• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.102-108
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• 2006

It is very important to improve fertilizer use efficiency for the saving of fertilizers and for environmental purposes as well. However, there was no effective ways for the fertilization in the mid of growth under the plastic film mulching cultivation so far. For this, a Band Spotty Fertilization (BSF) machine was developed recently. So, we tried to establish a low input fertilization technique using this BSF machine in the vinyl mulching cultivation of onion (Allium cepa L.). Fertilization efficiency, soil properties, and crop yield were examined and compared among treatments from 2000 to 2001. The content of exchangeable K in soils were higher after fertilization but that of available $P_2O_5$ was lower than before the experiment in all plots. The content of nitrate-N was highest at the early growth stage, and higher in BSF plots than that of conventional fertilization (CF). BSF plot showed higher growth rate, and uptake amount of nitrogen of onion by 59-69% than that of CF. N use efficiency in BSF was higher in the order of two time-split application, one time-split application, and three time application. K use efficiency was high 13-17% BSF plots than that in CF($63kg\;ha^{-1}$) plots. The amount of residual N in soils was high by 8-14% in BSF plots compared to that in CF plots, and the loss of N was lowered 26-34% by BSF. Also, the amount of residual K in soils was high by 13-18% and the loss of K was low by 29-31% in BSF plots compared to that in CF plots. The yield of onions increased by 7-13% by BSF due to increased diameter and weight of bulbs. As the results, N fertilization efficiency increased by 22-42% by BSF.

• Journal of Sericultural and Entomological Science
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• v.15 no.1
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• pp.37-48
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• 1973

The purpose of this studies is to improve the cohesion of raw silk through various analyses on cocoon drying, cooking, reeling, re-reeling, and on the properties of water. Also we investigated the correlation between silk testing items which we have reached to the following results. 1. Drying of cocoon When cocoons were slowly dried with 100$^{\circ}C$, the results of cohesion became much better. On the other hand, the results were considerably decreased in case the temperature with 115$^{\circ}C$. 2. Cooking of cocoon In case of the cooking of cocoon, we found that the result of cohesion was best with incomplete cooking, that of the control was next, while in over cooking, the results were very low. Also the results of cohesion were much better when using the method of over cooking with sericin arrestive agent than that of incomplete cooking with sericin agglutinating agent. 3. Reeling of cocoon A) When the temperature of reeling bath was 25-45$^{\circ}C$, the results of cohesion test were much better, but at the temperature below 25$^{\circ}C$ or above 45$^{\circ}C$, the results became worse. B) With out the process of croissieur, the results of cohesion were too bad, but in case of croissieur more than 1cm, cohesion became better rapidly. Further more, we understood that the results of cohesion were improving slightly with longer length of croissieur. C) When the velocity of reeling was increased, the results of cohesion also improved. The best results were shown when reeling velocity was 180-220 r.p.m. But when the velocity was increased more than 220 r.p.m., the results of cohesion got worse more or less. D) When the temperature of the drying pipe in reeling machine was raised, the results of cohesion also showed a tendency to improve. 4. Re-reeling A) We could net reach a conclusion as to have correlation between the number of dipping repeat in vacuum tank and the results of cohesion before re-reeling process. B) When we used Seracol 500 as an agglutination protective agent with l/1000 to l/2000 of water, the results of cohesion test were better. C) When we used Pearl-lite as an agglutination protective agent with 1/1000 to 1/2000 of water, the results of cohesion were considerably better. D) We gained tile best results when used Cohesion Improving Chemical, A-80, with 500-1500 times diluted. 1) Results of cohesion was improved when humidity was low or temperature was high in the rereeling machine. 5. Filature water A) The water pH near the isoelectric point of protein showed the best cohesion, but the farther water pH, the worser results were obtained. B) With the increasing of M-alkalinity in filature water, the results of cohesion were worse. Above all, we understood the tendency of the results of cohesion get worse when the M-alkalinity is increased above 200 ppm. C) By increasing the total hardness of the filature water, it improved the results of cohesion. Especially, when the total hardness was above 300ppm, the results were extremely high. 6. Effects combination of each results A) The result of effects combination in filature processes with the obtained best conditions was distinctively improved. But the results could not reach in mathematicaly double effect. When reelied under worse conditions, the results of cohesion test were too bad. There was "effect limit" for the promotion. B) Generally the results of cohesion were bad when the filature conditions(the temperature, pressure and the properties of water, etc) are processed as sericin loss to be high. On the other hand, the results were very good when lower sericin loss was controlled in filature conditions. C) When filature conditions such as reeling velocity and croissieur length provide pysical cohesion ability and when raw silk dry fast during reeling and re-reeling, we found the result of cohesion was better. 7. Correlation of silk testing items. A) A negative correlation exists between the results of cohesion test and cleanness defect. Another word, the result of cohesion test was found to be worse as cleanness defect increased. B) In cleanness, cohesion has negative correlation against the number of slugs, but we could not find any correlation against long loops, loose ends. C) Cohesion has negative correlation against average neatness and low neatness defect. The better the results of neatness respectively, the better the results of cohesion found. D) There is no correlation between tenacity and the results of cohesion test, but there was high positive correlation between the results of elongation and those of cohesion test. The more elongation, the better the results of cohesion was found.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.242-248
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• 1992

