• Journal of the Korea Organic Resources Recycling Association
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• v.32 no.1
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• pp.5-11
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• 2024

Objective of this study was to evaluate the effect of organic fertilizer application on yield, soil chemical properties and soil organic carbon (SOC) in Korean cabbage cultural field. The experimental treatments consisted of none fertilizer (NF), NPK (inorganic fertilizer, N-P₂O₅-K₂O : 320-78-198 kg ha^-1), Organic fertilizer (OF 50, 100, 150% on application rate of standard 110 kg ha^-1 as N, topdressing: 210 kg ha^-1 as inorganic fertilizer). In experimental results, the growth characteristics and yields were not significantly different among the treatments. There was no significant difference in soil pH, available phosphate, ammonium nitrogen and exchangeable potassium, while organic matter, electrical conductivity and nitrate nitrogen were increased when organic fertilizer application. Also, SOC was increased with the application of organic fertilizers. These results showed that pre-application of organic fertilizer might be effective in a carbon storage in the field soil cultivating Korean cabbage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.44 no.2
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• pp.64-70
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• 2024

The experiment was conducted to determine the changes in seed productivity of Italian ryegrass (Lolium multiflorum Lam.) according to nitrogen fertilization levels in the southern region of Korea. Italian ryegrass (IRG) variety 'Green Call' was sown in the fall of 2021 in Jinju, Gyeongsangnam-do. The experiment consisted of three nitrogen fertilizer levels (100, 120, and 140 N kg/ha) with three replications using a randomized complete block design. Harvesting was done approximately 30 days after heading on May 18th. There was no difference in heading date among treatments, which occurred on April 18th. The longest IRG was observed in the 140 N kg/ha treatment, but there was no significant difference. No significant differences were observed in lodging, disease resistance, and cold tolerance among treatments, but lodging was severe in all treatments. The length of the spike averaged 44.95 cm, with no difference among treatments, and the number of seeds per spike was highest in the 120 N kg/ha treatment. Seed yield increased with increasing nitrogen fertilizer levels, averaging 3,707 kg/ha (as-fed basis). DM content of seed and straw averaged 76.95% and 62.19%, respectively, with no significant differences among treatments. The remaining straw after harvesting averaged 6,525 kg/ha on a dry matter basis, with the highest value observed in the 140 N kg/ha treatment. Overall, considering the results, the optimal nitrogen fertilizer application rate for seed production of Italian ryegrass in the southern region when sown in autumn was found to be 120 N kg/ha.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.2
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• pp.161-202
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• 2024

Backgrounds/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions: The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

• Korean Journal of Environment and Ecology
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• v.38 no.3
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• pp.277-292
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• 2024

In order to manage large-scale forest fires concentrated in Gangwon-do and Gyeongsangbuk-do with severe topographical heterogeneity, a decision-making process through efficient and rapid damage assessment using satellite images is essential. Accordingly, this study targets a large-scale forest fire that ignited in Gangneung and the Donghae, Gangwon-do on March 5, 2022, and was extinguished around 19:00 on March 8, to estimate the fire severity using dNBR and derive environmental factors that affect the grade. As environmental factors, we quantified the regular vegetation index representing vegetation or fuel type, the forest index that classifies tree species, the regular moisture index representing moisture content, and DEM in relation to topography, and then analyzed the correlation with the fire severity. In terms of fire severity, the widest range was 'Unbured' at 52.4%, followed by low severity at 42.9%, medium-low severity at 4.3%, and medium-high severity at 0.4%. Environmental factors showed a negative correlation with dNDVI and dNDWI, and a positive correlation with slope. Regarding vegetation, the differences between coniferous, broad-leaved, and other groups in dNDVI, dNIWI, and slope, which were analyzed to affect the fire severity, were analyzed to be significant with p-value < 2.2e-16. In particular, the difference between coniferous and broad-leaved forests was clear, and it was confirmed that coniferous forest suffered more damage than broad-leaved forest due to the higher fire severity in the Gangwon-do region, including Pinus densiflora, which are dominant species, as well as P. koraiensis, P. rigida and P. thunbergii.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.637-656
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• 2023

