• Journal of radiological science and technology
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• v.15 no.1
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• pp.65-78
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• 1992

Routine chest radiography is generally imaged by high voltage technique but some radiological technologists use low voltage for imaging. High voltage is usually said between $120\;kV{\sim}140\;kV$. Some RTs like using heavy filtration but others seldom like using it. However which is better for use calcium tungustate film screen system or ortho system and high contrast film or wide latitude c-type film for the exculusive use of chest radiography. We could not make a decision which is ideal method for use. In my opinion any method is not always exellent for chest radiography. In my experiments that I had at Kaken hospital in Japan last year I expect to keep the balance between image quality and diagnostic range and to reduce radiation dose for patients. My experiments are as follows. 1. We have looked into system characteristics(speed and contrast) in accordance with kVp($80{\sim}140$) and added filter($no{\sim}1/16\;VL$) in three screen film systems(BX3+CRONEX4, SRO750+MGH, SRO750+MGL). 2. We have looked into skin dose and film dose with same D=1.8 lung field density in accordance with kVp($80{\sim}140$) and added filter($no{\sim}1/16\;VL$) in three screen film systems. 3. We have compared with the evaluation between correlation of physical image quality(MTF) and optical diagnostic capability. Result are follows. 1. Speed of BX3+CRONEX4 became higher in accodance with kVp and thickness of filter but speed of ortho system was not as like regular system. Thicker filter diminished the speed over 100 kV range in SRO750+MGL. In case of SRO750+MGH speed of 1/16VL filter was looked into lower than speed of 1/4VL filter. Sensitivity of ortho system depends on tube voltage and added filter. 2. Skin dose has been detected $225\;{\mu}Gy{\sim}66\;{\mu}Gy$ in BX3+CRONEX4 from 80 kV, no filter to 140 kV, 1/16VL filter. SRO750+MGH could reduce the patient dose $1/2{\sim}1/3$ level in comparison to that of BX3+CRONEX4. 3. The higher kV was the worse MTF became the thicker filter was the worse MTF became too. MTF of BX3+CRONEX4 was detected better than MTF of SRO750+MGH but SRO750+MGH's optical detectability of small lesion in lung field came out better than that of BX3+CRONEX4. Conclusion Recently routine chest radiography is generally imaged by high voltage but it seems to be there are some questions in using of film screen combination. In high voltage chest radiography the subject contrast will come down that means latitude become wider. In this case if we select the low contrast film screen system(C or L type) the film contrast will fall down extremly and detectability of small lesion will be deteriorated. Wide latitude C, L type film has a merit of high detectability on mediastinum. Furthermore high contrast film screen system has the advantage to keep the high contrast in low density region as like mediastinum and heart shadow. Therefore in low subject contrast high voltage chest radiography we would rather choose the high contrast film screen system(H type) I think. From a view point of patient dose detectability of mediastinum and lung field. The optimum technical facter was found out 120 kV, 1/16VL filter : BX3+CRONEX4, 140 kV, 1/4VL filter : SRO750+MGH, 100 kV, 1/4VL filter : SRO750+MGL.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.120-130
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• 1996

Crisphead lettuce(Lactuca sativa L.) was grown in NFT to investigate the effects of NO$_3$-N and NH$_4$-N ratio in nutrient solution and elevated $CO_2$ treatment in the crisphead lettuce growth. This experiment has been conducted under three different ratios of NO$_3$-N:NH$_4$-N(100:0, 75:25, 50:50) with two $CO_2$ concentration (control, 1500ppm ). The results are as follows; 1. In the case of not controlling pH and EC in nutrient solution, pH was gradually increased in NO$_3$-N:NH$_4$-N=100:0 treatment but rapidly decreased in the nutrient solution 2. Daily changes of NO$_3$-N and NH$_4$-N were observed without controlling the nutrient solution. In the treatments of NO$_3$-N:NH$_4$-N ratios were 75:25 and 50:50, NO$_3$-N absorption rates were 27.7% and 26.1%, while NH$_4$-N absorption rates were 87.9% and 71.2%, respectively. 3. There was little differences in total nitrogen of leaves. However phosphorus, potassium, calcium and magnesium contents were highly shown in the treatment of $CO_2$ 1500ppm and 100:0 ratio of NO$_3$-N:NH$_4$-N. 4. Higher $CO_2$ assimilation rate was shown in plants grown under $CO_2$ 1500ppm and 100:0 ratio of NO$_3$-N:NH$_4$-N. It dropped significantly with the increase of NH$_4$- N rates in nutrient solution. 5. Fresh weight, leaf number, root length and root weight of crisphead lettuce were far better in the treatment of $CO_2$ 1500ppm and 100:0 ratio of NO$_3$-N:NH$_4$-N. Growth differences by $CO_2$ elevation were not shown in other NO$_3$-N:NH$_4$-N treatments. 6. The highest nitrate contents of leaves were shown in NO$_3$-N single treatment but shown the lowest vitamin C contents. Nitrate contents of leaves were decreased by $CO_2$ but the effect was slight treatment.

• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.43-50
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• 2008

This study was conducted to investigate the proper supplied conditions of sodium selenate supplied by fertigation to improve functionality of major western vegetables; beet, broccoli, cabbage lettuce, celery, and parsley in highland. In this work, the growth and content of minerals, ascorbic acid, nitrate, and selenium were measured in western vegetables that treated sodium selenate by different concentration, treatment time and treatment frequency. While there was not different in early growth of some western vegetables among different concentration of sodium selenate; 1,2, 5 and $20\;mg{\cdot}L^{-1}$, at 20 days after treatment, the fresh weight was reduced 33% at cabbage lettuce,47% at broccoli, and 74% at parsley compared control in $5\;mg{\cdot}L^{-1}$ treatment. But the fresh weight of beet and celery reduced just 20% and 15% compared control in even $20\;mg{\cdot}L^{-1}$. The ascorbic acid of cabbage lettuce, celery, and beet increased as sodium selenate concentration increased, so that of cabbage lettuce showed 1.2 times compared control in $20\;mg{\cdot}L^{-1}$ treatment and also that of beet and celery increased 10%. But the ascorbic acid of broccoli and parsley was not influenced by treated sodium selenate. As the concentration of sodium selenate increased, the nitrate contents decreased regardless of crops compared control. This reduced effect of nitrate was highest in cabbage lettuce, followed by beet and celery. The mineral contents, such as K, Ca, and Mg, decreased in all crops, as the concentration of sodium selenate increased. The potassium content showed an obvious negative correlationship with the concentrations of sodium selenate regardless of crops, but the magnesium and calcium content did not show significant difference between treatments. The selenium content increased in proportion as increasing sodium selenate concentrations. The broccoli, celery and parsley treated $20\;mg{\cdot}L^{-1}$ sodium selenate showed 24.4 times, 76.4 times, and 560 times higher than control, respectively. When the sodium selenate supplied to some western vegetables in different growth stage, the selenium content increased 1.3 times and 1.4 times higher in early stage than in late stage in cabbage lettuce and broccoli, respectively. However in parsley and celery, the selenium content showed the highest in middle stage. The selenium content increased in proportion as increasing the sodium selenate treatment frequency, but in above 10 times treatment, the increased effect alleviated in parsley, celery, and cabbage lettuce. On the contrary, the selenium content of broccoli increased constantly as treatment frequency increased.

• Journal of Bio-Environment Control
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• v.23 no.3
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• pp.229-234
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• 2014

We analyzed drainage water from coir substrate in which cucumber plants were grown in winter and elucidated changes in pH, EC, and major nutrients according to the growth stages to recommend nutrient solution management appropriate to each growth stage. From the analysis of drainage solution the growth stages of cucumber were desirable to be divided into two, planting to fruit setting and fruit setting to harvest in case of nutrient solution management. The time required was about 3 weeks from planting to the first fruit setting and thereafter 7~10 days more until the first harvest. Approximately every 3~4 days were needed until the upper flowers bloomed. The time required from fruit setting to harvest was not different much among flowers as cucumber plants grew. From the experimental results, EC of supplied solution was recommended to maintain a little high to $3.0dS{\cdot}m^{-1}$ until before fruit setting and lower a little to $2.0{\sim}2.3dS{\cdot}m^{-1}$ after that. Of course, the amount of solution supply should be increased as plants grew. In case of each nutrients, the recommendation of concentrations of nitrogen, phosphorus and calcium were 700, 60, and $110mg{\cdot}L^{-1}$ each until before fruit setting, and then 660, 50, and $100mg{\cdot}L^{-1}$ each after fruit setting. The concentrations of potassium and magnesium are recommended to start from 400 and $80mg{\cdot}L^{-1}$ until fruit setting and lower a little after that.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.4
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• pp.258-269
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• 1982

