1,721,065 research outputs found
Perturbative RGE systematics in precision observables
Full text linkQCD calculations for collider physics make use of perturbative solutions of renormalization group equations. Ambiguities related to these solutions can contribute significantly to systematic uncertainties of theoretical predictions for physical observables. We propose a general method to estimate these systematic effects using techniques inspired by soft-gluon and transverse-momentum resummation approaches. We first discuss the cases of the evolution of strong coupling αs, collinear parton-distribution functions, and transverse-momentum-dependent distributions. We then study the implications for precision observables in hadron-collider processes, such as the deep-inelastic scattering structure functions and the transverse-momentum distribution of the lepton pair in Drell-Yan production
Structure functions and perturbative hysteresis
Full text linkWe discuss hysteresis effects in the perturbative solution of
renormalization group equations for the strong coupling and parton
distribution functions, and study their impact on precision determinations of proton's deep-inelastic structure functions F2 and FL
Impact of gender on the relation between myocardial viability and contractile recovery of post-ischemic left ventricular dysfunction: results of the AMICI multicenter study
No full textChanges on lysosomal compartment during PMA-induced differentiation of THP-1 monocytic cells: Influence of type I and type IV collagens
No full text""hesion during phorbol-12-myristate-13-acetate (PMA)- induced differentiation of THP-1 monocytic cell line was studied. In particular, by morphocytochemical and cytometric approaches, the influence of type I and type IV collagens in an experimental model rep- resentative of three phases (initial, intermediate and terminal) of monocyte-macrophage transition was analyzed. The cells in these three phases of differen- tiation were obtained by using 6, 30 e 60 nM PMA. In this experimental model, referring to adhesion to glass as control, by using the azo-dye coupling me- thod, we have considered the analysis of Acid Phos- phatase (AcP) activity as a marker of differentiated status expression, in relation to the acquisition of macrophagic phenotype. Endosomal\\\/lysosomal sys- tem was further characterized by taking in account the uptake of fluorescent probe LysoTracker Red. Fluorochromization in the various experimental con- ditions was analyzed morphologically (fluorescence microscopy) and quantitatively (static cytometry). Data related to lysosome compartment were integra- ted, from a cytokinetic point of view, by flow cy- tometry measurements of DNA\\\/protein content. Our results have indicated that type I and type IV colla- gens were able to influence, with respect to glass ad- hesion, various differentiation phases. Type I collagen showed the higher effects in the condition of high dif-ferentiation (60 nM PMA), causing an increase in AcP activity and lysosomal system. Type IV collagen, besides determining effects on lysosomal compart- ment of intermediate and terminally differentiated cells, influenced mainly proliferative activity of cells with initial differentiation level (6 nM PMA)."
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Resummation Scales and the Assessment of Theoretical Uncertainties in Parton Distribution Functions
Full text linkWe discuss perturbative solutions of renormalization group equations, and
propose the use of resummation scale techniques in assessing theoretical
uncertainties on the extraction of parton distribution functions from data.Comment: 4 pages, 2 figures. Contribution to Proceedings of 29th Workshop on
Deep-Inelastic Scattering and Related Subjects (May 2022
Variations on the Author
Full text link“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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
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