• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.105-110
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• 2008

The main purpose of this work is the development of water quality level model using the data such as DO, EC, BOD, $COD_{Cr},\;NH_3-N,\;NO_3-N,\;PO_4-P$, T-N, T-P, and SS in 88 agricultural streams of the Han river watersheds. To grant water quality level for each parameters, it divided into 20% respectively in the order of water quality level. On the basis of the lowest water quality level, water quality of streams was assigned. As the result, number of stream corresponding to Level Ⅰ was 0, Level II was 1 stream, Level III was 3 streams, Level IV was 22 streams, and Level V was 62 streams. By standardized canonical discriminant function coefficient, $NO_3-N$ was the highest in 0.427 at the discriminant power. According to discriminant function for water quality level, it was equal to $-4.648+3.246{\times}[NO_3-N],\;-5.084+3.456{\times}[NO_3-N],\;-4.298+3.067{\times}[NO_3-N],\;and\;-7.369+4.396{\times}[NO_3-N]$ from Level II to Level V, respectively. As a result of test at real data of the Han river watersheds in 2007, the suitability of water quality level model was high to 88.4%.

• Journal of Mushroom
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• v.14 no.2
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• pp.59-63
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• 2016

A new commercial strain of oyster mushroom (was developed by hyphal anastomosis, and was improved byhybridization between a monokaryotic strain derived from Pleurotus ostreatus ASI 0635 (Gonji 7ho) and a dikaryotic strain derived from P. ostreatus ASI 0666 (Mongdol). The optimum temperatures for mycelial growth and fruiting body development were $25{\sim}30^{\circ}C$ and $12{\sim}18^{\circ}C$, respectively. When PDA (potato dextrose agar medium) and MCM (mushroom complete medium) were compared, mycelial growth was faster in MCM. Similar results were observed with the control strain P. ostreatus ASI 2504 (Suhan 1ho). Analysis of the genetic characteristics of the new cultivar ('Gosol') showed a different DNA profile from that of the control ASI 2504 strain, when RAPD (raurpDNA) primers URP1, 2, 3, and 7 were used. Fruiting body production per bottle was approximately116 g based on a production performance test. In addition, yields from a farm field trial were stably achieved in an inadequate production enviro. The color of the pileus was blackish gray, and the stipe was long and thick. Therefore, we expect that this new strain will satisfy consumer demand for high quality mushrooms.

• The Korean Journal of Pharmacology
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• v.31 no.1 s.57
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• pp.1-9
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• 1995

The slow development of histopathological changes and long period required for stabilization of lesions have suggested that secondary injury processes exacerbate the effect of initial mechanical insult after traumatic spinal cord injury (SCI). The importance of glutamate receptors in the normal functions of spinal cord, in concert with the large body of evidence that points to their involvement in neurotoxicity due to both ischemic and traumatic insults to the CNS, suggested a probable role of glutamate receptors in secondary injury process after traumatic SCI. In order to investigate the involvement of excitatory amino acid in the secondary injury process after SCI, this study examined the effect of dextrorphan, a noncompetitive NMDA receptor antagonist, on the recovery of hindlimb function and the residual tissue at injury site following SCI. Locomotor function was assessed using open field test (21 point scale). At 8 weeks spinal cord tissue was examined using quantitative histopathologic technique. Prior to surgery female Long-Evans rats were adapted to the test environment. Rats received laminectomies (T9/T10), and spinal cord contusions (NYU impactor) were produced by a 10 gm weight dropped 25 mm. DXT (15 or 30 mg/kg, i.p.) or saline was injected 15 min before contusion. Behavioral testing resumed 2 days post-injury and continued twice a week for 8 weeks. No differences between DXT and saline groups were found for hindlimb function and sparing tissue at the lesion site. These results suggest that NMDA receptor might not be involved in secondary injury processes after traumatic SCI.

