• Membrane Journal
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• v.34 no.1
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• pp.30-37
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• 2024

As a promising method to address global water scarcity, sorbent-assisted water harvesting from air has shown great potential to deliver drinking water for inlands lacking traditional water sources. In this article, the recent studies of using metal-organic frameworks (MOFs) as sorbents to harvest atmospheric water will be introduced. Compared to the other sorbent materials such as zeolites or silica-based materials, MOFs have shown prospective properties such as the water isotherm inflection points as low as ~10%, which are suitable for harvesting water at dry regions. Due to this property, recently, MOFs have been extensively adopted to develop practical water harvesting devices that can harvest water. Since atmospheric water is accessible anywhere and anytime in the world, this technology is expected to open a new avenue in terms of securing safe water for the future.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.4
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• pp.12-24
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• 2020

The purpose of this study is to analyze the influence of the water system on the location, spatial structure, and construction method of Hongju-eupseong, centering on Hongjumok-eupchi. During the Joseon Dynasty, the water system in Hongjumok-eupchi is composed of artificially constructed Seong-an Runnel and ponds based on a branch-shaped natural waterways flowing from south to north and west to east. Compiling the results of various literature records, excavations and analysis of map data, it can be seen that the water system has an important influence on the construction of Hongju-seong. Firstly, Hongju-seong from the Goryeo Dynasty to the late Joseon Dynasty is located using a circular shape of topographical structure and a small erosion basin formed on the inner side of the Hongseongcheon and Wolgyecheon streams without significant change in location. In particular, Wolgyecheon and Hongseongcheon are natural moats, which are harmonized with Sohyangcheon and riverside topographical structures, affecting the location and construction method of Hongju-seong, water related facilities, and the spatial structure of eupseong. It is understood that location characteristic of Hongju-seong reflects the urban location structure harmonized with waterways in ancient China and Korea. Secondly in harmony with the water system and topographic structure of Hongju-seong, it is an important factor in deciding the land use of the town, the arrangement of the town hall facilities and inducing various non-subsidiary measures such as the establishment of embankment forest with a secret function and the closure of the south gate. In addition, artificial drainage facilities such as Seongan runnel and ponds are being actively introduced from early on to protect the walls or towns from flooding of Wolgyecheon. Especially there were typical methods for protecting the walls from water damage such as the Joseon Dynasty stone castle structure that was integrated with saturn(soil wall) in the Goryeo Dynasty, retreating wall in the northern gate area in the late Joseon Dynasty, and the method of constructing wall using korean tile and stone floors between reinforced soil layers in the western and northern wall.

• Development and Reproduction
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• v.4 no.2
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• pp.161-173
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• 2000

The aim of this study was to assess the effect of the frequency of the L$N_2$ infusion on the ultrastructure, metabolism and development of the embryo after freezing and thawing by computerized cell freezer. Two-cell embryos of ICR mouse were randomly allocated into fresh (control), high-frequency freezing (group 1) and low-frequency freezing (group 2). For fresh and frozen-thawed intact 2-cell embryos, total ceil number in the blastocyst was counted by fluorescent microscope after Hoechst 33258 staining. Relative amount of $H_2O$$_2$ was measured by DCHFDA. Intracellular location and membrane potential of the mitochondria were evaluated by staining with rhodamine 123 and JC-1. The structure of actin filament was also evaluated by confocal microscope. DNA fragmentation was assessed by TUNEL method after development into blastocyst. The survival rate of intact embryo was higher in group 1 than group 2 (50.7％ vs. 34.6％ respectively, p<0.05). The blastocyst developmental rate was significantly low in group 2 (86.7％, 76.7％ vs. 44.0％ for control, group 1 and group 2 respectively, p<0.05). Total cell number in the blastocyst was also significantly lower in group 2 than control (79.5$\pm$12.9, 71.6$\pm$8.0, and 62.5$\pm$4.7 for control, group 1 and group 2 respectively, p<0.05). The relative amount of $H_2O$$_2$ was higher in group 2 than other groups (15.3$\pm$3.0, 16.6$\pm$1.6 vs. 23.4$\pm$1.8, p<0.05). After JC-1 staining, relative intensity of mitochondria with high membrane potential was significantly lower in group 2 than control and group 1 (17.2$\pm$3.8, 17.4$\pm$1.3 vs. 13.2$\pm$2.0, p<0.05). In group 2, partial deletion and aggregation of the actin filament was found. DNA fragmentation rate was also hieher for group 2 versus other groups (30.8％, 36.0％ vs. 65.6％, p<0.05). The frequency of the L$N_2$ infusion is an important factor for the development of frozen-thawed mouse embryo. High-frequency infusion may prevent damages of cytoskeleton and mitochondria in the embryo probably by preventing the temperature fluctuation during dehydration phase. We speculate that the application of high-frequency infusion method in human embryo may be promising.

