• Korean Journal of Pharmacognosy
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• v.22 no.3
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• pp.197-206
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• 1991

The water extract of Gamisamryungbaekchool-San increased the lifespan of mice implanted intraperitoneally with sarcoma 180. Significant depression of lethal toxicity of cis-platin $(45{\mu}M/kg,\;s.c)$ and renal toxicity (indicated by an increase in blood urea nitrogen value and creatinine value) of cis-platin $(35{\mu}M/kg,\;s.c)$ were observed in mice and rats treated with Gamisamryungbaekchool-San. RBC and WBC were significantly decreased in rats treated with cis-platin, and significant depression of hematologic toxicities of cis-platin $(35{\mu}M/kg,\;s.c)$ in rats treated with Gamisamryungbaekchool-San. After all, alleviative effect of the side actions of cis-platin was acknowledged by combined usage of Gamisamryungbaekchool-San and cis-platin.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.97-101
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• 1999

No-till direct seeding cultivation of rice has major advantages such as saving of labor and cost by eliminating tillage, preparation of seed bed and trans-planting procedure compared to the conventional transplanting cultivation. A field experiment was conducted to evaluate the effects of straw treatment and nitrogen levels on the rice growth in no-till direct-seeding cultivation. Rice straw, vetch straw, and the mixture of both of the straws were mulched on the surface of soil before seeding while 4 levels of nitrogen fertilizer, 0, 7, 9, and 11 kkg/10a respectively, were applied at 3 split times, 3-weeks after sowing, 5-weeks after sowing and the panicle initiation stage. Mulching of vetch straw significantly reduced seedling establishment of rice which may be attributed to low oxidation-reduction potential of soil by vetch mulching treatment. Vetch straw increased the concentration of soil ammonium leading to an extension of the greenish leaf to panicle initiation stage. Agronomic nitrogen use efficiency (AD $E_{N}$) in heavy-mixed straw mulching plots was lower than other treatments. Grain yield and AU $E_{N}$ in the vetch treatment were less affected by fertilized N levels. Conclusively, it is suggested that heavy straw mulching was not efficient for rice seedling establishment and nitrogen usage.e.

• Journal of Plant Biology
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• v.30 no.4
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• pp.257-266
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• 1987

Investigation on the ability of nitrogen usage by N2-fixing Nostoc muscorum and cultured tobacco cells when they were associately cultured on nitrogen-free media was carried out. Also, effect of polyamines on the associated cultured condition was carried out. In addition, morphological changes of N. muscorum and cultured tobacco cells in associate culture were observed to detect the possibility of induction of nitrogen fixing ability on cultued plant cells. The activity of nitrogenase increased markedly when N. muscorum was grown exclusively on nitrogen-free media. When N. muscorum was cultured associately with cultured tobacco cells on nitrogen-free media containing polyamines, high activity was detected in 10-4 M spermine treated group. Investigation on the change of polyamine amounts showed two times increase in spermidine and eight times increase in spermine on a associate culture. These effects of associated culture were shown through morphological change such as dense loclization of N. muscorum around the cultured tobacco cells as well as inside the cells. These results indicate the viability of N. muscorum in cultured tobacco cells and possible induction of nitrogen fixation ability by symbiosis.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2008.04a
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• pp.5-13
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• 2008

The aquatic fern Azolla spp. is of value as a bio-fertilizer for wetland paddy, and also can be used as an ideal feed for cattle, pigs and poultry. It is popular and cultivated widely in other countries like China, Vietnam, and the Philippines, but has yet to be taken up in Korea, in a big way. It fixes nitrogen as high as 3-5kg N per day, because it contains nitrogen fixing blue-green algae, Anabaena azollae. Azolla's ability to create a light-proof mat that suppresses other weeds has been used for centuries in rice production. Azolla spp. has also the capacity to take up the heavy metals ($75{\sim}100%$) and may be used as a bioaccumulator. Moreover, Azolla meal as an unconventional feed resource has a potential as a feedstuff for livestock.

• Korean Journal of Plant Resources
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• v.21 no.3
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• pp.230-235
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• 2008

The aquatic fern Azolla spp. is of value as a bio-fertilizer for wetland paddy. It is popular and cultivated widely in other countries like China, Vietnam, and the Philippines, but has yet to be taken up in Korea, in a big way. It fixes nitrogen as high as 3-5kg N per day, because it contains nitrogen fixing blue-green algae, Anabaena azollae. Azolla's ability to create a light-proof mat that suppresses other weeds has been used for centuries in rice production. Azolla spp. has also the capacity to take up the heavy metals such as Mercury and Chromium (75${\sim}$100%) and may be used as a bioaccumulator in the phytoremediation. Azolla meal also can be used as an unconventional feed resource has a potential as a feedstuff for livestock.

