• Tuberculosis and Respiratory Diseases
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• v.53 no.1
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• pp.5-16
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• 2002

Background : Though mononuclear phagocytes serve as the final effectors in killing intracellular Mycobacterium tuberculosis, the bacilli readily survive in the intracellular environment of resting cells. The mechanisms through which cellular activation results in the intracellular killing is unclear. In this study, we sought to explore an in vitro model of a low-level infection of human mononuclear phagocytes with MAC and $H_{37}Ra$ and determine the extent of the lymphocyte dependent cytotoxicity of human monocytes and alveolar macrophages. Materials and Methods : The peripheral monocytes were prepared using the Ficoll gradient method from PPD positive healthy people and tuberculosis patients. The alveolar macrophages were prepared from PPD positive healthy people via a bronchoalveolar lavage. The human mononuclear phagocytes were infected at a low infection rate (bacilli:phagocyte 1:10) with MAC(Mycobacterium avium) and Mycobacterium tuberculosis $H_{37}Ra$. Non-adherent cells(lymphocyte) were added at a 10:1 ratio. After 1,4, and 7 days culture in $37^{\circ}C$, 5% CO2 incubator, the cells were harvested and inoculated in a 7H10/OADC agar plate for the CFU assay. The bacilli were calculated with the CFU/$1{\times}10^6$ of the cells and the cytotoxicity was expressed as the log killing ratio. Results : The intracellular killing of MAC and $H_{37}Ra$ within the monocyte was greater in patients with tuberculosis compared to the PPD positive controls (p<0.05). Intracellular killing of MAC and $H_{37}Ra$ within the alveolar macrophage appeared to be greater than that within the monocytes of the PPD positive controls. There was significant lymphocyte dependent inhibition of intracellular growth of the mycobacteria within the monocytes in both the controls and tuberculosis patients and within the macrophages in the controls(p<0.05). There was no specific difference in the virulence between the MAC and the $H_{37}Ra$. Conclusion : This study is an in vitro model of a low-level infection with MAC and $H_{37}Ra$ of human mononuclear phagocytes. The intracellular cytotoxicity of the mycobacteria within the phagocytic cells was significantly lymphocyte dependent. During the 7 days culture after the intracellular phagocytosis, the actual confinement of the mycobacteria was observed within the monocytes of tuberculosis patients and the alveolar macrophages of the controls as in the case of adding lymphocytes.

• The korean journal of orthodontics
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• v.29 no.6 s.77
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• pp.649-661
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• 1999

The goals of this study were 1) to present pre-surgical naso-alveolar molding (PNAM) appliance for bilateral cleft lip and palate treatment and 2) to evaluate the effects of the PNAM appliance on the alveolar molding of the premaxilla and the lateral segments. Subjects consisted of 8 bilateral cleft lip and palate infants (7 males and 1 female, mean age at first visit = 61.6 days after birth) who were treated with PNAM appliances in Department of Orthodontics, Seoul National University Dental Hospital. Average alveolar cleft gap between the premaxilla and the lateral segment was $8.09{\pm}5.03mm$ and average duration of alveolar molding treatment was $8.8{\pm}3.1$ weeks. These patients' models were obtained at initial visit (T0) and after alveolar molding (T1). 20 linear and 14 angular variables were measured by using photometry and digital caliper, All statistical analyses were performed by Microsoft Excel 97 program. Paired t-test was used to discriminate the effect of alveolar molding by PNAM appliance. 1. Closure of the alveolar cleft gap in bilateral cleft cases by molding therapy was completed successfully, 2. Alveolar molding inhibited outward growth of lateral segments and produced inward bending of lateral segments. 3. By bending the anterior part of the vomer, the premaxilla could be rotated and moved. posteriorly via alveolar molding. Conclusion This appliance can be applied to bilateral cleft lip and palate infants with satisfactory results before cheiloplasty.