• Economic and Environmental Geology
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• v.53 no.1
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• pp.1-9
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• 2020

Magnesium silicate minerals such as serpentine [Mg₃Si₂O₅(OH)₄] have a high potential for the sequestration of CO₂; thus, their reactivity toward dissolution under CO₂-free and CO₂-containing conditions in acidic solvents is a critical process with respect to their carbonation reactions. To examine the carbonation efficiency and dissolution mechanism of serpentine, hydrothermal treatment was performed to the starting material via a modified direct aqueous carbonation process at 100 and 150℃. The serpentine dissolution experiments were conducted in H₂SO₄ solution with concentration range of 0.3-1 M and at a CO₂ partial pressure of 3 MPa. The initial pH of the solution was adjusted to 13 for the carbonation process. Under CO₂-free and CO₂-containing conditions, the carbonation efficiency increased in proportion to the concentration of H₂SO₄ and the reaction temperature. The leaching rate under CO₂-containing conditions was higher than that under CO₂-free conditions. This suggests that shows the presence of CO₂ affects the carbonation reaction. The leaching and carbonation efficiencies at 150℃ in 1 M H₂SO₄ solution under CO₂-containing conditions were 85 and 84%, respectively. The dissolution rate of Mg was higher than that of Si, such that the Mg : Si ratio of the reacted serpentine decreased from the inner part (approximately 1.5) to the outer part (less than 0.1). The resultant silica-rich layer of the reaction product ultimately changed through the Mg-depleted skeletal phase and the pseudo-serpentine phase to the amorphous silica phase. A passivating silica layer was not observed on the outer surface of the reacted serpentine.

• Journal of Life Science
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• v.24 no.12
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• pp.1276-1283
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• 2014

Cell adhesion molecules determine the cell-cell binding and the interactions between cells and extracellular signals. Cell-cell junctional complexes, which maintain the structural integrity of tissues, consist of more than 50 proteins including multi-PDZ domain protein 1 (MUPP1). MUPP1 contains 13 postsynaptic density-95/disks large/zonula occludens-1 (PDZ) domains and serves a scaffolding function for transmembrane proteins and cytoskeletal proteins or signaling proteins, but the mechanism how MUPP1 links and stabilizes the juxtamembrane proteins has not yet been elucidated. We used the yeast two-hybrid system to identify proteins that interact with PDZ domains of MUPP1. We found an interaction between MUPP1 and cell adhesion molecule 1 (Cadm1, also known as SynCAM1, Necl-2, or TSLC1). Cadm1 bound to the second PDZ domain of MUPP1. The carboxyl (C)-terminal end of Cadm1 has a type II PDZ-association motif (-Y-F-I) which was essential for the interaction with MUPP1 in the yeast two-hybrid assay. MUPP1 also bound to the C-terminal cytoplasmic tail region of other Cadm family members (Cadm2, Cadm3, and Cadm4). In addition, these protein-protein interactions were observed in the glutathione S-transferase (GST) pull-down assay and by co-immunoprecipitation. Anti-MUPP1 antibody co-immunoprecipitated Cadm1 and Cadm4 with MUPP1 from mouse brain extracts. These results suggest that MUPP1 could mediate interaction between Cadms and cytoskeletal proteins.

