• Journal of radiological science and technology
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• v.47 no.4
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• pp.271-278
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• 2024

This study aimed to evaluate the impact of changes in beam arrangement and arc counts on dosimetric factors in volumetric modulated arc therapy (VMAT) inverse radiation therapy planning for hippocampal-avoidance whole brain radiation therapy (HA-WBRT) by using the Elekta Monaco radiation therapy planning system (RTPs). For coplanar VMAT, both the arc per beam (APB) method and the beam determined arc(BDA) method, which is determined by the number of beams, were applied. For non-coplanar VMAT, the BDA method was utilized, and a total of 9 treatment plans were established by varying the arc counts. All radiation therapy plans met the radiation oncology group (RTOG) 0933 protocol standards, and 14 dosimetric factors were compared and analyzed. The results showed that the BDA-NC VMAT method demonstrated superior performance in terms of planning target volume (PTV) coverage and protection of normal organs, while APB-VMAT was advantageous in terms of hippocampal protection, monitor unit and delivery time. This study is expected to contribute to the efficient establishment of HA-WBRT plans considering the changes in beam arrangement and rotation arc numbers in Monaco RTPs.

• Journal of Preventive Medicine and Public Health
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• v.32 no.1
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• pp.9-16
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• 1999

Objectives. Few studies have attempted to explain the association between socioeconomic status (SES) and obesity in Korea Especially the studies on same race with different SES at same time are good for SES influence estimation. The present study highlights the influence of SES of parents on adolescent obesity. The subjects are the same race, but live in different areas, with different SES, Seoul and Yangpung in Korea, and Yanbian in China. Methods. The cross-sectional study was conducted in Mar-Jun 1996. We carried out anthropometry, 24 hour-recall diet survey, self-reported questionnaire about sociodemographic characteristics and physical activity. For SES indicators, we used income and education of parents. Results. The relationship between SES of parents, defined as educational status, and obesity in boys in Korea and China is direct, but not significant. The relationship is inverse and nonsignificant among Korean girls, However, for the Korean girls in severe obesity, the relationship is significant. For the Korean-Chinese girls, there is an inverse relationship between the education level and obesity but a direct relationship between the income level of parents and obesity. For the Korean adolescent, there are a direct association between the SES of parents and the nutrients factors such as energy, protein, and fat intake. The energy expenditure of adolescent has no relationship with SES of parents. Conclusion. Among boys, the higher the SES, the greater the risk of obese. Among girls in Korea and Korean-Chinese, on the other hand, the lower the educational status of parents, the greater the risk of obese.

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.258-264
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• 2007

Spatiotemporal changes of brain rhythmic activity at a certain frequency have been usually monitored in real time using scalp potential maps of multi-channel electroencephalography(EEG) or magnetic field maps of magnetoencephalography(MEG). In the present study, we investigate if it is possible to implement a real-time brain activity monitoring system which can monitor spatiotemporal changes of cortical rhythmic activity on a subject's cortical surface, neither on a sensor plane nor on a standard brain model, with a high temporal resolution. In the suggested system, a frequency domain inverse operator is preliminarily constructed, considering the individual subject's anatomical information, noise level, and sensor configurations. Spectral current power at each cortical vertex is then calculated for the Fourier transforms of successive sections of continuous data, when a single frequency or particular frequency band is given. An offline study which perfectly simulated the suggested system demonstrates that cortical rhythmic source changes can be monitored at the cortical level with a maximal delay time of about 200 ms, when 18 channel EEG data are analyzed under Pentium4 3.4GHz environment. Two sets of artifact-free, eye closed, resting EEG data acquired from a dementia patient and a normal male subject were used to show the feasibility of the suggested system. Factors influencing the computational delay are investigated and possible applications of the system are discussed as well.

• Atmosphere
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• v.24 no.1
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• pp.101-110
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• 2014

This study estimates and evaluates the daily January temperature from 2003 to 2012 with 30 m-resolution over South Korea, using a modified Parameter-elevation Regression on Independent Slopes Model (K-PRISM). Several factors in K-PRISM are also adjusted to 30 m grid spacing and daily time scales. The performance of K-PRISM is validated in terms of bias, root mean square error (RMSE), and correlation coefficient (Corr), and is then compared with that of inverse distance weighting (IDW) and hypsometric methods (HYPS). In estimating the temperature over Jeju island, K-PRISM has the lowest bias (-0.85) and RMSE (1.22), and the highest Corr (0.79) among the three methods. It captures the daily variation of observation, but tends to underestimate due to a high-discrepancy in mean altitudes between the observation stations and grid points of the 30 m topography. The temperature over South Korea derived from K-PRISM represents a detailed spatial pattern of the observed temperature, but generally tends to underestimate with a mean bias of -0.45. In bias terms, the estimation ability of K-PRISM differs between grid points, implying that care should be taken when dealing with poor skill area. The study results demonstrate that K-PRISM can reasonably estimate 30 m-resolution temperature over South Korea, and reflect topographically diverse signals with detailed structure features.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1261-1264
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• 2016

