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11.
This paper provides an overview of the Active XML project developed at INRIA over the past five years. Active XML (AXML, for short), is a declarative framework that harnesses Web services for distributed data management, and is put to work in a peer-to-peer architecture. The model is based on AXML documents, which are XML documents that may contain embedded calls to Web services, and on AXML services, which are Web services capable of exchanging AXML documents. An AXML peer is a repository of AXML documents that acts both as a client by invoking the embedded service calls, and as a server by providing AXML services, which are generally defined as queries or updates over the persistent AXML documents. The approach gracefully combines stored information with data defined in an intensional manner as well as dynamic information. This simple, rather classical idea leads to a number of technically challenging problems, both theoretical and practical. In this paper, we describe and motivate the AXML model and language, overview the research results obtained in the course of the project, and show how all the pieces come together in our implementation. The first and third authors were partially funded by the European Project Edos. Work done when the second and third authors were at INRIA. Work done when the second and third authors were at INRIA.  相似文献   
12.
High-purity, fine-grained oxide ceramic powders that are commonly used for ZnO-based varistors were synthesized by means of the reaction spray process. Processing steps included formation of the solutions of zinc nitrate and/or certain metal additives and spraying of the solution into a heated reaction column using a two-phase nozzle. After water evaporation from the droplets, the precursor salts were decomposed at elevated temperatures (up to 1473 K) in order to obtain homogeneous oxide powders with complex compositions corresponding to the final multicomponent varistor system. The decomposition behaviour of the precursors, as well as the characteristics of the resulting powders: crystallinity, phase composition, particle shape, morphology and particle-size distribution, were examined. It was shown that the characteristics of the reaction spray-derived powders can be controlled by adjusting the system and the solutions parameters.  相似文献   
13.
Multimedia Tools and Applications - The paper presents a method for denoising and reconstruction of sparse images based on a gradient-descent algorithm. It is assumed that the original (non-noisy)...  相似文献   
14.
Ultrathin superconductors of different materials are becoming a powerful platform to find mechanisms for enhancement of superconductivity, exploiting shape resonances in different superconducting properties. Here, we evaluate the superconducting gap and its spatial profile, the multiple gap components, and the chemical potential, of generic superconducting nanofilms, considering the pairing attraction and its energy scale as tunable parameters, from weak to strong coupling, at fixed electron density. Superconducting properties are evaluated at mean field level as a function of the thickness of the nanofilm, in order to characterize the shape resonances in the superconducting gap. We find that the most pronounced shape resonances are generated for weakly coupled superconductors, while approaching the strong coupling regime the shape resonances are rounded by a mixing of the subbands due to the large energy gaps extending over large energy scales. Finally, we find that the spatial profile, transverse to the nanofilm, of the superconducting gap acquires a flat behavior in the shape resonance region, indicating that a robust and uniform multigap superconducting state can arise at resonance.  相似文献   
15.
Information on the combined effect of dietary vitamin C and Se on the composition and oxidative stability of meat of broilers is not available in the literature. In the present experiment, male broiler chickens were fed a maize–wheat–soya diet supplemented with vitamin C at 280 and 560 mg/kg of diet, and Se (sodium selenite or selenised yeast; Se) at 0.3 mg/kg for 5 weeks. After slaughter, samples of thigh meat were analysed. The supplementation of diets with vitamin C or Se increased the protein concentration of the meat at the expense of fat. Vitamin C supplementation increased the vitamin C content of the meat in a dose-dependent manner and decreased the vitamin A concentration in the meat of broilers fed diets with sodium selenite or without a Se supplement. In the meat of the broilers that were fed these diets, the vitamin C decreased the lipid oxidation in meat that was stored for 5 days. No sparing effect of vitamin C was apparent on the amount of vitamin E in the meat. Selenised yeast was more effective in the enrichment of meat with Se than was selenite. Both Se sources increased the activity of glutathione peroxidase and the oxidative stability of the meat.  相似文献   
16.
We investigate how the interplay of quantum confinement and level broadening caused by disorder affects superconducting correlations in ultra-small metallic grains. We use the electron-phonon interaction-induced electron mass renormalization and the reduced static-path approximation of the BCS formalism to calculate the critical temperature as a function of the grain size. We show how the strong electron-impurity scattering additionally smears the peak structure in the electronic density of states of a metallic grain and imposes additional limits on the critical temperature under strong quantum confinement.  相似文献   
17.
Neural Computing and Applications - In the paper, the authors elaborate a recent research concerning the originality of artworks in terms of self-organization in the complex systems physics. It has...  相似文献   
18.
This study deals with the investigation of microphase‐separated morphology and phase behaviour in blends of polystyrene‐block‐polyisoprene with homopolystyrene and blends of polystyrene‐block‐poly(methyl methacrylate) with homopoly(methyl methacrylate) or homopolystyrene in the strong segregation regime using small‐angle X‐ray scattering and transmission electron microscopy as a function of composition, molecular weight of homopolymers, rM and temperature. Parameter rM = MH/MC (where MH is the molecular weight of homopolymer and MC that of the corresponding block copolymer) was selected to encompass behaviour of the chains denoted as a ‘wet brush’ (i.e. rM < 1). The relative domain spacing D/Do increases in the regime 0 < rM?1 with increasing concentration of homopolymer wP and increasing rM but depends on the specific implemented morphology. We tested a new approximate D/Do versus wP relation in the strong segregation regime using block copolymers of high molecular weights. It is shown that the parameters rM and χ3/2N determine the slope of the D/Do versus wP relation in the strong segregation regime and the new approximation generally matches the experimental data better than the approximations used so far. Copyright © 2010 Society of Chemical Industry  相似文献   
19.
20.
Mitragynine (MTR), the main indole alkaloid of the well-known plant kratom (Mitragyna speciosa), is one of the most studied natural products nowadays, due to its remarkable biological effects. It is a partial agonist on the opioid receptors, and as such relieves pain without the well-known side-effects of the opioids applied in the clinical practice. MTR and its derivatives therefore became novel candidates for drug development. The poor aqueous solubility and low bioavailability of drugs are often improved by cyclodextrins (CyDs) as excipients through host-guest type complex formation. Among the wide variety of CyDs, sulfobutylether-beta-cyclodextrin (SBEβCyD) is frequently used and official in the European and U.S. Pharmacopoeia. Herein, the host-guest complexation of MTR with βCyD and SBEβCyD was studied using chiroptical and NMR spectroscopy. It was found by NMR measurements that MTR forms a rather weak (logβ11 = 0.8) 1:1 host-guest complex with βCyD, while the co-existence of the 2MTR∙SBEβCyD and MTR∙SBEβCyD species was deducted from 1H NMR titrations in the millimolar MTR concentration range. Sulfobutylation of βCyD significantly enhanced the affinity towards MTR. The structure of the formed inclusion complex was extensively studied by circular dichroism spectroscopy and 2D ROESY NMR. The insertion of the indole moiety was confirmed by both techniques.  相似文献   
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