• Applied Microscopy
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• v.41 no.4
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• pp.277-284
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• 2011

This study was conducted to determine the antiseptic effect of stabilized chlorine dioxide (S-$ClO_2$) on muscle tissue of rats. Skeletal muscle of 8-week old Sprague-Dawley rats was used. Light and transmission electron microscopic findings were observed in the control group, which was not treated with stabilized chlorine dioxide, and in the experimental group, which was treated with a stabilized chlorine dioxide powder in aqueous solution. According to the LM and TEM observations, the day 1 control group showed the initiation of endomysium collapse resulting in an unclear boundary of muscle fibers, and partial collapse of the mitochondrial membranes. All endomysium had collapsed, and bacteria were observed among muscle fibers in the day 2 and later groups. Shapes of muscles were not distinguishable in day 3 or later groups. In contrast, the day 1 and 3 experimental groups revealed detailed structure of typical muscles, but partial collapse of the mitochondrial membranes was observed in the day 3 and later groups. Subsequently, connective tissues collapsed and structures in the shape of concentric circles were observed. In summary, the day 1 control group showed the initial collapse of tissues, and shapes were not distinguishable in the day 3 and later groups because most of the tissues had collapsed. In contrast, the day 3 experimental group showed partial collapse, but the overall shapes of muscles were maintained as time went on, confirming the antiseptic effect of stabilized chlorine dioxide on muscles.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.3
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• pp.169-176
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• 2021

This study aimed to fundamentally understand structural changes of zeolite under pressure and in the presence of different pressure-transmitting media (PTM) for application studies such as immobilization of heavy metal cation or CO₂ storage using pressure. High-pressure X-ray powder diffraction study was conducted on the zeolite-W (K_6.4Al_6.5Si_25.8O₆₄× 15.3H₂O, K-MER) to understand linear compressibility and the bulk moduli in different PTM conditions. Zeolite-w is a synthetic material having the same framework as natural zeolite merlinoite ((K, Ca_0.5, Ba_0.5, Na)₁₀ Al₁₀Si₂₂O₆₄× 22H₂O). The space group of the sample was identified as I4/mmm belonging to the tetragonal crystal system. Water, carbon dioxide, and silicone-oil were used as pressure-transmitting media. The mixture of sample and each PTM was mounted in a diamond anvil cell (DAC) and then pressurized up to 3 GPa with an increment of ca. 0.5 GPa. Pressure-induced changes of powder diffraction patterns were measured using a synchrotron X-ray light source. Lattice constants, and bulk moduli were calculated using the Le-Bail method and the Birch-Murnaghan equation. In all PTM conditions, linear compressibility of c-axis (𝛽^c) was 0.006(1) GPa^-1 or 0.007(1) GPa^-1. On the other hand, the linear compressibility of a(b)-axis (𝛽^a) was 0.013(1) GPa^-1 in silicone-oil run, which is twice more compressible than the a(b)-axis in water and carbon dioxide runs, 𝛽^a = 0.006(1) GPa^-1. The bulk moduli were measured as 50(3) GPa, 52(3) GPa, and 29(2) GPa in water, carbon dioxide, and silicone-oil run, respectively. The orthorhombicities of ac-plane in the water, and carbon dioxide runs were comparatively constant, near 0.350~0.353, whereas the value decreased abruptly in the silicone-oil run following formula, y = -0.005(1)x + 0.351(1) by non-penetrating pressure fluid condition.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.22-47
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• 2014

This study was to understand the basic principles of the East Asian wooden structure system research and analysis. The Korea and China ancient architecture internal structure research that the combination of girders and crossbeams position. The ancient wooden structures of eastern Asian countries, Korea and China are not much different from each other in the principles of the wooden architecture structure, combining pillars, purlins and crossbeams. However, it seems that age-division, local-division, national-division differs in detail techniques. China ancient wooden structures combination of purlin and crossbeam, and So-seul Timber(Chinese name: Chashou叉手, Tuojiao 托脚) seems to show differences according to the age of the fulcrum position, detailed approach is also different according to various historical dynasty. Before in the 15th century, Purlin and Crossbeam are coupled to each other, but since the 15th century, seems to have developed a technique combined with each other Girder and Crossbeam and to prevent buckling of the Crossbeam cross-sectional area increased dramatically. For Tuojiao in China Tang-Wudai dynasty(A.D. 618~979), can see that saw the top position Girder and Tuojiao no direct coupling, can be seen as maintaining the safety of the material than the material of the inner wooden structures prevent buckling of the purlin. Korea ancient wooden structures of Goryeo dynasty(A.D. 918~1391), So-seul Timber(Chinese name Tuojiao) why do not to use the fashion? To use Purlin Lower backing material techniques to prevent buckling is a popular trend to stable can be thought of as a preferred way to maintain. I think that with universality beyond the local-division, national-division and the two countries since the 15th century of Korea and China ancient wooden structures detailed mechanism for the purlin buckling. In middle-late Chosen dynasty, The effect of Deotgeolyi- techniques and fleeting beams reduce the purlin buckling that reduces the load transmitted from purlin and crossbeam of how to reduce the load on the roof portion of the architecture fleeting beams used, which of craftsmanship of the Chosen Dynasty building can be referred to as another technique for preventing buckling purlin. This Korea and China ancient architecture purlin beam structure and material So-seul Timber study. Seems to be able to provide a basic research study to restore and designed the old wooden architectures.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.4
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• pp.99-110
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• 2021

