• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.127-134
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• 2008

Potential economic impact of a hypothetical severe accident at a nuclear power plant(Uljin units 3/4) was estimated by applying the Delphi method, which is based on the expert judgements and opinions, in the process of quantifying uncertain factors. For the purpose of this study, it is assumed that the radioactive plume directs the inland direction. Since the economic risk can be divided into direct costs and indirect effects and more uncertainties are involved in the latter, the direct costs were estimated first and the indirect effects were then estimated by applying a weighting factor to the direct cost. The Delphi method however subjects to risk of distortion or discrimination of variables because of the human behavior pattern. A mathematical approach based on the Bayesian inferences was employed for data processing to improve the Delphi results. For this task, a model for data processing was developed. One-dimensional Monte Carlo Analysis was applied to get a distribution of values of the weighting factor. The mean and median values of the weighting factor for the indirect effects appeared to be 2.59 and 2.08, respectively. These values are higher than the value suggested by OECD/NEA, 1.25. Some factors such as small territory and public attitude sensitive to radiation could affect the judgement of panel. Then the parameters of the model for estimating the direct costs were classified as U- and V-types, and two-dimensional Monte Carlo analysis was applied to quantify the overall economic risk. The resulting median of the overall economic risk was about 3.9% of the gross domestic products(GDP) of Korea in 2006. When the cost of electricity loss, the highest direct cost, was not taken into account, the overall economic risk was reduced to 2.2% of GDP. This assessment can be used as a reference for justifying the radiological emergency planning and preparedness.

• Journal of Chest Surgery
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• v.36 no.6
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• pp.384-390
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• 2003

Background: Since Ross and Sormeville first reported the use of aortic homograft valve for correction of pulmonary atresia in 1966, homograft valves are widely used in the repair of congenital anomalies as conduits between the pulmonary ventricle and pulmonary arteries. On the basis of these results, we have used it actively. In this report, we describe our experience with the use of cryopreserved valved homograft conduits for infants and children requiring right ventricle to pulmonary artery connection in various congenital cardiac anomalies. Material and Method: Between January, 1996 and December 2001, 27 infants or children with a median age of 16 months(range 9days to 18years) underwent repair of RVOTO using homograft valved conduit by two surgeons. We studied 22 patients who have been followed up at least more than one year. The diagnosis at operation included pulmonary atresia with ventricular septal defect (n=13), truncus arteriosus (n=3), TGA or corrected TGA with RVOTO (n=6). Homograft valved conduits varied in size from 15 to 26 mm (mean, 183.82 mm). The follow-up period ranged from 12 to 80.4 months (median, 48.4 months). Result: There was no re-operation due to graft failure itself. However, early progressive pulmonary homograft valve insufficiency developed in one patient, that was caused by dilatation secondary to the presence of residual distal pulmonary artery stenosis and hypoplasia after repair of pulmonary atresia with ventricular septal defect. This patient was required reoperation (conduit replacement). During follow-up period, there were significant pulmonary stenosis in one, and pulmonary regurgitation more than moderate degree in 3. And there were mild calcifications at distal anastomotic site in 2 patients. All the calcified homografts were aortic in origin. Conclusion: We observed that cryopreserved homograft conduits used in infant and children functioned satisfactorily in the pulmonic position at mid-term follow-up. To enhance the homograft function, ongoing investigation is required to re-establish the optimal strategy for the harvest, preservation and the use of it.

• Journal of Chest Surgery
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• v.38 no.12 s.257
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• pp.807-814
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• 2005

Background: Cardiopulmonary bypass is an essential process to maintain circulation for saving life during the cardiac surgery, But it is a process in which systemic inflammation was evoked inevitably because of the exposure of blood to foreign surface. The injuries to distal organs during the cardiopulmonary bypass were resulted from systemic inflammation and the disturbances of micro-circulations in the organs. We designed this study to research the effects of leukocyte depletion from pump-oxygenator priming solution on the systemic inflammation, and the micro-circulation of gastric mucosa that is suggested by the gastric mucosal $CO_{2}$ partial pressure and acidity. Material and Method: The dogs were divided into three groups according to the different pump-oxygenator priming solutions; non-hemic crystalloid solution; leukocyte-depleted homologous blood; and non leukocyte-depleted homo-logous blood. Each priming solution group contained five dogs. In all three groups, 2 hours of cardiopulmonary bypass, and 4 consecutive hours of general anesthesia was maintained on the mechanical ventilation. Each dog was evaluated for the gastric mucosal pH, $CO_{2}$ partial Pressure, arterial pH, $CO_{2}$ partial pressure, the exhaled air $CO_{2}$ partial pressure and the level of IL-8 on before the cardiopulmonary bypass, 1 hour after the cardiopulmonary bypass, 2 hours after the cardiopulmonary bypass, 2 hours after the restoration of normal circulation, and 4 hours after the restoration of normal circulation after the cardiopulmonary bypass. The levels of IL-8 were measured with ELISA (enzyme linked immunosorbent assay) technique. Result: 1. There were significant differences of gastric mucosal $CO_{2}$ partial pressure between the leukocyte-depleted homologous blood group and other two groups(vs non leukocyte-depleted homologous blood group; P=0.02, vs non-hemic crystalloid solution group; P=0,01). 2. The gastric mucosal pH of leukocyte-depleted homologous blood group was significantly different from non leukocyte-depleted homologous blood group (p=0.01). 3. The levels of IL-8, which examine the systemic inflammation, showed signi- ficantly better results in leukocyte-depleted homologous blood group and non-hemic crystalloid solution group than non leukocyte-depleted homologous blood group (p=0.01, 0.01). Conclusion: Based upon these results, we concluded that the leukocyte depletion from the pump-oxygenator priming solution has a beneficial effects in reducing systemic inflammation and the preserving of gastric mucosal micro-circulation.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.23-28
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• 1977

