• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.2
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• pp.127-134
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• 2011

This experiment was carried out to know the adaptability and forage production and quality of corn hybrid for silage at paddy field of Chungnam region from 2008 to 2009. Among agronomic characteristics, 'Kangdaok' and 'Kwangpyongok' hybrid were somewhat strong for waterlogging and good stay green, lodging, disease and insect resistance. The dry matter yield of 'Kangdaok' and 'Kwangpyongok' hybrid were the highest among korean corn hybrids. Among introduced hybrid, 'P32T83' hybrid was strong for lodging and insect resistance, and had lower ear height and high Brix ($B^o$, %). The dry matter yield of 'P32T83' and 'P32P75' hybrid were 20,150 kg/ha and 20,500 kg/ha, respectively. The 'P32P75' hybrid was high as 73% in vitro dry matter digestibility (IVDMD) and good stay green. The result of this study indicated that 'Kangdaok', 'Kwangpyongok', 'P32T83' and 'P32P75' hybrid could be recommended as having good characters according to production, waterlogging tolerance, stay green, disease and insect resistance at paddy field in the middle region of Korea.

• Clinical and Experimental Pediatrics
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• v.51 no.3
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• pp.323-328
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• 2008

Purpose : Asthma is defined as chronic inflammation of the lower small airways, and bronchial hyperreactivity (BHR) is a pathophysiologic feature of asthma. It has been proposed that although there is no direct variable capable of assessing the small airways, a forced expiratory flow of between 25 and 75 percent ($FEF_{25-75}$) might be considered a more sensitive early marker of small airway obstruction than the forced expiratory volume in 1 second ($FEV_1$). Thus, we proposed that the presence and degree of positive responses to bronchial methacholine testing were related to the difference (DFF) and ratio (RFF) between $FEV_1$ and $FEF_{25-75}$ in asthmatic children. Methods : The subjects were 583 symptomatic children, including 324 children with BHR and 259 controls. Pulmonary function tests, methacholine challenge tests, and skin prick tests were performed, and the total eosinophil count, total serum IgE, and serum eosinophil cationic protein level were measured in all subjects. From a concentration-response curve, the methacholine concentration required to produce a decrease of 20% from post-saline $FEV_1$ was calculated ($PC_{20}$). Results : The median DFF and RFF values decreased in controls compared to subjects with bronchial hyperresponsiveness, and this trend was found in groups ranked by its severity. $PC_{20}$ had a negative correlation with DFF and RFF. Cutoff values of 0.5 for DFF and 1.042 for RFF were identified, and sensitivity and specificity were calculated. Conclusion : This study revealed that DFF and RFF might be predictive of bronchial hyperresponsiveness in the context of normal $FEV_1$ in children.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.274-282
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• 1992

Annual forage crops have been increasingly important for conpensating insufficient forage production of perennial pastures took place for short interval. This experiment was conducted to determine the effect of sward composition and NㆍP fertilization on forage production and intercompetition of subterranean clover-Italian ryegrass and berseem clover-Italian ryegrass. The two clovers were grown in the field at the clover/ryegrass ratios of 0/100, 25/75, 50/50, 75/25 and 100/0 where no, N (200 kg /ha), P (50 kg /ha) or NㆍP fertilization was done. Each crop was separated after harvest and drying. Relative Crowding Coefficient (RCC), aggressivity and Relative Yield Total (RYT) were analyzed on the basis of the harvested dry matter of each crop. Berseem clover-ryegrass mixtures produced greater yield than subclover-ryegrass mixtures as a result of higher yields of the two component species. In the former forage yield was increased with increased rate of clover up to 75%, while in the latter the highest yields were obtained at more than 50% of the clover. In the mixtures N stimulated the growth of ryegrass, whereas P did only that of subclover. The two clovers produced more forage than the companion grass under no and only P fertilization although the reverse result was true under N or NㆍP fertilization, but the annual forage yield was decreased in the order of N and P, N, P, and no fertilization. The mixture yields were overyielded compared to the Expected Yield. Although generally RCCs and RYTs of subclover were higher than those of berseem clover in the mixtures differing the composition rate or under no and only P fertilization, those of the former clover were lower under N or NㆍP fertilization. In the clover-ryegrass mixtures, ryegrass acted as an aggressor and became more aggressive under P fertilization.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.209-209
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• 2017

The application of liquid swine manure to soil has been commonly reported to increase crop productivity by improving plant nutrient availability. This study was conducted to investigate the effect of liquid swine manure (LSM) application on yield of green manure crops in paddy. Three different application rates of LSM equivalent to 25%, 50%, and 75% of standard fertilization rate of P were applied to the paddy field after rice harvest, and two cover crops, hairy vetch (Vicia villosa Roth) and barley (Hordeum vulgare L.), were subsequently mix-seeded and cultivated. Plant height of barley was 7% higher in LSM P25% and LSM P50% compared to control treatment (no LSM application), while no significant difference was observed between LSM P75% and control. However, there were no significant differences in plant height of hairy vetch among treatments. Dry matter (DM) yield of green manure increased with LSM application rate, reaching a maximum at LSM P50% (38 and 17% yield increase over control for hairy vetch and barley, respectively), but it decreased at LSM P75% rate. Nitrogen production by green manure crops was the highest in LSM P50% treatment, where the amount of produced N was 57% higher than the optimum N fertilization level for rice ($90kg\;N\;ha^{-1}$). Excess green manure biomass above an optimum level can be removed and utilized either for incorporation into nearby cropland or for sale as fresh forage. Therefore, it is concluded that the application rate of LSM P50% is recommendable for the maximum biomass and nitrogen production from green manure crops in paddy.

• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.69-75
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• 2004

The inhibitory effect of the food processing agent on growth of Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes was performed with hydrogen peroxide and lactic acid, and combination of hydrogen peroxide and lactic acid. The minimun inhibitory concentration (MIC) of hydrogen peroxide in E coli O157:H7 was 100 ppm at pH 5.0, 6.0, 6.5 and 7.0, while in Listeria monocytogenes 25 ppm at PH 5.5, 6.0 and 50 ppm at PH 6.5, 75ppm at pH 7.0. MIC of lactic acid in E coli O157:H7 was 2500 ppm at pH 5.0, 6.0, 6.5 and 7.0. MIC of lactic acid in S. Enteritidis was 1250 ppm at pH 5.0, 2500 ppm at pH 5.5, 6.0, 5.5 and 7.0, while in L monocytogenes 625 ppm at pH 5.5 and 125 ppm at pH 6.0, 6.5 and 7.0. MIC of combined hydrogen Peroxide and lactic acid in E. coli O157:H7, S. Enteritidis, and L. monocytogenes was 75 ppm of hydrogen peroxide with 2500 ppm of lactic acid at pH 6.5. The correlations between MICs of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogene were obtained through the coefficient of $determination(R^2)$. $R^2$ value were 0.9994, 0.9935 and 0.9283, respectively. The inhibitory effect of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogenes could be confirmed from the result of this experiment. Therefore, it was expected that the food process would increase or maintain by using lactic acid together with hydrogen peroxide.

• Journal of Welding and Joining
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• v.9 no.1
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• pp.40-47
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• 1991

The most fatigue tests carried out under the either stress or strain control, but machines and structures had taken variable stress. This variable stress was treated as statistics based on p-type distributions. In this paper, the cumulative fatigue damage of SM45C round bar specimens having a center hole resulting from block loading with p-distributions in rotating bending conditions, is presented. The value of p was changed in the range from 0.25 to 1; 0.25, 0.5, 0.75, 1. The following conclusions were obtained through the constant stress amplitude experiments and the block loading experiments. (1) In constant loading test, fatigue life was affected by cyclic rate. From experimental data, N$_{f}$ (100cpm)/N$_{f}$(3000cpm)equal to 0.56. (2) In case of the cyclic rate 100cpm and 3000cpm, at the high stress amplitude level the crack propagation life N$_{*}$f is longer than the low stress amplitude level. (3) Miner's hypothesis may be valid for p=0.75 and prediction of fatigue life by Haibach's method agree with experimental data well for the case p=0.5, while the modified Miner's method agree with experimental data well for the case p=0.25.5.

• Journal of the Korean Ceramic Society
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• v.25 no.6
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• pp.631-638
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• 1988

Effect of Ca/P mole ratio on the precipitates and powder properties of hydroxyapatite was investigated. Powder and precipitates of hydroxyapatite were synthesized by the reaction of Ca(NO3)2.4H2O and (NH4)2 HPO4 solutions at room temperature. The pH value and compositions (Ca/P mole ratio) in starting solutions were 11 and 1.64-1.79(or 1.85), respectively. Rodlike hydroxyapatite precipitates were agglomerated together. The average agglomerated particle size was ranged from 2-8${\mu}{\textrm}{m}$. Among compositions, the minimum agglomerated particle size was shown at the Ca/P mole ratio 1.75. CO2 was contained in hydroxyapatite powders and these ultrafine powders had poor crystallinity. The specific surface area and specific total pore volume of hydroxyapatite powders were 104-137$m^2$/g and 0.396-0.467cc/g, respectively. When the Ca/P mole ratio was 1.75, these values were the maximum. And water content increased with the Ca/P mole ratio(Ca/P mole ratio>1.67). In most cases, hydroxyapaite was stable to 130$0^{\circ}C$. However, in the case of Ca/P mole ratio 1.64, hydroxyapatite was changed to $\alpha$-whitlockite at 120$0^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.409-415
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• 2001

