• Journal of Korea Water Resources Association
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• v.45 no.8
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• pp.795-804
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• 2012

Recently, changes in rainfall intensity and patterns have been causing increasing soil loss worldwide. As a result, the water ecosystem becomes worse and crops yield are reduced with soil loss and nutrient loss with it. Many studies have been proposed to estimate runoff and soil loss to predict or decrease non-point source pollution. Although the USLE has been used for many years in estimating soil losses, the USLE cannot reflect effects on soil loss of changes in rainfall intensity and patterns. The WEPP, physically based model, is capable of predicting soil loss and runoff using various rainfall intensity. In this study, the WEPP model was simulated for sediment yield, runoff and peak runoff using data of 5, 10, 30, 60 minute term rainfall, Huff's method and design rainfall. In case of rainfall interval of 5 minutes and 60 minutes, the sediment and runoff values decreased by 24% and 19%, respectively. The peak rate runoff values decreased by 16% when rainfall interval changed from 5 minutes to 60 minutes, indicating the peak rate runoff values are affected by rainfall intensity to some degrees. As a result of simulating using Huff's method, all values (sediment yield, runoff, peak runoff) were found to be the greatest at third quartile. According to the analysis under various design rainfall conditions (2, 3, 5, 10, 20, 30, 50, 100, 200, 300 years frequency), sediment yield, runoff, and peak runoff of 906.2%, 249.4% and 183.9% were estimated using 2 year to 300 year frequency rainfall data.

• Korean Journal of Soil Science and Fertilizer
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• v.2 no.1
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• pp.31-38
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• 1969

This experiment was carried out to determine the effect of different levels of phosphate and potash firtilizers applied on yields and quality of leaf tobacco. It was done at all varying levels of phosphate and potassium fertilizers $S_0$ (non-fertilizer plot);N:P:K=0:0:0 (Kg/10a) $S_1$ (1/2 amount plot);N:P:K=10:7.5:10 (Kg/10a) $S_2$ (standard plot);N:P:K=10:15:20 (Kg/10a) $S_3$ (1.5 times plot);N:P:K=10:22.5:30(Kg/10a) $S_4$ (2.0times plot);N:P:K==10:30:40 (Kg/10a) Urea was applied as nitrogen, triple superphosphate as phosphate, potassium sulfate as potash source. The total amount of fertilizers was applied as basal dressing per one plant. This experiment was carried out by using randomized block design with 3 replication. The results obtained in terms of yields and quality are summarized as follows. 1. By increasing the amounts of phosphate and potassium fertilizers, growing status of the largest leaf length, the largest leaf width and stem size of tobacco increased in the order of $S_4>S_3>S_2>S_1>S_0$. 2. By increasing the amount of phosphate and potassium fertilizers, yield was increased in the order of $S_4>S_3>S_2>S_1>S_0$, This increase showed generally high significance among various levels of treatments. 3. The regressive equation was derived from the relationship between treatment levels and tobacco leaf yield. The most desirable treatment level for the maximum yield was estimated as the 2.87 times as much as the treatment level of phosphate and potasium fertilizers of standard plot. 4. By increased application of phosphate and potash fertilizers, the contents of $P_2O_5$ and $K_2O$ in the tobacco leaf became greater while the content of nicotine was decreased. Thus, a negative correlation between fertilizer application and nicotine content has been observed.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.166-170
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• 2013

BACKGROUND: Persimmon growers have often tried various regimens of K fertilization to improve fruit quality. This experiment was conducted to determine the effects of K rates on concentration of inorganic elements in different tree organs and on fruit characteristics. METHODS AND RESULTS: Six-year-old non-astringent 'Fuyu' persimmons, grown in 50-L pots, were used. Total K amounts of 0 (no-application), 12, 25, 37, and 66 g were fertigated to a pot with KCl solution at 3-to 4-day intervals from July to September. The 0 K trees received no K fertilizer for the two previous years. Leaves, fruits, and shoots were sampled in November. K concentrations in leaves and shoots increased significantly by increasing K rate; leaf K, 0.49% for the 0 K, increased to 3.09% for the 37 g and 3.11% for the 66 g trees. Fruit K was notably lower for the 0 K, but there were no significant differences among the trees as long as they were supplied with more than 12-g K. In the trees with 0 K, leaf necrosis in the margin was apparent in June and the symptom progressed toward the midrib. Some leaves scorch-rolled from the margin in August. The greatest effect of K rates was on fruit size; it significantly increased to 181 g for the 12 g, 203 g for the 37 g, and 206 g for the 66 g compared with 150 g for the 0 K trees. However, K rates did not affect firmness and soluble solids of the fruits. The fruits of the 0 K trees were characterized by better coloration. CONCLUSION(S): The K-rate effect on inorganic elements depended on tree organs and fruit size was the major parameter to be affected by the K rates.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1690-1698
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• 2012

