• Journal of Radiation Protection and Research
• /
• v.24 no.3
• /
• pp.131-142
• /
• 1999

By using the Korean demographic data and the modified relative risk projection model given in the Committee on the Biological Effect of Ionizing Radiation (BEIR) report-V under the U.S. National Academy of Science, the radiogenic excess risk in Korean population has been evaluated. On the basis of this risk, a safety goal for the safe operation of domestic nuclear power plants has been further derived in terms of personal dose. The baseline risk of death due to all causes in Korea and the trivial risk level, which the society considers safe, were estimated to be $5.2{\times}10^{-3}$ and $5.2{\times}10^{-6}$, respectively. The radiogenic excess cancer risk in Korea has been estimated to be $5.2{\times}10^{-3}$ for tie case of acute exposure to 0.1 Gy and $3.7{\times}10^{-3}$ for the case of chronic lifetime exposure to 1.0 mGy/y. On the basis of these risks estimate, the resulting safety goal for one year opeation of a reactor was 0.05 mSv, which is quite identical with the ALARA guideline prescribed by the USNRC in the Appendix I, 10CFR50.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.11
• /
• pp.179-185
• /
• 2020

In this paper, we propose impact factors and validity of blood variables on death of COVID-19 patients. The clinical-epidemiological data of 5628 COVID-19 patients, provided from Korea Disease Control and Prevention Agency as day of 30th April 2020, were used. As results, impact factors of death were dementia, older age, high lymphocyte, cancer, dyspnea, COPD, change of consciousness, heart disease, high platelets, abnormal diastolic pressure and fever. The validities of blood variables for death were high in the order of lymphocyte, hemoglobin, hematocrit, platelet and WBC. Therefore, risk factors such as initial clinical characteristics, underlying disease and blood test results, could be regarded for efficient management of COVID-19 patients.

• Clinical and Experimental Pediatrics
• /
• v.50 no.5
• /
• pp.443-448
• /
• 2007

Purpose : To evaluate the potential prognostic value of the antithrombin-III (AT-III) level in the children with acute lung injury (ALI), we analyzed several early predictive factors of death including AT-III level at the onset of ALI and compared the relative risk of them for mortality. Methods : Over a 18-month period, a total of 198 children were admitted to our pediatric intensive care unit and 21 mechanically ventilated patients met ALI criteria, as defined by American-European consensus conference, i.e., bilateral pulmonary infiltrates and $PaO_2/FiO_2$ lower than 300 without left atrial hypertension. Demographic variables, hemodynamic and respiratory parameters, underlying diseases, as well as Pediatric Risk of Mortality-III (PRISM-III) scores and Lung Injury Score (LIS) at admission were collected. AT-III levels were measured within 3 hours after admission. These variables were compared between survivors and non-survivors and entered into a multiple logistic regression analysis to evaluate their independent prognostic roles. Results : The overall mortality rate was 38.1% (8/21). Non-survivors showed lower age, lower lung compliance, higher PEEP, higher oxygenation index (OI), lower arterial pH, lower $PaO_2/FiO_2$, higher PRISM-III score and LIS, and lower AT-III level. PRISM-III score, LIS, OI and decreased AT-III level (less than 70%) were independently associated with a risk of death and the odds ratio of decreased AT-III level for mortality is 2.75 (95% confidence interval; 1.28-4.12) Conclusion : These results suggest that the decreased level of AT-III is an important prognostic factor in children with ALI and the replacement of AT-III may be considered as an early therapeutic trial.

• Journal of Environmental Impact Assessment
• /
• v.25 no.6
• /
• pp.514-524
• /
• 2016

The Bio-Climatic impact Assessment System, BioCAS was utilized to produce analysis maps of daily maximum perceived temperature ($PT_{max}$) and excess mortality ($r_{EM}$) over the entire Seoul area on a heat wave event. The spatial resolution was 25 m and the Aug. 5, 2012 was the selected heat event date. The analyzed results were evaluated by comparing with observed health impact data - mortality and morbidity - during heat waves in 2004-2013 and 2006-2011,respectively. They were aggregated for 25 districts in Seoul. Spatial resolution of the comparison was equalized to district to match the lower data resolution of mortality and morbidity. Spatial maximum, minimum, average, and total of $PT_{max}$ and $r_{EM}$ were generated and correlated to the health impact data of mortality and morbidity. Correlation results show that the spatial averages of $PT_{max}$ and $r_{EM}$ were not able to explain the observed health impact. Instead, spatial minimum and maximum of $PT_{max}$ were correlated with mortality (r=0.53) and morbidity (r=0.42),respectively. Spatial maximum of $PT_{max}$, determined by building density, affected increasing morbidity at daytime by heat-related diseases such as sunstroke, whereas spatial minimum, determined by vegetation, affected decreasing mortality at nighttime by reducing heat stress. On the other hand, spatial maximum of $r_{EM}$ was correlated with morbidity (r=0.52) but not with mortality. It may have been affected by the limit of district-level irregularity such as difference in base-line heat vulnerability due to the age structure of the population. Areal distribution of the heat impact by local building and vegetation, such as spatial maximum and minimum, was more important than spatial mean. Such high resolution analyses are able to produce quantitative results in health impact and can also be used for economic analyses of localized urban development.

