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Swati Mohan Rajiv Prakash 《Materials science & engineering. C, Materials for biological applications》2010,30(5):781-787
We report for the first time the functionalization of a conducting polymer with a metal complex in order to develop a new type of catalytic material exhibiting better electronic communication through their delocalized π electrons. The Co(II) complex having hydroxyl group as functional moiety is chemically coupled with carboxyl group of polyanthranilic acid which itself is a self doped conducting polymer. The covalent linkage between Co(II) and –OH group is confirmed using UV–vis, FT-IR and NMR spectroscopic techniques. The Co(II) complex functionalized polymer does exhibit excellent redox behavior and stability with mixed properties of Co(II) complex and π-conjugated polymer. The material possesses potential benefits in sensors/biosensor applications and it is demonstrated for the electroanalysis of ascorbic acid at a level of nano molar concentration. 相似文献
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Bimetallic clusters containing gold in conjunction with Group 8 metals have been intensively studied as it is proposed that these compounds may find uses as catalysts or materials (or as precursors to catalysts/materials). These types of compounds are very difficult to characterize by the mass spectrometric techniques traditionally used to analyse transition metal clusters. In this paper we report a derivatization method employing electrospray ionization mass spectrometry that is reliable and informative for these types of compounds. 相似文献
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Rajiv O. Dusane 《Thin solid films》2008,516(5):779-784
Today the Very Large Scale Industry (VLSI) is looking towards process solutions, which will avoid the problems associated with the conventional or presently employed technologies. This demand has become more intense with the VLSI industry extending their horizons towards Micro electro-mechanical systems (MEMS) based devices and Application-Specific Integrated Circuits ASICs). The areas of concern are development of high-k dielectric thin films, highly conducting polysilicon thin films, ultra thin diffusion barriers on low dielectric constant layers with electromigration resistant metal interconnects. Over the last few years, work carried out on the hot wire chemical vapor process (HWCVP) has shown that, this technique has great potential to yield the desired materials at low processing temperatures. This paper discusses the results we have obtained in the above areas and also the extension of application of this technique to areas like MEMS and ASICs. 相似文献
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This paper describes two new educational programs at Stanford that address some of the unique issues in teaching medical technology innovation and design. The first is a team‐based medical device design and prototyping course that is based on clinical immersion and “hands‐on” device prototyping. Medical device innovation at Stanford is further encouraged by means of a series of university‐wide competitions, called Invention Challenges, to invent solutions to defined clinical problems with the potential for real‐world impact. 相似文献
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Navita N. Lopez Rajiv Rangan Abbot F. Clark Tara Tovar-Vidales 《International journal of molecular sciences》2021,22(12)
Glaucoma is a group of optic neuropathies that leads to irreversible vision loss. The optic nerve head (ONH) is the site of initial optic nerve damage in glaucoma. ONH-derived lamina cribrosa (LC) cells synthesize extracellular matrix (ECM) proteins; however, these cells are adversely affected in glaucoma and cause detrimental changes to the ONH. LC cells respond to mechanical strain by increasing the profibrotic cytokine transforming growth factor-beta 2 (TGFβ2) and ECM proteins. Moreover, microRNAs (miRNAs or miR) regulate ECM gene expression in different fibrotic diseases, including glaucoma. A delicate homeostatic balance between profibrotic and anti-fibrotic miRNAs may contribute to the remodeling of ONH. This study aimed to determine whether modulation of miRNAs alters the expression of ECM in human LC cells. Primary human normal and glaucoma LC cells were grown to confluency and treated with or without TGFβ2 for 24 h. Differences in expression of miRNAs were analyzed using miRNA qPCR arrays. miRNA PCR arrays showed that the miR-29 family was significantly decreased in glaucomatous LC cell strains compared to age-matched controls. TGFβ2 treatment downregulated the expression of multiple miRNAs, including miR-29c-3p, compared to controls in LC cells. LC cells transfected with miR-29c-3p mimics or inhibitors modulated collagen expression. 相似文献
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Computational Markets to Regulate Mobile-Agent Systems 总被引:9,自引:0,他引:9
Bredin Jonathan Kotz David Rus Daniela Maheswaran Rajiv T. Imer Cagri Basar Tamer 《Autonomous Agents and Multi-Agent Systems》2003,6(3):235-263
Mobile-agent systems allow applications to distribute their resource consumption across the network. By prioritizing applications and publishing the cost of actions, it is possible for applications to achieve faster performance than in an environment where resources are evenly shared. We enforce the costs of actions through markets, where user applications bid for computation from host machines.We represent applications as collections of mobile agents and introduce a distributed mechanism for allocating general computational priority to mobile agents. We derive a bidding strategy for an agent that plans expenditures given a budget, and a series of tasks to complete. We also show that a unique Nash equilibrium exists between the agents under our allocation policy. We present simulation results to show that the use of our resource-allocation mechanism and expenditure-planning algorithm results in shorter mean job completion times compared to traditional mobile-agent resource allocation. We also observe that our resource-allocation policy adapts favorably to allocate overloaded resources to higher priority agents, and that agents are able to effectively plan expenditures, even when faced with network delay and job-size estimation error. 相似文献