• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.59-66
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• 2007

Three dimensional quantitative structure-activity relationships (3D-QSARs) on the fungicidal activity of N-phenyl-O-phenylthionocarbamate analogues against resistant and sensitive gray mold (Botrytis cinerea) (RBC & SBC) were studied quantitatively using CoMFA and CoMSIA methods. The correlation coefficient and predict- ability of optimized CoMFA model with the atom based fit alignment were better ($r^2$ & $q^2=CoMFA{\gg}CoMSIA$) than that of CoMSIA model. And statistical values of the models on the fungicidal activity against SBC were showed higher ($r^2=SBC{\gg}RBC$) than that of RBC. In CoMFA models, steric field on the activity was more influenced than electrostatic field. And in case of CoMSIA models, the influence of CoMSIA field on the activity against RBC and SBC was differ from each other but the influence of H-bond donor field was same to the two fungi. It is revealed that the selectivity factor with CoMFA model on the fungicidal activity between the two fungi was caused on the difference of steric field. Therefore, it is predicted that the large steric field with meta- and para-substituents on the N-phenyl ring will be improved to the fungicidal activity with SBC.

• Journal of Astronomy and Space Sciences
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• v.34 no.4
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• pp.237-244
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• 2017

Magnetic flux ropes, often observed during intervals of interplanetary coronal mass ejections, have long been recognized to be critical in space weather. In this work, we focus on magnetic flux rope structure but on a much smaller scale, and not necessarily related to interplanetary coronal mass ejections. Using near-Earth solar wind advanced composition explorer (ACE) observations from 1998 to 2016, we identified a total of 309 small-scale magnetic flux ropes (SMFRs). We compared the characteristics of identified SMFR events with those of normal magnetic cloud (MC) events available from the existing literature. First, most of the MCs and SMFRs have similar values of accompanying solar wind speed and proton densities. However, the average magnetic field intensity of SMFRs is weaker (~7.4 nT) than that of MCs (~10.6 nT). Also, the average duration time and expansion speed of SMFRs are ~2.5 hr and 2.6 km/s, respectively, both of which are smaller by a factor of ~10 than those of MCs. In addition, we examined the geoeffectiveness of SMFR events by checking their correlation with magnetic storms and substorms. Based on the criteria Sym-H < -50 nT (for identification of storm occurrence) and AL < -200 nT (for identification of substorm occurrence), we found that for 88 SMFR events (corresponding to 28.5 % of the total SMFR events), substorms occurred after the impact of SMFRs, implying a possible triggering of substorms by SMFRs. In contrast, we found only two SMFRs that triggered storms. We emphasize that, based on a much larger database than used in previous studies, all these previously known features are now firmly confirmed by the current work. Accordingly, the results emphasize the significance of SMFRs from the viewpoint of possible triggering of substorms.

• The Journal of the Korea Contents Association
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• v.19 no.12
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• pp.129-140
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• 2019

This study investigated cyber university students' motivation and demotivation in learning English. Data was collected from a survey of 498 students in a general English course at a cyber university located in Seoul. The survey inquired into participants' English learning motivation and demotivation. To analyze the data, frequency analysis, descriptive statistics, t-test, and ANOVA were used. The findings reveal that among the motivation factors ideal L2 self was the main cause of motivation followed by promotion-based instrumentality. Among the demotivation factors the anxiety factor was found to have the highest mean followed by negative investment value for learning English. The statistical analysis of English learning motivation and demotivation according to the participants' characteristics indicates that, in terms of English learning motivation factors, the male participants' ought-to L2 self was significantly higher than that of the females' and the promotion-based instrumentality of the students who are unemployed was higher than those who are employed. Moreover, the younger the students' age, the higher their competitive motivation and promotion-based instrumentality. In terms of English learning demotivation, the female respondents achieved higher scores in the factors of anxiety, passive learning style, and negative investment value for learning English than their male counterparts. In addition, employed students showed higher demotivation in negative investment value for learning English than those without employment. The findings of this research can be used in developing online English programs for cyber university students who possess diverse learning goals.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.1
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• pp.13-20
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• 2007