As alcohol use is one of the most important risk factors for injuries, this study was intended to clarify and evaluate any relationship between drinking patterns and the incidence rates/specific characteristics of injuries in adult populations, using a widely accepted tool, the Alcohol Use Disorders Identification Test (chronic alcohol drinking behaviors measurement, hereinafter the AUDIT) developed by the World Health Organization to help to assess the behaviors in a more accurate and reliable manner. This study used the data collected from the 2009 Korea National Health and Nutrition Examination Survey (KNHANES), in which 7,511 of 7,893 adult participants aged ${\geq}19$ years answered the questions about injuries, and excluding 104 non-respondents, 6,258 of participants in the questionnaire survey of drinking patterns were finally analyzed. The incidence rates and specific characteristics of injuries as classified by the AUDIT categories (i.e., body regions, types and mechanisms) were assessed and estimated in terms of their relative risk using t-test, ANOVA, and logistic regression. SPSS 19.0 statistical package software was employed for statistical analyses. These analyses indicate that the incidence rates of overall injuries were significantly higher in male respondents than in female respondents. The risks of alcohol use related injuries were 8.3 times higher in male respondents than in female ones. Regarding educational background, high school graduates showed the highest rates in the AUDIT with significant difference from the other groups. The married group and the group of respondents having monthly income estimated at KRW 2.01 to 3 million also showed the highest rates in the AUDIT compared to the other groups, indicating statistically significant difference. Significantly increased in problematic drinkers and those with alcohol dependence, the incidence rate of injuries body regions was 0.0371 in the head/neck, and with respect to the AUDIT and the mechanisms of external causes of injuries, transport accidents ranked first, followed by slippage, others, crash and fall. In regard to the classified types of injuries, it was statistically significant in others (e.g., laceration, contusion, addiction, or penetrating wound). In conclusion, the mechanisms of external causes of injuries as well as injuries attributed to alcohol use are very important, and a strategy is required to reduce such the injuries in the manner of decreasing the frequency of drinking after motivation by professional counsellors.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.266-273
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• 2009

Use of plant growth promoting symbiotic and non-symbiotic free-living beneficial bacteria as external source of nitrogen is a major research concern for sustainable crop production in the $21^{st}$ century. In view of this, an experiment was conducted under controlled conditions to determine the effects of inoculation with Methylobacterium suomiense CBMB120, a plant growth promoting (PGP) root and shoot colonizer on red pepper, for the purpose of reducing external chemical nitrogen fertilization. Amendments with organic fertilizer and chemical fertilizer in the form of NPK were made at dosages of 50%, 75% and 100%, at 425 and $115kg/ha^{-1}$ measurements. The soil type used was loam, with a pH of 5.13. The growth responses were measured as plant height at 19, 36 and 166 days after transplantation and final biomass production after 166 days. It was found that inoculation with M. suomiense CBMB120 promotes plant height increase during the active growth phase at 19 and 36 days by 14.17% and 10.03%, respectively. Thereafter, the bacteria inoculated plantlets showed canopy size increment. A highly significant inoculation effect on plant height at p<0.01 level was found for 100% level of organic matter and chemical amendment in red pepper plantlets after 36 days and 19 days from transplantation. Furthermore, there was a significantly higher (10.30% and 6.84%) dry biomass accumulation in M. suomiense CBMB120 inoculated plants compared to un-inoculated ones. A 25% reduction in the application of chemical nitrogen can be inferred with inoculation of M. suomiense CBMB120 at with comparable results to that of 100% chemical fertilization alone. Enumeration of total bacteria in rhizosphere soil confirms that the introduced bacteria can multiply along ther hizosphere soil. Large scale field study may lead to the development of M. suomiense CBMB120 as an efficient biofertilizer.

