• Korean Journal of Materials Research
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• v.32 no.11
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• pp.481-488
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• 2022

The Cu₂ZnSn(S_xSe_1-x)₄ (CZTSSe) absorbers are promising thin film solar cells (TFSCs) materials, to replace existing Cu(In,Ga)Se₂ (CIGS) and CdTe photovoltaic technology. However, the best reported efficiency for a CZTSSe device, of 13.6 %, is still too low for commercial use. Recently, partially replacing the Zn²⁺ element with a Cd²⁺element has attracting attention as one of the promising strategies for improving the photovoltaic characteristics of the CZTSSe TFSCs. Cd²⁺ elements are known to improve the grain size of the CZTSSe absorber thin films and improve optoelectronic properties by suppressing potential defects, causing short-circuit current (J_sc) loss. In this study, the structural, compositional, and morphological characteristics of CZTSSe and CZCTSSe thin films were investigated using X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF), and Field-emission scanning electron microscopy (FE-SEM), respectively. The FE-SEM images revealed that the grain size improved with increasing Cd²⁺ alloying in the CZTSSe thin films. Moreover, there was a slight decrease in small grain distribution as well as voids near the CZTSSe/Mo interface after Cd²⁺ alloying. The solar cells prepared using the most promising CZTSSe absorber thin films with Cd²⁺ alloying (8 min. 30 sec.) exhibited a power conversion efficiency (PCE) of 9.33 %, J_sc of 34.0 mA/cm², and fill factor (FF) of 62.7 %, respectively.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.19-26
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• 2018

Objectives : The aim of this study was to investigate the immunopotentiating activity of combine extract that Silkworm and Cinnamomum cassia. Recently, acute epidemic diseases such as cold and viral respiratory diseases have been emerging. So, interested in immunity enhancement has been increasing, and research on natural products to promote immunity activity has been actively conducted. Methods : To confirm the immunopotentiating activity effect, Silkworm (SW), Cinnamomum cassia (CC), and SWCC combined extracts were treated 14 days at 300 mg/kg/day. The changes of glutamic oxalacetic transaminase (GOT), glutamic pyruvate transaminase (GPT) in serum were analyzed after experiment. The changes in the total spleen cell number were measured. Immune cells in spleen were analyzed using fluorescence activated cell sorter (FACS). also, analyzed the expression of cytokines in spleen. Results : Total number of cells in the spleen and FACS analysis of T lymphocytes activated in the spleen showed that the SWCC combined treated group had much higher frequency of active cells than both single groups. The ratio of CD4+CD8+, CD4+CD69+ and CD4+CD25+ T cells in spleen, SWCC is higher than other groups except Nor in CD4+, CD4+CD69+, CD4+CD25+ T cells. The results of this study suggest that SWCC can help immune function via IL-2, IL-10, IL-12, IFN-${\gamma}$ cytokine production, increased T lymphocytes and splenocyte proliferation. Conclusion : Therefore, these results suggested that the SWCC combined extracts administration increase stronger immunity enhancement than when SW and CC adminstration.

• Journal of Life Science
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• v.32 no.2
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• pp.148-154
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• 2022

Focal adhesion kinase (FAK) is known to regulate cell adhesion, migration, and mechanotransduction in focal adhesions (FAs). However, studies on how FAK activity is regulated in the plasma membrane microdomains according to the composition of extracellular matrix (ECM) proteins are still lacking. A genetically encoded fluorescence resonance energy transfer (FRET)-based biosensor can provide useful information on the activity of intracellular signals with high spatiotemporal resolution. In this study, we analyzed the FAK activities in lipid raft (detergent-resistant membrane) and non-lipid raft (non-detergent-resistant membrane) microdomains using FRET-based membrane targeting FAK biosensors (FAK-Lyn and FAK-KRas biosensors) under four different ECM protein compositions: glass, type 1 collagen, fibronectin, and laminin. Interestingly, FAK activity in response to laminin in a lipid raft microdomain was lower than that in other ECM conditions. Cells subjected to fibronectin showed higher FAK activity in a lipid raft microdomain than that in a non-lipid raft microdomain. Therefore, this study demonstrates that the FAK activity can be distinctively regulated according to the ECM type and the environment of the plasma membrane microdomains.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.1
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• pp.7-11
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• 2022

