• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.162-169
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• 1998

This study was carried out to assess the roles of soil and vegetation on the nutrient cycling in paddy ecosystem where excessive amounts of animal wastes were flowed in due to the rain. Experimental sites included one abandoned and four cropping paddy fields which were moderately terraced under a small farm village raising 90 milk cows and 35 deer under open-air condition. The watershed covered 4 ha with every 50% of uptown and fodder crops. Concentrations of $NH_4-N$ and $P_2O_5$ in waste water flowed into the abandoned paddy field, enforced by the rain of $56.4mm\;day^{-1}$, were $8.3mg\;{\ell}^{-1}$ and $1.8mg\;{\ell}^{-1}$, respectively. Total mass of rainfall inflow to abandoned field during rice growing period (1 May to 30 Sept.) was $20,900Mg\;ha^{-1}$. Total amounts of $NH_4-N$ and $P_2O_5$ contained in that inflow were estimated as 173 kg and 38 kg, respectively. Concentrations in the outflow water through one abandoned and four rice paddy fields were reduced by 92% for $NH_4-N$ and 95% for $P_2O_5$, as compared to those in the inflows. The reserved portions of nutrients in the abandoned paddy field ecosystem, which were the summation of the uptake by weed and residues in soil, were 29% of the inflow amount for $NH_4-N$ and 30% for $P_2O_5$. These results demonstrated that soil and vegetation in paddy field ecosystem reduced the excessive nutrients from the animal waste inflow to the extents that might be suitable not only for the better growth of rice plant, located at the lower paddy fields, but also for preservation of the downstream from eutrophication.

• Journal of Life Science
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• v.28 no.9
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• pp.1030-1041
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• 2018

Abiotic stresses limit the growth and productivity of plants. Cellular adaptation to abiotic stresses requires coordinated regulation in gene expression directed by complex mechanisms. This study used the activation tagging system to identify novel salt stress-responsive genes. The study selected 9 activation tagging lines that showed salt stress-tolerant phenotypes during their germination stages. Thermal asymmetric interlaced-PCR (TAIL-PCR) was used to identify the T-DNA tagging sites on the Arabidopsis genome in selected activation tagging lines, including AT7508, AT7512, AT7527, AT7544, AT7548, and AT7556. RT-PCR analysis showed that ClpC2/HSP93-III (At3g48870), plant thionin family (At2g20605), anti-muellerian hormone type-2 receptor (At3g50685), vacuolar iron transporter family protein (At4g27870), and microtubule-associated protein (At5g16730) were activated in AT7508, AT7512, AT7527, AT7544, and AT7556, respectively. Interestingly, in AT7548, both the genes adjacent to the T-DNA insertion site were activated: Arabinogalactan protein 13 (AGP13) (At4g26320) and F-box/RNI-like/FBD-like domains-containing protein (At4g26340). All of the seven genes were newly identified as salt stress-responsive genes from this study. Among them, the expression of ClpC2/HSP93-III, AGP13, F-box/RNI-like/FBD-like domains-containing protein gene, and microtubule-associated protein gene were increased under salt-stress condition. In addition, AT7508, AT7527, and AT7544 were more tolerant to salt stress than wild type at seedling development stage, functionally validating the screening results of the activation tagging lines. Taken together, our results demonstrate that the activation tagging system is useful for identifying novel stress-responsive genes.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.2
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• pp.84-90
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• 2018

Cultivation of high-quality forage crop by using fallow field during winter is required for national high feed self-sufficiency and establishment of self-supply system of high-quality forage crop. Field experiments for cultivation of high-quality winter forage crop were conducted at the paddy and upland fields in Cheonan and Anseong city with treatments of single Italian ryegrass(IRG) and IRG mixed with forage barley at the paddy field and of single forage barley and forage barley mixed with IRG at the upland field in the Mid-west plain. Several cultivation conditions such as broadcasting IRG seed under standing rice, sowing time, tillage method, drainage condition, mixed sowing with forage barley were compared to know the change of growth, yield and quality of winter forage crop. In particular, over-wintering rate and dry matter yield were decreased significantly in late-sown IRG and moisture-stressed forage barley. Yield and quality of forage crops were increased by sowing after tillage, mixed sowing of IRG with barley at the paddy field with good drainage. High yield as much as dry matter $10MT\;ha^{-1}$ with high feed value could be obtained by early sowing of feed barley mixed with IRG at the upland field. Cultivation conditions such as early sowing, sowing after tillage, drainage management are required for higher dry matter yield, quality and stable cultivation of winter forage crops in the mid-west plain of Korea.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.81-86
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• 2001

