• Radiation Oncology Journal
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• v.27 no.1
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• pp.42-48
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• 2009

Purpose: The introduction of image guided radiation therapy/four-dimensional radiation therapy (IGRT/4DRT) potentially increases the accumulated dose to patients from imaging and verification processes as compared to conventional practice. It is therefore essential to investigate the level of the imaging dose to patients when IGRT/4DRT devices are installed. The imaging dose level was monitored and was compared with the use of pre-IGRT practice. Materials and Methods: A four-dimensional CT (4DCT) unit (GE, Ultra Light Speed 16), a simulator (Varian Acuity) and Varian IX unit with an on-board imager (OBI) and cone beam CT (CBCT) were installed. The surface doses to a RANDO phantom (The Phantom Laboratory, Salem, NY USA) were measured with the newly installed devices and with pre-existing devices including a single slice CT scanner (GE, Light Speed), a simulator (Varian Ximatron) and L-gram linear accelerator (Varian, 2100C Linac). The surface doses were measured using thermo luminescent dosimeters (TLDs) at eight sites-the brain, eye, thyroid, chest, abdomen, ovary, prostate and pelvis. Results: Compared to imaging with the use of single slice non-gated CT, the use of 4DCT imaging increased the dose to the chest and abdomen approximately ten-fold ($1.74{\pm}0.34$ cGy versus $23.23{\pm}3.67$cGy). Imaging doses with the use of the Acuity simulator were smaller than doses with the use of the Ximatron simulator, which were $0.91{\pm}0.89$ cGy versus $6.77{\pm}3.56$ cGy, respectively. The dose with the use of the electronic portal imaging device (EPID; Varian IX unit) was approximately 50% of the dose with the use of the L-gram linear accelerator ($1.83{\pm}0.36$ cGy versus $3.80{\pm}1.67$ cGy). The dose from the OBI for fluoroscopy and low-dose mode CBCT were $0.97{\pm}0.34$ cGy and $2.3{\pm}0.67$ cGy, respectively. Conclusion: The use of 4DCT is the major source of an increase of the radiation (imaging) dose to patients. OBI and CBCT doses were small, but the accumulated dose associated with everyday verification need to be considered.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.12-18
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• 2006

Thirty five Salmonella enterica serovar Typhimurium strains were isolated from diarrheic patients and pigs in Gyeongbuk area from 2003 to 2004. All 35 strains (17 strains from diarrheic patients and 18 from pigs) were resistant to more than one drug and most of strains isolated from pigs were resistant to ampicillin, ohloram-phenicol, streptomycin, sulfamethoxazole-trimethoprime, tetracyclin and nalidixic acid. Each isolate was also screened or the presence of class I, II and III integron gene cassettes. Among 35 strains,3 out of 17 strains isolated from diarrheic patients, carried dhfrX-orfF-aadA2 integron gene cassette and among 18 strains isolated from diseased pigs, 11 strains carried dhfrX-orfF-aadA2 integron gene cassette and 1 strain carried aadA2 integron only. But any class II and class II integron gene cassette were not detected in 35 strains. Thirty five strains were divided by five pulsotypes. Thirty one strains out of thirty five were pulsotype A. Among the remaining 4 strains, one each strain belonged to pulsotype B, C, D and pulsotype E. This data of pulsotypes showed that the widespread of pulsotype A, Salmonella enterica serovar Typhimurium in human and pigs in Gyeongbuk area may have been caused by the dissemination of a few epidemic strains in this area. Thirteen strains contain dhfrX-orfF-aadA2 integron gene cassette showed pulsotype A and one strain contains dhfrX-orfF-aadA2 integron gene cassette showed pulsotype B. One strain contains aadA2 integron showed pulsotype E. But fifteen strains do not contain any integron showed pulsotype A.

• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.397-406
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• 2015

ZnO, II-VI group inorganic compound semi-conductor, has been receiving much attention due to its wide applications in various fields. Since the ZnO has 3.37 eV of a wide band gap and 60 meV of big excitation binding energy, it is well-known material for various uses such the optical property, a semi-conductor, magnetism, antibiosis, photocatalyst, etc. When applied in the field of photocatalyst, many research studies have been actively conducted regarding magnetic materials and the core-shell structure to take on the need of recycling used materials. In this paper, magnetic core-shell ZnFe₂O₄@SiO₂ nanoparticles (NPs) have been successfully synthesized through three steps. In order to analyze the structural characteristics of the synthesized substances, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR) were used. The spinel structure of ZnFe₂O₄ and the wurtzite structure of ZnO were confirmed by XRD, and ZnO production rate was confirmed through the analysis of different concentrations of the precursors. The surface change of the synthesized materials was confirmed by SEM. The formation of SiO₂ layer and the synthesis of ZnFe₂O₄@ZnO@SiO₂ NPs were finally verified through the bond of Fe-O, Zn-O and Si-O-Si by FT-IR. The magnetic property of the synthesized materials was analyzed through the vibrating sample magnetometer (VSM). The increase and decrease in the magnetism were respectively confirmed by the results of the formed ZnO and SiO₂ layer. The photocatalysis effect of the synthesized ZnFe₂O₄ @ZnO@SiO₂ NPs was experimented in a black box (dark room) using methylene blue (MB) under UV irradiation.

• Journal of Korean Home Economics Education Association
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• v.29 no.4
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• pp.117-131
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• 2017

This study was performed to analyze education contents related to milk in current home economics textbooks of middle school, and to investigate intake status, consumption behaviors, perception and nutritional knowledge of milk and dairy products among 364 middle school students in Gongju for improvement of milk education in home economics subjects and milk intake of adolescents. As a result, education contents of milk and dairy products in home economics textbooks currently applied in middle school were major nutrients, consumption method for balanced diet, and selection and storage of milk and dairy products, thus it tended not to match current food trend. Only 30.5% of subjects met 2 cups of milk a day, the recommended level. The main reason for drinking milk was to 'be taller' and 'to quench thirst' and there was a difference by gender(p<0.01). The rate of not participating in school milk program was 23.1% of total and its satisfaction was moderate. The most popular dairy products by subjects were ice cream, followed by yogurt and cheese, and the choice of milk was focused on 'taste' or 'expiration date'. The rate of knowing certification mark of K-MILK was low at 28.8%, and most subjects knew as 'domestic milk use'. In home economics class, experience-based learning such as cow ranch experience was the most preferred instruction method for milk followed by laboratory practice and lecture, and there was a difference by gender(p<0.001). Perception degree of milk and dairy products was moderate and male subjects were more positively perceived than female subjects(p<0.01). Nutritional knowledge level of milk and dairy products was moderate and female subjects were higher than male subjects(p<0.01). Therefore, education contents of milk and dairy products of home economics textbooks of middle school should be centered on real life in accordance with food trend, and applied student participation-based instruction methods such as experience-based learning. In addition, it is necessary to enhance taste and merchandise of milk and to provide them with preferred milk and dairy products in school milk program for improvement of milk intake of adolescents.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.606-612
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• 2005

