• Korean Journal of Weed Science
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• v.1 no.1
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• pp.30-43
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• 1981

On unwedded paddy fields, six cropping patterns of rice cultivation, namely direct broadcast seeding, direct row seeding, machine transplanting, early season hand transplanting, standard season hand transplanting, and late season hand transplanting, were detected with two representative rice cultivars (Milyang 23 and Sadominori) to estimate the comparative fluctuation patterns of weed flora. As a result, number of emerged weed species, most crowding stages, differences of weed growth among cropping patterns, possible tendencies of competition in plant heights among plant groups, variations in Importance Values, and Simpson's Index analysis were discussed, respectively.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.282-290
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• 2010

The objective of this research was to discover the best method for weed management in environment-friendly rice paddy fields through the study on the effect of weed control and injury levels of rice plants as affected by size, input time, and input amount of golden apple snail (GAS). The efficacy of weed control as affected by GAS when applied at 5, 10, and 15 days after transplanting (DAT) was 98, 89, and 58%, respectively. The efficacy of weed control had declined as late the input time of GAS. On the other hand, the efficacy of weed control as affected by rice bran followed by GAS treatment was higher than by GAS treatment alone. Weed species such as Persicaria hydropiper, Echinochloa crus-galli, Scirpus juncoides, and Monochoria vaginalis were not completely controlled by GAS when applied late. Input amount and time of adult GAS (70 days after hatching) for effective weed control were 3 kg $10a^{-1}$ at 5 DAT, 6-7 kg $10a^{-1}$ at 10 DAT, and 7 kg $10a^{-1}$ at 15 DAT. Input time and amount of young GAS (35 days after hatching) for effective weed control were 0 day after harrow (DAH) and 1 kg $10a^{-1}$, respectively. The young GAS when applied 0 DAH at 1 kg $10a^{-1}$ provided 100% control of P. hydropiper, E. crus-galli, S. juncoides, M. vaginalis, Ludwigia prostrata, Eleocharis kuroguwai, Sagittaria trifolia and Cyperus difformis. The rice foliar injury caused by adult (3 kg $10a^{-1}$) and young (1 kg $10a^{-1}$) GAS were 5-7% and 1% respectively. There was no significant difference in rice injury by size and input amount of GAS on plant height and number of tiller. These data indicate that the young GAS when applied 1 kg $10a^{-1}$ at 0 day after harrow was the best method for weed management in environment-friendly rice paddy fields.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.4
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• pp.439-445
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• 2017

In recent years, change in life patterns gave rise to an increase in the number of families with companion animals, and as a result, frequent dermatophytes infections have been reported. Microsporum canis, Trichophyton mentagrophytes, and Trichophyton verrucosum, are among these species of zoophilic dermatophytes. Trichophyton mentagrophytes are transmitted to humans by contact with wild animals. Infection from it causes strong inflammation in humans. Conversely, Trichophyton verrucosum is transmitted by contact with cattles. Microsporum canis will become latent carriers in cats or dogs, causing infectious diseases when it comes in contact with humans. We investigated zoophilic dermatophytes isolated according to annual, sex, age, season, body sites, and clinical types between 2010 and 2016. According to our results, the isolation rate of zoophilic dermatophytes was 0.37%, among which, 88 T. mentagrophytes, 228 Microsporum canis, and 18 Trichophyton verrucosum were isolated in human. It is interesting to note that Microsporum canis has been on the rise since 2014. Microsporum canis and Trichophyton verrucosum were highly isolated in females, but T. mentagrophytes was isolated similarly in both sexes. According to an age-based survey, the isolation rate was higher in children younger than 10 years. Our results is a valuable data for predicting and studying the isolation of zoophilic dermatophytes in the future.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.353-357
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• 2003

We studies seed set in the interspecific F1 /backcross hybrids of Lilium species. In the interspecfic hybrid of L. longiflorum cv. Gelria with L.${\times}$ fomolongi cv. Raizan,93％ fruit set was obtained by stigmatic pollination in comparison to 53％ from cut-style pollination. Accordingly, the number of seed set resulting from stigmatic and cut-style pollination was 147 and 53, respectively. Pollination o( both stigmatic and cut-style pollination resulted in 47％ fruit set in the hybrid of L. longiflorum cv. Lorina with L.${\times}$ fomolongi cv. Raizan. However, stigmatic pollination formed 413 seeds, whereas only 24 seeds were obtained by cut-style pollination in this cross. The hybrid of L.${\times}$ fomolongi cv. Raizan with L. longiflorum cv. Come set 40％ fruit with a total of 43 seeds by stigmatic pollination. However, no fruit set was observed in cut-style pollination in this hybrid. Backcrossing the F1 hybrid by cut-style pollination of L. longiflorum cv. Lorina ${\times}$ Asiatic hybrid cv. Chicago with the latter parent led to 53％ fruit set, and 109 embryos were obtained. Likewise, backcrossing following cut-style pollination of L. longiflorum cv. Lorina ${\times}$ Asiatic hybrid cv. Corsia with the latter parent formed 67％ fruits and 107 embryos. However, in the remaining interspecific hybrids, cut-style pollination set no fruit.

