• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.126-149
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• 2021

The reign of King (later Emperor) Gojong of the Joseon dynasty (later the Korean Empire), which lasted from 1863 to 1907, was a period of turmoil caused by political and social instability at home and military incursions by foreign powers. It was also a period in which Joseon was proclaimed as the Korean Empire and, accordingly, the royal seals of the dynasty underwent a major change. Records show that some 135 seals were produced during the reign of Gojong. The present study of the makers and styles of the royal seals aims to reveal a wealth of information on the seals, which typically had handles in the shape of either a turtle or dragon. Among the seal makers of this era, Jeon Heung-gil was particularly highly regarded as a Golden Royal Seal Artisan (Geumbojang) because he was highly skilled at making both turtle and dragon handles. Kim Eun-seok, a master Jade Royal Seal Artisan (Okbojang), also excelled in the production of turtle and dragon handles for his jade seals. Another master Jade Royal Seal Artisan, Yi Jung-ryeo, is noteworthy because he developed a new style of jade royal seals, which eventually became the dominant style after 1890, when Kim Eun-seok was not active. Furthermore, after the 1890s, his style was also applied to the production of the gold royal seals and developed as the dominant style. Regarding the dragon handles adopted after the proclamation of the Korean Empire, both the golden and the jade royal seals were made in the same style by the same artisans in the service of the Joseon dynasty. They adopted the style of Chinese imperial seals when they began making seals with dragon handles for the Korean Empire, although the basic shapes of both handle and dragon were copied from those made during the Joseon period. As a ceremonial object symbolizing the authority and legitimacy of the royal or imperial family, the style of the royal seals was influenced mainly by changes in the political situation at home and abroad. As Gojong's reign was a period in which more royal seals were made than in the reign of any other ruler, the seals originating from his reign constitute a richer source of information about the efforts of the dynasty to preserve the tradition while effectively dealing with the changes of the new era.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.335-341
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• 2019

In order to provide basic data for uniformization of temperature distribution in heating greenhouses, heating experiments were performed in two greenhouses with a hot water heating system. By analyzing heat transfer characteristics and improving pipes layout, measures to reduce the variation of pipe surface temperature and to improve the uniformity were derived. As a result of analyzing the temperature distributions of two different greenhouses and examining the maximum deviation and uniformity, it was found that the temperature deviation of greenhouses with a large amount of hot water flow and a short heating pipe was small and the uniformity was high. And it was confirmed that the temperature deviation was reduced and the uniformity was improved when the circulating fan was operated. The correlation between the surface temperature of the heating pipe and the indoor air temperature was a positive correlation and statistically significant(p<0.01) in both greenhouses. It was confirmed that the indoor temperature distribution in a hot water heating greenhouse was influenced by the surface temperature distribution of heating pipe, and the uniformity of indoor temperature distribution could be improved by arranging the heating pipe to minimize the temperature deviation. Analysis of the heat transfer characteristics of heating pipe showed that the temperature deviation increased as the pipe length became longer and the temperature deviation became smaller as the flow rate in pipe increased. Therefore, it was considered that the temperature distribution and the uniformity of environment in a greenhouse could be improved by arranging the heating pipe to shorten the length and controlling the flow velocity in pipe. In order to control the temperature deviation of one branch pipe within $3^{\circ}C$ in the tube rail type hot water heating system most used in domestic greenhouses, when the flow velocity in the pipe is 0.2, 0.4, 0.6, 0.8, $1.0m{\cdot}s^{-1}$, the length of a heating pipe should be limited to 40, 80, 120, 160, 200m, respectively.

• Journal of Life Science
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• v.29 no.11
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• pp.1227-1234
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• 2019