Acetylene-ethylene($C_2H_2-C_2H_4$) assay was carried out to find the heterotrophic nitrogen-fixing activities and distribution of nitrogen fixers in eleven different soil series which are located in Kyeonggi province. Following are the summaries of this study. 1. Acetylene-reducing activities were higher in Gwanghwal, Mangyeong and Buyong series which are derived from fluviomarine deposite than in Yeongsan, Hamchang and Pyeongtack series which are observed from continental alluvial plain. The lowest activities are observed in Yecheon, Hoegog, and Jisan series which are situated in local valley region. 2. Estimated amouts of $N_2$ per annum fixed by $N_2$-fixing heterotrophs were about 3.2kg in fuluvio marine soils, 2.6kg in continental alluvial plain and 2.0kg/10a in local valley region, respectively. 3. Azotobacter and Beijerinckia were not detected in any of the ten different soil series except in Pyeongtaeg series. However, Clostridia, anaerobic nitrogen fixer, was detected in order of ${\times}10^2$. It is assumed that these population are not enough to contribute to the nitrogen supply by the biological fixation in paddy soil. 4. For the assesment of heterotrophic nitrogen fixation in paddy soil, it must be presumed that aerobes, anaerobes and phototrophs which can grow on nitrogen free media may greatly contribute for the asymbiotic netrogen fixation.

• Korean Journal of Medicinal Crop Science
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• v.2 no.3
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• pp.181-186
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• 1994

Vegetative node and rhizome of Ligusticum chuanxiong Hort. were planted in spring and autumn and harvested after one and two years to determine the appropriate harvesting time which produced a high yield. Plant height, leaf number and branch number per plant were increased in order of rhizome planted in spring and harvested after two year(RST), rhizome planted in autumn and harvested after one year(RAO), vegetative node planted in autumn and harvested after one year(VNAO), and vegetative node planted in spring and harvested after one year(VNSO). Leaf area index and dry leaf weight in VNSO were highest on August 16, but dry weights of stem and rhizome was increased until harvesting time. The appropriate harvesting time was October 17, in RST, November 9 in RAO and VNAO, and November 13 in VNSO. Yield in autumn planting was more increased than that in spring planting and also that in RST was 443kg per 10a and increased by 2.8 times compared to RAO. However the yield in the rhizome planting was more increased by 17 percent than the vegetative node planting, the latter planting was inexpensive and economic for purchasing seed materials.

• Korean Journal of Medicinal Crop Science
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• v.2 no.3
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• pp.198-204
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• 1994

This study was carried out to investigate the auxin(IAA, IBA, NAA) treatment and the effect of shading rate in Asarum sieboldii. The results obtained were summerized as follows: By the soaking treatment of auxins to the cutted rhizome enhanced root growth and plant weight. By the increment of shading rate, plant growth was much better compare to the control. Leaf fallen times appeared about 20 days more earlier at plain area then the alpain area. Root yield was much higher by the treatment of shading then the conventional cultivation so it seem to be the useful for large scale cultivations of A. sieboldii.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1030-1039
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• 1997

