• Reproductive and Developmental Biology
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• v.30 no.4
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• pp.247-253
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• 2006

Our previous research has identified granulin (grn) and p130 genes as sex steroid-inducible genes in the rat hypothalamus, which might be involved in sexual differentiation of the brain. Phthalate esters that are used as plasticizers and also found at low levels in foods such as dairy products are often mentioned as suspected endocrine disrupters. The purpose of the present study is to elucidate whether perinatal exposure to di-n-butyl phthalate (DBP), diisononyl phthalate (DINP) and di-2-ethylhexyl adipate (DEHA) affects hypothalamic sex steroid-inducible genes. The present study assessed the effects of perinatal exposure to DBP, DINP and DEHA on sex steroid hormones levels and hypothalamic gm and p130 mRNA expressions at postnatal day (PND) 3 and 7. Pregnant rats were fed a soy-free diet containing 20, 200, 2,000 and 10,000 ppm of DBP, 40, 400, 4,000 and 20,000 ppm of DINP, or 480, 2,400 and 12,000 ppm of DEHA from gestational day (GD) 15 to GD 3 or 7. At PND 3 and 7, perinatal exposure to these chemicals did not substantially affect serum concentrations of testosterone and estradiol. At PND 3, the expression of grn mRNA levels in males was decreased by DEHA, and that of p130 was decreased by DBP, DINP and DEHA, though the effects were not dose-dependent. At PND 7, the expression of gm gene in female pups was increased by higher doses of DBP and all the doses, except for 4,000 ppm, of DINP, while that in male pups decreased by 480 and 12,000 ppm of DEHA. Hypothalamic expression of p130 mRNA in males was increased by lower doses of DBP and all the doses of DINP, whereas that of females was decreased by 480 and 2,400 ppm of DEHA. These results suggest that these chemicals may affect the expression of gm and p130 genes by directly acting on the hypothalamus, thus leading to inappropriate expression of these genes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.64-72
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• 2015

Risk Based Inspection (RBI) Period was proposed for highway bridges in Korea. Hazard factors affecting bridge condition deterioration were found by analyzing condition data from Highway Bridge Management System (HBMS). Certain level of correlations between those factors and condition deterioration were found. They are used to evaluate hazard score. Summarizing several hazard factors, final hazard is classified as three level;high, moderate, low. Vulnerability is assessed only by the current state of bridge. Then, risk matrix is suggested for inspection periods. Inspection periods of the bridges with grade C, D, and E are maintained the same as before. But, those of grade A and B with moderate and high hazard score are elongated to maximum 6 years while the maximum inspection period is three years at present. By adjusting inspection period according to risk assessment, it was shown that 27% of average inspection manpower can be saved.

• Journal of the Korean earth science society
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• v.35 no.5
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• pp.313-323
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• 2014

We secured the high dispersion spectra of the symbiotic star CI Cyg. The HI, HeI, and HeII line profiles were analyzed using the relatively long exposure data including 1800 sec (Sep. 12, 1998, phase=0.90), 3600 sec (Aug. 12, 2002, ${\phi}=0.47$), and 1800 sec (Oct. 21, 2009, ${\phi}=0.54$). Although a minor outburst was reported in 2008, our three observation periods were generally known to be quiescent in earlier photometric studies. With the help of hydrodynamic simulations, we identified the two emission zones responsible for the blue- and red-shifted line components: (a) an accretion disk around a hot white dwarf star which consists of the outer cool HeI emission zone and the inner hot HeII emission part, and (b) a high density zone near the inner Lagrangian point responsible for the HeI line flux variation and the broadening of its line profile. The HeII line fluxes indicate that the HeII emission zone of the accretion disk is relatively stable, implying a constant gas inflow from the giant star throughout the quiescent period. The 2002 HeI data showed that the notable mass flow activity through the inner Lagrangian point occurred during this period and its flux intensity became strongest, whereas the HeII line width in the same period indicates that its flow activity forced the accretion disk to expand. The [OIII] lines were observed in 1998 but not detected in 2002 and 2009, implying the disappearance of the low density zone. Based on our kinematical studies upon the line profiles, we conclude that CI Cyg was stable in 1998 among the three observation periods selected in this research.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.382-396
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• 2008

