• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.346-358
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• 2023

Due to the acceleration of climate change or global warming, it is important to predict rice productivity in the future and investigate physiological changes in rice plants. The research aimed to explore how rice adapts to climate change by examining the response of nitrogen absorption and nitrogen use efficiency in rice under elevated levels of carbon dioxide and temperature, utilizing the SPAR system for analysis. The temperature increased by +4.7 ℃ in comparison to the period from 2001 to 2010, while the carbon dioxide concentration was held steady at 800 ppm, aligning with South Korea's late 21st-century RCP8.5 scenario. Nitrogen was applied as fertilizer at rates of 0, 9, and 18 kg 10a^-1, respectively. Under conditions of climate change, there was an 81% increase in the number of panicles compared to the present situation. However, grain weight decreased by 38% as a result of reduction in the grain filling rate. BNUE, indicative of the nitrogen use efficiency in plant biomass, exhibited a high value under climate change conditions. However, both NUEg and ANUE, associated with grain production, experienced a notable and significant decrease. In comparison to the current conditions, nitrogen uptake in leaves and stems increased by 100% and 151%, respectively. However, there was a 25% decrease in nitrogen uptake in the panicle. Likewise, the nitrogen content and NDFF (Nitrogen Derived from Fertilizer) in the sink organs, namely leaves and roots, were elevated in comparison to current levels. Therefore, it is imperative to ensure resources by mitigating the decrease in ripening rates under climate change conditions. Moreover, there seems to be a requirement for follow-up research to enhance the flow of photosynthetic products under climate change conditions.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.2
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• pp.103-110
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• 1993

This study was made to evaluate the chemical properties of 481 farmers' orchard fields in An-Seong area. And the reasonable ferilizer rates were recommended utilizing the result of soil analysis. The results are summarized as follows : 1. As the soil fertility status of collected soil samples were evaluated on the basis of temporary optimal range for each soil chemical properties, 12.7 to 49.6% of the total 481 farmers' fields were range for soil improvement. 2. The contents of chemical component have a tendancy to decrease with depth gradually from surface to subsoil. 3. According to the relationship between the contents of soil component in subsoil and those in surface soil, the fertility condition of subsoil could be estimated on the basis of analysis data of surface soil. 4. The multiple regression equation for pear yield prediction to the organic matter and exchangable calcium contents in the soil were obtained. 5. Referring the average value, distribution ratio compared to the optimum level for each soil chemical properties and standard fertilizer rate, the soil fertility status could be categorized as "High" "Medium" and "Low". For each category, the recommended amounts for NPK and organic matter application were established. 6. The recommended rates through soul fertility diagnosis were less than farmer's dosage in the range 7.1~7.7 kg/10a for N, 0.8~11.5 kg/10a for $P_2O_5$, 7.1~19.9 kg/10a for $K_2O$ and 90~116 kg/10a for lime.

• Journal of dental hygiene science
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• v.13 no.2
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• pp.213-221
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• 2013

The mouth rinsing solution currently on the market is used for oral hygiene and reduction of halitosis, and alkaline ionized water is used for drinking purposes. The aim of this germiculture and observation through a microscope is to investigate the effect they have on the oral bacteria, and the results are as follows. 1. The change in the number of cultivated bacteria before and after the use of gargle was most dramatic for Hexamedin. It showed the highest rate of decrease in bacteria by 71.29%, followed by Listerine with 62.25%, Caregargle with 42.26%, Garglin with 33.52%, saline solution with 21.62%, alkaline ionized water with 16.08% and distilled water with 7.67%. 2. After careful analysis of statistics, Hexamedin was found to result in a significant decrease in the number of bacteria after gargling (p<0.05). 3. From observing through an light microscope after gram staining, it was evident that both a number of cocci and a few of filamentous were present before the use of gargle, whereas mostly cocci was present after the use of gargle. 4. The difference in the pH of oral rinses and alkaline ionized water had no significant influence on the number of oral bacteria. In conclusion, Hexamedin and Listerine, with the rate of decrease of bacteria of co71.29% and 62.25% respectively, have proven to be highly effective when applied before dental treatment. Other oral rinses and alkaline ionized water are relatively less efficient in decreasing the number of oral bacteria. Also, the decrease of bacteria is more affected by the antibacterial component of oral rinses than by the change in pH.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.2
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• pp.282-289
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• 2000