Background : Impulse Oscillometry is a noninvasive and effort-independent test used to characterize the mechanical impedance of the respiratory system. The clinical potential of the IOS is rapid and demands only passive cooperation which makes it especially appealing for children, for epidemiologic surveys and for conditions in which quiet breathig instead of forced expiratory maneuvers are preferred. However, several studies have shown conflicting results that the role of IOS about detection of smoking induced small airway diseases or early airway obstruction Methods : Study was to evaluate the clinical ability of the IOS to detect about smoking induced early airway obstruction in persons with normal spirometry test. Respiratory asymptomatic study groups were formed that one is non-smoking group, another is smoking group. Results : The parameters of spirometry were not significantly differences between non-smoking group and smoking group. Among the parameters of IOS, total resistance(non-smoking group : smoking group=$2.22{\pm}1.20$ : $2.58{\pm}1.71$), peripheral resistance($1.25{\pm}0.62$ : $1.47{\pm}0.10$), bronchial compliance($0.44{\pm}0.12$ : $0.47{\pm}0.16$) were not statistically significant different (p<0.05), but central resistance and lung compliance were not statistically significant different (unit ; resistance=hPa/l/s, compliance=l/hPa). Resistance(Rrs) was not statistically significant different with changes of frequences(5, 10, 15, 20, 25, 30, 35Hz), but Reactance(Xrs) was statistically significant different with low frequences that X5(non-smoking group : smoking group=$-0.62{\pm}0.28$ : $-0.76{\pm}0.48$, p<0.001) and X10($-0.06{\pm}0.19$ : $-0.15{\pm}0.33$, p<0.013) (unit; hPall/s, $hPa{\cong}cmH_2O$). Conclusion : Impulse oocillometer(IOS) is clinically available method to detect about smoking induced early airway obstruction. And clinically potential parameters of IOS were considers that total resistance, peripheral resistance, bronchial resistance, and reactance of low frequency at 5Hz, 10Hz.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.907-913
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• 1997

Background : Congenital bronchoesophageal fistula(BEF) presented in adult life is a rare disorder and has characteristic clinical findings such as paroxysmal cough after water ingestion and recurrent respiratory infections. It usually manifested recurrent pneumonia and chronic cough with purulent phlegmon which was mis-or under-diagnosed as chronic bronchitis, bronchiectasis or lung abscess so forth. Methods : We reviewed retrospectively 13 cases of congenital BEF in adult of Paik Hospital, College of Medicine, Inje University including 22 cases of congenital BEF previously reported in literature of Korea from 1979 through 1995. Results : The mean age at diagnosis was $40.2{\pm}14.3$. There was no difference in sex ratio(Male : Female 18 : 17). The most common symptom was cough(91.4%), followed by chronic sputum(74.3), hemoptysis(25.7), and paroxysmal nocturnal cough at specific position(20%). Twenty one of 31 patients who were able to review have the most specific sign, Ono's sign presented as paroxysmal cough after liquid ingestion. By classification of Braimbridge-Keith, Fourteen(45.1%) of 31 patients were group I (associated with esophageal diverticulum), 15(48.4%) were group II (simple fistula), and group Ill and IV was one case in each. The opening of fistula confined to right lower lobe in 26(76.5%), left lower lobe in 6(17.6%), and left main bronchus in 2(5.9%) cases. Conclusion : Congenital bronchoesophageal fistula is uncommon disorder which has characteristic histories and specific symptoms such as chronic and recurrent lower respiratory infections, and paroxysmal cough after liquid ingestion. Medical attention and careful history should be done in patients who have localized recurrent lower respiratory infections in right lower lobe.

• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.295-298
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• 2005

We report a case of a 48-year-old man with a paradoxic upper airway obstruction and central sleep apnea that developed after an anterior cervical spinal fusion. Nine months before being admitted to this hospital, he was diagnosed with a herniated intervertebral disc between the 5th and 6th cervical spine, and the first operation was carried out. Two months later, a pseudoarthrosis has developed and a second operation, an anterior interbody fusion of the C5 and C6 using autogenous strut bone graft, was performed. After the second operation, he began to complain of snoring, excessive daytime sleepiness, insomnia, and a bizarre sound heard near the upper airway during breathing. Nasopharyngoscope and magnetic resonance imaging disclosed a paradoxical narrowing of the nasopharynx during expiration. On the overnight polysomnography, the apnea index was 8.7/h (central apnea, 7.0/h; obstructive apnea, 1.7/h). Nasal continuous positive airway pressure was applied, but he complained of pressure-intolerance, and laser-assisted uvulopalatoplasty was then performed. Two months after surgery, clinical symptoms as well as the apneas had improved markedly. We suggest that this paradoxic upper airway obstruction might be associated with the anterior cervical spinal surgery even though the mechanism is unclear. This case also emphasizes that an upper airway obstruction can contribute to the development of central sleep apnea.

• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.523-531
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• 2004

Background : Bronchoscopy in patients on mechanical ventilation is being performed much more frequently. However, there is little data on the changes in physiologic parameters and no established mechanical ventilation protocol during bronchoscopy. A decreasing or the removal of positive end-expiratory pressure (PEEP) during bronchoscopy may precipitate severe hypoxemia and/or derecruitment. Methods : Our standardized mechanical ventilation protocol, without changing the PEEP level, was used during bronchoscopy. The physiological parameters were measured during the bronchoscopic procedure. Results : During bronchoscopy, respiratory acidosis, elevation of peak pressure, elevation of heart rate and auto-PEEP were developed, but were reversible changes. Procedure-related gross barotraumas or other severe complications did not developed. Conclusion : No serious complications developed during bronchoscopy under our standardized mechanical ventilation protocol when the PEEP level remained unchanged. The procedure time should be kept to a minimum to decrease the exposure time to undesirable physiological changes.