• Journal of Korean Society of Transportation
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• v.25 no.4
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• pp.123-133
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• 2007

This study analyzed whether a transit network with hierarchy is efficient or not, and if transit network hierarchy has cost efficiency, then which condition guarantees the efficiency of the transit network hierarchy. The authors modeled the total cost of the transit network and suggested the conditions in which the transit network hierarchy has cost efficiency through comparing the cost of the transit network with and without hierarchy. The efficiency of transit network hierarchy is guaranteed when the travel cost savings induced by using a higher hierarchy transit network is larger than the increasing non-travel cost, which is the sum of access cost, waiting cost, and operating cost, induced by the introduction of a higher hierarchy transit network. This result is consistent with common sense and with the concept of cost and benefit analysis. If a passenger traveling within the area divided by a higher hierarchy transit network uses only a lower hierarchy transit network and the passenger traveling out of the area divided by the higher hierarchy transit network uses both lower and higher hierarchy transit networks, the travel demand using the higher hierarchy transit network is inversely proportional to the square of the line spacing. This means that the transit network becomes more efficient and small increases of travel demand guarantee the efficiency of the transit network hierarchy as the connectivity of the network becomes higher. This result shows that transit networks have economies of aggregation. This study is the first analytical research on transit network hierarchy and is expected to be a basis for numerical research. However, numerical research should complement this study, since analytical research has some limitations for considering a real network.

• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.167-173
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• 2005

Three different cDNAS for cinnamate 4-hydroxylase (C4H) which are involved in the second step of the general phenylpropanoid pathway were isolated and designated as pc4h1 (1,755 bp), pc4h2 (1,655 bp), and pc4h3 (1,316 bp), respectively. The nucleotide sequence analysis revealed that both pc4h1 and pc4h2 clones encode polypeptides of 505 amino acids frame but pc4h3 clone was truncated at the 5'-end of coding region. The alignment of the deduced amino acid sequences showed that PC4H1 and PC4H2 are highly homologous (95.8% identical) with each other and contain three conserved domains which are typical in cytochrome P450 monooxygenase: proline-rich region, threonine-containing binding pocket for the oxygen molecule, and heme binding region. In addition, result of the phylogenic tree analysis revealed that both pepper C4Hs belong to Class 1. pc4h2 transcription was strongly induced in wounded fruit (400%) and root (200%) relative to its very low basal level but not in leaf or stem tissue. In case of pc4h1, the basal level of transcription was higher than pc4h2 but induction by wounding was lower in fruit and root while leaf and stem tissues did not respond to wounding. The basal level of pc4h3 transcripts was not, if any, detectable and response to wounding was not observed.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.13-18
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• 2003

This study was carried out to investigate the expression patterns of foreign gene that controlled by tuber-specific patatin promoter in transgenic potatoes. Potato leaf disc cultured in vitro were transformed by the Agrobacterium strain LBA4404 containing pBl121 or pATGUS from potato cv. Desiree. In order to select the transgenic lines, gene-specific primers deduced from the NPTII were synthesized and used for polymerase chain reaction. The down part of the putative transgenic potatoes was transplanted weekly onto sucrose-enriched medium to accelerate the microtuber formation. RNA gel blot analysis was performed on the total RNAs obtained from tuber that had been harvested at a week interval. Also, histochemical assay was observed in the explants transformed with either pBI121 or pATGUS. Results showed that the transgenic plant containing pATGUS expressed GUS transcripts mainly at the tuber, not in stem, with the highest expression level in 5 weeks-grown microtubers. In contrast to pATGUS plants, the transformed plants with pBI121 showed an equal expression pattern throughout the whole developing stages. Consistent with RNA gel blot analysis, histochemical GUS staining and enzyme activity exhibited pATGUS transcripts were at the highest level in 5 weeks cultures. From these results, we suggest that the best stage to analyze the foreign gene introduced by patatin promoter into potato plants is at 5 weeks cultures after tuber formation.

• Pediatric Infection and Vaccine
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• v.7 no.2
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• pp.201-210
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• 2000