Background: In breast cancer (BC), it has been suggested that nuclear overexpression of p53 protein might be an indicator of poor prognosis. The aim of the current study was to evaluate the expression of p53 BC in Kurdish women from the West of Iran and its correlation with other clinicopathology figures. Materials and Methods: In the present retrospective study, 231 patients were investigated for estrogen receptor (ER) and progesterone receptor (PR) positivity, defined as ${\geq}10%$ positive tumor cells with nuclear staining. A binary logistic regression model was selected using Akaike Information Criteria (AIC) in stepwise selection for determination of important factors. Results: ER, PR, the human epidermal growth factor receptor 2 (HER2) and p53 were positive in 58.4%, 55.4%, 59.7% and 45% of cases, respectively. Ki67 index was divided into two groups: 54.5% had Ki67<20% and 45.5% had Ki67 ${\geq}20%$. Of 214 patients, 137(64%) had lymph node metastasis and of 186 patients, 122(65.6%) had vascular invasion. Binary logistic regression analysis showed that there was inverse significant correlation between lymph node metastasis (P=0.008, OR 0.120 and 95%CI 0.025-0.574), ER status (P=0.006, OR 0.080, 95%CI 0.014-0.477) and a direct correlation between HER2 (P=005, OR 3.047, 95%CI 1.407-6.599) with the expression of p53. Conclusions: As in a number of studies, expression of p53 had a inverse correlation with lymph node metastasis and ER status and also a direct correlation with HER2 status. Also, p53-positivity is more likely in triple negative BC compared to other subtypes.

• Korean Journal of Community Nutrition
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• v.16 no.3
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• pp.315-323
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• 2011

There are a few studies that reported the association of sleep duration with calorie intake and energy expenditure. Using cross-sectional data from a population-based prospective study, we evaluated the association of sleep duration with indicators of obesity including body mass index and waist circumference, calorie intake and its proportion of macronutrients, and physical activity. The study subjects were 4,226 male and female adults, who were aged 40 to 69 years and were free of diagnosed cardiovascular disease, diabetes mellitus, and dyslipidemia at baseline. Robust regression analysis was used to analyze associations. The study found that sleep duration is inversely associated with waist circumference, calorie intake, and percent of calories from fat intake and is positively associated with percent of calories from carbohydrate intake and physical activity. The inverse association between sleep duration and waist circumference was stronger among men than among women. The inverse association between sleep duration and calorie intake was stronger among women than among men and such association was also stronger among obese persons than those with a normal body mass index. The positive association between sleep duration and physical activity was strongly demonstrated regardless of sex or obesity. Physical activity is positively associated with sleep duration independent of potential confounding factors including age, sex, income, occupation, marital status, education, smoking status, waist circumference, calorie and macronutrient intake, and alcohol intake.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.2
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• pp.124-132
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• 2022

This study was aimed to visualize the spatial distribution of PM₁₀ data measured at non-uniformly distributed observation sites in South Korea. Different spatial interpolation methods were applied to irregularly distributed PM₁₀ observation data from January, 2019, when the concentration was the highest and in July, 2019, when the concentration was the lowest. Four interpolation methods with different parameters were used: Inverse Distance Weighted (IDW), Ordinary Kriging (OK), radial base function, and scattered interpolation. Six cases were cross-validated and the normalized root-mean-square error for each case was compared. The results showed that IDW using smoothing-related factors was the most appropriate method, while the OK method was least appropriate. Our results are expected to help users select the proper spatial interpolation method for PM₁₀ data analysis with comparative reliability and effectiveness.

