• Journal of dental hygiene science
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• v.17 no.6
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• pp.487-494
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• 2017

There is little evidence on the effects of environmental tobacco smoke (ETS) on prevalence of periodontal disease. The aims of this study were to explore the trends of prevalence of periodontal disease and types of exposure to smoke, including ETS according to the survey year, identify factors affecting periodontal disease, and compare the effect size of periodontal disease between active smokers and secondhand smokers. Data on 11,643 individuals were obtained from the fourth and fifth Korean National Health and Nutritional Examination Surveys. Information on exposure to ETS at home and work was self-reported. Severity of periodontal disease was evaluated using the community periodontal index. A multivariate logistic regression analysis was performed to model periodontal disease using types of smoking and the survey year. Overall, the prevalence of periodontal disease was 26.0% (n=3,029) and about 9% of the study population were secondhand smokers. The prevalence of periodontal disease among smokers was significantly increased according to smoking types by year. Active smokers showed a statistically significant adjusted odds ratio (aOR) for having periodontal disease except in the year 2007, whereas secondhand smokers had significant associations only in 2010 (aOR, 1.68; 95% confidence interval, 1.05 to 2.70) compared to non-smokers. For secondhand smokers, the statistical relationship of predicting periodontal disease was weaker than that of active smokers. However, ETS should separately be considered as an important risk factor for periodontal disease. This study suggested the need for further investigation of the impact of ETS on prevalence of periodontal disease using in-depth research designs and objective measurements for assessing periodontal disease and ETS.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.213-221
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• 2008

Purpose: The objective of this retrospective study was to identify predictive factors for the complete pathologic response and tumor downstaging after preoperative concurrent chemoradiotherapy for locally advanced rectal cancer. Materials and Methods: Between the years 2000 and 2008, 39 patients with newly diagnosed rectal cancer without prior evidence of distant metastasis received preoperative concurrent chemoradiotherapy followed by surgery. The median radiation dose was 50.4 Gy (range, $45{\sim}59.4\;Gy$)). Thirty-eight patients received concurrent infusional 5-fluorouracil and leucovorin, while one patient received oral capecitabine twice daily during radiotherapy. Results: A complete pathologic response (CR) was demonstrated in 12 of 39 patients (31%), while T-downstaging was observed in 24 of 39 patients (63%). N-downstaging was observed in 18 of 28 patients (64%), with a positive node in the CT scan or ultrasound. Two patients with clinical negative nodes were observed in surgical specimens. The results from a univariate analysis indicated that the tumor circumferential extent was less than 50% (p=0.031). Moreover, the length of the tumor was less than 5 cm (p=0.004), while the post-treatment carcinoembryonic antigen (CEA) levels were less than or equal to 3.0 ng/mL (p=0.015) and were significantly associated with high pathologic CR rates. The univariate analysis also indicated that the adenocarcinoma (p=0.045) and radiation dose greater than or equal to 50 Gy (p=0.021) were significantly associated with high T-downstaging, while a radiotherapy duration of less than or equal to 42 days (p=0.018) was significantly associated with N-downstaging. The results from the multivariate analysis indicated that the lesser circumferential extent of the tumor (hazard ratio [HR] 0.150; p=0.028) and shorter tumor length (HR, 0.084; p=0.005) independently predicted a higher pathologic CR. The multivariate analysis also indicated that a higher radiation dose was significantly associated with higher T-downstaging (HR, 0.115; p=0.025), while the shorter duration of radiotherapy was significantly associated with higher N-downstaging (HR, 0.028; p=0.010). Conclusion: The circumferential extent of the tumor and its length was a predictor for the pathologic CR, while radiation dose and duration of radiotherapy were predictors for tumor downstaging. Hence, these factors may be used to predict outcomes for patients and to develop further treatment guidelines for high-risk patients.