This study was carried out to investigate the effects of root-zone temperature in hydroponics on the plant growth and nutrient uptake of lettuce(Lactuca sativa L), tomato (Lycopersicon esculentum Mill), and cucumber (Cucumis sativus L). Respiration rate in roots increased with increase in root-zone temperature. At $10^{\circ}C$ of root-zone temperature, respiration rate in lettuce root was higher than those in tomato and cucumber. Increasing rate of root respiration in tomato with increase in root-zone temperature was greater than those in lettuce and cucumber. The lowest dry weight and leaf area of the crops studied were obtained at $10^{\circ}C$ of root-zone temperature, but they were not different between 20 and $30^{\circ}C$. Increase in root-zone temperature generally resulted in increase in T/R ratio and net assimilation rate. At the low root-zone temperature, root growth and leaf area of tomato and cucumber were severely affected. Relative growth rates of lettuce and cucumber were also greatly reduced by the low root-zone temperature. Contents of N, P, K, Ca, and Mg in the crops increased as root-zone temperature increased from 10 to $20^{\circ}C$, whereas only Ca content in tomato and cucumber increased with increase in root-zone temperature to $30^{\circ}C$. Remarkably low contents of P and Mg in the crops were found at the low root-zone temperature. Inhibition of plant growth and nutrient uptake due to low root-zone temperature was much greater in cucumber than in lettuce and tomato.

• Food Science of Animal Resources
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• v.31 no.6
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• pp.921-927
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• 2011

To compare pork quality from different pig species domesticated for Korean consumers, the meat quality characteristics of 5 different pure breeds of Landrace (L), Yorkshire (Y), Duroc (D), Berkshire (B), and Chester White (C) were determined from the 3 parts of loins, butts, and bellies. The fat content of loins was higher in breed D than in the other breeds, while that of butts and bellies was higher in breed B. The CIE color $a^*$ and $b^*$ values of the loins and butts from breed C were lower than those of the other breeds, but the color values of the belly part did not significantly differ by breed due to the high fat accumulation. The drip loss and cooking loss significantly differed depending on meat parts: breeds D and B were inferior in loins and butts but superior in bellies. The lipid oxidation of raw meat did not increase during the 7 d storage. The cooked butts of breed C had less thiobarbituric acid-reactive substances values than those of the other breeds at 7 d, and the cooked bellies of breeds D and B had less. Moreover, there were only minimal differences in fatty acid compositions by pork breed and part. From the view points of the physicochemical and organoleptic analysis of pork from different pig species, it is estimated that breed D had better meat quality in the loin part and breed B had better meat quality in the butt. The belly meat quality of breed C showed the least value. Although the meat quality of pig species differed depending on the parts and it was difficult to compare the meat quality of a part using the meat quality parameters of another part, the result of this study could provide basic information that can be used to improve the meat quality of different parts of pig species.

