360 research outputs found

    Localisation pédestre : Synthèse bibliographique et illustration d'une approche par vision monoculaire embarquée

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    National audienceLocate our position is one of the tasks we naturally do with our view and our memory. However, ensuring this task in an artificial way is still a challenge for the whole community of computer vision. This paper presents a detailed literature review of pedestrian localization systems and their technologies. In the context of the visually impaired pedestrian navigation assistance, we also present an innovative solution based on the vision localization for both outdoor and indoor navigation. This new solution is established based on the independence of any collective equipment.Se localiser est une des tâches que nous faisons naturellement grâce à notre vue et notre mémoire. Cependant, l'assurer artificiellement demeure un défi pour toute la communauté de la vision par ordinateur. Cette communication présente une revue de la littérature détaillée des systèmes de localisation pédestre et de ses technologies. Dans le contexte de l'assistance à la navigation pédestre des déficients visuels, nous proposons aussi une solution innovante, pour un fonctionnement efficace aussi bien en extérieur qu'en intérieur, fondée sur l'indépendance vis-à-vis de l'équipement collectif

    Functional characterization of CaVα2δ mutations associated with sudden cardiac death

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    L-type Ca(2+) channels play a critical role in cardiac rhythmicity. These ion channels are oligomeric complexes formed by the pore-forming CaVα1 with the auxiliary CaVβ and CaVα2δ subunits. CaVα2δ increases the peak current density and improves the voltage-dependent activation gating of CaV1.2 channels without increasing the surface expression of the CaVα1 subunit. The functional impact of genetic variants of CACNA2D1 (the gene encoding for CaVα2δ), associated with shorter repolarization QT intervals (the time interval between the Q and the T waves on the cardiac electrocardiogram), was investigated after recombinant expression of the full complement of L-type CaV1.2 subunits in human embryonic kidney 293 cells. By performing side-by-side high resolution flow cytometry assays and whole-cell patch clamp recordings, we revealed that the surface density of the CaVα2δ wild-type protein correlates with the peak current density. Furthermore, the cell surface density of CaVα2δ mutants S755T, Q917H, and S956T was not significantly different from the cell surface density of the CaVα2δ wild-type protein expressed under the same conditions. In contrast, the cell surface expression of CaVα2δ D550Y, CaVα2δ S709N, and the double mutant D550Y/Q917H was reduced, respectively, by ≈30-33% for the single mutants and by 60% for the latter. The cell surface density of D550Y/Q917H was more significantly impaired than protein stability, suggesting that surface trafficking of CaVα2δ was disrupted by the double mutation. Co-expression with D550Y/Q917H significantly decreased CaV1.2 currents as compared with results obtained with CaVα2δ wild type. It is concluded that D550Y/Q917H reduced inward Ca(2+) currents through a defect in the cell surface trafficking of CaVα2δ. Altogether, our results provide novel insight in the molecular mechanism underlying the modulation of CaV1.2 currents by CaVα2δ

    Are concomitant treatments confounding factors in randomized controlled trials on intensive blood-glucose control in type 2 diabetes? a systematic review

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    International audienceBackgroundOpen-label, randomized controlled trials (RCTs) are subject to observer bias. If patient management is conducted without blinding, a difference between groups may be explained by other factors than study treatment. One factor may come from taking concomitant treatments with an efficacy on the studied outcomes. In type 2 diabetes, some antihypertensive or lipid-lowering drugs are effective against diabetic complications. We wanted to determine if these concomitant treatments were correctly reported in articles of RCTs on type 2 diabetes and if they might have influenced the outcome.MethodsWe performed a systematic review using Medline, Embase, and the Cochrane Library (from January 1950 to July 2010). Open-label RCTs assessing the effectiveness of intensive blood-glucose control in type 2 diabetes were included. We chose five therapeutic classes with proven efficacy against diabetes complications: angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor antagonists (AIIRAs), fibrates, statins, and aspirin. Differences between concomitant treatments were considered statistically significant when p ResultsA total of eight open-label RCTs were included, but only three (37.5%) of them published concomitant treatments. In two studies (ACCORD and ADVANCE), a statistically significant difference was observed between the two groups for aspirin (p = 0.02) and ACEIs (p = 0.02).ConclusionsFew concomitant treatments were published in this sample of open-label RCTs. We cannot completely eliminate an observer bias for these studies. This bias probably influenced the results to an extent that has yet to be determined

    Decrease in ovalbumin-induced pulmonary allergic response by benzaldehyde but not acetaldehyde exposure in a guinea pig model

