• The Journal of Engineering Geology
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• v.34 no.2
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• pp.229-248
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• 2024

This investigated the hydrogeochemical and isotopic characteristics of geothermal waters, groundwaters, and surface waters in Dongrae-gu, Busan, South Korea, in order to determine the origins of the salinity components in the geothermal waters, and their formation mechanisms and heat sources The geothermal waters are Na-Cl-type, distinct from surrounding groundwaters (Na-HCO₃^- and, Ca-HCO₃^- (SO₄, Cl)-type) and surface waters (Ca-HCO₃(SO₄, Cl)-type). This indicates the geothermal waters formed at depth as compared with the groundwaters. δ¹⁸O and δD values of the geothermal waters are relatively depleted as compared with the groundwaters, due to altitude effects and deep circulation of the geothermal waters. Helium and neon isotope ratios (³ He/⁴He and, ⁴He/²⁰Ne) of the geothermal waters plot on a single mixing line between mantle (³He = 3.76~4.01%) and crust (⁴He = 95.99~96.24 %), indirectly suggesting that the heat source is due to the decay of radioactive elements in rocks. The geothermal reservoir temperatures were calculated using the silica-enthalpy and Giggenbach models, yielding values of 82~130℃, and the depth of the geothermal reservoir is estimated to be 1.7~2.9 km below the surface. The correlation between Cl/Na and Cl/HCO₃ for the Dongrae geothermal waters requires the input of salty water. The supply of saline composition is interpreted due to the dissolution of residual paleo-seawater.

• Journal of Food Hygiene and Safety
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• v.39 no.1
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• pp.44-53
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• 2024

Global interest in natural functional materials to strengthen human immunity is increasing due to the increase in immune-related diseases associated with COVID-19 and the aging population. In this study, we determined the potential therapeutic effect of Eleutherococcus senticosus stems on immune enhancement according to the cultivation region. The contents of eleutheroside B and E, which are chemical components of E. senticosus stems, were analyzed. We showed that the eleutheroside B content of E. senticosus stems in different cultivation regions ranged from 2.96±0.11 to 6.24±0.05 mg/g and from 1.11±0.05 to 2.11±0.03 mg/g in 70% ethanol and hot water extracts, respectively. The eleutheroside E content ranged from 4.93±0.20 to 10.79±0.03 mg/g and 1.75±0.14 to 3.64±0.05 mg/g in 70% ethanol and hot water extracts, respectively. In addition, the immunomodulatory effect of E. senticosus stems was evaluated using RAW 264.7 macrophages. The 70% ethanol extract of E. senticosus stems showed no cytotoxicity up to 200 ㎍/mL, and the hot water extract showed no cytotoxicity up to 500 ㎍/mL. Additionally, the E. senticosus stem extract significantly increased the production of nitric oxide and cytokines (TNF-α, IL-6, and IL-1β) compared to their production in the control group. These results suggest that E. senticosus stem extracts are a potential functional food material and ingredient to enhance the immune response.

• Journal of the Microelectronics and Packaging Society
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• v.31 no.1
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• pp.16-22
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• 2024

Along with the high interest in electric vehicles and new renewable energy, there is a growing demand to apply lithium-ion batteries in the construction equipment industry. The capacity of heavy construction equipment that performs various tasks at construction sites is rapidly decreasing. Therefore, it is essential to accurately predict the state of batteries such as SOC (State of Charge) and SOH (State of Health). In this paper, the errors between actual electrochemical measurement data and estimated data were compared using the Dual Extended Kalman Filter (DEKF) algorithm that can estimate SOC and SOH at the same time. The prediction of battery charge state was analyzed by measuring OCV at SOC 5% intervals under 0.2C-rate conditions after the battery cell was fully charged, and the degradation state of the battery was predicted after 50 cycles of aging tests under various C-rate (0.2, 0.3, 0.5, 1.0, 1.5C rate) conditions. It was confirmed that the SOC and SOH estimation errors using DEKF tended to increase as the C-rate increased. It was confirmed that the SOC estimation using DEKF showed less than 6% at 0.2, 0.5, and 1C-rate. In addition, it was confirmed that the SOH estimation results showed good performance within the maximum error of 1.0% and 1.3% at 0.2 and 0.3C-rate, respectively. Also, it was confirmed that the estimation error also increased from 1.5% to 2% as the C-rate increased from 0.5 to 1.5C-rate. However, this result shows that all SOH estimation results using DEKF were excellent within about 2%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.438-444
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• 2023