Physiological activities of unripened fruit, ripened fruit and leaf of Rubus coreanus Miquel were examined. Total polyphenolic compound content, electron donating ability (EDA), nitrite scavenging activity and SOD-like activity were examined using extracts of Rubus coreanus Miquel extracted with various extraction solvents such as 80% methanol, 75% acetone and water. The leaf part of Rubus coreanus Miquel included higher contents of total polyphenol compound compared with those of the other sample groups, unripened and ripened fruit. The total polyphenol compound content of leaf (100 g, dry base) extracted with 75% acetone showed the highest value of $5.06{\sim}5.87g$. As for EDA, unripened fruit showed over 90% of electron donating ability. No significant difference in EDA was found among the extracts prepared with various extraction solvents, 80% methanol, 75% acetone and water. Rubus coreanus Miquel extracts showed different nitrite scavenging abilities under different pH conditions. The nitrite scavenging abilities at pH 1.2 were in the range of $41.25{\sim}63.24%$ whereas they were $1.59{\sim}10.99%$ at pH 4.2 and $-2.84{\sim}7.94%$ at pH 6.0. The high levels of SOD-like activities were found in ripened fruit when different extracting methods were applied. Agar diffusion tests were accomplished to examine the antimicrobial activities of the extracts prepared from unripened fruit, ripened fruit and leaf with various extraction solvents. All of the extracts revealed antimicrobial activity against Bacillus cereus whereas no antimicrobial activities were observed against Escherichia coli, Salmonella typhimurium and Staphylococcus aureus.

• Tuberculosis and Respiratory Diseases
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• v.48 no.5
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• pp.709-719
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• 2000

Background : The different features of high-resolution CT(HRCT) findings of active pulmonary tuberculosis(TB) were studied between acid fast bacilli(AFB) smear or culture positive and negative group. Methods : We prospectively evaluated 36 patients who had been confirmed for active pulmonary tuberculosis by the smear or culture of AFB in sputum(n=25), and changes on serial chest radiographs(n=11). The patients were divided into 3 groups by the results of sputum AFB stain and culture. Group 1(n= 11) is negative in both AFB stain and culture; group 2(n=13) is negative in AFB stain but positive in culture ; and group 3(n=12) is positive in both AFB stain and culture. We evaluated the findings of HRCT in each group randomly. Result : On the HRCT scans, acinar nodule(100%), macronodule(75%), and cavity(75%) in group 3 were more frequently found than group 1(63%. 18%, 9%) and group 2(46%, 15%, 23%)(p<0.05). The centrilobular nodule and branching structure were more frequently observed in group 3(92%) than in group 1(54%)(p<0.05), but were similarly observed in group 2(77%)(p>0.05). AFB positive group was statistically different than the negative group in the HRCT findings with to acinar nodule(100% vs 54%), macronodule(75% vs 17%), and cavity(75% vs 17%)(p<0.05). TB culture positive group was statistically different than the negative group in the HRCT findings with respect to acinar nodule(72% vs 45%) and cavity(48% vs 9%)(p<0.05). Conclusions : HRCT scans are helpful in determining disease acitivity in sputum AFB stain-negative pulmonary tuberculosis. When HRCT shows centrilobular nodule and branching structure, acinar nodule, macronodule, cavity, further studies as sputum induction and bronchoscopy can be performed to determine the presence of bacilli in patients of AFB stain-negative tuberculosis.

• Journal of Veterinary Clinics
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• v.25 no.5
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• pp.324-329
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• 2008

This study was performed to investigate the changes of the serological lipid-related parameters of the rats when they were fed with the high fat diets supplemented with or without rutin for five weeks. Twenty-four Sprague-Dawley male rats ($272.2{\pm}7.2 g$ of body weight) were randomly divided into three groups: control (C) group and two treatment groups. Rats in the C group were fed with the high-fat diet containing 20% lard, 1% cholesterol and 0.5% sodium cholate (w/w) which was modified from the formula of the American Institute of Nutrition-76 (AIN-76) diet. Rats in treatment groups were fed with above diet supplemented with 0.75% rutin (R-0.75) or 1.5% rutin (R-1.5) on the weight to weight basis, respectively. The supplementation of rutin did not induce any significant difference on the final body weight, gain of body weight, the amount of feed intake and the feed efficiency of rats in both control and treatment groups. In addition the values of glucose concentration, total protein, albumin, globulin and albumin/globulin (A/G) ratio showed no significant differences among groups. The values of total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C) in sera of rats in both R-0.75 and R-1.5 groups were lower than those in C group but the significances were showed in only between R-0.75 and C group (p < 0.05 and p < 0.01, respectively). The values of high density lipoprotein-cholesterol (HDL-C) in sera of rats in both R-0.75 and R-1.5 groups were higher than those in C group but the significances were showed in only between R-1.5 and C group (p < 0.01). The values of atherogenic index(AI) of rats in both R-0.75 and R-1.5 groups were the lower than those in C group (p < 0.01 and p < 0.05, respectively). The values of triglyceride in sera of rats showed no significant differences among groups. The values of AST and ALT in sera of rats showed no significant differences among groups. Therefore the supplementation of rutin to high fat diet in rats reduced effectively the serum lipid levels such as TC and LDL-C which were regarded as to cause the cardiovascular diseases, and moreover it elevated effectively HDL-C value which was regarded to protect cardiovascular diseases.