• Journal of Bio-Environment Control
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• v.20 no.3
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• pp.189-196
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• 2011

The objective of this study was to investigate the effects of light intensity and electrical conductivity (EC) of nutrient solution during short day treatment in an ebb and flow systems on the growth and nutrient uptake of potted Kalanchoe blossfeldiana 'Rako' and the nutrient accumulation of growing medium. Nutrient concentrations in the growing medium were also analyzed to investigate the accumulation rates of macro-nutrients such as T-N, P, K, Ca, and Mg, respectively. To achieve the objectives, plants were fed with a nutrient solution with 1.2, 1.8, or $2.4dS{\cdot}m^{-1}$ under three daily photosynthetic photon flux (PPF) of 4.26, 5.51, or $9.75mol{\cdot}m^{-2}{\cdot}d^{-1}$. Both light intensity and EC of nutrient solution significantly influenced the crop growth. The elevation of PPFs resulted in the increase of plant growth. For each light condition, plant growth, such as dry and fresh weight and leaf area, was the highest when the electrical conductivity of nutrient solution was controlled to $2.4dS{\cdot}m^{-1}$. However, growth was acceptable in the EC ranges from 1.8 to $2.4dS{\cdot}m^{-1}$. Both light intensity and EC of nutrient solution significantly influenced the uptake of nutrients in the solution tanks and the accumulation of nutrients in the growing medium. As the EC of nutrient solution was elevated, the absorption rates of $NO_3^-$, $PO_4^{-3}$, $K^+$, and $Mg^{2+}$ by crops and accumulation of those in growing medium increased, but the light intensity did not significantly influence the absorption rates. Based on the above results, the regression models were suggested for anticipating the macro-nutrient accumulations in growing medium.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.14-18
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• 2004

Analysis methods of artificial sweeteners, aspartame, acesulfame potassium, sodium saccharin, and sucralose isolated from foods were developed using high performance liquid chromatography, HPLC conditions for aspartame, acesulfame potassium, and sodium saccharin were: column, Symmetry $C_{18}(3.9mm\;i.d{\times}150mm,\;5{\mu}m)$; mobile phase, 0.05M sodium phosphate monobasic : acetonitrile (9 : 1, pH 3.5, containing 0.01M tetrapropylammonium hydroxide); detector, UV detector at 210 nm. HPLC condition for sucralose were : column, Symmetry $C_{18}(3.9mm\;i.d{\times}150mm,\;5{\mu}m)$; mobile phase, water:methanol (7 : 3); detector, refractive index detection (sensitivity = 16). Recoveries of artificial sweeteners in foods including soft drinks, fruit and vegetable beverages, alcoholic beverages, fermented milk beverages, soybean milk, ice cream, snacks, chewing gums, jam, honey, kimchi salted food, special dietary products, processed fish products, candies, food additive mixtures, chocolate and cocoa were 76.1-101.3%, 82.3-103.2%, 83.1-103.7%, and 80,6-99.5% for aspartame, acesulfame potassium, sodium saccharin, and sucralose, respectively.

• Journal of Mushroom
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• v.13 no.3
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• pp.212-216
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• 2015

A new commercial strain "Mongdol" of oyster mushroom was developed by hyphal anastomosis. It was improved with hybridization between monokaryotic strain derived from Pleurotus ostreatus ASI 0627 and dikaryotic strain derived from P. ostreatus ASI 2929. The optimum temperature of mycelial growth and fruiting body development were $25{\sim}30^{\circ}C$ and $12{\sim}18^{\circ}C$, respectively. When two different media including PDA (potato dextrose agar medium) and MCM (mushroom complete medium) were compared, the mycelial growth of this mushroom was faster in MCM than in PDA. Similar result was observed with the control strain P. ostreatus ASI 2504. Analysis of the genetic characteristics of the new cultivar "Mongdol" showed a different DNA profile as that of the control strain ASI 2504, when RAPD (Random Amplified Polymorphic DNA) primer URP3 and URP6 were used. Fruiting body production per bottle was about 106 g using demonstration farms. The color of pileus was blackish gray and the stipe was long. Therefore, we expect that this new strain "Mongdol" will satisfy the consumer's demand for high quality mushrooms.

