• Korean Journal of Weed Science
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• v.10 no.4
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• pp.328-337
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• 1990

The incividual and combined effects of the chloroacetanilide herbicide pretilachlor and of the safener fenclorim on the growth and selected physiological processes of rice (Oryza sativa L., var 'Lemont')were evaluated under greenhouse and laboratory conditions. Fenclorim applied at rates ranging from 50 to 300 g a.i./ha antagonized the injurious effects caused by 150 to 900 g a.i./ha of pretilachlor on 15-day old wet-sown rice grown under greenhouse conditions. When used rates of 150 g/ha or higher, fenclorim reversed completely the effects of all doses of pretilachlor on rice. When the two compounds were given simultaneously, fenclorim enhanced the uptake of $^{14}C$pretilachlor into rice leaf mesophyll protoplasts measured for 1 hr, indicating that competition for uptake at the protoplast level is not involved in the protective action of this safener. The safener-induced stimulation of pretilachlor uptake was particularly evident when fenclorim was used at concentrations of 10, 20 and $40{\mu}M$. Following 4 hr of incubation, individual treatments with pretilachlor inhibited the in vitro incorporation of radiolabeled precursors into proteins, DNA, and lipids of rice leaf protoplasts only when used at the high concentration of $100{\mu}M$M. Individual treatments with high concentrations (10 or $100{\mu}M$) of the safener fenclorim inhibited the incorporation of radiolabeled precursors into proteins and lipids of rice protoplasts, but had no DNA synthesis. The combined effects of pretilachlor and fenclorim on the incorporation of radiolabeled precursors into these macromolecules of isolated rice mesophyll protoplasts appeared to be additive or slightly synergistic rather than antagonistic. Fenclorim at $1{\mu}M$ antagonized the effects of pretilachlor on total lipids of rice leaf protoplasts. In addition, individual and combined treat-menu with pretilachlor and fenclorim influenced the incoroporation of$^{14}C$acetate into polar lipids, triglycerides and steryl esters of rice leaf protoplas causing a redistribution of carbon in these lipid fractions. However, these effects were not large enough to explain the herbicidal activity of pretilachlor or to account for the protective action of the safener fenclorim. Overall, the uesults of the present study idnicate that the safener fenclorim does not seem to protect rice against pretilachlor injury by antagonizing its effects on protein, DNA, or lipid syntheses.

• Journal of fish pathology
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• v.2 no.1
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• pp.1-18
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• 1989

In Korea, studies on a Nematode, Anguillicola crassa parasitic in the air bladder of eel are not yet reported. This reason led the author to study the parasitic species, state and life history of the A. crassa parasitized in the air bladder of eel in order to take effective control measures against its damage. The size of fully developed eggs was 80 to $92(86.7){\times}62$ to $71(67.4)\;{\mu}m$, larva was 210 to $240(225){\times}18$ to $23(20.6)\;{\mu}m$. The intermediate host of A. crassa was Thermocyclops hyalinus, it was capable for parasitizing the eel after 4 days of invasion and then the size of larva was 360 to $420(390){\times}28$ to $35(31)\;{\mu}m$. Fifty days after eel had ingested the Thermocyclops hyalinus infected with larva of A. crassa, the larvae matured into adult worms in the air bladder of eel. The size of detected adult worms was 7.3 to $31.0(16.5){\times}0.5$ to 2.2(1.2) mm, 4.9 to $13.3(8.3){\times}0.3$ to 0.9(0.4) mm. Investigating the morphology of the worms, they were identified as A. crassa. Monthly the parasitic rate of the worms in the eel was high in June, September and December, but low in January to March. After the investigation on the significance between non-parasitic fish and parasitic fish, it was not significant, therefore it can be considered that there is no effect of infection in the growth of eel. Any abnormality of eels air bladder tissue was not seen by the infection of A. crassa. At 25.0 to $26.7^{\circ}C$ of water temperature the death time of Thermocyclops hyalinus by masoten treatment was 14 hours in 0.5 ppm, 20 hours in 0.4 ppm, 22 hours in 0.3 ppm, 30 hours in 0.2 ppm and 42 hours in 0.1 ppm.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.373-381
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• 2008

