493 research outputs found

    Sensitivity of optical correlation to color change of target images

    No full text
    International audienceOptical correlation is based on the comparison of contours between an unknown target image and a known reference image. However, it does not usually include the color image information in the decision making process. In order to render the correlation method sensitive to color change, we propose a general method based on the decomposition of the target image in its three color components using, either the normalized RGB (red, green, blue) color space, or the normalized HSV (hue, saturation, value) space. Then, the correlation operation is carried out for each color component and the results are merged in order to make a decision. The aforementioned steps can alleviate some of the problems associated with illumination changes in the target image but do utilize color information of the target image. To overcome these problems, we propose to convert the color information in contour information into a signature corresponding to the color information of the target image. This technique and test results are presented to validate its effectiveness. The preliminary results obtained with this technique are encouraging

    Added value of IP-10 as a read-out of <em>Mycobacterium tuberculosis</em>:Specific immunity in young children

    Get PDF
    We have explored the added value of interferon-γ (IFNγ)–inducible protein 10 as a read-out of Mycobacterium tuberculosis–specific immunity in young Indian children, where the sensitivity of the IFNγ release assays for tuberculosis is poor. Reduced frequency of indeterminate results and an increased sensitivity for tuberculosis suggest a potential for fewer missed cases with a combined IFNγ/inducible protein 10 read-out in a 4th generation IFNγ release assays

    Mitmachen unbedingt erwünscht

    Get PDF
    Zunehmend halten neue Veranstaltungsformate und digitale Anwendungen Einzug in den Wissenstransfer. Durch die Förderung eines interaktiven Miteinanders können Teilnehmende zu Mitgestaltern werden

    Iterative Methods for Visualization of Implicit Surfaces on GPU

    Get PDF
    The original publication is available at www.springerlink.comInternational audienceThe ray-casting of implicit surfaces on GPU has been explored in the last few years. However, until recently, they were restricted to second degree (quadrics). We present an iterative solution to ray cast cubics and quartics on GPU. Our solution targets efficient implementation, obtaining interactive rendering for thousands of surfaces per frame. We have given special attention to torus rendering since it is a useful shape for multiple CAD models. We have tested four different iterative methods, including a novel one, comparing them with classical tessellation solution

    Determinación del curso temporal de fluoxetina y norfluoxetinaen perros Pastor Alemán y Akita Inu

    Get PDF
    Indexación ScopusThe pharmacokinetics of fluoxetine were evaluated in two phylogenetically distant dog breeds. The quantification method was fine-tuned and validated through the mean, standard deviation and coefficient of variation (CV) for each sampling point. The CV values were around 2%. The detection limit was 3.36 ng/ml and corresponded to three times the signal noise of the blank sample. The limit of quantification (LOQ) was 10.53 ng/ ml. The chromatographic analysis indicated that the maximum concentrations of fluoxetine were reached at two hours post-administration (Akika Inu: 41.8 ± 0.6 ng/ml; German Shepherd: 45.3 ± 1.4.0 ng/ml), while the minimum concentrations were reached at 80 hours (Akika Inu: 3.9 ± 0.1 ng/ml; German Shepherd: 3.9 ± 0.1 ng/ml). A significant difference between breeds was only found in the values reached at 2 h post-administration (p<0.05). Results may indicate that due to the differences in the time curve, drug management might be different between phylogenetically different breeds. © 2020 Universidad Nacional Mayor de San Marcos. All rights reserved.https://revistas.gnbit.net/index.php/veterinaria/article/view/1763

    A molecular dynamics study on the equilibrium magnetization properties and structure of ferrofluids

    Full text link
    We investigate in detail the initial susceptibility, magnetization curves, and microstructure of ferrofluids in various concentration and particle dipole moment ranges by means of molecular dynamics simulations. We use the Ewald summation for the long-range dipolar interactions, take explicitly into account the translational and rotational degrees of freedom, coupled to a Langevin thermostat. When the dipolar interaction energy is comparable with the thermal energy, the simulation results on the magnetization properties agree with the theoretical predictions very well. For stronger dipolar couplings, however, we find systematic deviations from the theoretical curves. We analyze in detail the observed microstructure of the fluids under different conditions. The formation of clusters is found to enhance the magnetization at weak fields and thus leads to a larger initial susceptibility. The influence of the particle aggregation is isolated by studying ferro-solids, which consist of magnetic dipoles frozen in at random locations but which are free to rotate. Due to the artificial suppression of clusters in ferro-solids the observed susceptibility is considerably lowered when compared to ferrofluids.Comment: 33 pages including 12 figures, requires RevTex

    Homophily and Contagion Are Generically Confounded in Observational Social Network Studies

    Full text link
    We consider processes on social networks that can potentially involve three factors: homophily, or the formation of social ties due to matching individual traits; social contagion, also known as social influence; and the causal effect of an individual's covariates on their behavior or other measurable responses. We show that, generically, all of these are confounded with each other. Distinguishing them from one another requires strong assumptions on the parametrization of the social process or on the adequacy of the covariates used (or both). In particular we demonstrate, with simple examples, that asymmetries in regression coefficients cannot identify causal effects, and that very simple models of imitation (a form of social contagion) can produce substantial correlations between an individual's enduring traits and their choices, even when there is no intrinsic affinity between them. We also suggest some possible constructive responses to these results.Comment: 27 pages, 9 figures. V2: Revised in response to referees. V3: Ditt
    corecore