• The Korean Journal of Applied Statistics
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• v.19 no.1
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• pp.183-193
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• 2006

We consider a new classification method(DnDclass) combining two classification rules based on $L_1$-distance(L1DISTclass) and $L_1$-data depth(L1DDclass). To investigate characteristics and to evaluate the performance of these classification methods, we use simulation data in various settings. Through this simulation study, we can confirm that the new method, DnDclass, performs relatively well in many cases.

• Environmental Engineering Research
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• v.25 no.3
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• pp.439-445
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• 2020

In the estimation of the aerosol single fiber efficiency using fibrous filters, there is a size range, where the particles penetrate most effectively through the fibrous collectors, and corresponding minimum single fiber efficiency. For small particles in which the diffusion mechanism is dominant, the Cunningham slip correction factor (C_c) affects the single fiber efficiency and the most penetrating particle size (MPPS). Therefore, for accurate estimation, C_c is essential to be considered. However, many previous studies have neglected this factor because of its complexity and the associated difficulty in deriving the appropriate parameterization particularly for the MPPS. In this study, the expression for the MPPS, and the corresponding expression for the minimum single fiber efficiency are analytically derived, and the effects of C_c are determined. In order to accommodate the slip factor for all particle-size ranges, C_c is simplified and modified. Overall, the obtained analytical expression for the MPPS is in a good agreement with the exact solution.

• Nutrition Research and Practice
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• v.14 no.1
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• pp.3-11
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• 2020

BACKGROUND/OBJECTIVES: Oxidative stress causes cell damage and death, which contribute to the pathogenesis of neurodegenerative diseases. Urolithin A (UA), a gut microbial-derived metabolite of ellagitannins and ellagic acid, has high bioavailability and various health benefits such as antioxidant and anti-inflammatory effects. However, it is unknown whether it has protective effects against oxidative stress-induced cell death. We investigated whether UA ameliorates H₂O₂-induced neuronal cell death. MATERIALS/METHODS: We induced oxidative damage with 300 μM H₂O₂ after UA pretreatment at concentrations of 1.25, 2.5, and 5 μM in SK-N-MC cells. Cytotoxicity and cell viability were determined using the CCK-8 assay. The formation of reactive oxygen species (ROS) was measured using a 2,7-dichlorofluorescein diacetate assay. Hoechst 33342 staining was used to characterize morphological changes in apoptotic cells. The expressions of apoptosis proteins were measured using Western blotting. RESULTS: UA significantly increased cell viability and decreased intracellular ROS production in a dose-dependent manner in SK-N-MC cells. It also decreased the Bax/Bcl-2 ratio and the expressions of cytochrome c, cleaved caspase-9, cleaved caspase-3, and cleaved PARP. In addition, it suppressed the phosphorylation of the p38 mitogen-activated protein kinase (MAPK) pathway. CONCLUSIONS: UA attenuates oxidative stress-induced apoptosis via inhibiting the mitochondrial-related apoptosis pathway and modulating the p38 MAPK pathway, suggesting that it may be an effective neuroprotective agent.

• Journal of agricultural medicine and community health
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• v.28 no.1
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• pp.15-27
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• 2003

Objectives: This study was conducted to compare the medical care patterns of hypertensive patients between rural and urban areas. Methods: We selected one rural county(Region A where there were 19 public health centers; one health center, 8 health sub-centers and 10 community health posts) and two urban districts(Region B and C where there was no health sub-center and community health post) in Daegu city. Region B had similar socioeconomic characteristics with rural county A while region C had different characteristics. The medical insurance records of 14,422 incident patients (2,501 in region A, 4,873 in region B and 7,048 in region C) with diagnostic code of hypertension from September 1998 to August 1999 were reviewed. Incident patient was defined as a patient who had no record of medical fee claim for hypertension to the national health insurance corporation in past 6 months and visited a medical facility for hypertension for the first time. The data for annual visit days, annual prescription days and annual total medical expenses were abstracted. The medical care pattern was categorized by the number of annual visit days and prescription days. The most proper care group was defined as the patient who visited 6-15 days with 240 prescription days or more in a year. Results: The type of medical facilities for the most visit was clinics, 373.% and it was followed by general hospitals, 28.2%; public health centers, 24.7%; and hospitals, 9.8% in region A(p<0.05). In region B, it was clinics, 63.1% and followed by general hospitals, 27.6%; health center, 5.2%; and hospitals, 4.1%(p<0.05). In region C, it was clinics, 53.8% and followed by general hospitals, 35.0%; health center, 6.3%; and hospitals, 4.9%(p<0.05). Annual mean total medical expenses per patient was highest in region C(won195,993) and followed by region A(won191,683) and region B(won178,713). The proportion of the most proper care group was 7.7% in region A, 5.2% in region B and 6.7% in region C(p<0.05). According to the type of medical facilities for the first visit, the proportion of the most proper care group was highest(14.7%) in the patients of public health centers, and it was followed by general hospitals, 8.8%; clinics, 3.6%; and hospitals, 2.0% in region A(p<0.05). In region B, it was highest in general hospitals, 9.7% and followed by hospitals, 4.0%; health center, 3.6%; and clinics, 3.4%(p<0.05). In region C, it was highest in general hospitals, 10.1% and followed by clinics, 5.2%; hospitals, 4.1%; and health center, 3.1%(p<0.05). Conclusions: The proportion of proper care for hypertension was higher in rural area and it was attributed to the care of health center, sub-centers and community health posts which appeared to follow patients better than hospitals and clinics.