The purpose of this study is to analyze the transition of glamour style expressed in modern fashion throughout the history. The glamour style in modern fashion was categorized into five periods which are Hollywood glamour(H), Feminine glamour(F), Rich glamour(R), Decadent glamour(D), and Trash glamour(T). These categories were analyzed and compared in the viewpoint of aesthetic values deduced on the previous study. As a method of analysis, literature study and case study through the publications in aesthetics, history and preceding theses were used. The results of analysis are: Ostentatious luxury was suggested by extravagance of the movie star in H, the splendid American lifestyle in F, conspicuous consumption in R, fin de siecle bad taste in D and self-assured exposure in T. Mysterious idolatry was studied as exaggerated goddesshood of the movie star in H. It was expanded to celebrities including fashion models, television actresses, pop singers and young couture designers in the other periods. Artificial sensuality was originated from the femme fatale image of the courtesan as well as the traditional femininity of Victorian era in H. It was developed through exaggerated hourglass silhouette of the wife dressing in F. But an aggressiveness in R, a hyper-sexual femme fatale in D, an independent and defiant image of the showgirl in T were observed. Playful queerness stood out clearly by the fin de siecle phenomena. Though it was embodied in sexual perversive subculture, it emerged as hi fashion by young designers in the late R and became a crucial aesthetic value throughout D and T. It is more connected with the origins of glamour which arouses sexual ambiguity, crudity, aggressiveness and death. The continuity and discontinuity of the glamour style based on the theory of 'linked solution' were also analyzed.

• Journal of Preventive Medicine and Public Health
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• v.45 no.1
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• pp.47-59
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• 2012

Objectives: This study was conducted to observe recent changes in adolescents' dietary behavior and indirectly evaluate the effects of the government's nutritional policies in Korea. Methods: We analyzed the secular trends in seven dietary behaviors using the Korea Youth Risk Behavior Web-based Survey data from 2005 to 2009. Through literature review, we included the policies implemented for the improvement of adolescents' dietary behaviors during the same periods. Results: The significant linear trends were observed in all dietary behaviors (p<0.05). Overall, all behaviors except the fruit intake rate were desirably changed during five years but undesirable changes were observed between 2008 and 2009 in all behaviors. Within those periods, several policies were implemented including 'Ban on carbonated-beverages in school', 'Green Food Zone', etc. Despite confirmed evidence of their effects, the policies on individual behavior such as nutrition education didn't influence the prevalence of dietary behaviors because they were conducted to too limited persons. Polices on the school environmental improvement, such as ban on carbonated beverage in school, were more effective because they decreased the exposure of undesirable food environment. However, for effect of Green Food Zone improving community environment we couldn't come to a conclusion because of too short period after full implementation. Conclusions: Among government nutrition policies conducted from 2005 to 2009, those on environmental improvement, especially in school, were more effective than those on individual behavior. Therefore, the development and implement of policies on school environmental improvement are needed in Korea.

• Journal of Preventive Medicine and Public Health
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• v.51 no.6
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• pp.281-288
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• 2018

Objectives: We investigated the association between cholecystectomy or appendectomy and the subsequent risk of colorectal cancer (CRC) in the Korean population. Methods: A retrospective cohort study was conducted with the National Health Insurance Service-National Sample Cohort of Korea; this sample was followed up from January 1, 2002, until the date of CRC incidence, loss to follow-up, or December 31, 2015. The exposure status of cholecystectomy and appendectomy was treated as a time-varying covariate. The calculated risk of CRC was stratified by follow-up period, and the association between these surgical procedures and CRC was investigated by a Cox regression model applying appropriate lag periods. Results: A total of 707 663 individuals were identified for analysis. The study population was followed up for an average of 13.66 years, and 4324 CRC cases were identified. The hazard ratio (HR) of CRC was elevated in the first year after cholecystectomy (HR, 1.71; 95% confidence interval [CI], 1.01 to 2.89) and in the first year and 2-3 years after appendectomy (HR, 4.22; 95% CI, 2.87 to 6.20; HR, 2.34; 95% CI, 1.36 to 4.03, respectively). The HRs of CRC after applying 1 year of lag after cholecystectomy and 3 years of lag after appendectomy were 0.80 (95% CI, 0.57 to 1.13) and 0.77 (95% CI, 0.51 to 1.16), respectively. Conclusions: The risk of CRC increased in the first year after cholecystectomy and appendectomy, implying the possibility of bias. When appropriate lag periods after surgery were applied, no association was found between cholecystectomy or appendectomy and CRC.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.4
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• pp.325-339
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• 2022

