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251.
Context-aware platform for mobile data management   总被引:1,自引:0,他引:1  
Interaction design is a major issue for mobile information systems in terms of not only the choice of input/output channels and presentation of information, but also the application of context-awareness. To support experimentation with these factors, we have developed platforms to support the rapid prototyping of multi-channel, multi-modal, context-aware applications. The Java-based platform presented here is based on an integration of a cross-media link server and an object-oriented framework for advanced content publishing, along with a Client Controller and Context Engine. We also describe how this platform was used to develop a mobile tourist information system for an international arts festival where interaction was based on a combination of interactive paper and speech output. Moira C. Norrie is a Professor at ETH Zurich where she is head of the Institute for Information Systems and leads the Global Information Systems research group. Her research interests include object-oriented models and systems for data management, web engineering, mobile and personal information systems and interactive paper as a medium for integrating printed and digital information. Beat Signer is a Post-Doctoral researcher in the Global Information Systems research group at ETH Zurich. He received a Ph.D. from ETH Zurich in 2005 for his work investigating fundamental concepts for interactive paper and cross-media information management. His research interests include interactive paper, cross-media information management, object-oriented technologies and software engineering. Michael Grossniklaus is a research assistant in the Global Information Systems research group at ETH Zurich. He received a Diploma (M.Sc.) in Computer Science from ETH Zurich in 2001 and is currently completing his Ph.D. His main research interest is empowering information systems for context-aware data management and delivery in the domain of web engineering and mobile computing. Rudi Belotti was a research assistant in the Global Information Systems research group at ETH Zurich from 2004–2006. He received a Diploma (M.Sc.) in Computer Science from ETH Zurich in 2004. In his research, he developed a general model and engine for the management of context information in mobile information systems. He is currently working for an e-business services company in Ticino, Switzerland. Corsin Decurtins is a research assistant in the Global Information Systems research group at ETH Zurich. He received a Diploma (M.Sc.) in Computer Science from ETH Zurich in 2002. His research focusses on model-based approaches and infrastructure for ubiquitous and mobile information environments. In addition to his Ph.D. Corsin also works part-time as a senior software engineer at the software company Netcetera. Nadir Weibel is a research assistant in the Global Information Systems research group at ETH Zurich. He received a Diploma (M.Sc.) in Computer Science from ETH Zurich in 2003 and is currently working on his Ph.D. His research is in the area of interactive paper, particularly on the authoring and publishing infrastructure for interactive documents as well as issues of human computer interaction and mobile environments.  相似文献   
252.
Protein–nucleic acid interactions play important roles not only in energy-providing reactions, such as ATP hydrolysis, but also in reading, extending, packaging, or repairing genomes. Although they can often be analyzed in detail with X-ray crystallography, complementary methods are needed to visualize them in complexes, which are not crystalline. Here, we show how solid-state NMR spectroscopy can detect and classify protein–nucleic interactions through site-specific 1H- and 31P-detected spectroscopic methods. The sensitivity of 1H chemical-shift values on noncovalent interactions involved in these molecular recognition processes is exploited allowing us to probe directly the chemical bonding state, an information, which is not directly accessible from an X-ray structure. We show that these methods can characterize interactions in easy-to-prepare sediments of the 708 kDa dodecameric DnaB helicase in complex with ADP:AlF4:DNA, and this despite the very challenging size of the complex.  相似文献   
253.
Chemical properties of ethylene oxide (EO) and propylene oxide (PO) block copolymers are strongly dependent on their sequence. Useful information about copolymer sequence can be obtained by tandem mass spectrometry (MS/MS). In this work, collision-induced dissociation (CID) of ammonium adducts of various linear triblock and glycerol derivative diblock copolyethers produced by electrospray ionization was studied under low-energy conditions. At first, homopolymers MS/MS spectra enabled us to identify the nature of the product ions and to suggest decomposition pathways. Then, it was shown that copolyethers with the same composition in each repeat unit but with inversed block sequences (i.e., PEO-b-PPO-b-PEO vs PPO-b-PEO-b-PPO and gPEO-b-PPO vs gPPO-b-PEO) can be easily distinguished with characteristic fragment ions. In the case of linear copolymers, CID spectra gave pertinent information about block lengths.  相似文献   
254.
目前,城市化正在全世界范围内高速发展,尤其以亚洲各发展中国家更为突出。从近来新闻报道反映前景暗淡的大城市的图片中,可以看到由于政府行政管理的不善,过度的土地投机和粗糙的规划设计,已造成人类日常生活中自然和社会环境的不断恶化。对亚洲各国来说当前的经济繁...  相似文献   
255.
Newborn neurons in the adult hippocampus are regulated by many intrinsic and extrinsic cues. It is well accepted that elevated glucocorticoid levels lead to downregulation of adult neurogenesis, which this review discusses as one reason why psychiatric diseases, such as major depression, develop after long-term stress exposure. In reverse, adult neurogenesis has been suggested to protect against stress-induced major depression, and hence, could serve as a resilience mechanism. In this review, we will summarize current knowledge about the functional relation of adult neurogenesis and stress in health and disease. A special focus will lie on the mechanisms underlying the cascades of events from prolonged high glucocorticoid concentrations to reduced numbers of newborn neurons. In addition to neurotransmitter and neurotrophic factor dysregulation, these mechanisms include immunomodulatory pathways, as well as microbiota changes influencing the gut-brain axis. Finally, we discuss recent findings delineating the role of adult neurogenesis in stress resilience.  相似文献   
256.
Abgottspon D  Ernst B 《Chimia》2012,66(4):166-169
The discovery of antimicrobials as β-lactam antibiotics or aminoglycosides revolutionized the treatment of infectious diseases. However, the extensive use rapidly created the problem of resistant pathogens, which are increasingly difficult to treat. FimH antagonists are a new class of antimicrobials, which target the bacterial adhesion to urothelial cells, a crucial first step in the establishment of urinary tract infections. Because of their different mode of action, FimH antagonists neither kill nor inhibit the growth of bacteria, they should have a reduced potential to generate resistant strains. This mini-review outlines the main problems associated with increasing development of antimicrobial resistance. Furthermore, it summarizes the currently available in vivo studies in mice for the treatment of urinary tract infections conducted with FimH antagonists.  相似文献   
257.
The ion conductivity of two series of porous ceramic diaphragms impregnated with caustic potash was investigated by electrochemical impedance spectroscopy. To understand the impact of the pore structure on ion conductivity, the three‐dimensional (3‐D) pore geometry of the diaphragms was characterized with synchrotron x‐ray absorption tomography. Ion migration was calculated based on an extended pore structure model, which includes the electrolyte conductivity and geometric pore parameters, for example, tortuosity (τ) and constriction factor (β), but no fitting parameters. The calculated ion conductivities are in agreement with the data obtained from electrochemical measurements on the diaphragms. The geometric tortuosity was found to be nearly independent of porosity. Pore path constrictions diminish with increasing porosity. The lower constrictivity provides more pore space that can effectively be used for mass transport. Direct measurements from tomographs of tortuosity and constrictivity opens new possibilities to study pore structures and transport properties of porous materials.  相似文献   
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