• Journal of the Korean earth science society
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• v.45 no.2
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• pp.136-146
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• 2024

This paper introduces the seismic facies classification and mapping of igneous bodies found in the sedimentary sequences of the Yellow Sea shelf area of Korea. In the research area, six extrusive and three intrusive types of igneous bodies were found in the Late Cretaceous, Eocene, Early Miocene, and Quaternary sedimentary sequences of the northeastern, southwestern and southeastern sags of the Gunsan Basin. Extrusive igneous bodies include the following six facies: (1) monogenetic volcano (E.mono) showing cone-shape external geometry with height less than 200 m, which may have originated from a single monogenetic eruption; (2) complex volcano (E.comp) marked by clustered monogenetic cones with height less than 500 m; (3) stratovolcano (E.strato) referring to internally stratified lofty volcanic edifices with height greater than 1 km and diameter more than 15 km; (4) fissure volcanics (E.fissure) marked by high-amplitude and discontinuous reflectors in association with normal faults that cut the acoustic basement; (5) maar-diatreme (E.maar) referring to gentle-sloped low-profile volcanic edifices with less than 2 km-wide vent-shape zones inside; and (6) hydrothermal vents (E.vent) marked by upright pipe-shape or funnel-shape structures disturbing sedimentary sequence with diameter less than 2 km. Intrusive igneous bodies include the following three facies: (1) dike and sill (I.dike/sill) showing variable horizontal, step-wise, or saucer-shaped intrusive geometries; (2) stock (I.stock) marked by pillar- or horn-shaped bodies with a kilometer-wide intrusion diameter; and (3) batholith and laccoliths (I.batho/lac) which refer to gigantic intrusive bodies that broadly deformed the overlying sedimentary sequence.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.2
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• pp.141-157
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• 2024

This study analyzes the effect of enterepreneurial competencies on start-up performance through network activities for young entrepreneurs. Enterepreneurial competencies are composed of opportunity recognition competencies, marketing competencies, technical competencies, and creative competencies. A total of 354 questionnaires collected from young entrepreneurs residing in the country were used for empirical analysis. SPSS v28.0 and PROCESS macro v4.3 were analyzed based on the research model of a single-parameter single-mediated model. As a result of the analysis, first, it was found that among the enterepreneurial competencies, opportunity recognition competencies, marketing competencies, technical competencies, and creative competencies have a positive (+) significant effect on network activities. Among them, it was found that marketing competence has the greatest effect on network activities and technical competence has the least effect. Second, network activities were found to have a significant effect on start-up performance in a positive (+) direction. Third, among enterepreneurial competencies, opportunity recognition competence, marketing competence, technical competence, and creative competence were found to have a positive (+) effect on start-up performance. Among them, it was found that creative competence had the greatest effect and technical competence had the smallest effect. Fourth, network activities were found to mediate between enterepreneurial competencies and start-up performance. As for the relative effect size of the indirect effects of independent variables, it was found that marketing competence had the greatest effect on start-up performance and technology competence had the smallest effect. The academic implications of this study include investigating the significance and relationship of various variables, providing verification of theoretical frameworks related to entrepreneurship, identifying the main drivers of start-up success, and suggesting the importance of the network between enterepreneurial competencies and start-up performance. In addition, the practical implications of this study suggest the importance of marketing competencies for networking, and suggest differentiation of competencies. It emphasizes the strategic role of creative competence and provides guidance to policymakers for supporting start-ups on customized policies for fostering valuable start-ups.

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.95-101
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• 2024

In this study, we investigated the migration level of items specified in the Korean Standards and Specifications for Utensils, Containers, and Packages (Ministry of Food and Drug Safety Notification) for 50 utensils and hygiene products made of biodegradable resins. Our results revealed that one Polylactide (PLA) baby tableware contained 20 mg/L in consumption of potassium permanganate, exceeding the standard of 10 mg/L or less. In all other samples, formaldehyde, lead (Pb), and arsenic (As) levels could be considered very safe and remained below the standard. Moreover, we tested the PLA baby tablewares (n = 21) for migration into a food simulant (4% v/v acetic acid) upon repeated elution at 100℃ for 30 min or UV irradiation for 2 h. We detected increased formaldehyde and As amounts at the repeated 100℃ treatment for 30 min compared to those upon repeated UV irradiation. However, the migration level was markedly low under both conditions. Furthermore, the Estimated Daily Intake (EDI) calculated on an infant-to-child basis from the formaldehyde and As migration at 100℃ for 30 min in the PLA sample was at the maximum value, i.e., 6.0×10^-4 mg/kg b.w./day and 1.3×10^-1 ㎍/kg b.w./day, corresponding to 0.40% and 10.42% of the Tolerable Daily Intake (TDI, 0.15 mg/kg b.w./day) and Provisional Tolerable Weekly Intake (PTWI, 9.0 ㎍/kg b.w./week), respectively. Therefore, in this study, we confirmed that biodegradable synthetic resins are safe to use for food.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.189-203
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• 2024