• Journal of Genetic Medicine
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• v.4 no.2
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• pp.186-189
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• 2007

More than 6,000 rare disorders including genetic diseases have been reported. Of them, 1,500 diseases (1,211 for clinical diagnosis and 289 for research only) are technically possible for genetic testing. In Korea, since 2005, only 63 genetic diseases is permitted for prenatal genetic testing by the "Bioethics and Biosafety Law". The article 25 in the law prescribes 63 genetic diseases without clear indication for its selection and inclusion criteria. In EU, USA, and other foreign countries, however, there is no provision in the statute on prenatal genetic testing; it is not restricted by a law. Recently, a woman (Mrs. L, 38y) who is a carrier for Menkes disease made an appeal to a government for an amendment of the "Bioethics and Biosafety Law" prohibiting the prenatal diagnosis of her pregnancy at risk for Menkes disease. Menkes disease (MNK) is an X-linked recessive disorder characterized by neurodegeneration, connective tissue defects and hair abnormalities, and no effective treatment is available yet. The prevalence rate of MNK is one in about 250,000 live births. Menkes syndrome patients fail to absorb copper from the gastrointestinal tract in quantities adequate for meeting nutritional needs. These needs seem particularly acute during the initial 12 month of life, when the velocity of brain growth and motor neurodevelopment. Most of pts. die around 3yrs. of age. Mrs. L had a boy with Menkes disease who died at 2y.o. in 2001. Subsequent pregnancy in 2003, she was able to have prenatal genetic testing for mutation of the Menkes (ATP7A) gene and delivered a healthy baby boy. Now, She is pregnant again and wants to have prenatal diagnosis. however, this time, she was not allowed to have any more because Menkes disease is not included in 63 genetic diseases permitted by the law for prenatal genetic testing, in spite of the fact that she is a Menkes disease carrier and her pregnancy is at risk to have an affected baby. This case shows the practical problem of the legal restriction for prenatal genetic testing in Korea. In this study, we report a arguable case and discuss the controversial issues in the legal restriction for prenatal genetic testing in Korea.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.314-324
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• 1997

This study was conducted to investigate whether 1) photosynthetic pigments(chlorophylls and carotenoids) are formed in dodder plant(Cuscuta australis), 2) there are any characteristics in the pigment biosynthesis, compared to that of other normal plants, and 3) dodder responds to some herbicides having target site on chloroplast. 1. Chlorophyll content of dodder tendrill grown under a natural daylight was 9 times and 50 times lower than that of field bindweed stem and leaf, respectively. 2. The photosynthetic pigment contents varied in different tissues, being higher in a apical region than in a lower region of seedling or tendrill. Chlorophyll wasn't almost observed below the 4th internode from the upper. 3. Pigment contents were greatly dependent on light intensity so that there were 4 to 6 times difference among light conditions. When the shoot containning low pigment contents under natural light, was incubated in growth chamber with various light intensities, the pigment contents were increased by 3 times of initial contents at about 97${\mu}E$ $m^{-2}s^{-1}$PAR. While the change in pigment contents was not observed at above 450${\mu}E$ $m^{-2}s^{-1}$PAR 4. Exogenous supply of 5mM 5-aminolevulinic acid increased protochlorophyllide by 7 times and 1.4 times in the etiolated shoot from field bindweed rhizome and in dodder stem, respectively, showing that dodder relatively has a low response to 5-aminolevulinic acid. 5. Pigment loss was observed in the treatment of paraquat, norflurazon, oxyfluorfen and diuron, and protoporphyrin IX was accumulated by oxyfluorfen as in normal plants Based on above results, several chracteristics of pigment biosynthesis in dodder seem to be summerized as follows. Photosynthetic pigment biosynthesis in Cuscuta australis runs even in low level. The pigment contents is differentially distributed in different regions and their contents seem significantly to be controlled by light intensities. Especially, chloroplast rapidly tends to degenerate with the development of tissue. Some herbicides having target site on chloroplast induce damage to dodder stem but are unlikely to control it well in field, except paraquat, due to low chloroplast activity and parasitic mode of nutrition.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.512-520
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• 2001

