• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.59-67
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• 2023

Background: This study aims to reevaluate natural radiation exposure, following up on our previous study conducted in 2019, and to assess the associated risk of lung cancer to the public residing in the gold mining areas of Betare-Oya, east Cameroon, and its vicinity. Materials and Methods: Gamma-ray spectra collected using a 7.62 cm×7.62 cm in NaI(Tl) scintillation spectrometer during a car-borne survey, in situ measurements and laboratory measurements performed in previous studies were used to determine the outdoor absorbed dose rate in air to evaluate the annual external dose inhaled by the public. For determining internal exposure, radon gas concentrations were measured and used to estimate the inhalation dose while considering the inhalation of radon and its decay products. Results and Discussion: The mean value of the laboratory-measured outdoor gamma dose rate was 47 nGy/hr, which agrees with our previous results (44 nGy/hr) recorded through direct measurements (in situ and car-borne survey). The resulting annual external dose (0.29±0.09 mSv/yr) obtained is similar to that of the previous study (0.33±0.03 mSv/yr). The total inhalation dose resulting from radon isotopes and their decay products ranged between 1.96 and 9.63 mSv/yr with an arithmetic mean of 3.95±1.65 mSv/yr. The resulting excess lung cancer risk was estimated; it ranged from 62 to 216 excess deaths per million persons per year (MPY), 81 to 243 excess deaths per MPY, or 135 excess deaths per MPY, based on whether risk factors reported by the U.S. Environmental Protection Agency, United Nations Scientific Committee on the effects of Atomic Radiation, or International Commission on Radiological Protection were used, respectively. These values are more than double the world average values reported by the same agencies. Conclusion: There is an elevated level of risk of lung cancer from indoor radon in locations close to the Betare-Oya gold mining region in east Cameroon. Therefore, educating the public on the harmful effects of radon exposure and considering some remedial actions for protection against radon and its progenies is necessary.

• Journal of Korean Medicine Rehabilitation
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• v.33 no.3
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• pp.47-65
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• 2023

Objectives We evaluated the wound healing effects of Dangguijakyak-san (DJ) using C57BL/6 mice that were generated open wound. Methods The study was conducted with seven C57BL/6 mice assigned to each group, divided into the normal group, control group, vitamin E group, DJ low-dose group, DJ high-dose group. We measured total polyphenol, flavonoid contents, the size of the wound, liver function, pro-inflammatory cytokine activity in serum, inflammation-related proteins, adhesion molecules and chemokine proteins, collagen-related proteins in skin tissue and histopathological changes by H&E and Masson's staining. Results DJ treatment significantly reduced the area of the wound compared to the control group. Also, inflammatory cytokines were reduced and the expression of anti-inflammatory-related factors (interleukin-4 [IL-4] and IL-10) was significantly increased in the DJ treatment group. We identified that DJ treatment inhibits both pathways of inflammation, the mitogen-activated protein kinases and nuclear factor-κB pathway. Moreover, the protein expressions of Sirt1 (sirtuin 1), MCP-1 (monocyte chemoattractant protein 1), ICAM-1 (intercellular adhesion molecule 1), and VCAM-1 (vascular cell adhesion molecule 1) were decreased by DJ administration. Also, the expression of α-smooth muscle actin and collagen type I alpha 1, collagen-related proteins, that help skin recovery was significantly increased in the DJ treatment group. Histopathologically, a relatively thin epithelial layer could be observed in the DJ administration group, as well as an increase in fibroblasts and collagen fibers. Conclusions These data suggest that DJ treatment is effective in wound healing, suppressing inflammatory proteins, increasing skin repair factors and improving histopathological changes caused by wounds.