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    International audienceThe pulmonary effects of two environmentally relevant aldehydes were investigated in non-sensitized or ovalbumin (OA)-sensitized guinea pigs (GPs). Four-week-old male Hartley GPs, weighing about 400 g, were intraperitoneally injected with 1 ml of an NaCl solution containing 100 mug OA and 100 mg Al/(OH)(3). They were then exposed to either acetaldehyde (200 ppb) or benzaldehyde (500 ppb) (or 4 wk (6 h/d, 5 d/wk). At the end of exposure, GPs were challenged with an OA aerosol (0.1% in NaCl) and pulmonary functions were measured. The day after, guinea pigs were anesthetized and several endpoints related to inflammatory anti allergic responses were assessed in blood, whole-lung histology, and bronchoalveolar lavage (BAL). Sensitized nonexposed GPs showed bronchial hyperresponsiveness to OA and an increased number of eosinophils in blood and BAL, together with a rise in total protein and leukotrienes (LTB4 and LTC4/D-4/E-4) in BAL. In nonsensitized GPs, exposure to acetaldehyde or benzaldehyde did not induce any change in the tested parameters;, with the exception of irritation of the respiratory tract as detected by histology and an increased number of alveolar macrophages in animals exposed to acetaldehyde. In sensitized GPs, exposure to acetaldehyde induced a moderate irritation of the respiratory tract but no change in biological parameters linked to the inflammatory and allergic responses, In contrast, exposure to benzaldehyde induced a decrease both in OA-induced bronchoconstriction and in eosinophil and neutrophil numbers in BAL, an increase in the bronchodilatator mediator prostaglandin E-2 (PGE(2)) and a decrease in the bronchoconstrictor mediators LTC4/D-4/E-4. Further investigations are needed to determine if the attenuated response observed in sensitized GPs exposed to benzaldehyde is due to an alteration of the mechanism of sensitization or to a more direct effect on various mechanisms of the allergic response

    High-Resolution Profiling of Innate Immune Responses by Porcine Dendritic Cell Subsets in vitro and in vivo

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    The present study investigated the transcriptomic response of porcine dendritic cells (DC) to innate stimulation in vitro and in vivo. The aim was to identify DC subset-specialization, suitable Toll-like receptor (TLR) ligands targeting plasmacytoid DC (pDC), and the DC activation profile during highly and low virulent classical swine fever virus (CSFV, strain Eystrup and Pinar del Rio, respectively) infection, chosen as model for a virus causing a severe immunopathology. After identification of porcine conventional DC (cDC) 1, cDC2, pDC and a monocyte-derived subset in lymphoid tissues, we characterized DC activation using transcriptomics, and focused on chemokines, interferons, cytokines, as well as on co-stimulatory and inhibitory molecules. We demonstrate that porcine pDC provide important signals for Th1 and interferon responses, with CpG triggering the strongest responses in pDC. DC isolated early after infection of pigs with either of the two CSFV strains showed prominent upregulation of CCL5, CXCL9, CXCL10, CXCL11, and XCL1, as well as of the cytokines TNFSF13B, IL6, IL7, IL12B, IL15, IL27. Transcription of IL12B and many interferon genes were mostly restricted to pDC. Interestingly, the infection was associated with a prominent induction of inhibitory and cell death receptors. When comparing low and highly virulent CSFV strains, the latter induced a stronger inflammatory and antiviral response but a weaker cell cycle response, and reduced antigen presentation functions of DC. Taken together, we provide high-resolution information on DC activation in pigs, as well as information on how DC modulation could be linked to CSFV immunopathology.info:eu-repo/semantics/publishedVersio

    Transitions - Note 9

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    Note complète ; Résumé ; Capsule: l'accès des EPG aux universités canadiennes

    Découverte fortuite de stèles antiques à Niederhergheim (Haut-Rhin)

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    Sept monuments funéraires antiques, quatre stèles figurées et trois stèles plaques, ainsi que deux blocs simplement dégrossis au pic ont été mis au jour fortuitement en juin 2011 à Niederhergheim (Haut-Rhin), lors de travaux d’assainissement rue d’Oberhergheim. Cet ensemble, découvert en situation de remploi, est remarquable par la qualité des éléments sculptés, à la fois tous différents les uns des autres par la composition et les thèmes représentés et pourtant très proches, au moins pour trois d'entre eux, dans le style d’exécution, qui pourrait être révélateur d’une même marque de fabrique.Seven Antique funerary monuments, four figurative steles, three plaque steles, and two blocks simply roughed-out with a pick, were accidentally discovered in June 2011 in Niederhergheim (Haut-Rhin) during sanitation work on the rue d’Oberhergheim. These remains, discovered in a situation of reuse, is remarkable for the quality of the sculpted elements, both different from each other in the compositions and themes represented, and very similar, at least for three of them, in their execution style, which could reveal a single trademark.Bei Sanierungsarbeiten wurden im Juni 2011 in Niederhergheim (Departement Haut-Rhin) in der rue d’Oberhergheim zufällig sieben antike Grabmonumente, vier Grabsteine mit figürlichen Darstellungen und drei Plattenstelen, sowie zwei nur grob behaue Blöcke freigelegt. Diese als Spolien wiederverwendeten Grabplastiken zeichnen sich durch die bildhauerische Qualität der Darstellungen aus, deren Komposition und Themen zwar Unterschiede doch zugleich große Ähnlichkeit aufweisen. Der Stil der Ausführung, der zumindest bei drei der Grabplastiken sehr ähnlich ist, könnte auf die Herkunft aus der gleichen Werkstatt weisen

    ANGULAR RESOLUTION LIMIT FOR VECTOR-SENSOR ARRAYS: DETECTION AND INFORMATION THEORY APPROACHES

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    ABSTRACT The Angular Resolution Limit (ARL) on resolving two closely spaced polarized sources using vector-sensor arrays is considered in this paper. The proposed method is based on the information theory. In particular, the Stein's lemma provides, asymptotically, a link between the probability of false alarm and the relative entropy between two hypothesis of a given statistical binary test. We show that the relative entropy can be approximated by a quadratic function in the ARL. This property allows us to derive and analyze a closed-form expression of the ARL. To illustrate the interest of our approach, the ARL, in the sense of the detection theory, is also derived. Finally, we show that the ARL is only sensitive to the norm of the polarization state vector and not to the particular values of the polarization parameters
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