Kimchi is one of the traditional Korean food and a very popular side dish in Korea. To obtain funda mental data on how to prevent over ripening in kimchi after acidity of 0.4% was reached during the lactate fermentation, the physicochemical characteristics such as pH. acidity. organic acids, enzyme activity were measured and the time dependent ecology of microorganism were observed. In the initial stages of fermentation, the pH of kimchi was markedly changed and slowly decreased in 0.5% acidity The acidity was slowly increased and markedly increased in pH 4 by growth of microorganism. HPLC analysis showed oxalic acid, lactic acid, acetic acid, malic acid and succinic acid and this results reconfirmed by GC-MSD. Lactic acid was changed a lot during fermentation period as the time of storage went on, where as malic was decreased. Kimchi A, having acidity of 0.75%, showed the highest acidic Protease and lipase activity. Also, the amylase activity was high in kimchi C, having 0.95% acidity. The total viable bacteria showed 8.1$\times$10$^{5}$ , 4.7$\times$10$^4$, 1.2$\times$10$^3$, 3.2$\times$10$^4$, 4.9$\times$10$^{5}$ cfu/ml in the kimchi A, B, C, D and E, respectively. The numbers of lactic acid bacteria counted 1.0$\times$10$^{5}$ , 1.3$\times$10s, 1.2$\times$10$^3$, 2.3$\times$ 10$^3$, 2.1$\times$10$^4$c1u/m1 in the kimchi A, B, C, D and E, respectively. The numbers of acetobactor were counted 1.8$\times$10$^{5}$ , 9.3$\times$10$^4$, 7.0$\times$10$^1$, 4.5$\times$10$^4$, 5.3$\times$10$^3$cfu/m1 in the kimchi A, B, C, D and E, respectively.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.121-139
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• 2014

Predicting corporate failure has been an important topic in accounting and finance. The costs associated with bankruptcy are high, so the accuracy of bankruptcy prediction is greatly important for financial institutions. Lots of researchers have dealt with the topic associated with bankruptcy prediction in the past three decades. The current research attempts to use ensemble models for improving the performance of bankruptcy prediction. Ensemble classification is to combine individually trained classifiers in order to gain more accurate prediction than individual models. Ensemble techniques are shown to be very useful for improving the generalization ability of the classifier. Bagging is the most commonly used methods for constructing ensemble classifiers. In bagging, the different training data subsets are randomly drawn with replacement from the original training dataset. Base classifiers are trained on the different bootstrap samples. Instance selection is to select critical instances while deleting and removing irrelevant and harmful instances from the original set. Instance selection and bagging are quite well known in data mining. However, few studies have dealt with the integration of instance selection and bagging. This study proposes an improved bagging ensemble based on instance selection using genetic algorithms (GA) for improving the performance of SVM. GA is an efficient optimization procedure based on the theory of natural selection and evolution. GA uses the idea of survival of the fittest by progressively accepting better solutions to the problems. GA searches by maintaining a population of solutions from which better solutions are created rather than making incremental changes to a single solution to the problem. The initial solution population is generated randomly and evolves into the next generation by genetic operators such as selection, crossover and mutation. The solutions coded by strings are evaluated by the fitness function. The proposed model consists of two phases: GA based Instance Selection and Instance based Bagging. In the first phase, GA is used to select optimal instance subset that is used as input data of bagging model. In this study, the chromosome is encoded as a form of binary string for the instance subset. In this phase, the population size was set to 100 while maximum number of generations was set to 150. We set the crossover rate and mutation rate to 0.7 and 0.1 respectively. We used the prediction accuracy of model as the fitness function of GA. SVM model is trained on training data set using the selected instance subset. The prediction accuracy of SVM model over test data set is used as fitness value in order to avoid overfitting. In the second phase, we used the optimal instance subset selected in the first phase as input data of bagging model. We used SVM model as base classifier for bagging ensemble. The majority voting scheme was used as a combining method in this study. This study applies the proposed model to the bankruptcy prediction problem using a real data set from Korean companies. The research data used in this study contains 1832 externally non-audited firms which filed for bankruptcy (916 cases) and non-bankruptcy (916 cases). Financial ratios categorized as stability, profitability, growth, activity and cash flow were investigated through literature review and basic statistical methods and we selected 8 financial ratios as the final input variables. We separated the whole data into three subsets as training, test and validation data set. In this study, we compared the proposed model with several comparative models including the simple individual SVM model, the simple bagging model and the instance selection based SVM model. The McNemar tests were used to examine whether the proposed model significantly outperforms the other models. The experimental results show that the proposed model outperforms the other models.

