• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.365-372
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• 2022

Cellobiose is a dissacharide constituted by two glucose units joined by a β-('1,4') glycosidic bond that is produced by the decomposition of cellulose. This product exists naturally in plants and has been utilized in different industries as a food sweetener, and as a cosmetic and pharmaceutical material. In this study, the potential of cellobiose as a whitening cosmetic product was evaluated by analyzing autophagy induction and the inhibition of melanin production. A cytotoxicity test conducted in the human melanin-producing cell line MNT-1 with increasing concentrations of cellobiose revealed that this compound did not cause cytotoxicity at 20 mg/mL or less. Based on this, autophagy was firstly evaluated by immunostaining with the autophagy marker microtubule-associated protein 1 light chain 3 (LC3) after treatment with 20 mg/mL of cellobiose. The subsequent confocal microscopy analysis revealed an increase in LC3 puncta, indicating induction of autophagy. In addition, autophagy was further confirmed by western blot analysis, which demonstrated that cellobiose converted LC3-I to LC3- ∏ in a concentration- and time-dependent manners. An analysis of melanin contents after cellobiose treatment at a concentration of 20 mg/mL during 7 days revealed that melanin production was reduced by more than 50%. Additionally, the expression levels of melanogenesis-related proteins TYR and TYRP1 were markedly decreased after cellobiose treatment. Based on these studies, a cosmetic cream formulation containing cellobiose was prepared and the change in formulation was tested for 4 weeks, and it was confirmed that the appearance changed to liquid form at high temperature, but the pH did not change. In conclusion, the present research demonstrated that cellobiose activates autophagy and inhibits melanin production, and showed the potential of this product as a material for whitening cosmetics.

• Journal of Korean Elementary Science Education
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• v.41 no.4
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• pp.701-724
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• 2022

In this study, the Nature of Science (NOS) instrument for elementary school students in the form of open questionnaires was developed specifically to reveal elementary school students' perceptions of the NOS, and its validity and effectiveness were investigated. To develop a NOS instrument for elementary school students, problems that may occur when applying the existing NOS instruments to elementary school students were analyzed and based on this, the development direction of the NOS instrument was established. In addition, after selecting seven NOS types suitable for the level of elementary school students, the preliminary instrument was produced by modifying and supplementing the items in the existing instruments for each type or by developing new items. Finally, the NOS instrument consisting of eight questions was developed by adding one question asking for a comprehensive understanding of science to seven questions related to each type of NOS after a content validity test of the science education expert group. To verify the practical effect of the developed instrument, pre- and post-tests were conducted on 50 students in two classes of sixth grade at two elementary schools in Seoul: 'existing instrument → development instrument' in one class, and 'development instrument → existing instrument' in the other class. The collected data were then compared and evaluated through summary content analysis and analyzed by executing the Wilcoxon signed-rank test. As a result of comparing and analyzing students' responses to the existing NOS instrument and the developed NOS instrument, students' perspectives on the NOS were more diverse when using the developed instrument, and the level of error in the response caused by misinterpreting the intention of the question was reduced. In addition, when using the developed instrument, the responses of the majority of students at a statistically significant level changed more specifically. In this study, the implications for the development of NOS instruments suitable for elementary school students were discussed based on these results.

• Clean Technology
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• v.28 no.4
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• pp.269-277
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• 2022

With the recent development of the biological enzymatic reaction industry, lactic acid (LA) can be mass-produced from biomass sources. In particular, a catalytic process that converts LA into acrylic acid (AA) is receiving much attention because AA is used widely in the petrochemical industry as a monomer for superabsorbent polymers (SAP) and as an adhesive for displays. In the LA conversion process, NaY zeolites have been previously shown to be a high-activity catalyst, which improves AA selectivity and long-term stability. However, NaY zeolites suffer from fast deactivation due to severe coking. Therefore, the aim of this study is to modify the acid-base properties of the NaY zeolite to address this shortcoming. First, base promoters, Ca ions, were introduced to the NaY zeolites to tune their acidity and basicity via ion exchange (IE) and incipient wetness impregnation (IWI). The IWI method showed superior catalyst selectivity and stability compared to the IE method, maintaining a high AA yield of approximately 40% during the 16 h reaction. Based on the NH₃- and CO₂-TPD results, the calcium salts that impregnated into the NaY zeolites were proposed to exit as an oxide form mainly at the exterior surface of NaY and act as additional base sites to promote the dehydration of LA to AA. The NaY zeolites were further treated with KOH before calcium impregnation to reduce the total acidity and improve the dispersion of calcium through the mesopores formed by KOH-induced desilication. However, this KOH treatment did not lead to enhanced AA selectivity. Finally, calcium loading was increased from 1wt% to 5wt% to maximize the amount of base sites. The increased basicity improved the AA selectivity substantially to 65% at 100% conversion while maintaining high activity during a 24 h reaction. Our results suggest that controlling the basicity of the catalyst is key to obtaining high AA selectivity and high catalyst stability.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.447-455
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• 2022