• Tuberculosis and Respiratory Diseases
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• v.65 no.5
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• pp.379-384
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• 2008

Background: Sputum decontamination with NALC-NaOH (N-acetyl-L-cysteine-sodium hydroxide) is known to better detect Mycobacterium tuberculosis (M. tb) by culture than that with using NaOH, which is widely used in Korean hospitals. In this report, sputum samples collected from pulmonary tuberculosis (TB) patients were treated with either NaOH or NALC-NaOH, and we compared the results of smear and culture positivity to determine whether the NALC-NaOH treatment method improves culture positivity in the sputum samples, and especially for those sputum samples that are smear negative and scanty. Methods: For each decontamination method, 436 sputum samples from pulmonary TB patients in the National Masan Tuberculosis Hospital were collected for this study. Sputum from a patient was collected two times for the first and second day of sampling time, and these samples were employed for the decontamination process by performing the 4% NaOH and NALC-2% NaOH treatment methods, respectively, for detecting M. tb by an AFB (Acid Fast Bacilli) smear and also by culture in solid Ogawa medium. Results: The NaOH and NALC-NaOH treatment methods did not significantly affect the AFB smear positivity of the sputum samples (33.0% vs 39.0%, respectively, p=0.078). However, the culture positive percents of M. tb in the Ogawa medium treated with NALC-NaOH and NaOH were 39.7% and 28.0%, respectively, which was a significantly different (p=0.0003). This difference in culture was more prominent in the sputum samples that were smear negative (the positive percents with NALC-NaOH and NaOH were 15.8% and 7.2%, respectively, p=0.0017) and scanty (NALC-NaOH and NaOH were 60.8% and 42.9%, respectively, p=0.036), but not for a smear that was 1+ or higher (p>0.05). Conclusion: NALC-NaOH treatment is better than NaOH treatment for the detection of M. tb by culture, but not by smear, and especially when the AFB smear is negative and scanty.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.2-4
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• 1998

Proliferation of Nocardia amarae cells in activated sludge has often been associated with the generation of nuisance foams. Despite intense research activities in recent years to examine the causes and control of Nocardia foaming in activated sludge, the foaming continued to persist throughout the activated sludge treatment plants in United States. In addition to causing various operational problems to treatment processes, the presence of Nocardia may have secondary effects on the fate of heavy metals that are not well known. For example, for treatment plants facing more stringent metal removal requirements, potential metal removal by Nocardia cells in foaming activated sludge would be a welcome secondary effect. In contrast, with new viosolid disposal regulations in place (Code o( Federal Regulation No. 503), higher concentration of metals in biosolids from foaming activated sludge could create management problems. The goal of this research was to investigate the metal sorption property of Nocardia amarae cells grown in batch reactors and in chemostat reactors. Specific surface area and metal sorption characteristics of N. amarae cells harvested at various growth stages were compared. Three metals examined in this study were copper, cadmium and nickel. Nocardia amarae strain (SRWTP isolate) used in this study was obtained from the University of California at Berkeley. The pure culture was grown in 4L batch reactor containing mineral salt medium with sodium acetate as the sole carbon source. In order to quantify the sorption of heavy metal ions to N amarae cell surfaces, cells from the batch reactor were harvested, washed, and suspended in 30mL centrifuge tubes. Metal sorption studies were conducted at pH 7.0 and ionlc strength of 10-2M. The sorption Isotherm showed that the cells harvested from the stationary and endogenous growth phase exhibited significantly higher metal sorption capacity than the cells from the exponential phase. The sequence of preferential uptake of metals by N. amarae cells was Cu>Cd>Ni. The specific surFace area of Nocardia cells was determined by a dye adsorption method. N.amarae cells growing at ewponential phase had significantly less specific surface area than that of stationary phase, indicating that the lower metal sorption capacity of Nocardia cells growing at exponential phase may be due to the lower specific surface area. The growth conditions of Nocardia cells in continuous culture affect their cell surface properties, thereby governing the adsorption capacity of heavy metal. The comparison of dye sorption isotherms for Nocardia cells growing at various growth rates revealed that the cell surface area increased with increasing sludge age, indicating that the cell surface area is highly dependent on the steady-state growth rate. The highest specific surface area of 199m21g was obtained from N.amarae cell harvested at 0.33 day-1 of growth rate. This result suggests that growth condition not only alters the structure of Nocardia cell wall but also affects the surface area, thus yielding more binding sites of metal removal. After reaching the steady-state condition at dilution rate, metal adsorption isotherms were used to determine the equilibrium distributions of metals between aqueous and Nocardia cell surfaces. The metal sorption capacity of Nocardia biomass harvested from 0.33 day-1 of growth rate was significantly higher than that of cells harvested from 0.5- and 1-day-1 operation, indicatng that N.amarae cells with a lower growth rate have higher sorpion capacity. This result was in close agreement with the trend observed from the batch study. To evaluate the effect of Nocardia cells on the metal binding capacity of activated sludge, specific surface area and metal sorption capacity of the mixture of Nocardia pure cultures and activated sludge biomass were determined by a series of batch experiments. The higher levels of Nocardia cells in the Nocardia-activated sludge samples resulted in the higher specific surface area, explaining the higher metal sorption sites by the mixed luquor samples containing greater amounts on Nocardia cells. The effect of Nocardia cells on the metal sorption capacity of activated sludge was evaluated by spiking an activated sludge sample with various amounts of pre culture Nocardia cells. The results of the Langmuir isotherm model fitted to the metal sorption by various mixtures of Nocardia and activated sludge indicated that the mixture containing higher Nocardia levels had higher metal adsorption capacity than the mixture containing lower Nocardia levels. At Nocardia levels above 100mg/g VSS, the metal sorption capacity of activate sludge increased proportionally with the amount of Noeardia cells present in the mixed liquor, indicating that the presence of Nocardia may increase the viosorption capacity of activated sludge.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.289-294
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• 2012

