• Transactions on Electrical and Electronic Materials
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• v.13 no.1
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• pp.43-46
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• 2012

Organic solar cell devices were fabricated using poly[9-(1-octylnonyl)-9H-carbazole-2.7-diyl]-2.5-thiophenediyl-2.1.3-benzothiadiazole-4.7-diyl-2.5-thiophenediyl] PCDTBT/ [6,6]-phenyl $C_{71}$ butyric acid methyl ester (PC71BM) active layer deposited by spin coating. Moreover, the relationship between solar cell performance and buffer layer thickness was investigated by spin coating speed and AFM imaging of the buffer layer surface. The performance of the organic solar cell with spin-coated active layer was then evaluated, and the power conversion efficiency of the solar cell was determined to be > 5%.

• Environmental Analysis Health and Toxicology
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• v.27
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• pp.11.1-11.8
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• 2012

Objectives: Hepatotoxicity of acetaminophen has been widely studied. However, the adverse effects on the heart have not been sufficiently evaluated. This study was performed to investigate cytotoxicity and alterations of gene expression in cultured cardiomyocytes ($H_9C_2$ cells) after exposure to acetaminophen. Methods: $H_9C_2$ cells were incubated in a 10 mM concentration of acetaminophen for the designated times (6, 12, and 24 hours), and cytotoxicity was determined by the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Alteration of gene expression was observed by microarray analysis, and RT-PCR was performed for the three representative oxidative stress-related genes at 24 hours after treatment. Results: It revealed that acetaminophen was toxic to cardiomyocytes, and numerous critical genes were affected. Induced genes included those associated with oxidative stress, DNA damage, and apoptosis. Repressed genes included those associated with cell proliferation, myocardial contraction, and cell shape control. Conclusions: These findings provide the evidences of acetaminophen-induced cytotoxicity and changes in gene expression in cultured cardiomyocytes of $H_9C_2$ cells.

• Journal of the Mineralogical Society of Korea
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• v.9 no.1
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• pp.35-42
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• 1996

Polycrystalline ZrH2 in tetragonal crystal system has been compressed in a modified Bassett-type diamond anvil cell up to 36.0 GPa at room temperature. X-ray diffraction data did not indicate any phase transitions at the present pressure range. The pressure dependence of the a-axis, c-axis, c/a and molar volume of ZrH2 was determined at pressures up to 36.0 GPa. Assuming the pressure derivative of the bulk modulus (K0') to be 4.11 from an ultrasonic value on Zr, bulk modulus (K0) was determined to be 160Gpa by fitting the pressure-volume data to the Birch-Murnaghan equation of state. Same sample was heated at $500^{\circ}C$ at the pressure of 9.8 GPa in a modified Sung-type diamond anvil cell. Unloaded and quenched sample revealed that the original tetragonal structure transforms into a hexagonal structured phase with a zero-pressure molar volume change of ~115.5%.

• Journal of Integrative Natural Science
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• v.9 no.2
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• pp.94-102
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• 2016

The crystal structure of the potential active 6-ethoxy-3-phenyl-5a,9a-dihydro-3H-chromen[4,3-c][1,2]oxazole-3a(4H)-carbonitrile ($C_{19}H_{15}N_2O_3$) has been determined from single crystal X-ray diffraction technique. The title compound crystallizes in the monoclinic space group C2/c with unit cell dimension a= 29.3026(9) ${\AA}$, b= 6.7695(2) ${\AA}$ and c= 19.7597(6) ${\AA}$ [${\alpha}= 90^{\circ}$, ${\beta}= 125.709(10)^{\circ}$ and ${\gamma}= 90^{\circ}$]. Single crystals suitable for X-ray diffraction were obtained by slow evaporation method, the isoxazole and six membered pyran rings adopts envelope conformation. The crystal packing of the molecules is stabilized by the weak $C-H{\ldots}N$ hydrogen bond interaction.

• Transactions on Electrical and Electronic Materials
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• v.9 no.2
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• pp.73-78
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• 2008

We investigated for comparison of large-area i-a-Si:H and p-a-SiC:H film quality like thickness uniformity, optical bandgap and surface roughness using both ICP-CVD and PECVD on the large-area substrate(diameter of 100 mm). As a whole, films using ICP-CVD could be achieved much uniform thickness and bandgap of that using PECVD. For i-a-Si:H films, its uniformity of thickness and optical bandgap were 2.8 % and 0.38 %, respectively. Also, thickness and optical bandgap of p-a-SiC:H films using ICP-CVD could be obtained at 1.8 % and 0.3 %, respectively. In case of surface roughness, average surface roughness (below 5 nm) of ICP-CVD film could be much better than that (below 30 nm) of PECVD film. HIT solar cell with 2 wt%-AZO/p-a-SiC:H/i-a-Si:H/c-Si/Ag structure was fabricated and characterized with diameter of 152.3 mm in this large-area ICP-CVD system. Conversion efficiency of 9.123 % was achieved with a practical area of $100\;mm\;{\times}\;100\;mm$, which can show the potential to fabrication of the large-area solar cell using ICP-CVD method.

