• Resources Recycling
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• v.29 no.6
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• pp.27-34
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• 2020

In order to remove sulfate(SO42-) and purify the Li2CO3, dissolution and recrystallization of crude Li2CO3 using distilled water and HCl solution was performed. When Li2CO3 was dissolved using distilled water, the amount of dissolved Li2CO3(wt.%) increased as the solution temperature decrease and showed about 1.50 wt.% at 2.5℃. In addition, when Na2CO3 was added and the Li2CO3 solution was recrystallized, the recrystallization(%) increased with increasing temperature, resulting in a 49.00 % at 95 ℃. On the other hand, when Li2CO3 was dissolved using HCl solution, there was no effect of reaction temperature. As the concentration of HCl solution increased, the amount of dissolved Li2CO3(wt.%) increased, indicating 7.10 wt.% in 2.0 M HCl solution. When the LiCl solution was recrystallized by adding Na2CO3, it exhibited a recrystallization(%) of 86.10 % at a reaction temperature of 70 ℃, and showed a sulfate ion removal(%) of 96.50 % or more. Finally, more than 99.10 % of Na and more than 99.90 % of sulfate were removed from the recrystallized Li2CO3 powder through water washing, and purified Li2CO3 with a purity of 99.10 % could be recovered.

• Journal of radiological science and technology
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• v.44 no.6
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• pp.671-677
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• 2021

Interest in the everyday hazards of radon has recently increased as such, this study attempted to examine the dangers of radon in spilled groundwater by comparing the radon concentrations of the drained groundwater and tap water used in recirculating systems in Incheon Subway restrooms. At five stations of Incheon Subway Line 1 and three stations of Line 2, drained groundwater is recirculated and used in restrooms for toilet flushing. Stations restroom tap water for hand washing that used as a control and the measured values of each were compared. With the cooperation of Incheon Transportation Corporation, samples of spilled groundwater and tap water were collected sealed to prevent contact with the air, and a DURRIDGE RAD7 was used as the experimental equipment. The collected samples were subjected to radial equilibration for approximately 3.5 h, at which the radon concentration reached its maximum, and then calculated as 10 measurements using the RAD7 underwater radon measurement mode. In all eight stations, the radon concentration in tap water was lower than the recommended amount. However, in an average of 7 out of the eight stations, the radon concentration in the effluent groundwater was 100 times higher than that in tap water. Since high radon concentrations in groundwater runoff can be harmful to humans, and there is no accurate standard for radon concentrations in domestic water, it is necessary to continuously monitor radon in water and prepare a guidance of recommended values.

• Journal of Nutrition and Health
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• v.56 no.3
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• pp.277-287
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• 2023

Purpose: This study was conducted to investigate the eating behavior (EB) and nutritional status of university students in Gwangju, and to compare their nutrition quotients (NQs) and problems according to their EB types. Methods: The subjects were 219 (127 female and 92 male) undergraduate students from Gwangju. The Student's t-test was used to compare the EB levels according to gender, and Pearson's χ² test was used to compare the distribution of EB types by gender. A gender-adjusted analysis of covariance (ANCOVA) was conducted to examine the difference in NQs by EB types. Results: First, there were significant differences in the EB scores and the distribution of EB types according to gender. Female students showed higher levels of emotional (Emo) and external (Ext) EBs than the male students, and Emo, Ext, and combined (Com) EB types were more evident among female rather than male students. Second, there was a difference in NQs according to the EB types. The Emo EB type subjects had a lower NQ than those of the restrained (Res) EB type and showed significant differences in diversity and dietary behavior. Specifically, the Emo EB type subjects displayed significantly lower efforts to maintain a healthy diet and subjective health status than the Com EB type and their levels of checking nutrition labels, hand washing, and water intake were significantly lower than that of the Res EB type. The Ext EB type showed significantly lower moderation of Ramyeon and sweetened drink intake than the Res and Com EB types. Conclusion: The level of EBs and the distribution of EB types varied according to gender, and the NQs were different according to EB types. The results of this study are expected to contribute to the establishment of customized strategies for improvement by identifying major nutritional problems by gender and the EB types of university students.