• Clinical Nutrition Research
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• v.13 no.3
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• pp.165-175
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• 2024

This study aimed to assess the relationship between serum levels of vitamin D with anthropometric indices, lipid profile and vascular inflammatory factors, in patients who candidate for coronary artery bypass grafting (CABG). This analytical cross-sectional study was conducted in patients who were candidate for CABG. Demographic information, medical records, anthropometric indicators, blood samples, and physical activity of 150 patients were collected. 146 participants with mean ± standard deviation of age: 61.8 ± 10.0 years and body mass index: 26.9 ± 3.7 kg/m² completed the study. Based on serum levels of vitamin D, patients were divided into 2 groups; groups with sufficient (≥ 30 ng/mL) and insufficient amount of vitamin D (< 30 ng/mL). The 30.14% of the patients had serum vitamin D deficiency. Ejection fraction (EF) % between the 2 groups had significant difference. Unexpectedly the EF% increased 7% in patients with insufficient level of vitamin D (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.03-1.11; p = 0.001). Vitamin D status had a significant inverse association with body weight. The odds of vitamin D deficiency significantly increased by 4% with increasing one kg in weight (OR, 1.04; 95% CI, 1-1.08; p = 0.044). There were no significant association between serum vitamin D level and intra cellular adhesion molecule-1, interleukin-17, fasting blood glucose, and lipid profile (p > 0.05). Considering the inverse association observed between serum vitamin D with EF% and body weight, vitamin D may play a role in modulating of these indices.

• Environmental Analysis Health and Toxicology
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• v.20 no.2 s.49
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• pp.97-108
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• 2005

This study is to estimate differences, relationships and related factors of environmental risk perception and perceived benefit among residents and workers. A self-administered questionnaire survey using a structured instrument was carried out to residents and workers in industrial area during April, 2002. Total number of participants were 657 including 329 residents and 328 workers. Participants assessed environmental risk perception, self- assessed knowledge, trust in authorities and perceived benefit associated with 10 products manufactured in industrial area. There were difference in environmental risk perception, knowledge and trust in authorities and perceived benefit among residents and workers. Especially, trust in authorities and perceived benefit were statistically significant difference among residents and workers. Inverse relationships between environmental risk perception and perceived benefit have been observed for different products. In other words, the greater the perceived benefit, the lower the perceived risk, and vice versa. Factors mostly associated with participant's characteristics of environmental risk perception were age. marriage status (workers), education level (workers). There was statistically significant difference. Perceived benefit was statistically significant difference with sex, marriage status, residence duration, education level (workers). Related factors of environmental risk perception among residents and workers were age, trust in authorities. And factors affecting the perceived benefit were sex, age, education level (workers), and trust in authorities (workers). According to the results, people having high trust in the authorities perceived less risks than people having low in the authorities. To improve the communication of risk information, further study focus on assessment of experts, government and stakeholder in industrial area. Methodologies of this study can be used as the basis for investigating the structure of public perception of environmental products risks and benefit, designing a public information and risk communication program, and developing policy actions to improve acceptance.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4131-4136
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• 2016

Background: The population in northeast Thailand continues to present with hepatobiliary abnormalities, particularly periductal fibrosis (PDF) which is the result of chronic infection with liver fluke (Opisthorchis viverini; OV) and may lead to the development of cholangiocarcinoma (CCA). Although the prevalence of OV infection has been decreased due to a liver fluke control program over decades, the prevalence of PDF remains high. This study aimed to investigate demographic factors associated with PDF risk based on ultrasonography (US) screening. Materials and Methods: This cross-sectional study is part of the Cholangiocarcinoma Screening and Care Program (CASCAP), a prospective cohort study. Multiple logistic regression was used for data analysis. Results: In 55,246 subjects, the overall prevalence of PDF was 33.0% (95%CI: 32.6 - 33.4). Males (33.9 %) were at higher risk for developing PDF than females (32.2 %) (ORcrude = 0.93; 95%CI: 0.89 - 0.96; p-value < 0.001). Factors associated with an increased PDF risk, in addition to OV infection, included old age (${\geq}70$ years) (ORadj = 1.28, 95% CI: 1.14 - 1.44, p < 0.001) and hepatitis B infection (ORadj = 1.31, 95% CI: 1.11 - 1.55, p = 0.001). In contrast, number of praziquantel treatments (> 2 times) (ORadj = 0.54, 95% CI: 0.47 - 0.63, p < 0.001) and diabetes mellitus (ORadj = 0.57, 95% CI: 0.49 - 0.65, p < 0.001) were significantly associated with a decreased PDF risk. Conclusions: Future US screening should closely examine older people and hepatitis B subjects for the purpose of PDF surveillance among high risk groups for CCA. However, the results of inverse associations require further investigation in order to confirm our findings.