Prupose : To evaluate the role of linac based radiosurgery (RS) in the treatment of meningiomas, we retrospectively analyzed the results of clinical and follow up CT/MRI studies. Methods and Materials : From the 1988 July to 1998 April, twenty patients of meningioma had been treated with 6 MV linear accelerator based radiosurgery. Of the 20 patients, four $(20\%)$ were male and 16 $(80\%)$ were female. Mean age was 51 years old ($22\~78$ years old). Majority of intracranial location of tumor for RS were parasagittal and sphenoid wing area. RS was done for primary treatment in 6 $(30\%)$, postoperative residual lesions in 11 $(55\%)$ and regrowth after surgery in 3 $(15\%)$. Mean tumor volume was $5.72\;cm^3\;(0.78\~15.1\;cm^3)$ and secondary collimator size was 2.04 cm $(1\~3\;cm)$. The periphery of tumor margin was prescribed with the mean dose of 19.6 Gy $(9\~30\;Gy)$ which was $40\~90\%$ of the tumor center dose. The follow up duration ranged from 2.5 to 109 months (median 53 months). Annual CT/MRI scan was checked. Results : By the follow up imaging studies, the tumor volume was reduced in 5 cases $(25\%)$, arrested growth in 14 cases $(70\%)$, and increased size in 1 case $(15\%)$. Among these responsive and stable 19 patients by imaging studies, there showed loss of contrast enhancement after CT/MRI in four patients. In clinical response, nine $(45\%)$ patients were considered improved condition, 10 $(50\%)$ patients were stable and one $(5\%)$ was worsened to be operated. This partly resulted in necrosis after surgery. Conclusion : The overall control rate of meningiomas with linac based RS was $95\%$ by both imaging follow-up and clinical evaluation. With this results, linac based RS is considered safe and effective treatment method for meningioma.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.113-120
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• 2008

The influence of incubation temperature, pH and media components on bacteriocin production by Lactobacillus plantarum K11 were investigated. The highest activity was observed in MRS broth, but no bacteriocin activity was obtained in TSB. The bacteriocin was produced from the exponential growth phase and its activity also reached a maximum in MRS broth, but then dropped after 16 hr because of degradation by extracellular proteolytic enzymes or exhaustion of medium nutrients. The optimal temperature and pH for production of bacteriocin were $37^{\circ}C$ and pH 7.0 in MRS broth, respectively. The addition of 0.5 or 1.0% glucose and $0.5{\sim}1.5%$ lactose to MRS resulted in the increase of the bacteriocin production. With 0.5% NaCl and $K_2HPO_4$, the activities were significantly higher than that of control, respectively. However, increasing nitrogen sources such as beef extract, casein, and tryptone and salts such as $NH_4PO_4$, $MgSO_47H_2O$, and $MnSO_4H_2O$, had detected a negative influence upon the bacteriocin production. Consequently, because the bacteriocin produced by L. plantarum K11 was affected by various incubation conditions, the bacteriocin activity of L. plantarum K11 applied in food as a novel starter will be dependent on environmental factors such as fermentation conditions and food ingredients.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.429-433
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• 2003

