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81.
In biomedical informatics, ontologies are considered a key technology for annotating, retrieving and sharing the huge volume of publicly available data. Due to the increasing amount, complexity and variety of existing biomedical ontologies, choosing the ones to be used in a semantic annotation problem or to design a specific application is a difficult task. As a consequence, the design of approaches and tools addressed to facilitate the selection of biomedical ontologies is becoming a priority. In this paper we present BiOSS, a novel system for the selection of biomedical ontologies. BiOSS evaluates the adequacy of an ontology to a given domain according to three different criteria: (1) the extent to which the ontology covers the domain; (2) the semantic richness of the ontology in the domain; (3) the popularity of the ontology in the biomedical community. BiOSS has been applied to 5 representative problems of ontology selection. It also has been compared to existing methods and tools. Results are promising and show the usefulness of BiOSS to solve real-world ontology selection problems. BiOSS is openly available both as a web tool and a web service.  相似文献   
82.
Clinical practice guidelines in paper format are still the preferred form of delivery of medical knowledge and recommendations to healthcare professionals. Their current support and development process have well identified limitations to which the healthcare community has been continuously searching solutions. Artificial intelligence may create the conditions and provide the tools to address many, if not all, of these limitations.. This paper presents a comprehensive and up to date review of computer-interpretable guideline approaches, namely Arden Syntax, GLIF, PROforma, Asbru, GLARE and SAGE. It also provides an assessment of how well these approaches respond to the challenges posed by paper-based guidelines and addresses topics of Artificial intelligence that could provide a solution to the shortcomings of clinical guidelines. Among the topics addressed by this paper are expert systems, case-based reasoning, medical ontologies and reasoning under uncertainty, with a special focus on methodologies for assessing quality of information when managing incomplete information. Finally, an analysis is made of the fundamental requirements of a guideline model and the importance that standard terminologies and models for clinical data have in the semantic and syntactic interoperability between a guideline execution engine and the software tools used in clinical settings. It is also proposed a line of research that includes the development of an ontology for clinical practice guidelines and a decision model for a guideline-based expert system that manages non-compliance with clinical guidelines and uncertainty.  相似文献   
83.
Acrylic acid is a refractory compound for the non-catalytic wet oxidation (WO) process and can seriously damage the environment when released in industrial effluents. Oxidation of acrylic acid by catalytic wet oxidation (CWO) was studied in slurry conditions in a high-pressure batch reactor at 200 °C and 15 bar of oxygen partial pressure. Several solid cerium-based catalysts prepared in our laboratory were used (Ag/Ce, Co/Ce, Mn/Ce, CeO, MnO) and evaluated in terms of activity, selectivity and stability. Mn/Ce shows the higher activity in 2 h with 97.7% reduction of total organic carbon (TOC) followed by: MnO(95.5%)>Ag/Ce(85.0%)>Co/Ce(65.1%)>CeO(61.2%). Attempts were also carried out to analyze the influence of different Mn/Ce molar ratios. High percentages of Mn lead to practically total organic carbon concentration (TOC) abatements while low ratios lead to the formation of non-oxidizable compounds. Acrylic acid was readily degraded by all the catalysts pointing out the high importance of using a catalytic process. pH was an indicator of the reaction pathway and acetic acid was found as the major reaction intermediate compound; however it is completely oxidized after 2 h with exception for Co/Ce, CeO and MnO. Carbon adsorption and leaching of metals were poorly found for Mn/Ce indicating high stability. The catalyst microstructure after the reaction was analyzed and formation of whiskers of β-MnO2 (or less probably MnOOH) were observed at the catalyst surface. Therefore, Mn/Ce revealed to be a promising catalyst for the treatment of effluents containing acrylic acid; nevertheless, its commercialization depends on further research.  相似文献   
84.
85.
This study examines in detail the influence of low‐temperature plasma and biopolymer chitosan treatments on wool dyeability. Wool knitted fabrics were treated and characterized by whiteness and shrink‐resistance measurements. Surface modification was assessed by contact‐angle measurements of human hair fibers, which were used as a model to study the wetting properties of the treated wool knitted fabrics. The dyeing behavior was assessed from the diffusion mechanism point of view. The dyeing kinetics were measured at two different pHs (4.2 and 6.5) and three different temperatures (60, 85, and 100°C) to gain information about the contribution of the surface modification treatment to the dyeing mechanism. The exhaustion and reflectance data were compared, and the apparent diffusion coefficients were calculated. On the basis of the obtained results, a model for the dyeing mechanism of the chitosan treated wool was proposed. When treated with chitosan, the polymer sheath spread on the surface of the fibers acted as a predominant dyeing site in very short dyeing times, thus interacting with the dye and in later stages imparting the dye to the wool fiber. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2204–2214, 2005  相似文献   
86.
The alignment of information systems with the business goals of an organisation, although a topic of great importance, is not always properly valued or taken into consideration. In general, managers have different opinions to chief information officers (CIOs) in relation to IS, especially with regard to their importance and value to the business and also in terms of investment needs. Here, we discuss and study new approaches to methods and tools for assessing the relative importance of each information system to business, focusing on the financial sector including banks and insurance companies. We suggest the introduction of new key indicators for better decision support and to identify investment priorities, and present results regarding the relative importance of each process to support the business strategy. The primary goal for the inherent research project is to analyse the main problems and difficulties encountered by IS and IT managers, featuring different players and how they relate. The main contributions of this work are the CRUDi framework as a tool to improve alignment between business and IS strategies and the CRUDi survey and its results qualifying the financial sector's opinion regarding the relative importance of processes and investments.  相似文献   
87.
The effects of the SAR (14 and 38) and of the methodology of introduction of nickel (wetness impregnation and ion exchange) on catalyst activation were investigated in Ni/USY model catalysts submitted to two activation treatments: reduction (A) and reduction/calcination/reduction, successively (B). the catalysts prepared by wetness impregnation, a marked increase in the catalytic activity after treatment B was observed. On the basis of the catalyst efficiency toward ethane hydrogenolysis, the lower SAR catalyst presents a threefold higher activity. On the contrary, the catalysts prepared by ion exchange, as well as a model catalyst prepared by wetness impregnation over a USY exhaustively exchanged with nickel ions, do not present measurable increasing of the catalytic activity under the same activation conditions. Monitoring the catalyst activation by EXAFS indicates the formation of nickel clusters in the impregnated catalysts after activation treatment B, which should be responsible for the high catalytic activity. However, TEM images reveal a bimodal particle size distribution, with large (ca. 20 nm) and small nickel particles. Temperature-programmed reduction performed under the same conditions of catalyst activation suggests that only the small nickel particles are activated under the experimental conditions adopted in this work.  相似文献   
88.
A commercial perfluoropolyether containing alkoxysilane functionalities was employed to prepare organic–inorganic hybrid coatings by using the sol‐gel process in the presence of tetraethoxysilane. Contact angle analysis revealed a strong hydrophobic and oleophobic character of the coatings almost independently from the molecular weight of the starting fluorinated oligomer. Surface tension values were in the range of 14–16 mN/m, suggesting a preferential segregation of fluorinated segments onto the surface of the coating. Atomic force microscopy showed the presence very smooth surfaces permitting to neglect the contribution of the surface roughness to wettability. Friction coefficient values were markedly lower with respect to the value of uncoated glass substrate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1483–1488, 2006  相似文献   
89.
The conditions for obtaining recrystallization in more ordered modifications are described for an uniaxially oriented sample of isotactic polypropylene, annealed with fixed ends. These recrystallization conditions are related to the conditions of a lamination process.  相似文献   
90.
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