We propose an all-loop expression for scattering amplitudes in planar N=4 super Yang-Mills theory in multi-Regge kinematics valid for all multiplicities, all helicity configurations, and arbitrary logarithmic accuracy. Our expression is arrived at from comparing explicit perturbative results with general expectations from the integrable structure of a closely related collinear limit. A crucial ingredient of the analysis is an all-order extension for the central emission vertex that we recently computed at next-to-leading logarithmic accuracy.
View Article and Find Full Text PDFWe present the fully integrated form of the two-loop four-gluon amplitude in N=2 supersymmetric quantum chromodynamics with gauge group SU(N_{c}) and with N_{f} massless supersymmetric quarks (hypermultiplets) in the fundamental representation. Our result maintains full dependence on N_{c} and N_{f}, and relies on the existence of a compact integrand representation that exhibits the duality between color and kinematics. Specializing to the N=2 superconformal theory, where N_{f}=2N_{c}, we obtain remarkably simple amplitudes that have an analytic structure close to that of N=4 super-Yang-Mills theory, except that now certain lower-weight terms appear.
View Article and Find Full Text PDFThe primary aim of this paper is to introduce Quantitative 3-dimensional Computed Tomography (Q3DCT) for odontoid fractures to assess if fracture characteristics differ between the Anderson and d'Alonso subclasses. Secondarily, we assessed if high energy injury and older age influenced fracture morphology. This retrospective imaging study includes 66 patients who visited one of two level I trauma centers for an odontoid fracture.
View Article and Find Full Text PDFJ Int Relat Dev (Ljubl)
December 2016
This article seeks to bridge the gap between the literature on international organisations (IO) and the field of crisis management (CM) by focusing on two themes: how crisis conditions lead organisations to centralise decision-making and how this subsequently affects an international organisation's autonomy. We do this based on two dimensions inspired by the CM literature, that is, the degree of the perceived time pressure and the precrisis legal institutional framework. The plausibility of the analytical framework is assessed on the basis of three cases: the WHO's dealing with the SARS crisis; the European Commission's dealing with the Mad Cow Disease crisis; and the UN's handling of the humanitarian crisis in the Great Lakes region.
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