• Toxicological Research
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• v.17
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• pp.41-45
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• 2001

The methods used for risk assessment from exposure to chemicals are well established. in most cases where toxicity other than carcinogenesis is being considered, the standard method relies on establishing the No Observed Adverse Effect Level (NOAEL) in the most sensitive animal toxicity study and using an appropriate safety factor (SF) to determine the exposure which would be associated with an acceptable risk. For carcinogens a different approach is used because it has been argued there is no threshold of effect. Thus mathematical equations are used to extrapolate from the high doses used in ani-mal experiments. These methods have been strongly criticised in recent years on several grounds. The most cogent criticisms are a) the equations are not based on a thorough understanding of the mechanisms of carcinogenesis and b) the outcome of a risk assessment based on such models varies more as a consequence of changes to the assumptions and equation used than it does from the data derived from carcinogenicity experiments. Other criticisms include the absence of any measure of the variance on the risk assessment and the selection of default values that are very conservative. Recent advances in the application of risk assessment emphasise that measures of both the exposure and the hazard should be considered as a distribution of values. The outcome of such a risk assessment provides an estimate of the distribution of the risks.

• Environmental Engineering Research
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• v.20 no.3
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• pp.212-222
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• 2015

Experiments were conducted on the immobilization of eight heavy metals (HMs) (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) during 20-day rotary drum composting of water hyacinth. The Tessier sequential extraction procedure was used to investigate the fractionation of HMs. The eco-toxicity risk of HMs was assessed by risk assessment code (RAC). In the results, the bioavailability factor (BAF) for different HMs presented in the following order: Mn > Zn = Fe > Cu > Cr > Cd = Pb > Ni. The total concentration of Pb was higher than that of Zn, Cu, Mn, Cd and Cr; however, its BAF was the lowest among these HMs. These results confirmed that the eco-toxicity of HMs depends on bioavailable fractions rather than on the total concentration. The greatest reduction in bioavailability and eco-toxicity risk of HMs occurred in lime 1% and 2% as compared to control and lime 3%. The eco-toxicity risk of Fe, Ni, Pb, Cd and Cr was reduced from low risk to zero risk by rotary drum composting. These studies demonstrated the high efficiency of the rotary drum for degrading compost materials and for reducing the bioavailability and eco-toxicity risk of HMs during the composting process.

• Research in Community and Public Health Nursing
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• v.16 no.4
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• pp.392-403
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• 2005

Purpose: This study was to evaluate the nutritional status of low-income elders in urban areas and factors affecting their nutritional risk. Methods: A cross-sectional analysis was conducted. The subjects were 300 elders selected from home visiting clients of DongJack Public Health Center. Data were collected using a questionnaire containing questions on socio-demographic characteristics. health behavior and disease. dietary pattern. Nutritional Screening Initiative. Geriatric Depression Scale and Barthel Index for ADL. Collected data were analyzed through descriptive statistics. $X^2-test$ and multiple regression analysis using SPSS. Results: Of the subjects, 63% had high nutritional risk, 21.3% moderate nutritional risk, and 15.7% good nutritional risk. NSI score was significantly different according to economic status, subjective health condition, medication, dental health, depression. regularity of diet and meal with family. Multiple regression analysis revealed that depression, subjective health condition, dental health and regularity of diet and meal with family explain 38.1% of nutritional risk. Conclusion: It is necessary to evaluate nutrition status and to control nutritional risk factors such as depression, dental health, regularity of diet and meal with family for improving the health of the low-income elderly.

• Sleep Medicine and Psychophysiology
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• v.20 no.1
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• pp.22-30
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• 2013

Objectives: Sleep problems has been consistently reported as a suicidal risk factor in adults and, recently, also in adolescents. In this study, dividing study subjects by the previous suicidal behaviors (suicidal vs non-suicidal), we compared the group differences of suicidal risk factors, and examined the possibility of sleep as a suicidal risk factor. Methods: Study subjects were 561 (271 boys and 290 girls) from a community sample of high school students. Suicidal Risk Behavior Checklist, Center for Epidemiological Study-Depression (CES-D), Symptom Checklist-90-Revision (SCL-90-R) Anxiety and Aggression subscale, Pittsburg Sleep Quality Index (PSQI) were done. Results: Forty six students (8.1%) reported previous actual self-harm behavior as a suicidal attempt, 181 students (32.4%) reported having suicidal thought only. Three hundred thirty four students (59.5%) reported no previous suicidal behavior (thought and attempt, both). Suicidal behavior group showed higher score on risk behaviors such as school violence, substance use and internet addiction. CES-D, SCL-90-R, PSQI showed significant group difference. Logistic regression analysis showed suicidal risk were significantly associated with depression, stress in suicidal risk factors and sleep latency, daytime dysfunction in PSQI. Analysis of variance (ANOVA) shows the most prolonged sleep latency and increased index of all PSQI components except sleep efficiency in suicidal attempt group. Conclusions: Sleep Problems had a strong association with the suicidal risk behavior in adolescents. Sleep problems, especially, prolonged sleep latency, daytime dysfunction might be important markers for suicidal behavior. Screening for sleep problems in adolescents are encouraged for the parents, school teachers, and related medical physicians.

