112 research outputs found

    L’autodétermination des peuples comme principe juridique

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    Intelligent Vehicle embedded sensors fault detection and identification using analytical redundancy and non-linear transformations

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    This work proposes a fault detection architecture for a vehicle embedded sensors, allowing to deal with both system non-linearity and environmental disturbances and degradations. The proposed method use measurements analytical redundancy and a non-linear transformation to generate the residual value allowing the fault detection. A strategy dedicated to the optimization of the detection parameters choice is also develope

    Improved Low Cost GPS Localization By Using Communicative Vehicles

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    International audienceIn this paper, a new collaborative localization method is proposed. On the assumption that the distance between two communicative vehicles can be calculated with a good precision, cooperative vehicle are considered as additional satellites into the user position calculation by using iterative methods. In order to limit divergence, some filtering process is proposed: Interacting Multiple Model (IMM) is used to guarantee a greater robustness in the user position estimation

    The Geographical Deconcentration of Scientific Activity (1987-2007)

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    Texte intégral à l'adresse : http://sticonference.org/Proceedings/vol1/Grossetti_Geographical_348.pdfTraditional research on "world cities" tends to develop the idea that large, inter-connected agglomerations can better take advantage of international competition. This suggests that we should observe an increasing concentration of activities in these cities at the expense of smaller ones. Among analyses using measures based on scientific publications, certain studies support this hypothesis. Others however, show that in certain countries such as China, an opposite trend is emerging; the largest cities are undergoing a relative decline in the country's scientific activities. To go beyond this seeming contradiction, this paper provides a global analysis of all countries having papers in Thomson Reuters 'Web of Science' over the period 1987-2007. The addresses -present in each article- were geo-coded and then grouped into agglomerations. The result of our analysis is unambiguous: deconcentration is clearly the dominant trend -both: globally and within countries-, despite some rare exceptions for which explanations are suggested

    Cities and the geografical deconcentration of scientific activity : A multilevel analysis of publications (1987-2007)

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    International audienceMost current scientific policies incorporate debates on cities and the geographic organisation of scientific activity. Research on 'world cities' develops the idea that interconnected agglomerations can better take advantage of international competition. Thus, the increasing concentration of activities in these cities at the expense of others could be observed by certain scholars using measures based on scientific publications. Others, however, show that an opposite trend is emerging: the largest cities are undergoing a relative decline in a country's scientific activities. To go beyond this seeming contradiction, this paper provides a global analysis of all countries with papers in the Web of Science over the period 1987-2007. The author's addresses were geocoded and grouped into agglomerations. Registering of papers was based on the fractional counting of multi-authored publications, and the results are unambiguous: deconcentration is the dominant trend both globally and within countries, with some exceptions for which explanations are suggestedBeijing (Pékin), Tokyo, Paris, New York, Séoul, Londres... les grands foyers de la science pèsent moins que par le passé du fait d'une déconcentration géographique au niveau mondial. Tel est le résultat de l'analyse statistique systématique menée par des scientifiques du Laboratoire interdisciplinaire solidarités, sociétés, territoires (CNRS/Université de Toulouse II-Le Mirail/EHESS) sur des millions d'articles de publications scientifiques, édités entre 1987 et 2007 dans des milliers de revues scientifiques recensées par le Web of Science. Ces travaux sont les premiers à s'intéresser à la géographie de la science au niveau de l'ensemble des villes mondiales

    Activation of the extracellular signal-regulated protein kinase (ERK) cascade by membrane-type-1 matrix metalloproteinase (MT1-MMP)

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    AbstractThe mechanisms underlying membrane-type-1 matrix metalloproteinase (MT1-MMP)-dependent induction of cell migration were investigated. Overexpression of MT1-MMP induced a marked increase in cell migration, this increase being dependent on the presence of the cytoplasmic domain of the protein. MT1-MMP-dependent migration was inhibited by a mitogen-activated protein kinase kinase 1 inhibitor, suggesting the involvement of the extracellular signal-regulated protein kinase (ERK) cascade in the induction of migration. Accordingly, MT1-MMP overexpression induced the activation of ERK, this process being also dependent on the presence of its cytoplasmic domain. MT1-MMP-induced activation of both migration and ERK required the catalytic activity of the enzyme as well as attachment of the cells to matrix proteins. The MT1-MMP-dependent activation of ERK was correlated with the activation of transcription through the serum response element, whereas other promoters were unaffected. Taken together, these results indicate that MT1-MMP trigger important changes in cellular signal transduction events, leading to cell migration and to gene transcription, and that these signals possibly originate from the cytoplasmic domain of the protein

    A New Technique for Integrating MEMS-Based Low-Cost IMU and GPS in Vehicular Navigation