• Korean Journal of Community Nutrition
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• v.28 no.6
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• pp.509-522
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• 2023

Objectives: This study is intended to develop a curriculum for kindergarten food and nutrition education aimed at preschool children, reflecting government policy and meeting the demands of preschool settings. Methods: Existing educational materials were analyzed, and key elements of the 2019 Revised Nuri Curriculum ("Nuri Curriculum") and Guidelines for Nutrition and Food Education in Kindergartens, Elementary, Middle, and High Schools ("Guidelines") were examined as foundational information for developing the curriculum for food and nutrition education. Results: Basing ourselves on the five domains of the Nuri Curriculum, "Physical Activity and Health," "Communication," "Social Relationships," "Art Experience," and "Natural Science Inquiry," we integrated three areas from the Guidelines, namely "Dietary Habits and Health," "Dietary Habits and Safety," and "Dietary Habits and Culture," to structure the curriculum for kindergarten food and nutrition education. Three specific domains, "Nutrition and Health," "Food and Culture," and "Safe Dietary Practices," were tailored for preschool children, each comprising core concepts, content elements, and educational materials. In the "Nutrition and Health" domain, core concepts such as "nutrition" were addressed through content elements such as "balanced eating" and "vegetables and fruit," while "health" included elements such as "eating regularly" and "nutrients for disease prevention," each with two educational content components. The "Food and Culture" domain focused on "food" with content on "local foods (vegetable-garden experience)" and "food culture" with content on "our dining table (rice and side dishes)," "our agricultural products," "global cuisine (multiculture)," and "considerate dietary practices," each with four educational content components. The "Safe Dietary Practices" domain included core concepts such as "hygiene" with content on "hand-washing habits" and "food poisoning management," and "safety" with content on "food labeling." Conclusions: The systematized curriculum for kindergarten food and nutrition education aligns with the Nuri Curriculum and is interconnected with the Guidelines. This curriculum can be used as foundational material for developing educational resources tailored to the characteristics of preschoolers, contributing to effective implementation in early childhood education.

• Conservation Science in Museum
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• v.30
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• pp.1-22
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• 2023

This study aims to document the conservation treatment of the fine-hemp official headgear housed by the National Museum of Korea, and to reconsider its existing name following the restoration of the original form of the damaged cultural heritage asset. The headgear consists of a single inner frame with a vertical line at the front, a single outer frame surrounding the inner frame, and a double-layered headband that spans the circumference of the wearer's head and joins the inner and the outer frames. This study applied a conservation treatment to the men's undyed hemp headgear of the Joseon Dynasty in order to remove contaminants and foreign substances on the surface and repair the partially deteriorated and damaged fabric, thereby restoring and stabilizing the original shape and preparing it for exhibitions. The hemp headgear was sewed both by hand and with a sewing machine. Although its overall composition and style are similar to the same type of official headgear from the Joseon Dynasty, the use of a sewing machine supports the assumption that it was produced in the early 1900s. This study identified similarities between the overall composition and shape of the fully-preserved hemp official headgear and those of the jangbogwan, a type of men's official headgear worn by Confucian scholars as part of their everyday attire, and compared it with the shape of jangbogwan seen in documentary records, illustrations, prior research, and portraits from the Joseon Dynasty, as well as with the characteristics of extant jangbowan artifacts, eventually concluding that it is appropriate to classify and name the headgear as a jangbogwan.

• Journal of the Health Care and Life Science
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• v.10 no.1
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• pp.89-98
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• 2022

This study conducted a survey using a Google questionnaire targeting 380 male and female college students to find out the perceptions of college students about health masks at the time of transition from the COVID-19 pandemic to the recovery stage. As a result, at the time when the obligation to wear an outdoor mask was relaxed, they still wore an outdoor mask (3.63±1.34). As for the reasons for wearing a mask, 27.8% said 'wearing a mask became a habit' and 'fear of infection' was 19.4%. Hand washing to prevent COVID-19 was observed well (4.07±1.00), and when infection was suspected, they showed an attitude of checking for infection with a home kit or rapid antigen test (3.88±1.17). In addition, it was recognized that COVID-19 is not threatening (3.19±1.28) and that it will recover easily after infection (3.19±1.28). In a situation where the number of COVID-19 infections continues to decrease, the government is pushing for a gradual recovery of new daily life. Therefore, it is necessary to provide correct information that affects individual awareness and to promote it through various media, and I would like to emphasize the importance of education on the autonomous practice of individual quarantine rules.

• The Korean journal of internal medicine
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• v.39 no.3
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• pp.513-523
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• 2024

