91 research outputs found

    Saliency on a chip: a digital approach with an FPGA

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    Selective-visual-attention algorithms have been successfully implemented in analog VLSI circuits.1 However, in addition to the usual issues of analog VLSI—such as the need to fi ne-tune a large number of biases— these implementations lack the spatial resolution and pre-processing capabilities to be truly useful for image-processing applications. Here we take an alternative approach and implement a neuro-mimetic algorithm for selective visual attention in digital hardware

    Présence de métaux lourds et de résidus médicamenteux dans les effluents des établissements de santé de Dakar (Sénégal)

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    L’objectif de cette Ă©tude est de quantifier les concentrations en mĂ©taux lourds et de rechercher la prĂ©sence de rĂ©sidus de molĂ©cules mĂ©dicamenteuses des effluents de trois hĂŽpitaux de Dakar (SĂ©nĂ©gal). C’est ainsi que la collecte des effluents a Ă©tĂ© rĂ©alisĂ©e chaque jour sur une pĂ©riode de trois semaines Ă  l’entrĂ©e du dĂ©versoir des services de radiologie, de mĂ©decine interne et d’odontologie. Ensuite, des Ă©chantillons composites par semaine ont Ă©tĂ© constituĂ©s pour rechercher leur composition en mĂ©taux lourds et en rĂ©sidus mĂ©dicamenteux. Le transport a Ă©tĂ© effectuĂ© Ă  +4 °C et Ă  l'obscuritĂ© pour assurer une conservation satisfaisante. Les mĂ©taux lourds ont Ă©tĂ© dosĂ©s par ICP-MS et les rĂ©sidus de mĂ©dicaments ont Ă©tĂ© recherchĂ©s par UPLCMS/ MS. Les mĂ©dicaments identifiĂ©s dans les effluents sont essentiellement des analgĂ©siques et des psychotropes. La concentration en mĂ©taux lourds des effluents des trois hĂŽpitaux est infĂ©rieure aux normes sĂ©nĂ©galaises et de celles de L’OMS fixant les conditions de rejet de mĂ©taux dans les eaux usĂ©es. Cependant, bien que les taux retrouvĂ©s soient tolĂ©rables, leur introduction continuelle en milieu aquatique pourrait ĂȘtre Ă  l’origine d’effets nĂ©fastes sur les organismes marins par des phĂ©nomĂšnes de bioaccumulation et de biomagnification. D’oĂč l’importance et la nĂ©cessitĂ© des stations d’épuration pour une bonne gestion et une rĂ©duction des risques Ă©cotoxicologiques liĂ©s aux effluents liquides hospitaliers.Mots clĂ©s : Effluents hospitaliers, mĂ©taux lourds, rĂ©sidus mĂ©dicamenteux, toxicitĂ©

    Ion-Induced Dipole Interactions and Fragmentation Times : Cα\alpha -CÎČ\beta Chromophore Bond Dissociation Channel

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    The fragmentation times corresponding to the loss of the chromophore (Cα\alpha-- CÎČ\beta bond dissociation channel) after photoexcitation at 263 nm have been investigated for several small peptides containing tryptophan or tyrosine. For tryptophan-containing peptides, the aromatic chromophore is lost as an ionic fragment (m/z 130), and the fragmentation time increases with the mass of the neutral fragment. In contrast, for tyrosine-containing peptides the aromatic chromophore is always lost as a neutral fragment (mass = 107 amu) and the fragmentation time is found to be fast (\textless{}20 ns). These different behaviors are explained by the role of the postfragmentation interaction in the complex formed after the Cα\alpha--CÎČ\beta bond cleavage

    What Counts as ‘World Class’? : Global University Rankings and Shifts in Institutional Strategies

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    Global university rankings have emerged as a benchmark of institutional success, setting standards for higher education policymaking and institutional practices. Nevertheless, only a marginal share of higher education institutions (HEI) are in a realistic position to be ranked as a ‘world-class’ institutions. In the European context, the global rankings have been used to highlight a performance gap between European and North American institutions. Here the focus has been on the HEIs in the top-100 positions, causing concerns over European higher education. This has also become a marker of world-class university. We analyze the strategies of 27 Northern European universities in different tiers to learn how they have adjusted to the reality of ranking. We conclude that the references to global rankings have increased between 2014 and 2018. At the same time, the references to rankings have become more implicit in nature. Nevertheless, we find that the discourse of global comparison and excellence has become more common in the strategies. There are also emerging references to the regional role of universities, which are apparent in the strategies of universities that are clearly outside the top-100 ranked institutions. However, this is also a reflection of the discourse of world-class university.Peer reviewe
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