Background : It has been reported that nontuberculosis mycobacterium(NTM) isolates account for approximately 10% of patients with a positive Acid-Fast Bacilli(AFB) smear. Therefore, it is necessary to consider NTM pulmonary disease when such a positive test is encountered. The aim of this study was to evaluate the etiologies and clinical characteristics of patients with NTM pulmonary disease who had been treated at a national tuberculosis hospital. Methods : The NTM isolates were recovered from the sputum or bronchial washing specimens submitted to a clinical laboratory of National Masan TB Hospital from August 2002 to July 2003. All samples were identified using a polymerase chain reaction-restriction fragment length polymorphism analysis method, which amplifies the rpoB gene. The patients were diagnosed with NTM disease according to the American Thoracic Society diagnostic criteria. Results : One hundred NTM isolates were recovered from 57 patients. Of the 100 isolates, M. avium complex(MAC) was the most common species, which was found 55%(n=55) of patients, followed by M. abscessus(n=25), and M. fortuitum( n=9). 26(45.6%) patients had NTM disease. Twenty-six (45.6%) patients had NTM disease according to The American Thoracic Society classification. The main organisms involved in NTM disease were MAC(n=19, 73.1%) and M. abscessus(n=5, 19.2%). The pathogenic potential was 67.9% in M. intracellulare and 41.7% in M. abscessus. The predictive factors related to NTM disease were a positive sputum smear (OR 6.4, p=0.02) and the isolation of either MAC or M. abscessus(OR 6.9, p=0.007). Fifteen patients(57.7%) were cured. There were no significant factors associated with the treatment success. Conclusion : There was a relatively high proportion of NTM disease in NTM isolates and the common species were MAC and M. abscessus. The predictive factors for NTM disease were a positive sputum smear and the isolation of either MAC or M. abscessus.

• Tuberculosis and Respiratory Diseases
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• v.71 no.2
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• pp.120-125
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• 2011

Background: Although the prevalence of pulmonary tuberculosis has progressively decreased all over the world, drug-resistant tuberculosis is major obstacle in treating tuberculosis. This study was performed to examine the current prevalence and risk factors of drug resistant tuberculosis in a single tertiary hospital in Busan, Korea. Methods: We enrolled 367 patients with active pulmonary tuberculosis on a retrospective basis who had undergone mycobacterium culture and drug sensitivity tests between January 2005 and December 2009. We analyzed all clinical and radiographic parameters to find predictors related to drug resistant tuberculosis. Results: At least one incident of drug resistance was found in 75 (20.4%) patients. Isoniazid (18.8%) was the most frequent resistant drug, followed by rifampin (10.9%), ethambutol (7.1%), streptomycin (4.9%), and fluoroquinolone (2.7%). Resistance to second-line drugs was found in 37 (10.1%) patients. Multidrug resistance and extensively drug resistance was evident in 39 (10.6%) and 4 (1.1%) patients, respectively. Using multiple logistic regression analysis, history of previous treatment including relapse (odd ratio [OR], 11.3; 95% confidence interval [CI], 4.92~26.08; p<0.01), treatment failure (OR, 24.1; 95% CI, 5.65~102.79; p<0.01) and an age of below 46 years-old (OR, 3.8; 95% CI, 1.62~8.65; p<0.01) were found to be independent predictors of multidrug resistant tuberculosis. Conclusion: We found that the prevalence of drug resistant tuberculosis was considerably high. A careful consideration for possible drug resistant tuberculosis is warranted in patients with a history of previous treatment or for younger patients.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.243-264
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• 2018