Prunus mume, also known as maesil, is a popular fruit consumed in East Asia (Korea, Japan, and China). It contains high amounts of organic acids, minerals, and polyphenols and has been used as a medication for fever, vomiting, and detoxification. In this study, the anti-proliferative and apoptotic effects of solvent fractions from maesil were evaluated using sulforhodamine B (SRB) assays, morphological evaluations, Hoechst 33258 staining, and western blotting. Addition of the maesil methanol fraction (MMF) and the maesil butanol fraction (MBF) significantly and dose-dependently decreased the cell viability of HT-29 human colon cancer cells. Colony-forming assays confirmed that the MMF and MBF treatments decreased colony numbers when compared with untreated control cells. Treatment of HT-29 cells with MMF and MBF caused a distortion of the cell morphology to a shrunken cell mass. Treatment with MMF and MBF also dose-dependently increased nuclear condensation and the formation of apoptotic bodies in HT-29 cells. Treatment with MMF and MBF significantly and dosedependently increased the expression of Bax (a pro-apoptotic protein), caspase-3, and poly ADP-ribose polymerase (PARP) and decreased the expression of Bcl-2 (an anti-apoptotic protein). MMF significantly and dose-dependently inhibited cell proliferation induced by bisphenol A, an environmental hormone. Therefore, MMF may have potential use as a functional food and as a possible therapeutic agent for the prevention of colon cancer.

• Journal of Life Science
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• v.29 no.11
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• pp.1208-1217
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• 2019

Saposhnikovia has been used as a traditional medicinal herb in Asia because of the reported anti-inflammatory, anti-allergic rhinitis, pro-whitening, anti-atopy, anti-allergy, and anti-dermatopathy effects of the phytochemical compounds it contains. In this study, we investigated the antioxidant effects of a Saposhnikovia extract after fermentation by Lactobacillus plantarum BHN-LAB 33. Saposhnikovia powder was inoculated with L. plantarum BHN-LAB 33 and fermented at $37^{\circ}C$ for 72 hr. After fermentation, the total polyphenol content of the Saposhnikovia extract increased by about 14%, and the total flavonoid content increased by about 9%. The superoxide dismutase-like activities, DPPH radical scavenging, ABTS radical scavenging, reducing power activity, and tyrosinase inhibition activity also increased after fermentation by approximately 70%, 80%, 45%, 39%, and 44%, respectively. The results confirmed that fermentation of a Saposhnikovia extract by L. plantarum BHN-LAB 33 is an effective way to increase the antioxidant effects of the extract. The bioconversion process investigated in this study may have the potential to produce phytochemical-enriched natural antioxidant agents with high added value from Saposhnikovia matrices. These results can also be applied to the development of improved foods and cosmetic materials.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.411-419
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• 2019

The purpose of this study was to analyze the growth and functional differences between C. rotundus and G. littoralis according to different electrical conductivity (EC) conditions in reclaimed soil conditions. C. rotundus and G. littoralis seeds were sown in a tray and managed for seedlings stage for eight weeks. They were transplanted in the pots containing reclaimed soils sampled in the Saemangum region. The plants were grown in the reclaimed land soil for 12 weeks under the control, 1, 2, 4, and $8dS{\cdot}m^{-1}$ conditions and in horticultural soils with EC $1.0dS{\cdot}m^{-1}$. Plant height, leaf length and width of C. rotundus were the highest in EC $1dS{\cdot}m^{-1}$. Leaf, flower and tuber numbers of C. rotundus were the highest in EC $2dS{\cdot}m^{-1}$ and the lowest in EC $8dS{\cdot}m^{-1}$, and SPAD was the highest in EC 2 and $4dS{\cdot}m^{-1}$ and the lowest in EC $8dS{\cdot}m^{-1}$. The fresh weights of shoot and root of C. rotundus grown under EC $2dS{\cdot}m^{-1}$ increased and then decreased as the concentration increased. When compared plant growth between reclaimed soil and horticulture soil with EC $1dS{\cdot}m^{-1}$, the fresh weights of shoot and root, SPAD, leaf number, flower number, and tuber number were higher in horticultural soils. Although G. littoralis grown under EC $8dS{\cdot}m^{-1}$ was the lowest in all growth parameters, there were no significant differences among other EC treatments. C. rotundus had the highest p-coumaric acid content in EC $1dS{\cdot}m^{-1}$. And the catechin content in shoot of G. littoralis was the highest in the control, and root of Glehnia littoralis had the highest benzoic acid contents in EC $1dS{\cdot}m^{-1}$. If the soil EC is well managed within $4.0dS{\cdot}m^{-1}$, two plants would be cultivated in reclaimed land.

