• Korean Journal of Ecology and Environment
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• v.56 no.3
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• pp.207-217
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• 2023

This study was conducted to investigate the current status of seagrass species in the Nakdong River estuary from May to June 2023. To survey the seagrass habitat area, the Nakdong River estuary was divided into seven zones. Aerial photography using drones was conducted to find seagrass areas, GPS tracking was carried out on foot in the intertidal zone and by boat and SCUBA diving in the subtidal zone. To analyze the seagrass status, we measured the morphological characteristics, shoot density, and biomass of representative seagrass species in each zone. Four seagrass species were found in this area: Zostera japonica, Z. marina, Ruppia maritima, and Phyllospadix japonicus. The distribution areas of each species was 338.2 ha, 92.9 ha, 0.9 ha, and 1.4 ha, respectively, with a total area of 432.5 ha. Z. japonica was widely distributed in most of the tidal flats and mudflats of the Nakdong River estuary, while Z. marina was restricted to Nulcha-do, Jinu-do, and Dadae-dong. R. maritima occurred within the habitat of Z. japonica in Eulsukdo and Myeongji mudflats, and P. japonicus inhabited rocky areas in Dadae-dong. The shoot density of each species was 4,575.8±338.3 shoots m^-2, 244.8±12.0 shoots m^-2, 11,302.1±290.0 shoots m^-2, and 2862.5±153.5 shoots m^-2, respectively. The biomass of each species was 239.7±18.5 gDW m^-2, 362.3±20.5 gDW m^-2, 33.3±1.2 gDW m^-2, and 1,290.0±37.0 gDW m^-2, respectively. The results of this study revealed that Z. japonica was dominant in the Nakdong River estuary. In particular, Z. japonica habitats of Eulsukdo, Daema-deung, and Myeongji mudflats were identified as the largest in Korea. The Nakdong River estuary is an important site of ecological, environmental, and economic value, and will require continuous investigation and management of the native seagrasses.

• Journal of the Daesoon Academy of Sciences
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• v.46
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• pp.189-234
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• 2023

The most common and prevailing system of virtue ethics is based around the idea of personality rather than external behavior and it grew out of the Aristotelian system of virtue ethics. The purpose of this study is to find out the characteristics of the virtue ethics found within Daesoon Thought through comparison to Aristotelian virtue ethics. This can serve as a basis to establish the virtue ethics of Daesoon Thought in further studies. The systems of virtue ethics posited by the two traditions are similar in that they are both teleological as the virtues they recognize are related to human nature in the context of certain metaphysical assumption and they both exhibit the characteristic tendencies of seeking to realize the highest human good. Therefore, in the Aristotelian context, virtues can be defined as "characteristics needed for the realization of eudaimonia," and for Daesoon Thought, virtues are "characteristics needed for the realization of the Resolution of Grievances for Mutual Beneficence." The representative virtues examined in this comparative study will be the Aristotelian Golden Mean, and the the concepts of guarding against self-deception and great benevolence and great justice in Daesoon Thought. In comparison to Aristotelian virtues, these differ in three main ways. First, Aristotelian virtue is not an innate aspect of character the way it is assumed to be in Daesoon Thought wherein the original human heart bestowed by Heaven is already virtuous. Second, mental virtue in the Aristotelian context centers the mind upon reason whereas in Daesoon Thought, the heart-mind exhibits both reason and emotional concern for others. Third, eudaimonia is a concept limited to humans and their societies whereas the Resolution of Grievances for Mutual Beneficence is a good that includes all beings including divine beings, animals, plants, and Heaven and Earth. Despite the differences, both require practical reason, continuous education, and effort to succeed in the cultivation of virtues and the proper implementation of virtuous living.