Fully dehydrated Tl₁₂-LTA (|Tl₁₂|[Si₁₂Al₁₂O₄₈]-LTA,Tl₁₂-A) was treated with 6.0×10³ Pa of ZrI₄ (g) at 623 K for 72 hr under anhydrous conditions. The crystal structure of product, |Zr_0.25I_1.5Tl₁₂|[Si₁₂Al₁₂O₄₈]-LTA, was determined by single-crystal crystallography using synchrotron X-radiation in the cubic space group Pm3m (a = 12.337(2) Å). It was refined using all data to the final error index (for the 712 unique reflections for which F_o> 4σ(F_o) R₁/wR₂= 0.055/0.189. In this structure, octahedral ZrI₆^2- ions center about 25% of the large cavities (Zr-I = 2.91(4) Å). Each coordinates to eight Tl⁺ ions and they are further bridged by Tl⁺ ions in the planes of 8-rings to form a cubic three-dimensional ZrI₆Tl₁₁⁹⁺ cationic cluster. About 1.5 Tl⁺ ions per unit cell moved to deeper side of sodalite cavity after reaction with ZrI₄(g). The remaining Tl⁺ ions occupy well-established cation positions near 6- and 8-rings.

• Journal of Nutrition and Health
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• v.55 no.3
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• pp.376-389
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• 2022

Purpose: Obesity can lead to several chronic diseases. With a continuous increase in the obesity rates, sustainable healthy weight management among growing adolescents has become essential. This study was conducted to examine the relationship between obesity-related factors and creative convergence ability. This could form the basis for convergence education for the sustainable healthy weight management of adolescents. Methods: Data were collected from 430 adolescents in Daegu, Gyeongbuk, and Gyeonggi regions using a self-administered 5-Likert questionnaire from November to December 2020. Results: The average score of the male students was higher than that of the female students in terms of healthy weight management convergence awareness, creativity, convergence thinking ability, self-efficacy, exercise, and dietary diversity. On the other hand, the dietary restraint score and the number of weight loss attempts were higher in the female students. Dietary restraint, disinhibition scores and weight loss attempts were higher in obese adolescents compared to underweight adolescents. It was found that dietary restraint, convergence thinking ability, problem-solving ability, exercise, and dietary diversity factors had a positive effect on healthy weight management convergence awareness. Healthy weight management convergence awareness, exercise, meal amount management, junk food management, weight loss belief, and weight loss trial experience had a positive effect on dietary restraint. Convergence thinking ability, weight loss experience, and obesity factors had a positive effect on dietary disinhibition. Conclusion: The sustainable healthy weight management education of adolescents is based on weight management knowledge and awareness of convergence, and must include gender differences. Thus, the problem-solving ability for healthy weight management can be creatively cultivated to enhance self-efficacy.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.214-230
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• 2022

