1,721,650 research outputs found
Branching ratio of the "second class" tau-->eta' pi nu_tau decay
No full textThe high mass neutral quantum states envisaged by theories of
physics beyond the standard model can at the hadron colliders
reveal themselves through their decay into a pair of photons. Once such a peak in the diphoton invariant mass distribution is
discovered, the determination of its spin through the distinctive
photon angular distributions is needed in order to identify the
associated nonstandard dynamics. We here discuss the
discrimination of the spin-2 Randall-Sundrum graviton excitation
against the hypothesis of a spin-0 exchange giving the same number of events under the peak, by means of the angular analysis applied to resonant diphoton events expected to be observed at the LHC.
The spin-0 hypothesis is modelled by an effective interaction of a
high mass, gauge singlet, scalar particle interacting with the
standard model fields. The basic observable of our analysis is the
symmetrically integrated angular asymmetry A_CE,
calculated for both graviton and scalar s-channel exchanges
to next-to-leading order in QCD
Variante no gene AP1G1 associada a características fenotípicas da síndrome de Usmani-Riazuddin: primeiro relato de caso brasileiro
Full text linkPathogenic variants in the AP1G1 gene (MIM* 603533) have recently been linked to Usmani-Riazuddin syndrome (USRISR, MIM# 619548; USRISD, MIM# 619467), a very rare genetic condition characterized by multisystem involvement. This syndrome manifests with symptoms such as intellectual disability, speech and developmental delays, and behavioral anomalies. The AP1G1 gene plays a crucial role in producing the 822-amino-acid subunit of gamma-adaptin (γ) within the AP-1 complex (AP1γ). In this report, we present a Brazilian boy who exhibits moderate intellectual impairment, overall developmental delay, autistic features, aggressive behavior, and an absence of speech with a previously reported variant in the AP1G1 gene (c.44G>A; p.Arg15Gln). This case marks the first Brazilian case and the fourth documented instance of Usmani-Riazuddin syndrome associated with an AP1G1 variant. Our findings contribute to the understanding of the phenotypic characteristics of this condition and further assert the association between the AP1G1 gene and Usmani-Riazuddin syndrome.Introdução: Variantes patogênicas no gene AP1G1 (MIM* 603533) foram recentemente associadas à síndrome de Usmani-Riazuddin(USRISR, MIM# 619548; USRISD, MIM# 619467), uma condição genética muito rara caracterizada por envolvimento multissistêmico.Essa síndrome se manifesta com sintomas tais como deficiência intelectual, atrasos na fala e no desenvolvimento e anomaliascomportamentais. O gene AP1G1 desempenha um papel crucial na produção da subunidade de 822 aminoácidos da gama-adaptina(γ) dentro do complexo AP-1 (AP1γ). Objetivo: Neste estudo, relatamos um menino com comprometimento intelectual moderado,atraso geral no desenvolvimento, transtorno do espectro autista, comportamento agressivo e ausência de fala o qual apresentou umavariante previamente identificada no gene AP1G1 (c.44G>A; p.Arg15Gln). Resultado: Este caso marca o primeiro caso brasileiro e oquarto caso documentado de síndrome de Usmani-Riazuddin associada a uma variante no gene AP1G1. Conclusão: Nossos achadoscontribuem para a compreensão das características fenotípicas dessa condição e reforçam a associação entre o gene AP1G1 e asíndrome de Usmani-Riazuddin
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
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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