The nutritional status of fruit leaves of sweet persimmon and soil conditions were observed in the fifty five blocks of fruit farms of sweet persimmon in Gimhae, Gyeong-nam area. 1. The soil of fruit farm was composed of more than 20% of gravel in the most part of the fruit farms. 2. The strong acidity was observed in the soil of young fruit farms but the acidity of the farm soils was improved to week acid with increase of age of fruit trees. 3. The great variation in the content of available phosphate were observed in the soil from different fruit farm blocks and the lime content were relatively low in the most of the farm soils. 4. The contents of nitrogen, phosphate and potassium in leaves of sweet persimmon collected in July and October were lower than those collected in May but reverse tendency was observed in the content of calcium, magnesium and sodium. 5. The content of boron in leaves collected in May was similar to that collected in July but extremely high content of boron was observed in the loaves collected in October, harvesting period of sweet persimmon. 6. The contents of iron and manganese in the leaves of sweet persimmon were observed to be relatively high compared to the content in the leaves of other fruit trees. 7. The relatively great variation in such inorganic components as iron, copper and boron was observed in the fruit leaves of sweet persimmon according to the different fruit farm blocks. 8. The ages of fruit trees didn't have an effect on the content of inorganic components in the fruit leaves except the content of nitrogen which was decreased with the increase of the ages of fruit trees.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.197-204
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• 1989

To evaluate the effect of soil improvement on the chemical properties and corn silage yield, this experiment was carried out in the newly-reclaimed sloped land. Corn (Suwon 19) was cultivated under the six different treatments including integrated improvement plot at Songjeong loam, 20 percent slope, from 1985 to 1987 and various soil chemical properties and silage yield were investigated. pH of topsoil was above 5.0 except for control and phosphate plot, but lime and integrated improvement plots were above 5.0 in subsoil. The contents of organic matter of topsoil were above 2.0% except control and subsoiling plot. Except control, the range of cation exchange capacity was 7.4-7.8 me/100g in topsoil, 7.0-7.7 me/100g in subsoil. Soil bacteria density of root zone was the highest in integrated improvement than the other treatments, and it was higher at the harvesting stage than the heading stage. Mean density of microorganism was $61.3{\times}10^5$ in bacteria, $21.5{\times}10^4$ in fungi and actinomycetes was B/F ratio was 28.5 and B/A ratio was 2.9. Vertical root distribution of total and 10cm depth below was more in the integrated improvement and subsoi ling plot than the other plots. Total nitrogen (T-N) content was higher in integrated improvement plot, and phosphate content of leaves was higher in compost and integrated improvement plot, but stem and grain were not different. Potassium content of the plant was higher in integra ted improvement plot. Correlation between dry matter yield and T-N was more significant than the other elements. And the contents of phosphate, calcium and magnesium were significant at 5%, but potassium was not.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.968-972
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• 2012

Soil chemical properties of agricultural soils in Korea were investigated at four-years interval in order of paddy, plastic film house, upland, and orchard soils since 1999. Paddy soil samples were taken from the surface 15 cm at 4,047, 2,010, 2,110 and 2,110 sites in all provinces of South Korea in 1999, 2003, 2007 and 2010, respectively. Soil chemical properties in Korea except Jeju province were measured. Soil pH and exchangeable calcium and available silicate contents increased with increasing the application rate of silicate fertilizer and with decreasing its application interval. Soil organic matter content also increased from $22.0g\;kg^{-1}$ in 1999 to $26.0g\;kg^{-1}$ in 2011. Average concentration of available phosphate in 2011 was higher than the upper limit of its optimal range for rice cultivation. However, exchangeable magnesium and available silicate contents were below the lower limit of their optimal ranges, which were 80% and 92% of them, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.140-146
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• 2010

