A Negotiation Support System based on a Multi-agent System speci city and preference relations on arguments

http://www.di.unipi.it/~morge/publis/morge04sac.pdfInternational audienceIn this paper, we propose a Negotiation Support System based on a Multi-agent System. Each agent assists a user in multi-criteria decision making and negotiates according to this decision-modelling with other agents, each of them representing a user. Moreover agents assist users in the debate to negotiate a joint representation of the problem and automatically justify proposals with this joint representation

Architecture multi-agents pour la composition automatique de web services

http://democritique.org/IT/Documents/Semantic_SOA/Architecture_multi-agents_pour_la_composition_de_web_services.pdfNational audienceLes propositions actuelles de composition automatique de web services atteignent leurs limites dans le cas d'environnements distribués et dynamiques. Nous proposons dans cet article de résoudre ce problème en utilisant la planification distribuée multi-agents. Les agents de notre architecture génèrent collaborativement une description exécutable de service composite, prenant en compte la QoS. ABSTRACT. The existing web service automatic composition approaches are not scaled to dynamic and distributed environments. In this paper, we thus propose to use multi-agent distributed planning. The agents of our architecture collaborate to synthesise an executable description of a QoS-aware composite service

Defining and Modeling Context in a Multi-Agent Systems Architecture for Decision-Making

http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.143.652Ambient intelligence involves the convergence of several computing areas: ubiquitous computing, intelligent systems and context-awareness. Developing context-aware applications needs facilities for recognizing and representing context, reasoning on it and adapting to it accordingly. In what concerns context representation, the newest and most challenging representation is the ontological one. The problem is that current ontologies for context do not provide a standard for representing complex context attributes. In this paper, we propose a context definition and representation used to construct context-based agent architecture. The representation we propose combines the generality provided by ontologies with the complexity inspired by the object oriented models. The goal of the proposed architecture is to support the deployment of context-aware agents able to learn how to recognize the context of their decisions and to adapt to it. The use of this architecture is illustrated on a test MAS for agenda management, using the JADE-LEAP platform on PCs and PDAs

Modeling and Simulating Distributed Industrial Systems - A Multi-Agent Methodological Approach

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.60.2430&rep=rep1&type=pdfDraftWe are located in the context of the industrial system simulation, which are complex and distributed in operational, informational and decisional terms. In this chapter, we present the problems and a methodological solution. This methodology is based on the systemic approach and on multi-agent systems. It allows the modelling of distributed industrial systems such as enterprise consortiums. Moreover, it proposes a software platform architecture whish is currently instanced with Arena and dedicated agents

A New Relational Spatial OLAP Approach For Multi-resolution and Spatio-multidimensional Analysis of Incomplete Field Data

International audienceIntegrating continuous spatial data into SOLAP systems is a new research challenge. Moreover, representation of field data at different scales or resolutions is often mandatory for an effective analysis. Thus, in this paper, we propose a logical model to integrate spatial dimensions representing incomplete field data at different resolutions in a classical SOLAP architecture

Determination of Cytochrome P450 2D6 (CYP2D6) Gene Copy Number by Real-Time Quantitative PCR

Gene dosage by real-time quantitative PCR has proved to be accurate for measuring gene copy number. The aim of this study was to apply this approach to the CYP2D6 gene to allow for rapid identification of poor and ultrarapid metabolizers (0, 1, or more than 2 gene copy number). Using the 2(−ΔΔCt) calculation method and a duplex reaction, the number of CYP2D6 gene copies was determined. Quantitative PCR was performed on 43 samples previously analyzed by Southern blotting and long PCR including 20 samples with a heterozygous deletion, 11 with normal copy number (2 copies), and 12 samples with duplicated genes. The average ratio ranged from 1.02 to 1.28, 1.85 to 2.21, and 2.55 to 3.30, respectively, for the samples with 1 copy, 2 copies, and 3 copies. This study shows that this method is sensitive enough to detect either a heterozygous gene deletion or duplication

Collection of Human Genomic DNA From Buccal Cells for Genetics Studies: Comparison Between Cytobrush, Mouthwash, and Treated Card