This study was designed to examine the validity of HPR subscale in Korean Personality Inventory for Children(KPI-C) and Attention Problems subscale in Korean Child Behavior Checklist(K-CBCL) as diagnostic tool for Attention-Deficit/Hyperactivity Disorder(ADHD). Nineteen ADHD-1 type, twenty-three ADHD-H type, sixteen Neurosis, and fifteen normal children with the age from 6 to12 were selected based on DSM-IV, and their responses of the KPI-C and CBCL were analyzed. Omnibus F-test results showed that there were significant differences in the F scores of HPR and Attention Problems T scores(p<.05). But in Posthoc analysis, the HPR and AP scores in three clinical groups were significantly higher than in normal group, but there was no group difference among three clinical groups(p<.05). These results shows that HPR subscale and Attention Problems subscale may be useful tools for screening clinical groups(vs normal group) but there was a limit to the clinical validity of two subscales as diagnostic tools for the subtypes of ADHD.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.909-914
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• 1995

In order to investigate gelation properties of Gelation Properties of ${\alpha}-lactalbumin$(${\alpha}-La$), gelling times and protein solubilities of ${\alpha}-La$ gels prepared in 0.1 M Tris-HCI buffer(pH 8.0) followed by heating at $90^{\circ}C$ for 40 minutes under different ${\alpha}-La$ concentration, NaCl, $CaCl_2$, N-ethylmaleimide(NEM), and dithiothreitol(DTT) concentration were measured. Gelling times decreased with increasing concentration of ${\alpha}-La$, NaCl, $CaCl_2$, and DTT, but increased with increasing concentration of NEM. ${\alpha}-La$ solutions made from all treatments were gelled within 40 minutes with the exception of NEM at $20{\sim}50\;mM$. Solubilities decreased with increasing concentration of ${\alpha}-La$, NaCl, $CaCl_2$, and DTT, but the solubility of NEM-modified gels increased with increasing concentration of NEM. As the results, solubilities In standard buffer were $10.4{\sim}51.3%$, $9.2{\sim}35.4%$, $11.1{\sim}35.0%$, $8.0{\sim}9.5%$, and $96.8{\sim}56.2%$, respectively. Solubilities in standard buffer containing 8 M urea and 0.5% SDS were higher than those in standard buffer, and were $41.8{\sim}81.3%$, $41.9{\sim}64.1%$, $43.5{\sim}69.8%$, $29.6{\sim}38.5%$, and $77.4{\sim}98.9%$, respectively. Solubilities in the presence of DTT were almost close to 100% in all conditions. These results indicates that the gelation rate and solubility are influenced by many factors, i.e. protein concentration, kind and concentration of salts, concentration of thiol reagents. The solubility of gel decreased with increasing the gelation rate.

• Korean Journal of Environmental Biology
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• v.20 no.3
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• pp.205-215
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• 2002

Effects of artificial and solar W-B radiation on five rhodophytes (Curdiea racovitzae, Gigaytina skottsbergii, Mazzaella obovata, Myriogramme manginii, Palmaria decipiens) from Antarctica have been investigated using PAM fluorescence in laboratory and in the field. Laboratory studies showed that there were significant differences in the UV sensitivity between different species, and that the differences appeared to be correlated with the depth of collection of the specimens. It was apparent from the observations that the samples such as M. manginii and P. decipiens collected from 20-30 m depths were move sensitive to W-B radiation compared with those collected from shallower depths, The present study confirmed that an acclimation to the surrounding light regime could be an important factor to determine the UV-sensitivity of a species or individuals and that PAM measurements are rapid and non-destructive methods to evaluate UV influences. From field studies on M. manginii and P. decipiens it was observed that both plants exhibited changes in the effective quantum yield, with the minimum values nt noon followed by n recovery in the evening. Photoinhibition occurred in these species could therefore be accounted for by so- called dynamic photoinhibition. It seems likely that this protective mechanism may contribute to survival of the species in shallow water where they may encounter intense solar radiation. The presence or absence of the W- B component under solar radiation differently affected the photosynthetic recovery process, and the rate of recovery was much stoney in UV- present than in W- absent conditions. Functional role of W- B appears to delay the recovery of photosynthesis in the studied macroalgae. Differential sensitivity to UV-B recognised between M. manginii and P. decipiens seemed to correspond well with the amount of UV-absorbing substances (UVAS) contained in the respective species. Higher tolerance to solar radiation by the latter species may be due to the higher amount of UVAS. There were variations of UVAS concentrations in algal thalli depending on the season and depth of collection.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.100-105
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• 1985

