62 research outputs found

    Continuous Improvement Through Knowledge-Guided Analysis in Experience Feedback

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    Continuous improvement in industrial processes is increasingly a key element of competitiveness for industrial systems. The management of experience feedback in this framework is designed to build, analyze and facilitate the knowledge sharing among problem solving practitioners of an organization in order to improve processes and products achievement. During Problem Solving Processes, the intellectual investment of experts is often considerable and the opportunities for expert knowledge exploitation are numerous: decision making, problem solving under uncertainty, and expert configuration. In this paper, our contribution relates to the structuring of a cognitive experience feedback framework, which allows a flexible exploitation of expert knowledge during Problem Solving Processes and a reuse such collected experience. To that purpose, the proposed approach uses the general principles of root cause analysis for identifying the root causes of problems or events, the conceptual graphs formalism for the semantic conceptualization of the domain vocabulary and the Transferable Belief Model for the fusion of information from different sources. The underlying formal reasoning mechanisms (logic-based semantics) in conceptual graphs enable intelligent information retrieval for the effective exploitation of lessons learned from past projects. An example will illustrate the application of the proposed approach of experience feedback processes formalization in the transport industry sector

    Caractérisation structurale d'hydroxydes doubles lamellaires contenant des anions oxométallates (Mo, w) ou acrylate intercalés.

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    De nouveaux hydroxydes doubles lamellaires (LDHs) contenant des entitĂ©s oxomĂ©tallates (Mo,W) intercalĂ©es ont Ă©tĂ© prĂ©parĂ©s et caractĂ©risĂ©s par diffraction des rayons X (DRX),analyse chimique,spectroscopie infrarouge (IR)et EXAFS.Dans les deux cas,des anions M2O72- (M =Mo,W) constituĂ©s de deux tĂ©traĂšdres Ă  sommet commun, sont intercalĂ©s. L'Ă©volution structurale des phases LDHs contenant des ions oxomĂ©tallates libres dans l'espace interfeuillet, traitĂ©es thermiquement jusqu'Ă  800°C, a Ă©tĂ© Ă©tudiĂ©e. Il a ainsi Ă©tĂ© montrĂ© que les anions oxomĂ©tallates se greffent Ă  deux feuillets adjacents au voisinage de 200°C. Le comportement thermique de phases contenant des anions carbonate intercalĂ©s a Ă©galement Ă©tĂ© apprĂ©hendĂ© par DRX in et ex situ, spectroscopie IR,analyse chimique et thermogravimĂ©trie couplĂ©e Ă  la spectromĂ©trie de masse. Il a Ă©tĂ© mis en Ă©vidence un mono-greffage des anions carbonate aux feuillets. L'intercalation et l'oligomĂ©risation d'anions acrylate dans les LDHs ont Ă©galement Ă©tĂ© rĂ©alisĂ©es. Des diffĂ©rences de comportement sont observĂ©es selon la nature de l'ion substituant du nickel (Fe,Co ou Mn) dans les feuillets. Dans le cas du fer,la phase contenant les monomĂšres intercalĂ©s a pu ĂȘtre isolĂ©e et caractĂ©risĂ©e, alors que dans le cas du cobalt et du manganĂšse, une polymĂ©risation spontanĂ©e, simultanĂ©ment Ă  l'intercalation dans la matrice, a Ă©tĂ© observĂ©e. Les macromolĂ©cules polymĂ©risĂ©es in situ ont Ă©tĂ© extraites par Ă©change anionique, dĂ©rivatisĂ©es en poly(acrylate de mĂ©thyle) et analysĂ©es par chromatographie d'exclusion stĂ©rique.New layered double hydroxides (LDHs),containing intercalated oxometalate species (Mo,W) were prepared and characterised by X-Ray Diffraction (XRD), chemical analysis, infrared spectroscopy (IR) and EXAFS. In both cases, M2O72- anions (M =Mo,W), made of corner-sharing tetrahedra, are intercalated. The structural evolution of LDHs containing free oxometalate species, thermally treated up to 800°C, was studied, showing that the oxometalate anions are grafted to two adjacent slabs at 200°C. The thermal behaviour of carbonate-intercalated LDHs was also studied by in and ex situ XRD, IR spectroscopy, chemical analysis and thermogravimetry, coupled with mass spectrometry. A mono-grafting of the carbonate anions to the slabs was shown. The intercalation and oligomerisation of acrylate anions into LDHs were also performed. Different behaviour are observed, depending on the substituting metal ion for nickel (Fe,Co or Mn) within the slab. In the case of iron, the monomer-intercalated phase could be isolated and characterised, while in the case of cobalt and manganese, a spontaneous polymerisation occurs, simultaneously to the intercalation. The macromolecules, polymerised in situ, were extracted by anionic exchange reaction, derivatised into poly(mĂ©thyl acrylate), and analysed by size exclusion chromatography

