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51.
52.
There is growing interest in the role and contribution of e-government to the levels of corruption, economic prosperity and environmental degradation of nation states. In this paper, we use publicly available archival data to explore the relationships among them. Results substantiate a significant relationship between (1) e-government maturity and corruption; and (2) e-government maturity, economic prosperity and environmental degradation through the mediating effects of corruption. The findings suggest that while e-government maturity did not contribute to economic prosperity and environmental degradation, its value could be realized indirectly via its impacts on corruption. Our findings contribute to the theoretical discourse on e-government impact by identifying the role of e-government in a country and provide indications to practice on enhancing its economic prosperity and lowering its environmental degradation by managing the levels of e-government maturity and corruption.  相似文献   
53.
Biomaterials with dynamically tunable properties are critical for a range of applications in regenerative medicine and basic biology. In this work, we show the reversible control of gelatin methacrylate (GelMA) hydrogel stiffness through the use of DNA crosslinkers. We replaced some of the inter-GelMA crosslinks with double-stranded DNA, allowing for their removal through toehold-mediated strand displacement. The crosslinks could be restored by adding fresh dsDNA with complementary handles to those on the hydrogel. The elastic modulus (G’) of the hydrogels could be tuned between 500 and 1000 Pa, reversibly, over two cycles without degradation of performance. By functionalizing the gels with a second DNA strand, it was possible to control the crosslink density and a model ligand in an orthogonal fashion with two different displacement strands. Our results demonstrate the potential for DNA to reversibly control both stiffness and ligand presentation in a protein-based hydrogel, and will be useful for teasing apart the spatiotemporal behavior of encapsulated cells.  相似文献   
54.
Protection of Metals and Physical Chemistry of Surfaces - Dense alumina coatings were fabricated over aluminum alloy via dip coating method using oxime-modified aluminum(III) isopropoxide as a...  相似文献   
55.
Presently, fly ash–water slurry is transported to ash disposal site at very low solid concentration of approximately 15–20% (by weight), resulting in huge water and energy wastage which leads to several environmental and health problem. The production of a large amount of the toxic metal elements in the ash disposal system of the thermal power plants can pose negative environmental effects on human health and on plants. In the present study, an attempt has been made to investigate the leaching characteristics of fly ash at higher concentrations. The bottom ash was taken as an additive in the proportion of 10, 20, and 30% (by weight) to enhance the leaching characteristics of fly ash. The solid concentration of fly ash suspension was taken in the range of 40 to 60% (by weight). The addition of additive helps to reduce the tracing metal concentration of fly ash. Leaching experiment data show that leachate concentration of all tracing elements present in fly ash reduced maximum with 20% addition of bottom ash (by weight). The present study helps to improve the ash disposal system of the thermal power plant and to minimize the environmental impact.  相似文献   
56.
Multimedia Tools and Applications - Leap motion sensor provides a new way of interaction with computers or mobile devices. With this sensor, users can write in air by moving palm or finger, thus,...  相似文献   
57.
We synthesized a family of neuromuscular blocking agents (NMB) based on decamethonium, but containing a carborane cluster in the methylene chain between the two quaternary ammonium groups. The carborane cluster isomers o-NMB, m-NMB, and p-NMB were tested in animals for neuromuscular block and compared with agents used clinically: rocuronium and decamethonium. All three isomers caused reversible muscle weakness in mice as determined by grip strength and inverted screen tests, with a potency rank of p-NMB > rocuronium > decamethonium > m-NMB > o-NMB. The mechanism of action of the compounds was determined by using the in vitro rat phrenic nerve hemi-diaphragm preparation and electrophysiologic measurements in cells. Neostigmine reversed hemi-diaphragm weakness caused by the three isomers and rocuronium, but not succinylcholine. In electrophysiologic recordings of currents through acetylcholine receptor channels, the carborane compounds did not activate channel activity but did inhibit channel activation by acetylcholine. These results demonstrate that the carborane neuromuscular blocking agents are non-depolarizers in contrast to the depolarizing action of the parent compound.  相似文献   
58.
Journal of Materials Science: Materials in Electronics - The bisthiourea copper and cadmium adipate (BTCu/CdA), and their glycine-doped derivatives (BTCu/CdA-Gly) have been synthesized by simple...  相似文献   
59.
Biopolymer based composites have been employed in numerous applications with increasing interest not only due to renewable, eco-friendly nature, but also because of the flexibility in processing conditions and competitive cost of their end products. The conductive materials from biopolymers have been found applicable in robots, medical imaging, sensitive membranes, actuators, visual displays, electronic wiring and shielding, and components in batteries. Cellulose is one of the most abundant biopolymers in the nature, which has received special attention for development of conducting materials due to biocompatibility for protein and drug immobilization and ability to form the composites with synthetic polymers. The present review is aimed to provide concisely the current status in this field of conducting composites from cellulose, with brief discussions of associated problems and future applications.  相似文献   
60.
Thermo-electrochemical cells (or thermocells) convert thermal energy to electricity in continuous operation based on a balance of ion conduction and redox reactions at hot and cold electrodes. In this study, the fundamental governing equations for mass and heat transfer, fluid dynamics, and electrokinetics in thermocells are presented and solved numerically using COMSOL. A parametric study is performed to explore the limitations and optimal cell dimensions for maximum energy conversion efficiency in thermocells. Series-stacking designs are demonstrated to have the potential to increase conversion efficiency by 100 % compared to a single cell configuration. Natural convection is shown to significantly increase the conversion efficiency of thermocells with conventional aqueous electrolyte (0.4 M potassium ferri/ferrocyanide), by compressing the diffusive boundary layers. A flow cell thermocell design is also considered. Results reveal that the ohmic resistance of the electrolyte limits the energy conversion efficiency of this design.  相似文献   
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