• Composites Research
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• v.15 no.4
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• pp.23-31
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• 2002

The two dimensional size effect of specimen gauge section ($length{\;}{\times}{\;}width$) was investigated on the compressive behavior of a T300/924 $\textrm{[}45/-45/0/90\textrm{]}_{3s}$, carbon fiber-epoxy laminate. A modified ICSTM compression test fixture was used together with an anti-buckling device to test 3mm thick specimens with a $30mm{\;}{\times}{\;}30mm,{\;}50mm{\;}{\times}{\;}50mm,{\;}70mm{\;}{\times}{\;}70mm{\;}and{\;}90mm{\;}{\times}{\;}90mm$ gauge length by width section. In all cases failure was sudden and occurred mainly within the gauge length. Post failure examination suggests that $0^{\circ}$ fiber microbuckling is the critical damage mechanism that causes final failure. This is the matrix dominated failure mode and its triggering depends very much on initial fiber waviness. It is suggested that manufacturing process and quality may play a significant role in determining the compressive strength. When the anti-buckling device was used on specimens, it was showed that the compressive strength with the device was slightly greater than that without the device due to surface friction between the specimen and the device by pretoque in bolts of the device. In the analysis result on influence of the anti-buckling device using the finite element method, it was found that the compressive strength with the anti-buckling device by loaded bolts was about 7% higher than actual compressive strength. Additionally, compressive tests on specimen with an open hole were performed. The local stress concentration arising from the hole dominates the strength of the laminate rather than the stresses in the bulk of the material. It is observed that the remote failure stress decreases with increasing hole size and specimen width but is generally well above the value one might predict from the elastic stress concentration factor. This suggests that the material is not ideally brittle and some stress relief occurs around the hole. X-ray radiography reveals that damage in the form of fiber microbuckling and delamination initiates at the edge of the hole at approximately 80% of the failure load and extends stably under increasing load before becoming unstable at a critical length of 2-3mm (depends on specimen geometry). This damage growth and failure are analysed by a linear cohesive zone model. Using the independently measured laminate parameters of unnotched compressive strength and in-plane fracture toughness the model predicts successfully the notched strength as a function of hole size and width.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.425-430
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• 2005

[${\beta}-sitosterol$] is a plant sterol that reduces cholesterol levels and inhibits the growth of human prostate and colon cancer cells. Optimal conditions for ${\beta}-sitosterol$ production were examined from cell suspension cultures of Chrysanthemum coronarium L. The callus induction was optimal in MS medium containing 1 mg/l NAA and 1 mg/l BAP. Cell suspension culture was also established from the callus. Optimal ${\beta}-sitosterol$ production was obtained when the cells were cultured at an initial density of 2 mg DCW/l in MS medium containing 1 X sucrose (30 mg/l), 1 X nitrogen (1900 mg/l $KNO_3$, 1650 mg/l $NH_4NO_3$), and 1 X phosphate source (170 mg/l). In cell suspension cultures of C. coronarium L. using shake flasks, the peak content of ${\beta}-sitosterol$ was $150{\mu}g/g$ DCW. In cell suspension cultures of C. coronarium L. using an air-lift bioreactor, the maximum ${\beta}-sitosterol$ content of $143.8{\mu}g/g$ DCW was obtained at an air-flow rate of 100 cc/min.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.539-544
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• 2005