Recently, Hanmi Gemological Institute & Laboratory (HGI) had an opportunity to examine 5 transparent synthetic moissanite. The round brilliants ranged from 0.93 to 0.96 ct and had a colorless, pink, yellow, blue, and red color. Advanced testing results, including Fourier-transform infrared (FTIR) and Raman spectroscopy, identified all the specimens as synthetic moissanite. Under the microscope, all samples except the colorless were confirmed to be a synthetic moissanite coated with a colored film. EDXRF chemical analysis detected very weak X-ray fluorescence peak characteristics of Ca, Ti, and Co in the colored samples. These features were not detected in the colorless sample. Raman spectroscopy investigation was unable to detect the 1332 cm^-1 (produced by sp³ bonding of carbon atoms) or the ~1550 cm^-1 (produced by graphite-related sp² bonding) peak in the colorless sample. The SEM image of the colorless sample showed no indication of a coating. The TEM image of the colorless sample revealed the presence of a 3~8 nm thick layer on the moissanite. Moreover, from the corresponding STEM Z-contrast image combined with the energy-dispersive X-ray spectroscopy (EDX) line profiles and EDX elemental maps, this layer was estimated to be carbon, silicon and oxygen.

• Korean Journal of Animal Reproduction
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• v.25 no.4
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• pp.305-315
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• 2001

In this study, the production of transgenic embryo was attempted by microinjection or round spermatid cultured with foreign DNA. At first, the expression of haploid spermatids specific gene, mTP1 in mouse and hPrm2 in hamster spermatids were investigated by RT-PCR method in testes of young mice and hamster testis. The specific gene expression first appeared at 18 days post partum (dpp) in mice spermatid and 20 dpp in hamster spermatid. Therefore, the round spermatids isolated from 17 dpp mice and 19 dpp hamster were used for the introduction of foreign EGFP gene into haploid round spermatids. For the introduction of EGFP gene haploid round spermatids suspended in medium including EGFP gene were treated with a different electric field strength at 0.11, 0.18 and 0.44 ㎸/cm. After electrical stimulation, viability of testicular sperm cells and 67.6%, 66.4% and 49.9%, in mice and 62.6%, 57.9% and 27% in hamster, respectively. These values were significantly lower than those of non-treated control groups 80.5% in mouse and 69.1% in hamster After 72 hrs culture, the highest expression rate of EGFP gene, 28.5% in mice and 32.1% in hamster were obtained from tile spermatogenic cells electroporated by the field strength or 0.18 ㎸/cm. Then, the ability of fertilization and embryonic development of haploid spermatids transfected with foreign EGFP gene were estimated by the microinjection of spermatids into hamster oocytes. The Irate pronuclear formation rate (77.5%) was lower than non-treated control (80%), and the cleavage rate of the treated group (58.8%) was lower than control (65%). To prove the foreign EGFP integration in hamster embryos, 2-cell stage hamster embryos were subjected to the observation under the fluorescence microscope, and the PCR analysis. As a result, about 44% of 2-cell embryos were showed the integration of EFGP gene into their genome. Therefore, These results suggest the possibility to produce transgenic hamsters by microinjection of haploid spermatid transfected with foreign DNA.

• Analytical Science and Technology
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• v.22 no.1
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• pp.109-117
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• 2009

The following concentrations of some PAHs were investigated; [benzo(a)anthracene, chrysene, benzo (b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g, h, i)perylene, indeno (1,2,3-c,d)pyrene] in fish(n=168) and shellfish(n=40). The methodology involved saponification and extraction with n-hexane, clean-up on Sep-Pak Florisil Cartridges and determination by HPLC/FLD (High Performance Liquid Chromatograph/Fluorescence Detector). Overall method recoveries for 8 PAHs spiked into these products ranged from 88 to 112%. The mean level of benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k) fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene and indeno(1,2,3-c,d)pyrene in cooked fish was ND, ND, 0.0009, ND, 0.01, ND, ND, ND and in cooked shellfish was 1.84, 3.51, 0.81, 0.38, 0.39, 0.04, 0.20, ND, respectively.

• Korean Journal of Poultry Science
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• v.50 no.4
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• pp.261-266
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• 2023

The skeletal muscles of livestock play a crucial role as protein sources for humans, and the consumption of poultry meat is steadily increasing worldwide. Numerous genes, including myogenic regulatory factors, are involved in myogenesis, and precise regulation of them is essential. In this study, genes specifically expressed in muscles were selected, and their promoters were cloned and analyzed. The analysis of gene expression in various tissues of animals revealed that many genes exhibited specific expression patterns in skeletal muscles, with TNNT3, TNNC2, and MYF6 genes showing similar patterns in poultry. The promoter regions of three genes were amplified by polymerase chain reaction to sizes of 1.2 kb, 1.03 kb, and 1.43 kb, respectively. These fragments were then inserted at the front of the enhanced green fluorescent protein gene in vectors. It was confirmed that the sequences of three promoters closely matched the chicken genome sequences. Upon introducing vectors with each promoter into QM7 quail muscle cells, all three promoters successfully induced the expression of the green fluorescent protein. The brightness of the green fluorescence in each promoter was approximately seven times dimmer compared to the control, CMV-IE promoter. It is predicted that more than 230 transcription factors can bind to each promoter, especially various transcription factors expressed in muscles, including myogenic regulatory factors such as MYF5, MYOD, and MYOG. These promoters can be valuable for studying gene expression in poultry muscle cells, and further research is needed to precisely investigate the regulatory region of gene expression in promoters.