• Clinical and Experimental Pediatrics
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• v.53 no.3
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• pp.364-372
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• 2010

Purpose : Good adherence of caregivers is essential for successful health outcomes in the treatment of childhood asthma. The purpose of this study was to identify the factors contributing to good adherence of maintenance treatment in children with well-controlled asthma. Methods : Children with well-controlled asthma being treated with a daily controller for at least 3 months in Korea University Anam Hospital were selected. Their caregivers who had good adherence to maintenance treatment were recruited. Qualitative study through in-depth interviews was conducted with 18 caregivers who agreed to the study. Results : The 18 caregivers (mean age, 40.0 years) consisted of 15 mothers, 2 grandmothers, and 1 father. The resulting consensus were identified and grouped into 2 domains: the caregiver/patient aspect with 8 theme factors and the treatment aspect with 4 theme factors. The main theme factors in the caregiver/patient aspect were enabling participation in physical activities and exercise (77.8%), perceptions regarding asthma and the need for long-term treatment (50.0%), and perceived value of the medications outweighing the risk of side effects (38.9%). The main theme factors in the treatment aspect were trust in the physician (77.8%), general satisfaction with the manner and attitude of the physician (77.8%) and verification of the necessity of further treatment by performing tests (38.9%). Conclusion : Efforts to improve caregivers' adherence to the treatment of childhood asthma must include a range of factors related to both caregiver/patient aspects and treatment aspects. Among all of these factors, it may be most important to establish a physician-caregiver partnership.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.169-178
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• 2000

Background : Usually fever subsides within one week in over 90% of pulmonary tuberculosis (TBp) patients after the start of short-course anti-tuberculosis therapy, but occasionally it persists over two weeks after treatment. When the fever persists, drug resistance, combined infection, or drug fever, and so on, are considered as an etiology and, in some cases, drugs are changed. But inadvertent discontinuation of a short-course regimen inevitably will extend the duration of treatment, and the treatment completion may be delayed. This study was performed to investigate the causes of prolonged fever (PF) and to identify the predictors of PF in drug-susceptible TBp patients in Korea. Method : Five hundred-ninety-eight patients, who were admitted to Asan Medical Center from January 1996 to March 1999, diagnosed with TBp and prescribed short-course, anti-tuberculosis treatment, were reviewed. PF was defined as having fever over two weeks despite treatment. The causes of PF were analyzed. Drug-sus-ceptible TBp patients who presented no causes for PF, except turberculosis itself, were selected(n=22), and they were compared with those who had no fever at diagnosis (n=22) and those who had fever at diagnosis, which had subsided within two weeks after treatment (n=22). Clinical, laboratory, and radiological parameters were compared among the three groups. Results : Twenty-eight (4.8%) of 598 patients showed PF over two weeks despite short-course treatment. The causes of PF were drug fever (n=2), multi-drug resistant tuberculosis (n=3), disseminated Mycobacterium kansasii infection (n=1), and drug-susceptible tuberculosis itself (n=22). The patients with PF had more risk factors for tuberculosis, long duration of symptoms before treatment, night sweats, weight long, numerous acid fast bacilli on sputum smear, anemia, hyponatremia, hypoalbuminemia, over three lung cavity numbers and extensive infiltration, indicating that they had prolonged and extensive lung diseases. Conclusion : The main cause of PF in TBp despite short-course regimen seems to be drug-susceptible but extensive disease in Korea. Any changes to the drug regiment provided for TBp patients with prolonged fever despite treatment should be carefully considered.

• Tuberculosis and Respiratory Diseases
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• v.55 no.4
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• pp.353-360
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• 2003