To select of optimum rice species and germanium (Ge) application method for production of functional rice with Ge, the growth characteristics, Ge absorption and grain quality of rice plant were investigated under different rice species (Hopyungbyeo, Junambyeo, Ilmeebyeo and Dongjinbyeo) and Ge application method (soil application and foliar spray). The rice yield by soil application was higher in the order of Hopyungbyeo $\fallingdotseq$ Junambyeo > Ilmeebyeo >> Dongjinbyeo. On the other hand, the rice yield by foliar spray was higher in the order of Junambyeo >> Ilmeebyeo > Dongjinbyeo > Hopyungbyeo. The rice yield by soil application was higher than that by foliar spray regardless of rice species. For soil application, the Ge absorption in various parts of the rice was higher in the other of rice bran > brown rice > polished rice regardless of rice species. The Ge absorption of brown rice in Hopyungbyeo, Ilmeebyeo, Dongjinbyeo and Junambyeo by soil application was 14.5, 8.0, 11.6 and $10.4\;mg\;kg^{-1}$, respectively. In leaf, stem and root, the Ge absorption by foliar spray was higher than that by soil application, whereas, in rice bran, brown rice and polished rice, the Ge absorption by soil application was higher than that by foliar spray. The optimum rice species and Ge application method were demonstrated to be Hopyungbyeo and soil application, respectively, which provided suitable conditions for production of functional rice with Ge.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.553-562
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• 2017

In these days, agricultural reservoirs are considered as a useful resource for recreational purposes, tour and cultural amenity for vicinity communities as well as irrigation water supply. However, many of the agricultural reservoirs are showing a eutrophic or hyper-eutrophic state and high level of organic contamination. In particular, about 44.7% of the aged agricultural reservoirs that constructed before 1945 exceed the water quality criteria for irrigational water use. In addition to external loading, internal nutrient loading from bottom sediment may play an important role in the nutrient budget of the aged reservoirs. The objectives of this study were to characterize variations of thermal structure of a shallow M reservoir (mean depth 1.7 m) and examine the potential of internal nutrient loading by continuous monitoring of vertical water temperature and dissolved oxygen (DO) concentration profiles in 2015 and 2016. The effect of internal loading on the total loading of the reservoir was evaluated by mass balance analysis. Results showed that a weak thermal stratification and a strong DO stratification were developed in the shallow M Reservoir. And, dynamic temporal variation in DO was observed at the bottom of the reservoir. Persistent hypoxic conditions (DO concentrations less than 2 mg/L) were established for 87 days and 98 days in 2015 and 2016, respectively, during the no-rainy summer periods. The DO concentrations intermittently increased during several events of atmospheric temperature drop and rainfall. According to the mass balance analysis, the amount of internal $PO_4-P$ loading from sediment to the overlying water were 37.9% and 39.7% of total loading during no-rainy season in 2015 and 2016, respectively on August when algae growth is enhanced with increasing water temperature. Consequently, supply of DO to the lower layer of the reservoir could be effective countermeasure to reduce nutrient release under the condition of persistent DO depletion in the bottom of the reservoir.

• Journal of the Korean Geographical Society
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• v.41 no.2 s.113
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• pp.168-187
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• 2006

Windy meteorological conditions and dried fire fuels due to higher atmospheric instability and dryness in the lower troposphere can exacerbate fire controls and result in more losses of forest resources and residential properties due to enhanced large wildland fires. Long-term (1979-2005) climatology of the Haines Index reconstructed in this study reveals that spatial patterns and intra-annual variability of the atmospheric instability and dryness in the lower troposphere affect the frequency of wildland fire incidences over the Korean Peninsula. Exponential regression models verify that daily high Haines Index and its monthly frequency has statistically significant correlations with the frequency of the wildland fire occurrences during the fire season (December-April) in South Korea. According to the climatic maps of the Haines Index created by the Geographic Information System (GIS) using the Digital Elevation Model (DEM), the lowlands below 500m from the mean sea level in the northwestern regions of the Korean Peninsula demonstrates the high frequency of the Haines Index equal to or greater than five in April and May. The annual frequency of the high Haines Index represents an increasing trend across the Korean Peninsula since the mid-1990s, particularly in Gyeongsangbuk-do and along the eastern coastal areas. The composite of synoptic weather maps at 500hPa for extreme events, in which the high Haines Index lasted for several days consecutively, illustrates that the cold low pressure system developed around the Sea of Okhotsk in the extreme event period enhances the pressure gradient and westerly wind speed over the Korean Peninsula. These results demonstrate the need for further consideration of the spatial-temporal characteristics of vertical atmospheric components, such as atmospheric instability and dryness, in the current Korean fire prediction system.

• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.197-216
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• 2008

Managing a mixture of zoysiagrass with tall fescue has been proposed in transitional zone as a practical practice to combine the advantages of the two species and compensate the limitations. To manage the mixture is a challenge because two species are involved. The objective of this study was to determine if zoysiagrass/tall fescue mixture can be maintained with proper mowing and fertilization under simulated sport traffic at an acceptable quality level. Zoysiagrass was seeded in June and tall fescue was overseeded in August 1996. In November 1996, zoysiagrass coverage was 62.36, 29.88, and 30.02% for 0, 50, and $100\;Kg\;ha^{-l}\;N$ rates, respectively. At the same time, zoysiagrass coverage was 23.53, 41.95, and 57.40% for the mowing heights of 6.5, 5.0, and 3.5 cm, respectively. Zoysiagrass and tall fescue coverage in July 1997 was showing the same trend as in the late season of 1996 although the differences were not as big. There were significant interactions between N fertilization rates and mowing heights. In November 1998, the zoysiagrass coverage was different among the two tall fescue variety mixtures, 21.68, and 32.25% in 'Arid' and 'Grasslands Garland', respectively. Zoysiagrass coverage was favored in lower mowing height, lower N rates, and lower traffic. Interaction effects on zoysiagrass were found between tall fescue variety and nitrogen rate, tall fescue variety and mowing height, and traffic and nitrogen rate. Zoysiagrass shoot density was 7.42, 25.47, and 58.95% for mowing heights of 6.5, 5, and 3.5 cm, respectively; and it was 47.27, 20.27, and 26.26% for N rates of 0, 50, and $100\;Kg\;ha^{-l}\;$, respectively in 1998. The effects on zoysiagrass shoot density from the interaction of N rate and tall fescue variety was significant in 1998. Shoot density responded to the N rate, mowing height, and traffic differently from the ground coverage, indicating that shoot and leaf growth have different adaptation strategies.

• Management & Information Systems Review
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• v.33 no.1
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• pp.191-217
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• 2014

The Purpose of this study is to find the effect factors of R&D investment in SMEs which plays an important role in the national economy, and the differences of the effect factors by the type of SMEs. The subject of this study is about 3,400 SMEs mentioned in "The survey of technical statistics on SMEs in 2007" by Korea Federation of Small and Medium Business. The effect factors are related with the size of business, the infrastructure of R&D and the activities of R&D which have been studied by many researchers. The methods of analysis are regression analysis, moderating effect analysis and the software package used is SPSS 12.0. The results of the study are as fallow. First, it was found that unlike in previous studies which show the effect of the elements of business's size, research infrastructure, research activities on R&D investment, one element alone can't be considered for meaningful result but the various elements have effect on R&D investment at the same time. In other words, the number of employees and the sales as the elements of business's size, the ratio of researchers, the technical ability, the ratio of equipment possession and the intellectual properties as the elements of R&D infrastructure, the activity of ideas and joint research as the elements of R&D activities have positive(+) effect, whereas the participation of CEO in the activity of R&D as the elements of R&D activities activity has negative(-) one. The number of employees, the ratio of researchers, and the sales had relatively high influence whereas equipment possession, technical ability, intellectual properties, the participation of CEO in the research, the activity of idea, joint research had relatively low influence. Next, it was also found that there are differences of the effect factors over the types of SMEs. SMEs were classified into 19 types by eight criteria such as start-ups and existing business by business age; small business and medium business by size; manufacturing business and service business by product type;independent business and subcontractor business by dealing type; businesses in the entering, growing, maturing and restructuring stage by growth stage; businesses with low, medium and high technology by technological level; pioneering business and non-pioneering business by industrial type; and businesses with state-of-the-art technology and non-advanced business by the level of business activities. The meaning of this study lies in the fact that it found the various effect factors should be considered at the same time when conducting study on SMEs' R&D investment, and the differences by the type should be acknowledged. This study surpassed the limitations of the previous studies which focused on a couple of factors and types. This study result can also be considered for other studies on achievement, organization, marketing and others. Moreover, it shows that a differential policy by business type is needed when formulating SME policy.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.9-9
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• 2014