River estuaries are dynamic and productive ecosystems with high regional biodiversity. Environmental DNA (eDNA) has become a useful approach to assessing biodiversity in aquatic ecosystems. This study was conducted to investigate fish community characteristics and species diversity in two river estuary ecosystems, the Taehwa River and Changwon Stream. We further compared conventional and eDNA metabarcoding analyses of the fish communities. The conventional survey was performed in May, July, and October 2022, while the eDNA analysis was conducted only in May. We observed various fish species with different life histories, including carp, goby, and marine fish. We also found that migratory fish, such as dace Tribolodon hakonensis, sweetfish Plecoglossus altivelis, and eel Auguilla japonica, occurred in the Taehwa River, suggesting high river connectivity. Marine fish species were predominant in the Changwon Stream, as this river is located close to the sea. The diversity indices showed that the Taehwa River generally had higher species richness, evenness, and diversity values than the Changwon Stream. A total of 9-19 species were detected in the conventional survey for the three sites, whereas 11-18 species were found from eDNA analysis. The findings indicate that the sensitivity of eDNA was similar to or higher than that of the conventional method. Our study findings suggest the efficiency and efficacy of eDNA-based fish community monitoring, although with some shortcomings in applying the genetic marker to Korean fish, including no clear-cut distinction for Korean endemic species and/or genetically closely related species groups.

• Korean Journal of Plant Resources
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• v.37 no.4
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• pp.411-422
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• 2024

Naked oat is particularly vulnerable to cold weather among cereal crops, and frequent lodging due to their long culm length. Also it is difficult to cultivate in double cropping system with rice because of late maturity in Korea. In this study, we charaterized 71 naked oat germplasms including two control varieties with agronomic traits, to select superior resources and use them for the improvement of exsiting varieties. The maturity date was May 26th for 'Joyang' and June 1st for 'Daeyang', and there were 5 resources including IT302003, which was earlier than Daeyang. In the case of culm length, the distribution ranged from 62 to 124 cm, and there were 13 resources, including IT209241, that were shorter than 'Joyang' (84 cm) and 'Daeyang' (83 cm). In correlation analysis of agronomic traits, the highest positive correlation (r=0.89) was observed between days to heading and days to maturity. In addition, culm length and spike length (r=0.72) and days to heading (r=0.50) showed a positive correlation. However, Barley yellow dwarf virus(BYDV) and grain yield (r=-0.30), lodging tolerance and liter weight (r=-0.37) showed a negative correlation. Cluster analysis, resources with similar traits such as liter weight, husk ratio, days to heading, and days to maturing were subclassified. Through this analysis, 6 resources, including IT302002 (X345-1-B4-20-1), which had short culm length, early maturity, and cold tolerance compared to 'Joyang' and 'Daeyang', were selected. Among the selected excellent resources, the avenanthramide content of the four resources was IT302002 (325.18 ㎍/g), K000010 (557.3㎍/g), K253299 (447.33 ㎍/g), and K253301 (440.49 ㎍/g), respectively, which was higher than 'Daeyang' (301.97 ㎍/g). These excellent resources will be used as breeding materials for the development of new varieties in the future.

• Korean Circulation Journal
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• v.52 no.9
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• pp.699-711
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• 2022

Background and Objectives: We investigated whether extra-pulmonary vein (PV) ablation targeting a high maximal slope of the action potential duration restitution curve (Smax) improves the rhythm outcome of persistent atrial fibrillation (PeAF) ablation. Methods: In this open-label, multi-center, randomized, and controlled trial, 178 PeAF patients were randomized with 1:1 ratio to computational modeling-guided virtual Smax ablation (V-Smax) or empirical ablation (E-ABL) groups. Smax maps were generated by computational modeling based on atrial substrate maps acquired during clinical procedures in sinus rhythm. Smax maps were generated during the clinical PV isolation (PVI). The V-Smax group underwent an additional extra-PV ablation after PVI targeting the virtual high Smax sites. Results: After a mean follow-up period of 12.3±5.2 months, the clinical recurrence rates (25.6% vs. 23.9% in the V-Smax and the E-ABL group, p=0.880) or recurrence appearing as atrial tachycardia (11.1% vs. 5.7%, p=0.169) did not differ between the 2 groups. The post-ablation cardioversion rate was higher in the V-Smax group than E-ABL group (14.4% vs. 5.7%, p=0.027). Among antiarrhythmic drug-free patients (n=129), the AF freedom rate was 78.7% in the V-Smax group and 80.9% in the E-ABL group (p=0.776). The total procedure time was longer in the V-Smax group (p=0.008), but no significant difference was found in the major complication rates (p=0.497) between the groups. Conclusions: Unlike a dominant frequency ablation, the computational modeling-guided V-Smax ablation did not improve the rhythm outcome of the PeAF ablation and had a longer procedure time.