Objective: This study was to perform to identify the distribution characteristics and related factors of work-related low back pain among manufacturing workers in Korea. Methods: We analyzed the third(2011) through sixth(2020) Korean Working Conditions Survey. This study examined changes in the prevalence of work-related low back pain among manufacturing workers and related factors, including demographic characteristics and working conditions. Results: The prevalence of work-related low back pain showed a general tendency to increase during the study periods except for the 5th wave. The prevalence of work-related low back pain was higher in women than in men. The prevalence increased with increasing age and decreased with higher educational attainment. This trend was observed in all survey waves. The prevalence ratios for work-related low back pain according to working conditions varied over the survey period. In general, workers with manual jobs, long working hours, and exposure to tired or painful postures showed relatively higher prevalence ratios than did their counterparts. Providing Information on health and safety, perception that work affects health, and experience of presenteeism were identified as influencing factors for work-related low back pain. Although the working environment is improving, work-related back pain is on the rise. A multifaceted study on risk factors for work-related low back pain is needed. Conclusion: Work-related low back pain is a significant factor affecting the working population's quality of life. The prevalence of work-related low back pain showed a tendency to increase during the study periods. A multifaceted study on risk factors for work-related low back pain is needed.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.46.3-47
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• 2020

Variations in the brightness of asteroids are caused by their spins, irregular shapes and companions. Thus, in principle, the spin state and shape model of a single object or, a combined model of spins, shapes and mutual orbit of a multiple components can be constructed from the analysis of light curves obtained from the time-series photometry. Using ground- and space-based facilities, a number of time-series photometric observations of asteroids have been conducted to find the possible causes of their light variations. Nonetheless, only about 2% of the known asteroids have been confirmed for their rotation periods. Therefore, a follow-on systematic photometric survey of asteroids is essential. We started an asteroid light curve survey for this purpose using Korea Microlensing Telescope Network (KMTNet) during 199 nights between the second half of 2019 and the first half of 2020. We monitored within a 2° × 14° region of the sky per each night with 25 min cadences. In order to observe as many asteroids as possible with a single exposure, we mostly focus on the ecliptic plane. In our survey, 25,925 asteroids were observed and about 8,000 of them were confirmed for their rotation periods. In addition, using KMTNet's 24-hour continuous monitoring, we collected many composite light curves of slow rotating asteroids that were rarely obtained with previous observations. In this presentation, we will introduce the typical light curves of asteroids obtained from our survey and present a statistical analysis of spin states and shapes of the asteroids from this study.

• Journal of Society of Preventive Korean Medicine
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• v.28 no.1
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• pp.69-87
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• 2024

Objectives : This study is to investigate the current National Health Insurance Database cohort studies related to complications of Parkinson's Disease (PD) and suggest the design of Korean medical epidemiological studies of PD. Methods : Nationwide longitudinal studies of PD patients in South Korea were collected through Pubmed and the Korea Citation Index (KCI). We selected cohort studies that used the National Health Insurance Database in Korea and targeted Parkinson's disease patients. Studies published before February 2024 were categorized according to study designs. We examined variables and covariates, enroll dates and matching methods. Results : Of a total of 536 studies, 18 studies met the inclusion criteria. All studies used the National Health Insurance (NHI) Research Database and among them, 5 used sample data and one senior database. Studies can be classified into two types. 11 cohort studies were comparing PD patients and non-PD patients. Another type was 4 PD patients cohort studies. Most studies used two diagnostic codes (G20 and V124) for inclusion criteria. Enroll periods were from 2002 to 2017, and follow-up periods were from 7 to 14 years. 16 studies considered age and sex as covariates. 15 studies used the propensity score matching method to increase the level of causality. There was only one study related to the Korean medical treatment. Conclusion : In future cohort studies on Korean medical treatment, more attempts should be made to reveal the effect of the treatments on PD patients by defining inclusion criteria for patient groups, covariates, exposure variables, and assessment indicators more operatively.

• Journal of Preventive Medicine and Public Health
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• v.23 no.1 s.29
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• pp.77-86
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• 1990

Between 1977 and 1987, 20 patients with mesothelioma were treated at Severance Hospital. Data was gathered from medical charts at the time of hospitalization of mesothelioma patients and from a follow-up questionnaire by mail or telephone. The results acquired were as follows : 1. Among the 20 patients, 11 men and 9 women with mesothelioma were identified. The mean age at hospitalization was 47 years and 11 mesothelioma patients were known or presumed to be dead during the different observation periods. 2. Only one mesothelioma patient had a definite history of occupational asbestos exposure. 3. The sites of origin of mesothelioma were the pleura(13), peritoneum(2), pericardium(2), mediastinum (2), and pelvis(1). Common symptoms included dyspnea, chest pain, abdominal distension, etc. 4. Pathologically, mesotheliomas were divided into 14 malignant types and 6 benign types ; and histologically, 8 fibrous mesotheliomas and 3 epithelial mesotheliomas were shown. 5. There was a statistically significant difference in survival rate according to pathologic type and smoking status. In the groups with malignant mesothelioma, 50% survival time from first symptoms was 18 months and that from diagnosis was 11 months. Also, 75% survival time from diagnosis was 6 months in the smoking groups and 19 months in the non-smoking groups.