Null mutants generated by targeted gene replacement are frequently used to reveal function of the genes in fungi. However, targeted gene deletions may be difficult to obtain or it may not be applicable, such as in the case of redundant or lethal genes. Constitutive expression system could be an alternative to avoid these difficulties and to provide new platform in fungal functional genomics research. Here we developed a novel platform for functional analysis genes in Magnaporthe oryzae by constitutive expression under a strong promoter. Employing a binary vector (pGOF1), carrying $EF1{\beta}$ promoter, we generated a total of 4,432 transformants by Agrobacterium tumefaciens-mediated transformation. We have analyzed a subset of 54 transformants that have the vector inserted in the promoter region of individual genes, at distances ranging from 44 to 1,479 bp. These transformants showed increased transcript levels of the genes that are found immediately adjacent to the vector, compared to those of wild type. Ten transformants showed higher levels of expression relative to the wild type not only in mycelial stage but also during infection-related development. Two transformants that T-DNA was inserted in the promotor regions of putative lethal genes, MoRPT4 and MoDBP5, showed decreased conidiation and pathogenicity, respectively. We also characterized two transformants that T-DNA was inserted in functionally redundant genes encoding alpha-glucosidase and alpha-mannosidase. These transformants also showed decreased mycelial growth and pathogenicity, implying successful application of this platform in functional analysis of the genes. Our data also demonstrated that comparative phenotypic analysis under over-expression and suppression of gene expression could prove a highly efficient system for functional analysis of the genes. Our over-expressed transformants library would be a valuable resource for functional characterization of the redundant or lethal genes in M. oryzae and this system may be applicable in other fungi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.59-67
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• 1983

An experiment on the rearing of tilapia stocked in closed recirculating tanks eliminating biological filter beds was carried out at the Fish Culture Experiment Station of the National Fisheries University of Pusan, from May 18 through October 21, 1982, and the growth rates, feed conversion, water quality, spawning prevention and space utilization efficiency were discussed. Finally discussed is the feasibility on the establishment of commercial production units. On the water quality, the water temperature ranged from $22.8^{\circ}C\;to\;29.1^{\circ}C$, and total ammonia arround 10 ppm or slightly up. Maintaining phytoplankton bloom was not successful probably because of the active consumption by the heavily stocked tilapia. Several attempts were made by changing the culture water with green water from a nearby earthen pond with results of fading-away in a couple of days. Feed conversions were relatively high ranging from 0.9 to 1.2 except for experiment 1 when the fish were not fully recovered from weakened wintering state. The feed used was partly laboratory prepared $25\%$ protein diet and mostly commercially available $39\%$ protein carp feed. Spawning was completely controlled during the experiment, resulting from density effect, which ranged from 10kg to 40.7kg per square meter with water depth of 0.5 to 0.6m. Space utilization efficiency was very high. Daily net production from the experiment division 3, which showed the highest result, was 6.206 kg per tank, which is calculated 3,235 metric tons per hectare per year, This time, water temperature ranged from 27.8 to $29.1^{circ}C$, average being $28.4^{circ}C$, and total ammonia arround 10 ppm. An estimation for the commercial set-up of the production system based on the results of experiment divisions which had initial stocking rate $15\;kg/m^2$ or up, is made. If the total facility, 8 tanks comprising $56\;m^2$ in surface area, is used for the present study, the yield would become 5,639 kg from 200 day rearing, which would be possible under double sheets vinyl house without additional heating, and it is thought feasible in the economic view point, when 10 or more units are operated.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.13-22
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• 2005

By extracting the sample of Ulmus davidiana Planch(Ulmaceae), which was known to have the protection of damaged organ and the anti-inflammation action, it was experimented whether it is available for the application of treatment of osteoporosis. In the previous experiment, the extracts from Ulmus davidiana Planch(Ulmaceae) were confirmed to inhibit Cathepsin K through treating the cell of long bone, which contains osteoclast. Through this, it is suggested that Ulmus davidiana Planch(Ulmaceae) can play a role of prodrug as an inhibitor of absorbing bone ash in the treatment of osteoporosis. In the present experiment, a research in vitro Ulmus davidiana Planch(Ulmaceae) on the growth and sensibilization of osteoblast in a state that induced osteosis by using the cell tissue of MC3T3-El pre-osteoblastic was conducted. As a result, it could be confirmed that Ulmus davidiana Planch(Ulmaceae) has the strengthening function by enhancing the dosage and the activity of ALP depending on the time. The dosage was observed at the minimum of $50{\mu}g/m{\ell}$ and the maximum of $150{\mu}g/m{\ell}$. The enhancement in bone morphogenetic protein-2 at $100{\mu}g/m{\ell}$ UD could be observed, and it also increased the concentration of ALP mRNA within the cell of MC3T3-El. At $60{\mu}g/m{\ell}$ UD which indicated a little increase in Type I collagen mRNA for a long time of culture. However, it was shown to sharply inhibit the expression of gene in the culture between 15-20 days. These results suggest that Ulmus davidiana Planch(Ulmaceae) has an influence upon bone metabolism through thje sensibilization of osteoblast. Therefore, it could be known that utilized Ulmus davidiana Planch(Ulmaceae) can be positively applied for the general disease of bone metabolism through future studies.