Background : Although most patients with tuberculous pleurisy respond well to anti-tuberculous drugs, some are known to progress into severe pleural thickening which needs decortication despite adequate anti-tuberculous treatment. Therefore, the purpose of this study was to identify factors associated with the development of severe pleural thickening in patients who finally underwent pleural decortication in tuberculous pleurisy. Patients and Methods : From retrospective medical records review, 121 patients initially diagnosed as tuberculous pleurisy without initial pleural fluid loculation were enrolled between January 1998 and December 2002. They were separated into two groups: 85 patients in group 1 who improved by anti-tuberculous drugs only, and 36 patients in group 2 who had progressed into pleural adhesion and finally underwent pleural decortication despite adequate (more than 6 months) anti-tuberculous treatment. Results : Males were more common in group 2 (M/F=31/5) than in group 1 (M/F=53/32) (p=0.010). Group 2 patients tended to have lower pleural fluid glucose level ($58{\pm}4$ mg/dL) than group 1 ($89{\pm}3$ mg/dL) (p=0.001) and higher pleural fluid adenosine deaminase level ($86{\pm}5$ IU/L) than group 1 ($76{\pm}3$ IU/L), (p=0.038). There were no significant differences in age, symptom duration, pleural fluid amount, or pleural fluid LDH level between groups 1 and 2. Conclusions : There was a relative risk of tuberculous pleurisy progression into severe pleural thickening which needed decortication in the case of male patients, low pleural fluid glucose or high adenosine deaminase level. But further, large-scale, prospective studies should be investigated.

• Genomics & Informatics
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• v.9 no.2
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• pp.52-58
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• 2011

Osteoporotic fracture (OF), along with bone mineral density (BMD), is an important diagnostic parameter and a clinical predictive risk factor in the assessment of osteoporosis in the elderly population. However, a genome-wide association study (GWAS) on OF has not yet been clarified sufficiently. To identify OF-associated genetic variants and candidate genes, we conducted a GWAS in a population-based cohort (Korean Association Resource [KARE], n=1,427 [case: 288 and control: 1139]) and performed a de novo replication study in hospital-based individuals (Asan and Catholic Medical Center [ACMC], n=1,082 [case: 272 and control: 810]). In a combined meta-analysis, a newly identified genetic locus in an intergenic region at 10p11.2 (near genes FZD8 and ANKRD30A ) showed the most significant association (odd ratio [OR] = 2.00, 95% confidence interval [CI] = 1.47~2.74, p=$1.27{\times}10^{-6}$) in the same direction. We provide the first evidence for a common genetic variant influencing OF and genetic information for further investigation in bone metabolism.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.3
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• pp.281-293
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• 2020

Recently, large and small fires have been happening more often in Korea. Fire is one of the most frequent disasters along with traffic accidents in korean cities, and this frequency is closely related to the land use and the type of facilities. Therefore, in this study, the significance of fires was analyzed by considering land use, facility types, human and social factors and using 10 years of fire data in Jinju city. Based on this, OLS (Ordinary Least Square) regression analysis, SLM (Spatial Lag Model) and SEM (Spatial Error Model) using space weights, were compared and analyzed considering the location of the fire and each factor, then a statistical model with high suitability was presented. As a result, LISA analysis of spatial distribution patterns of fires in Jinju city was conducted, and it was proved that the frequency of fires was high in the order as follow, central commercial area, industrial area and residential area. Multiple regression analysis was performed by integrating demographic, social, and physical variables. Therefore, the three models were compared and analyzed by applying spatial weighting to the derived factors. As a result of the significance test, the spatial error model was analyzed to be the most significant. The facilities that have the highest correlation with fire occurrence were second type neighborhood facilities, followed by detached house, first type neighborhood facilities, number of households, and sales facilities. The results of this study are expected to be used as significant data to identify factors and manage fire safety in urban areas. Also, through the analysis of the standard deviation ellipsoid, the distribution characteristics of each facility in the residential area, industrial area, and central commercial area among the use areas were analyzed. In, the second type neighborhood facility with the highest fire risk was concentrated in the center. The results of these studies are expected to be used as useful data for identifying factors and managing fire safety in urban areas.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.169-175
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• 2018

