• Journal of Preventive Medicine and Public Health
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• v.25 no.1 s.37
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• pp.13-25
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• 1992

This study was conducted to investigate the mechanism of protective effect by sodium selenite in methylmercuric chloride neurotoxicity, increasing intracellular $Ca^{2+}$concentration of the neuron. Methylmercuric chloride of 3mg/kg of body weight was administered simultaneously with sodium selenite of 5mg/kg and pretreatment of sodium selenite via intraperitoneal injection to rats. Also, effect of methylmercuric chloride($25{\mu}M,\;50{\mu}M,\;100{\mu}M$) and sodium selenite($200{\mu}M$) on free intrasynaptosomal $Ca^{2+}$ concentration were studied using the fluorescent $Ca^{2+}$ indicator fura -2 in vitro. After the treatment, at 6, 24, and 48 hours later, mercury in the cerebral cortex, liver and kidney tissues, succlnic dehydrogenase activities, adenosin-5'-triphosphate concentration, acetylcholinesterase activities, and intracellular $Ca^{2+}$ concentration in the cerebral cortex were determined in vivo. Cerebral synaptosomes of rats were incubated with methylmercuric chloride and sodium selenite in Hepes buffer for 10 minutes and free intrasynaptosomal $Ca^{2+}$ concentration were measured with fura-2 in vitro. The results were summarized as follows ; 1. The combined administration of $CH_3HgCl$ and $Na_2SeO_3$ and pretreatment of $Na_2SeO_3$ according to time significantly more increased in the cerebral cortex and decreased in the liver, kidney mercury concentrations compared to the administration of $CH_3HgCl$ only. 2. The combined administration of $CH_3HgCl$ and $Na_2SeO_3$ and pretreatment of $Na_2SeO_3$ increased more succinic dehydrogenase and acetylcholinesterase activities compared to the administration of $CH_3HgCl$ only. Particularly pretreatment of $Na_2SeO_3$ significantly more compared to the administration of $CH_3HgCl$ only. The concentration of adenosine-5'-triphosphate in $Na_2SeO_3$ treatment groups revealed a favourable effect compared to the administration of $CH_3HgCl$ only. 3. Intracellular $Ca^{2+}$ concentration in administration of $CH_3HgCl$ only was increased significantly more than control group in all test hours but was increased significantly more at 48 hours only after treatment in combined administration of $CH_3HgCl$ and $Na_2SeO_3$ and pretreatment of $Na_2SeO_3$ according to time interval more decreased significantly intracellular $Ca^{2+}$ concentration compared to the administration of $CH_3HgCl$ only. 4. Free intrasynaptosomal $Ca^{2+}$ concentration in the combined administration of $CH_3HgCl$ and $Na_2SeO_3$ was decreased ($24%{\sim}40%$) significantly more than the administration of $CH_3HgCl$ only. From the above results, the specific dosage of $Na_2SeO_3$ decreased increment of intracellular $Ca^{2+}$ concentration induced by administration of $CH_3HgCl$. These findings suggest the protective mechanism of $Na_2SeO_3$ on the neurotoxicity of $CH_3HgCl$.

• Research in Plant Disease
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• v.23 no.2
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• pp.159-167
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• 2017

This study was conducted to evaluate the control efficacy of the organic farming materials on cucumber scab caused by Cladosporium cucumerinum PT1 (KACC 48094). The antifungal activities in vitro as well as the suppressive effect of 43 organic farming materials on the spore germination and germ tube growth by inoculating spore suspension on cucumber seedlings in vivo were investigated. Thirteen organic farming materials inhibited the mycelial growth of C. cucumerinum and nine of these were microbial agents. In the screening using cucumber seedlings, six organic farming materials were very effective with control efficacy value of 90%. Among them, Bacillus amyloliquefaciens M27 provided suppressive effect on both mycelial growth and spore germination against cucumber scab. Finally, nine organic farming materials were selected to test the protective and curative effects, and all chosen organic farming materials significantly suppressed disease incidence when applied in the preventive action, in comparison with the curative action. Especially, Bordeaux mixture I and III gave excellent protective control efficacy with control values of 96.7% and 73.3%, respectively, whereas its curative control effect was significant low. Among these, only Thymus quinquecostatus+Sophora extract showed curative activity, although the control value was as low as 50%. This study suggests that cucumber scab can be controlled by some organic farming materials in the farmhouses under comparatively cold and wet condition and protective treatment is more important and efficient.