Purpose : We observed response to PPD skin test and local side reactions among subjects who received inoculation with Tokyo 172 BCG strain by percutaneous method using multiple puncture device. Methods : 138 infants and young children were enrolled at Yongdong Severance Hospital and 7 private clinics. 5TU PPD skin test were performed at 4 months after inoculation. The local reactions at multiple puncture site were observed in 3 days, 4~6 weeks, 36 weeks, and 48 weeks after inoculations and physical check up was done for evaluation of lymphadenopathy. Results : During 48 weeks of observation period, 96 subjects among 138 who were enrolled were followed up completely with records of PPD skin test and observation of local side reactions, presenting with the photos. The size of the induration after 48 hours of PPD skin test, was less than 5mm in six subjects(6.3%), greater than 10mm in sixty seven subjects(70.0%) and greater than 12mm in forty six subjects(47.9%). All subjects showed inflammatory reaction and pustules at multiple puncture sites and only just small papules, ulcer and pustules remained 4-6 weeks later. Eight to twelve weeks later, all local inflammatory skin reactions disappeared with remaining crust. After 48 weeks, 4(4.2%) subjects showed no scar with only faint stain on the puncture site. More than 70% of subjects showed more than 10 faint pin-point scars on the sites. However, the size of scar was clearly smaller compared to that of intradermal inoculation. There were no cases of lymphadenopathy. Conclusion : We observed good immune response to 5TU PPD skin test among the infant and young children who were immunized with percutanous inoculation of Tokyo 172 BCG strain. We could not find any severe local scar at inoculation sites. A degree of satisfaction of the parents whose children received the percutaneous injection was very high.

• Pediatric Infection and Vaccine
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• v.12 no.1
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• pp.61-66
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• 2005

Purpose : Since hepatitis A virus almost is transmitted by fecal-to-oral route, individual and public sanitation affects the prevalence and ages of hepatitis A infection. We researched the positivity rate of hepatitis A antibody at Pohang to make the basic data for subclinical infection and vaccination schedule. Methods : From January 2004 to February 2005, a total of 603 patients who were admitted at Hangdong University Sunlin Hospital, Dongguk University Hospital, and Christianity Hospital without any hepatic disease and vaccination of hepatitis A were enrolled. IgG antibody to hepatitis A virus were measured by electrochemiluminescence immunoassay(ECLIA). Results : Among 603 patients, 523 patients were less than 15 year of age and 80 patients were in above 15 years. The prevalence rate was 19.3%(101/523) in pediatric group and 70.0%(56/80) in above 15 years. In detail, the prevalence rate was 73.2%(52/71) in 0~5 months, 14.9%(11/74) in 6~11 month, 8.9%(7/79) in 12~17 month, 7.3%(6/82) in 18~23 month, 5.5%(4/72) in 2~3 years, 12.1%(9/74) in 4~8 years, 16.9%(12/71) in 9~14 years, 52.5%(19/40) in 15~29 years, and 92.5%(37/40) in group aged over 30 years. The prevalence rates in male and female showed no significant differences. Conclusion : The prevalence rate of hepatitis A in the group of 4~8 years and 9~14 years at Pohang was lower comparing with previous reports of other cities in Korea. We can postulate that the sanitation of children living at Pohang is at least not bad than other cities. And for the prevalence rate of hepatitis A is increased after 3 years, we should recommend that the vaccination of hepatitis A may be finished until 3 years.

• Childhood Kidney Diseases
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• v.18 no.1
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• pp.18-23
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• 2014

Purpose: The pharmacokinetics of tacrolimus, one of the most widely used immunosuppressive drugs, are known to vary by sex, age, and ethnicity during pediatric transplantation. This study assessed the pharmacokinetic characteristics and associated factors of tacrolimus in Korean children receiving a kidney transplant. Methods: We retrospectively reviewed the pharmacokinetic data (therapeutic dose, trough level, clearance, and half-life) of 9 children who were given tacrolimus as one of their initial immunosuppressive drugs after kidney transplantation. In addition, we compared the findings to data from 10 adult kidney transplant recipients. Results: The mean age of our pediatric patients was 13.9 years, and the maleto- female ratio was 4:5. The mean dose of tacrolimus was $0.19{\pm}0.14$ mg/kg/day. The mean dose of tacrolimus for males was $0.23{\pm}0.12$ mg/kg/day, which was significantly higher than the dose for females ($0.16{\pm}0.14$ mg/kg/day). The trough level was not significantly different between both groups. The clearance rate of tacrolimus for males was also significantly higher than females. Although the dosage of tacrolimus for patients over the age of 12 years was lower ($0.18{\pm}0.13$ vs. $0.21{\pm}0.16$ mg/kg/day) and the trough level was higher ($8.2{\pm}4.5$ vs. $7.2{\pm}4.2$ mg/mL) than that for patients under the age of 12 years, there was no significant difference between them. However, there were significant differences between children and adults in dose, clearance, and half-life of tacrolimus. Conclusion: Out study suggests that the pharmacokinetics of tacrolimus tends to vary with sex and age. Therefore, large-scale prospective studies are required to verify the proper therapeutic dosage of tacrolimus in Korean children.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.320-325
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• 2009