• Journal of Life Science
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• v.19 no.9
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• pp.1314-1320
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• 2009

Histone deacetylase inhibitor (HDACI) is a new promising candidate as an antineoplastic agent for the treatment of solid and hematologic malignancies. In order to evaluate cell death and to elucidate the related mechanism(s) in NSCLC cells after HDACI, sodium butyrate (SB), a representative HDACI, was used to treat H460 cells for 48 hrs. SB exposure resulted in a significant reduction of cell viability at concentrations below 7.5 mM, and about 50% of cell death occurred at 20 mM. The types of cell death induced by SB were both apoptosis and necrosis, evaluated by Annexin-V staining combined with propidium iodide. SB treatment significantly evoked G2/M cell cycle arrest and subsequently induced cell death with caspase-dependent manner. While ERK protein content was not altered after SB, phosphorylated forms of ERK were markedly reduced. Taken together, SB is significantly able to induce cell death in NSCLC cell line H460, and it is suggested that the reduction of ERK phosphorylation might be closely involved in the cancer cell death mechanism initiated by HDACI.

• Tuberculosis and Respiratory Diseases
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• v.59 no.3
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• pp.279-285
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• 2005

Background : Ambient particles during Asian dust events are usually less than $10{\mu}m$ in size, and known to be associated with the adverse effects on the general population. There is little evidence linking Asian dust to adverse effects on the airways. In 2002, the authors found that particulate matter during Asian dust events had an effect on the symptoms and pulmonary function of patients with bronchial asthma. An aggravating factor might be that of a viral infection, but this remains unclear. Conversely, it has been speculated that African dust may carry the virus responsible for foot and mouth disease. Asian dust events are also likely to be responsible for transporting viruses, some of which are pathogenic, and common in many environments. Therefore, in this study, air samples were screened for the presence of viruses. Methods : Air samples were collected 20 times each during Asian dust events and under non-dust conditions, for at least 6 hours per sample, using a high volume air sampler (Sibata Model HV500F), with an airflow rate of 500L/min, between April and August 2003, and between April and August 2004. The samples were then screened for the presence of targeted viruses (Influenza A, B, Hog cholera virus, and Aphthovirus) using a polymerase chain reaction method. Results : One Asian dust event occurred between April and August 2003, and 3 between April and August 2004, with a 24 hour average PM10 level of $148.0{\mu}g/m^3$. The 24 hour average PM10 level was $57{\mu}g/m^3$. There was a significant difference in the PM10 concentration between dusty and clear days. No viruses (Influenza virus, Aphthovirus, and Hog cholera virus) were identified in the air samples obtained during the dusty days. Conclusions : Although no virus was detected in this study, further studies will be needed to identify suspected viruses carried during Asian dust events, employing more appropriate virus detection conditions.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.469-474
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• 2006

This study was carried out to investigate the changes of physicochemical characteristics of Schizandra chinensis during postharvest ripening for 8 days at various temperatures. The juice yield of S. chinensis, which was 55.7% before postharvest ripening, was unchanged $(55.3{\pm}0.6-56.3{\pm}0.6%)$ at $4^{\circ}C$ storage, but was decreased at the level of 6 and 7% at $25^{\circ}C$ and room temperature (RT), respectively. During storage at $25^{\circ}C$ and RT, the titratable acidities of S. chinensis were the highest at $7.49{\pm}0.03$ and $7.20{\pm}0.03%$ after 6 days of postharvest ripening, respectively. During storage at $25^{\circ}C$ and RT, the soluble solid content of S. chinensis was increased from $8.2{\pm}0.1%$ at initial stage to a peak of $12.2{\pm}0.15%$ at 6-day storage, after which it decreased. L values (lightness) of S. chinensis were increased in all treatments during storage, and a values (redness) of $25^{\circ}C$ and RT treatments were increased from 5.04 initially to 6.77 and 7.65 at 8-day storage, respectively. The major free sugars of S. chinensis were fructose (0.55%), glucose (0.56%), and sucrose (0.50%). During storage at $25^{\circ}C$ and RT, the fructose and glucose contents were continually increased with increasing storage period, while the sucrose contents decreased after 6-day storage. Major non-volatile organic acids of S. chinensis were succinic (1.21%), citric (0.17%), and malic (0.07%) acids. Changes in the organic acids contents of S. chinensis at various temperatures showed a similar tendency to that of the free sugars. We estimated that the best conditions for the postharvest ripening of S. chinensis were 8 days at $4^{\circ}C$ storage, and 6 days at $25^{\circ}C$ and RT.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.357-370
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• 1982

