27 research outputs found

    On the role of the upper part of words in lexical access : evidence with masked priming

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    More than 100 years ago, Huey (1908) indicated that the upper part of words was more relevant for perception than the lower part. Here we examined whether mutilated words, in their upper/lower portions (e.g., , , , ), can automatically access their word units in the mental lexicon. To that end, we conducted four masked repetition priming experiments with the lexical decision task. Results showed that mutilated primes produced a sizeable masked repetition priming effect. Furthermore, the magnitude of the masked repetition priming effect was greater when the upper part of the primes was preserved than when the lower portion was preserved –this was the case not only when the mutilated words were presented in lowercase but also when the mutilated words were presented in uppercase. Taken together, these findings suggest that the front-end of computational models of visual-word recognition should be modified to provide a more realistic account at the level of letter features.The research reported in this article has been partially supported by Grant PSI2008-04069/PSIC and CONSOLIDER-INGENIO2010 CSD2008-00048 from the Spanish Ministry of Science and Innovation and by Grant PTDC/PSI-PCO/104671/2008 from the Portuguese Foundation for Science and Technology

    TRY plant trait database – enhanced coverage and open access

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    Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Directional Gateway to Metal Oxidation: 3D Chemical Mapping Unfolds Oxygen Diffusional Pathways in Rhodium Nanoparticles

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    The interaction of oxygen with a reactive metal is ubiquitous, yet the precise atomic-level mechanisms and pathways leading to the formation of a surface oxide are not well-understood. We report oxygen atom distributions inside Rh single nanoparticles using atom probe microscopy (APM) and demonstrate that mainly facets of the «022¯Â» crystallographic directions act as oxygen-permeable gateways. The highly anisotropic spatial distribution of incorporated oxygen atoms is in agreement with video-field emission analyses according to which {113} facets of the «022¯Â» zones act as portals for subsurface diffusion. In addition to providing a more fundamental understanding of the precursor states to metal corrosion, in particular for the case of nanosized metal particles, our studies are also relevant for heterogeneous catalysis where catalytic activity and selectivity conform to reaction-induced structural changes of metal nanoparticles.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

    Surface/Subsurface Interactions During Rh Oxidation Revealed by Atom Probe Tomography and Microscopy

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    Metal catalysts may undergo a series of surface and subsurface structural and chemical transformations during a chemical reaction, which inevitably change the surface properties. Understanding such dynamics from a fundamental science standpoint is important to build rational links between chemical/structural surface properties and the desired catalytic performance. The research presented here addresses, the dynamics of early oxide formation on rhodium (Rh) single nanoparticle during O2 exposures revealing the important role that the subsurface plays. O2 dissociative adsorption, as well as its reaction with H2 mainly imply the Rh{012} regions and is directly observable on Rh nanoparticles with the use of Field Ion and Emission Microscopies (FIM/FEM). Adsorbed oxygen atoms (O(ads)) resulting of the O2 dissociative adsorption can migrate to the bulk through the surface. The combination of our observations by FEM and our observations using Atom Probe Tomography (APT) reveals an inter-facet cooperation between Rh{012} and Rh{113} during this process.info:eu-repo/semantics/publishe
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