• Journal of Preventive Medicine and Public Health
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• v.56 no.5
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• pp.475-480
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• 2023

Objectives: This study examined differences in health care spending and characteristics among older adults in Korea by high-cost status (persistently, transiently, and never high-cost). Methods: We identified 1 364 119 older adults using data from the Korean National Insurance Claims Database for 2017-2019. Outcomes included average annual total health care spending and high-cost status for 2017-2019. Linear regression was used to estimate differences in the outcomes while adjusting for individual-level characteristics. Results: Persistently and transiently high-cost older adults had higher health care spending than never high-cost older adults, but the difference in health care spending was greater among persistently high-cost older adults than among transiently high-cost older adults (US$20 437 vs. 5486). Despite demographic and socioeconomic differences between transiently high-cost and never high-cost older adults, the presence of comorbid conditions remained the most significant factor. However, there were no or small differences in the prevalence of comorbid conditions between persistently high-cost and transiently high-cost older adults. Rather, notable differences were observed in socioeconomic status, including disability and receipt of Medical Aid. Conclusions: Medical risk factors contribute to high health care spending to some extent, but social risk factors may be a source of persistent high-cost status among older adults in Korea.

• Neonatal Medicine
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• v.25 no.3
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• pp.91-95
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• 2018

Bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) is increasingly being recognized as a cause of morbidity and mortality in preterm infants. Recently, BPD-PH has also been shown to have additional long-term negative effects on neurodevelopmental outcomes and right ventricular function. Several significant risk factors associated with the development of BPD-PH have been identified. A screening strategy for BPD-PH is needed for infants presenting more than one risk factor. In addition, an early echocardiogram within 14 days of age may be a useful tool to identify infants at high-risk for BPD-PH. We have reviewed recent progress in research concerning clinical characteristics, presentation, and outcomes of BPD-PH and have suggested direction for future studies.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.267-273
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• 2011

Since 'The Act on Private Investment of The Infrastructure' was established in 1994, private investment as well as government's investment in transport infrastructure has been active. However investment in transport infrastructure has more risks than others' due to uncertainty both in traffic volume and in construction cost. In the current appraisal procedure of deciding transportation infrastructure investment, instead of risk management, the sensitivity analysis considering only the changes of benefit, cost and social discount rate which are main factor affecting economic feasibility is carried out. Therefore the uncertainty of various factors affecting demand, cost and benefit are not considered in feasibility study. In this study the problems in current investment appraisal system were reviewed. Using Delphi technique the major factors which have high uncertainty in feasibility study were surveyed and then improvement plan was suggested in the respective of classic 4 step demand forecasting method. The range estimation technique was also mentioned to deal with the uncertainty of the future.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1257-1264
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• 2011

Delirium is a neuropsychiatric disorder accompanying symptoms of hallucination, drowsiness, and tremors. It has high occurrence rates among elders, heart disease patients, and burn patients. It is a medical emergency associated with increased morbidity and mortality rates. That s why early detection and prevention of delirium ar significantly important. And This mental illness like delirium occurred by complex interaction between risk factors. In this paper, we identify risk factors and interactions between these factors for delirium using multi-factor dimensionality reduction (MDR) method.

• Journal of Preventive Medicine and Public Health
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• v.39 no.6
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• pp.447-454
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• 2006

Objectives : To determine obesity for the screening of individuals at high risk of coronary heart disease in urban areas. Methods : Data were obtained from 4,137 adults between 19 and 85 years of age (2,372 males, 1,765 females), not recognized as taking medicines for cardiovascular diseases, who underwent a health check-up at the health promotion center of university hospitals in cities between Jan. 2003 and Dec. 2004. The variables studied were divided into two broad categories, and their relationships examined. obesity indices and risk factors for coronary heart disease. To reveal the relation between each of the obesity indices and the proportion of individuals at risk of coronary heart disease, the obesity indices were stratified and odds ratios obtained after age adjustment. Results : From a gender comparison of anthropometric measures, men were found to have significantly greater heights, weights, and waist and hip circumferences than women. From a gender comparison by the obesity indices, women were found to have significantly higher BMI, %Fat, waist to hip and waist to stature ratios than men. As obesity indices, the waist to stature ratio and the waist circumference were strongly correlated with coronary risk factors, both in men and women. The age-adjusted odds ratio of coronary risk factors increased significantly with increasing waist circumference, BMI, %fat, waist to hip and waist to stature ratios, and were highest specifically for the waist to stature ratio and the waist circumference. Conclusions : The study results showed that the waist to stature ratio and the waist circumference, as obesity indices, were most closely correlated with coronary risk factors. It is suggested that the waist to stature ratio and, specifically, the waist circumference can be effectively used in the field of health management for screening those with high levels of coronary risk factors.

• Journal of Chest Surgery
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• v.47 no.3
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• pp.262-268
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• 2014

Background: The development of diagnostic techniques and an awareness of health examinations can bring about an early diagnosis of lung cancer. However, appropriate postoperative management and adjuvant chemotherapy remain under debate in postoperative therapeutic strategy. The present study was conducted to assess the clinicopathologic factors that influence recurrence and prognosis after complete resection of lung cancer. Methods: The present study analyzed 62 patients with lung cancer who underwent complete resection of diagnosed adenocarcinoma between 1994 and 2007. In addition to conventional factors, which include staging factor and histological evaluation, the present study also performed univariate and multivariate analyses to consider claudin, a cell adhesion molecule, as a prognostic factor by immunohistochemical staining. Results: There was no correlation between conventional factors, including lymphatic and vascular invasion, and recurrence. However, there was a significant correlation between high expression of claudin 4 and cancer recurrence. In particular, there was a correlation between high expressions of claudin 1, 4, and 5 and a reduction of disease-free survival. Conclusion: Increased expressions of claudin 4 were negative prognostic factors in adenocarcinoma of the lung and thus could be used to identify high-risk patients for adjuvant chemotherapy, even if they had early-stage lung cancer. The present findings collectively suggest that consideration of claudin as a prognostic factor in the active postoperative treatment in patients at high risk will lead to better therapeutic outcomes with fewer side effects.