• Journal of Chest Surgery
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• v.37 no.1
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• pp.1-10
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• 2004

Background: Currently, the cardiopulmonary machine with non-pulsatile pumps, which are low in internal circuit pressure and cause little damage to blood cells, is widely used. However, a great number of experimental studies shows that pulsatile perfusions are more useful than non-pulsatile counterparts in many areas, such as homodynamic, metabolism, organ functions, and micro-circulation. Yet, many concerns relating to pulsatile cardiopulmonary machines, such as high internal circuit pressure and blood cell damage, have long hindered the development of pulsatile cardiopulmonary machines. Against this backdrop, this study focuses on the safety and effectiveness of the pulsatile cardiopulmonary machines developed by a domestic research lab. Material and Method: The dual-pulsatile cardiopulmonary bypass experiment with total extracorporeal circulation was conducted on six calves, Extracorporeal circulation was provided between superior/inferior vena cava and aorta. The membrane oxygenator, which was placed between the left and right pumps, was used for blood oxygenation. Circulation took four hours. Arterial blood gas analysis and blood tests were also conducted. Plasma hemoglobin levels were calculated, while pulse pressure and internal circuit pressure were carefully observed. Measurement was taken five times; once before the operation of the cardiopulmonary bypass, and after its operation it was taken every hour for four hours. Result: Through the arterial blood gas analysis, PCO2 and pH remained within normal levels. PO2 in arterial blood showed enough oxygenation of over 100 mmHg. The level of plasma hemoglobin, which had total cardiopulmonary circulation, steadily increased to 15.87 $\pm$ 5.63 after four hours passed, but remained below 20 mg/㎗. There was no obvious abnormal findings in blood test. Systolic blood pressure which was at 97.5$\pm$5.7 mmHg during the pre-circulation contraction period, was maintained over 100 mmHg as time passed. Moreover, diastolic blood pressure was 72.2 $\pm$ 7.7 mmHg during the expansion period and well kept at the appropriate level with time passing by. Average blood pressure which was 83$\pm$9.2 mmHg before circulation, increased as time passed, while pump flow was maintained over 3.3 L/min. Blood pressure fluctuation during total extracorporeal circulation showed a similar level of arterial blood pressure of pre-circulation heart. Conclusion: In the experiment mentioned above, pulsatile cardiopulmonary machines using the doual-pulsatile structure provided effective pulsatile blood flow with little damage in blood cells, showing excellence in the aspects of hematology and hemodynamic. Therefore, it is expected that the pulsatile cardiopulmonary machine, if it becomes a standard cardiopulmonary machine in all heart operations, will provide stable blood flow to end-organs.

• Applied Biological Chemistry
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• v.14 no.1
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• pp.9-18
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• 1971

In order to obtain basic information on the production of single cell protein from petroleum, more than 400 yeast strains were isolated from various soil samples in Korea utilizing petroleum hydrocarbon as the sole carbon source. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimal culture condition was searched in the flasks shaken throughout the procedure. And the growing characteristics for the selected yeast strain and chemical analysis of the yeast cell component were carried out. The results obtained were as follows: 1. The selected yeast strain was identified as Candida curvata and we named it Candida curvata-SNU 70. 2. The composition of the medium proposed for the present yeast strain is: Light Gas Oil 30ml, Urea 400mg, Ammonium sulfate 100mg, Potasium phosphate (monobasic) 670mg, Sodium phosphate (dibasic) 330mg, Magnesium sulfate 500mg, Calcium carbonate 3g, Yeast extract 50mg, Tween 20 0.05ml, Tap water 1,000ml. 3. Other culture conditions employed for the yeast were pH 5.5-7.0, temp. $30^{\circ}C$ under an affluent aerobic state. 4. Addition of light gas oil in portions to the culture media as the growth proceeded was more effective, especially in the cultivation on the higher oil concentration media. 5. Studies on the propagation of the yeast cells in the light gas oil medium revealed that the yeast has the lag phase lasted 16 hours and the logarithmic growth phase covered 16 to 28 hours. The specific growth rate was about $0.22\;hr^{-1}$ and doubling time was 3.2 hrs. during the logarithmic growth phase. 6. Under the cultural condition employed, the cell yield against the amount of light gas oil (wt%) was 16.1% and the protein content of the dried yeast cells was 48.4%.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.106-113
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• 2005