Although the worldwide battery market is recently spurring the development of lithium secondary battery, lead acid batteries (rechargeable batteries) which have good-performance and can be reused are consumed in a wide range of industry fields. However, lead-acid batteries have a serious problem in that deterioration of a battery makes progress quickly in the presence of that degradation of only one cell among several cells which is packed in a battery begins. To overcome this problem, previous researches have attempted to identify the mechanism of deterioration of a battery in many ways. However, most of previous researches have used data obtained in a laboratory to analyze the mechanism of deterioration of a battery but not used data obtained in a real world. The usage of real data can increase the feasibility and the applicability of the findings of a research. Therefore, this study aims to develop a model which predicts the battery deterioration using data obtained in real world. To this end, we collected data which presents change of battery state by attaching sensors enabling to monitor the battery condition in real time to dozens of golf carts operated in the real golf field. As a result, total 16,883 samples were obtained. And then, we developed a model which predicts a precursor phenomenon representing deterioration of a battery by analyzing the data collected from the sensors using machine learning techniques. As initial independent variables, we used 1) inbound time of a cart, 2) outbound time of a cart, 3) duration(from outbound time to charge time), 4) charge amount, 5) used amount, 6) charge efficiency, 7) lowest temperature of battery cell 1 to 6, 8) lowest voltage of battery cell 1 to 6, 9) highest voltage of battery cell 1 to 6, 10) voltage of battery cell 1 to 6 at the beginning of operation, 11) voltage of battery cell 1 to 6 at the end of charge, 12) used amount of battery cell 1 to 6 during operation, 13) used amount of battery during operation(Max-Min), 14) duration of battery use, and 15) highest current during operation. Since the values of the independent variables, lowest temperature of battery cell 1 to 6, lowest voltage of battery cell 1 to 6, highest voltage of battery cell 1 to 6, voltage of battery cell 1 to 6 at the beginning of operation, voltage of battery cell 1 to 6 at the end of charge, and used amount of battery cell 1 to 6 during operation are similar to that of each battery cell, we conducted principal component analysis using verimax orthogonal rotation in order to mitigate the multiple collinearity problem. According to the results, we made new variables by averaging the values of independent variables clustered together, and used them as final independent variables instead of origin variables, thereby reducing the dimension. We used decision tree, logistic regression, Bayesian network as algorithms for building prediction models. And also, we built prediction models using the bagging of each of them, the boosting of each of them, and RandomForest. Experimental results show that the prediction model using the bagging of decision tree yields the best accuracy of 89.3923%. This study has some limitations in that the additional variables which affect the deterioration of battery such as weather (temperature, humidity) and driving habits, did not considered, therefore, we would like to consider the them in the future research. However, the battery deterioration prediction model proposed in the present study is expected to enable effective and efficient management of battery used in the real filed by dramatically and to reduce the cost caused by not detecting battery deterioration accordingly.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.537-545
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• 1994

Background: In 1987, the British Thoracic Society (BTS) subjected an extensive list of patient variables to statistical analysis in a prospective study of prognosis in 453 adults with community-acquired pneumonia and, subsequently published guidelines for management of severe community acquired pneumonia. It was hoped that those at risk of dying from community acquired pneumonia could be easily identified and treated appropriately, thereby reducing mortality. To date, severe community acquired pneumonia has not been well studied in Korea. Therefore, we studied retrospectively 10 patients dying of severe community acquired pneumonia in Dongsan Hospital to see clinical manifestations of dying of severe community-acquired pneumonia. Methods: Between July 1987 and july 1993, 498 patients were admitted to Keimyung University Dongsan Hospital with community acquired pneumonia, and 77 of them received intensive care. Of the 77 patients, 10 patients died. We reviewed medical records of these patients. Results: 1) The mean age of the patients was 56.2 years(range, 25 to 75 years). There were 7 men and 3 women. Seven patients(70%) were older than 60years of age. 2) The clinical features on admission were as follows: tachypnca, hypoxemia, mental change, cyanosis, leukopenia, leukocytosis, azotemia, hypotension, hypoalbuminemia in order of frequency. Three patients had one abnormal physical finding, 3 patients had 2, 2 patients had 3, and 2 patients had none of these abnormal physical findings. All patients had at least one of the abnormal laboratory findings. 3) A potential bacterial pathogen was isolated in sputum culture from 2 patients. One was E.coli, the other Enterobacter species. Sputum stain were positive in eight cases (G(+)cocci in six, G(+) cocci and G(-)bacilli in two). 4) Features of respiratory failure were the main reasons for ICU transfer, but two patients were transferred only following a cardiac or respiratory arrest in the general ward. 5) The mean of 2.7 different antibiotics were given to the patients. The aminoglycoside and first generation cephalosporin were the most frequently prescribed antibiotics, followed by the third generation cephalosporin and vancomycin. The most frequently prescribed antibiotics combination was a 1st generation cephalosporin plus an aminoglycoside. 6) Seven patients death(70%) occured after admission within the first five days, and a mean duration of hospitaliztion was 11.2 days. Conclusion: As the results show most death occured within the first five days after admission and aged patients; consequently, an aggressive intensive treatment should be provided early to the patients with severe community acquired pneumonia, and we should pay more attention to the aged patients.

