103,143 research outputs found
Indexed induction and coinduction, fibrationally.
No full textThis paper extends the fibrational approach to induction and coinduction pioneered by Hermida and Jacobs, and developed by the current authors, in two key directions. First, we present a sound coinduction rule for any data type arising as the final coalgebra of a functor, thus relaxing Hermida and Jacobs’ restriction to polynomial data types. For this we introduce the notion of a quotient category with equality (QCE), which both abstracts the standard notion of a fibration of relations constructed from a given fibration, and plays a role in the theory of coinduction dual to that of a comprehension category with unit (CCU) in the theory of induction. Second, we show that indexed inductive and coinductive types also admit sound induction and coinduction rules. Indexed data types often arise as initial algebras and final coalgebras of functors on slice categories, so our key technical results give sufficent conditions under which we can construct, from a CCU (QCE) U : E -> B, a fibration with base B/I that models indexing by I and is also a CCU (QCE)
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
No full textDieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Cysteine mediated multimerization of a recombinant dengue E fragment fused to the P64k protein following immobilized metal ion affinity chromatography
No full textA fragment of the Envelope protein of Dengue 2 virus encoding the amino acid (aa) 286-426 was fused to the P64k protein from Neisseria meningitidis. The hybrid gene (PD5) was expressed in Escherichia coli. The influence of using immobilized metal ion affinity chromatography (IMAC) in the purification process of PD5 was examined. After the elution, PD5 protein formed aggregates of high molecular weight depending on disulfide-bonds. The study of different conditions affecting the redox potential in the system revealed the influence of the copper ions on the multimerization of the protein, whereas metals with minor redox potential-for instance, zinc or nickel ions - did not cause this effect. It was also demonstrated that cysteines involved in this process belonged to the P64k protein. Finally, a PD5 purification process was established reaching a 85% of purity using the Zn2+ as metal ion in the IMAC. This is a very useful finding due to the wide use of P64k as a carrier protein and the advantages of the IMAC as a chromatographic process. © 2003 Elsevier Inc. All rights reserved
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3346: Samuel G. Freedman, author, 2013
No full textPhotograph of author Samuel G. Freedman, at NT Daily Slash meeting in the Mayborn School of Journalism at UNT
Fibrational induction rules for initial algebras
No full textThis paper provides an induction rule that can be used to prove properties of data structures whose types are inductive, i.e., are carriers of initial algebras of functors. Our results are semantic in nature and are inspired by Hermida and Jacobs’ elegant algebraic formulation of induction for polynomial data types. Our contribution is to derive, under slightly different assumptions, an induction rule that is generic over all inductive types, polynomial or not. Our induction rule is generic over the kinds of properties to be proved as well: like Hermida and Jacobs, we work in a general fibrational setting and so can accommodate very general notions of properties on inductive types rather than just those of particular syntactic forms. We establish the correctness of our generic induction rule by reducing induction to iteration. We show how our rule can be instantiated to give induction rules for the data types of rose trees, finite hereditary sets, and hyperfunctions. The former lies outside the scope of Hermida and Jacobs’ work because it is not polynomial; as far as we are aware, no induction rules have been known to exist for the latter two in a general fibrational framework. Our instantiation for hyperfunctions underscores the value of working in the general fibrational setting since this data type cannot be interpreted as a set
Stress relaxation in bending of AISI 316 at 773 K
No full textIn this article, stress relaxation in bending of AISI 316 stainless steel at 773 K during 490 hours is characterized. Samples were cut either parallel or transverse to the rolling direction and treated at different temperatures prior to the bending tests. The mechanical behavior shown by the longitudinal samples is quite different from that of the transverse samples and so we conclude there must be differences at the level of their microstructures. However, the presence of sigma phase precipitates in both cases is the consequence of a stress-assisted process. Besides, intragranular carbide density in either sample proved to be a function of the relaxation time.Fil: Povolo, Francisco. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mansilla, G. A.. Universidad Tecnológica Nacional. Facultad Regional San Nicolás; ArgentinaFil: Hermida, Elida Beatriz. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Results in clinical practice in the treatment of severe eosinophilic asthma with mepolizumab: a real-life study
No full textEnríquez-Rodríguez, A.I., Hermida Valverde, T., Romero Álvarez, P., López-González, F.J., Gullón Blanco, J.A., Expósito Villegas, A.R., Escobar Fernández, M.J., Beristáin Urquiza, A.M., Alonso Fernández, M.Á., Gutiérrez Rodríguez, M., Castaño De las Pozas, G., Jiménez Pérez, J., Fernández Mellado, R., García Clemente, M.M., Casan Clara, P
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