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941.
This paper deals with the use of Anderson heteropolyanions as alternative starting materials to the ammonium heptamolybdate and cobalt nitrate for the preparation of hydrotreatment oxidic precursors. Ammonium and cobalt salts of molybdocobaltate anions were synthesized and impregnated on alumina. The evolution of these compounds along the different steps of preparation of the oxidic precursors has been followed using various physical techniques such as Raman, XAS and UV–vis spectroscopies. It has been shown that the nature of the surface oxomolybdenum phase strongly depends on the nature of the starting salt. After sulfidation under H2/H2S, the performances of these new catalysts have been evaluated in hydrodesulfuration of thiophene. It appears that the cobalt salt of the decamolybdocobaltate anion [Co2Mo10O38H4]6−, with a Co/Mo ratio equal to 0.5, allows us to improve the catalytic conversion by comparison to reference catalysts prepared with ammonium heptamolybdate and cobalt nitrate as starting materials. It has been shown that this improvement is due to the preservation of the heteropolyanionic structure up to the drying step.  相似文献   
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944.
A new CAD mesh segmentation method, based on curvature tensor analysis   总被引:5,自引:0,他引:5  
This paper presents a new and efficient algorithm for the decomposition of 3D arbitrary triangle meshes and particularly optimized triangulated CAD meshes. The algorithm is based on the curvature tensor field analysis and presents two distinct complementary steps: a region based segmentation, which is an improvement of that presented by Lavoue et al. [Lavoue G, Dupont F, Baskurt A. Constant curvature region decomposition of 3D-meshes by a mixed approach vertex-triangle, J WSCG 2004;12(2):245-52] and which decomposes the object into near constant curvature patches, and a boundary rectification based on curvature tensor directions, which corrects boundaries by suppressing their artefacts or discontinuities. Experiments conducted on various models including both CAD and natural objects, show satisfactory results. Resulting segmented patches, by virtue of their properties (homogeneous curvature, clean boundaries) are particularly adapted to computer graphics tasks like parametric or subdivision surface fitting in an adaptive compression objective.  相似文献   
945.
IT outsourcing research has often been at the transaction level, focusing on the role of the characteristics of the IT activities as the antecedents of outsourcing decisions. The present study extends past research efforts examining the relationships between organizational level variables—in particular the business strategy—and the decision to outsource. Results show that prospectors and analyzers are more aggressive in their use of outsourcing for IT operations. However, no differences between the behaviour of the different strategic groups were found for maintenance activities, suggesting that these activities are too far from the core of the organization to be influenced by strategic profile.
Suzanne RivardEmail:
  相似文献   
946.
SweetWiki: A semantic wiki   总被引:1,自引:0,他引:1  
Everyone agrees that user interactions and social networks are among the cornerstones of “Web 2.0”. Web 2.0 applications generally run in a web browser, propose dynamic content with rich user interfaces, offer means to easily add or edit content of the web site they belong to and present social network aspects. Well-known applications that have helped spread Web 2.0 are blogs, wikis, and image/video sharing sites; they have dramatically increased sharing and participation among web users. It is possible to build knowledge using tools that can help analyze users’ behavior behind the scenes: what they do, what they know, what they want. Tools that help share this knowledge across a network, and that can reason on that knowledge, will lead to users who can better use the knowledge available, i.e., to smarter users. Wikipedia, a wildly successful example of web technology, has helped knowledge-sharing between people by letting individuals freely create and modify its content. But Wikipedia is designed for people—today's software cannot understand and reason on Wikipedia's content. In parallel, the “semantic web”, a set of technologies that help knowledge-sharing across the web between different applications, is starting to gain attraction. Researchers have only recently started working on the concept of a “semantic wiki”, mixing the advantages of the wiki and the technologies of the semantic web. In this paper we will present a state-of-the-art of semantic wikis, and we will introduce SweetWiki, an example of an application reconciling two trends of the future web: a semantically augmented web and a web of social applications where every user is an active provider as well as a consumer of information. SweetWiki makes heavy use of semantic web concepts and languages, and demonstrates how the use of such paradigms can improve navigation, search, and usability.  相似文献   
947.
Dr. Gilles Ouvry  Dr. Nicolas Atrux‐Tallau  Dr. Franck Bihl  Aline Bondu  Dr. Claire Bouix‐Peter  Isabelle Carlavan  Olivier Christin  Marie‐Josée Cuadrado  Dr. Claire Defoin‐Platel  Dr. Sophie Deret  Denis Duvert  Christophe Feret  Mathieu Forissier  Dr. Jean‐François Fournier  David Froude  Dr. Fériel Hacini‐Rachinel  Dr. Craig Steven Harris  Dr. Catherine Hervouet  Dr. Hélène Huguet  Guillaume Lafitte  Dr. Anne‐Pascale Luzy  Dr. Branislav Musicki  Danielle Orfila  Benjamin Ozello  Coralie Pascau  Jonathan Pascau  Véronique Parnet  Guillaume Peluchon  Romain Pierre  Dr. David Piwnica  Dr. Catherine Raffin  Patricia Rossio  Delphine Spiesse  Dr. Nathalie Taquet  Dr. Etienne Thoreau  Rodolphe Vatinel  Dr. Emmanuel Vial  Dr. Laurent François Hennequin 《ChemMedChem》2018,13(4):321-337
With possible implications in multiple autoimmune diseases, the retinoic acid receptor‐related orphan receptor RORγ has become a sought‐after target in the pharmaceutical industry. Herein are described the efforts to identify a potent RORγ inverse agonist compatible with topical application for the treatment of skin diseases. These efforts culminated in the discovery of N‐(2,4‐dimethylphenyl)‐N‐isobutyl‐2‐oxo‐1‐[(tetrahydro‐2H‐pyran‐4‐yl)methyl]‐2,3‐dihydro‐1H‐benzo[d]imidazole‐5‐sulfonamide (CD12681), a potent inverse agonist with in vivo activity in an IL‐23‐induced mouse skin inflammation model.  相似文献   
948.
Erythropoietin‐producing hepatocellular (EPH) receptors are transmembrane receptor tyrosine kinases. Their extracellular domains bind specifically to ephrin A/B ligands, and this binding modulates intracellular kinase activity. EPHs are key players in bidirectional intercellular signaling, controlling cell morphology, adhesion, and migration. They are increasingly recognized as cancer drug targets. We analyzed the binding of NVP‐BHG712 (NVP) to EPHA2 and EPHB4. Unexpectedly, all tested commercially available NVP samples turned out to be a regioisomer (NVPiso) of the inhibitor, initially described in a Novartis patent application. They only differ by the localization of a single methyl group on either one of two adjacent nitrogen atoms. The two compounds of identical mass revealed different binding modes. Furthermore, both in vitro and in vivo experiments showed that the isomers differ in their kinase affinity and selectivity.  相似文献   
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Persons with chronic mental illnesses have a higher prevalence of medical illnesses and higher mortality rates than the general population. Those living in the community are usually linked with mental health services but are expected to manage their own medical care. The ability to manage their health care and the ability of "surrogate families" to assist them were measured among residents and staff of supervised community residences. In its surrogate role, the agency promoted routine health examinations and follow-up care. Its staff was a central resource for the residents, who sought out staff members for assistance with their health problems. However, residents and staff alike lack knowledge about health problems, medications, and approaches to modifying unhealthy lifestyle practices. Although residents identified lack of knowledge about sexually transmitted diseases as a major concern, staff indicated discomfort with this topic. These findings suggest the importance of supporting chronically mentally ill persons and residential staff in managing residents' health care functions.  相似文献   
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