This study deals with a process for the recovery of hydrogen isotopes from methane ($CQ_4$) and water ($Q_2O$) containing tritium in the nuclear fusion exhaust gas (Q is Hydrogen, Deuterium, Tritium). Steam Methane Reforming and Water Gas Shift reactions are used to convert $CQ_4$ and $Q_2O$ to $Q_2$ and the produced $Q_2$ is recovered by the subsequent Pd membrane. In this study, one circulation loop consisting of catalytic reactor, Pd membrane, and circulation pump was applied to recover H components from $CH_4$ and $H_2O$, one of $CQ_4$ and $Q_2O$. The conversion of $CH_4$ and $H_2O$ was measured by varying the catalytic reaction temperature and the circulating flow rate. $CH_4$ conversion was 99% or more at the catalytic reaction temperature of $650^{\circ}C$ and the circulating flow rate of 2.0 L/min. $H_2O$ conversion was 96% or more at the catalytic reaction temperature of $375^{\circ}C$ and the circulating flow rate of 1.8 L/min. In addition, the amount of $CQ_4$ generated by Korean Demonstration Fusion Power Plant (K-DEMO) in the future was predicted. Then, the treatment process for the $CQ_4$ was proposed and HAZOP (hazard and operability) analysis was conducted to identify the risk factors and operation problems of the process.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.256-261
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• 2008

Purpose: Intra-abdominal fluid collection is one of the risk factors associated with postoperative morbidity or mortality for patients who undergo gastric cancer surgery. The aim of this study was to analyze the clinicopathological characteristics of the patients with postoperative intra-abdominal fluid collection and to identify the indications for inserting a percutaneous drain (PCD) in patients with intra-abdominal fluid collection. Materials and Methods: Among the 1,277 patients who underwent operations for gastric cancer at Seoul National University Hospital between April 2005 and July 2006, the data of 117 patients with an intra-abdominal fluid collection were reviewed. Results: The number of patients' with pathologic stage I, II, III and IV disease was 42 (36.8%), 23 (20.2%), 16 (14%) and 33 (28.9%), respectively. Forty-three patients (36.3%) underwent PCD insertion and the other 43 patients received conservative management. A univariate analysis of multiple clinical variables revealed that age, gender, diabetes, liver disease, lymph node dissection, the pathologic stage and the body mass index (BMI, $kg/m^2$) were not significantly associated with PCD insertion (P>0.05). However, the univariate analysis showed that two characteristics were associated with a significantly high incidence of PCD insertion: a diameter of an intra-abdominal fluid collection greater than 4 cm and infectious signs such as leukocytosis, fever and bacteremia. Conclusion: About two thirds of the intra-abdominal fluid collections after surgery for gastric cancer were managed with only conservative method without other morbidities of mortality. Surgeons should consider performing PCD insertion if the largest diameter of an intra-abdominal fluid collection is over 4 cm or if infectious signs are seen.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.92-99
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• 2012

Many wildlife habitats have been destroyed and fragmented during the rapid industrialization and urbanization process in Korea. It is essential to connect these fragmented habitats to reduce road-kill of many types of endangered urban wildlife. The site selection for wildlife passages must take into account the behavior of the wildlife species for safe crossing utilizing many artificial barriers in urban areas. This study attempted to identify potential wildlife passage sites for the endangered and protected leopard cats of Gangseo Ecological Park in Seoul, Korea. A space syntax analysis, an analytical technique to objectively evaluate the spatial configurations related to passage selection, found that the integration value represents the accessibility and connectivity of spaces. In this paper, this means that the bigger the integration value, the more frequently the leopard cat passes through. The leopard cats were captured and radio-tracked for 72 hours once a month from March to June of 2009. The ArcGIS and Animal Movement of Hawth Tools were used to analyze the home range and movement paths, and Axwoman 4.0 was used to analyze space syntax. The daily average movement distance was $2.099{\pm}1.08km$. During the survey period, the leopard cats crossed over an urban expressway more than 20 times, running the risk of road-kill. The range of global integration values was 0.458~1.834, while that of the local integration was 0.210~6.061. Five sites that met across the leopard cats' movement routes and roads were selected to measure the local and global integrate values. Among these sites, the higher the integration value, the higher the road-kill possibility. Thus, two of five sites with high global and local integration values were suggested as potential wildlife passage sites for the leopard cats. Now, three tunnel passages are under construction at the suggested sites for which local integration value was highest (LI=4.369). Further studies are scheduled to verify these potential sites as suitable wildlife passages.