This study conducted a survey two times at 20 points from April to June and from August to October 2022 to characterize the fish community and reveal the health of the Anyang stream. The survey collected 3,186 individuals belonging to 5 orders, 10 families and 34 species. The dominant species was Zacco platypus (43.4%), followed by Carassius auratus (10.1%), Cyprinus carpio (7.6%), Zacco koreanus (6.2%), Pungtungia herzi (5.2%), Oryzias sinensis (5.1%), Pseudorasbora parva (4.7%), Squalidus gracilis majimae (4.4%), Rhynchocypris oxycephalus (3.5%), Hemiculter eigenmanni (3.3%), Rhodeus ocellatus (1.4%), and Chelon haematocheilus (1.0%). Among the emerged species, 5 species (14.7%), including Rhodeus uyekii, Squalidus japonicus coreanus, and Odontobutis interrupta, were endemic to Korea, and 4 species (11.8%), including Cyprinus carpio (Israeli type), Lepomis macrochirus, Micropterus salmoides, and Poecilia reticulata, were exotic. The fish community analysis showed that the dominance was higher at the upper reaches of the Anyang stream and decreased downstream, and diversity, richness, and evenness were higher in tributary than mainstream. Stream health (fish assessment index, FAI) was generally poor, as it was rated as moderate (C) at seven sites, poor (D) at eight sites, and very poor (E) at five sites. Water quality was evaluated at eight sites, and it was rated as poor (V) at two sites, slightly poor (IV) at one site, moderate (III) at four sites, and slightly good (II) at one site, indicating that the overall water quality was poor and that the water quality had a significant impact on river health and fish habitat. Moreover, it was found that many weirs without fishways were constructed in the Anyang stream and became an obstacle to fish migration. Therefore, a systematic management plan to improve water quality and add fishways is necessary to improve the stream's health and conserve stable fish habitat.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.2
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• pp.179-192
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• 2024

In this study, six types of natural products, Prunus tomentosa (P. tomentosa), Akebia quinata (A. quinata), Prunus armeniaca (P. armeniaca), Smallanthus sonchifolius (S. sonchifolius), Citrus japonica (C. japonica), and Citrus australasica (C. australasica), were used to verify the effect of improving sleep and skin barriers by stress relief. As a result of the experiment, the production of cortisol, a stress hormone, was significantly inhibited by the P. tomentosa, C. australasica, A. quinata, and C. japonica among the six natural products. In addition, the expression of GAD67, a GABA-producing enzyme involved in sleep regulation, showed a significant increase in P. tomentosa purified water extract and C. australasica 50% ethanol extract, and the extract by each P. tomentosa solvent was found to have the highest total polyphenol content. Based on the results, the P. tomentosa extract with the highest activity was finally selected, and subsequent experiments were conducted. Among each P. tomentosa solvent extract, the DPPH radical scavenging activity was the highest in the 30% ethanol extract, and purified water extract increased GABA production and skin barrier factors filaggrin and claudin-1 expression the highest. HPLC analysis confirmed quercitrin as the main component of P. tomentosa extract, and quercitrin content by extraction solvent was high in the order of 30% ethanol > purified water > 70% ethanol > 50% ethanol. Quercitrin inhibited the production of cortisol in a concentration-dependent manner, significantly increasing GAD67 expression and GABA production, which had been reduced by cortisol. From the results of this study, it has been demonstrated that P. tomentosa can be used as a cosmetic material to help improve sleep and strengthen skin barriers by relieving stress.

• Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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• v.1
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• pp.150-173
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• 2024

The Gyeongsang region experienced an epoch-making social transformation approximately around the second to first century BCE, including the replacement of Bronze Age types of tombs (such as dolmens, stone cist tombs, and earthen tombs with flat capstones) with clusters of wooden coffin tombs and the emergence of wajil pottery (soft stoneware) and ironware. These shifts in the archaeological material evidence have been discussed in the context of the formation of the states that comprised the three Han confederacies and in relation to wooden coffin tombs built in later periods. This paper explicates the appearance of clustered wooden coffin tombs with accompanying ironware by categorizing them. In particular, it examines the emergence of wooden coffin tombs by creating the Wolseong-dong type, which differs from Tomb No. 5 in Joyang-dong and Tomb No. 1 in Daho-ri with their deep burial pits and large quantities of prestige goods and soft stoneware items. The Wolseong-dong type of tomb commonly features ironware, including flat-bladed iron axes, oblong cast iron axes, iron wire, iron chisels, and iron swords; a small slender, rectangular wooden coffin tomb with a shallow burial pit of less than sixty centimeters; and pottery of a type preceding soft stoneware, such as long-necked jars, triangular attached-rim pottery bowls and pots, and mounted vessels. There are also a few bronzeware items found in them, but no prestige goods. This study scrutinizes tombs in Tamni-ri in Uiseong, Hagu-ri in Gyeongju, and Hakjeongdong in Daegu by comparing them with the Wolseong-dong type, and it confirms that in Sinseodong in Daegu, Wolseong-dong type tombs and later Joyang-dong type tombs have separate spatial distributions within the site. This also indicates that the Wolseong-dong type is a valid categorization among wooden coffin tombs. Although the rise of the Wolseong-dong type tomb is associated with the migration of a group, I reserve judgement on whether its origins should be understood in the context of the iron culture in the southwestern region of South Korea that was sparked by King Jun's advance to the south or if they lie in the western region of North Korea. Either way, the Wolseong-dong type is thought to be the tombs of a group of people with lower hierarchical status than the occupants of the later Joyang-dong type.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.2
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• pp.147-155
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• 2024

Gallium-68-prostate-specific membrane antigen-11 (⁶⁸Ga-PSMA-11) is a positron emission tomography radiopharmaceutical that labels a Glu-urea-Lys-based ligand with ⁶⁸Ga, binding specifically to the PSMA. It is used widely for imaging recurrent prostate cancer and metastases. On the other hand, the preparation and quality control testing of ⁶⁸Ga-PSMA-11 in medical institutions takes over 60 minutes, limiting the daily capacity of ⁶⁸Ge/⁶⁸Ga generators. While the generator provides 1,110 MBq (30 mCi) nominally, its activity decreases over time, and the labeling yield declines irregularly. Consequently, additional preparations are needed, increasing radiation exposure for medical technicians, prolonging patient wait times, and necessitating production schedule adjustments. This study aimed to reduce the ⁶⁸Ga-PSMA-11 preparation time and optimize the automated synthesis system. By shortening the reaction time between ⁶⁸Ga and the PSMA-11 precursor and adjusting the number of purification steps, a faster and more cost-effective method was tested while maintaining quality. The final synthesis time was reduced from 30 to 20 minutes, meeting the standards for the HEPES content, residual solvent EtOH content, and radiochemical purity. This optimized procedure minimizes radiation exposure for medical technicians, reduces patient wait times, and maintains consistent production schedules, making it suitable for clinical application.

• Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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• v.1
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• pp.306-329
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• 2024

Established in 1909, the Imperial Museum was the forerunner of Korean museums, and its collection formed the foundation of today's National Museum of Korea. However, when the Imperial Museum was first established in Changgyeonggung Palace, a zoo and botanical garden were created in addition to the museum. From 1911 onward, these three facilities were collectively referred to as Changgyeongwon Park. The zoo and botanical garden remained at Changgyeongwon when the museum was relocated in 1938, as did some of the items from the collection of the Yi Royal Household Museum. Among them were palanquins used by the royal family and folk items such as armor, as well as taxidermized birds. These stuffed birds were displayed in the corridor of Myeongjeongjeon Hall in Changgyeongwon, and were also displayed in the specimen hall at the back of Myeongjeongjeon Hall. The stuffed birds in particular should prompt a reconsideration of the nature of the Imperial Museum (Yi Royal Household Museum). The museum had been known as a prominent art museum, mainly collecting masterpieces of ceramics (such as Goryeo celadon), Buddhist sculptures, and paintings. However, this character seems to have been just one aspect of the museum. Along with the zoo, which housed live animals, and the botanical garden, which included greenhouses for tropical plants, the museum also featured specimens like taxidermy, suggesting that its initial aim, from a museological perspective, was to be a more comprehensive museum. Notably, Shimogoriyama Seiichi, who managed the general affairs of the museum, collected and cataloged Korean avian specimens from 1908 to 1917. This suggests that the zoo and botanical garden were not merely for entertainment purposes, but also served a museological purpose. However, the Imperial Museum (Yi Royal Household Museum) lacked the essential research and educational functions necessary for a museum, beyond its collecting and exhibition roles. For instance, although specimens of stuffed Korean birds were collected, they were not thoroughly researched. This indicates that while the museum's collection was acquired from a museological perspective, it did not advance into more specialized research. This study aims to examine how the characteristics of the Yi Royal Household Museum have evolved by analyzing the inventory of the museum's collections and the list of Korean bird specimens it held.

• Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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• v.1
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• pp.330-355
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• 2024

There are two main perspectives in Korea on Korean cultural heritage located overseas: one views it as items that need to be repatriated since they were scattered abroad under unfortunate historical circumstances. The other considers them as a means to more widely promote Korea's culture and long history. A shift in perspective has gradually been taking place in the decades since Korea's liberation from Japanese colonial rule in 1945. This can be noted through three major types of exhibitions. The first type is exhibitions of repatriated cultural heritage that showcase items that were illegally removed from the country but later returned or otherwise acquired through purchase or donation. The Special Exhibition of Returned Cultural Heritage, which was held in 1966 on the occasion of the normalization of diplomatic relations between the Republic of Korea and Japan, emphasized the legitimacy of reclaiming cultural properties that were illegally removed from Korea during the period of Japanese colonial rule. Around the 1990s, special exhibitions of private donations were held, which also highlighted the legitimacy of repatriation. The special exhibition of the Oegyujanggak Uigwe (Royal Protocols of the Joseon Dynasty from the Outer Royal Library) held in 2011 was seen as an opportunity to raise public interest in repatriation, heal the wounds of history, and restore the nation's cultural pride. The second type of exhibition involves borrowing and displaying overseas Korean cultural heritage in accordance with a theme as a means to reenergize and provide a comprehensive view of Korean culture. The exhibitions National Treasures from the Goryeo Dynasty in 1995 and National Treasures from the Early Joseon Dynasty in 1997 (both held at the Hoam Museum of Art) and the Masterpieces of Goryeo Buddhist Painting held at the National Museum of Korea in 2010 underscored the importance of overseas Korean cultural heritage for exploring Korean cultural history. The third type is special exhibitions on the history of the collection of Korean cultural heritage. With Korea's economic growth in the 1980s and the increase in exhibitions and the number of galleries featuring Korean cultural heritage in overseas museums in the 1990s, interest in the history of acquisition also grew. Exhibitions like The Korean Collection of the Peabody Essex Museum in 1994 and Korean Art from the United States in 2012 introduced overseas galleries focused on Korean art and the diverse history of collecting Korean cultural properties. They also examined the perception of Korean art in the United States. These efforts heightened public interest in establishing and supporting Korean galleries abroad. The initiation of more systematic surveys and research on Korean cultural heritage located abroad and the contribution of overseas Korean cultural heritage to the enhancement of the local understanding and promotion of Korean culture have resulted in changes to the perception of overseas Korean cultural heritage in Korea.

• Journal of Life Science
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• v.34 no.7
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• pp.476-484
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• 2024

Although two-dimensional (2D) monolayer cell culture models are still widely used as the optimal models for anticancer activity research, three-dimensional (3D) multicellular tumor spheroid (3D MTS) models that can better approximate the tumor environment can offer an alternative to bridge the gap between in vitro and animal model studies. Isoalantolactone is among the sesquiterpene lactones found in medicinal plants, including the roots of Elecampane (Inula helenium L.), and is known to have various pharmacological activities, including anticancer activity. In this study, we investigated whether the anticancer activity of isoalantolactone observed in 2D models could be reproduced in a 3D MTS model derived from human hepatocellular carcinoma (HCC) Hep3B cells. According to our results, isoalantolactone inhibited the formation of MTSs in a manner dependent on the treatment concentration, which was accompanied by an increase in reactive oxygen species (ROS) generation. In particular, as isoalantolactone treatment and the culture time increased, the area of proliferating cells was replaced by cells in which apoptosis was induced. Additionally, in MTSs, isoalantolactone increased the expression of death-receptor-related proteins and the activity of caspase-3, and it decreased the expression of the Bax/Bcl-2 expression ratio and total poly(ADP-ribose) polymerase. However, when the production of ROS was artificially blocked, all these changes caused by isoalantolactone were attenuated and the cell survival rate of MTS cells was restored. Therefore, the results of this study suggest that the induction of apoptosis in Hep3B cell-derived MTSs by isoalantolactone is achieved through the activation of extrinsic and intrinsic pathways and is ROS-dependent.