Alternative sources such as buccal cells have already been tested for genetic studies and epidemiological investigations. Thirty-seven volunteers participated in this study to compare cytology brushes, mouthwash, and treated cards for DNA collection. Quantity and quality of DNA and cost and feasibility were assessed. The mean DNA yield at 260 nm was found to be 3.5, 4, and 2.6 μg for cytobrushes, mouthwashes, and treated cards, respectively. A second quantification technique by fluorescence showed differences in the DNA yield with 1.1 and 5.2 μg for cytobrushes and mouthwash, respectively. All buccal samples allowed isolation of DNA suitable for polymerase chain reaction. According to the procedure of sample collection, the yield and purity of collected DNA, and storage conditions, the use of cytobrush appears to be the more appropriate method for DNA collection. This protocol has been validated and is currently applied in three large-scale multicentric studies including adults or children

Is the gene encoding Chibby implicated as a tumour suppressor in colorectal cancer ?

BACKGROUND: A novel member of the Wnt signalling pathway, Chibby, was recently identified. This protein inhibits Wnt/β-catenin mediated transcriptional activation by competing with Lef-1 (the transcription factor and target of β-catenin) to bind to β-catenin. This suggests that Chibby could be a tumour suppressor protein. The C22orf2 gene coding Chibby is located on chromosome 22, a region recurrently lost in colorectal cancer. Activation of the Wnt pathway is a major feature of colorectal cancer and occurs through inactivation of APC or activation of β-catenin. All of this led us to analyse the possible implication of Chibby in colorectal carcinogenesis. METHODS: First, 36 tumour and matched normal colonic mucosa DNA were genotyped with five microsatellite markers located on chromosome 22 to search for loss of heterozygosity. Then, mutation screening of the C22orf2 coding sequence and splice sites was performed in the 36 tumour DNA. Finally, expression of Chibby was analysed by quantitative RT-PCR on 10 patients, 4 with loss of heterozygosity (LOH) on chromosome 22. RESULTS: Loss of heterozygosity involving the C22orf2 region was detected in 11 out of 36 patients (30%). Sequencing analysis revealed a known variant, rs3747174, in exon 5: T321C leading to a silent amino acid polymorphism A107A. Allelic frequencies were 0.69 and 0.31 for T and C variants respectively. No other mutation was detected. Among the 10 patients studied, expression analysis revealed that Chibby is overexpressed in 2 tumours and underexpressed in 1. No correlations were found with 22q LOH status. CONCLUSION: As no somatic mutation was detected in C22orf2 in 36 colorectal tumour DNA, our results do not support the implication of Chibby as a tumour suppressor in colorectal carcinogenesis. This was supported by the absence of underexpression of Chibby among the tumour samples with 22q LOH. The implication of other Wnt pathway members remains to be identified to explain the part of colorectal tumours without mutation in APC and β-catenin

Combined transcriptomic-(1)H NMR metabonomic study reveals yhat monoethylhexyl phthalate stimulates adipogenesis and glyceroneogenesis in human adipocytes

Adipose tissue is a major storage site for lipophilic environmental contaminants. The environmental metabolic disruptor hypothesis postulates that some pollutants can promote obesity or metabolic disorders by activating nuclear receptors involved in the control of energetic homeostasis. In this context, monoethylhexyl phthalate (MEHP) is of particular concern since it was shown to activate the peroxisome proliferator-activated receptor γ (PPARγ) in 3T3-L1 murine preadipocytes. In the present work, we used an untargeted, combined transcriptomic-(1)H NMR-based metabonomic approach to describe the overall effect of MEHP on primary cultures of human subcutaneous adipocytes differentiated in vitro. MEHP stimulated rapidly and selectively the expression of genes involved in glyceroneogenesis, enhanced the expression of the cytosolic phosphoenolpyruvate carboxykinase, and reduced fatty acid release. These results demonstrate that MEHP increased glyceroneogenesis and fatty acid reesterification in human adipocytes. A longer treatment with MEHP induced the expression of genes involved in triglycerides uptake, synthesis, and storage; decreased intracellular lactate, glutamine, and other amino acids; increased aspartate and NAD, and resulted in a global increase in triglycerides. Altogether, these results indicate that MEHP promoted the differentiation of human preadipocytes to adipocytes. These mechanisms might contribute to the suspected obesogenic effect of MEHP