• Herbal Formula Science
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• v.32 no.1
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• pp.63-82
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• 2024

Objective : Saengkankunbi-tang (SKT) is used as a traditional Korean herbal formula for treatment of liver diseases. We investigated the hepatoprotective effects of SKT plus Epimedium koreanum Nakai (EKE) against arachidonic acid (AA) + iron-mediated cytotoxicity in HepG2 cells and carbon tetrachloride (CCl₄)-mediated acute liver damage in mice. Methods : The cyto-protective effects of SKT + EKE were determined by MTT assay, western blot and fluorescence activated cell sorting analysis. In mice, blood biochemistry and western blot were assessed in CCl₄-induced acute hepatic damage. The animal groups included vehicle-treated control, CCl₄, SKT (200 mg/kg/day), EKE (100 mg/kg/day), SKT (200 mg/kg/day) + EKE (100 mg/kg/day) and silymarin (200 mg/kg/day). Results : In HepG2 cells, pretreatment with SKT + EKE significantly suppressed cytotoxicity induced by AA + iron and reduced the expression of proteins related to apoptosis. In addition, pretreatment with SKT + EKE significantly prevented the increase in H₂O₂ production, GSH depletion, and lower mitochondrial membrane potential induced by AA + iron. In CCl₄-induced liver damage mice, the administration of SKT + EKE prevented the liver damage by inhibition of hepatocyte damage and expression of apoptosis proteins in liver. More importantly, in vitro and in vivo assay, SKT + EKE showed significant effect compare with SKT alone or EKE alone in all parameters. Conclusions : These results indicated that SKT + EKE could protect against oxidative stress-induced liver damage, and SKT + EKE is more effective than SKT alone or EKE alone.

• 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.

• Conservation Science in Museum
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• v.30
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• pp.71-88
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• 2023

This paper examined the visible characteristics and chemical composition of glass beads from the Joseon Dynasty as well as the associations thereof. It also explored the characteristics and uses of glass beads by region. This study covered a total of 1,819 pieces excavated from 25 locations in the Gyeonggi, Chungcheong, and Gyeongsang regions, of which 537 pieces were analyzed for their chemical composition. Glass beads of the Joseon Dynasty take a variety of shapes such as a Round, Coil, Floral, Segmented, Flat, Oval, and Calabash. Colors vary from shades of brown (brown, lemon yellow) and shades of blue (Bluish-Green, greenish-Blue, Purple-Blue) to shades of white (colorless, white) and shades of green (Green, Greenish-Blue, Greenish-Brown). Brown accounts for the largest percentage, followed by Bluish-Green, greenish-Blue. It was identified that Drawing technique was the most common glass bead production technique of the Joseon Dynasty. Potassium oxide (K₂O) was the most common flux agent for glass beads, while the potash glass and mixed alkali glass groups account for the largest quantity. The choice of stabilizers depended on the type of flux agents used, but the most common were calcium oxide (CaO) and aluminum oxide (Al₂O₃). The potash glass and potash lead glass groups are high in CaO and low in Al₂O₃, the mixed alkali glass group is high in CaO, and the lead glass group is low in CaO. In terms of the association between color and shape, most of the beads with shade of brown and blue have round shapes of brown and blue have spherical shapes, while the coil shape is prominent in blue beads. A high percentage of green and colorless beads also take the shape of a coil, while white beads in general have a floral shape. In terms of the association between shape and chemical composition, round, floral and segmented shapes account for a high percentage of the potash glass group, while coil and flat shapes are common in the mixed alkali glass group. This paper also analyzed the colorants for each color based on the association between color and chemical composition. Iron (Fe) was used as the colorant for brown and white, and titanium (Ti) and iron were used for light yellow. Purple-Blue was produced by by cobalt (Co), and greenish-Blue, Bluish-Green, green, Greenish-Blue were produced by iron and copper (Cu). Colorless beads had a generally low colorant content.