Background/Aims: Since the coronavirus disease 2019 (COVID-19) outbreak, hospitals have implemented infection control measures to minimize the spread of the virus within facilities. This study aimed to investigate the impact of COVID-19 on the incidence of healthcare-associated infections (HCAIs) and common respiratory virus (cRV) infections in hematology units. Methods: This retrospective study included all patients hospitalized in Catholic Hematology Hospital between 2019 and 2020. Patients infected with vancomycin-resistant Enterococci (VRE), carbapenemase-producing Enterobacterales (CPE), Clostridium difficile infection (CDI), and cRV were analyzed. The incidence rate ratio (IRR) methods and interrupted time series analyses were performed to compare the incidence rates before and after the pandemic. Results: The incidence rates of CPE and VRE did not differ between the two periods. However, the incidence of CDI increased significantly (IRR: 1.41 [p = 0.002]) after the COVID-19 pandemic. The incidence of cRV infection decreased by 76% after the COVID-19 outbreak (IRR: 0.240 [p < 0.001]). The incidence of adenovirus, parainfluenza virus, and rhinovirus infection significantly decreased in the COVID-19 period (IRRs: 0.087 [p = 0.003], 0.031 [p < 0.001], and 0.149 [p < 0.001], respectively). Conclusions: The implementation of COVID-19 infection control measures reduced the incidence of cRV infection. However, CDI increased significantly and incidence rates of CPE and VRE remained unchanged in hematological patients after the pandemic. Infection control measures suitable for each type of HCAI, such as stringent hand washing for CDI and enough isolation capacities, should be implemented and maintained in future pandemics, especially in immunocompromised patients.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.247-257
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• 2014

Assessment for operator's dermal and inhalation exposure to acetamiprid during cultivation of water melon in greenhouse was carried out. For dermal exposure measurement, whole body dosimetry (WBD) was performed as the first trial in Korea. WBD consists of cotton/polyester outer clothes and cotton inner clothes. Hand exposure was measured by washing of nitrile gloves and hands while head exposure was monitored by face/neck wipe technique. Inhalation exposure was monitored with personal air sampling pumps and IOM sampler (glass fiber filter). Analytical limit of quantitation was 2.5 ng/mL. Good reproducibility (C.V < 8.7%), linearity ($R^2$ > 0.99) and recovery (70~119%) were obtained. Field recovery of acetamiprid was 77~95%. During mixing/loading, hand exposure of acetamiprid was about 10 times ($229.7{\mu}g$) more than that of application case ($20.9{\mu}g$). During application, total dermal exposure was $1207.4{\mu}g$. Exposure of lower legs was $1132.1{\mu}g$, which is 93.8% of the total dermal exposure. Inhalation exposure during mixing/loading and application was not detected. Margin of safety (MOS) was calculated for risk assessment using male Korean average body weight (70 kg) and acceptable operator exposure level ($124{\mu}g/kg/day$) to give 140, suggesting that health risk of operator during treatment of acetamiprid for water melon in greenhouse could be safe.

• Journal of dental hygiene science
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• v.7 no.2
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• pp.101-106
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• 2007

This research was based on self-filling survey which 128 dental hygienists who work in dental clinic and dental hospital on May 2006 through July 2006. This survey was analyzed the prevention against virus infection in dental hygienist at medical treatment. As follows analyzed results The experience of get a hand pricked by an infected needle rate is 76.6 percent and the majority of the dental hygienist are sterilize by disinfectant after wash hand and draw blood. The most of dental hygienist are experienced the education of the prevention infection in student and they think that It is necessary to prevention infection in medical treatment. The proportion of use the glove and mask in medical treatment and disuse the glove after medical treatment and the mask when mask get damped is high but the rate of put on the goggle in medical treatment and use the glove in washing and re-treat is low irrespective of age, clinical career, work place. As a result of Independent-sample T Test, the Hygienist who have experience the education of the prevention against virus infection are more excellent work than in-experience group in medical treatment. So we can find that the experience of the education of the prevention infection is very significant to prevention infection in dental hygienist.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.159-165
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• 2015

The aim of this study was to investigate microbiological contamination levels in the manufacturing company of ginseng products (white and red ginseng). Firstly, the contamination level for ginseng and each stage ginseng were 1.8~4.9 log CFU/g (total bacteria), 1.2~3.0 log CFU/g (coliform), 0.8~4.1 log CFU/g (fungi). However, only Bacillus cereus among pathogenic bacteria was detected from a few sample. The contamination of total bacteria tended to decrease as ginseng was being processing. Therefore, that of finished products (white and red ginseng) showed the lowest contamination level among each stage ginseng sample. That of fungi decreased steadily, although the contamination of fungi has tended to increase right after ginseng was steamed. Secondly, the contamination level for working tools and facilities were $1.7{\sim}4.7log\;CFU/cm^2$ (total bacteria), $0.4{\sim}4.0log\;CFU/cm^2$ (coliform), $0.9{\sim}4.2log\;CFU/cm^2$ (fungi). Especially, washing and peeling machines were higher contamination level. Finally, the contamination level of worker who washed and steamed ginseng was higher than worker who shaped, sorted and stored ginseng. Also, Staphylococus aureus was detected at 0.2~0.7 log CFU/hand on some wokers' hands. These results showed proper heating condition (temperature and time) and tidy manufacturing facility are the most important to avoid developing any microbiological problem of Ginseng Products.