• Tuberculosis and Respiratory Diseases
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• v.48 no.5
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• pp.773-780
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• 2000

Background : pH measurement is an important test in assessing the etiology of pleurisy and in identifying complicated parapneumonic effusion. Although the blood gas analyzer is the gold standard method' for pleural pH measurement, pH meter & pH strip methods are also used for this purpose interchangably. However, the correlation among the pH data measured by the three different methods needs to be evaluated. In this study, we measured the pH of pleural fluid with the three different methods respectively and evaluated the correlation among the measured data. Methods : From August 1999 to March 2000, we measured the pleural fluid pH in 34 clinical samples with three methods-blood gas analyzer, pH meter, and pH strip. In the blood gas analyzer and pH meter methods, the temperature of pleural fluid was maintained around $0^{\circ}C$ in air-tight condition before analysis and measurement was performed within 30 minutes after collection. As for the pH strip method, the pleural fluid pH was checked in the ward immediately after tapping and in the clinical laboratory of our hospital. This part is unclear. Results : The causes of pleural effusion were tuberculosis pleurisy in 16 cases, malignant pleural effusion 5 cases, parapneumonic effusion 9 cases, empyema 3 cases, and congestive heart failure 1 case. The pH of pleural fluid (mean$\pm$SD) was 7.34$\pm$0.12 with blood gas analyser, 7.52$\pm$0.25 with pH meter, 7.37$\pm$0.16 with pH strip of immediate measurement and 6.93$\pm$0.201 with pH strip of delayed measurement. The pH measured by delayed pH strip measurement was lower than those of other methods (p<0.05). The correlation of the results between the blood gas analyzer and pH meter(p=0.002, r=0.518) and the blood gas analyzer and pH strip of immediate measurement(p<0.001, r=0.607). Conclusion : In the determination of pH of pleural fluid, pH strip method could be a simple and reliable method under immediate measurement conditions after pleural fluid tapping.

• Clinical and Experimental Pediatrics
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• v.53 no.1
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• pp.28-32
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• 2010

Purpose : Although eosinophilia is a common laboratory finding in many neonatal intensive care units (ICUs), its causative mechanisms remain obscure. We aimed to determine the causes of eosinophilia in the neonatal ICU environment. Methods : Serial eosinophil counts were determined weekly for 288 hospitalized, appropriately grown neonates. Infants were divided into four groups according to gestational age, and the incidence and etiologic factors of eosinophilia were retrospectively studied. Results : Absolute eosinophilia (>$700/mm^3$) was documented in 18% (52/288) of neonates. Twenty-two infants (42.3%) exhibited mild eosinophilia ($700-999cells/mm^3$), 27 (51.9%) exhibited moderate eosinophilia ($1,000-2,999cells/mm^3$), and 3 (5.8%) exhibited severe eosinophilia (>$3,000cells/mm^3$). Of the 288 infants studied, 54 suffered sepsis. Thirty of these 54 infants (55.6%) showed eosinophilia, and 22 out of the remaining 234 infants (9%) without sepsis showed eosinophilia, indicating that eosinophilia was more prevalent in the sepsis group (P <0.05). All 5 infants suffering from bronchopulmonary dysplasia showed eosinophilia, and 47 out of the remaining 283 infants (16.7%) without bronchopulmonary dysplasia showed eosinophilia. Thus, eosinophilia was more prevalent in the bronchopulmonary dysplasia group (P<0.05). Furthermore, increased prevalence of eosinophilia was associated with respiratory distress syndrome, ventilator use, blood transfusion, and total parenteral nutrition (P<0.05). Conclusion : Our results suggest that eosinophilia is influenced by sepsis and bronchopulmonary dysplasia, although it can also occur idiopathically at birth. Moreover, the potential role of eosinophils in conditions such as wound healing and fibrosis in sepsis or chronic lung disease may be a cause of eosinophilia.