The present study was carried out to investigate the acute oral toxicity and anti-obesity effects of a diglyceride preparation containing conjugated linoleic acid (DG+CLA). To test its acute oral toxicity, the DG+CLA was injected into 30 rats (15 males and 15 females) at dosage of 2,000 mg/kg and 5,000 mg/kg. Mortality rates, clinical signs, and body weight changes were monitored for 14 days following administration. According to the results, the lethal dose ($LD_50$) of DG+CLA was determined as >5,000 mg/kg in both sexes. There were no significant changes in general conditions, clinical signs, body weight, and gross lesions between the vehicle control and DG+CLA groups. For the anti-obesity studies, obese Zucker rats were randomly divided into 4 groups and fed saline, soybean oil, diglyceride, and DG+CLA, respectively, for 8 weeks. The DG+CLA groups presented significant differences in body weight, food efficiency ratio, serum lipid levels, and fat weight. Overall, the results showed that the DG+CLA did not have acute oral toxicity and reduced body weight, serum lipid levels, and fat gain.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.244-253
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• 2012

The effect of fermented Rhus verniciflua stem bark (FRVSB) extract on the microbial count, enzyme activity, concentrations of free amino acids and organic acids, and physiochemical properties of doenjang (soybean paste) was evaluated during brine fermentation. The FRVSB extract increased the total free amino acid concentration by 1.3-3.1-fold on the $42^{nd}$ day of brine fermentation. After the filtration of brine, the following microbial counts were obtained in the doenjang: bacteria, $0.3{\times}10^8-12.0{\times}10^8$ cfu/g; mold, $3.0{\times}10^4-21.0{\times}10^4$ cfu/g; yeast, $1.0{\times}10^4-2.0{\times}10^4$ cfu/g; Escherichia coli, not detected; and Bacillus cereus, $3.0{\times}10^2-25.0{\times}10^2$ cfu/g. The FRVSB extract addition enhanced the protein and starch degrading activity by 13.8-26.0% and 16.1-35.1%, respectively. The extract increased the total free amino acid content by 1.4-3.0-fold. Lactic acid, acetic acid, and pyroglutamic acid were the predominant organic acids in doenjang. Moreover, the proximate composition, pH, moisture, ash, salt, and amino nitrogen content were increased.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.89-94
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• 2012

Purpose: The option of selecting isotonic rather than hypotonic fluids for maintenance fluid in children has been advocated by some authors. Pneumonia and CNS infections are frequent clinical settings for acute hyponatremia because of nonosmotic anti-diuretic hormone stimuli in children. We conducted the present study to identify the incidence of hyponatremia in pneumonia and CNS infection of children and to determine the importance of maintenance intravenous fluid therapy regimen and other related factors. Methods: The study included 1,992 patients admitted to the Department of Pediatrics at Pusan National University Children's Hospital between November 2008 and August 2011, who were diagnosed with pneumonia or CNS infections and checked for serum sodium concentration. Their clinical data including laboratory findings were reviewed retrospectively. Results: During the study period, 218 patients were identified to have acute hyponatremia among 1,992 patients. The overall incidence of hyponatremia was 10.9%. The incidence of hyponatremia in encephalitis (37.3%) was highest and the incidence in bacterial meningitis (27.4%), viral meningitis (20.0%), bacterial pneumonia (11.1%), mycoplasma pneumonia (9.2%), and viral pneumonia (6.8%) were in descending order. The mean age was higher in hyponatremic patients than in isonatremic patients. The incidence of hyponatremia was higher in who had 0.18% NaCl in 5% dextrose (D5 0.18% NS) than 0.45% NaCl in 5% dextrose infusion (D5 1/2NS) (9.0% vs. 2.2%). SIADH was identified in 20.5% among hospital acquired hyponatremic patients after adequate evaluation for SIADH. Conclusion: We recommend D5 1/2NS rather than D5 0.18% NS as the maintenance fluid given to children with pneumonia or infectious CNS diseases.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.405-415
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• 2000

To determine application rate of elemental sulfur to adjust pH of alkaline soil, buffer curve method was investigated. The elemental sulfur required to control pH 8.3 to pH 6.3 by buffer curve calculation was treated in two soils of silty loam and sandy loam, and the sulfur-mixed soils were moistened with 50% of water holding capacity during incubation of 6 weeks at $30^{\circ}C$. Soil pH was lowered with incubation and reached to target point after 4 weeks of incubation, and elemental sulfur was oxidised entirely to sulfate. This means that buffer curve has the accuracy to determine sulfur application rate in alkaline soil. However it is estimated that application rate of sulfur should be carefully determined in the field scale. Excess application of elemental sulfur resulted in extremely low soil pH and caused the hinderance of lettuce growth by nutritional imbalance and ion toxicity. To simplify the determination procedure of sulfur requirement, buffer curve method by addition of 0.1N-HCl solution as unit of mL was developed, it was compared with theroutine methods which diluted $H_2SO_4$ solution and $Ca(OH)_2$ are added as cmolc per kg soil to adjust each pH step. Buffer capacities, cmolc kg $soil^{-1}$ $pH^{-1}$, calculated from two buffer curves were not significantly different. The result indicates that buffer curve method by 0.1N-HCl can be used to adjust high pH of alkaline soil.