Monitoring of the dynamic changes at paddy rice agriculture is very important for agricultural sustainability. Field monitoring was performed to evaluate the soil chemical properties of 260 paddy soil samples every four years from 1999 to 2007 in Gyeongnam Province. Soil chemical properties such as pH, organic matter, available phosphate, silicate, exchangeable potassium, calcium, and magnesium contents were analyzed. The contents of exchangeable cations, and available silicate were significantly increased in 2007 compared to 1999. The chemical contents of organic matter, exchangeable potassium, and magnesium were significantly increased in acid sulfate soil, and silty clay loam compared to those of other soil types, and textures. Especially, content of organic matter was significantly increased in hill area compared to other soil topographies, while exchangeable potassium was significantly decreased. Principle component analysis (PCA) of chemical properties in paddy soils was obtained with eigenvalues > 1 summing 39.1%of variance for PC1, 20.4%of variance for PC2, and 59.5%of the total variance in the all of soil chemical properties. Therefore, principal component analysis is more effective for monitoring from chemical properties of paddy soil.

• Journal of the Korean Wood Science and Technology
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• v.48 no.2
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• pp.206-216
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• 2020

This study was conducted to analyze the sap flow and composition by tapping date in Acer akamotoanum from an artificial forest in the City of Jinju. The sap was collected from five saplings (diameter at breast height10-20 cm) in two phases with an interval of a month. During phase 1 (January 10, 2019 - February 9, 2019) with daily mean temperature of 1.16±2.15℃, 60.59 liters of sap was collected over 32 days. Phase 2 (February 12, 2019 - February 22, 2019) with daily mean temperature of 2.55±1.30℃ yielded 13.38 liters of sap over 11 days, which was a reduction to 22% of the total sap flow in phase 1. The analysis of sugar composition in the collected sap from phase 1 and 2 showed that sucrose concentration was 2.5% at its highest during the earlier days of collection and decreased to 0.8% at the end. Glucose and fructose concentrations were measured near 0, and were lower than sucrose concentration. The most prominent inorganic elements in the collected sap were potassium (41.69 - 89.75 mg/kg), calcium (24.66 - 48.14 mg/kg) and magnesium (10.18 - 27.25 mg/kg). The contents of sucrose and inorganic components between the samples collected from phase 1 and 2 did not show significant differences. The sap flow amounts of A. okamotoanum from different tapping periods showed a notable variation, but there were no significant differences in the contents of sugar or inorganic elements.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.157-164
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• 2009

Background: Various studies and experimental trials have been done to develop bioprosthetic devices to treat complex congenital heart disease due to the limited usage of homograft tissue. The purpose of the present study was to evaluate the effect of diamine bridges with using L-lysine, as compared with using ethanol. Material and Method: Porcine pericardium was fixed at 0.625% GA (commercial fixation). An interim step of ethanol (80%; 1 day at room temperature) or L-lysine (0.1 M; 2 days at $37^{\circ}C$) was followed by completion of the GA fixation (2 days at $4^{\circ}C$ and 7 days at room temperature). The tensile strength and thickness of the porcine percardium were measured, respectively. The treated pericardiums were implanted subcutaneously into three-week old Long-Evans rats for 8 weeks. The calcium content of the implants was assessed by atomic absorption spectroscopy and the histology. Result: Ethanol pretreatment ($13.6{\pm}10.0ug/mg$, p=0.008), L-lysine pretreatment ($15.3{\pm}1.0 ug/mg$, p=0.002), and both treatment ($16.1{\pm}11.1ug/mg$, p=0.012) significantly inhibited calcification, as compared with the controls $(51.2{\pm}8.5ug/mg)$. L-lysine pretreatment ($0.18{\pm}0.02mm,\;1.20{\pm}0.30kg$ f/5 mm) significantly increased the thickness and tensile strength, as compared with ethanol pretreatment ($0.13{\pm}0.03mm,\;0.85{\pm}0.36$ 1.0 kg f/5 mm) (p<0.01, p=0.035). Conclusion: The diamine bridges using L-lysine seemed to decrease the calcification of porcine pericardium fixed with glutaraldehyde, and this was comparable with Ethanol. Additionally, it seemed to enhance the thickness and tensile strength.