• Korean Journal of Weed Science
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• v.9 no.3
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• pp.238-244
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• 1989

The experiment was carried out to evaluate the herbicidal properties of dithiopyr(3, 5-pyridine dicarbothioic acid-2-(difluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-S,S-dimethyl ester). Weeding effect of dithiopyr was determined under various factors such as dosage, soil type, leaching amount, temperature, water depth, overflow time, and application time and method. Dithiopyr showed very high phytotoxic activity on most major annuals weeds, expecially Echinochloa crus-galli and Monochoria vaginalis. Excellent control of Echinochloa crus-galli was obtained at 0.04kg a.i./ha with preemergence application and 0.12kg a.i./ha with early post-emergence application (12 DAT ; Echinochloa crus-galli of 1.5 leaf stage). Weeding effect of dithiopyr decreased when applied at the soil surface 2days before transplanting. Soil type, leaching amount, temperature, water depth, overflow time did not affect the weeding effect.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.152-158
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• 2013

Dandelion (Taraxacum officinale) is a member of family Asteraceae that grows all over the Korea. Recently, dandelion was cultivated for medicinal crops because of its positive medicinal effects. However, dandelion is considered as a troublesome weed in grass lawns of golf course and orchards. This study was conducted to investigate the effect of plant growth regulators [gibberellins ($GA_3$); kinetin; salicylic acid (SA); ethephon)] with different concentration on seed germination control of dandelion. Seed germination rates were increased in all concentration of $GA_3$ and kinetin treatment compared to control. In the 0.5 mM of ethephon application, seed germination rate was more increased than that of control while seed germination rate was reduced in 1.0 and 1.5 mM of ethephon treatments. Seed germination rate was significantly decreased with different SA dilutions compared to control. The germination rate was more reduced when SA was applied in combination with $GA_3$ than only SA treatments.

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.400-406
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• 1997

Greenhouse studies were conducted to evaluate the tolerance of 42 pepper cultivars to postemergence applications of bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide]. Cultivars, Jopoong, Singsing House, Sweet Green, Kwangbok, and Ilcheon showed relatively tolerant response to bentazon, while cultivars, Dahhong, Early Glory, Korea, Cheongyang, Nostalgia, and Daejanggyeong were susceptible ones to it. At rates over 2.40 kg ai/ha, the tolerant cultivars appeared to be clearly or more tolerant than the susceptible cultivars. For the determination of growth inhibition by bentazon, the concentration required to reduce growth by 50% (GR_(50)) was 2.00 to 2.40 kg ai/ha for susceptible cultivars, and 10.00 to 12.00 kg ai/ha for tolerant cultivars. Moreover, the herbicide rate required to inhibit growth by 50% $(I_{50})$ was 2.40 kg ai/ha for susceptible cultivars and 9.60 kg ai/ha for tolerant cultivars, respectively. On the $I_{50}$ and $GR_{50}$ estimates of growth, the tolerant cultivars were 5- to 6-fold more tolerant to bentazon than susceptible ones.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.71-77
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• 2011

This study was conducted to predict the yield loss of red pepper and to determine the economic weed thresholds levels for red pepper cultivation field from competition with the most serious weeds, Echinochlor crus-galli (L.) P. beauv. (barnyard grass) and Chenopodium album L. (goosefoot) in Youngyang of Korea. Crop yield as a function of weed density was predicted by using a rectangular hyperbola, and their economic threshold levels were determined by using the equation developed by Cousens (1987). The red pepper yield loss models of weeds were predicted as y=317.0 kg/ (1+0.1707x), $R^2$=0.895 in E. crus-galli and y=323.2 kg/(1+0.2900x), $R^2$=0.896 in C. album L.. Economic thresholds calculated using Cousens' equation was negatively related with the competitiveness of weed. Economic thresholds of each weed were calculated as 6.5 plant $100m^{-2}$ in E. crus-galli, and 3.7 plant $100m^{-2}$ in C. album L..

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.74-77
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• 1987

This study was undertaken to elucidate the behavior of herbicide bensulfuron methyl [ methyl 2-[[[[[(4, 6-dimethoxy pryrimidine-2yl) amino] carbonyl] amino] sulfonyl] methyl] benzoate] in soils under flooded conditions using the test plant Monochoria vaginalis Pres 1. Besulfuron methyl moved to 3cm depth in clay loam soil and 4 cm depth in sandy loam soil. Herbicide-treated layer was found 0 to 2 cm profile in the former and 0 to 3 cm profile the latter. The half life (GR50) was 87 days in clay loam soil and 78 days in sandy clay loam soil. The period of inactivation lasted for 110 days in clay loam and 100 days in sandy clay loam soil.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.23 no.2
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• pp.45-68
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• 2012