• Journal of Nutrition and Health
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• v.56 no.5
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• pp.496-509
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• 2023

Purpose: This study aimed to identify the general characteristics, chronic diseases, health behavior, mental health, and nutritional status of young-old women based on their vitality. Methods: This study used data from the 2019 and 2021 Korea National Health and Nutrition Examination Survey (KNHANES). The subjects were 1,113 young-old women aged 65 to 74 years old. The health-related quality of life concept with an 8-item questionnaire was used to measure the quality of life. Subjects were categorized into 4 groups (always, often, sometimes, never) based on their vitality. General characteristics, chronic diseases, health behavior, dietary behavior, food intake, and nutrient intake were compared among the groups. Results: Age, education level, household income, employment, fruit intake, dietary supplements, abundance of food, and nutrition labeling recognition were associated with the vitality of the subjects. Young-old women with arthritis, diabetes, and osteoporosis displayed lower vitality. Moreover, subjective health status, exercise, activity restrictions, and average daily sitting hours were related to vitality, while no significant difference was found in vitality between smoking and drinking. In terms of mental health factors, higher vitality was associated with 6-8 hours of sleep, lower stress levels, and reduced depression. The high-vitality group exhibited a higher intake of potatoes, starch, mushrooms, fruits, meat, milk, animal oils, and beverages than the low-vitality group. Additionally, the group with higher levels of vitality showed a higher intake of protein, fat, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, n-6 fatty acids, dietary fiber, sugars, phosphorous, potassium, magnesium, iron, zinc, and riboflavin. Conclusion: This study suggests that the vitality of young-old women is related to socioeconomic factors, health behavior, mental health, and food intake. To maintain a vibrant lifestyle in elderly women, it is necessary to have social and economic stability, prevent arthritis, diabetes, and osteoporosis, exercise regularly, get sufficient sleep, maintain mental health, and have a balanced diet.

• Journal of Nutrition and Health
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• v.56 no.5
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• pp.537-553
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• 2023

Purpose: The purpose of this study was to evaluate the nutritional quality of complementary baby food products sold in Korea according to the baby food stages and food composition. Methods: A total of 1,587 complementary food products sold online and offline between March and December 2021 were investigated. They ranged from liquid meals to solid rice for babies aged 5 to 36 months. Results: The number of intakes per packaged volume was 2.8 in Stage 1, 1.9 in Stage 2, 1.4 in Stage 3, and 1.1 in Stage 4 (p < 0.0001). The dietary variety scores (DVS) of the complementary baby food products were 3.4 in Stage 1, 5.5 in Stage 2, 7.1 in Stage 3, and 9.7 in Stage 4 (p < 0.0001) and showed a significant increase in the later stages. The Korean dietary diversity score (KDDS) significantly increased from 2.3 in Stage 1, to 2.8 in Stage 2, 3.0 in Stage 3, and 3.4 in Stage 4 (p < 0.0001). The higher the baby food stage, the higher the proportion of grains/meat/vegetable ingredients. The ratio of protein intake to Adequate Intake (AI) or Recommended Nutrition Intake (RNI) was higher in products with a KDDS of 3 points or more, or in products with 2 points or fewer in Stages 1 and 2 (p < 0.0001, respectively). The ratio of protein intake to RNI increased as the KDDS score increased in Stages 3 and 4 (p < 0.0001, respectively). For all stages of baby foods, the ratio of protein intake to AI or RNI was high in products that included the meat group (beans, nuts, meat, eggs, fish, and shellfish) (p < 0.0001, respectively). Conclusion: Continuous research and nutritional evaluation are required for establishing nutrient content standards for commercially available baby foods, considering breast milk intake.

• Journal of Nutrition and Health
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• v.56 no.5
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• pp.554-572
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• 2023

