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A general expression containing all the divergences in Chiral Perturbation Theory at one loop for anomalous processes has been calculated. The nonrenormalization of some amplitudes (Adler-Bardeen theorem) is observed. The different types of corrections are identified. The contributions from vector meson exchange are determined for all anomalous processes. Explicit cancellation of divergences is sh
We present a calculation of the hadronic light-by-light contributions to the muon g-2 in the 1/Nc expansion. We have used an extended Nambu-Jona-Lansinio model and introduced an explicit cutoff for the high energy region. We then have critically studied the relative size of the high energy contributions. Although we find them large, we can give an estimate of the light-by-light contribution to aμ
Using two different methods inspired by duality transformations we present the equivalence between effective Lagrangians for massive vector mesons using a vector field and an antisymmetric tensor field. This completes the list of explicit field transformations between the various effective Lagrangian methods to describe massive vector and axial vector mesons. Our method automatically generates the
We use the 1/Nc method to estimate electromagnetic contributions to vector meson masses and mixings. We identify several new sources of ρ - ω mixing coming from short-distance effects. We comment on the extraction of quark masses from the vector meson masses. We also present a simple group theoretical discussion of the electromagnetic mass differences.
We estimate the 0 electromagnetic mass difference within the 1/N expansion approach to hadronic matrix elements. Perturbative QCD and a truncated meson theory describe the high- and low-photon-loop-momentum contributions, respectively. The matching between these complementary pictures for strong interactions is discussed.
According to Swärd (2012, p. 36), poverty has “many faces and its appearance is dependent upon time, place and type of society, ideological ideas and values”. The aim of this article was to study the beliefs about poverty held by Swedish students of social work, nursing and pre-school teaching. The study employed the experimental factorial survey vignette method, involving the use of fictitious de
As a part of the greening of the EU's Common Agricultural Policy in 2013, Ecological Focus Areas (EFA) became mandatory for many European farmers, with the aim to enhance on-farm biodiversity. However, their effects on biodiversity have been disputed. In this interdisciplinary effort, we assessed the effects of current and alternative formulations of EFA regulations in Sweden. By complementing eco
Syftet med artikeln är att introducera och demonstrera ett pedagogiskt verktyg baserat på användningen av fiktiva fall (vinjetter) konstruerade enligt den experimentella faktoriella surveymetodens principer. Dessa vinjetter är – till skillnad från traditionella ”case” eller ”fallbeskrivningar” – helt igenom kvantitativa, i betydelsen att de kan analyseras i termer av ett antal variabler (dimension
Aims: In this research we assessed the prevalence of prediabetes and type 2 diabetes and its association with social determinants such as indigenous origin and residence area in population from Comitan, Chiapas, Mexico. Methods: The Comitan Study is a population-based study carried out from 2010 to 2012 that included 1844 participants aged ≥ 20 years, 880 indigenous and 964 nonindigenous participa
Purpose: Perceived support from co-workers and managers is important for many organizational outcomes. However, the benefit of competence support from colleagues and school management on personal teacher efficacy has not been investigated. The purpose of this paper is twofold: first, to investigate the impact of competence support from colleagues and the school management on growth in teacher effi
