 100 g weight was administered into abdominal cavity. The endotoxin group which induced an acute lung injury with administered endotoxin showed dramatic increase of pulmonary edema (p<0.001), protein contents in bronchoalveolar lavage fluid, BALF (p<0.05) and neutrophils of infiltration in BALF (p<0.001) comparing with a control group, while a pre-treated germanium group showed significant decrease in all categories comparing to the endotoxin administerd group. In the result of a microscopic observation, the structure of alveolar-capillary barrier which is constructed with basal lamina, alveolar type I cells and endothelial cell were preserved of the pre-treated germanium group relatively well compare to the endotoxin administered group. And the construction of lamellar body, microvilli and basal lamina of alveolar type II cells were also preserved relatively well. Hence, germanium activates as an anti-Inflammatory mediator in other words, it interfered neutrophils migration into lung tissue, thereby reduced injury of alveolar-capillary barrier from toxic substances of activated neutrophils. Consequently, the study has determined that the acute lung injury induced by endotoxin has been decreased by the pre-treated germanium.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.55-62
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• 2012

This study is a survey of regulatees' perception on main contents and enforcement effect of the Act, the retailers at food stores within Green Food Zone, for the effective enforcement of "The Special Act on the Safety Management of Children's Dietary Life" legislated in 2008. Percentage, frequency analysis, and T-test are derived from the survey carried out to the 175 retailers at food stores within Green Food Zone, across the country except Jejudo, for the two months March and April of 2011. The survey results are as follows. Over 80% of the respondents are aware of comprehensive policy for child food safety and the enforcement of 'the Special Act' and considering the rate of satisfaction on food safety information provided by government, over 90% of the respondents, virtually most of them, are satisfied. The rate of awareness of Green Food Zone is about 80% and that of outstanding business for children is about 50%, showing little perception of it. The comparison of the survey result of 2011 with that of 2010, which have the same questions to the retailers within Green Food Zone, still indicates a need for enhancement of understanding on absolute standard, though it showed fairly better improvement in general. Several proposals are given in this study based on the survey results, which will contribute to the children food safety and health improvement in the end.

• Journal of Life Science
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• v.14 no.4
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• pp.670-675
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• 2004

We have examined the effects of S-nitroso-N-acetylpenicillamine (SNAP), prostaglandin $E_2$ (PG $E_2$) and dibutric cyclic AMP (dbcAMP) on the methylation of interferon- ${\gamma}$ (IFN- ${\gamma}$ ) gene in human Jurkat T cells. The CpG dinucleotide which is critical for promoter function of IFN- ${\gamma}$ gene was methylated by treatment with SNAP, PG $E_2$ and dbcAMP, respectively. The DNA methylation induced by PG $E_2$ was suppressed by the addition of 2',5'-dideoxyadenosine (DDA), an inhibitor of adenylyl cyclase, but the suppression was not observed in SNAP treated cells. The NO production was not enhanced in PG $E_2$ or dbcAMP treated cells. The methylation induced by PG $E_2$ and dbcAMP was not suppressed by the addition of $N^{G}$-methyl-L-arginine (L-NMMA), NO synthase inhibitor. In conclusion, the inhibition of INF- ${\gamma}$ gene expression by PG $E_2$ was associated with the methylation of INF- ${\gamma}$ gene by elevation of intracellular cAMP in human Jurkat T cells. However, the methylation induced by PG $E_2$ might not be mediated through the NO production.rough the NO production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.429-436
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• 2012

This study was conducted to examine the effect of feeding levels of concentrate feed on growth performance, meat quality and economic evaluation of Korean black goats. The 40 male Korean native goat were divided into four treatment groups T1 (1.5%), T2 (2.0%), T3 (2.5% feeding of concentrate feed body weight per day) and T4 (ab libitum) with ab libitum rice straw. Rice straw intake decrease as against feeding levels, however average daily gains were 22, 50, 69 and 94 g/day in T1, T2, T3 and T4 groups respectively levels (p<0.05). Dressing percentage were 41.77, 42.78, 46.12 and 49.78% in each group (p<0.05), also fat percentage were a significant increase according to feeding levels. In economic efficacy, T4 was higher than other treatment groups. In conclusion, both rice straw and concentrate feed ab libitum are good for feeding and management system on Korean black goats.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.411-420
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• 2007

This study was conducted to increase sweetpotato utilization and to determine the vegetative value of sweetpotato tips by investigating the phenolic compounds, antioxidative effect in oil, electron donating ability, nitrite scavenging effect and ACE inhibition activities. The phenolic compounds present in sweetpotato tips are the gallic, chlorogenic, gentisic, caffeic, couramic and ferulic acid, which are 16-122 times higher compared to other vegetables such as spinach, soybean sprout, and perilla leaves. In each solvent extract, the total phenolic compounds(175.8 mg/g) was composed of 55% EtOAc extraction and 39% BuOH extract, respectively. The results of induction period using the Rancimat method showed that the antioxidant activity of SP tips was higher than the tocopherol or BHT. The relative levels of each solvent extract in SP tips were as follows: EtOAc>BHT>BuOH>Tocopherol>Water>$CHCl_3$>Hexane. The peroxide value was measured every 5 days for 25 days during storage and results showed that the peroxide value, the tips, tuberous root and tocopherol were lower compared to spinach, soybean sprout and perilla leaves. Nitrite scavenging effects were excellent in sweetpotato tips, perilla leaves and soybean sprout, especially, inhibition rate of perilla leaves(72%) were superior to the others. In process of solvent extraction, activity of BuOH and water extractions were the best. ACE inhibition activity in sweetpotato tips was 1.5 times higher than in tuberous roots and $1.9{\sim}3.7$ times higher than in spinach, soybean sprout, perilla leaves.