• Korean Journal of Poultry Science
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• v.11 no.2
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• pp.99-108
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• 1984

The experiment was performed with the aim to study not only the effect of protein levels of basal diets on apparent and true metabolizable energy (AME and THM), AME of Farrell(AME$\_$F/), and corrected AME$\_$FC/ values of corn and soybean meal but also the effect of collection time of excreta on AME and TME values of corn and soybean meal. The AME$\_$F/ and AME$\_$FC/ values of test materials were determined through rapid AME bioassay, and AME and TME by the TME bioassay. The protein levels of basal diets had range from 10% crude protein(CP) to 30% CP. The results obtained were as follows; 1. The AME$\_$F/ values of basal diets showed much difference among treatments (P＜0.05) but those of corn and soybean meal had no significant differences (P＞0.05)and the AHE$\_$FC/ values of basal diets were proved to be variable according to level of protein of the diets. the AME$\_$FC/ values of com were not different while those of soybean meal in 20% and 30% were reduced significantly(P＜0.05). 2. The protein intake/bird/day did not differ significantly due to variation of feed intake using rapid AME bioassay. 3. The protein levels of basal diets did not influence upon the AME value of basal diets, corn and soybean meal (P＞0.05), and no clear trend was found in the TME values of corn and soybean meal because of the variation of metabolic fecal energy plus endogenous urinary energy (FEm＋UEe) losses fed different diets. 4. Collection time of excreta affected the AME and TME values of basal diets in 10, 15, 20% CP treatments, but the AME and TME of corn and soybean meal were not affected by collection time; Thus, a time of 24 hours was mough for 24 hr to clean the digestive tract when fed corn and soybean meal substituted diets regardless of protein levels.

• Journal of the Korean Society of Radiology
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• v.8 no.5
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• pp.231-240
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• 2014

The purpose of this study were to analyze that the Seoul neuropsychological screening battery (SNSB) for the evaluating cognitive assessment of the Parkinson's disease patients with mild cognitive impairment (PD-MCI) and the changes of the cerebral ventricle volume in the brain magnetic resonance imaging (MRI), and we has been bring forward the guideline to determine the diagnostic criteria for the PD-MCI. To achieve this, we was diagnosed with Parkinson's disease patients (PD-MCI group: 34 patients; Parkinson's disease with normal cognition, PD-NC group: 34 patients) to perform the SNSB test for the attention, language, memory, visuospatial, and frontal/executive functions and the brain MRI. Additionally, to compared the change of the cerebral ventricle volume, we performed the brain MRI for the 32 normal control (NC) group. The volumetric analysis for a specific cerebral ventricle performed by using Freesurfer Ver. 5.1 (Massachusetts general Hospital, Boston MA, USA). As a results, compared to the PD-NC group, the PD-MCI group were statistically significant reduction in the ability to perform the memory and the visuospatial function (p<0.05). The volumetric changes for a specific cerebral ventricle were statistically significant variation in the left and right lateral ventricle, left and right inferior lateral ventricle, and 3rd ventricle. Although, in order to compared the objectification, the normalized percentage applied to the volumetric changes showed to extend the PD-MCI group than the PD-NC group. Specially, the left and right ventricle extension for the PD-MCI patients conspicuously had showed a quantitative linear relationship between the memory and the visuospatial function for the SNSB (r>0.5, p<0.05). Therefore, we were able to judge the diagnostic criteria of the PD-MCI through that can observe the volumetric variation of the specific cerebral ventricle by using Freesurfer in brain MRI, and to analyze the correlation between the SNSB.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.419-427
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• 2005

For the purpose to verify the physico­chemical properties of Korean waxy wheat, comparative analyses between waxy wheat lines and their respective maternal parents were performed on mixing and pasting properties, and flour particle sizes. The particle sizes of waxy wheat flour were significantly larger than those of their parents when milled in a same condition. Although the protein contents of flour in waxy wheat lines tested were high as much as those of bread wheat, the quality parameters showed lower baking uses based on sedimentation volumes and mixing characteristics. Waxy flour required more water than non-waxy flour to obtain the proper mixogram. Waxy wheat flour showed more or less higher onset pasting temperatures and much higher breakdown viscosities than their respective parent flour in the Rapid Viscograph test. Moreover, peak viscosity temperatures and final viscosities were dramatically reduced in waxy wheat lines by showing $79.4 - 81.7^{\circ}C$ and 101 ­116.9 RVU, respectively, compared to their parents in that the temperatures above $95^{\circ}C$ and the viscosity ranges of 148 -171.8 RVU.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.477-483
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• 2008