• Journal of Life Science
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• v.30 no.12
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• pp.1092-1100
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• 2020

The six-transmembrane epithelial antigen of prostate 4 (Steap4) is a metalloreductase that plays a role in intracellular iron and cupper homeostasis, inflammatory response, and glucose and lipid metabolism. Previously, Steap4 has been reported to stimulate adipocyte differentiation; however, the underlying mechanisms of this action remain unexplored. In the present study, we investigated the molecular mechanisms involved in Steap4-induced adipocyte differentiation using 3T3-L1 cells, immortalized brown adipocyte (iBA) cells, and mouse embryonic fibroblast C3H10T1/2 cells. The knockdown of Steap4 using adenovirus-containing shRNA attenuated mitotic clonal expansion (MCE), as evidenced by the impaired proliferation of 3T3-L1 cells, iBA cells, and C3H10T1/2 cells within 48 hr after adding the differentiation medium. Steap4 knockdown downregulated G1/S phase transition-related cell cycle regulators (including cyclin A and cyclin D) and upregulated cell cycle inhibitors (including p21 and p27). Furthermore, Steap4 knockdown inhibited the phosphorylation of p38 mitogen-activated protein kinase, extracellular signal-regulated kinase, and Akt. Moreover, Steap4 knockdown repressed the expression of early adipogenic activators, such as CCAAT-enhancer-binding protein β (C/EBPβ) and Kruppel-like factor family factor 4 (KLF4). On the other hand, Steap4 knockdown stimulated the expression of adipogenic inhibitors, including KLF2, KLF3, and GATA2. The overexpression of Steap4 using an adenovirus removed the repressive histone marks H3K9me2 and H3K9me3 on the promoter of C/EBPβ. These results indicate that Stepa4 stimulates adipocyte differentiation through the induction of MCE and the modulation of early adipogenic transcription factors, including C/EBPβ, during the early phase of adipocyte differentiation.

• Pediatric Infection and Vaccine
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• v.27 no.3
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• pp.158-170
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• 2020

Purpose: We evaluated the incidence and characteristics of Clostridioides difficile infection (CDI) in Korean children. Methods: Medical records of patients aged 2-18 years and diagnosed with CDI at a tertiary hospital between 2009 and 2018 were analyzed. The patients were classified into three CDI groups: community-acquired (CA), community onset-health care facility-associated (CO-HCFA), and healthcare facility onset (HO). Results: The incidence of CDI increased from 1.00 to 10.01 cases per 10,000 admissions from 2009 to 2018 (P<0.001). As compared to the CA group, the HO group had a higher frequency of operation and malignancy as predisposing factors (40.4% vs. 0.0%, P=0.001; and 27.7% vs. 0.0%, P=0.027, respectively), frequency and number of previous antibiotic use (97.9% vs. 31.3%, P<0.001; and 2 vs. 0, P<0.001, respectively), and median postdiagnosis hospital stay (13 vs. 5 days, P=0.008). The CO-HCFA group had a lower median age and higher frequency of malignancy than the CA group (5 vs. 13 years, P=0.012; and 30.8% vs. 0.0%, P=0.030, respectively). As compared to the HO group, the CA group had a higher frequency of abdominal pain and hematochezia (56.3% vs. 10.6%, P=0.001; and 50.0% vs. 10.6%, P=0.002, respectively), inflammatory bowel disease (68.8% vs. 2.1%, P=0.001), and intravenous metronidazole treatment (37.5% vs. 2.1%, P=0.001). Conclusions: With the increasing incidence of pediatric CDI, awareness regarding its epidemiology and clinical characteristics is important to manage nosocomial infections.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.4
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• pp.258-267
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• 2020

The agrivoltaic can produce electricity and grow crops on fields at the same time. It is necessary to analyze the cultivation environment and evaluate the crop productivity under agrivoltaic because the shading point changes according to structure of agrivoltaic and sun's position. Two types of "fixing" and "tracing" agrivoltaic were installed, and a rice cultivation experiment was conducted in the fields under each agrivoltaic and without shading (control). "Hyunpoombyeo" was transplanted on June 7, 2019, and grown with fertilization of 9.0-4.5-5.7 kg/10a (N-P-K). Fifteen weather stations were installed under each agrivoltaic to measure solar radiation and temperature, and yield and yield-related elements were investigated by points. The accumulated solar radiation during the rice growing season in fixing was no much difference between points, and that in tracing was much difference between points. However, the average solar radiations of two agrivoltaics were similar. The mean temperature, yield, and yield-related elements showed a significant difference for the shading rate, and decreased with increasing the shading rate except ripening grain rate and 1000 grain weight of fixing agrivoltaic. In the relationship between shading rate and yield, fixing and tracing were fitted to a logistic equation and a simple linear equation, respectively, and showed a high correlation (tracing: R2 = 0.62, fixing: R2 = 0.73). The shading rate variation by point for two types was large despite similar yield variation. Thus, it needs to be more closely examined the relationship of the shading rate for a specific period rather than the shading rate during the whole growing season.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.382-389
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• 2020

