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601.
On‐Fabrication Solid‐State N‐Doping of Graphene by an Electron‐Transporting Metal Oxide Layer for Efficient Inverted Organic Solar Cells
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602.
Yuree Byun Young-Chul Choi Yongsu Jeong Jaeseung Yoon Kwanghee Baek 《Molecules and cells》2020,43(12):975
Hypoxia plays important roles in cancer progression by inducing angiogenesis, metastasis, and drug resistance. However, the effects of hypoxia on long noncoding RNA (lncRNA) expression have not been clarified. Herein, we evaluated alterations in lncRNA expression in lung cancer cells under hypoxic conditions using lncRNA microarray analyses. Among 40,173 lncRNAs, 211 and 113 lncRNAs were up- and downregulated, respectively, in both A549 and NCI-H460 cells. Uroplakin 1A (UPK1A) and UPK1A-antisense RNA 1 (AS1), which showed the highest upregulation under hypoxic conditions, were selected to investigate the effects of UPK1A-AS1 on the expression of UPK1A and the mechanisms of hypoxia-inducible expression. Following transfection of cells with small interfering RNA (siRNA) targeting hypoxia-inducible factor 1α (HIF-1α), the hypoxia-induced expression of UPK1A and UPK1A-AS1 was significantly reduced, indicating that HIF-1α played important roles in the hypoxia-induced expression of these targets. After transfection of cells with UPK1A siRNA, UPK1A and UPK1A-AS1 levels were reduced. Moreover, transfection of cells with UPK1A-AS1 siRNA downregulated both UPK1A-AS1 and UPK1A. RNase protection assays demonstrated that UPK1A and UPK1A-AS1 formed a duplex; thus, transfection with UPK1A-AS1 siRNA decreased the RNA stability of UPK1A. Overall, these results indicated that UPK1A and UPK1A-AS1 expression increased under hypoxic conditions in a HIF-1α-dependent manner and that formation of a UPK1A/UPK1A-AS1 duplex affected RNA stability, enabling each molecule to regulate the expression of the other. 相似文献
603.
In this work, we first present a method to experimentally capture the free flight of a beetle (Allomyrina dichotoma), which is not an active flyer. The beetle is suspended in the air by a hanger to induce the free flight. This flight is filmed using two high-speed cameras. The high speed images are then examined to obtain flapping angle, flapping frequency, and wing rotation of the hind wing. The acquired data of beetle free flight are used to design a motor-driven flapper that can approximately mimic the beetle in terms of size, flapping frequency and wing kinematics. The flapper can create a large flapping angle over 140° with a large passive wing rotation angle. Even though the flapping frequency of the flapper is not high enough compared to that of a real beetle due to the limited motor torque, the flapper could produce positive average vertical force. This work will provide important experience for future development of a beetle-mimicking Flapping-Wing Micro Air Vehicle (FWMAV). 相似文献
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607.
Hee-Guk Byun Tae-Kil Eom Won-Kyo Jung Se-Kwon Kim 《Biotechnology and Bioprocess Engineering》2007,12(5):484-490
In this study, fish oil was hydrolyzed by lipase in a fish oil-in-water emulsion system in an effort to improve the functional
properties of fish oil. Lipase activity was found to depend on the quality of the water/fish oil interface area. We selected
several suitable emulsifiers, and their emulsifying activities were evaluated under a variety of conditions, including concentration,
water-oil ratios, pH values, and temperature. Among the selected emulsifiers, the emulsifying activity of gelatin was higher
than those of carboxymethyl chitin (CM-chitin), bovine serum albumin, and Tween-20, all of which are commercial emulsificers
Moreover, the emulsifying activity of the gelatin solution was the highest at 0.5%, and was reduced with increasing concentrations
of above 1%. The optimal water-oil ratio, pH, and temperature conditions were 40% (w/v), pH 8.0 and 40°C, respectively. Under
these conditions, the emulsifying activity of gelatin solution was 86%. The emulsion structure of the gelatin solution was
characterized by high density and small particle size. The degree of sardine oil hydrolysis in the emulsion system was 50%
higher than that of the non-emulsion system. The lipid species of the lipase-prepared sardine oil hydrolysates were identified
as triacylglycerol, 1,3- and 1,2-diacylglycerol, monoacylglycerol, and fatty acid. 相似文献
608.
Organic Solar Cells: On‐Fabrication Solid‐State N‐Doping of Graphene by an Electron‐Transporting Metal Oxide Layer for Efficient Inverted Organic Solar Cells (Adv. Energy Mater. 12/2016)
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