$La_{0.7}Sr_{0.3}Co_{0.2}Fe_{0.8}O_{3-{\delta}$ oxide was synthesized by a citrate method and a typical dense membrane of perovskite oxide has been prepared using as-prepared powder by pressing and sintering at $1300^{\circ}C$. Precursor of $La_{0.7}Sr_{0.3}Co_{0.2}Fe_{0.8}O_{3-{\delta}$ prepared by citrate method was investigated by TGA and XRD. Metal-citrate complex in precursor was decomposed into perovskite oxide in the temperature range of $260{\sim}410^{\circ}C$ but XRD results showed $SrCO_3$ existed as impurity at less than $900^{\circ}C$. Electrical conductivity of membrane increased with increasing temperature but then decreased over $700^{\circ}C$ in air atmosphere ($Po_2=0.2atm$) and $600^{\circ}C$ in He atmosphere ($Po_2=0.01atm$) respectively due to oxygen loss from the crystal lattice. The oxygen permeation flux increased with increasing temperature and maximum oxygen permeation flux of $La_{0.7}Sr_{0.3}Co_{0.2}Fe_{0.8}O_{3-{\delta}$ membrane with 1.6 mm thickness was about $0.31cm^3/cm^2{\cdot}min$ at $950^{\circ}C$. The activation energy for oxygen permeation was 88.4 kJ/mol in the temperature range of $750{\sim}950^{\circ}C$. Perovskite structure of membrane was not changed after permeation test of 40 h and the membrane was stable without secondary phase change with 0.3 mol Sr addition.

• Journal of the Korean Society for Library and Information Science
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• v.18
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• pp.277-325
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• 1990

The purpose of this study was to determine the effectiveness of instructors' utilization of the reserve collection in the university library. To accomplish this, an experiment-and-questionnaire study was done by selecting an experimental group for whom the teaching method utilizing the reserve collection was used and a control group for whom the method was not used. An experimental group and a control group studied were as follows: (1) Students take the 'Comparative Politics' course in the Department of Political Science. (2) Students take the 'History of 'English Literature' course III the Department of English Language and Literature. The data to test the hypothesis were analyzed by SPSS/PC+ routine. The results are as follows: (1) There were significant differences between the experimental group and the control group in academic achievement(T(228)=6.69, P<.01). To investigate the difference in effect by major, the one-way analysis of variance was employed. According to the results, there were significant differences between the experimental group and the control group In the Department of Political Science and the Department of English Language & Literature. Therefore, students for whom the teaching method utilizing the reserve collection was used have higher academic achievement than those for whom the method was not used. (2) As for the degree of utilizing the library and its materials, there were significant differences between the experimental group and the control group(T(228)=8.87, P<.01). As for the results of the one-way analysis of variance to investigate the difference in effect by major, there were significant differences between the experimental group and the control group in both departments. As for the degree of utilizing library catalogues and bibliographical tools, there were significant differences between the experimental group and the control group(T (228)=8.55, P<.01). As stated earlier, the one-way analysis of variance to investigate the difference in effect by major has shown that there were significant differences between the experimental group and the control group in both departments. As for the degree of sincerity in doing homework and writing papers, there were significant differences between the experimental group and the control group(T(176)=8. 03, P<.01). To investigate the difference in effect by major, the one-way analysis of variance was again employed. According to the results, there were again significant differences between the experimental group and the control group in both departments. So, the students for whom the teaching method utilizing the reserve collection was employed used library catalogues and bibliographical tools much more than those for whom the method was not employed, and were more sincere in doing homework and writing papers. (3) There were also significant differences between the experimental group and the control group in degree of satisfaction in taking the course (T (228) = 6.61, P<.01). The results of the one-way analysis of variance to investigate the difference in effect by major was that there were significant differences between the experimental group and the control group in both departments. Therefore, the degree of satisfaction of students who were taught by the teaching method utilizing the reserve collection is higher than that of those who were not taught by the method. On the other hand, the responses of the experimental groups of two departments as to the degree of satisfaction with their teaching method was investigated. The result shows that students who took the 'Comparative Politics' course in a small class which employed the seminar method were higher in degree of satisfaction with the teaching method than students who took the 'History of English Literature' course III a large class which employed a lecture-oriented teaching method.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.370-378
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• 1983

