• 한국토양비료학회지
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• 제47권3호
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• pp.199-204
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• 2014

We conducted a short-term incubation experiment in order to understand the effect of the salinity of reclaimed coastal soils on nitrogen mineralization of livestock manure compost (LMC). Two soils with the same soil texture but different EC levels were collected from the same field. These samples were treated with 0%, 1%, 2%, and 3% of LMC by weight basis and incubated at $25^{\circ}C$ to observe changes in inorganic N contents, pH, and dehydrogenase activity with respect to time. As a result, regardless of the soil EC level, as the LMC increased, the total content of the inorganic N ($NH_4{^+}+NO_3{^-}$) increased. Difference in the soil EC level did not affect N mineralization of LMC greatly. The soil EC had negligible effect on the dehydrgenase activity as with the case of inorganic nitrogen. The $NH_4{^+}$ contents remained very low throughout the experimental period starting from the first week of incubation. We believe this is due to the high pH level (pH 7.9 and pH 8.3) of the original soils leading to ammonia volatilization. On the other hand the $NO_3{^-}$ content maintained high level as the LMC treatment level increased and reached maximum at the third week. The pH of the soil during incubation period decreased as the $NO_3{^-}$ contents increased and increased slightly after three weeks. The rise of pH level is believed to be from the $NO_3{^-}$ absorption for immobilization by microbes. In conclusion, the high soil $EC_{1:5}$ level of $12dS\;m^{-1}$ conducted in this experiment did not affect the growth in terms of soil microbes involved in N mineralization of LMC.

• International Journal of Industrial Entomology and Biomaterials
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• 제17권2호
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• pp.217-221
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• 2008

Dung beetle larvae at the $3^{rd}$ instar were injected with lipopolysaccaride and inducible proteins were examined within a pI level of 3-10 and a size level by proteomics, including 1-D SDS PAGE analysis and antibacterial assay. The immune infected larvae extracts provided seven protein bands in one-dimensional electrophoresis and its antibacterial activity also checked. Hemolymph protein from immune infected larvae of the dung beetle were separated by twodimensional gel electrophoresis and compared with those from native larvae. In 2-D gel electrophoresis, we detected 63 immune infected unique and 32 up-regulated proteins, and 36 proteins that were down-regulated or not present in treated gel. Ten protein spots from unique proteins and those presented as different level of abundance in infected and native larvae were specially expressed. These differentially expressed proteins were proposed to be involved in the defense mechanism against microorganism.

• 과학교육연구지
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• 제36권2호
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• pp.216-234
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• 2012

이 연구에서는 초등학교 5학년 영재학급 학생 14명을 대상으로, 과제의 개방도와 학생들의 인지수준에 따라 TS 활동에서 나타나는 언어적 상호작용이 어떤 특징을 보이는지 알아보았다. 연구 결과, 학생들은 과제의 개방도가 낮은 안내형 TS 활동보다는 개방도가 높은 개방형 TS 활동에서 훨씬 많은 언어적 상호작용을 보였고, 상위 수준의 상호작용도 안내형 활동보다는 개방형 활동에서 많았는데, 이런 결과는 언어적 상호작용의 거의 모든 하위 범주에서 나타났다. 또한, 안내형 과제를 수행하는 과정에서는 행동참여를 지시하거나 자기만족을 나타내는 언어사용 빈도가 높은 반면에, 개방형 과제를 수행하는 과정에서는 행동참여를 권유하거나 불만을 나타내는 빈도가 높았다. 학생들의 인지 수준에 따른 언어적 상호작용의 특징을 보면, 인지수준이 높을수록 상호작용의 빈도가 높고, 다양한 유형의 언어적 상호작용이 이루어지며, 상위수준의 상호작용이 많은 것으로 나타났다. 그러나 학생들의 인지 수준과 과제의 개방도는 학생들의 언어적 상호작용에 복합적으로 영향을 주는 것으로 나타났다. 즉, 인지 수준이 높은 학생일지라도 안내형 활동에서는 상호작용의 수준이 높지 않았으며, 개방도가 높은 활동이라도 인지 수준이 낮은 학생들은 참여도가 낮고 상호작용의 수준도 높지 않았다. 이는 개방가 높은 과제가 학생들의 사고를 자극하여 상위 수준의 상호작용을 이끌어낼 수 있지만, 그 효과는 학생들의 인지 수준에 따른 한계가 있음을 의미한다. 따라서 과제 활동에서 인지 수준이 낮은 학생들의 사고를 자극하고 참여도를 높이기 위한 과제 개방도의 조절과 교수 전략의 개발이 중요한 추후 과제라 생각된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권2호
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• pp.249-254
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• 2005