• Korean Journal of Psychosomatic Medicine
• /
• v.26 no.2
• /
• pp.112-118
• /
• 2018

Objectives : Delirium is one of the most common mental illnesses that can affect cognitive function. Melatonin has been shown to be effective in the treatment of insomnia, and recent studies have shown a protective effect to prevent delirium. This study was conducted to investigate the efficacy of melatonin in delirium patients. Methods : All patients were referred to psychiatric department for insomnia and symptoms of delirium, and were diagnosed delirium by the DSM-5 diagnostic criteria. We compared base line severity of delirium with K-DRS-R-98-R (Korean version of Delirium Rating Scale revised 98) and after taking 2mg of melatonin, retrospectively. The side effects were also identified by referring to the medical records. Results : A total 21 patients had taken melatonin for insomnia and delirious symptoms. The K-DRS-R-98 scores were decreased from $15.24{\pm}2.64$ before treatment to $6.57{\pm}5.42$ after treatment. And CGI-S scores were also decreased from $4.14{\pm}0.48$ before treatment to $2.81{\pm}0.93$ after treatment (p<0.05). Conclusions : This study illustrates the possibility of melatonin as an effective treatment option for delirious symptoms such as disorientation, motor agitation, lability of affect and hallucinations as well as insomnia, with less concerns of drug side effect. Further study with a larger sample and prospective design will be required to confirm these results.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.8 no.2
• /
• pp.193-204
• /
• 1998

The single crystal of the $LiTaO_3$has large electro-optic effects, so it is applied to optical switch, acousto-optic deflector, and optical memory device as hologram using photorefractive effect. In this study, optic-grade undoped $LiTaO_3$and Fe:LiTaO$LiTaO_3$single crystals were grown by the Czochralski method and optical transmission and absorption spectrums were measured in the wavelength of UV-VIS range. The curie temperature was determined with DSC and by measuring capacitance for the grown undoped crystal and ceramic powder samples of various Li/Ta ratio. In case of having a 48.6 mol% $Li_2O$ as a starting Li/Ta ratio, the results of concentration variations were below 0.01 mol% $Li_2O$ all over the crystal, so it was confirmed that $LiTaO_3$single crystals were grown under congruent melting composition having optical homogeneity. The curie temperature of the Fe:$LiTaO_3$crystal was increased with increased with increased doped Fe concentrations;by the ratio of $7.5^{\circ}C$ increase per Fe 0.1 wt%. Also, the optical transmittance was about 78 %, which was sufficient for optical device.

• Childhood Kidney Diseases
• /
• v.11 no.2
• /
• pp.247-254
• /
• 2007

Purpose : Continuous renal replacement therapy(CRRT) has been the first choice for the treatment of acute renal failure in critically ill children not only in western countries but also in Korea. However, there are very few studies that have analyzed the outcome and prognosis of this modality in Korean children. We performed this study to evaluate the factors associated with the outcome and prognosis of patients treated with CRRT. Methods : We retrospectively reviewed the medical records of 32 children who had received CRRT at Severance hospital from 2003 to 2006. The mean age was 7.5 years(range 4 days-16 years) and the mean body weight was 25.8 kg (range 3.2-63 kg). Results : Eleven(34.4%) of the 32 patients survived. Bone marrow transplantation and malignancy were the most common causes of death and underlying disease leading to the need for CRRT Mean patient weight, age, duration of CRRT, number of organ failures, urine output, estimated glomerular filtration rate(eGFR), C-reactive protein, and blood urea level did not differ significantly between survivors and nonsurvivors. (1) Pediatric risk of mortality(PRISM) III score at CRRT initiation($9.8{\pm}5.3$ vs. $26.7{\pm}7.6$, P<0.0001), (2) maximum pressor number ($2.1{\pm}1.2$ vs. $3.0{\pm}1.0$, P=0.038), and (3) the degree of fluid overload($5.2{\pm}6.0$ vs. $15.0{\pm}8.9$, P=0.002) were significantly lower in survivers than in nonsurvivors. Multivariate analysis revealed that fluid overload was the only independent factor reducing survival rate. Conclusion : CRRT was successfully applied to the treatment of acute renal failure in a wide range of critically ill children. To improve survival, we suggest the early initiation of CRRT to prevent the systemic worsening and progression of fluid overload in critically ill children with acute renal failure. (J Korean Soc Pediatr Nephrol 2007;11:247-254)