Purpose: The purpose of the study was to analyze the priorities for educational content regarding precautions to be taken to prevent safety accidents for employees in school foodservice using the Borich priority formula and the Locus for Focus model. Methods: A survey was conducted in February 2019 on 194 employees in elementary school and 122 employees in middle- and high school foodservice in the Jeonbuk area. Demographic characteristics, status of safety accidents, safety education, and their importance and performance levels were assessed using a self-administered questionnaire. The priorities for the educational content on precautions to prevent safety accidents were based on a 3-step analysis method, including the paired sample t-test, Borich priority formula, and the Locus for Focus Model. Results: The average perceived importance of the precautions to be taken against safety accidents of employees in elementary-, middle-, and high schools was higher compared to the average performance of the employees (p < 0.001). The top priority for elementary school employees was caution against falls during the cleaning of the gas hood and the trench in the kitchen. In addition, 'awareness of chemical signs' was added as one of the top priorities of middle- and high school employees. The second highest priority items were 'do stretching', 'safely adjusting workbench height', 'keeping the right attitude', 'using assistive devices when moving heavy things', and 'checking the material safety data sheet', which were the same for all elementary, middle- and high school employees. Conclusion: Thus, to improve the educational preparedness of employees in the area of safety precautions, eight safety/accident prevention items should be included in the safety education program.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.361-372
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• 2023

Organotin pesticide is used as an acaricide in agriculture and may contaminate livestock products. This study aims to develop a rapid and straightforward analytical method for detecting organotin pesticides, specifically azocyclotin, cyhexatin, and fenbutatin oxide, in various livestock products, including beef, pork, chicken, egg, and milk, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The extraction process involved the use of 1% acetic acid in a mixture of acetonitrile and ethyl acetate (1:1). This was followed by the addition of anhydrous magnesium sulfate (MgSO₄) and anhydrous sodium chloride. The extracts were subsequently purified using octadecyl (C₁₈) and primary secondary amine (PSA), after which the supernatant was evaporated. Organotin pesticide recovery ranged from 75.7 to 115.3%, with a coefficient of variation (CV) below 25.3%. The results meet the criteria range of the Codex guidelines (CODEX CAC/GL 40). The analytical method in this study will be invaluable for the analysis of organotin pesticides in livestock products.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.319-331
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• 2023

Aminoglycoside antibiotics, also known as aminoglycosides (AGs), are veterinary drugs effective against a wide range of gram-negative and gram-positive bacteria. Owing to their recent use in cultured meats, it has become essential to establish an analytical method for safety management. AGs are highly polar compounds, and ion-pair reagents (IPRs) are used to ensure component separation. Owing to the high possibility of potential mechanical problems resulting from IPR addition to the mobile phase, an analytical method in which IPRs are added directly to the vial was explored. In this study, methods for analyzing 10 AGs via liquid chromatography-tandem mass spectrometry (LC-MS/MS) with the addition of two IPRs were validated for selectivity, detection limit, quantitation limit, recovery, and precision. The detection limit was 0.0001-0.0038 mg/kg, the quantification limit was 0.004-0.011 mg/kg, and the linearity (R²) within the concentration range of 0.01-0.5 mg/kg was over 0.99. Recovery and precision (expressed as relative standard deviation) evaluated in the two matrices (beef and cell culture media) ranged from 70.7% to 120.6% and 0.2% to 24.7%, respectively. The validated AG analytical method was then applied to 15 meats prepared from chicken, beef, and pork, and 6 culture media and additives used in cultured meat. No AGs were detected in any of the 15 meats distributed in Korea; however, streptomycin and dihydrostreptomycin were detected at levels ranging from 695.85 to 1152.71 mg/kg and 6.35 to 11.11 mg/kg, respectively, in the culture media additives. The LC-MS/MS method coupled with direct addition of IPRs to the vial can provide useful basic data for AG analysis and safety evaluation of meats as well as culture media and additives for cultured meats.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.179-192
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• 2023