• Geomechanics and Engineering
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• v.34 no.4
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• pp.449-459
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• 2023

The design and development of underground nuclear waste repositories should cover the performance evaluation of the different components such as the construction materials because the long term stability will depend on their response to the surrounding conditions. In South Korea, Gyeonju bentonite has been proposed as a candidate to be used as buffer and backfilling material, especially in the form of blocks to speed up the construction process. In this study, various cylindrical samples were prepared with different dry density and water content, and their physical and mechanical properties were analyzed and correlated with X-ray CT observations. The main objective was to characterize the samples and establish correlations for non-destructive estimation of physical and mechanical properties through the utilization of X-ray CT images. The results showed that the Uniaxial Compression Strength and the P-wave velocity have an increasing relationship with the dry density. Also, a higher water content increased the values of the measure parameters, especially for the P-wave velocity. The X-ray CT analysis indicated a clear relation between the mean CT value and the dry density, Uniaxial Compression Strength, and P-wave velocity. The effect of the higher water content was also captured by the mean CT value. Also, the relationship between the mean CT value and the dry density was used to plot CT dry densities using CT images only. Moreover, the histograms also provided information about the samples heterogeneity through the histograms' full width at half maximum values. Finally, the particle size and heterogeneity were also analyzed using the Madogram function. This function identified small particles in uniform samples and large particles in some samples as a result of poor mixing during preparation. Also, the μ_max value correlated with the heterogeneity, and higher values represented samples with larger ranges of CT values or particle densities. These image-based tools have been shown to be useful on the non-destructive characterization of bentonite samples, and the establishment of correlations to obtain physical and mechanical parameters solely from CT images.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5A
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• pp.901-908
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• 2006

The structural integrity of containment building in Nuclear Power Plants has to be verified by the ISI(In Service Inspection) because there are some variations on the structural behavior of it due to the change of the physical properties of concrete and tendon with the lapse of time. In this study, the program 'SAPONC-CANDU' which can monitor and analyze the structural behavior of the containment building with grouted tendon (CANDU-type, 'Wolsong unit-2, 3, and 4' in Korea) was developed. This program is based on the algorithm which can calculate the prediction values of the quantities of strain variation for the vibrating-wire strain gauges embedded into the concrete of the containment building under temperature and time dependent factors which are creep, shrinkage, and prestressing force. The readings of the strain gauges are used as input data for the operation of the program. And it finally provides graphically a prediction value, line and band of the quantity of strain variation for the respective strain gauges, therefore, it is thought that the site engineers are able to assess the structural integrity of the domestic containment building with grouted tendon with easy using this program.

• Journal of the Korean Society of Food Culture
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• v.22 no.5
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• pp.633-644
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• 2007

The study results regarding the ingredient differences, sensory characteristics, purchasing type, usage and improvement direction for home-made traditional doenjang and factory produced commercial doenjang are as follows. The L-value indicates that home-made traditional doenjang has a higher value in average than the factory produce done, and the a-value indicates the opposite. Home-made traditional doenjang had higher water content than commercial doenjang ; however the pH values of commercial doenjang and home-made were 5.34 and 5.32 respectively, which was very similar. Factory produced commercial doenjang showed higher protein content than the home-made traditional doenjang. Regarding the correlation between ingredients, there was a significantly negative relationship between the L-value and a-value but a significantly positive relationship between the L-value and b-value. There were no significant relationship with water content, pH and protein content. For the color and taste, which are the sensory characteristics, commercial doenjang showed higher value than the traditional doenjang, but for smell, the values were similar. Regarding grittiness, the factory produced commercial doenjang had bigger particles than the traditional doenjang. Preference was a bit higher in the traditional doenjang. Of the 380 study subjects, most were from 40 to 49 years old (65.5%), and the most family type were nuclear families which was a total of 400 people (69%). Moreover, the most residential type was apartment which was 355people (61.2%), and for the monthly income, more than 2,510,000won was 48.3%. For the educational background, college education was 304 people (52.4%), and high school education was 199 people, 34.3%. In the usage, most of the people eat doenjang more than once a week, and usually their parents make the doenjang. People used both commercial doenjang and home-made traditional doenjang >home-made only >factory produced commercial doenjang only in that order. The reasons for using the home-made traditional doenjang aredelicate taste and flavor>more nutritious> anti-cancer ingredients in that order. The reason they use the factory produced commercial doenjang is because they don't know how to make it at home. The things that needed to be improved in the home-made traditional doenjang are bad smell> entire quality> flavor> color in order, indicating that studies for reducing bad smell are required. The things that needed to be improved in the factory produced commercial doenjang are taste & flavor> entire quality>bad smell> color in that order, indicating that people are more concern about it tasting like home-made than the smell. From the above results, we can see that better functional doenjang should be developed for family health and to increase the consumption of the doenjang, which has good functional psychological activities, also more various types of foods that use doenjang and scientific studies to reduce the home-made doenjang smell should be continuously studied. Moreover, studies on how to make the factory produced commercial doenjang taste more like traditional doenjang should be performed.