• Korean Journal of Weed Science
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• v.15 no.4
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• pp.289-297
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• 1995

Field experiments were conducted to evaluate the competitive characteristics of weeds with direct-seeded rice. In both dry- and water-seeded rice a weeds) started to grow over the plant height of rice from 45 days after seeding, and there was a great difference in plant height between rice and weeds from 75 days after seeding. Dry weights of weeds drastically increased from 30 days after seeding in both dry- and water-seeded rice, and the increase of dry weight was faster in dry-seeded rice than in water-seeded rice with time. Although weeds competed with rice at earlier growth stages, they did not reduce rice yields and its components until competition period of 75 days after seeding. Required period of weed free at the beginning of the season was 30 to 45 days from seeding in order to avoid any yield loss. The numbers of panicle per plant, spikelets per panicle, grain weight and yield of rice in dry-seeded rice had highly negative correlations with the growth ratios of Echinochloa crus-galli, Ludwigia prostrata, Cyperus difformis, Bidens frondosa, and Cyperus serotinus. In water-seeded rice, the number of plants, panicle per plant, spikelets per panicle and yield had highly negative correlations with growth rate of Echinochloa crus-galli, but the percentage of filled spikelet had negative correlation with Cyperus difformis. Research indicated that in direct-seeded rice weed competition with rice started from 30 days after seeding and significant yield loss by weed competition occurred from 75 days after seeding.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.1
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• pp.23-28
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• 2011

Resveratrol has been associated with reduced cardiovascular disease and reduced cancer risk. This phytochemical has been reported in a number of plant species including grapes, peanuts and pine trees in response to stress such as fungal infection, heavy metal ions or UV irradiation. The objective of this study was to determine the resveratrol contents in leaves of mulberry varieties at different collecting times. Quantitative analysis of 16 cultivars showed a range of $102{\sim}466{\mu}g/100g$ on dry weight basis (which is equivalent to $25{\sim}116.5{\mu}g/100g$ on fresh weight basis). Resveratrol contents in mulberry leaves was higher in autumn than spring, and higher in fully matured leaves than in juvenile leaves. Among the tested samples, 'Kaeryangppong', 'Sugeppong' and 'Cheongilppong' collected in the middle of October showed high resveratrol contents of $838{\mu}g/100g$, $803{\mu}g/100g$, $800{\mu}g/100g$ on dry weight basis, respectively. Especially mulberry leaves dried in the shade showed of $1,030{\mu}g/100g$ on dry weight basis in resveratrol content, this result may contribute to utilization of mulberry leaves.

• Korean Journal of Ecology and Environment
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• v.38 no.1 s.110
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• pp.1-10
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• 2005

Macroinvertebrates from a first order stream at Mt Jumbong, Kangwon-do, was examined for their abundance and biomass. Sampling was done by using a pipe sampler (${\phi}$ 20 cm) for 11occasions (n = 5) at 4${\sim}$6 weeks intervals during November 1997 through October 1998. Water temperature and electronic conductivity of the study stream ranged $0\;{\sim}\;14^{\circ}C$ and 15${\sim}$25 ${\mu}s$/cm, respectively. During the study, 53 insect taxa and 3 non-insect taxa were collected. Annual mean number of individuals (${\pm}$1 SD) was 77741${\pm}$69232${\cdot}$m$^{-2}$ ${\cdot}$yr$^{-1}$, being high in winter (${\pm}$1 SD) (December: 171178${\pm}$130468 $m^{-2}$) and low in summer (${\pm}$ 1 SD) (June: 29872${\pm}$13078 $m^{-2}$). Non-predatory subfamilies of Chironomidae and Nemoura sp. occupied 53.3% and 21.8% of annual abundance. Annual mean biomass was 10g${\cdot}$m$^{-2}$${\cdot}$yr$^{-1}$ in ash free dry weight (AFDW), being high in late winter (February: 16 gAFDW $m^{-2}$.) and low in summer (June: 3 gAFDW $m^{-2}$). Gammarus sp. represented 39.8% of the total biomass and was followed by non-predatory subfamilies of Chironomidae (15.2%) and Hydatohylax sp. (8.5%, Limnephilidae: Trichoptera). Since the non-predatory subfamilies of chironomidae were composed of many species, Nemoura sp. was the most abundant taxon. However, Cammarus sp. was surely the most important taxon to the functional aspects of this first order stream ecosystems.