• Journal of Veterinary Science
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• v.23 no.2
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• pp.21.1-21.7
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• 2022

Newcastle disease (ND), infectious laryngotracheitis (ILT) and avian metapneumovirus (aMPV) can be similar making it critical to quickly differentiate them. Herein, we adapted pre-existing molecular-based diagnostic assays for NDV and ILTV, and developed new assays for aMPV A and B, for use under synchronized thermocycling conditions. All assays performed equivalently with linearity over a 5 log₁₀ dynamic range, a reproducible (R² > 0.99) limit of detection of ≥ 10 target copies, and amplification efficiencies between 86.8%-98.2%. Using biological specimens for NDV and ILTV showed 100% specificity. Identical amplification conditions will simplify procedures for detection in diagnostic laboratories.

• Toxicological Research
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• v.30 no.3
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• pp.199-204
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• 2014

The aim of this research was to improve our understanding of human toxicity due to exposure to DMF, MEK, or TOL individually as compared to exposure to DMF-MEK or DMF-TOL mixtures, by comparing $EC_{50}$ values as well as the morphological changes in HepG2 cells treated with these substances. We found that there was marked cell necrosis in the groups treated with mixtures than in those treated with the compounds alone, and that the amount of cell death and the $EC_{50}$ value were more dependent on MEK and TOL than on DMF. Moreover, analysis of the changes in effective concentration curves revealed that MEK had an antagonistic effect on the human toxicity of DMF, whereas TOL had a synergistic effect. Accordingly, these results suggest that in workplaces involved in the manufacture of synthetic leather, mixtures of DMF and TOL should be avoided as much as possible in order to minimize environmental toxicity and protect the health of the workers.

• Journal of Preventive Medicine and Public Health
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• v.23 no.3 s.31
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• pp.316-323
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• 1990

To analyze of determinants influencing the utilization of the rural health sub-centers (HSCs), 116 of 144 HSCs in Kyong Gi Do, were selected for this study. The self-administered questionnaire covering the environment and the characteristics of doctors working in the HSCs was sent to HSCs by mail. 105 questionnaires were returned of which 88 were completed and use in the study. The dependant variable was the total number of medical care visits to the HSCs from January 1, 1990 to March 31, 1990. Data was analyzed by multiple regression analysis. The results were as follows : First, the more time required to set from the HSCs to nearest hospital or clinic, the higher the utilization of the HSCs. Second, the more geographically accessible the HSCs was, the more utilization the HSCs. Third, the older of the HSCs doctors were, the more utilization of the HSCs. Fourth, the higher frequency of bus service from the HSCs to town, the more utilization of the HSCs. Fifth, the more time required from the HSCs to town, the more utilization of the HSCs. Therefore, the determinants influencing the utilization of the rural HSCs in Kyong-Gi Do, are mostly geographical accessibility of medical care.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2004.11a
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• pp.167-170
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• 2004

• Safety and Health at Work
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• v.13 no.3
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• pp.326-335
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• 2022

Background: One of the important actions for enhancing human reliability in any industry is assessing human error probability (HEP). The HEART technique is a robust tool for calculating HEP in various industries. The traditional HEART has some weaknesses due to expert judgment. For these reasons, a hybrid model is presented in this study to integrate HEART with Best-Worst Method. Materials Method: In this study, the blasting process in an iron ore mine was investigated as a case study. The proposed HEART-BWM was used to increase the sensitivity of APOA calculation. Then the HEP was calculated using conventional HEART formula. A consistency ratio was calculated using BWM. Finally, for verification of the HEART-BWM, HEP calculation was done by traditional HEART and HEART-BWM. Results: In the view of determined HEPs, the results showed that the mean of HEP in the blasting of the iron ore process was 2.57E-01. Checking the full blast of all the holes after the blasting sub-task was the most dangerous task due to the highest HEP value, and it was found 9.646E-01. On the other side, obtaining a permit to receive and transport materials was the most reliable task, and the HEP was 8.54E-04. Conclusion: The results showed a good consistency for the proposed technique. Comparing the two techniques confirmed that the BWM makes the traditional HEART faster and more reliable by performing the basic comparisons.

• Journal of Society of Preventive Korean Medicine
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• v.6 no.1
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• pp.1-14
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• 2002

The proportion and role of public sector in health care industry is very small in Korea. Asymmetric distribution of health care resources is one of the major health care concerns. This issue is so important that it raises a question of accessibility, availability, continuity of care and equity of rural area people's health care utilization. To solve these problems and to satisfy the basic demand of oriental medical service in rural areas, the oriental public health doctors were placed in rural health centers since 1998. The main objectives of this study are twofold: to measure the cognition and attitude of health center directors on the strategies for utilizing oriental public health doctors and to provide basic data for improving the health manpower management program. Data have been collected by way of the self-administrative questionnaires. Developing the questionnaire, the literature review on the previous studies and delphi method were carried out. The response rate was 38.7%. The results of this study are summarized as follows; 1. community people respond positively on the oriental medical service activity in health center. 2. In regard to workloads of oriental public health doctor, 'appropriate' was 81.1% and 'burdensome' was 18.2%, respectively. 3. The 94.0% of respondents thought that the oriental medical service will be continued. 4. To activate oriental medical service in health center, the sufficient budget and provision of aid workers is a necessity. 5. The 75.5% of health center directors respond positively on the allocation of oriental public health doctor to health sub-centers. 6. Health center directors agreed that oriental public health doctor should perform the clinical service as well as prevention and health promotion activity. These results recommend that oriental medical service in health center should be continued gradually, and oriental public health doctors working at health center perform their work efficiently. Undoubtedly, their activity should be more focused on health promotion and disease prevention than daily patient care. For achieving this objective, more support of governmental policy is essential for utilizing oriental public health doctor and better health of the rural area community people.