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    In providing acceptable navigational solutions, Location-Based Services (LBS) in land navigation rely mostly on integration of Global Positioning System (GPS) and Inertial Navigation System (INS) measurements for accuracy and robustness. The GPS/INS integrated system can provide better land-navigation solutions than the ones any standalone system can provide. Low-cost Inertial Measurement Units (IMUs), based on Microelectromechanical Systems (MEMS) technology, revolutionized the land-navigation system by virtue of their low-cost miniaturization and widespread availability. However, their accuracy is strongly affected by their inherent systematic and stochastic errors, which depend mainly on environmental conditions. The environmental noise and nonlinearities prevent obtaining optimal localization estimates in Land Vehicular Navigation (LVN) while using traditional Kalman Filters (KF). The main goal of this paper is to effectively eliminate stochastic errors of MEMS-based IMUs. The proposed solution is divided into two main components: (1) improving noise cancellation, using advanced stochastic error models in MEMS-based IMUs based on combined Autoregressive Processes (ARP) and first-order Gauss-Markov Process (1GMP), and (2) modeling the low-cost GPS/INS integration, using a hybrid Fuzzy Inference System (FIS) and Second-Order Extended Kalman Filter (SOEKF). The results obtained show that the proposed methods perform better than the traditional techniques do in different stochastic and dynamic situations

    Identification of membrane-type 1 matrix metalloproteinase tyrosine phosphorylation in association with neuroblastoma progression

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    <p>Abstract</p> <p>Background</p> <p>Neuroblastoma is a pediatric tumor of neural crest cells that is clinically characterized by its variable evolution, from spontaneous regression to malignancy. Despite many advances in neuroblastoma research, 60% of neuroblastoma, which are essentially metastatic cases, are associated with poor clinical outcome due to the lack of effectiveness of current therapeutic strategies. Membrane-type 1 matrix metalloproteinase (MT1-MMP, MMP-14), an enzyme involved in several steps in tumor progression, has previously been shown to be associated with poor clinical outcome for neuroblastoma. Based on our recent demonstration that MT1-MMP phosphorylation is involved in the growth of fibrosarcoma tumors, we examined the potential role of phosphorylated MT1-MMP in neuroblastoma progression.</p> <p>Methods</p> <p>Tyrosine phosphorylated MT1-MMP was immunostained on tissue microarray samples from 55 patients with neuroblastoma detected by mass screening (known to be predominantly associated with favourable outcome), and from 234 patients with standard diagnosed neuroblastoma. In addition, the effects of a non phosphorylable version of MT1-MMP on neuroblastoma cell migration and proliferation were investigated within three-dimensional collagen matrices.</p> <p>Results</p> <p>Although there is no correlation between the extent of tyrosine phosphorylation of MT1-MMP (pMT1-MMP) and MYCN amplification or clinical stage, we observed greater phosphorylation of pMT1-MMP in standard neuroblastoma, while it is less evident in neuroblastoma from mass screening samples (P = 0.0006) or in neuroblastoma samples from patients younger than one year (P = 0.0002). <it>In vitro </it>experiments showed that overexpression of a non-phosphorylable version of MT1-MMP reduced MT1-MMP-mediated neuroblastoma cell migration and proliferation within a three-dimensional type I collagen matrix, suggesting a role for the phosphorylated enzyme in the invasive properties of neuroblastoma cells.</p> <p>Conclusion</p> <p>Overall, these results suggest that tyrosine phosphorylated MT1-MMP plays an important role in neuroblastoma progression and that its expression is preferentially observed in tumor specimens from neuroblastoma patients showing poor clinical outcome.</p

    Using historical accounts of harpsichord touch to empirically investigate the production and perception of dynamics on the 1788 Taskin.

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    This article investigates the extent of production and perception of dynamic differences on a French historical harpsichord, extensively revised in 1788 by Pascal Taskin. A historical review reports on the descriptions of two different types of touch found in treatises of the 18th century. These two touches (loud/struck and soft/pressed) were used to perform single tones on the lower, upper, peau de buffle (PDB) registers (the last of which Taskin is credited with having invented) and the coupled 8-foot registers to investigate differences in dynamics. Acoustic measurements show varied differences of up to 11 dB for the two types of touch over different pitches in each register. The strongest difference is measured in the first harmonic of note F2 on the PDB. A listening experiment was conducted to test whether these differences are perceivable. Participants performed a discrimination task using pairs of single tones. Participants were able to perform significantly better than chance in correctly identifying whether pairs of single tones were same or different with respect to loudness [t(24) = 12.01, p < 0.001]. Accuracies were influenced by pitch and register, the PDB providing the strongest accuracies over the four registers tested
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