• Applied Microscopy
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• v.40 no.2
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• pp.89-99
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• 2010

Fibroblasts are the most common cells in connective tissue and are responsible for the synthesis of extracellular matrix components. The fibrosis associated with chronic inflammation and injury may contribute to cholangiocarcinoma pathogenesis, particularly through an increase in extracellular matrix components, which participate in the regulation of bile duct differentiation during development. Mitochondria produce ATP through oxidative metabolism to provide energy to the cell under physiological conditions. Also, mitochondrial dysfunction and oxidative stress have been implicated in cellular senescence and aging. Alternations in mitochondrial structure and function are early events of programmed cell death or apoptosis and mitochondria appear to be a central regulator of apoptosis in most somatic cell. Clonorchis sinensis, one of the most important parasite of the human bile duct in East Asia, arouses epithelial hyperplasia and ductal fibrosis. Isolated fibroblast from the bile ducts of rats infected by C. sinensis showed increase of cytoplasmic process. In addition, decrease of cellular proliferation was observed in fibroblasts which was isolated from normal rat bile duct and then cultured in media containing C. sinensis excretory-secretory product. However, the effects of C. sinensis infection on the mitochondrial enzyme distribution is not clearly reported yet. Therefore, we investigated the structural change of C. sinensis infected bile duct and mitochondrial enzyme distribution of the cultured fibroblast isolated from the C. sinensis infected rat bile duct. As a result, C. sinensis infected SD rat bile ducts showed the features of chronic clonorchiasis, such as ductal connective and epithelial tissue dilatation, or ductal fibrosis. In addition, fibroblast in ductal connective tissue was damaged by physical effect of fibrotic tissue and chemical stimulation. Immunohistochemically detected mitochondrial electron transferase (ATPase, COXII, Porin) was decreased in C. sinensis infected rat bile duct and cultured fibroblast from infected rat bile duct. It can be hypothesized that the reason why number of electron transferase decrease in fibroblast isolated from the rat bile duct infected with C. sinensis is because dysfunction of electron transport system is occurred mitochondrial dysfunction, increase of ROS (reactive oxygen species) and apoptosis after chemical damage on the cell caused by C. sinensis infection. Overall, C. sinensis infection induces fibrotic change of ductal connective tissue, mutation of cellular metabolism in fibroblast and mitochondrial dysfunction. Consequently, ductal fibrosis inhibits fibroblast proliferation and decreases mitochondrial electron transferase on fibroblast cytoplasm. It was assumed that the structure of bile duct could not normalized and ductal fibrosis was maintained for a long period of time according to fibroblast metamorphosis and death induced by mitochondrial dysfunction.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.3
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• pp.211-216
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• 2005

This study was conducted from March 21 to July 10 in 2004 at JeJu to investigate the influences of worm casting organic fertilizer rates (0, 150, 300, 450, 600 kg/10a) on creeping bentgrass sward. The result obtained were summarized as follows; plant height was getting longer as organic fertilizer increased from 0 to 600 kg/10a. But it was no significance from 450 to 600kg/10a. Root length, SPAD reading value, leave and root weight were the same trend with plant height response. Percentage of land cover and density of creeping bentgrass increased as fertilizer rate increased from 0 to 600 kg/10a. But percentage of land cover and density of weed decreased. Number of weed species were decreased as increasing of organic fertilizers. Then ranking of the dominant weeds were Chenopodium album var. cetrorubrum and Digitaria adscendens, Polygonum hydropiper (at 0kg/10a), Portulaca oleracea and Digitaria adscendens, Polygonum hydropiper (at 150kg/10a), Polygonum hydropiper and Poa annua, Digitaria adscendens (at 450 kg/10a), Polygonum hydropipr and Digitaria adscendens, Portulaca oleracea (at 600 kg/10a).

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.3
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• pp.205-210
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• 2005

This study was conducted from March 21 to July 9 in 2004 at JeJu Island to investigate the effect of different particle sizes (0.3-0.5, 0.5-0.8, 0.8-1.0, 1.0-1.5 and 1.5-2.0mm) on creeping bentgrass vegetation. The results obtained were summarized as follows; plant height became shorter as particle size was increased from 0.3-0.5 to 1.5-2.0 n. Root length, Minolta SPAD-502 chlorophyll reading value, leave and root weight were directly proportional plant height response. Degree of land cover and density of creeping bentgrass decreased as the particle size was increased from 0.3-0.5 to 1.5-2.0nm, and degree land cover and density of weed increased. The number of weed species were increased as the sand particle size was increased. Then ranking of the dominant weeds were Portulaca oleracea, Trifolium repens and Cyperus amuricus (at 0.3-0.5 and 0.5-0.8mm particle size), Trifolium repens, Portulaca oleracea and Polygonum hydropiper (at 0.8-1.0mm particle size), Portulaca oleracea, Polygonum hydropiper and Poa annua (at 1.5-2.0mm particle size). Based on the these findings, the optimum sand particle size for growth of creeping bentgrass seems to be about 0.3-0.5m in volcanic ash soils of Jeju island.