    Multi-scale engineering for neuronal cell growth and differentiation

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    In this paper we investigate the role of micropatterning and molecular coating for cell culture and differentiation of neuronal cells (Neuro2a cell line) on a polydimethylsiloxane substrate. We investigate arrays of micrometric grooves (line and space) capable to guide neurite along their axis. We demonstrate that pattern dimensions play a major role due to the deformation of the cell occasioned by grooves narrower than typical cell dimension. A technological compromise for optimizing cell density, differentiation rate and neurite alignment has been obtained for 20 lm wide grooves which is a dimension comparable with the average cell dimension. This topographical engineered pattern combined with double-wall carbon nanotubes coating enabled us to obtain adherent cell densities in the order of 104 cells/cm2 and a differentiation rate close to 100%

    Revisiting the missing protein-coding gene catalog of the domestic dog

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    <p>Abstract</p> <p>Background</p> <p>Among mammals for which there is a high sequence coverage, the whole genome assembly of the dog is unique in that it predicts a low number of protein-coding genes, ~19,000, compared to the over 20,000 reported for other mammalian species. Of particular interest are the more than 400 of genes annotated in primates and rodent genomes, but missing in dog.</p> <p>Results</p> <p>Using over 14,000 orthologous genes between human, chimpanzee, mouse rat and dog, we built multiple pairwise synteny maps to infer short orthologous intervals that were targeted for characterizing the canine missing genes. Based on gene prediction and a functionality test using the ratio of replacement to silent nucleotide substitution rates (<it>d</it><sub>N</sub>/<it>d</it><sub>S</sub>), we provide compelling structural and functional evidence for the identification of 232 new protein-coding genes in the canine genome and 69 gene losses, characterized as undetected gene or pseudogenes. Gene loss phyletic pattern analysis using ten species from chicken to human allowed us to characterize 28 canine-specific gene losses that have functional orthologs continuously from chicken or marsupials through human, and 10 genes that arose specifically in the evolutionary lineage leading to rodent and primates.</p> <p>Conclusion</p> <p>This study demonstrates the central role of comparative genomics for refining gene catalogs and exploring the evolutionary history of gene repertoires, particularly as applied for the characterization of species-specific gene gains and losses.</p

    Genetic diversity of canine olfactory receptors

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    <p>Abstract</p> <p>Background</p> <p>Evolution has resulted in large repertoires of olfactory receptor (OR) genes, forming the largest gene families in mammalian genomes. Knowledge of the genetic diversity of olfactory receptors is essential if we are to understand the differences in olfactory sensory capability between individuals. Canine breeds constitute an attractive model system for such investigations.</p> <p>Results</p> <p>We sequenced 109 OR genes considered representative of the whole OR canine repertoire, which consists of more than 800 genes, in a cohort of 48 dogs of six different breeds. SNP frequency showed the overall level of polymorphism to be high. However, the distribution of SNP was highly heterogeneous among OR genes. More than 50% of OR genes were found to harbour a large number of SNP, whereas the rest were devoid of SNP or only slightly polymorphic. Heterogeneity was also observed across breeds, with 25% of the SNP breed-specific. Linkage disequilibrium within OR genes and OR clusters suggested a gene conversion process, consistent with a mean level of polymorphism higher than that observed for introns and intergenic sequences. A large proportion (47%) of SNP induced amino-acid changes and the Ka/Ks ratio calculated for all alleles with a complete ORF indicated a low selective constraint with respect to the high level of redundancy of the olfactory combinatory code and an ongoing pseudogenisation process, which affects dog breeds differently.</p> <p>Conclusion</p> <p>Our demonstration of a high overall level of polymorphism, likely to modify the ligand-binding capacity of receptors distributed differently within the six breeds tested, is the first step towards understanding why Labrador Retrievers and German Shepherd Dogs have a much greater potential for use as sniffer dogs than Pekingese dogs or Greyhounds. Furthermore, the heterogeneity in OR polymorphism observed raises questions as to why, in a context in which most OR genes are highly polymorphic, a subset of these genes is not? This phenomenon may be related to the nature of their ligands and their importance in everyday life.</p

    Analysis reuse exploiting taxonomical information and belief assignment in industrial problem solving

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    To take into account the experience feedback on solving complex problems in business is deemed as a way to improve the quality of products and processes. Only a few academic works, however, are concerned with the representation and the instrumentation of experience feedback systems. We propose, in this paper, a model of experiences and mechanisms to use these experiences. More specifically, we wish to encourage the reuse of already performed expert analysis to propose a priori analysis in the solving of a new problem. The proposal is based on a representation in the context of the experience of using a conceptual marker and an explicit representation of the analysis incorporating expert opinions and the fusion of these opinions. The experience feedback models and inference mechanisms are integrated in a commercial support tool for problem solving methodologies. The results obtained to this point have already led to the definition of the role of ‘‘Rex Manager’’ with principles of sustainable management for continuous improvement of industrial processes in companies