• Journal of the Korean Society of Food Culture
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• v.23 no.1
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• pp.1-9
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• 2008

This study aimed to offer some basic data for nutrition education to housewives by comparing behaviors of eating out targeted on housewives who live in Daejon surveyed by classification of regions and by family forms. As for their ages, 79 housewives (16.0%) are less than 30, 179 housewives (36.8%) are between 30 and 39, 156 housewives (35.9%) are between 40 and 49 and 74 housewives (15.2%) are more than 50, and as for their final academic careers, 204 housewives (41.9%) graduated from universities, which was the most and as for religions, 172 housewives (35.3%) had no religion, which was the most, and in the case that they had religions, 137 housewives (27.5%) believed in Christianity. And as for occupations, 327 housewives (69.0%) had no job, and in case they had jobs, 123 housewives (25.3%) that occupied the most were professional. As for husbands’ occupations, profession was the most for 143 housewives (29.4%) and as for monthly income, $2\; million\;won{\sim}3\;million$ won was most as 40.0%. As for times of eating out, ‘4 times a year’ was said by 131 housewives (26.9%), which was the most, and as for the times of food home service, ‘seldom’ was said by 221 housewives (45.4%), and as to the expense for eating out a month, ‘less than 100,000 won’ was said by 219 housewives (45.0%), which was the most, and as for the reasons of their eating out, ‘for harmony in a family’ was said by 119 housewives (24.4%). As for times of eating out by general items of housewives, it was appeared that the younger, the higher in education, less in religion, more in occupation, the more professional in their husbands’ jobs, the more nuclear in family forms, fewer in number of family members and the more average family income per a month, they had more times of eating out. Regarding the factors influencing on eating out, ‘high price’, ‘nutritive imbalance’ and ‘use of MSG’ were pointed by 204 housewives (41.9%), 83 housewives (17.0%) and 63 housewives (12.9%) respectively as the problems of food service shops. And as for the question why their went to their regular restaurants, 185 housewives (38.0%) said ‘taste of food’, and the most considerable thing when they selected menu at a restaurant was ‘taste of food’ for 167 housewives (34.3%). The survey showed that a lot of housewives thought the prices at restaurants were high, and they valued taste of food most, therefore food service shops should improve the taste and nutrition of food.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6A
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• pp.543-560
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• 2010

Safety-related concrete structures in a nuclear power plant must be protected against the impact of flying objects, referred to in the profession as missiles. In practice, the structural verification is usually carried out by means of empirical formulas, which relate the velocity of the impinging missile to the wall thickness needed to prevent scabbing or perforation. The purpose of this study is to reevaluate the predictability of the local effect prediction formulas for the penetration and scabbing depths and perforation thickness. Therefore, available formulas for predicting the penetration depth, scabbing thickness, and perforation thickness of concrete structures impacted by solid missiles are summarized, reviewed, and compared. A series of impact analyses is performed to predict the local effects of the projectile at impact velocities varing from 95 to 215 m/s. The results obtained from the numerical simulations have been compared with tests that were carried out at Kojima to validate numerical modelling. The simulation results show reasonable agreement with the Kojima test results for the overall impact response of the RC slabs. From these results, it seems that the Degen equation give a very good estimate of perforation thickness against a tornado projectile for test data. Finally, the results obtained from the impact analysis have been compared with Degen formula to determine the perforation thickness of the RC slab.