This study intends to examine the characteristics of the construction method of the urban water system in the historical cities of Korea, focusing on Gyeongju, Gyeongju, Goryeo, Hanyang, and Suwon Hwaseong, which were created as new towns in the late Joseon Dynasty. It examines the meaning of waterways in connection with the urban skeletal structure, focusing on the location of cities, roads, and arrangement of urban facilities, and analyzes the compositional form of the water system. We tried to derive the relationship with the structure. In particular, it can be seen that water and natural water systems act as key factors in determining the location of a city, and have a close relationship with the urban structure, urban development process, and urban structure. In addition to the symbolic meaning of water in harmony with the geographical concept, realistic demands in terms of water level and water retention are an important background. In order to respond to various demands related to water space, various planning and technical elements for managing water space were introduced in the process of city formation and development. The planning elements of the urban water system in the process of urban formation and development are summarized as follows through the analysis of the research site. First, in the process of building the urban water system in Gyeongju, Goryeo, Goryeo, Hanyang, and Hwaseong, Suwon, which were selected as the research destinations, the water system in consideration of drainage and disaster is common, but the water system construction method and usability are common. shows the difference. Second, water and natural water systems act as symbolic elements to secure the legitimacy of the city location, and as a key factor in determining the location of the city in harmony with the geographical concept and determining the left direction of the city. Third, the natural water system prior to the formation of a city works as a basis for determining the compositional form of the urban water system constructed in the process of urban formation and development in harmony with the topographical conditions. Fourth, the urban water system built on the basis of natural water systems is constructed by linking natural waterways and planned artificial waterways. Fifth, the urban water system is being built in a planned manner in consideration of the utility in connection with the urban structure, such as securing of urban land, arrangement of urban facilities and areas, composition of functional areas, and land division, in addition to the perspective of drainage system and flood control in consideration of disasters.

• The korean journal of orthodontics
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• v.30 no.5 s.82
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• pp.643-655
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• 2000

In Patients with severe skeletal discrepancy, surgical orthodontic treatment must be accompanied, and recently two jaw surgery has become a common procedure, resulting in improved esthetics and function. Choosing the position of the occlusal plane in this two jaw surgery is an important factor in postoperative stability Therefore this must be taken into consideration during the diagnosis and treatment plan. In this study, among patients with skeletal Class III occlusion, 25 patients(8 male, 17 female, average age $23.2{\pm}3.17$) who have undergone two jaw surgery, setting the ideal occlusal plane according to Delaire's architectural and structural cranial analysis. In comparing preoperative($T_1$). postoperative($T_2$, average of 15.4 days), and long-term postoperative($T_3$, average of 32.6 months) lateral cephalometric radiography, the following conclusions have been made. 1. There were no significant changes of the occlusal plane angle after the two jaw surgery, and there were no significant differences between the surgical technique(SSRO and IVRO). 2. The postoperative changes of the occlusal Plane had no relationship with the amount of jaw movement, amount of posterior impaction, nor the time relapse after surgery. 3. After two jaw surgery, in the SSRO group there was significant forward movement of the mandible, and in the IVRO group the lower incisors extruded as the mandible moved backward and downward which makes the genial angle and the mandibular plane angle significantly increased