Chrysanthemum morifolium (C. morifolium) is a perennial plant herb widely distributed in Korea and has been used in a traditional herbal remedy for various diseases. This study was conducted to determine antioxidant activities and antigenotoxic effect in water, acetone, ethanol and methanol extracts from white and yellow C. morifolium flowers (WC and YC). The antioxidants properties were evaluated on the basis of total phenolic content (TPC), DPPH radical-scavenging activity (RSA) and superoxide dismutase (SOD)-like activity. The highest TPC (5.09 g/100 g GAE) showed in YC methanol extract. The DPPH RSA activity of WC and YC water extracts increased as its concentration increase from 50 to 1000 mg/mL, respectively, and the lowest $IC_{50}$ of DPPH RAS showed in YC of $25^{\circ}C$. Also, WC solvent extracts showed significantly higher DPPH RSA than YC solvent extracts. The SOD-like activity of YC water extracts were higher than WC water extracts. And, YC acetone extract and WC methanol extract showed significantly higher SOD-like activity than WC acetone extract and YC methanol extract, respectively. The antigenotoxicity of WC and YC extracts were determined by measuring inhibitory effects of $H_2O_2$ induced DNA damage in human leukocytes using the comet assay, resulting that the ethanol extracts of WC and YC showed a significant antigenotoxic effect against oxidative stress. These results suggest that C. morifolium has significant antioxidant activity and protective effect against oxidative DNA damage.

• Neonatal Medicine
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• v.18 no.1
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• pp.89-95
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• 2011