Archives have directly and indirectly served for memory. What is collected in archives, how it is presented to users, and how users understand and use the documents affects how a given society remembers its past. Some archival scholars see that how users interpret documents from their perspectives and by social interests may play a central role in constructing social memory because memories are often triggered by individual and social concerns of the present time. Therefore, knowing what causes users to seek for a certain materials, how they use those materials and why can offer a clue to learn how archives serve for social memory. In the Web space, the interaction between users and archives/archival materials can be easily observed. Beyond making access simple for users and promoting archival documents using Web technology, archives can serve the broader purpose of memory by skillfully exploiting the characteristics of Web 2.0 and digital cultures in a way to observe how users engage in and contribute to archival contents available on the Web. This study examines the discourses on memory in the archival context, and in particular, how archives can serve as platforms for memory within the new environment of Web 2.0 technologies. It surveys discussions on memory in relation to archives, history, and evidence, focusing on the user and use context as it is represented in the archival literature. This paper discusses how that technology provides features that allow us to see collective memory being constructed in the archives, and presents examples of how the Web 2.0 technology can structure the way users share their memories in building a larger narrative around the archive.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5155-5159
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• 2012

Objective: To investigate the association between CD105 and tumor cell proliferation in salivary gland tumors. Methods: In this study, 59 samples of salivary tumors from Khalili Hospital archive, including 20 cases of pleomorphic adenoma (PA), 20 cases of mucoepidermoid carcinoma (MEC) and 19 cases of adenoid cystic carcinoma, as well as 10 cases of normal salivary gland tissue, were reviewed by immunohistochemistry (IHC) for CD105 and Ki67 staining. Results: CD105 positive vessels were absent in normal salivary gland tissue in the vicinity of tumors (51.6% of all tumors were positive). There was a statistically significant difference in frequency of CD105 staining between PA and malignant tumors and between four groups of different lesions (p<0.000) being highest in MEC. Intratumoral microvessel density was also elevated in malignant neoplasms ($2.61{\pm}3.1$) as compared to PA ($0.46{\pm}0.6$). Normal salivary glands did not express Ki67. There was a statistically significant difference in frequency and percentage of Ki67 immunoreactivity in malignant neoplasms (86.5% and $10.7{\pm}10.8$ respectively) compared to PA (50% and $0.78{\pm}0.2$) and among the four groups values were highest in MEC (p<0.000). Conclusion: n this study, it was observed a higher rate of angiogenesis and cellular proliferation was noted in malignant tumors compared to benign tumors, but no correlation was observed between these two markers.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.182-186
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• 1988

This study was conducted to level up the tolerance of tobacco plant against bialaphos herbicide through tissue culture. The relatively good shoot regeneration from the subcultured calli treated with bialaphos at 0.5 ppm was observed in old the tobacco varieties tested such as NC 82, BY 4 and KA 101. However, at the treatment of bialaphos 1.0 ppm, shoot regeneration was only made in KA 101 variety, showing better regeneration than that of untreated one, When these shoots were transfered to the medium containing of bialaphos 10.0 ppm, the percentage of living shoots (i.e. tolerant plant) was very low, showing 2.43% in NC 82, 2.76% in KA 101 and 0.78% BY 4. Calli were induced and multiplied from leaf petiole of the above tolerant plants even under 2.5ppm of bialaphos, showing an average of 9% in NC 82 and 16% in KA 101 as compared with the untreated control. No calli were induced from tolerant plants as bialaphos concentration increased up to 5.0 ppm. Direct shooting from leaves of the above tolerant plants, that is selected at 10.0ppm of bialaphos treatment, was observed even under 10.0ppm of bialaphos treatment both in NC 82 and in KA 101 varieties, indicating that tolerance of tobacco plants against bialaphos can be greatly increased.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.31-37
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• 2012

This study was conducted to make the rice yield prediction model system as affected by densities of Aneilema keisak and Aeschynomene indica and to determine their economic threshold levels in flooded direct-seeded rice. When the density of A. keisak was 8 plants per $m^2$, the yield of rice reduced to 8% and as the density increased up to 96 plants per $m^2$, the reduced rate of rice yield reached to 45% and in A. indica, the reduced rate of rice yield were 20 and 77%, respectively. The rice yield loss models of A. keisak and A. indica were predicted as Y=553.2 kg (1+0.00913X), $R^2=0.912^{**}$ and Y=567.9 kg/(1+0.04434X), $R^2=0.961^{**}$, respectively. Economic threshold levels calculated using cousens' equation were 3.0 plants per $m^2$ in A. keisak and 0.6 plants per $m^2$ in A. indica.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.38-43
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• 2012

This study was conducted to predict the yield response of red pepper and to determine the economic weed threshold levels for red pepper cultivation field from competition with the most serious weeds, Amaranthus patulus and Digitaria ciliaris in Youngyang of Korea. Crop yield as a function of weed density was predicted by using a rectangular hyperbola, and their economic threshold levels were determined by using the equation developed by Cousens (1987). The red pepper yield loss models of weeds were predicted as y=304.7/(1+0.063x), $R^2$=0.967 in D. ciliaris and y=281.3/(1+0.1723x), $R^2$=0.952 in A. patulus. Economic thresholds calculated using Cousens' equation were negatively related with the competitiveness of weed. Economic thresholds of each weed were calculated as 18.2 plant $100m^{-2}$ in D ciliaris, and 7.2 plant $100m^{-2}$ in A. patulus.