• Polymer(Korea)
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• v.39 no.3
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• pp.412-417
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• 2015

A critical element in tissue engineering approaches is a control of the mechanical properties of polymer scaffolds to regulate cell phenotype, which may lead to clinically successful tissue regeneration. In this study, we hypothesized that gel stiffness could be a key factor to manipulate adhesion and proliferation of different types of cells. RGD-modified alginate gels with various mechanical properties were prepared and used as a substrate for MC3T3-E1 and H9C2 cells. Adhesion and growth rate of MC3T3-E1 cells in vitro were increased in parallel with an increase of gel stiffness. In contrast, those of H9C2 cells were decreased. This approach to control the mechanical properties of polymer scaffolds depending on the cell types may find useful applications in the tissue engineering.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.922-934
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• 2000

To investigate the composition of carotenoids present in marine organisms and the biological activity of the carotenoids, carotenoids of the muscles and tunic of tunicates and shellfishes were isolated and identified. Anitmutagenic activities of the carotenoids for S. typhimurium TA 98 and cytotoxic activity for cancer cell lines were determined. Total carotenoid contents in the muscle of tunicata ranged from 18.65 mg% to 2.39 mg%. The highest amount of the total carotenoid was found in the muscle of Halocynthia aurantium, followed by Styela clava (HERDMAN), H. roretzi, H. hilgendorfi f. igaboya, H. hilgendorfi f. retteri, S. plicata (LESUEUR) in order. Interestingly, total carotenoid content in the muscle of S. clava (HERDAMAN) was higher than that of H. roretzi. Total carotenoid content of all tunicata, other than H. aurantium and H. roretzi, were higher in muscle than tunic. The major carotenoids in H. roretzi, H. aurantium, S. plicata (LESUEUR), and S. clava (HERDAMAN) were cynthiaxanthin (25.1∼42.2%), halocynthiaxanthin (9.7∼26.3%), diatoxanthin (8.0∼18.7%) and β-carotene (7.7%∼21.7%). Similarly, cantaxanthin (19.6%), cynthiaxanthin (15.4%), halocynthiaxanthin (14.8%), and (3R, 3'R), (3S, 3'S)-astaxanthin (22.6%) in H. hilgendorfi f. retteri and fucoxanthin (26.6%), cynthiaxanthin (21.8%), halocynthiaxanthin (15.2%), and β-carotene (9.3%) in H. hilgendorfi f. igaboya were major carotenoids in both tunicate. However, the composition of carotenoids in muscle and tunic of tunicata was similar each other. Among the shellfishes examined, total carotenoid content of the muscle of Peronidia venulosa (Schrenck) and Corbicula fluminea, and of the gonad of Atrina pinnata and Chlamys farreri, was ranged from 2.51 to 6.83 mg% which were relatively higher than that of other shellfishes. The composition of the carotenoids of shellfishes, which might depend upon their living environments, was varied. But cynthiaxanthin (15.9∼39.0%) and zeaxanthin (9.6∼21.9%) in gonad of C. farreri, and muscles of Buccinum Volutharpa perryi (JAY) and Crassostrea gigas, cynthiaxanthin (21.5∼48.6%) and mytiloxanthin (14.6%) in muscle of C.fluminea and gonad of A. pinnata, and canthaxanthin (60.6%) and isozeaxanthin (20.5%) in muscles of P. venulosa (Schrenck), and β-carotene (23.7%∼37.8%) and zeaxanthin (18.2∼20.4) in muscles of Semisulcospira libertina and Meretrix lusoria were major carotenoids. Interestingly, diester type-carotenoids were present along with free type-carotenoids in muscles of C. gigas. antimutagenic effect of the carotenoids isolated from tunicata and shellfishes against 2-amino-3-methylimidazol [4,5-f]quinoline (IQ) for S. typhimurium TA 98 was proportional to the amount (20, 50 and 100㎍/plate) treated. Mutagenicity of IQ was significantly reduced by astaxanthin, isozeaxanthin, mytiloxanthin and halocynthiaxanthin, whereas the mutagenicity of aflatoxin B₁(AFB₁) was significantly reduced by β-carotene, isozeaxanthin, and mytiloxnthin. Growth inhibition effect of carotenoids isolated from tunicata and shellfishes for cancer cell was proportional to the amount (5, 10, and 20㎍/plate) treated. The growth of HeLa cell by β-carotene, cynthiaxanthin, astaxanthin and halocynthiaxanthin, NCI-H87 cell by β-carotene, astaxanthin, cynthiaxanthin, and halocynthiaxanthin, HT-29 cell by β-carotene, cynthiaxanthin, mytiloxanthin and halocynthiaxanthin, and MG-63 cells by β-carotene, cynthiaxanthin, astaxanthin, canthaxanthin and halocynthiaxanthin were statistically reduced.

• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.344-351
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• 1996

Microorganisms growing alcoholic distillery wastes were isolated from soil. Of them, the selected strain EL-9 had a capability of accumulating poly-$\beta$-hydroxybutyrate (PHB) when grown in alcoholic distillery wastes. The strain EL-9 was identified as a genus Actinobacillus based on the morphological, cultural, and biochemical characteristics. The strain EL-9 was named temporarily as Actino- bacillus sp. EL-9. The optimal temperature and pH for cell growth of Actinobacillus sp. EL-9 were 30$\circ$C and 7.0, respectively. The optimal medium compositions for cell growth comprised glucose 2%, NH$_{4}$NO$_{3}$ 0.15%, Na$_{2}$HP0$_{4}$-12H$_{2}$O 0.25%, KH$_{2}$PO$_{4}$ 0.25%, MgSO$_{4}$4-7H$_{2}$O 0.15%, FeSO$_{4}$-7H$_{2}$O 0.005%, CaCl$_{2}$-2H$_{2}$O 0.003% and trace element solution 5m/l. To investigate the optimal conditions for PHB production, two-stage culture technique was used. The result showed that the optimal conditions for PHB production are identical those for cell growth. When propionic acid was added as a cosubstrate, PHB/HV copolymer was produced.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.2
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• pp.173-183
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• 2020

An in vitro model for ischemia/reperfusion injury has not been well-established. We hypothesized that this failure may be caused by serum deprivation, the use of glutamine-containing media, and absence of acidosis. Cell viability of H9c2 cells was significantly decreased by serum deprivation. In this condition, reperfusion damage was not observed even after simulating severe ischemia. However, when cells were cultured under 10% dialyzed FBS, cell viability was less affected compared to cells cultured under serum deprivation and reperfusion damage was observed after hypoxia for 24 h. Reperfusion damage after glucose or glutamine deprivation under hypoxia was not significantly different from that after hypoxia only. However, with both glucose and glutamine deprivation, reperfusion damage was significantly increased. After hypoxia with lactic acidosis, reperfusion damage was comparable with that after hypoxia with glucose and glutamine deprivation. Although high-passage H9c2 cells were more resistant to reperfusion damage than low-passage cells, reperfusion damage was observed especially after hypoxia and acidosis with glucose and glutamine deprivation. Cell death induced by reperfusion after hypoxia with acidosis was not prevented by apoptosis, autophagy, or necroptosis inhibitors, but significantly decreased by ferrostatin-1, a ferroptosis inhibitor, and deferoxamine, an iron chelator. These data suggested that in our SIR model, cell death due to reperfusion injury is likely to occur via ferroptosis, which is related with ischemia/reperfusion-induced cell death in vivo. In conclusion, we established an optimal reperfusion injury model, in which ferroptotic cell death occurred by hypoxia and acidosis with or without glucose/glutamine deprivation under 10% dialyzed FBS.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.9
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• pp.808-811
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• 2008

Optical and mechanical properties of diamond-like carbon (DLC) films synthesized by RF plasma enhanced chemical vapor deposition were investigated as a function the C/H ratio in gas mixture. The C/H ratio was varied from 6 to 10 %, adjusting the amount of $CH_4$ and $H_2$ as the source gas. The optical and mechanical properties of DLC films were characterized by UV spectrometer, Ellipsometer and Nano-indenter. The change of the C/H ratio during synthesis of DLC films had many effects on the growth rate, transmittance, refractive index and hardness. The growth rate of the films increased exponentially with the increase in C/H ratio. The hardness of the films showed the tendency to improve with increasing C/H ratio, whereas the transmittance decreased. The refractive index was varied from 2.03 to 2.17, and these refractive indexes close to 2.0 indicates that it can be applied to Si-based solar cell.