• Journal of Korean Home Economics Education Association
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• v.36 no.2
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• pp.65-88
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• 2024

This study aims to explore the knowledge structure of the field of home economics education. To achieve this, the knowledge network of the field of home economics education was analyzed using social network analysis on 758 articles published between 2004 and 2023, focusing on those in the Journal of Home Economics Education Research. The main findings of the study are as follows: First, the knowledge network exhibited characteristics of a small-world network. Papers on children, family, and career maturity significantly influenced the knowledge structure. Second, the knowledge structure is centered around the home economics subject and curriculum and is organized into four groups. A temporal analysis revealed that the influence of core keywords such as perception, content, unit, home economics teachers, practice, behavior, and influence has decreased, while the influence of curriculum, textbook, and development has shown a trend of increasing. Third, the sub-knowledge structures were identified as seven categories. The study found that the influence of 'perception and demand for home economics education' is decreasing, whereas the influence of 'home economics curriculum and textbooks' and 'application of home economics teaching and learning process' is increasing. Additionally, 'adolescent self-esteem and family relationships' and 'home economics curriculum and textbooks' were found to be the most influential in the knowledge structure of home economics education. This research is significant as it demonstrates the temporal changes in the core keywords and sub-structures of the knowledge structure within the field, thereby providing a foundation for understanding and expanding the research knowledge structure in the field of home economics education.

• Journal of the Korean Society of Radiology
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• v.18 no.4
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• pp.345-353
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• 2024

The purpose of this study was to suggest an appropriate collimation size and central X-ray incidence point by analyzing the correlation between the collimation size used in lumbar lateral examination and factors affecting the collimation size. the lumbar lateral examination results of 148 patients suitable for the purpose of this study were analyzed. The measurement method was to set the total horizontal width shown in the image to the size of the irradiation field(collimation) used during the examination. The distance connected vertically from the end of the dorsal field to the apophyseal joint of the third lumbar vertebra(AJD), the distance from the dorsal end of the image field to the center of the body of the third lumbar vertebra(BD), and the distance from the end of the dorsal field of the image to the center of the pedicle of the third lumbar vertebra(PD). The distance was measured. For comparative analysis of the mean values of dependent variables according to gender, age, height, weight, and body mass index, the mean values were compared using the independent samples t test and one-way ANOVA. For post hoc analysis, duncan was used. The correlation between independent and dependent variables was analyzed using Pearson correlation analysis. In this study, statistical significance was set at a p value of 0.05 or lower. The average value of the collimation size during the lumbar spine lateral examination was 252.45 mm, AJD was 102.11 mm, BD was 141.17 mm, and PD was 119.73 mm. The mean values of collimation size, AJD, BD, and PD were larger in men than in women, but statistical significance for the difference in mean values by gender was found only in BD (p<0.05). There was a slight difference in the mean value of each group according to age, but there was no statistical significance (p>0.05). The collimation size and mean values of AJD, BD, and PD according to height, weight, and body mass index differed depending on the independent variables, and the differences were all statistically significant (p<0.05). As a result of the correlation analysis, field size and AJD, BD, and PD showed no correlation with gender and age, a weak positive correlation with height, and a medium positive correlation with weight and body mass index. The results of this study showed that CS was correlated with height, weight, and BMI during lumbar lateral examination. If the entrance point of the central X-ray is moved to the appophyseal joint by considering weight and BMI when adjusting the collimation size in clinical practice, it is expected that the collimation size can be reduced bu about 5%.

• Journal of Nutrition and Health
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• v.57 no.4
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• pp.418-434
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• 2024

Purpose: The nutritional status of folate in Korean adults was evaluated using the newly established folate database (DB) and data from the 7th Korea National Health and Nutrition Examination Survey. Methods: This study analyzed the folate intake of 15,054 people (6,278 men and 8,776 women) and the relationship with serum folate concentration of 5,260 people (2,272 men and 2,988 women). Results: The average daily folate intake among Korean adults was lowest in the 19 to 29-year age group and highest in those in their 50s. Folate intake was higher in groups with higher education and household income, non-smokers, participants in aerobic physical activity, and dietary supplement users regardless of sex. Among men, office workers consumed more folate than physical workers. Vegetables and grains were the first and second most contributing food groups to folate intake. The serum folate levels were higher in women than men and lowest in the 19-29 year age group for both sexes. After adjusting for energy intake, age, income, smoking, physical activity, and dietary supplement intake, serum folate concentration increased significantly as intake increased (p < 0.001). The explanatory power (R²) of folate intake on the blood folate concentration was 0.183 and 0.141 in men and women, respectively. Conclusion: The proportion of participants consuming less than the estimated average requirement was 48.1% and 65.3% in men and women, respectively. In particular, the folate intake and serum levels of young men aged 19-29 years were the lowest. Therefore, it is necessary to improve their folate nutritional status through a balanced diet. In addition, the newly established folate DB may be useful for evaluating the folate nutritional status of Koreans.