The objective of this study was to investigate effects of dietary level of CLA and the duration of feeding CLAcontaining diets on reproductive performance in sows and piglet growth rate. Tallow (3% in gestation diet and 5% in lactation diet, respectively) was incorporated as a fat source in control diet, and each 50% (dietary CLA level of 0.75% in gestation diet, and 1.50% in lactation diet, respectively) or 100% (dietary CLA level of 1.50% in gestation diet, and 2.50% in lactation diet, respectively) of tallow was replaced by a commercial CLA preparation containing 50% CLA isomers. Diets containing CLA were fed either from d 15 premating to weaning or d 74 post-mating to weaning. The level of dietary CLA and feeding duration did not affect litter size. High dietary level of CLA, however, decreased piglet weights at birth (p<0.01) and tended to decrease backfat thickness of sows at weaning. Longterm feeding of CLA-containing diets decreased piglet weights at weaning (p<0.05) and backfat thickness of sows at weaning (p<0.05). CLA supplemented in sow diet was transferred to fetus and piglets during pregnancy and nursing period, respectively. CLA contents of femoral muscle of piglets were 2.08 to 2.57 mg per g of fat at birth, and 2.36 to 4.47 mg at 10 days of age in CLA groups, while CLA was not detected in the control group. In conclusion, dietary supplementation of CLA tended to lower backfat thickness of sow and piglets' weight at birth or weaning, but did not affect total litter size. Dietary CLA was transferred efficiently during prenatal and postnatal periods of time through the placenta and milk, respectively.

• 한국대기환경학회지
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• 제27권2호
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• pp.142-151
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• 2011

In this study, we have observed PM-10 and $CO_2$ concentration in the subway cabins and analyzed the factors affecting air quality using a multivariate statistical analysis. The measurements have been conducted at Seoul metropolitan subway lines. The results show that the mean concentration of the PM-10 and $CO_2$ inside subway cabins is in the range of 62.6 to 108.0 ${\mu}g/m^3$ and 907 to 2,008 ppm, respectively. $CO_2$ level in specific sections during the rush hours has exceeded air quality guidelines for public transportation, which requires designated train ventilation controls. Correlation and regression analyses of influencing factors imply that $CO_2$ level is severely influenced by the number of passengers and PM-10 level is also correlated with the number of passengers. In particular, PM-10 level in the cabins indicates a positive correlation with outdoor PM-10 level. In addition, the PM concentration has been highly affected by the number of passengers and distance between stations.

• 보건교육건강증진학회지
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• 제26권1호
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• pp.117-128
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• 2009

Objectives: The purpose of this study was to assess the effect of mothers education attainment on prevalence of dental caries among their preschool children. Methods: Data were obtained from the third 2006 Korea National Oral Health Survey. A total of 515 preschool children aged 2 to 7 years and their mothers were selected in this study. We used mother's education level as her socioeconomic position and controlled children's tooth brushing frequency, tooth brushing before bed, the frequency of eating snack, and the preventive dental visit. Whether children experienced dental caries or not and the number of decayed or filled or missing tooth surface they had were used as outcome variables. Results: The proportion of children affected with dental caries was 46.21%. The mother's education level affected children's caries significantly (p<0.05) and children whose mother attended less than high school had more possibility of having caries than children whose mother graduated from college or more (p<0.05). This effect was still significant and got larger(p<0.05), even after controlling children's dental health behavior. Conclusion: This study showed that mother's education level affected the prevalence of caries among their preschool children. In addition, this result indicated a need for more definite policy for children's dental health in lower socioeconomic class with general dental education.

• Clinical and Experimental Reproductive Medicine
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• 제41권1호
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• pp.21-28
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• 2014

Objective: To investigate the association of individual follicular fluid (FF) leptin and adiponectin levels with the quality of the corresponding oocyte and embryo. Methods: We prospectively enrolled 67 women who underwent controlled ovarian hyperstimulation with 89 FF samples. FF and the corresponding oocyte was obtained from a single dominant preovulatory follicle at the time of oocyte retrieval. Concentrations of leptin and adiponectin were measured by enzyme-linked immunosorbent assay in an individual follicle. The oocyte quality, fertilization rate, and corresponding embryo development were assessed. Results: The FF level of leptin was significantly associated with body mass index (r=0.334, p<0.01). The FF adiponectin level was significantly higher in the normal fertilization group than the abnormal fertilization group (p=0.009) in the non-obese women. A lower FF leptin level was associated with a trend toward mature oocytes, normal fertilization, and good embryo quality, although these relationships were not statistically significant. The leptin:adiponectin ratio of FF did not differ significantly according to oocyte and embryo quality. The quality of the oocyte and embryo was not associated with the FF leptin level tertile. However, the normal fertilization rate was positively associated with FF adiponectin level tertile. There was a trend towards improved oocytes and normal fertilization rates with the lowest tertile of the FF leptin:adiponectin ratio, but this difference was not statistically significant. Conclusion: Our results suggest that a high FF adiponectin concentration could be a predictor of normal fertilization. However, the FF leptin concentration and leptin:adiponectin ratio is not significantly related to oocyte maturity and corresponding embryo development.