Soil properties in opencast mines are a key factor in reclamation (revegetation) of mining areas. In this study we determined the soil physical and chemical properties of kaolinite tailings, reclaimed areas, and adjacent natural red pine (Pinus densiflora S. et Z.) forests in kaolinite opencast mines in Sancheong-gun, Gyeongsangnam-do. Six sites were chosen for collection of soil samples to determine soil physical and chemical properties at a soil depth of 10 cm. Soil bulk density was significantly higher (P < 0.05) in the kaolinite tailings (1.51 g·cm-3) than in the reclaimed areas (1.19 g·cm-3) and red pine forests (0.93 g·cm-3), whereas air phase in the kaolinite tailings (14.2%) was significantly lower than in the red pine forests (32.6%). Clay content in the red pine forests was significantly higher than in the reclaimed areas (18.7%) or kaolinite tailings (14.8%), whereas soil structural stability index was significantly lower in the reclaimed areas (1.61%) and kaolinite tailings (0.87%) than in the red pine forests (7.75%). Soil pH was significantly higher in the kaolinite tailings (pH 6.68) and reclaimed areas (pH 6.27) than in the red pine forests (pH 5.31). Soil organic carbon and total nitrogen were significantly higher in the red pine forests (C: 36.03 mg·g-1; N: 2.08 mg·g-1) than in the reclaimed areas (C: 5.00 mg·g-1; N: 0.31 mg·g-1) than in the kaolinite tailings (C: 2.12 mg·g-1; N: 0.07 mg g-1). The amount of available phosphorus was not significantly different among the three treatments. The concentration of exchangeable potassium was significantly lower in the kaolinite tailings (0.08 cmolc·kg-1) than in the reclaimed areas (0.21 cmolc·kg-1) and red pine forests (0.30 cmolc·kg-1). These results indicate that, because of high soil bulk density and low soil organic carbon, total nitrogen, available phosphorus, and exchangeable potassium in kaolinite tailings and reclaimed mining areas, soil nutrient management is needed in order to reclaim the vegetation in these type of areas.

• Journal of Nutrition and Health
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• v.53 no.6
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• pp.629-647
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• 2020

Purpose: This study was undertaken to develop a nutrition quotient for elementary school children (NQ-C) for evaluating the overall dietary quality and eating behaviors. Methods: The NQ-C was developed by implementing 3 stages: item generation, item reduction, and validation. Candidate food behavior checklist (FBC) items of the NQ-C were derived from systematic literature reviews, expert in-depth interviews, statistical analyses of the fifth Korean National Health and Nutrition Examination Survey data, and national nutrition policies and recommendations. For the pilot survey, 260 elementary school students (128 second graders and 132 fifth graders) completed self-administered questionnaires as well as 24-hour dietary intakes, with the help of their parents and survey team staff, if required. Based on the pilot survey results, expert reviews, and priorities of national nutrition policy and recommendations, checklist items were reduced from 41 to 24. A total of 20 items for NQ-C were finally selected from results generated from 1,144 nationwide samples surveyed. Construct validity of the NQ-C was assessed using the confirmatory factor analysis, LInear Structural RELations. Results: Analyses of the exploratory factors of NQ-C identified that 5 dimensions of diet (balance, diversity, moderation, practice and environment) accounted for 46.2% of the total variance. Standardized path coefficients were used as weights of the items. The NQ-C and 5-factor scores of the subjects were calculated using the obtained weights of the FBC items. Conclusion: Our data indicates that NQ-C is a useful and suitable instrument for assessing nutrition adequacy, dietary quality, and eating behaviors of Korean elementary school children.