Recent concern regarding price and availability of fossil fuels has spurred the interest in alternative sources for farm crop drying. Among the available options such as biomass energy, wind power, nuclear energy and solar energy etc., the increasing attention is being directed to the utilization of heat from solar energy especially for farm crop drying. Even though solar energy is dispersed over a large land area and only a relatively small amount of energy can be simply collected, the advantages of solar energy is that the energy is free, non-polluting. The study reported here was designed to help supply the informations for the development of simple and relatively inexpensive solar warehouse for farm crop drying and storage. Specifically, the objectives of this study were to determine the performance of the solar collector fabricated, to compare solar supplemented heat drying with natural air drying and to develop a simulation model of temperature in stored grain, which can be used to study the effects due to changes in ambient air temperature. For those above objectives, solar collector was fabricated from available materials. Corrugated steel galvanized sheet, painted flat black, was used as absorbers and clear 0.2mm polyethylene sheet was the cover material. The warehouse for rough rice drying and storage was constructed with concrete block, and the solar collector was used as the roof of warehouse instead of original roofing system of it. The results obtained in this study were as follows: 1. The thermal efficiency of the solar collector was average 26 percent and the overall heat transfer coefficient of the collector was approximately $25kJ/hr.m^2\;^{\circ}K$. 2. Solar heated air was sufficient to dry one cubic meter of rough rice from 23.5 to 15.0 percent in 7 days and natural air was able to dry the same amount of rough rice from 20.0 to 5 percent in l2 days. 3. Drying with solar heat reduced the required drying time to dry the same amount of rough rice into a half compared to natural air drying, but overdrying problems of the bottom layer were so severe that these problems should be thoroughly analyzed. 4. Simulation model of temperature in stored grain was developed and the results of predicted temperature agreed well with test results. 5. Based on those simulated temperature, changes in the grain-temperature were a large at the points of the wallside and the damage of the grain would be severe at the contact area of wall.

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.9-13
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• 2007

The objective of this study was to investigate the relationship between various estrous behavior and ovulation time, and to determine which estrous behavior could predict ovulation time more accurately. In total, 37 ovulations and 28 estrous detection were observed in 51 Holstein-Friesian dairy cows. Various estrous behavior were observed during 72 h from two days after $PGF_2{\alpha}$ injection and their relation with the time of ovulation (ultrasound examinations at 4-h intervals) was investigated. In estrous periods, the rate of sniffing, chin resting, mounting, standing heat was 81%, 78%, 78% and 56%, respectively. Ovulation occurred $25.6{\pm}7.9h$ after onset of estrus (ranging between 7 and 37h) and $13.4{\pm}7.1h$ after end of estrus (ranging between 1 and 28h). Interval between onset of estrus and ovulation time was significantly (p<0.05) shorter for standing heat $(17.33{\pm}5.83h)$ than for mounting, sniffing and chin resting $(23.58{\pm}5.12h,\;24.25{\pm}6.09h,\;23.42{\pm}6.04h)$. In 88% of the animals that displayed mounting, ovulation occurred between $16{\sim}28h$ after onset of mounting. Onset of standing heat, sniffing and chin resting occurred between $10{\sim}22(81%)h,\;16{\sim}28(79%)h\;and\; 19{\sim}31(79%)h$ before ovulation respectively. Sniffing and chin resting were displayed during the non-estrous period and are therefore, not useful predictors of ovulation time. The standing heat and mounting can be a good predictor for time of ovulation but the disadvantage of using standing heat is that only a limited number of cows display standing heat. Thus, it is concluded that mounting behavior could be the best predictor for time of ovulation.