• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.4
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• pp.297-306
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• 2023

Saemangeum Lake is the largest artificial lake in Korea. The continuous deterioration of lake water quality necessitates the introduction of novel water quality management strategies. Therefore, this study aims to identify the spatiotemporal water quality characteristics of Saemangeum Lake using data from the National Water Quality Measurement Network and provide basic information for water quality management. In the water quality parameters of Saemangeum Lake, water temperature and total phosphorous content were correlated, and salt, total nitrogen content, pH, and chemical oxygen demand were significantly correlated. Other parameters showed a low correlation. The spatial principal component analysis of Saemangeum Lake showed the characteristics of its four zones. The mid-to-downstream section of the river affected by freshwater inflow showed a high nutrient salt concentration, and the deep-water section of the drainage gate and the lake affected by seawater showed a high salt concentration. Two types of water qualities were observed in the intermediate water area where river water and outer sea water were mixed: waters with relatively low salt and high chemical oxygen demand, and waters with relatively low salt and high pH concentration. In the principal component analysis by time, the water quality was divided into four groups based on the observation month. Group I occurred during May and June in late spring and early summer, Group II was in early spring (March-April) and late autumn (November-December), Group III was in winter (January-February), and Group IV was in summer (July-October) during high temperatures. The water quality characteristics of Saemangeum Lake were found to be affected by the inflow of the upper Mangyeong and Dongjin rivers, and the seawater through the Garuk and Shinshi gates installed in the Saemangeum Embankment. In order to achieve the target water quality of Saemangeum Lake, it is necessary to establish water quality management measures for Saemangeum Lake along with pollution source management measures in the upper basin.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.3
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• pp.179-188
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• 2023

Purpose. The purpose of this study was to evaluate the effect of surface treatments on the shear bond strength of two types of zirconia (3-TZP and 5Y-PSZ) with resin cement. Materials and methods. Two different types of zirconia specimens with a fully sintered size of 14.0×14.0×2.0 mm³ were prepared, polished with 400, 600, and 800 grit silicon carbide paper, and buried in epoxy resin. They were classified into four groups each control, sandblasting, primer, and sandblasting & primer. Cylindrical resin adhered to the surface-treated zirconia with resin cement. It was stored in distilled water (37℃) for 24 hours, and a shear bond strength test was performed. The normality of the experimental group was confirmed with the Kolmogorov-Smirnov & Shapiro-Wilk test. The interaction and statistical difference were analyzed using a two-way ANOVA. A post-hoc analysis was performed using Dunnett T3. Results. As a result of two-way ANOVA, there was no significant difference in shear bonding strength between zirconia types (P > .05), but there was a significant correlation in the sandblasting, primer, and alumina sandblasting & primer group (P < .05). Dunnett T3 post-test showed that, regardless of the type of zirconia, shear bonding strength was sandblasting & primer > Primer > sandblasting > control group (P < .05). Conclusion. There was no difference in shear bond strength between the types of zirconia. The highest shear bond strength was shown when the mechanical and chemical treatments of the zirconia surface was performed simultaneously.

• 한국노년학
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• v.34 no.2
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• pp.259-275
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• 2014

The purpose of this study is to check if group art therapy is effective in improving self esteem and self integrity of rural elderly women. Study subjects are forty seven rural elderly women in A-city who have participated in producing specialized products in their rural area. They are divided into experimental group (EG, n=25) who wish to participate in the group art therapy program, a part of the A-city sponsored program named 'Making the Rural Elderly Happy', to improve and enhance the elderly's self esteem and self integrity, and control group (CG, n=22) with no wish to participate. However, only forty four elderly women are selected as the final study subjects for data analysis, due to those who either missed the program session more than once or died of old age during the program period. The group art therapy program was given from March 16 to May 18 of 2010, every Tuesday between 1pm through 3pm for a total of 12 sessions, with the help of two college student assistants in the region and one staff member for the city program. SPSS WIN version 12.0 is adopted to evaluate and analyze the effects of the therapy program, independent t-test for equivalence check of pretests, and frequency check for general characteristics of each group. The study results are obtained by the mean and standard deviation to grasp the changes between pretest and post-test on both groups, together with ANCOVA to evaluate effects of the therapy program with the pre-test as covariant. The results are as follows. First, self esteem of EG is significantly improved than that of CG after intervention of group art therapy. Second, self integrity is significantly higher in EG than CG after the group art therapy intervention. Therefore, it can be claimed that group art therapy is effective in improving and enhancing self esteem and self integrity of the rural elderly women.