Italian ryegrass (Lolium multiflorum Lam.; IRG) sowing season is delayed due to the autumn rainy season. Therefore, to address this problem, transplanting date and plant density were investigated. Transplant times investigated were October 20th, October 30th, and November 10th and planting densities were 50, 70, and 80 hills per 3.3 m². The plant height, leaf area index, and plant coverage rate were high in the following order: October 20th, October 30th, and November 10th. There was no significant difference among planting densities. In addition, the number of tillers and dry weight before and after wintering were high on October 20th. In terms of yield components, the number of tillers, dry weight, and seed yield per unit area were higher with the transplanting date of October 20th than with transplanting on November 10th. There was no difference in seed yield between the planting densities of 80 and 70 hills per 3.3 m². However, seed yield was low at 50 hills per 3.3 m². In conclusion, the transplanting time for stable seed production is late October, and optimal plant density is 70 and 80 hills per 3.3 m². A stable interplanting number before wintering will contribute to the seed yield.

• Journal of the Korean Society of Radiology
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• v.83 no.1
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• pp.127-137
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• 2022

Purpose To assess the prevalence of incidentally detected lumbar spondylolysis in children. Materials and Methods We retrospectively reviewed the data of 809 patients under the age of 11 years (mean age, 7.0 ± 2.7 years; boys:girls = 479:330) who underwent abdominal and pelvic CT between March 2014 and December 2018. We recorded the presence, level, and laterality (unilateral or bilateral) of spondylolysis. Patients were divided into two groups based on the presence of spondylolysis: the spondylolysis (SP) and non-SP groups. Results In total, 21 cases of spondylolysis were detected in 20 patients (20/809, 2.5%). The mean age of the SP group was higher than that of the non-SP group (7.8 ± 1.8 vs. 6.9 ± 2.7 years, p > 0.05). The prevalence of spondylolysis in boys was higher than that in girls (15/479 [3.1%] vs. 5/330 [1.5%], p > 0.05). The prevalence of spondylolysis in school-age children (6-10 year olds) was higher than that in preschool-age children (0-5 year olds) (17/538 [3.2%] vs. 3/271 [1.1%], p > 0.05). L5 was the most common level of spondylolysis (76.2%); one 8-year-old boy had two-level spondylolysis. One case of isthmic spondylolisthesis was detected in a 10-year-old boy (1/809, 0.1%). There were 11 unilateral spondylolysis cases (11/21, 52.4%). Conclusion In our study, the prevalence of spondylolysis in children under the age of 11 was 2.5%. The prevalence was higher in boys than in girls and in school-age than in preschool-age children, despite the lack of any statistically significant differences.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.281-287
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• 2024

This study investigated the total sugar and low-calorie sweetener content in 72 alcoholic beverages. The samples included 10 takjus, 6 yakjus, 5 cheongjus, 5 beers, 12 fruit wines, 5 sojus, 5 general distilled alcoholic beverages, 9 liqueurs, and 15 other alcoholic beverages. Sugar and allulose content were analyzed using HPLC-RI, and the content of five sweeteners was analyzed using HPLC-UV and LC-MSMS. The average sugar content in the alcoholic beverages was 4.13±5.16 g/100 g. When categorized by type, the sugar content ranged from 0.00 to 8.92 g/100 g, 0.00 to 30.55 g/100 g, and 0.14 to 17.02 g/100 g in fermented (takju, yakju, cheongju, beer, and fruit wine), distilled (soju, general distilled alcoholic beverages, and liqueur), and other alcoholic beverages, respectively. Sugar content was the highest in liqueur, with the average content being 12.41±9.66 g/100 g. Among low-calorie sweeteners, acesulfame potassium, sodium saccharin, aspartame, and sucralose were detected in concentrations ranging from 28.6-121.5, 42.3, 34.1-141.5, and 23.3-88.1 mg/kg, respectively. Cyclamate and allulose were not detected in any of the alcoholic beverages. Sweeteners were detected in 24 out of the 72 alcoholic beverages, and their content complied with the standards stipulated for food additives.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.221-230
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• 2024