To find out the optimum level of nitrogen fertilization and better distribution of application time for seed production of Festuca arundianacea S. (var. Alta), this filed experiment was performed at Livestock Experiment Station in Suweon, during 1979 to 1981. The treatments used in this study were three nitrogen fertilizing levels (120, 180 and 240kg/ha) and four different methods of nitrogen distribution (i. single application of whole amount in early Spring, ii. 50 percent each in Autumn and early Spring, iii. 50 percent each in early Spring and at begin of heading stage and iv. 50 percent in Autumn and 25 percent in early Spring and at begin of heading stage respectively). The experiment was arranged as a split-plot design with 4 replications and performed at the experimental field of the Livestock Experiment Station in Suweon, during 1979 to 1981. The results obtained are summarized as follows: 1. Date of heading stage of Festuca arundinacea was about May 21 and that of flowering stage was June 1 to 3. The optimum stage for the seed harvesting of Festuca arundinacea (var. Alta) was June 25 about 22 to 23 days after full flowering stage. Average plant height was about 127cm and the panicle length, 24cm. 2. 1000 grain weight was 2.72g and the number of panicles were 85 to 107 per square meter. 3. The mean seed wield for two years was 678.8kg/ha with the average of whole treatments and 781.9kg/ha with the best treatment (50 percent in Autumn and 25 percent in early Spring and at begin of heading stage with 240kg/ha respectively). 4. The average germination rate of harvesting seeds was 87.0 percent and it was increasing trend according to frequent application of fertilizer. 5. The average DM yield of aftermath seed harvesting was 6155kg/ha with two cut, and it was the largest DM yield from the higher nitrogen level and also from the single application in early Spring.

• Korean Journal of Poultry Science
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• v.28 no.3
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• pp.207-213
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• 2001

The objectives or this study were to examine reed value or waste onion in duck. Experimental chicks (Cherry Valley F$_1$, 1day old, 350 chicks) were randomly assigned in 8 treatment groups, each 45 chicks, and man-aged for 7 weeks (3 kg BW, 49 days old). Treatments were control, 3%, 6% of chopped onion-fed, 5%, 10% of onion extract fed, 6% of onion meal, 3%, 6% of fermented onion-fed. Feed intake was significantly (P<0.05) high in control group, but ADG was high in 3% chopped onion-fed group. Feed requirement was very efficient in all treatment groups except 6% fermented onion-fed group. Dressing rate was high in 5% onion extract-fed group, but it was not significant. Abdominal fat was the highest in control and 6% fermented onion-fed group and lowest in 6% chopped onion-fed group. Cholesterol content was lower in all treatment groups than in control group, but it was not significantly different. Stearic acid ($C_{18:0}$) content was significantly low in all treatment group (P<0.05). However, arachidonic acid ($C_{20:4}$) content was higher in treatment group than in control group. In result, onion diet was not significantly effect on palatability, feed intake, ADG in ducks. Duck meat of onion-fed contained low cho-lesterol and high unsaturated fat content.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.146-152
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• 2007

The present study was carried out to investigate the potential acute toxicity of ethanol extracts of the aleurone layer of Oryza sativa cvs. Obongbyeo, Ilpumbyeo, and Aranghyangchalbyeo by a single oral dose in ICR mice. The test article was orally administered once by gavage to male and female mice at dose levels of 0, 2.5, 5.0, and 10.0 g/kg body weight (n=10 for male and female mice for each dose). We examined numbers of deaths, general signs, weight measurement and biochemical analysis for sexes and doses of mice control and experimental groups. All mice were alive during the experimental period so can not yield death rate and $LD_{50}$. Any significant clinical symptom was not observed in all treated groups. No significant body weight changes in treatment groups in comparison with those of control groups was observed at any dose levels in experimental groups. Plasma glucose levels were valued both control and treated groups and there were no significant differences between groups. The activities of ALT and AST were not increase in all sample treated groups when compared with the control groups. The results suggest that the toxicity of Oryza sativa cvs. Obongbyeo, Ilpumbyeo, and Aranghyangchalbyeo are low and its $LD_{50}$ is over 10.0 g/kg body weight in both male and female mice.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.2
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• pp.133-140
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• 1999

This pot experiment was conducted to find out the forage productivity and quality in a grass/clover sward as affected by the application of three different fertilizers; double superphosphate(DS), fused Mg-phosphate(FP), and complex fertilizer(CF), on newly reclaimed hilly soil. This 1st part was concerned with the forage yields, yield components and botanical composition. The results obtained are summarized as follows: 1. The significant differences in the yields(relative yields, %) of whole forages and legume were laid in the following increasing order; CF(relative yield: 150.4% in whole forages and 169.7% in ladino clover) > FP(125.4% in whole forages and 121.7% in ladino clover) > DS(100.0%). The yield of orchardgrass was significantly reduced in the DS plot, compared with the yields in the FP and CF plots, whereas these showed no significant differences between the FP and CF plots. 2. In the botanicl composition, it showed that the rates of grass : legume were 48:52% in the DS and FP, and 40:60% in the CF. It was recognized that the application of complex fertilizer contributed to the increasing of the yields of whole forages, and especially legume yield and rate in the mixed sward.