• 한국농공학회논문집
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• 제62권6호
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• pp.1-9
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• 2020

Reservoir storage and water level information is essential for accurate drought monitoring and prediction. In particular, the agricultural drought has increased the risk of agricultural water shortages due to regional bias in reservoirs and water supply facilities, which are major water supply facilities for agricultural water. Therefore, it is important to evaluate the available water capacity of the reservoir, and it is necessary to determine the water surface area and water capacity. Remote sensing provides images of temporal water storage and level variations, and a combination of both measurement techniques can indicate a change in water volume. In areas of ungauged water volume, satellite remote sensing image acts as a powerful tool to measure changes in surface water level. The purpose of this study is to estimate of reservoir storage and level variations using satellite remote sensing image combined with hydrological statistical data and the Normalized Difference Water Index (NDWI). Water surface areas were estimated using the Sentinel-2 satellite images in Seosan, Chungcheongnam-do from 2016 to 2018. The remote sensing-based reservoir storage estimation algorithm from this study is general and transferable to applications for lakes and reservoirs. The data set can be used for improving the representation of water resources management for incorporating lakes into weather forecasting models and climate models, and hydrologic processes.

• 농업과학연구
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• 제48권2호
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• pp.231-239
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• 2021

This study evaluated the effect of microwave-dried black soldier fly (Hermetia illucens) larvae meal (HILM) as a dietary protein source for broiler diets. A total of 250 male broilers were randomly allocated to five dietary treatment groups (10 replicates and 5 birds·pen^-1) which were respectively fed the following: a control diet (HI0) and four experimental diets in which soybean meal was replaced with 2 (HI2), 4, 6, and 8% HILM. At the end of the study (35 d), blood samples were collected from 10 randomly selected broilers (1 bird per pen) to determine serum parameters. Then, the broilers were slaughtered to determine volatile fatty acid (VFA) profiles in cecal digesta. The average daily gain and average daily feed intake linearly decreased (p < 0.01), and the feed conversion ratio linearly increased (p < 0.05) according to the inclusion level of HILM; however, there were no significant differences between the HI0 and HI2 groups. Dietary HILM increased (p < 0.01) the total VFAs in cecal digesta and decreased (p < 0.05) the triglyceride level in the blood. The broilers fed HILM had lower (p < 0.01) serum phosphorus levels; dietary HILM increased (p < 0.05) the serum calcium level. The total VFAs in cecal digesta were positively influenced by the dietary microwave-dried HILM. However, a low inclusion level (2%) of HILM in broiler diets is proper in terms of growth performance and health.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.49-49
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• 2022

One of the major problems with sweetpotato (Ipomoea batats Lam.) is the tough thread tissue that occurs in the storage root, which has a negative impact on the sales of sweet potato because it impairs the texture during cooking and the processing quality. The fiber contents in storage roots of sweetpotato is affected by cultivation conditions and environment. To investigate the effect of fiber generation at different levels of irrigation, the sweetpoatoto "Hogammi" was transplanted in greenhouse. Sweetpotato was grown in styrofoam beds(W1605*D330*H300mm) to block moisture flowing from the outside. The irrigation was carried out as 3 levels (5,10, and 20 mm through drip irrigation facilities) at 20-day intervals. Five plants were harvested per plot at 90, 100 and 120 days after transplanting (DAT). The size of the storage root was large in the order of irrigation conditions 10mm>20mm>5mm treatment. And the longer cultivation period, the larger size of the storage root was observed. As a result of the analysis of the fiber content, it showed a tendency to decrease as the cultivation period increased (90days→120days). In addition, the fiber contents of sweetpotato harvested at 90, 100 and 120 DAT in the level of 5 mm irrigation plot were 351, 324 and 207 mg/100g, respectively, which were higher than those of other irrigation level plots. During all cultivation periods, the 10mm treatment group showed the lowest fiber content of 280, 228 and 127 mg/100g. At 20 mm irrigation level, the fiber content was less than that of 5mm irrigation level, but showed a tendency to increase compared to that of 10 mm irrigation level. These results suggested that drought stress or excessive-irrigation increases the fiber content of sweetpotato, which reduces their commercial value.