Changes of protein and amino acids composition in improvement-Meju inoculated with Aspergillus oryzae were emamined at various time intervals over 6-day test period. To investigate those changes systematically, Disc gel electrophoresis, gel fiteration and amino acid analyzer were used. Following results were obtained; 1. Nitrogen solubility of the soybean meal in $Na_{2}SO_{4},\;MgSO_{4},\;Na_{2}CO_{3},\;NaCl\;and\;Na_{2}HPO_{4}$ solutions of various concetrations were determinated. The salt soluble protein of soybean meal was highly dispersible on 0.4M $Na_{2}SO_{4}$ solution and the extractability of protein was 33%. 2. From the quantitative fractionation of soybean proteins, albumin content (46.0%) was highest followed by globulin (33.9%), glutelin (19.5%) and prolamin (2.4%). During Meju incubation period, albumin and prolamin increased gradually but glutelin decreased. Globulin content was not changed substantially. 3. When albumin was fractionated by Sephadex G-200, the following results were obtained. Soybean albumin showed fraction which was reduced to 3 fraction at 0-day of incubation. The number of fraction, however increased to 8 after 6-day of incubation. 4. Amino acids of albumin in soybean and Meju appeared to be 17 kinds. Glutamic acid and aspartic acid were the highest. In amino acid composition of cooked soybean albumin, arginine, aspartic acid, glutamic acid and glycine remained higher than those of Meju throughout incubation period. 5. The major fraction of albumins from soybean and Meju fractionated by Sephadex G-200 showed 17 kinds of amino acid. Aspartic acid and glutamic acid were the highest. During Meju incubation period, the change of amino acid composition was investigated; threonine, serine, lysine, histidine, alanine, isoleucine, leucine, phenylalanine and $NH_3$ was increased gradually, the others decreased. 6. According to the electrophoretic pattern, soybean protein showed 13 bands which decreased to 3-after cooking. During incubation, those bands increased gradually to 10 bands after 6-days.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.3
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• pp.85-91
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• 1988

A field experiment was conducted to determine the effects of shading degrees (0: full sunlight, 25, 50 and 75%) on the proximate components, cell wall constituents (CWC), digestibility, water soluble carbohydrates (WSC) and nitrate nitrogen ($NO_3$-N) concentration of grasses grown in forest. For the test different artificial shading houses were established and pasture species used were orchardgrass, timothy, perennial ryegrass and ladino clover. The experiment was performed at LES in Suwon. 1985. 1. Considering proximate components, CWC and digestibility of grasses, ladino clover showed the best quality, and then perennial ryegrass. 2. The contents of crude protein, crude ash, and digestibility of grasses were increased with shading, regardless of pasture species. As the shading degrees are increased, the contents of crude fiber in orchardgrass, perennial ryegrass and timothy were decreased, while that in ladino clover was increased with shading. 3. Grasses grown in spring showed higher digestibility than those grown in summer season. 4. The content of WSC was the highest in perennial ryegrass, and then ladino clover, orchardgrass, and timothy, in that order. Also WSC was decreased as the shading degrees are increased. 5.The content of $NO_3$-N was the highest in perennial ryegrass, and then orchardgrass, ladino clover and timothy, in that order. Also the $NO_3$-N was significantly increased with higher shading level. In the regression equation between shading degrees and $NO_3$-N ($r^2$=0.90**, TEX>$r^2$=0.95**), shading degree of 43 to 44% was critical level, causing nitrate poisoning to animal. 6 Considering grass quality, dry matter yield and $NO_3$-N, less than 40% of shading degree (over 60% of full sunlight) was desirable for better grassland improvement, management and utilization in the forest.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.5
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• pp.1-8
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• 2014

Structures requiring chemical resistance are usually coated with surface protecting agents, but the cost for maintenance and re-construction is incurred due to the low durability. Therefore, in this study, sulfur was polymerized and the performance was examined so that it could be used as the concrete surface protecting agents for structures requiring chemical resistance. The evaluation results indicated that for the spray of the sulfur polymer surface coating agents, the application of the gravity type was appropriate; and for the number of coating times, about 3 cycle spray gave the best results. For the surface condition of the concrete to be coated with the surface protecting agents, outstanding quality was obtained above room temperature ($20{\sim}30^{\circ}C$), and the bond strength increased as the temperature increased. The evaluation results of the strength characteristics depending on the filler content of the surface protecting agents indicated that about 20~40% filler mixing contributed to the strength improvement as it reduced the shrinkage of the sulfur polymer. Also, the mixing of silica showed larger increase in the bond strength than the mixing of fly ash, and the most outstanding bond strength characteristics could be obtained by the mixing of both silica and fly ash. In the case of the chemical resistance, the strength reduction was minimized and outstanding chemical resistance was obtained when the fly ash and silica were substituted by 20%, respectively. The performance evaluation of the chloride ion penetration indicated that for the specimens coated with the sulfur polymer surface protecting agents, the chloride ion penetration resistance increased by 29~48% compared to the specimen without the coating of the surface protecting agent. The examination of the coating condition of the surface protecting agents, compressive strength, bond strength, chemical resistance, and salt damage resistance indicated that in the range of this study, the optimal level was when the silica and fly ash were substituted by 20%, respectively, as the filler for the sulfur polymer.