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61.
This paper presents an ontology-based holonic diagnostic system (OHDS) that combines the holonic paradigm with multi-agent system technology and ontology design, for the organization of unstructured biomedical research into structured disease information. We use ontologies as ‘brain’ for the holonic diagnostic system to enhance its ability to structure information in a meaningful way and share information fast. To integrate distributed heterogeneous knowledge available on the Web we use intelligent agents augmented by the mechanisms of the technology of fuzzy sets, which automatically structures the information in the adequate ontology template. Our vision of how this system implementation should be supported by a solid security shield that ensures the privacy and safety of medical information concludes the paper. 相似文献
62.
The buildup differential equations for the case of a single wire in high gradient magnetic filtration (HGMF)-axial configuration taking into account the suspension concentration are solved. A new equation for the deposit contour surface at different moments and for different suspension concentrations are obtained. The existence of a particulate suspension concentration, for which the radial extension velocity of deposit is maximum, is evidenced. The recovery for an ordered ferromagnetic matrix is calculated. The influence of the solid particle concentration from suspension on the filtration efficiency is presented 相似文献
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Oregon voters approved the first American statute authorizing physician-assisted suicide, the Oregon Death With Dignity Act, in 1994. The authors of this article identify some positive and negative psychological effects of laws such as Oregon's on patients. Generally, they conclude, on the basis of psychological theory and the available data, that laws such as Oregon's benefit patients psychologically. Undoubtedly, however, there exist important possible antitherapeutic effects on patients, and the authors hope that discussion of both therapeutic and antitherapeutic consequences will stimulate future research by social scientists in this area. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Anna Gliszczyńska-Świgło Alina Kałużewicz Katarzyna Lemańska Mikołaj Knaflewski Bożena Tyrakowska 《Food chemistry》2007,100(1):241-245
The effect of solar radiation on the quercetin and kaempferol contents in the inflorescence of three broccoli cultivars (‘Lord’, ‘Marathon’ and ‘Fiesta’) was investigated from 1999 to 2001. Great differences in the contents of both flavonols, dependent on growing time and cultivar, were found. Quercetin and kaempferol contents varied from 14.3 to 81.0 mg kg−1 f.w. and from 35.9 to 213 mg kg−1 f.w., respectively. Inflorescences of the cultivar ‘Lord’ were characterised by the highest mean content of quercetin and those of cultivar ‘Fiesta’ of kaempferol. The contents of both flavonols were highly positively correlated with total solar radiation in the period from planting to the harvest of broccoli inflorescences. 相似文献
66.
Deposition of trichlorosilanes with ester groups at their remote termini provides a convenient entry to carboxylic acid-bearing siloxane-anchored self-assembled monolayers. The de-esterification of these esters has been optimized to minimize monolayer damage, and their quantitative re-esterification provides clear evidence for the stability of these systems. Both the structure of the ester-terminated monolayer and its de-esterification/esterification chemistry can be easily monitored by FTIR-ATR measurements. This spectroscopic tool, together with a liquid cell that enables IR spectra to be measured in an aqueous environment, enables a detailed structural analysis of the carboxylic acid-bearing siloxane-anchored self-assembled monolayers and an assessment of their acid/base behavior (by in situ titration). The use of D2O instead of H2O for the in situ titration experiments also improves the available IR window. Both monomeric and dimeric/oligomeric acid groups are seen, and the relative ease of deprotonation of these various species can be directly monitored. Monomers of alkyl carboxylic acids that are hydrogen bonded only to surrounding water molecules have a pKa = 4.9, while the pKa for the aggregated molecules is 9.3. Similar behavior is seen for surface-bound benzoic acids, where the two pKa values are 4.7 and 9.0. The influence of temperature on these structures and their chemistry has been explored to a limited extent as well. When the alkylcarboxylic acid system is cooled to 10 °C, the pKa value for the acid monomers is reduced from 4.9 to 4.5 and increases from 9.3 to 10.3 for the aggregates. 相似文献
67.
The bulk polymerization reaction of N-vinylcarbazole (VK) at 70 °C in the presence of single-walled carbon nanotubes (SWNTs) leads to a new composite, whose optical properties were studied by photoluminescence (PL), surface enhanced Raman scattering (SERS) and Fourier transform infrared (FTIR) spectroscopies. A dramatic reduction of the poly(N-vinylcarbazole) (PVK) PL efficiency and a change in the vibrational structure of the PL spectrum of this polymer were observed by adding SWNTs to the synthesis mixture. Steric hindrance effects were evidenced both in SERS spectra of the VK when it interacts mechanico-chemically with SWNTs and in FTIR spectra of the un-doped PVK/SWNTs' composites. Cyclic voltammetry was used to demonstrate the doping process of PVK in PVK/SWNTs' composite. 相似文献
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Mihaela Nedelcu Mohammad S. M. Saifullah David G. Hasko Arang Jang David Anderson Wilhelm T. S. Huck Geraint A. C. Jones Mark E. Welland Dae Joon Kang Ullrich Steiner 《Advanced functional materials》2010,20(14):2317-2323
The fabrication of very narrow metal lines by the lift‐off technique, especially below sub‐10 nm, is challenging due to thinner resist requirements in order to achieve the lithographic resolution. At such small length scales, when the grain size becomes comparable with the line‐width, the built‐in stress in the metal film can cause a break to occur at a grain boundary. Moreover, the line‐width roughness (LWR) from the patterned resist can result in deposited metal lines with a very high LWR, leading to an adverse change in device characteristics. Here a new approach that is not based on the lift‐off technique but rather on low temperature hydrogen reduction of electron‐beam patterned metal naphthenates is demonstrated. This not only enables the fabrication of sub‐10 nm metal lines of good integrity, but also of low LWR, below the limit of 3.2 nm discussed in the International Technology Roadmap for Semiconductors. Using this method, sub‐10 nm nickel wires are obtained by reducing patterned nickel naphthenate lines in a hydrogen‐rich atmosphere at 500 °C for 1 h. The LWR (i.e., 3 σLWR) of these nickel nanolines was found to be 2.9 nm. The technique is general and is likely to be suitable for fabrication of nanostructures of most commonly used metals (and their alloys), such as iron, cobalt, nickel, copper, tungsten, molybdenum, and so on, from their respective metal–organic compounds. 相似文献