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    Directing Surface Functions by Inducing Ordered and Irregular Morphologies at Single and Two-Tiered Length Scales

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    Surface topography outlines material's interaction with its immediate environment. Herein, a series of cost-effective and scalable treatments are used to obtain single-scale and two-tiered surfaces with ordered/disordered arrangements of micro and nano features. The applied treatments induced a wide variety of surface features regarding length scale and arrangement. The individual and synergistic contributions of roughness length scale, regularity, and hierarchy are analyzed on surface functionalities. The performance of further functionalized and lubricant-infused surfaces is evaluated regarding their interaction with wetting media, as well as tribological and electrochemical resistance. The hierarchical surfaces show improved wear and corrosion resistance. The prominence of the surface features’ length scale and orderedness varies based on the loading conditions and test environments. Wettability is mainly directed by micro-scale features. Tribology is largely led by the ability of the surfaces in forming a stable low-surface-energy liquid interface. Electrochemical activity is primarily influenced by the synergic barrier effect of the nano-features and the infused lubricant regardless of their arrangement. The results indicate that combining the distinctive and complementary role of micro and nano features can offer the possibility of obtaining versatile multifunctional surfaces with tunable performances based on the expected in-service conditions

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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