• Korean Journal of Culture and Social Issue
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• v.18 no.1
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• pp.127-152
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• 2012

The research investigates the attitudes toward children among mothers young children and maternal grandmothers, focusing specifically on the ideal number of children, gender preference, old age security and positive and negative values of children. A total of 442 respondents, consisting of 221 young mothers (average age of 35) and 221 maternal grandmothers (average age of 63) completed a questionnaire developed by Kim, Park and Kwon (2005). The reliability of the scales ranged from Cronbach α of .78 to .91. The results are as follows. First, as for the ideal number of children, young mothers reported that they would prefer two children, while grandmothers reported that they would prefer four children. As for the ideal number of male child, young mothers reported that they would prefer that they would prefer one son, while grandmothers reported two sons. Second, as for the gender of the child, young mothers did not show a gender preference, while grandmothers stated that at least one child should be a son, especially if it is the only child. Third, grandmothers had higher expectation of old age security in their male child than young mothers but two groups did not show any difference for the female child. Fourth, as for positive values of children, young mothers were more likely to emphasize personal aspects (i.e., psychological pleasure and happiness) and family cohesiveness, while grandmothers were more likely to emphasize social aspects (i.e., continuing the family line and old age security. As for negative values of children, young mothers were more likely to emphasize personal aspects (i.e., parental role and responsibility), while grandmothers were more likely to emphasize social aspects (i.e., family conflict and relationship). Fifth, as for factors that influenced the number of children that they decided to have, young mothers were more likely to report negative values of children (i.e., financial constraints), while grandmothers were more likely to emphasize positive values of children (i.e., continuing the family line).

• Korean Journal of Culture and Social Issue
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• v.23 no.3
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• pp.409-449
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• 2017

The main purpose of this research is to investigate the qualitative nature of Korean adolescents and their parent's perception of elderly parents care. In addition, this research exams the quantitative differences between the two generations in term of their elderly parents care self-efficacy and attitude towards caring for their elderly parents. Further, an examination of the parental influence upon their children's elderly parents care self-efficacy and attitude towards caring for their elderly parents. There were 2,460 participants in this study, with 820 adolescents, and 820 fathers and 820 mothers. The results of the study were as follows: First, in terms the participants perceptions of "the most difficult aspect of caring for elderly parents", the most representative response for adolescents was financial difficulties, while for parents differences in opinions. When it came to "the best aspect of caring for elderly parents" the most representative response for adolescents was harmonious family, while for parents good for children's upbringing. When it came to "actual acts (behavior) of elderly parents care" the most representative response for adolescents was living together with their elderly parents, while for parents looking after their elderly parents. When it came to "the best method of caring for their elderly parents" the most representative response for both adolescents and parents was providing a peace-of-mind for their elderly parents, followed by the second most frequent response of adolescents living together with their elderly parents, and for parents talking with their elderly parents. When it came to "how one feels when not caring for their elderly parents" the most representative response for both groups was a feeling of indebtedness. Second, for the quantitative analyses of the differences between the two generations, the parents showed a lower level of elderly parents care self-efficacy and a higher level of negative attitude towards caring for their elderly parents, when compared to the adolescents. Third, for the parental influence upon the adolescents' elderly parents care self-efficacy and attitude towards caring for their elderly parents, the only significant influence found was the mothers' elderly parents care self-efficacy.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.779-793
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• 2023

Intensive and long-term aquaculture activities in Korea have generated considerable amounts of organic matter, deteriorating the sedimentary environment and ecosystem. The Korean government enacted the Fishery Management Act to preserve and manage the environment of fish farms. Based on this, a fisheries environment assessment has been conducted on fish cage farms since 2014, necessitating the development of a scientific and objective evaluation method suitable for the domestic environment. Therefore, a benthic health index (BHI) was developed using the relationship between benthic polychaete communities and organic matter, a major source of pollution in fish farms. In this study, the development process and calculation method of the BHI have been introduced. The BHI was calculated by classifying 225 species of polychaetes appearing in domestic coastal and aquaculture areas into four groups by linking the concentration gradient of the total organic carbon in the sediment and the distributional characteristics of each species and assigning differential weights to each group. Using BHI, the benthic fauna communities were assigned to one of the four ecological classes (Grade 1: Normal, Grade 2: Slightly polluted, Grade 3: Moderately polluted, and Grade 4: Heavily polluted). The application of the developed index in the field enabled effective evaluation of the Korean environment, being relatively more accurate and less affected by the season compared with the existing evaluation methods like the diversity index or AZTI's Marine Biotic Index developed overseas. In addition, using BHI will be useful in the environmental management of fish farms, as the environment can be graded in quantified figures.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.730-741
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• 2023

Purpose: The 2020 Dietary Reference Intakes for Koreans (KDRIs) serves as a foundation for daily nutrient and energy recommendations aiming to enhance public health and prevent chronic diseases. They act as guidelines for maintaining proper nutrition and overall health. Using KDRIs is crucial for promoting healthier lifestyles and making informed dietary choices. Thus, this study explores the influence of a nutrition education program, based on the 2020 KDRIs, on the nutrition knowledge and dietary habits of undergraduates in Gyeongsangnam-do and Gyeonggi-do. Methods: The nutrition education program, designed with diverse instructional materials, was executed across a wide range of universities. The education group (n = 75) engaged in the program for a 6-week instructional period, while the control group (n = 53) underwent the survey without participating in the education program. Nutrition Quotient (NQ) and knowledge assessments were administered to both groups immediately before and after the instructional period. Results: Within the education group, the nutrition education program positively impacted responses to NQ practice items, including knowledge of nutrition, daily intake, and portion sizes (p < 0.05). In contrast, there were no significant differences between the before and after responses of the control group for most survey items. Post-program evaluations showed significantly higher self-assessment scores and increased satisfaction levels (p < 0.05), with the satisfaction rate for the education program using the 2020 KDRIs reaching 99.2%. Conclusion: This study has demonstrated the positive impact of an effective nutrition education program. However, there is a need for the continuous development and implementation of nutrition education programs to sustain these outcomes and further enhance the nutritional education experience.