This paper discusses the characteristics and background of the production of white porcelain with the "Byeol(別)" inscription. Such porcelain was produced by the government-run porcelain kiln, Gwanyo(官窯), in the 16th and 17th centuries (from the 1560s to the 1640s), during the Joseon dynasty. The white porcelain ware, inscribed with either the term Byeol or "jwa(左)" and "u(右)," constituted a dual production system of white porcelain by Gwanyo starting in the 1560s. However, to date, few studies have examined Byeol-inscribed white porcelain. This, therefore, makes it difficult to achieve a comprehensive understanding of the evolution of inscriptions on the white porcelain produced by Gwanyo in the 15th to 17th centuries. Besides a regular annual stock of porcelain(年例進上磁器), Gwanyo also produced and supplied additional porcelain ware, or Byeol-gi, at the behest of the royal family or the court of Joseon. Byeol-inscribed white porcelain is a form of Byeol-gi, produced through extra firing, or Byeolbeon(別燔). According to use, Byeol-gi can be categorized as an item for national use(國用) or an item for internal use(內用). However, if the porcelain only carries the "Byeol(別)" inscription, it is difficult to identify its characteristics. Furthermore, as part of the annual production of porcelain was for the supply of Byeol-gi, and then for other purposes, the white porcelain came to be inscribed with dots indicating a change in ownership. In the 16th century, the royal family increased its consumption of white porcelain based on Shinyu Gongan(辛酉貢案), the government's fiscal reform measures. To guarantee a stable supply of exceptional Byeol-gi in light of Gwanyo's decline in the 1560s, the royal family benefited from the inscription of "Byeol." The white porcelain produced by Gwanyo was divided into annual offerings-those with the inscriptions "jwa(左)" and "u(右)"-and Byeol-gi, those with the inscription of "Byeol." They were managed separately from the commencement of production. Byeol-inscribed white porcelain was produced until the 1640s. During the mid-and late 1640s, Byeolbeon was temporarily suspended. Starting in the 1650s, the white clay used to produce the annual stock of white porcelain was sourced from regions other than those providing the clay for Byeol-gi production. The former used clay from Wonju(原州土) and Seosan(瑞山土), while the latter used clay from Gyeongju(慶州土) and Seoncheon(宣川土). According to the literature, the clay from Gyeongju and Seoncheon was much cleaner than that from Wonju and Seosan. Byeolbeon thus underwent a transformation, whereby production was separately managed, right from the stage of white clay mining. Ultimately, the need for the separate management of Byeol-gi through inscriptions diminished, resulting in the disappearance of Byeol-inscribed white porcelain.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.146-165
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• 2022

The purpose of this study is to identify differences in the formative characteristics and system of Jobok by comparing the three relics Ui, Sang, and Daedae, which comprised Jeon-Sik's Jobok, with the data in the literature and five excavated Jobok relics, Sin Kyung-yu, Kwon-Woo, Hwasan-Gun, Milchang-Gun, and Lee Ik-jeong, from the 17th and 18th centuries. Jeon-Sik'sJobok was designated as a Gyeongbuk tangible cultural heritage, Sangju JeonSik Jobok and Crafts, in 2021. The three components of Jeon-Sik's Jobok are valuable as historical data since they are the oldest relics confirming colors. Regrettably, the edging fabric of the Ui made of red twill was mostly lost, with only traces remaining. Based on records, it was presumed that the edging fabric was black. It was confirmed that white decorative lines were yet to be used. In Jeon Sik's Sang, only the three front widths and one rear width remain, but the shape of the four rear widths can be inferred, and the creases were held only at the waist. Eighteenth-century Sang was connected at intervals at the end of the waist. Seventeenth-century Sang was connected with a slight overlapping of the rear Sang below the front Sang; therefore, it is assumed that Jeon Sik's Sang was also connected by overlapping the rear by more or less than 5cm below the front. After Hwasan-gun, the Sang was first made using black lines, then white lines were inserted, and, finally, it was pleated from the waist to the hem. The Daedae made the Yo and the Sin by folding the corners to form a 冂 shape with a single long band. The white Ju(紬) and the green yumunsa were used for the Daedae and the edges. This matches the color of the Daedae seen in the Jobok portraits of Milchang-gun, Lee Ik-jeong, and Jeong Hwi-ryang from the 18th century. In the 17th century, the Daedae made the Yo and the Sin by folding a long band like the Daedae of Jeon-Sik. After the 18th century, the Yo and the Sin were made separately and connected. To tie the Daedae to the waist, thin straps were attached at both ends. The relics of Jeon-Sik can be evaluated as reflecting the 17th-century Jobok system in terms of color and shape. Furthermore, it can be said that they are important historical data complementing the insufficient or inaccurate records of the Gukjoolyeui-seolye and Gyeongguk-daejeon.

• Journal of Conservation Science
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• v.37 no.6
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• pp.723-737
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• 2021

This study analyzed the composition and structure of materials with Buddhist paper scriptures excavated from architectural sites in 'Sum Tolgoi' of the 17^th century and carried out conservation treatment base on the result of the analysis. The scriptures were covered in dust and foreign sub stances, and were so crumpled that it was impossible to identify the form. The damage, loss, and discoloration have been identified. Buddhist scriptures written in Tibetan used indigo and ink sticks on paper as a result of UV-Vis analysis, and ink sticks as black character materials from scriptures written ancient Mongolian. SEM-EDS and Micro-XRF analyses revealed that the outlines were drawn with red lines using a mix of Minium (Pb₃O₄) and Cinnabar (HgS), or Cinnabar (HgS) alone, and the contents of the scriptures were written with silver paint. Silver chloride (AgCl) and Calcium (Ca) were identified in the silver paint component of the characters, while Calcium and Orpiment (As₂S₃) were identified in the yellow lines. Concerning the paper ground, Buddhist scriptures written in ancient Mongolian were characterized by herbal plant fiber and bast fiber, and those written in Tibetan, by bast fiber. Radiocarbon dating indicates that the paper for the scriptures was produced between the 15^th and 17^th centuries. Conservation treatment of the scriptures was carried out based on the experiment on the production of pre-coated paper and how to coat that to prevent the second damage due to the deformation and fragility of the excavated paper. The scriptures were preserved and mounted, and a neutral box was made to identify the contents of the scriptures recorded on both sides after the treatment. This conservation treatment is the result of a study that applied new conservation treatment materials and methods according to the principle of conservation treatment reversibility.