In this study, changes in the microbial ecosystem of the Yeongheungdo island coastal waters were investigated for five years to collect basic data. To evaluate the influence of distance from the coast on the microbial ecosystem, four sites, coastal Site (S1) and 0.75, 1.5, and 3 km away from the coast, were set up and the changes in physicochemical and biological factors were monitored. The results showed seasonal changes in water temperature, dissolved oxygen, salinity, and pH but with no significant differences between sites. For nutrients, the concentration of dissolved inorganic nitrogen increased from 6.4 μM in April-June to 16.4 μM in July-November, while that of phosphorus and silicon phosphate increased from 0.4 μM and 2.5 μM in April-June to 1.1 μM and 12.0 μM in July-November, respectively. Notably, phosphorus phosphate concentrations were lower in 2014-2015 (up to 0.2 μM) compared to 2016-2018 (up to 2.2 μM), indicating phosphorus limitation during this period. However, there were no differences in nutrients with distance from the coast, indicating that there was no effect of distance on nutrients. Phytoplankton (average 511 cells mL^-1) showed relatively high biomass (up to 3,370 cells mL^-1) in 2014-2015 when phosphorus phosphate was limited. Notably, at that time, the concentration of dissolved organic carbon was not high, with concentrations ranging from 1.1-2.3 mg L^-1. However, no significant differences in biological factors were observed between the sites. Although this study revealed that there was no disturbance of the ecosystem, further research and more basic data on the microecosystem are necessary to understand the ecosystem of the Incheon.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.4
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• pp.355-363
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• 2023

In this study, we explore the nature of clumped isotopes of H₂O molecule using quantum chemical calculations. Particularly, we estimated the relative clumping strength between diverse isotopologues, consisting of oxygen (¹⁶O, ¹⁷O, and ¹⁸O) and hydrogen (hydrogen, deuterium, and tritium) isotopes and quantify the effect of temperature on the extent of isotope clumping. The optimized equilibrium bond lengths and the bond angles of the molecules are 0.9631-0.9633 Å and 104.59-104.62°, respectively, and show a negligible variation among the isotopologues. The calculated frequencies of the modes of H₂O molecules decrease as isotope mass number increases, and show a more prominent change with varying hydrogen isotopes over those with oxygen isotopes. The equilibrium constants of isotope substitution reactions involving these isotopologues reveal a greater effect of hydrogen mass number than oxygen mass number. The calculated equilibrium constants of clumping reaction for four heavy isotopologues showed a strong correlation; particularly, the relative clumping strength of three isotopologues was 1.86 times (HT¹⁸O), 1.16 times (HT¹⁷O), and 0.703 times (HD¹⁷O) relative to HD¹⁸O, respectively. The relative clumping strength decreases with increasing temperature, and therefore, has potential for a novel paleo-temperature proxy. The current calculation results highlight the first theoretical study to establish the nature of clumped isotope fractions in H₂O including ¹⁷O and tritium. The current results help to account for diverse geochemical processes in earth's surface environments. Future efforts include the calculations of isotope fractionations among various phases of H₂O isotopologues with a full consideration of the effect of anharmonicity in molecular vibration.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.371-384
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• 2023

We investigated the occurrence of insect pests on street trees that were planted or naturally grew in a total of six urban and suburban parks (two sites in Iksan, one site in Gimje and three sites in Gwangju) in Honam region, South Korea from May to September, 2022. The six survey sites are divided into three characters, two 'nearby forest (NF)', two 'nearby river (NR)' and two 'nearby downtown (ND)' according to the created location of sites and the results on fauna of insect pests compared with street tree species for each character of survey sites. As results, we could discover 51 species of 49 genera in 27 families belonging to five insect orders from a total of 21 tree species belonging to 13 families in six survey sites. Among the insect taxa, hemipteran pests are most diverse with 22 species of 20 genera in 12 families and it is confirmed that Prunus × yedoensis Matsum. (Rosaceae) is damaged by most diverse 25 insect pests. With regard to character of survey sites, trees in 'nearby river' were affected by most diverse 34 insect pests, even though tree species were few compare to sites of 'nearby forest' and 'nearby downtown. Among the affected area of tree parts, leaf-feeding insect pests are most diverse with 22 species. From the present study, we provided a checklist of insect pests from the street trees and selected six most concerned species. Indeed, it is needed to conduct sustainable surveys and monitoring on occurrence of insect pests from street trees in urban and suburban parks because the species of planted street trees in parks can be extremely diverse with occurrence of unexpected insect pests.