Pesticide residues were monitored in dried red pepper and pepper powder samples purchased in Northern Gyeonggi-do and from domestic online markets. The QuEChERS method was used to prepare 88 samples. GC-MS/MS and LC-MS/MS were used to analyze 338 pesticide residues. In the study, pesticide residues were detected in 70 samples (79.5%), with residues exceeding the maximum residue limits (MRL) in 4 samples (4.5%). Pesticide levels exceeded the MRL in imported samples, with two samples of dried red pepper and two samples of pepper powder showing elevated levels. Among the 61 pesticides detected, tebuconazole, a fungicide was most frequently detected (52 times). Tricyclazole, which is used to control the main disease affecting rice, exceeding the MRL in 3 of 12 Vietnam-origin samples. Ethion exceeded the MRL in one Indian-origin sample. Both tricyclazole and ethion are banned for use in pepper products in Korea and are regulated under the positive list system (PLS). Conversely, pesticides detected in domestic samples were within the MRLs. Therefore, authorities should monitor pesticide residues in imported red pepper products.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.250-259
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• 2024

In this study, we investigated in pesticide residues and heavy metals in fermented liquor products (wine, beer, makgeolli). Targeted analysis of 400 pesticide residues in the sample was performed using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method, followed by gas chromatography-tandem mass spectrometry (MS/MS) and LC-MS/MS. The contents of heavy metals (Pb, Cd) were determined by ICP-MS using the microwave method. The mercury was measured using a mercury analyzer. From the analysis of 150 cases, 102 (68.0%) cases of fermented liquor were detected, and 35 pesticide residues (including metalaxyl, mandipropamid, azoxystrobin, and fenhexamid) were detected among the 400 pesticide residues tested. Pb, Cd, and Hg were tested in 150 samples. Lead was detected in 73 samples (48.7%), cadmium in 9 samples (6.0%), and mercury in 36 samples (24.0%). Exposure assessment was conducted to determine the safety of the detected pesticide residues and heavy metals. According to this assessment, the pesticide residues and heavy metals showed very low %ADI values (less than 1%).

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.42 no.3
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• pp.42-50
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• 2024

This study aims to develop a method for assessing the structural stability of large-old trees, which are typically evaluated primarily for their physiological health. To achieve this, finite element analysis(FEA) was applied to Zelkova serrata (Thunb.) Makino, which are significant as natural monuments, protected trees and street trees in urban areas and parks. Four representative large-old trees in Buyeo-gun, which had undergone surgical treatment, were selected for creating analytical models and being conducted FEA. The key findings are as follows: first, we made 3D models by acquiring 3D scanning and ultra sonic tomography data for analyzing FEA. We proposed methods for constructing 3D meshes and calculating self-weight and wind loads based on tree shape to interpret FEA. Second, the study confirmed that wind loads increase proportionally with the size of the tree and the shape of the canopy. Wind loads were observed irregularly in cases of unusual shapes or multiple segments of the canopy. Third, FEA's result of large-old trees with decay-induced cavities indicated that even under strong winds (70m/s) from typhoons, the likelihood of damage from trunk breakage due to self-weight was relatively low. Fourth, decay-induced cavities were found to affect internal stress distribution, leading to structural weaknesses. This highlights the need for measuring and documenting the shape of cavities during tree assessments. Accurate measurement and documentation of branching and tree form are also crucial, as complex branching and cavities increase the likelihood of structural weaknesses. The study also identified limitations in estimating self-weight, transmissivity, and projected areas of the canopy based on wind direction. To improve the accuracy of FEA, the method for enhancing precision of the 3D model and measuring the canopy and is necessary.

• Allergy, Asthma & Respiratory Disease
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• v.12 no.3
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• pp.125-133
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• 2024

Allergen immunotherapy (AIT) has been used for over a century and has been demonstrated to be effective in treating patients with various allergic diseases. AIT allergens can be administered through various routes, including subcutaneous, sublingual, intra-lymphatic, oral, or epicutaneous routes. Sublingual immunotherapy (SLIT) has recently gained clinical interest, and it is considered an alternative treatment for allergic rhinitis (AR) and asthma. This review provides an overview of the current evidence-based studies that address the use of SLIT for treating AR, including (1) mechanisms of action, (2) appropriate patient selection for SLIT, (3) the current available SLIT products in Korea, and (4) updated information on its efficacy and safety. Finally, this guideline aims to provide the clinician with practical considerations for SLIT.