trans-Resveratrol(3,5,4'-trihydroxystilbene) is phenolic compound present in grapes, wines, and peanuts, has been reported to have health benefits including anticarcinogenic effects, protection against cardiovascular diseases and reduced cancer risk. A simple method for the quantitative extraction of trans-resveratrol from peanut has been developed. Optimal conditions for extraction were investigated. Type of solvent, time, and temperature assayed influenced trans-resveratrol yield. Adequate extraction condition was decided to ethanol/water (80:20v/v) maintained at $25^{\circ}C$ for 45 min. After extraction, the protocol consists of sample preparation using a $\textrm{C}_{18}$ solid-phase extraction (SPE) cartridge after concentrate with rotary evaporator and quantified by reversed phase HPLC using a $\textrm{C}_{18}$ column at 308 nm. Analytical methods for measuring trans-resveratrol in peanut were adapted to isolate, identify, and quantify trans-resveratrol in 11 peanut varieties by HPLC (high-performance liquid chromatography) with UV detector, The 11 peanut varieties content ranged from 0.018 to 1.125 $\mu\textrm{g}/\textrm{g}$ with an average of 0.289 $\mu\textrm{g}/\textrm{g}$. The contents were higher in the seeds with than without testa, regardless of varieties. The trans-resveratrol content was Higher in 110, 130 days after sowing than that of other period.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.215-220
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• 2008

Rahnella aquatilis AY2000 has an unique characteristic which produces an anti-yeast substance (AYS). The AYS of the strain AY2000 was always secreted on agar plate, however, its activity in liquid culture was labile upon storage of the medium. In this paper, cultural conditions of the strain AY2000 for the AYS production were investigated in liquid culture, and minimal inhibitory concentration (MIC) against Saccharomyces cerevisiae was determined for the AYS activity. MIC of the AYS cultured in PYG broth at $^25{\circ}C$ for 24 hr was $23.5{\mu}g/mL$, however, that in MYCS (pH 5.5) broth at the same condition was $15.5{\mu}g/mL$. The activity of the AYS had increased rather in MYCS broth excluded $NH_4$-citrate than in the same broth contained $NH_4$-citrate, and MIC of the AYS produced in MYCS broth without $NH_4$-citrate was $15.5{\mu}g/mL$. When the strain AY2000 was maintained in MYCS broth without $NH_4$-citrate but added $100{\mu}M$ $FeCl_3$, the activity of the AYS had increased and its MIC was $7.8{\mu}g/mL$. MIC of the AYS was $7.8{\mu}g/mL$ after the strain AY2000 was cultured in MYCS broth containing $100{\mu}M$ $FeCl_3$ without $NH_4$-citrate, however, its MIC was $31.3{\mu}g/mL$ after 48-60 hr culture in the same broth.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.537-544
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• 1998

The cultivation conditions of transformant Alcaligenes eutrophus AER5 harboring cloned phbC gene for mass production of poly (3-hydroxybutyrate-3-hydroxyvalerate)[P(3HB-3HV)] containing high molar fraction of 3-hydroxyvalerate (3-HV) were investigated. In two-stage batch cultivation, transformant accumulated P(3HB-3HV) containing 52.2 mol% of 3HV compared to 30 mol% of parent strain A. eutrophus H16. The increased 3-HV molar fraction was due to the amplified activity of PHB synthase participating in condensation of 3-HB and 3-HV. To increase efficiency of P(3HB-3HV) accumulation, fructose was added along with precursor compound valerate, and total cell mass and P(3HB-3HV) concentrations remarkably increased, but not 3-HV molar fraction. The effect of magnesium ion showed that P(3HB-3HV) concentration and 3-HV molar fraction were significantly increased upto 6.1 g/L and 71.3 mol% at 0.01 g/L of MgSO$_4$, respectively. The efficiency of several pH adjuster, NaOH, NaOH and (NH$_4$)$_2$SO$_4$, and NH$_4$OH, on total cell mass, p(3HB-3HV) concentration, and 3-HV molar fraction was also compared. To overcome the disadvantage of two-stage cultivation, one-stage intermittent fed-batch cultivation was attempted, such a way 10.0 g/L of fructose was supplied for cell growth at initial 36 hr and then 10.0 g/L of valerate and 5.0 g/L of fructose were applied to induce the accumulation of P(3HB-3HV), consequently, 10.4 g/L of P(3HB-3HV) with 38 mol% of 3-HV fraction could be obtained after 72 hr. These results can be used for elucidating cultivation strategy for mass production of P(3HB-3HV) containing high 3-HV molar fraction using transformant A. eutrophus AER5 harboring cloned phbC gene.