    A geometric morphometric approach to the study of variation of shovel-shaped incisors

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    Objectives: The scoring and analysis of dental nonmetric traits are predominantly accomplished by using the Arizona State University Dental Anthropology System (ASUDAS), a standard protocol based on strict definitions and three‐dimensional dental plaques. However, visual scoring, even when controlled by strict definitions of features, visual reference, and the experience of the observer, includes an unavoidable part of subjectivity. In this methodological contribution, we propose a new quantitative geometric morphometric approach to quickly and efficiently assess the variation of shoveling in modern human maxillary central incisors (UI1). Materials and methods: We analyzed 87 modern human UI1s by means of virtual imaging and the ASU‐UI1 dental plaque grades using geometric morphometrics by placing semilandmarks on the labial crown aspect. The modern human sample was composed of individuals from Europe, Africa, and Asia and included representatives of all seven grades defined by the ASUDAS method. Results: Our results highlighted some limitations in the use of the current UI1 ASUDAS plaque, indicating that it did not necessarily represent an objective gradient of expression of a nonmetric tooth feature. Rating of shoveling tended to be more prone to intra‐ and interobserver bias for the highest grades. In addition, our analyses suggest that the observers were strongly influenced by the depth of the lingual crown aspect when assessing the shoveling. Discussion: In this context, our results provide a reliable and reproducible framework reinforced by statistical results supporting the fact that open scale numerical measurements can complement the ASUDAS method

    A geometric morphometric approach to the study of variation of shovel‐shaped incisors

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    Objectives : The scoring and analysis of dental nonmetric traits are predominantly accomplished by using the Arizona State University Dental Anthropology System (ASUDAS), a standard protocol based on strict definitions and three‐dimensional dental plaques. However, visual scoring, even when controlled by strict definitions of features, visual reference, and the experience of the observer, includes an unavoidable part of subjectivity. In this methodological contribution, we propose a new quantitative geometric morphometric approach to quickly and efficiently assess the variation of shoveling in modern human maxillary central incisors (UI1).; Materials and methods : We analyzed 87 modern human UI1s by means of virtual imaging and the ASU‐UI1 dental plaque grades using geometric morphometrics by placing semilandmarks on the labial crown aspect. The modern human sample was composed of individuals from Europe, Africa, and Asia and included representatives of all seven grades defined by the ASUDAS method.; Results : Our results highlighted some limitations in the use of the current UI1 ASUDAS plaque, indicating that it did not necessarily represent an objective gradient of expression of a nonmetric tooth feature. Rating of shoveling tended to be more prone to intra‐ and interobserver bias for the highest grades. In addition, our analyses suggest that the observers were strongly influenced by the depth of the lingual crown aspect when assessing the shoveling.; Discussion : In this context, our results provide a reliable and reproducible framework reinforced by statistical results supporting the fact that open scale numerical measurements can complement the ASUDAS method.Facultad de Ciencias Naturales y MuseoConsejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnica

    Elucidation of the Role of Carbon Nanotube Patterns on the Development of Cultured Neuronal Cells.

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    Carbon nanotubes (CNTs) promise various novel neural biomedical applications for interfacing neurons with electronic devices or to design appropriate biomaterials for tissue regeneration. In this study, we use a new methodology to pattern SiO2 cell culture surfaces with double-walled carbon nanotubes (DWNTs). In contrast to homogeneous surfaces, patterned surfaces allow us to investigate new phenomena about the interactions between neural cells and CNTs. Our results demonstrate that thin layers of DWNTs can serve as effective substrates for neural cell culture. Growing neurons sense the physical and chemical properties of the local substrate in a contact-dependent manner and retrieve essential guidance cues. Cells exhibit comparable adhesion and differentiation scores on homogeneous CNT layers and on a homogeneous control SiO2 surface. Conversely, on patterned surfaces, it is found that cells preferentially grow on CNT patterns and that neurites are guided by micrometric CNT patterns. To further elucidate this observation, we investigate the interactions between CNTs and proteins that are contained in the cell culture medium by using quartz crystal microbalance measurements. Finally, we show that protein adsorption is enhanced on CNT features and that this effect is thickness dependent. CNTs seem to act as a sponge for culture medium elements, possibly explaining the selectivity in cell growth localization and differentiation

    Identification of Genomic Regions Associated with Phenotypic Variation between Dog Breeds using Selection Mapping

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