• Animal Bioscience
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• v.35 no.9
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• pp.1434-1443
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• 2022

Objective: This study was designed to investigate the hypothesis that dietary quercetin (QUE) and coated sodium butyrate (SB) supplementation alleviate oxidative stress in the small intestine of diquat (DIQ)-challenged pullets. Methods: A total of 200 13-week-old pullets were divided into four groups: the control group (CON), the DIQ group, the QUE group, and the coated SB group, and injected intraperitoneally with either saline (CON) or diquat (DIQ, QUE, and SB) to induce oxidative stress on day 0. Results: On the first day, the malondialdehyde and superoxide dismutase (SOD) concentrations in the SB group were significantly different from those in the DIQ and QUE groups (p<0.05), and dietary supplementation with SB increased serum glutathione peroxidase (GSH-PX) levels compared with the DIQ group (p<0.05). Quercetin and SB increased the levels of CLAUDIN-1 and zonula occludens-1 (ZO-1) in the jejunum. On the tenth day of treatment, QUE attenuated the decrease in GSH-PX levels compared to those of the CON group (p<0.05), while SB increased SOD, GSH-PX, and total antioxidant capacity levels compared to those of the DIQ group. Nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase-1 (HO-1) mRNA levels in the QUE and SB groups increased (p<0.05) and CLAUDIN-1 mRNA levels in the QUE and SB groups were upregulated compared to those in the DIQ group ileum tissue. Conclusion: Supplementation of QUE and SB demonstrated the ability to relieve oxidative stress in pullets post DIQ-injection with a time-dependent manner and QUE and SB may be potential antioxidant additives for relieving oxidative stress and protecting the intestinal barrier of pullets.

• Korean Journal of Social Welfare Studies
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• v.42 no.3
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• pp.267-290
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• 2011

This research attempts to analyze the effects of demographic factors, socioeconomic factors, health behaviors and social/familial supports on health inequalities among Korean elderly. For this end, this study adopts the multiple linear regression analysis to process data on population aged over 65 contained in 'The Third Korea Welfare Panel Study' published in 2008. The following are the results. First, the less educated they are, the smaller income they earn, the less they drink, the less satisfied with relationships with their family members, the more they turn out to feel depressed. Second, the less educated they are, the smaller income they earn, the less they drink, the less they are satisfied with relationship with family members, the more they benefit from social welfare services, the worse they turn out to rate their health. Based on these findings, three following suggestions could be forwarded. First, vulnerable aged groups including female elderly, low-income elderly, less-educated elderly need customized social supports. Second, new social policy for households is required to enhance elderly people's satisfaction with their family relationships with the rapid trend of a growing number of nuclear families and aging. Third, social welfare service programs need to be reevaluated to enhance their function for the aged.

• Journal of The Korean Ophthalmological Society
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• v.60 no.5
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• pp.480-485
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• 2019

Purpose: We report a case of postoperative endophthalmitis in the cataract patient, associated with removal of an intralenticular foreign body that had remained in place without symptoms for 20 years. Case summary: A 45-year-old male visited our outpatient clinic complaining of gradual visual loss in his right eye over the past 3 months. In slit-lamp examinations, anterior capsular opacification, nuclear sclerosis, and posterior subcapsular opacity were observed in the right eye. Twenty years before, a tiny metallic projectile had hit his right eye, but slit-lamp examination at the time of injury did not reveal any intraocular foreign body. We decided to undergo cataract surgery. During phacoemulsification, a metallic foreign body was found in the lens and safely removed; then an intraocular lens was implanted. As hypopyon was evident 3 days later, we injected intravitreal antibiotics and applied fortified antibiotic eye drops to the right eye. The anterior chamber inflammation improved and the best-corrected visual acuity recovered to 1.0. Conclusions: Surgeon should be aware of that endophthalmitis could develop after cataract surgery with removal of an intralenticular foreign body that had been in place for 20 years. But did not trigger inflammation or cause any symptoms as the cataract progressed.