• Applied Biological Chemistry
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• v.48 no.2
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• pp.132-139
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• 2005

The major obstacle in the popularization of Chungkookjang is the short shelf-life of $2{\sim}3$ months and some problems concerning storage including the growth of molds even in the products even within shelf-life. To solve these problems we conducted a research to improve its storage by using the vacuumed packaging and sanitary method through seed culture, innoculation and sterilization. For the optimization of storage time, temperature and sterilization temperature, we measured viable cell numbers of bacteria and fungi, amount of gas outbreak and contents of amino type nitrogen and monitored these experimental results by response surface methodology of SAS program, so that we could observe the quality changes of Chungkookjang during shelf-life. Especially fungi, which are the biggest troublemaker in Chungkookjang shelf-life, couldn't be detected from the generally and vacuum-packed samples; also, viable cell numbers were highly influenced by sterilization temperature and in vacuum-packed samples. In the case of vacuum-packed samples, amount of gas outbreak was highly influenced by sterilization temperature of its storage conditions and it was higher in generally packed samples as compared to vacuum-packed samples even at any storage conditions. The changes of pH in generally and vacuum-packed samples were highly influenced by the storage temperature. As the temperatures of storage and sterilization were higher and the storage time was longer, so the amount of gas outbreak was accordingly lower. These results showed that amino type nitrogen contents in generally and vacuum-packed samples were systematically influenced by the temperature, storage time and sterilization temperature. Also the result showed that the change of amino type nitrogen contents during storage was less in vacuum-packed samples than in general ones. Based on the above results, we can produce Chungkookjang products with extended shelf-life of as far as 6 months without any quality change using sanitary manufacturing method, vacuumed packaging condition, sterilization in $70^{\circ}C$ for 60 minutes and storage under $10^{\circ}C$ during shelf-life. According to this research, we have the possibility to greatly increase the goods value of Chungkookjang by developing the manufacture processing and packaging.

• International Commerce and Information Review
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• v.14 no.3
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• pp.3-30
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• 2012

In the development process, small and medium-sized enterprises in China have shown their unique features and regularities which are closely related to China's national condition and economic characteristics. But in 2008, because of the global financial crisis which started in the USA, the rate of Chinese export and the rate of economic growth has evidently slowed. Due to shortage of funds, foreign orders fell, increase the value of RMB, lack of talented factors, Chinese SMEs are facing bankruptcy. In this context, the purpose of this study is to examine the effects of domestic and international market environment, the government assistance for entering overseas market, entrepreneur characteristics, etc. on the global performance. Based on these, a research model and some hypotheses were set up and tested by the multiple regression analysis with total 317 effective survey data. The results of this paper are as follows. First, a positive effect relation on the financial performance was shown for the companies with high domestic and international market environment in the aspect of market environment. According to such analysis result, it was found that the market environment in which SMEs belong to is a very important factor. Second, in the aspect of government export assistance related to overseas, market development showed a positive effect relation on the both financial and non-financial performance. However, the direct financial assistance showed a positive effect relation only on the non-financial performance. Overall, it was found that the government assistance program on entering overseas market is having significant effects on SMEs, but direct financial assistance have not achieved the desired results. Third, the innovative-ness and progressiveness of entrepreneur showed a positive effect relation on the global market performance. However, the risk-taking of entrepreneur only showed a negative effect relation on the non-financial performance. Overall, it was found that the entrepreneurship of SMEs is an important and influential factor. This is a result implying that the propensity of taking too much risk is not desirable based on the uncertainty of the global environment market. To sum up, this study confirmed that the market environment, the government assistance and entrepreneur characteristics, which are the major prerequisites of global performance, have effects on global performance.