This study was performed to provide fundamental data for long-term geomorphic predictions of estuarine sandbars in the Nakdong River. We monitored the geomorphic changes of Jinudo (Jinu Island), which is located on the far-southern side of the first western sandbar. We evaluated the temporal and spatial dynamics of the sandbar and the relationship between erosion and deposit speed with environmental factors. We found that: 1) The south side of Jinudo showed very rapid water channel closing and shoal generation. This phenomenon was more obvious during autumn (September and October) than during spring, with greater water depth reduction and variation between sides. 2) The mean deposit speed for Jinudo was approximately 0.85 mm/day. The deposit speed was 1.32 and 1.26 mm/day for the east and south sides of Jinudo, respectively. The maximum deposit and erosion speeds were 27 mm/day and 26 mm/day in July and December, respectively, on the east side of the island. 3) Mean surface deposit size was 0.18-0.26 mm. The newly deposited sandbar had a rotatively larger deposit size than the original land. 4) Correlation analysis showed that, on the southern side of the island, deposit activity prevailed in the winter due to low precipitation and a northerly wind, while erosion was dominant in the summer due to high water flow and a southerly wind. In contrast, the correlation analysis for the eastern side of the island showed that deposition is dominant when water flow is high. These results indicate that geomorphic dynamics vary among island sides.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.320-331
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• 1996

Electrophoretic comparisons of 482 individuals of Todarodes pacificus from 9 fishing areas were made to estimate genetic variability and differentiation using 17 enzymes. Strong activities were shown by 9 enzymes with 11 gene loci. The 9 sample lots could be divided into 3 genetic groups, based on dendrogram analysis using the Nei's genetic distance. The Summer, Autumn and Winter cohorts were identified as three seperated ecological populations which maintain genetic exchange. It is postulated that either the Summer cohort or the Autumn cohort has indepenently developed a local population that was isolated by hydrographic factors.

• Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.63-70
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• 2010

Two feeding experiments were conducted to investigate the effects of dietary genetically modified (GM) soya and com on growth performance, feed utilization and body composition of juvenile olive flounder, Paralichthys olivaceus and rockfish, Sebastes schlegelii. For each fish species, four isonitrogenous (50% crude protein) and isocaloric (4.1 kcal/g) diets (designated as nGM soya, GM soya, nGM com and GM com) were formulated to contain 20% non-GM (nGM) and GM soya and com. Thirty olive flounder (initial body weight, 15.4${\pm}$0.4 g) and fifty rockfish (initial body weight, 3.1${\pm}$0.02 g) were distributed in each 400 L tank (200 L water) in a flow through system. Each experimental diet was fed to triplicate groups of fish to visual satiation, twice a day (9:00 hand 17:00 h) for 6 weeks. Growth performance was measured every three weeks. No effects of GM feedstuffs on survival were observed. Dietary inclusion of GM feedstuffs did not affect growth performance and feed utilization of fishes, except for rockfish fed GM com. Rockfish fed the GM com diet showed higher weight gain, daily feed intake and daily protein intake than did fish fed the nGM com diet, but no significant differences were observed in final body weight between the dietary treatments. Condition factor, hepatosomatic index, visceral somatic index and body composition were not altered by the inclusion of GM feedstuffs. These results indicate that dietary inclusion of GM soya and com could have no effects on growth performance and feed utilization of juvenile flounder and rockfish. Lower weight gain and feed intake in flounder and rockfish fed the diets containing 20% soya were likely due to anti-nutritional factors, rather than transgenic factors in the feedstuffs. Dietary inclusion of GM soya and com at the level tested did not alter the body composition of fishes. Further studies to investigate the effects of GM feedstuffs on health conditions and the development of fishes, as well as those of residue of transgenic fragments in ambient environments and in animals are necessary for safe use of the ingredients in aquaculture.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.49-57
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• 2018

In this study, we investigated the anti-aging effect of Rosa damascena extract containing low molecular glycoprotein (RELG) converted from the high molecular glycoprotein by bioconversion. Free radical scavenging activities were performed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Antioxidant activities ($IC_{50}$) of RELG and the positive control ascorbic acid were $22.6{\mu}g/mL$ and $21.1{\mu}g/mL$, respectively. For skin cells, $15{\mu}g/mL$ RELG showed 28% antioxidant activity by inhibiting the production of active oxygen species induced by ultraviolet ray and hydrogen peroxide. $15{\mu}g/mL$ RELG prevented 10% the cell death caused by stress in human hair follicle dermal papilla cells (HDPC) and reduced 90% the production of active oxygen species. In addition, the glycoprotein showed not only anti-wrinkle effect but also moisturizing effect by 48% inhibition of matrix metallo proteinase-1 (MMP-1) production by ultraviolet stress and $10{\mu}g/mL$ RELG enhanced 10% neutral lipid synthesis with 44% aquaporin 3 (AQP3) expression, which is moisture factor. In conclusion, the RELG can be used as an anti-aging cosmetic material.