• Journal of Life Science
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• v.33 no.10
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• pp.797-807
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• 2023

To improve the functionality of mulberry, samples were fermented with Lactobacillus plantarum JCM 1149 (LP) or Pichia kudriavzevii Atz-EN-01 (PK), and their antioxidant and anti-obesity activities were compared to those of unfermented mulberry. After fermenting for 60 hr, the total polyphenol and flavonoid content of the PK-fermented mulberry (PKFM) and LP-fermented mulberry (LPFM) was 1.5-fold and 2-fold higher, respectively, while the total anthocyanin content was 1.3-fold and 1.5-fold higher in the PKFM and LPFM, respectively. DPPH radical scavenging activity was found to be 16.3% higher (86% vs. 100%) after PK fermentation and 8.1% higher (86% vs. 93%) after LP fermentation. The lipase inhibitory activity of the LPFM and PKFM was 62.9% and 52.5%, respectively. 3T3-L1 preadipocytes were treated with unfermented mulberry, LPFM, or PKFM at 200, 400, or 800 ㎍/ml and stained with oil-red-O. A slight difference in the staining was observed in samples treated with 400 ㎍/ml. However, treatment with 800 ㎍/ml significantly reduced staining compared to the control, and the LPFM exhibited relatively higher adipogenesis inhibitory activity than the PKFM. Blood triglyceride content increased by 9.5% in the high-fat diet group, but decreased by 17.1% in the control group, 37.1% in the LPFM group, and 41.6% in the PKFM group. The blood triglyceride content of the LPFM group decreased by 43.1% and 21.4% compared to the high-fat diet group and the control group, respectively, and that of the PKFM group decreased by 48.6% and 28.9% compared to the same groups. In conclusion, the results indicate that fermented mulberry has increased antioxidant activity, lipase inhibitory activity, and adipogenesis inhibition activity, and decreased blood triglyceride content compared to unfermented mulberry.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.354-360
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• 2023

The diet composition of Tanaka's snailfish, Liparis tanakae were collected by bottom trawl net in the Yellow Sea of Korea during 2022 (April, August, October, and November). The size of the specimens ranged from 3.8 to 52.2 cm in total length. L. tanakae were primary consumed caridea shrimps (Crangon hakodatei, Eualus spathulirostris, etc.) and specialist feeder mainly consumed caridea shirmps (C. hakodatei). The L. tanakae's trophic level is 3.63. Caridea shrimps were the primary prey items for all size groups (<20 cm, 20~30 cm, 30~40 cm, ≥40 cm). The proportion of E. spathulirostris has increased as the body size of L. tanakae increased, whereas the proportion of C. hakodatei decreased gradually. As the body size of L. tanakae increased the mean weight of prey per stomach (mW/ST) tended to increase significantly (One-way ANOVA, P<0.05). The caridea shrimps were the primary prey items throught all seasons. In summer, the main prey items were the C. hakodatei, however, in autumn, the proportion of C. hakodatei decreased while the proportion of E. spathulirostris increased.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.2
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• pp.69-79
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• 2009

Major and trace elements were analyzed in three core sediments to investigate geochemical characteristics of East Sea sediments and provenance changes during late Quaternary in Ulleung Basin. Comparing with Yellow and South Sea sediments, contents of major elements were generally similar while contents of trace elements were significantly different. Furthermore, within this basin, there were some variabilities in trace element compositions. In the western slope sediments (WS), Mo was enriched over 6 times as much as other sites. On the other hand, Zr, Nb, Hf and Ta were enriched in basin sediments (Basin), and Ca and Cs were enriched in southern slope sediments (SS). After excluding elements derived from biogenic, authigenic and diagenetic origins, the lithogenic elements (K, Ti, Cs, Zr, Nb, Hf and Ta) could be classified into three groups from the comparison of element/Al ratios among cores. The first group consisted of elements (K and Ti) that showed the nearly similar element/Al ratios among three cores. The second group contained Cs which showed significant difference between two slope sediments. The third group elements (Zr, Nb, Hf and Ta) showed highly enriched in basin relative to both slope areas. The depth profiles of metal/Al ratios in basin sediments provided the following interpretation for the compositions of sediment and their variation. From 10,000 yr B.P. to 7,000 yr B.P. two lithogenic components (volcanic ashes and western slope sediments) were mixed and deposited in the basin. After 7,000 yr B.P., however, southern slope sediments were mixed with volcanic ashes and deposited in basin area. This event of source change is nearly close to inflow period of the Tsushima Warm Current to Ulleung Basin. Thus, it might be suggested that element geochemistry in Ulleung basin sediment indicate the change of current system in the study area.