• BMB Reports
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• v.56 no.2
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• pp.56-64
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• 2023

Nitrogen (N) is an essential macronutrient required for plant growth and crop production. However, N in soil is usually insufficient for plant growth. Thus, chemical N fertilizer has been extensively used to increase crop production. Due to negative effects of N rich fertilizer on the environment, improving N usage has been a major issue in the field of plant science to achieve sustainable production of crops. For that reason, many efforts have been made to elucidate how plants regulate N uptake and utilization according to their surrounding habitat over the last 30 years. Here, we provide recent advances focusing on regulation of N uptake, allocation of N by N transporting system, and signaling pathway controlling N responses in plants.

• Journal of Soil and Groundwater Environment
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• v.17 no.1
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• pp.22-32
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• 2012

This study suggests a method to grade groundwater quality quantitatively using statistical approaches for evaluating the quality of groundwater in wells included in the Groundwater Quality Monitoring Network (GQMN). The proposed analysis method is applied to GQMN data from 2001 to 2008 for nitrate nitrogen, chloride, trichloroethylene, potential of hydrogen (pH), and electrical conductivity. The analysis results are obtained as groundwater quality grades of the groundwater representing each of the monitoring stations. The degree of groundwater contamination is analysed for water quality parameters, district, and usage. The results show that the degree of groundwater contamination is relatively high by nitrate nitrogen, bacteria and electrical conductivity and at Seoul, Incheon, Gwangju, Gyeonggido and Jeollado. The degree of contamination by nitrate nitrogen and trichloroethylene is especially high when the groundwater is used for agricultural and industrial water, respectively. It is evaluated that potable groudnwater in GQMN is significantly vulnerable to nitrate nitrogen and bacteria contamination.

• Korean Journal of Ecology and Environment
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• v.38 no.4 s.114
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• pp.510-517
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• 2005

The filamentous cyanobacterium Anabaena is capable of both photosynthesis and nitrogen fixation which probably facilitated its incredible adaptation and proliferation in freshwater environments. A small gene, patS, was found to block nitrogen fixing cells from developing which resulted in death of Anabaena in the absence of combined nitrogen sources. We analyzed the DNA sequences in the vicinity of the patS gene by using a codon usage program and detected no codon bias other than the patS open reading frame. Three overlapping cosmids that contain the patS gene were identified, and the presence of other known heterocyst-controlling genes was examined. The patS expression in response to nitrogen starvation was analyzed at the level of transcription and translation by using Northern blot analyses and lacZ-reporter-gene fusion experiments, respectively. The patS expression increased rapidly (within 12 hours) upon the removal of combined nitrogen from the media.

• Applied Biological Chemistry
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• v.27
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• pp.18-28
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• 1984

In order to improve feed values of Korean agricultural by-products, various treatments including physical, chemical, physicochemical and fermentation were suggested in th is review article. Physical treatments such as chopping, grinding and pelleting reduce partiole size of agricultural by-products, and increase passage rate from the rumen, thus may increase voluntary feed intake and weight gain. Digestibility and voluntary feed intake of straw, rice hull and sawdust, also, may be increased by chemical treatment using sodium hydroxide or ammonia. Especially, because nitrogen content of by-products increase and toxic problem is not posed by ammonia treatment, it's practical usage is recommended in Korea. Silage or fermentation treatment using principles of microbial fermentation may improve palatability of low quality by-products. As mentioned above, it is concluded that various treatments suggested are desirable and improve feed value but may raise several problems. Unfortunately, because cost for installation and products is great and processing work is complicate, farmers are not using well these processing methods until now. Therefore, in order to increase the practical usage at farm level, it is thought that many research works be achieved for efficient process which have simple operation and low installation cost.

• Journal of the Semiconductor & Display Technology
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• v.22 no.4
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• pp.72-75
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• 2023

Carbon neutrality has been emerged as important mission for all the manufacturing industry to reduce energy usage and carbon emission equivalent. Korean semiconductor and display manufacturing industries are also in huge interest by minimize the energy usage as well as to find a less global warming product gases in both etch and cleaning. In addition, Korean government is also investing long term research and development plan for the safe environment in various ways. In this paper, we revisit previous research activities on carbon emission equivalent and current research activities performed in semiconductor process diagnosis research center at Myongji University with respect to the reduction of NF3 usage for the PECVD chamber cleaning, and we present the analytical result of the exhaust gas with residual gas analysis in both 6 inches and 12 inches PECVD equipment. The presented result can be a reference study of the development of new substitution gas in near future to compare the cleaning rate of the silicon oxide deposition chamber.