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.1-6
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• 1999

The author studied the soil microarthropoda's fauna, vertical distribution, seasonal fluctuation, and the relationship between the number of soil microarthropoda and environmental factor(pH) in survey area. 3949 soil microarthropoda were collected in survey area. They included Arachnida(48.6%), Collembola(23.5%), Hymenoptera(l9.9%), and Isoptera, etc. Fresh length was the longest(1l3.6 mm) in broad-leaf forest on Mt. Chilgap which is non-industrial complex area, and the shortest(46.8 mm) in pine forest at Yochon industrial complex. The population density of soil microarthropoda was the highest in summer and the lowest in winter. The number of soil microarthropoda was higher in Mt. Keryong and Chilgap, non-industrial complex area, than Yochon and Daesan, industrial complex area. The number of soil microarthropoda increased from spring to summer and decreased from autumn to winter. Vertically, soil microarthropoda were more abundant in the second layer subsoil(0∼5 cm) in spring, in the first layer(5∼10 cm) in summer and autumn, and in the third layer(0∼15 cm) in winter. Diversity index was higher in non-industrial area(1.02) than industrial complex area(0.73). Biodiversity index was the highest in the second soil layer, in pine forest on Mt. Keryong(l.60) and the lowest in the third soil layer, in broad leaf-forest, at Daesan industrial complex(0.24).

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.16-23
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• 2014

Red yeast rice (RYR) has been known to exhibit various biological effects, including anti-hyperlipidemia, antioxidant, anti-tumor, and anti-inflammtory activities. Oxidative stress is a main risk factor in the development of cardiovascular disease, such as atherosclerosis. Therefore, the aim of this study was to investigate the possible hypolipidemic and antioxidant effect of RYR on rats fed a high-cholesterol diet supplemented with either 0.2%, 1%, or 5% RYR for 4 weeks. We measured lipid profiles in the plasma and liver, antioxidant enzyme activities in plasma and erythrocyte, gene expression of antioxidant enzymes in the liver, and oxidative DNA damage in lymphocytes. The group supplemented with 0.2% RYR had total cholesterol level in plasma decreased by 24%, while the group supplemented with 5% RYR had high-density cholesterol increased by 20% compared to the control. The antioxidant enzyme activities were also affected by RYR supplementation. Total superoxide dismutase activities in plasma significantly decreased by 11% in the 1% RYR group, while these activities in the liver significantly decreased by 16% and 21% in the 1% and 5% supplemented group compared to the control, respectively. Glutathione peroxidase activities in plasma and erythrocytes increased 13% and 48% in the 1% RYR group, respectively. Catalase (CAT) activity in erythrocytes significantly increased by 49% and 68% in the 1% and 5% RYR group compared to the control, respectively. The gene expression of CAT was up-regulated 7.9 fold compared to the control in the 5% RYR supplemented group. These results suggest that RYR can control hyperlipidemia by improving the lipid profile and modulating oxidative stress.

• Progress in Superconductivity and Cryogenics
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• v.21 no.4
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• pp.1-5
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• 2019

We investigated the effect of Fe₃O₄ addition on the critical temperature of (Bi, Pb)-2223 polycrystalline samples. Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_10+δ + x wt. % Fe₃O₄ (x = 0.0, 0.2, 0.4, 0.6, and 0.8) samples were prepared by using a solid-state reaction method. The analysis of X-ray diffraction data indicates that as Fe₃O₄ is added, dominant phase of the sample changes from Bi-2223 to Bi-2212 with an increasing Bi-2201 phase. The transition temperature of the samples drastically decreased with the Fe₃O₄ addition. The resistance data of samples with x = 0.2 and 0.4 showed a double transition indicating a coexistence of Bi-2223 and Bi-2212 phase while the samples with x = 0.6 and 0.8 showed a single transition with a semiconducting behavior. This phase transition may originate from changes in local structure of the Bi-2223 system by Fe₃O₄ addition. Analysis of the pair distribution function of the Cu-O pair in the CuO₂ plane calculated from extended X-ray absorption fine structure data revealed that the oxygen coordination of copper ion changes from CuO₄ planar type (x = 0.0 - 0.4) to CuO₅ pyramidal type (x = 0.6, 0.8). The correlated Debye-Waller factor, providing information on the atomic disorder within the CuO₂ plane, shows an inverse relation to the coordination number. These results indicate that addition of Fe₃O₄ changes the oxygen distribution around Cu in the CuO₂ plane, causing a phase transition from Bi-2223 to more stable Bi-2212/Bi-2201 phases.