Purpose : The aim of this study was to investigate the pathophysiologic role of serum E-selectin, vascular endothelial growth factor(VEGF)-induced cell adhesion mollecule in Kawasaki disease(KD) and to look for the evidence of direct relationship between the plasma levels of soluble E-selectin and the incidence of coronary artery lesion(CAL). Methods : Changes in plasma levels of sE-selectin(n=98) over time were measured by enzyme-linked immunosorbent assay(ELISA) in 23 patients with acute KD and 25 age-matched febrile children. Results : Compared with control values, the peak levels of plasma sE-selectin were significantly elevated($mean{\pm}S.E$. : $22.89{\pm}12.53ng/mL$ vs $10.65{\pm}3.42ng/mL$, P=0.01) in KD. 5 patients with CAL, plasma sE-selectin levels before treatment were higher than in 18 patients without CAL($mean{\pm}S.E$. : $39.43{\pm}15.08ng/mL$ and $19.00{\pm}8.32ng/mL$, respectively; P=0.01). Plasma sE-selectin declined rapidly in the majority of KD patients regardless of the presence of CAL. Plasma sE-selectin levels after treatment and convalesent period were similar in KD patients with and without CAL. The plasma levels sE-selectin were correlated with those of white blood cell count(r=0.299, P<0.05), CRP(r=0.430, P<0.05), serum albumin(r=-0.483, P<0.05), serum protein(r=-0.502, P<0.05) and hemoglobin(r=-0.372, P<0.05) not with those of ESR, platelet, or duration of fever. There were significant differences in the initial level of serum sE-selectin between KD with and without CAL($mean{\pm}S.E$. : $39.44{\pm}15.08ng/mL$ vs. $19.00{\pm}17.18ng/mL$) in multivariated linear tests. Conclusion : Plasma sE-selectin levels were significantly higher in KD than in other febrile illness. Higher plamsa levels of sE-selectin may have potential as a predictor of CAL in patients with KD.

• Magazine of the Korean Society of Agricultural Engineers
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• v.10 no.1
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• pp.1388-1393
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• 1968

Higher yield in rice paddies is greatly dependent on adequately balanced and timely supply of water. A majority of rice paddy in Korea is generally irrigated by rainfall, but in many cases it has to be supplemented by artificial irrigation for optimum rice culture. Although the water requirement of rice plant is far higher than that of other crops, submerged condition of rice paddy is not necessarily required. The moisture requirement of rice plant varies with its growing stages, and it is possible to increase the irrigation efficiency through reduction of water loss due to percolation in rice paddies. An experiment was conducted on the effectiveness of economical use of water by different irrigation period and different method of cultivation. The experimental plots were set up by means of randomized block design with three duplications; (a) Alltime submerged (b) Economically controlled, and (c) Extremely controlled. Three different irrigation periods were (a) Initial stage (b) Inter-stage, and (c) last stage. The topsoil of the three plots were excavated to the depth of 30cm and then compacted with clay of 6 cm thickness. Thereafter, they were piled up with the excavated top soils, leveled and cored with clay of 6cm thickeness arround footpath in order to prevent leakage. The results obtained frome the experiments are as follows; (1) There is no difference among the three experiment plots in terms of physical and chemical contditions, soil properties, and other characteristics. (2) Colulm length and ear length are not affected by different irrigation methdos. (3) There is no difference in the mature rate and grain weight of rice for the three plots. (4) The control plot which was irrigated every three days shows an increased yield over the all the time submerged plot by 17 persent. (5) The clay lined plot whose water holding capacity was held days long, needs only to be irrigated every 7 days. (6) The clay lined plot showes an increased yield over the untreated plot; over all the time submerged plot by 18 percent, extremely controlled plot by 18 percent, and economically controled plot by 33 percent.