• Resources Recycling
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• v.31 no.1
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• pp.65-77
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• 2022

A study was conducted in Korea on the leaching behavior and possibility of recovery of vanadium and other valuable metals from domestic vanadium titanomagnetite (VTM) by direct acid leaching. In this study, a VTM concentrate containing 0.8% V₂O₅ was used, and the ratio of magnetite to ilmenite was calculated as 1.9:1 by using the HSC program. The leaching behavior of vanadium from the VTM was similar to that of iron, and it was affected by the concentration of sulfuric acid and temperature. Further, titanium could be leached in the form of TiOSO₄ at a temperature higher than 75℃. To improve the leaching efficiency of V, Fe, and Ti in VTM, reductive sulfuric acid and oxidative sulfuric acid leaching were performed. When Na₂SO₃ was used as a reducing agent, the leaching rate of vanadium was 80% of that in that case of leaching by sulfuric acid. Similarly, the leaching rate of titanium increased from 20% to 50%. When Na₂S₂O₈ was used as an oxidation agent, most of the vanadium was leached, and the main residue found by XRD analysis was ilmenite. In studies on the possibility of recovering valuable metals, the selective extraction of metals is hardly achieved by solvent extraction from oxidation leaching solutions; however, in this study, Cyanex 923, a solvation extractant from reductive leaching solutions, could selectively extract Ti.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.1
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• pp.33-52
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• 2022

The History and Culture Park and the Lee Kun-hee Donation Hall will be built in Songhyeon-dong, Seoul. Political games from the Joseon Dynasty to the present greatly influenced the historicity of Songhyeon-dong. However, place analysis was limited to changes in landowners and land uses rather than a historical context. Therefore, this study analyzed the context in which the placeness of Songhyeon-dong changed according to the emergence of cultural hegemony using the perspective of modern cultural geography and comparative history. As a result of the analysis, cultural hegemony in historical transitions, such as Sinocentrism, maritime expansion, civil revolutions, imperialism, nationalism, popular art, and neoliberalism, was found to have created new intellectuals in Bukchon, including Songhyeon-dong, and influenced social systems and spatial policies. In this social relations, the placeness of Songhyeon-dong changed as follows. First, the founding forces of Joseon created pine forests as Bibo Forests to invocate the permanence of the dynasty. In the late Joseon dynasty, it was an era of maritime expansion, and as Joseon's yeonhaeng increased, a garden for the Gyeonghwasejok, who enjoyed the culture of the Qing dynasty, was built. Although pine forests and gardens disappeared due to the development of housing complexes as the population soared during the Japanese colonial era, Cha Gyeong's landscape aesthetics, which harmonized artificial gardens and external nature, are worth reinterpreting in modern times. Second, the wave of modernization created a new school in Bukchon and a boarding house in Songhyeon-dong owned by a pro-Japanese faction. Angukdongcheon-gil, next to Songhyeon-dong, was where thinkers who promoted civil revolution and national self-determination exchanged ideas. Songhyeon-dong, the largest boarding house, served as a residence for students to participate in the March 1st Movement and was the cradle of the resulting culture of student movements. The appearance of the old road is preserved, so it is a significant part of the regeneration of walking in the historic city center, connecting Gwanghwamun-Bukchon-Insadong -Donhwamunro. Third, from the cultural rule of the Government General of Joseon to the Military Government, Songhyeon-dong acted as a passage to western culture with the Joseon Siksan Bank's cultural housing and staff accommodations at the U.S. Embassy. Ancient and contemporary art coexisted in the surrounding area, so the modern and contemporary art market was formed. The Lee Kun-hee Donation Hall is expected to form a cultural belt for citizens with the gallery, Bukchon Hanok Village, the Craft Museum, and the Modern Museum of Art. Discourses and challenges are needed to recreate the place in harmony with the forests, gardens, the street of citizens' birth, history and culture park, the art museum, and the surrounding walking network.