This study was carried out to develop a novel hydroponic medium far fruit vegetable crops by using waste synthetic fibers. In physical analysis of the synthetic fiber medium (SFM), the bulk density and percent solid phase were lower, while the porosity and water content were greater in comparison with the rockwool slab. The SFM had pH of 6.5 and EC of $0.03dS{\cdot}m^{-1}$ both of which are similar to those of the rockwool slab. The CEC of 0.39me/100mL of the SFM was lower than compared with 3.29me/100mL of the rockwool slab. However, concentrations K, Ca, Mg and Na were slightly higher in the SFM than those in the rockwool slab. The 'Momotaro' tomato crop in the SFM gave comparable plant height, stem diameter, days to first flowering, fruit weight and percent marketable yield as the rockwool slab. In the SFM and in the rockwool slab, mean fiuit weight were 182g and 181g, percent marketable yield were $93.8\%$ and $92.0\%$, respectively. The marketable yield per 10a in the SFM was 12,799 kg, which was $97\%$ of that in the rockwool slab. Growth parameters such as leaf length and width, leaf number, stem diameter and chlorophyll content of an exportable cucumber crop grown in the SFM and the rockwool slab were not different. Fruit weight was greater in the rockwool slab, while percent marketable yield was greater in the SFM. The marketable fruit yield per 10a of 5,062kg in the SFM was $2\%$ greater than that in the rockwool slab. $NO_3$ concentration in nutrient solution during the crop cultivation was higher in the SFM than in the rockwool slab, while concentrations $NH_4$, K, Ca, Mg and $SO_4$ were not different between the two media.

• Applied Biological Chemistry
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• v.16 no.1
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• pp.1-11
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• 1973

In order to obtain the basic informations on the production of single cell protein from ethanol, 145 yeast strains utilizing ethanol as a sole carbon source were isolated from 32 soil samples in Korea. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimum culture condition, utilization of other carbon sources and the cultural characteristics for the selected yeast, and the chemical analysis of the yeast cell composition, and utilization of ethanol by the selected yeast were investigated. All the culture was carried out in the shaking flasks. The results obtained were as follows: 1. The selected yeast strain was identified as Debaryomyces nicotianae-SNU 72. 2. The optimum composition of the medium for the selected yeast is : Ethanol 40 ml, Urea 0.5 g, Potassium phosphate (dibasic) 0.5 g, Ammoium phosphate (monobasic) 0.15 g, Magnesium sulfate 0.05 g, Calcium chloride 0.01g, Yeast extract 0.005 g, Tap water 1000 ml. 3. The optimum pH was 5.0-5.5, the optimum temperature $30-33^{\circ}C$ and the aerobic state was unimportant. 4. Utilization of methanol, n-propanol, iso-propanol, n-butanol, iso-butanol, tert-amyl alcohol and acetic acid by the selected yeast was very weak. So substitution of the subtrate was thought to be impossible. 5. Studies on the propagation of the yeast cells showed that the lag phase of the yeast cells lasted 16 hours, and the logarithmic growth phase extended 16 to 28 hours. The specific growth rate was about $0.19\;hr^{-1}$ and the doubling time was 3.6 hours during the logarithmic growth phase. 6. As the result of the chemical analysis of the dry yeast cells, the content rate of the crude protein was 55.19 %, the content of others was similar to the average content of the yeast component. 7. After 34 hours cultivation, under the optimum culture condition investigated, the dry cell yield against the amount of the added ethanol was 53.4 % (W/V%), the dry cell yield against the amount of the utilized ethanol was 73.6 % (W/V%), the evaporation rate of ethanol was about 19.1 %.