Purpose: Hypernatremia most frequently occurs in the immature newborn and be severe in association with intraventricular hemorrhage (IVH). This study examined the frequency, onset and risk factors of hypernatremia, and the relationship between hypernatremia and IVH in very low birth weight (VLBW; <1,250 g) infants. Methods: We retrospectively reviewed the medical records of 55 VLBW infants admitted between January 2006 and December 2009 to the neonatal intensive care unit of Wonkwang University Hospital and who survived over 7 days. Serum sodium concentration, sodium intake, fluid and weight loss, as suggested risk factors of hypernatremia, and the incidence of IVH were evaluated. The infants were divided into a hypernatremia group (${\geq}$150 mEq/L) and nonhypernatremia group, and were compared. Results: Incidence of hypernatremia in the VLBW infants was 52.7%, and mean starting time of hypernatremia was 2.8${\pm}$1.3 days. There were no differences in the sodium and fluid intake between the two groups. Weight loss at day 3 after birth was significantly higher in the hypernatremia compared to the nonhypernatremia group (P<0.05); thereafter weight loss was non-significantly higher. The incidence of IVH in VLBW infants was 38.2%, and the difference between the two groups was not significant. Conclusion: Hypernatremia occurs commonly in VLBW infants and is most commonly caused by weight loss in the early days after birth. Incidence of IVH is not likely influenced by hypernatremia with marginally elevated sodium concentration.

• Clinical and Experimental Pediatrics
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• v.46 no.1
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• pp.17-23
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• 2003

Purpose : Cholestasis is a major complication in prolonged use of TPN, especially in the neonatal period, but there are few long-term reviews examining the clinical course in premature infants. Thus, in this study, we reviewed premature infants with TPN-associated cholestasis(TPNAC) to determine the incidence, clinical courses and possible risk factors. Methods : Retrospective review of 66 premature infants less than 2,000 gm of birth weight and on TPN for more than two weeks was performed. Cholestasis was defined as a serum direct bilirubin level greater than 2.0 mg/dL. The clinical course of cholestasis was described, and perinatal risk factors were evaluated. Results : TPNAC developed in 21 out of 66 infants(31.8%). The onset was $41.7{\pm}17.4days$ after receiving TPN, and the mean duration was $33.6{\pm}23.4days$. The incidence of TPNAC was significantly correlated with birth weight, and gestational age, and duration of TPN. But, possible etiologic factors, such as incidence of perinatal asphyxia or infection, showed no remarkable differences between infants with TPNAC and those without TPNAC(control). The enteral intake in the third postnatal week was significantly smaller in infants with TPNAC than in the control infants(P=0.033). Conclusion : The enteral intake in the third postnatal week was smaller in the infants with TPNAC than in the control infants. Thus, the incidence of TPNAC may be reduced by increasing the amount of oral intake during TPN in high risk infants.

• Clinical and Experimental Pediatrics
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• v.51 no.8
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• pp.879-885
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• 2008

Purpose : The human lung fibroblast may act as an immunomodulatory cell by providing pro-inflammatory cytokines and chemokines, which are important in airway remodeling. Vascular endothelial growth factor (VEGF) induces mucosal edema and angiogenesis. Thymus and activation regulated chemokine (TARC) induces selective migration of T helper 2 cells. We investigated whether human lung fibroblasts produced VEGF and TARC, and the effects were augmented with the co-culture of fibroblasts and human bronchial smooth muscle cells (HBSMC), and whether dexamethasone can inhibit the proliferation and the release of VEGF in lung fibroblasts. Methods : Human lung fibroblasts were cultured with and without HBSMC, growth-arrested in serum-deprived medium, and pretreated with dexamethasone for 16 hours. After 24-hour stimulation with platelet derived growth factor-BB (PDGF-BB) and/or transforming growth factor-${\beta}$ (TGF-${\beta}$), culture supernatant was harvested for assays of VEGF and TARC. Cell proliferation was assayed using BrdU cell proliferation ELISA kit. Results : 1) The release of VEGF was significantly increased after stimulation with TGF-${\beta}$, and its release was augmented when co-stimulated with PDGF and TGF-${\beta}$. 2) VEGF release induced by PDGF or TGF-${\beta}$ was inhibited by dexamethasone. 3) There was no synergistic effect on the release of VEGF when human lung fibroblasts were co-cultured with HBSMC. 4) Dexamethasone did not suppress human lung fibroblasts proliferations. 5) Neither TGF-${\beta}$ nor PDGF induced TARC release from lung fibroblasts. Conclusion : Human lung fibroblasts may modulate airway remodeling by release of VEGF, but they have no synergistic effects when co-cultured with HBSMC. Dexamethasone suppresses VEGF release, not proliferation of lung fibroblast.